Pain Sketches to Predict Pain following Primary Targeted Muscle Reinnervation in Amputees

BACKGROUND

Numeric scales are validated methods to report pain outcomes after targeted muscle reinnervation (TMR) but do not include the assessment of qualitative pain components. This study evaluates the application of pain sketches within a cohort of patients undergoing primary TMR and describes differences in pain progression according to early postoperative sketches.

METHODS

This study included 30 patients with major limb amputation and primary TMR. Patients' drawings were categorized into four categories of pain distribution [focal pain (FP), radiating pain (RP), diffuse pain (DP), or no pain (NP)] and interrater reliability was calculated. Second, pain outcomes were analyzed for each category. Pain scores were the primary outcome, and Patient-Reported Outcomes Measurement Information System (PROMIS) instruments were the secondary outcome.

RESULTS

The interrater reliability for the sketch categories was good (overall kappa coefficient of 0.8). The NP category reported a mean decrease in pain of 4.8 points, followed by the DP (2.5 points) and FP categories (2.0 points). The RP category reported a mean increase in pain of 0.5 points. For PROMIS Pain Interference and Pain Intensity, the DP category reported a mean decrease of 7.2 and 6.5 points, respectively, followed by the FP category (5.3 and 3.6 points). The RP category reported a mean increase of 2.0 points in PROMIS Pain Interference and a mean decrease of 1.4 points in PROMIS Pain Intensity. Secondary outcomes for the NP category were not reported.

CONCLUSION

Pain sketches demonstrated reliability in pain morphology assessment and might be an adjunctive tool for pain interpretation in this setting.

Improved long-term functional outcomes and mortality of patients with vascular-related amputations utilizing the lower extremity amputation pathway

BACKGROUND

Enhanced recovery after surgery pathways lead to improve perioperative outcomes for patients with vascular-related amputations; however, long-term data and functional outcomes are lacking. This study evaluated patients treated by the lower extremity amputation pathway (LEAP) and identified predictors of ambulation.

METHODS

A retrospective review of LEAP patients who underwent major amputation from 2016 to 2022 for Wound, Ischemia, and foot Infection stage V disease was performed. LEAP patients were matched 1:1 with retrospective controls (NOLEAP) by hospital, need for guillotine amputation, and final amputation type (above knee vs below knee). The primary end point was the Medicare Functional Classification Level (K level) (functional classification of patients with amputations) at the last follow-up.

RESULTS

We included 126 patients with vascular-related amputations (63 LEAP and 63 NOLEAP). Seventy-one percent of the patients were male and 49% were Hispanic with a mean state Area Deprivation Index of 9/10. There were no differences in baseline demographics or comorbidities. All patients had a K level of >0 (ambulatory) before amputation and an average Modified Frailty Index of 4. The median follow-up was 270 days (interquartile range, 84-1234 days) in the NOLEAP group and 369 days (interquartile range, 145-481 days) in the LEAP group. Compared with NOLEAP patients, LEAP patients were more likely to receive a prosthesis (86% vs 44%;P > .001). LEAP patients were more likely to have a K level of >0 (60% vs 25%; P = .003). On multivariable logistic regression, participation in LEAP increased the odds of a K level of >0 at follow-up by 5.8-fold (odds ratio, 5.8; 95% confidence interval, 2.5-13.6). Patients with a K level of >0 had significantly higher survival at 4 years (93% vs 59%; P = .001). In a Cox proportional hazards model, adjusted for demographics, comorbidities and amputation level, a K level of >0 at follow-up was associated with an 88% decrease in the risk of mortality compared with a K level of 0.

CONCLUSIONS

LEAP leads to improved ambulation with a prosthesis in a socioeconomically disadvantaged and frail patient population. Patients with a K level of >0 (ambulatory) have significantly improved mortality.

Can Early Post-Operative Scoring of Non-Traumatic Amputees Decrease Rates of Revision Surgery?

Background and Objectives: Medical registries evolved from a basic epidemiological data set to further applications allowing deriving decision making. Revision rates after non-traumatic amputation are high and dramatically impact the following rehabilitation of the amputee. Risk scores for revision surgery after non-traumatic lower limb amputation are still missing. The main objective was to create an amputation registry allowing us to determine risk factors for revision surgery after non-traumatic lower-limb amputation and to develop a score for an early detection and decision-making tool for the therapeutic course of patients at risk for non-traumatic lower limb amputation and/or revision surgery. Materials and Methods: Retrospective data analysis was of patients with major amputations lower limbs in a four-year interval at a University Hospital of maximum care. Medical records of 164 patients analysed demographics, comorbidities, and amputation-related factors. Descriptive statistics analysed demographics, prevalence of amputation level and comorbidities of non-traumatic lower limb amputees with and without revision surgery. Correlation analysis identified parameters determining revision surgery. Results: In 4 years, 199 major amputations were performed; 88% were amputated for non-traumatic reasons. A total of 27% of the non-traumatic cohort needed revision surgery. Peripheral vascular disease (PVD) (72%), atherosclerosis (69%), diabetes (42%), arterial hypertension (38%), overweight (BMI > 25), initial gangrene (47%), sepsis (19%), age > 68.2 years and nicotine abuse (17%) were set as relevant within this study and given a non-traumatic amputation score. Correlation analysis revealed delayed wound healing (confidence interval: 64.1% (47.18%; 78.8%)), a hospital length of stay before amputation of longer than 32 days (confidence interval: 32.3 (23.2; 41.3)), and a BKA amputation level (confidence interval: 74.4% (58%; 87%)) as risk factors for revision surgery after non-traumatic amputation. A combined score including all parameters was drafted to identify non-traumatic amputees at risk for revision surgery. Conclusions: Our results describe novel scoring systems for risk assessment for non-traumatic amputations and for revision surgery at non-traumatic amputations. It may be used after further prospective evaluation as an early-warning system for amputated limbs at risk of revision.

Performance of non-invasive bedside vascular testing in the prediction of wound healing or amputation among people with foot ulcers in diabetes: A systematic review

INTRODUCTION

The presence of peripheral artery disease (PAD) confers a significantly increased risk of failure to heal and major lower limb amputation for people with diabetes-related foot ulcer (DFU). Determining performance of non-invasive bedside tests for predicting likely DFU outcomes is therefore key to effective risk stratification of patients with DFU and PAD to guide management decisions. The aim of this systematic review was to determine the performance of non-invasive bedside tests for PAD to predict DFU healing, healing post-minor amputation, or need for minor or major amputation in people with diabetes and DFU or gangrene.

METHODS

A database search of Medline and Embase was conducted from 1980 to 30 November 2022. Prospective studies that evaluated non-invasive bedside tests in patients with diabetes, with and without PAD and foot ulceration or gangrene to predict the outcomes of DFU healing, minor amputation, and major amputation with or without revascularisation, were eligible. Included studies were required to have a minimum 6-month follow-up period and report adequate data to calculate the positive likelihood ratio (PLR) and negative likelihood ratio for the outcomes of DFU healing, and minor and major amputation. Methodological quality was assessed using the Quality in Prognosis Studies tool.

RESULTS

From 14,820 abstracts screened 28 prognostic studies met the inclusion criteria. The prognostic tests evaluated by the studies included: ankle-brachial index (ABI) in 9 studies; ankle pressures in 10 studies, toe-brachial index in 4 studies, toe pressure in 9 studies, transcutaneous oxygen pressure (TcPO2 ) in 7 studies, skin perfusion pressure in 5 studies, continuous wave Doppler (pedal waveforms) in 2 studies, pedal pulses in 3 studies, and ankle peak systolic velocity in 1 study. Study quality was variable. Common reasons for studies having a moderate or high risk of bias were poorly described study participation, attrition rates, and inadequate adjustment for confounders. In people with DFU, toe pressure ≥30 mmHg, TcPO2 ≥25 mmHg, and skin perfusion pressure of ≥40 mmHg were associated with a moderate to large increase in pretest probability of healing in people with DFU. Toe pressure ≥30 mmHg was associated with a moderate increase in healing post-minor amputation. An ABI using a threshold of ≥0.9 did not increase the pretest probability of DFU healing, whereas an ABI <0.5 was associated with a moderate increase in pretest probability of non-healing. Few studies investigated amputation outcomes. An ABI <0.4 demonstrated the largest increase in pretest probability of a major amputation (PLR ≥10).

CONCLUSIONS

Prognostic capacity of bedside testing for DFU healing and amputation is variable. A toe pressure ≥30 mmHg, TcPO2 ≥25 mmHg, and skin perfusion pressure of ≥40 mmHg are associated with a moderate to large increase in pretest probability of healing in people with DFU. There are little data available evaluating the prognostic capacity of bedside testing for healing after minor amputation or for major amputation in people with DFU. Current evidence suggests that an ABI <0.4 may be associated with a large increase in risk of major amputation. The findings of this systematic review need to be interpreted in the context of limitations of available evidence, including varying rates of revascularisation, lack of post-revascularisation bedside testing, and heterogenous subpopulations.

Impact of Care Fragmentation after Major Lower Extremity Amputation

BACKGROUND

Care fragmentation (CF) is a known risk factor for unplanned readmission, morbidity, and mortality after surgery. The goal of this study was to evaluate the impact of CF on outcomes of major lower extremity amputation for peripheral vascular disease.

METHODS

Health-care Cost and Utilization Project Database for NY (2016) and MD/FL (2016-2017) were queried using International Classification of Diseases 10thedition to identify patients who underwent above the knee-, through the knee-, and below the knee-amputation for peripheral vascular disease. Patients with CF were identified as those with admissions to ≥2 hospitals during the study period. We compared the postamputation outcomes of mortality, readmission rate, length of stay (LOS) and hospital charges.

RESULTS

We identified a total of 13,749 encounters of 2,742 patients who underwent major lower extremity amputations. There were 1,624 (59.2%) patients with CF. Patients with CF were younger (68.4 years old vs. 69.7 years old, P = 0.005), with higher Charlson Comorbidity Indices (4.4 vs. 4.1, P < 0.001), and required more hospital resources on index admission ($113,699 vs. $91,854, P < 0.001). These patients were prevalent for higher 30-, and 90-day readmission rates (34.7% vs. 24.5%, P < 0.001 and 54.7% vs. 42.0%, P < 0.001, respectively). On their first postamputation readmission, LOS (16.3 days vs. 14.7 days, P = 0.004) and hospital charge ($48,964 vs. $44,388, P = 0.002) were significantly higher. Multivariate regression analysis demonstrated that the CF was an independent predictor for 30-day (hazard ratio (HR) 1.65, 95% confidence interval (CI) 1.39-1.96, P < 0.001) and 90-day (HR 1.66, 95% CI 1.42-1.95, P < 0.001) readmission after the major lower extremity amputation, but not for mortality (HR 0.83, 95% CI 0.56-1.23, P = 0.36).

CONCLUSIONS

CF after major lower extremity amputation is associated with higher readmission rate, LOS, and hospital charge. Collaboration of care providers to maintain continuity of care for peripheral vascular disease patients may enhance quality of care and reduce health care cost.

Graded motor imagery and its phases for individuals with phantom limb pain following amputation: A scoping review

OBJECTIVE

Three-phase graded motor imagery (limb laterality, explicit motor imagery, and mirror therapy) has been successful in chronic pain populations. However, when applied to phantom limb pain, an amputation-related pain, investigations often use mirror therapy alone. We aimed to explore evidence for graded motor imagery and its phases to treat phantom limb pain.

DATA SOURCES

A scoping review was conducted following the JBI Manual of Synthesis and Preferred Reporting Items for Systematic Review and Meta-Analyses extension for Scoping Reviews. Thirteen databases, registers, and websites were searched.

REVIEW METHODS

Published works on any date prior to the search (August 2023) were included that involved one or more graded motor imagery phases for participants ages 18+ with amputation and phantom limb pain. Extracted data included study characteristics, participant demographics, treatment characteristics, and outcomes.

RESULTS

Sixty-one works were included representing 19 countries. Most were uncontrolled studies (31%). Many participants were male (75%) and had unilateral amputations (90%) of varying levels, causes, and duration. Most works examined one treatment phase (92%), most often mirror therapy (84%). Few works (3%) reported three-phase intervention. Dosing was inconsistent across studies. The most measured outcome was pain intensity (95%).

CONCLUSION

Despite the success of three-phase graded motor imagery in other pain populations, phantom limb pain research focuses on mirror therapy, largely ignoring other phases. Participant demographics varied, making comparisons difficult. Future work should evaluate graded motor imagery effects and indicators of patient success. The represented countries indicate that graded motor imagery phases are implemented internationally, so future work could have a widespread impact.

Investigation of the effect of acute to chronic glycemic ratio on major amputation development after surgical thromboembolectomy in patients with acute lower extremity ischemia

BACKGROUND

Acute limb ischemia (ALI) is an emergency vascular pathology in which perfusion is disrupted in the lower extremity and threatens extremity viability. The admission blood glucose (ABG)/estimated average glucose (eAG) value has recently been shown as a prognostic marker in acute cardiovascular events. In this study, we aimed to investigate the predictive role of an ABG/eAG value in predicting development of early postoperative major amputation after emergency thromboembolectomy operations in patients presenting with ALI.

METHOD

Patients who admitted to our hospital with ALI between November 01, 2016 and September 01, 2021 and underwent surgical thromboembolectomy were retrospectively included in the study. Patients who did not undergo postoperative limb amputation were recorded as Group 1, and patients who underwent major amputation in the early postoperative period (in-hospital), were recorded as Group 2.

RESULTS

The median age of the 226 patients included in Group 1 and 72 patients in Group 2 were 58 (34-86) years and 69 (33-91) years, respectively (p<0.001). In univariate analysis, in-hospital amputation was found to significantly correlate with age>70 years (odds ratio [OR]: 1.914, 95% confidence interval [CI]: 1.351-2.319, p<0.001), PAD (OR: 1.698, 95% CI: 1.270-1.992, p = 0.002 re-embolectomy (OR: 2.184, 95% CI: 1.663-3.085, p < 0.001), admission Rutherford class (OR: 0.762, 95% CI: 0.591-0.859, p = 0.032), admission time>6 h (OR: 1.770, 95% CI: 1.480-1.152, p = 0.009), ABG (OR: 1.275, 95% CI: 1.050-1.790, p < 0.001), and ABG/eAG (OR: 1.669, 95% CI: 1.315-2.239, p < 0.001).

CONCLUSION

According to our study, we can predict patient groups with a high risk of major amputation with the ABG/eAG value calculated from the blood values of the patients at the time of admission.

Bone-anchored prostheses for lower limb amputation in a French cohort with 1-15 years of follow-up: implant survival rates, mechanical complications, and reported outcomes

PURPOSE

To evaluate the implant survival rate, mechanical complications, and reported patient outcomes of bone-anchored prostheses for patients with lower limb amputation in France after 1-15 years of follow-up.

METHODS

This retrospective cohort study included patients who underwent surgery at a single center in France between 2007 and 2021. The primary outcomes were the implant survival rate and functional scores assessed by the Questionnaire for Transfemoral Amputees (Q-TFA). Secondary outcomes were adverse events that occurred during follow-up.

RESULTS

The cohort consisted of 20 bone-anchored prostheses in 17 patients. The main level of amputation was transfemoral (82%, n = 14). The main reason for amputation was trauma (n = 15). The mean age at amputation was 32 (range 15-54) years, and the mean age at the first stage of osseointegration was 41 (range 21-58) years. The Kaplan-Meier survival curve showed respective survival rates of 90%, 70%, and 60% at 2, 10, and 15 years. All Q-TFA scores were significantly improved at last the follow-up. Eleven patients (65%) experienced mechanical complications. In total, 37 infectious events occurred in 13 patients (76%), mainly comprising stage 1 infections (68%, n = 25). Only two cases of septic loosening occurred (12%), leading to implant removal.

CONCLUSION

This is the first French cohort of bone-anchored prostheses and among the series with the longest follow-up periods. The findings indicate that bone-anchored prostheses are safe and reliable for amputee patients who have difficulties with classic prostheses.

Predisposing Factors for 30-Day Complications Following Leg Amputation

BACKGROUND

Although amputation rates, morbidity, and mortality have been established for select populations, the impact of general demographic factors on postoperative surgical complications remains little studied.

METHODS

The American College of Surgeons' National Surgical Quality Improvement Program database was searched for leg amputations from 2012 to 2017 using CPT codes 27881, 27882, 27884, and 27886, identifying 4162 patients. A total of 29 demographic variables with 4 complications (surgical infection, additional service, and deep-vein thrombosis [DVT], and sepsis) were analyzed.

RESULTS

Preoperative open, contaminated, or dirty/infected wounds; longer intraoperative times; development of sepsis prior to surgery; and admission of patients from home or another hospital influenced postoperative infection rates. Preoperative open, infected, or dirty/infected wounds; height; weight; total length of hospital stay; and ethnicity affected postoperative additional service incidence. Preoperative congestive heart failure, large decreases in body weight, and total length of hospital stay influenced postoperative DVT rates. Preoperative functional heath status, total length of hospital stay, amputations conducted as emergency cases, preoperative acute renal failure, open or infected wounds, sepsis, and contaminated or dirty/infected wounds affected postoperative sepsis rates.

BACKGROUND

Conclusion. Understanding these risk factors may allow providers to anticipate and address higher rates of complications in certain patient populations.

LEVEL OF EVIDENCE

Level III: Prognostic.

Targeted muscle reinnervation: A narrative review of a novel tool for the management of neuropathic pathology in major lower extremity amputations

OBJECTIVE

The purpose of this narrative review is to provide the vascular surgery community with updated recommendations and information regarding the use of Targeted Muscle Reinnervation (TMR) for both the prevention and treatment of chronic pain and phantom limb pain occurring in patients after undergoing lower extremity amputation for peripheral artery disease.

METHODS

Current available literature discussing TMR is reviewed and included in the article in order to provide a succinct overview on the indications, clinical applications, and surgical technique for TMR. Additionally, early studies showing favorable long-term results after TMR are discussed. Patient consent for publication was obtained for this investigation.

RESULTS

TMR has been demonstrated to be an effective means of both treating and preventing neuroma-related symptoms including chronic pain and phantom limb pain. It has been proven to be technically feasible, and can help patients to have improved utilization of prostheses for ambulation, which can conceivably lead to a reduction in mortality.

CONCLUSIONS

TMR is an important tool to consider for any patient undergoing lower extremity amputation for a vascular-related indication. A vascular-plastic surgeon dual team approach is an effective means to prevent and reduce neuromas and associated chronic pain in this patient population.

Phantom Limb Pain and Painful Neuroma After Dysvascular Lower-Extremity Amputation: A Systematic Review and Meta-Analysis

BACKGROUND

Phantom limb pain (PLP) and symptomatic neuroma can be debilitating and significantly impact the quality of life of amputees. However, the prevalence of PLP and symptomatic neuromas in patients following dysvascular lower limb amputation (LLA) has not been reliably established. This systematic review and meta-analysis evaluates the prevalence and incidence of phantom limb pain and symptomatic neuroma after dysvascular LLA.

METHODS

Four databases (Embase, MEDLINE, Cochrane Central, and Web of Science) were searched on October 5th, 2022. Prospective or retrospective observational cohort studies or cross-sectional studies reporting either the prevalence or incidence of phantom limb pain and/or symptomatic neuroma following dysvascular LLA were identified. Two reviewers independently conducted the screening, data extraction, and the risk of bias assessment according to the PRISMA guidelines. To estimate the prevalence of phantom limb pain, a meta-analysis using a random effects model was performed.

RESULTS

Twelve articles were included in the quantitative analysis, including 1924 amputees. A meta-analysis demonstrated that 69% of patients after dysvascular LLA experience phantom limb pain (95% CI 53-86%). The reported pain intensity on a scale from 0-10 in LLA patients ranged between 2.3 ± 1.4 and 5.5 ± .7. A single study reported an incidence of symptomatic neuroma following dysvascular LLA of 5%.

CONCLUSIONS

This meta-analysis demonstrates the high prevalence of phantom limb pain after dysvascular LLA. Given the often prolonged and disabling nature of neuropathic pain and the difficulties managing it, more consideration needs to be given to strategies to prevent it at the time of amputation.

[Lower Limb Amputations in Patients with Peripheral Arterial Disease and/or Diabetes in Iceland 2010-2019; revascularisation, comorbidities and risk factors]

INTRODUCTION

No recent studies exist on lower extremity amputations (LLAs) in Iceland. The aim of this study was to investigate LLA incidence in Iceland 2010-2019 and preceding procedures in amputations induced by peripheral arterial disease (PAD) and diabetes mellitus (DM).

MATERIAL AND METHODS

Retrospective study on clinical records of all patients (>18 years) who underwent LLA in Iceland's two main hospitals during 2010-2019. Patients were excluded if LLA was performed for reasons other than DM and/or PAD. Symptoms, medication and circulation assessment were recorded from first hospital visit due to symptoms, and prior to the last LLA, respectively. Previous arterial surgeries and amputations were also recorded.

RESULTS

A total of 167 patients underwent LLA. Thereof, 134 (77 ± 11 years, 93 men and 41 woman) due to DM and/or PAD. The LLA-rate due to those diseases increased from 4.1/100,000 inhabitants in 2010-2013 to 6.7/100,000 in 2016-2019 (p=0,04). Risk factors were mainly hypertension, 84%, and smoking, 69%. Chronic limb-threatening ischemia induced 71% of first hospital visits. Revascularisations were performed (66% endovascular) in 101 patients. Non-diabetic patients were 52% and had statins less frequently prescribed than DM patients (26:45, p<0.001).

CONCLUSION

DM and/or PAD are the leading causes of LLA in Iceland. Amputation rate increased during the period but is low in an international context. Amputation is most often preceded by arterial surgery. DM is present in almost half of cases, similar or less than in most other countries. Opportunities for improved prevention should aim on earlier diagnosis and preventive treatment of non-diabetic individuals with PAD.

Assessment of the risk factors determining the prognosis of major and minor limb amputations in patients with diabetic foot ulcers

BACKGROUND

Diabetes mellitus (DM) is a major global health problem, and its incidence is growing. Depending on this increase, the number of diabetes-related complications will also rise.

OBJECTIVES

This study aimed to determine the risk factors associated with major and minor amputations resulting from diabetes.

MATERIAL AND METHODS

Patients diagnosed with diabetic foot complications (n = 371) and hospitalized between January 2019 and March 2020 were retrospectively evaluated using information obtained from the database of Diabetic Foot Wound Clinic. Examination of the data identified 165 patients for inclusion in the study, who were stratified into major amputation (group 1, n = 32), minor amputation (group 2, n = 66) and non-amputation (group 3, n = 67) groups.

RESULTS

Of the 32 patients who underwent major amputations, 84% had a below-knee amputation, 13% had an above-knee amputation and 3% had knee disarticulation. At the same time, 73% of 66 patients who underwent minor amputation had a single-finger amputation, 17% had a multiple-finger amputation, 8% had a transmetatarsal amputation, and 2% had Lisfranc amputation. Laboratory results showed high acute phase protein and low albumin (ALB) levels in patients from group 1 (p < 0.05). Although Staphylococcus aureus was found to be the most common infectious agent, Gram-negative pathogens were dominant (p < 0.05). Also, there was a significant cost difference between the groups (p < 0.05). Furthermore, those aged over 65 had a high Wagner score, high Charlson Comorbidity Index (CCI), long diabetic foot ulcer (DFU) duration, and high white blood cell (WBC) count, all of which were risk factors for major amputation (p < 0.05).

CONCLUSIONS

This study demonstrated an increased Wagner staging and incidence of peripheral neuropathy (PN) and peripheral arterial disease (PAD) in major amputation patients. In addition, the rate of distal vessel involvement was high in major amputation patients, with elevated acute phase proteins and low ALB levels crucial in laboratory findings.

Impact of Intensity of Vascular Care Preceding Major Amputation Among Patients With Chronic Limb-Threatening Ischemia

BACKGROUND

Lower-limb amputation rates in patients with chronic limb-threatening ischemia vary across the United States, with marked disparities in amputation rates by gender, race, and income status. We evaluated the association of patient, hospital, and geographic characteristics with the intensity of vascular care received the year before a major lower-limb amputation and how intensity of care associates with outcomes after amputation.

METHODS

Using Medicare claims data (2016-2019), beneficiaries diagnosed with chronic limb-threatening ischemia who underwent a major lower-limb amputation were identified. We examined patient, hospital, and geographic characteristics associated with the intensity of vascular care received the year before amputation. Secondary objectives evaluated all-cause mortality and adverse events following amputation.

RESULTS

Of 33 036 total Medicare beneficiaries undergoing major amputation, 7885 (23.9%) were due to chronic limb-threatening ischemia; of these, 4988 (63.3%) received low-intensity and 2897 (36.7%) received high-intensity vascular care. Mean age, 76.6 years; women, 38.9%; Black adults, 24.5%; and of low income, 35.2%. After multivariable adjustment, those of low income (odds ratio, 0.65 [95% CI, 0.58-0.72]; P<0.001), and to a lesser extent, men (odds ratio, 0.89 [95% CI, 0.81-0.98]; P=0.019), and those who received care at a safety-net hospital (odds ratio, 0.87 [95% CI, 0.78-0.97]; P=0.012) were most likely to receive low intensity of care before amputation. High-intensity care was associated with a lower risk of all-cause mortality 2 years following amputation (hazard ratio, 0.79 [95% CI, 0.74-0.85]; P<0.001).

CONCLUSIONS

Patients who were of low-income status, and to a lesser extent, men, or those cared for at safety-net hospitals were most likely to receive low-intensity vascular care. Low-intensity care was associated with worse long-term event-free survival. These data emphasize the continued disparities that exist in contemporary vascular practice.

Combining Surgical Innovations in Amputation Surgery-Robotic Harvest of the Rectus Abdominis Muscle, Transplantation and Targeted Muscle Reinnervation Improves Myocontrol Capability and Pain in a Transradial Amputee

Adding robotic surgery to bionic reconstruction might open a new dimension. The objective was to evaluate if a robotically harvested rectus abdominis (RA) transplant is a feasible procedure to improve soft-tissue coverage at the residual limb (RL) and serve as a recipient for up to three nerves due to its unique architecture and to allow the generation of additional signals for advanced myoelectric prosthesis control. A transradial amputee with insufficient soft-tissue coverage and painful neuromas underwent the interventions and was observed for 18 months. RA muscle was harvested using robotic-assisted surgery and transplanted to the RL, followed by end-to-end neurroraphy to the recipient nerves of the three muscle segments to reanimate radial, median, and ulnar nerve function. The transplanted muscle healed with partial necrosis of the skin mesh graft. Twelve months later, reliable, and spatially well-defined Hoffmann-Tinel signs were detectable at three segments of the RA muscle flap. No donor-site morbidities were present, and EMG activity could be detected in all three muscle segments. The linear discriminant analysis (LDA) classifier could reliably distinguish three classes within 1% error tolerance using only the three electrodes on the muscle transplant and up to five classes outside the muscle transplant. The combination of these surgical procedure advances with emerging (myo-)control technologies can easily be extended to different amputation levels to reduce RL complications and augment control sites with a limited surface area, thus facilitating the usability of advanced myoelectric prostheses.

Predicting Prosthetic Mobility at Discharge From Rehabilitation Following Major Amputation in Vascular Surgery

OBJECTIVE

This study aimed to construct a decision aid to estimate the likelihood of independence with a prosthesis following rehabilitation for limb loss secondary to advanced ischaemia (acute or chronic limb threatening ischaemia) or diabetic foot disease (DFD). A secondary aim was to determine whether prosthetic independence is a surrogate marker of long term survival.

METHODS

A retrospective cohort study of a prospectively maintained database of unilateral amputations due to ischaemia or DFD entering rehabilitation between 2007 and 2020 was performed. Predictors of independent prosthetic mobility (IPM) were used in construction of the IPM prediction model, which underwent bootstrap internal and criterion validation through correlation with predictors of other measures of function: Timed Up and Go (TUG) and two minute walk test. Kaplan-Meier and Cox regression analyses were performed to address the secondary aim.

RESULTS

Of the 771 patients included, only 49.9% of amputees achieved IPM. Independent negative predictors of IPM were age > 75 years, female sex, higher amputation level, active malignancy, cerebrovascular disease, end stage renal disease, and cognitive impairment. The model yielded high discrimination (C statistic 0.778), and internal validation was demonstrated with bootstrapping (C statistic 0.778), confirming no over optimism. There was a strong correlation between IPM, TUG, and two minute distance and their predictors, confirming strong criterion validity. The IPM group had a median survival of 93.7 (80.7, 105) months, whereas the non-IPM group fared worse with a median survival of 56.6 (48.5, 66.7) months (p < .001).

CONCLUSION

An internally validated decision aid for estimating the likelihood of independence with a prosthesis after major amputation was constructed. A strong association between female sex and poorer prosthetic mobility was observed. Prosthetic function was shown to be a surrogate marker of long term survival. Future research will involve external validation studies to confirm the generalisability of the decision aid in clinical practice.

Investigation of Body Image and Quality of Life of Patients with Lower Limb Amputation: Problems Experienced of Patients

BACKGROUND

Problems related to quality of life and body images of amputee patients are important.

AIMS

This study was performed to assess body image and quality of life with problems experienced of patients with lower limb amputation.

MATERIALS AND METHODS

This study was performed using mixed quantitative dominant study design. The study was carried out in orthopedics and cardiovascular surgery units of a university hospital. Quantitative data were collected from 30 patients via questionnaires including the Short Form-36 Quality of Life (SF-36 QoL) and Amputee Body Image Scale (ABIS) tools. Qualitative data were gathered from 20 patients using an interview form. In this research, quantitative data have been analyzed by using a statistical program and qualitative data have been analyzed by using content analysis.

RESULTS

Age mean of 30 patients with amputation 47.23±16.08. They were 80 % male, 70% have a chronic illness, 63.3% knee disarticulation or transfemoral amputation, and 53.3% use prosthetic. The average SF-36 QoL sub-dimension scores of the patients were: physical 30.11±20.00, social 36.66±27.45, physical roles 18.33±30.03, emotional roles 37.77±22.71, mental health 48.0±22.89, vitality 36.50±20.64, pain 48.13±28.33, and general health 43.96±28.59. The ABIS average score was 60.1±19.62. The most common problem of patients after amputation involves issues related to motion. Three main categories of patients experience with amputation were designated that the reactions after learning that the amputation will be done, problems experienced in the early period after amputation and post-discharge problems.

CONCLUSIONS

Quality of life of patients with amputation was below the intermediate level. Deterioration in body image perception was above average. The most common problem after amputation was issues related mobilization. Training related the amputation process and social support might significantly reduce problems with amputation.

Targeted muscle reinnervation in managing post-amputation related pain: A systematic review and meta-analysis

INTRODUCTION

Limb amputation can cause residual limb pain (RLP) and/or phantom limb pain (PLP). Although targeted muscle reinnervation (TMR) was initially introduced to facilitate the control of prosthetic limbs, it has been noted that these patients experience less pain and improved prosthetic functional outcomes. As a result, the use of TMR in managing neuroma-related RLP is increasing. The aim of this review is to assess the quality and strength of the evidence supporting the effectiveness of TMR in managing amputation-related pain.

METHODS

Five different databases, including MEDLINE (PubMed), Scopus, Web of Science, Cochrane Library, and Embase, were searched from inception to March 2022. The protocol for this systematic review has been registered in the PROSPERO database (CRD42020218242). To be included, studies needed to compare pre- and postoperative pain outcomes or different techniques for adult patients who underwent TMR following amputation. Eligible studies also needed to use patient-reported outcome measures (PROMS) and be clinical trials or observational studies published in English. Excluded studies were case reports, case series, reviews, proof of concept studies, and conference proceedings. A meta-analysis was performed on studies that had similar intervention and control groups to examine treatment effects using a random-effects model. Studies were weighted using the inverse variance method, and a statistically significant p-value was considered to be less than or equal to 0.05.

RESULTS

This review included five studies for qualitative analysis and four studies for quantitative analysis. Reviewed studies enrolled a total of 127 patients. The TMR group was compared with standard treatment at 12 months follow-up. The TMR group showed significantly better PLP as assessed by the numerical rating score RLP, and PLP assessed using Patient-Reported Outcomes Measurement Information System (PROMIS) also showed significantly lower pain intensity in the TMR group.

CONCLUSION

There is limited evidence of good quality favoring TMR in reducing postamputation PLP and RLP pain compared with standard care. Randomized clinical trials are encouraged to compare the efficacy of different surgical techniques.

Indications for and outcomes of major lower limb amputations at a tertiary-referral centre in Australia

OBJECTIVES

Major amputations are classically associated with significant morbidity and mortality. With the increasing prevalence of risk factors for amputation, namely, diabetes and peripheral arterial disease, we sought to identify the major indications for lower limb amputation in an Australian cohort. A secondary aim was to assess the outcomes, namely, mortality, of amputees over the previous decade.

METHODS

This study assessed all patients undergoing major lower limb amputations between 2012 and 2020. Variables analysed included comorbidities, indication for amputation, in-hospital complications and mortality, duration of hospital stay, and out-patient mortality.

RESULTS

317 amputations were performed on 269 patients. 55% of amputations were below knee, 45% above knee, with one through-knee amputation. Indications included ischaemia (55.2%), infection (30.6%), malignancy (6.9%), trauma (4.4%), and chronic pain or instability (2.5%). In-patient mortality rate was 7.6%, with mortality rates of 21.5% at one year, and 70.1% at 10 years. Post-operative complications occurred in 43% of amputations. Rural, regional, and remote (RRR) patients did not suffer disproportionately from major amputations, however, were more likely to require amputations for ischaemia. Patients undergoing amputation for infective causes demonstrated lower mid-term mortality rates compared to those undergoing amputations for ischaemia (56.1 vs 60.4% at 5 years, p = 0.007).

CONCLUSION

Major amputations continue to be associated with significant morbidity and mortality, both in the short and long term. Patients undergoing amputations for ischaemic causes demonstrate poorer outcomes than their infective counterparts, with outcomes being even worse in RRR populations. Prevention of amputations via intense management of comorbidities would benefit both patients and the healthcare system.

Comparison of Outcomes in Below-Knee Amputation Between Vascular, General, and Orthopedic Surgeons

INTRODUCTION

General surgeons (GS), orthopedic surgeons (OS), and vascular surgeons (VS) can perform below-knee amputation (BKA) operations. We compared the outcomes of BKA patients among the three specialties.

METHODS

Adult patients who underwent a BKA were identified from the 2016-2018 National Surgical Quality Improvement Project database. Statistical data for orthopedic and vascular BKA cases were then compared with GS cases using logistic regression analysis. Outcomes included mortality, length of hospital stay, and complications.

RESULTS

There were 9619 BKA cases. VS had the highest volume of BKA with 58.9% of the cases, compared to GS at 22.9% and OS at 18.1%. 4.4% of general surgery patients had severe frailty compared to OS (3.3%) and VS (3.4%, P < 0.001). VS has the lowest rates of emergency cases (11.9% versus 16.1 for GS versus 15.8% versus OS) and the most favorable wound classification (38.3%, versus 48.7% for GS and VS). Peripheral vascular disease was notably highest in VS (34.0% versus. 20.6% for GS and 9.9% for OS, P < 0.001). Compared to GS, VS was more likely to have a prolonged length of stay (odds ratio) (OR)(1.409), 95% CI 1.265-1.570) while OS was less likely (OR 0.650, 95% CI 0.561-0.754). OS had a lower risk of complications (OR 0.781, 95% CI 0.674-0.904). Mortality was not significantly different among the three specialties.

CONCLUSIONS

The National Surgical Quality Improvement Project retrospective analysis of BKA cases suggested that mortality was not statistically different when performed by VS, GS, and OS. There were fewer overall complications when OS performed a BKA, but this is more likely a result of operating upon a generally healthier patient population with lower incidence of preoperative comorbid conditions.

Community-wide feasibility of the Lower Extremity Amputation Protocol amongst vascular amputees

BACKGROUND

The Lower Extremity Amputation Protocol (LEAP) is a multidisciplinary enhanced recovery after surgery pathway for vascular amputees. The objective of this study was to examine feasibility and outcomes of community-wide implementation of LEAP.

METHODS

LEAP was implemented at three safety net hospitals for patients with peripheral artery disease or diabetes requiring major lower extremity amputation. Patients who underwent LEAP (LEAP) were matched 1:1 with retrospective controls (NOLEAP) on hospital location, need for initial guillotine amputation, and final amputation type (above- vs below-knee). Primary endpoint was postoperative hospital length of stay (PO-LOS).

RESULTS

A total of 126 amputees (63 LEAP and 63 NOLEAP) were included with no difference between baseline demographics and co-morbidities between the groups. After matching, both groups had the same prevalence of amputation level (76% below-knee vs 24% above-knee). LEAP patients had shorter duration of postamputation bed rest (P = .003) and were more likely to receive limb protectors (100% vs 40%; P ≤ .001), prosthetic counseling (100% vs 14%; P ≤ .001), perioperative nerve blocks (75% vs 25%; P ≤ .001), and postoperative gabapentin (79% vs 50%; P ≤ .001). Compared with NOLEAP, LEAP patients were more likely to be discharged to an acute rehabilitation facility (70% vs 44%; P = .009) and less likely to be discharged to a skilled nursing facility (14% vs 35%; P = .009). The median PO-LOS for the overall cohort was 4 days. LEAP patients had a shorter median PO-LOS (3 [interquartile range, 2-5] vs 5 [interquartile range, 4-9] days; P < .001). On multivariable logistic regression, LEAP decreased the odds of a PO-LOS of ≥4 days by 77% (odds ratio, 0.23; 95% confidence interval, 0.09-0.63). Overall, LEAP patients were significantly less likely to have phantom limb pain (5% vs 21%; P = .02) and were more likely to receive a prosthesis (81% vs 40%; P ≤ .001). In a multivariable Cox proportional hazards model, LEAP was associated with an 84% reduction in time to receipt of prosthesis (hazard ratio, 0.16; 95% confidence interval, 0.085-0.303; P < .001).

CONCLUSIONS

Community wide implementation of LEAP significantly improved outcomes for vascular amputees demonstrating that utilization of core ERAS principles in vascular patients leads to decreased PO-LOS and improved pain control. LEAP also affords this socioeconomically disadvantaged population a greater opportunity to receive a prosthesis and return to the community as a functional ambulator.

The relationship between lower extremity amputation and body mass index

OBJECTIVES

Non-traumatic lower extremity amputation (LEA) is associated with significant morbidity and mortality. Diabetes mellitus (DM) and peripheral vascular disease (PVD) are associated with increased risk for LEA. As such, DM and PVD account for 54% of all LEA's, performed in the United States annually. As obesity is highly associated with both DM and PVD, our study sought to explore the relationship between LEA and obesity defined by BMI.

METHODS

Using the National Inpatient Sample (NIS) database, a retrospective review of patients who underwent non-traumatic LEA (LEA) between 2008 and 2014 was performed. The International Classification of Diseases 9th edition (ICD-9) codes were utilized to determine the diagnoses, comorbidities, and procedures. Patient BMIs were classified as follows: Non-obese [BMI <30], Obesity class I [BMI 30-34.9], Obesity class II [BMI 35-39.9], and Obesity class III [BMI ≥40]. Predictors for LEA were compared between groups using chi-square test and binary logistic regression to identify possible underlying factors associated with LEA. We also conducted a multivariate analysis to measure the effect of multiple variables on LEA.

RESULTS

We identified 16,259 patients with non-traumatic LEA and a mean age of 59.9 years. Rate of amputation in females was lower than males at 0.35% vs 0.87% respectively (p < 0.001). Of patients that underwent amputation there was a V-shape trend based on BMI, with 30.4% in non-obese patients, 18.2% in obesity class I, 17.3% in obesity class II, and 34.1% in obesity class III. The incidence of diabetes increased with obesity class, while the incidence of PVD decreased. Interestingly, of those with DM there was an inverse relationship between amputation rate and BMI class, with LEA rates in non-obese versus obesity class III patients were 1.63% vs 0.98% respectively (p < 0.001). Similarly, patients who had both diabetes and PVD showed a downward trend in LEA rate as obesity class increased; non-obese patients had a LEA rate of 8.01%, while obesity class III had 4.65% (p < 0.001). Patients in higher income bracket have lower odds of LEA (OR 0.77, p < 0.001) compared to the lowest income patients. Also, patients with comorbidities such as PVD (OR 10.78), diabetes (OR 5.02), renal failure (OR 1.41), and hypertension (OR 1.36) had higher odds to get an LEA (p < 0.001). Individuals with obesity class III are almost at half the odds (OR 0.52) to get an LEA compared to non-obese (p < 0.001).

CONCLUSIONS

Higher BMI and female gender are protective factors against lower extremity amputation. Factors that predisposing to LEA include lower household income and certain comorbidities such as PVD, diabetes, renal failure, and hypertension. These findings warrant further research to identify patients at high risk for LEA and help develop management guidelines for targeted populations.

Opioid utilization after lower extremity amputation for peripheral vascular disease and discharge prescribing recommendations

OBJECTIVES

Opioids are commonly used for pain control after lower extremity amputations (LEA)-below the knee amputations (BKA) and above the knee amputations (AKA). Well-defined benchmarks for prescription requirements after amputation are deficient. This analysis evaluated opioid utilization after amputation to identify high-risk patients and provide recommendations for post-hospitalization opioid prescriptions at discharge.

METHODS

Patients undergoing LEA (2008-2016) with identified peripheral vascular disease were selected from Cerner's Health Facts® database using ICD-9 and 10 diagnosis and procedure codes. Patient demographics, disease severity, comorbidities, and hospital characteristics were evaluated. Post-operative opioid medications administered intravenously and orally during the hospital stay were identified from the data and converted to Morphine Milligram Equivalent per day (MME/d) for an evaluation and comparison during the index hospitalization. Descriptive statistics were used to report continuous and dichotomous variables. Dichotomous variables are reported as n (%) and continuous variables are reported as mean ± standard deviation (SD). Chi-square and T-tests were used as appropriate.

RESULTS

2399 patients who underwent AKA or BKA with peripheral vascular disease were evaluated. Sixty-three percent of the cohort was male, 67% Caucasian, and 42% married, and 58% had a Charlson index >3. The majority of patients had an average length of hospital stay of 5.7 days (M = 5.72, SD = 4.56). Patient groups that used significantly higher MME/d in the early postop period included: BKA (29.2 vs 20.7, p = 0.006), males (62.6 vs 54.0, p < 0.0001), Caucasians (64.3 vs 44.7, p < 0.0001), younger patients (69.6 vs 54.0, p < 0.0001), and those at non-training institutions (66.7 vs 56.7, p < 0.0001). Patients whose hospital stay was greater than 6 days were found to have increased opioid utilization likely secondary to index complications. For those discharged by post-operative day 7, the mean MME utilized on postop day 1 was 59.5 and decreased to a mean MME/d utilization prior to discharge of 17.6.

CONCLUSIONS

This analysis demonstrates that younger patients, males, patients with BKAs, and those who receive amputations for vascular disease at non-training institutions have higher post-operative opioid utilization during the hospital stay. At the time of discharge, patients utilized an average of 17.6 MME/d which equates to approximately three hydrocodone/acetaminophen 5/325 mg tablets per day. Based on these findings, vascular surgeons are likely over prescribing opioids at discharge and must be cognizant of appropriate dosing quantities. Prescriptions at discharge should reflect the daily utilization described from this analysis and tapered to avoid chronic utilization, overdose, and possible death.

Chronic post amputation pain: pathophysiology and prevention options for a heterogenous phenomenon

PURPOSE OF REVIEW

Chronic postamputation pain (cPAP) remains a clinical challenge, and current understanding places a high emphasis on prevention strategies. Unfortunately, there is still no evidence-based regimen to reliably prevent chronic pain after amputation.

RECENT FINDINGS

Risk factors for the development of phantom limb pain have been proposed. Analgesic preventive interventions are numerous and no silver bullet has been found. Novel techniques such as neuromodulation and cryoablation have been proposed. Surgical techniques focusing on reimplantation of the injured nerve might reduce the incidence of phantom limb pain after surgery.

SUMMARY

Phantom limb pain is a multifactorial process involving profound functional and structural changes in the peripheral and central nervous system. These changes interact with individual medical, psychosocial and genetic patient risk factors. The patient collective of amputees is very heterogeneous. Available evidence suggests that efforts should focus on prevention of phantom limb pain, since treatment is notoriously difficult. Questions as yet unanswered include the evidence-base of specific analgesic interventions, their optimal "window of opportunity" where they may be most effective, and whether patient stratification according to biopsychosocial risk factors can help guide preventive therapy.

Low-molecular-weight heparin is superior to unfractionated heparin in lowering the risk of venous thromboembolism after traumatic lower extremity amputation

BACKGROUND

Patients undergoing lower extremity amputation after trauma are at high risk of venous thromboembolism. Practice variations persist regarding the optimal pharmacologic agent for venous thromboembolism prophylaxis in this patient population. We aimed to compare the efficacy of unfractionated heparin versus low-molecular-weight heparin in preventing venous thromboembolism.

METHODS

Using the 2013 to 2019 American College of Surgeons Pediatric Trauma Quality Improvement Program database, all trauma patients (≥18) who underwent lower limb amputation and received venous thromboembolism thromboprophylaxis in the form of unfractionated heparin or low-molecular-weight heparin were included. We excluded patients who died within 24 hours of admission or those who received no thromboprophylaxis. The primary outcome was the rate of venous thromboembolism. Multivariable logistic regression was used to evaluate the independent relationship between the type of pharmacologic prophylaxis and the risk of venous thromboembolism.

RESULTS

A total of 4,103 patients who underwent lower extremity amputation were identified. Patients were primarily young (median age 43 years) with blunt injuries (83%). The overall rate of venous thromboembolism was 8.6%. Most (77%) patients received low-molecular-weight heparin-based prophylaxis. Compared with patients without venous thromboembolism, the venous thromboembolism cohort had a greater injury severity score (19 vs 13, P < .001), had more patients undergoing above-the-knee amputation (48% vs 36%, P < .001), and less frequently received low-molecular-weight heparin (64% vs 78%, P < .001). Multivariable analysis showed that low-molecular-weight heparin was associated with a significantly lower venous thromboembolism rate than unfractionated heparin (odds ratio: 0.65 [0.51-0.83], P < .001).

CONCLUSION

Thromboprophylaxis with low-molecular-weight heparin was found to be superior to unfractionated heparin in lowering the risk of venous thromboembolism among traumatic amputees and should be the preferred pharmacologic agent in this patient population prone to venous thromboembolism.

Evaluating the Role of Major Lower Extremity Amputation in Nonagenarians

OBJECTIVE

Elderly patients with critical limb ischemia are an especially frail and vulnerable group of patients. There is little literature investigating outcomes and resource utilization in nonagenarians undergoing major lower extremity amputation (MLEA). This study aims to elucidate the outcomes of this unique set of patients for whom amputation may often be considered a "palliative" intervention.

METHODS

Analyzing over 16,000 records from the Vascular Quality Initiative (VQI) database, we collected demographic, operative, and postoperative data on all patients who underwent an MLEA. We performed univariate analysis comparing nonagenarians to younger patients examining both short-term and long-term outcomes. Multimodel inference was used to analyze the effect of age on clinically meaningful outcomes: mortality and long-term living disposition.

RESULTS

With 392 nonagenarians and 16,349 patients under the age of 90, we found nonagenarians were less comorbid and less likely to have a prior bypass or amputation. Despite experiencing lower rates of reoperation and individual postoperative complications, nonagenarians suffered higher long-term mortality (46% vs. 22%, P < 0.0005) and were more likely to be living in a facility at follow-up (34% vs. 15%, P < 0.0005). Incorporating important demographic and clinical factors, multimodel inference demonstrated that, the nonagenarian age group was a critical predictor of nonhome living status (Akaike Importance weight 0.99).

CONCLUSIONS

Although nonagenarians were less comorbid than their younger counterparts and suffered fewer perioperative complications, MLEA leads to a poorer outcome with significant mortality and a higher likelihood of residing in a facility at long-term follow-up. These findings underscore the importance of frank goals of care discussions in nonagenarians considering major amputation.

Factors Associated With Amputation Following Ankle Fracture Surgery

Patients with diabetes mellitus (DM) are at increased risk of complications following ankle fracture surgery. Previous research suggests that patients of low socioeconomic status are at increased risk of amputation following orthopedic complications. The purpose of this research was to determine if low socioeconomic status increases risk of below-knee amputation (BKA) following ankle fractures among patients with DM. The National Inpatient Sample (NIS) was queried from 2010 to 2014 to identify 125 diabetic patients who underwent ankle fracture surgical fixation followed by BKA. Two cohorts (BKA vs no BKA) and a multivariate logistic regression model were created to compare the effects of independent variables, including age, sex, race, primary payer, median household income by ZIP code, hospital location/teaching status, and comorbidities. The most predictive variables for BKA were concomitant peripheral vascular disease (odds ratio [OR] 5.35, 95% confidence interval [CI] 3.51-8.15), history of chronic diabetes-related medical complications (OR 3.29, CI 2.16-5.01), age in the youngest quartile (OR 2.54, CI 1.38-4.67), and male sex (OR 2.28, CI 1.54-3.36). Patient race and median household income were not significantly associated with BKA; however, risk of BKA was greater among patients with Medicaid (OR 2.23, CI 1.09-4.53) or Medicare (OR 1.85, CI 1.03-3.32) compared to privately insured patients. Diabetic inpatients with Medicaid insurance are at over twice the odds of BKA compared to privately insured patients following ankle fracture. Furthermore, peripheral vascular diseases, uncontrolled diabetes, younger age, and male sex each independently increase risk of BKA.

A practical nomogram for predicting amputation rates in acute compartment syndrome patients based on clinical factors and biochemical blood markers

BACKGROUND

Amputation is a serious complication of acute compartment syndrome (ACS), and predicting the risk factors associated with amputation remains a challenge for surgeons. The aim of this study was to analyze the risk factors for amputation in patients with ACS and develop a nomogram to predict amputation risk more accurately.

METHODS

The study population consisted of 143 patients (32 in the amputation group and 111 in the limb preservation group) diagnosed with ACS. LASSO and multivariate logistic regression were used to screen predictors and create a nomogram. The model's accuracy was assessed by receiver operating characteristic (ROC) curves, C-index, calibration curves, and decision curve analysis (DCA).

RESULTS

The predictors included cause of injury, vascular damage, shock, and fibrinogen in the nomogram. The C-index of the model was 0.872 (95% confidence interval: 0.854-0.962), and the C-index calculated by internal validation was 0.838. The nomogram's area under the curve (AUC) was 0.849, and the calibration curve demonstrated a high degree of agreement between the nomogram's predictions and actual observations. Additionally, the DCA indicated good clinical utility for the nomogram.

CONCLUSION

The risk of amputation in ACS patients is associated with the cause of injury, vascular damage, shock, and fibrinogen. Our nomogram integrating clinical factors and biochemical blood markers enables doctors to more conveniently predict the risk of amputation in patients with ACS.

Tourniquet use for people with peripheral arterial disease undergoing major lower limb amputations

BACKGROUND

At least 7000 major lower limb amputations (MLLAs) are performed in the UK each year, 80% of which are due to peripheral arterial disease (PAD). Intraoperative blood loss can have a deleterious effect on patient outcomes, and its replacement with transfused blood is not without risk. Tourniquets can be used in lower limb surgical procedures to provide a bloodless surgical field, minimise intraoperative blood loss, and reduce perioperative blood transfusion requirements. Although their safety has been demonstrated in certain orthopaedic operations, their use among people with PAD undergoing MLLA remains controversial. Many clinicians are concerned about tourniquets potentially compromising perfusion of the stump and thereby impacting wound healing through direct tissue injury, damage to the arterial supply of the wound, or both.

OBJECTIVES

To assess the safety and effectiveness of tourniquet use in people undergoing MLLA for complications of PAD, specifically with regard to intraoperative blood loss, change in haemoglobin levels, transfusion rates, wound healing, need for revision surgery, and postoperative complications including mortality.

SEARCH METHODS

We searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase, and CINAHL databases and World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials registers from inception to 17 May 2022.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) comparing tourniquet use to no tourniquet use among people with PAD undergoing MLLA.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. Primary outcomes were intraoperative blood loss, fall in haemoglobin levels, and perioperative blood transfusion requirement. Secondary outcomes were primary wound-healing rates, stump revision rates, other postoperative complications defined as per Clavien-Dindo classification, and postoperative mortality at 30 days and at maximal follow-up. We used GRADE to assess the certainty of evidence for each outcome.

MAIN RESULTS

One RCT met our inclusion criteria, which was a prospective randomised blinded controlled trial conducted in Sheffield, UK in 2006. In total 64 participants undergoing transtibial amputation for non-reconstructable PAD were randomised to either tourniquet or no tourniquet to assess for intraoperative blood loss, fall in haemoglobin, transfusion requirement, wound healing, stump breakdown and revision. Ten participants were excluded postrandomisation (five from the tourniquet group and five from the no tourniquet group). The reported median volume of intraoperative blood loss was significantly less in the tourniquet group (255 mL (interquartile range (IQR) 150 to 572.5 mL))) compared to the control group (550 mL (IQR 255 to 1050 mL)) (P = 0.014). There was a significantly lower median drop in haemoglobin concentration in the tourniquet group (1.0 g/dL (IQR 0.6 to 2.4 g/dL)) compared to the control group (1.8 g/dL (IRQ 0 to 1.2 g/dL)) (P = 0.035). There was a significantly lower perioperative blood transfusion requirement in the tourniquet group (8 participants, 32%) compared to the control group (14 participants, 48%) (P = 0.047). There were no clear differences in wound breakdown, stump revision, primary wound healing at six weeks, postoperative complications (myocardial infarction, cardiac arrhythmias, pulmonary oedema), and death between groups. We assessed the one included study as at low risk of bias for sequence generation and blinding of outcome assessors; high risk of bias for incomplete outcome data and selective outcome reporting; and unclear risk of bias for allocation concealment, blinding of participants and personnel, and other sources of bias. We assessed the certainty of the evidence as low or very low due to risk of bias, small sample size, and the study being insufficiently powered for most outcomes.

AUTHORS' CONCLUSIONS

This review identified only one small historical RCT evaluating tourniquet use in MLLA. Tourniquets appeared to reduce intraoperative blood loss, drop in haemoglobin, and blood transfusion requirements following transtibial amputations for people with PAD. However, it is unclear whether tourniquets affect wound healing, stump revision rates, postoperative complications, or mortality. High-certainty evidence is required to inform clinical decision-making for the use of tourniquets in these patients.

The use of sodium-glucose co-transporter-2 inhibitors or glucagon-like peptide-1 receptor agonists versus sulfonylureas and the risk of lower limb amputations: a nation-wide cohort study

BACKGROUND

Numerous studies have investigated the potential association of sodium-glucose co-transporter-2 inhibitors (SGLT2-Is) with an increased risk of lower limb amputations (LLAs), but have produced conflicting results. Particularly studies comparing SGLT2-Is to glucagon-like peptide-1 receptor agonists (GLP1-RAs) seem to find a higher LLA risk with SGLT2-I use. This raises the question whether the results are driven by a protective GLP1-RA-effect rather than a harmful SGLT2-I-effect. GLP1-RAs could promote wound healing and therefore reduce the risk of LLAs, but the associations between both drug classes and LLA remain uncertain. Therefore, the aim of the current study was to investigate the risk of LLA and diabetic foot ulcer (DFU) with SGLT2-I use and GLP1-RA use versus sulfonylurea use.

METHODS

A retrospective population-based cohort study was conducted using data from the Danish National Health Service (2013-2018). The study population (N = 74,475) consisted of type 2 diabetes patients aged 18 + who received a first ever prescription of an SGLT2-I, GLP1-RA or sulfonylurea. The date of the first prescription defined the start of follow-up. Time-varying Cox proportional hazards models estimated the hazard ratios (HRs) of LLA and DFU with current SGLT2-I use and GLP1-RA use versus current SU use. The models were adjusted for age, sex, socio-economic variables, comorbidities and concomitant drug use.

RESULTS

Current SGLT2-I use was not associated with a higher risk of LLA versus sulfonylureas {adjusted HR 1.10 [95% confidence interval (CI) 0.71-1.70]}. Current GLP1-RA use, on the other hand, was associated with a lower risk of LLA [adjusted HR 0.57 (95%CI 0.39-0.84)] compared to sulfonylureas. The risk of DFU was similar to that with sulfonylureas with both exposures of interest.

CONCLUSION

SGLT2-I use was not associated with a higher risk of LLA, but GLP1-RAs with a lower risk of LLA. Previous studies reporting a higher risk of LLA with SGLT2-I use compared to GLP1-RA use might have been looking at a protective GLP1-RA effect, rather than a harmful SGLT2-I effect.

Surgical treatments for postamputation pain: study protocol for an international, double-blind, randomised controlled trial

BACKGROUND

Painful conditions such as residual limb pain (RLP) and phantom limb pain (PLP) can manifest after amputation. The mechanisms underlying such postamputation pains are diverse and should be addressed accordingly. Different surgical treatment methods have shown potential for alleviating RLP due to neuroma formation - commonly known as neuroma pain - and to a lesser degree PLP. Two reconstructive surgical interventions, namely targeted muscle reinnervation (TMR) and regenerative peripheral nerve interface (RPNI), are gaining popularity in postamputation pain treatment with promising results. However, these two methods have not been directly compared in a randomised controlled trial (RCT). Here, we present a study protocol for an international, double-blind, RCT to assess the effectiveness of TMR, RPNI, and a non-reconstructive procedure called neuroma transposition (active control) in alleviating RLP, neuroma pain, and PLP.

METHODS

One hundred ten upper and lower limb amputees suffering from RLP will be recruited and assigned randomly to one of the surgical interventions (TMR, RPNI, or neuroma transposition) in an equal allocation ratio. Complete evaluations will be performed during a baseline period prior to the surgical intervention, and follow-ups will be conducted in short term (1, 3, 6, and 12 months post-surgery) and in long term (2 and 4 years post-surgery). After the 12-month follow-up, the study will be unblinded for the evaluator and the participants. If the participant is unsatisfied with the outcome of the treatment at that time, further treatment including one of the other procedures will be discussed in consultation with the clinical investigator at that site.

DISCUSSION

A double-blind RCT is necessary for the establishment of evidence-based procedures, hence the motivation for this work. In addition, studies on pain are challenging due to the subjectivity of the experience and the lack of objective evaluation methods. Here, we mitigate this problem by including different pain evaluation methods known to have clinical relevance. We plan to analyse the primary variable, mean change in NRS (0-10) between baseline and the 12-month follow-up, using the intention-to-treat (ITT) approach to minimise bias and keep the advantage of randomisation. The secondary outcomes will be analysed on both ITT and per-protocol (PP). An adherence protocol (PP population) analysis will be used for estimating a more realistic effect of treatment.

TRIAL REGISTRATION

ClincialTrials.gov NCT05009394.

Utility of Removable Rigid Dressings in Decreasing Discharge Narcotic Use and Improving Ambulation Following Below-Knee Amputation

BACKGROUND

Lower extremity amputations are often associated with limited postoperative functionality and postoperative complications. Removable rigid dressings (RRDs) have been used following below-knee amputation (BKA) to improve limb maturation, decrease postoperative complications, reduce time to prosthesis casting, and limit conversion rates to above-knee amputation (AKA). We hypothesized that usage of RRD following BKA will correlate with decreased prescription narcotics required at discharge and improved ambulatory status at follow-up.

METHODS

A retrospective chart review was conducted to identify all patients who underwent BKA performed by the vascular surgery service at a large, acute care hospital between July 2016 and July 2021. Data collected included age, sex, body mass index, conversion to AKA, narcotic prescriptions at discharge, and ambulatory status at follow-up.

RESULTS

Between July 2016 and 2021, rate of conversion to AKA was significantly lower in patients who received an RRD (9.3%), as opposed to those who did not (41.5%) (P = 0.0002). Narcotic prescriptions at discharge, compared following conversion to morphine equivalents, were also significantly lower in the rigid dressing group compared to patients who did not receive the dressing (50.5 vs. 108.9 morphine eq/24 h, P = 0.0019). Furthermore, use of rigid dressing significantly improved ambulatory status at follow-up to 75.9% in RRD patients compared to 29.3% in patients with conventional dressing (P < 0.0001). This statistical significance persisted after all patients who were converted to AKA were removed from analysis (79.6% vs. 39.3% ambulatory, P = 0.000363). Multivariate analysis revealed that ambulatory status at follow-up was only associated with age more than 80 years (P = 0.042) and use of postoperative RRD (P = 0.001).

CONCLUSIONS

These findings support the utility of an RRD following BKA to reduce conversion to AKA, reduce narcotic dosages required at discharge, and improve ambulatory status at follow-up.

Concomitant Orthopedic Injury is the Strongest Predictor of Amputation in Extremity Vascular Trauma

BACKGROUND

Although the risk of extremity amputation related to an isolated vascular injury is low, it increases significantly with concomitant orthopedic injury. Our study aims to evaluate and quantify the impact of risk factors associated with trauma-related extremity amputation in patients with vascular injury. We sought to determine whether there are other potential predictors of amputation.

METHODS

A retrospective review of patients with extremity vascular injury presenting to a single level 1 academic trauma center between January 1, 2007, and December 31, 2018, was performed. All patients diagnosed with major vascular injury to the upper or lower extremity were included. Data on patient demographics, medical comorbidities, anatomic location of vascular injury, and the presence of soft tissue or orthopedic injury were collected. The main outcome measure was major amputation of the affected extremity. Major amputation included below-the-knee amputation, above-the-knee amputation, as well as any amputation of the upper extremity at or proximal to the wrist.

RESULTS

We identified 250 extremities with major vascular injury in 234 patients. Of these, 216 (86.4%) were male and 34 (13.6%) female. The mean age was 32.2 years (range 18-79 years) and mean follow-up was 6.9 (standard deviation: 3.3) years. Just over half of injuries, 130 (52.0%) involved the lower extremity. Forty extremities (29 lower and 11 upper), or 16.0%, of total injured extremities, required major amputation during the follow-up period. Concomitant orthopedic injury was present in 106 of 250 (42%) injured extremities. Using univariable logistic regression models, variables with a significant association with major amputation included older age, higher body mass index, blunt mechanism of injury, concomitant orthopedic injury, soft tissue injury, and nerve injury, and the need for fasciotomy (P < 0.05). In multivariable analyses, blunt mechanism of injury (odds ratio [OR] (confidence ratio {CI}): 6.51 (2.29, 18.46), P < 0.001) and concomitant orthopedic injury (OR [CI]: 7.23 [2.22, 23.55], P = 0.001) remained significant predictors of amputation.

CONCLUSIONS

Concomitant orthopedic injury and blunt mechanism in the setting of vascular injury are associated with a higher likelihood of amputation in patients with extremity vascular injury. Further development of a vascular extremity injury protocol may be needed to enhance limb salvage. Findings may guide patient discussion regarding limb-salvage decision-making.

Effect of a continuous perineural levobupivacaine infusion on pain after major lower limb amputation: a randomised double-blind placebo-controlled trial

OBJECTIVES

Randomised controlled trial of the effect of a perineural infusion of levobupivacaine on moderate/severe phantom limb pain 6 months after major lower limb amputation.

SETTING

Single-centre, UK university hospital.

PARTICIPANTS

Ninety patients undergoing above-knee and below-knee amputation for chronic limb threatening ischaemia under general anaesthesia. Exclusion criteria were patients having surgery under neuraxial anaesthesia; inability to operate a patient-controlled analgesia device or complete a Visual Analogue Scale; amputation for trauma or malignancy; or contraindication to levobupivacaine.

INTERVENTIONS

Either levobupivacaine 0.125% or saline 0.9% (10 mL bolus, infusion of 8 mL/hour for 96 hours) via a sciatic or posterior tibial nerve sheath catheter placed under direct vision during surgery.

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary outcome measure was the presence of phantom limb pain, residual limb pain and phantom limb sensations up to 6 months after amputation. Secondary outcome measures included early postoperative pain and morphine requirements after surgery.

RESULTS

Data from 81 participants were analysed; 6-month follow-up data were available for 62 patients. Pain and morphine requirements varied widely before and after amputation in both groups. The incidences of moderate/severe phantom limb pain, residual limb pain and phantom limb sensations were low from 6 weeks with no significant differences between groups in phantom limb pain at rest (OR 0.56, 95% CI 0.14 to 2.14, p=0.394) or movement (OR 0.58, 95% CI 0.15 to 2.21, p=0.425) at 6 months. Early postoperative pain scores were low in both groups with no between-group differences in residual limb pain or phantom limb sensations (rest or movement) at any time point. High postoperative morphine consumption was associated with worsening phantom limb pain both at rest (-17.51, 95% CI -24.29 to -10.74; p<0.001) and on movement (-18.54, 95% CI -25.58 to -11.49; p<0.001). The incidence of adverse effects related to the study was low in both groups: postoperative nausea, vomiting and sedation scores were similar, and there were no features of local anaesthetic toxicity.

CONCLUSIONS

Long-term phantom limb pain, residual limb pain and phantom limb sensations were not reduced significantly by perineural infusion of levobupivacaine, although the study was underpowered to show significant differences in the primary outcome. The incidence of phantom limb pain was lower than previously reported, possibly attributable to frequent assessment and early intervention to identify and treat postoperative pain when it occurred. There were large variations in postoperative pain scores, high requirements for analgesics before and after surgery and some problems maintaining recruitment and long -term follow-up. Knowledge of these potential problems should inform future research in this group of patients. Further work should investigate the association between perioperative morphine requirements and late phantom limb pain.

TRIAL REGISTRATION NUMBERS

EudraCT 2007-000619-27; ISRCTN68691928.

Post-amputation pain: Comparing pain presentations between adults with and without increased amputated-region sensitivity

OBJECTIVE

Among adults with persistent post-amputation pain, increased amputated-region pain sensitivity may reflect peripheral sensitization or indicate underlying central sensitization. To determine whether underlying central sensitization may contribute to increased pain sensitivity in this population, this study compared clinical signs and symptoms associated with central sensitization between adults with post-amputation pain who demonstrate or lack increased amputated-region sensitivity (as compared to reference data).

DESIGN

Cross-sectional.

SUBJECTS

Ninety-nine adults (60 with a unilateral, transtibial amputation and post-amputation pain, 39 pain-free controls with intact limbs).

METHODS

Participants underwent pain-pressure threshold testing of amputated-region and secondary (non-amputated region) sites and completed outcome measures assessing central sensitization symptoms (Patient-Reported Outcomes Measurement Information System® pain intensity and interference domains, Central Sensitization Inventory). Among the full sample, the presence and frequency of specific central sensitization symptoms were evaluated. Participants with post-amputation pain were then grouped based on whether normalized, amputated-region pain-pressure thresholds fell below (i.e., sensitive) or above (i.e., non-sensitive) the 25th percentile of sex-specific reference data. Between-group differences in normalized secondary-site sensitivity were evaluated using a multivariate analysis of variance; central sensitization symptom scores were compared using a Kruskal-Wallis test.

RESULTS

Noteworthy symptoms associated with central sensitization (e.g., fatigue, sleep disturbance, cognitive difficulty) were reported by 33%-62% of participants. Secondary-site pain sensitivity was greater among individuals with increased amputated-region sensitivity (n = 24) compared to peers without increased amputated-region sensitivity ([n = 36], mean difference > 1.33 standard deviation [SD], p < 0.001). Central sensitization symptom scores, however, were similar between groups (p > 0.187).

CONCLUSIONS

Participants with increased amputated-region sensitivity demonstrate generalized, secondary-site pain hypersensitivity, potentially indicating underlying central sensitization. Central sensitization symptom scores, however, were similar between groups, suggesting differences in physiological pain sensitivity may not manifest in subjective post-amputation pain descriptions.

Low Back Pain in People With Lower Limb Amputation: A Cross-Sectional Study

STUDY DESIGN

A cross-sectional study based on an online questionnaire.

OBJECTIVE

The aim was to investigate the prevalence and intensity of low back pain (LBP) in people with lower limb amputation (LLA) and to analyze the association factors that can influence the genesis of LBP.

SUMMARY OF BACKGROUND DATA

It is still unclear whether LBP is more prevalent in the amputated population than in its nonamputated counterpart. Given the multifactorial nature of LBP, it is necessary to explore possible factors that can influence its presence and intensity, to build a solid background to define a better rehabilitation pathway for the management of these people.

METHODS

The online questionnaire included six sections: informed consent of the study, demographic information, comorbid conditions, history of LLA, history of LBP, and acceptance of the amputation.

RESULTS

Between March and June 2021, 239 participants [mean age (SD): 49.2 (11.5); female 11%] completed the survey (response rate: 32%). From the results of this study, LBP in LLA showed a prevalence of 82% postamputation and 70% in the last year. A logistic regression with a backward method showed that participants who had problems in the not affected leg presented 1.58 (95% confidence interval: 0.70; 2.45) times higher odds to have LBP after the amputation.

CONCLUSION

This study shows that the prevalence of LBP in lower limb amputees appears to be higher than in the general population, with similar levels of pain intensity and frequency. The highest percentage of people with a sedentary lifestyle not practicing any kind of sports emphasizes the importance of educating this population on the importance of physical activity. New strategies to invest in the education of this population in terms of physical activity are needed.

LEVEL OF EVIDENCE

Level 4.

Artificial Intelligence Methodologies Applied to Technologies for Screening, Diagnosis and Care of the Diabetic Foot: A Narrative Review

Diabetic foot syndrome is a multifactorial pathology with at least three main etiological factors, i.e., peripheral neuropathy, peripheral arterial disease, and infection. In addition to complexity, another distinctive trait of diabetic foot syndrome is its insidiousness, due to a frequent lack of early symptoms. In recent years, it has become clear that the prevalence of diabetic foot syndrome is increasing, and it is among the diabetes complications with a stronger impact on patient's quality of life. Considering the complex nature of this syndrome, artificial intelligence (AI) methodologies appear adequate to address aspects such as timely screening for the identification of the risk for foot ulcers (or, even worse, for amputation), based on appropriate sensor technologies. In this review, we summarize the main findings of the pertinent studies in the field, paying attention to both the AI-based methodological aspects and the main physiological/clinical study outcomes. The analyzed studies show that AI application to data derived by different technologies provides promising results, but in our opinion future studies may benefit from inclusion of quantitative measures based on simple sensors, which are still scarcely exploited.

Single-Dose Radiation Therapy Without Additional Surgery as a Treatment for Heterotopic Ossification Developing After Transfemoral Amputation

ABSTRACT

Heterotopic ossification is the development of mature lamellar bone in soft tissues. Heterotopic ossification can occur in up to 23% of patients after amputation. Heterotopic ossification is often painful, causing significant dysfunction. While radiotherapy is used to prevent heterotopic ossification before formation, there is a dearth of literature on using radiotherapy to treat existing heterotopic ossification. This case report describes the use of late radiotherapy for the management of existing heterotopic ossification that developed after a transfemoral amputation. A 61-yr-old woman with peripheral artery disease of her bilateral lower limbs status post stenting and ultimately left transfemoral amputation was diagnosed with symptomatic heterotopic ossification limiting her function. Another surgery was not felt to be warranted. She was not improving with medical therapy and was prescribed 800 cGy in one fraction. After treatment, she experienced significant relief in her pain, allowing her to resume physical therapy and use of her prosthesis. There are no other published examples of using radiation alone for treatment of heterotopic ossification formation after transfemoral amputation without surgical revision of the bone formation. Our case shows possible utility in single-dose radiation as a treatment to prevent progression of heterotopic ossification, especially when limiting functional progress.

Surgical site infection after open lower extremity revascularization associated with doubled rate of major limb amputation

OBJECTIVE

Surgical site infection (SSI) after open lower extremity revascularization is a relatively common complication associated with increased hospital stays, graft infection, and in severe cases, graft loss. Although the short-term effects of SSI can be significant, it has not been considered a complication that increases major limb amputation. The purpose of this study was to determine the association of SSI with outcomes in patients undergoing surgical revascularization for peripheral arterial disease.

METHODS

We analyzed nationwide Vascular Quality Initiative (VQI) data from the infrainguinal bypass module from 2003 to 2017. The cohort included adults who underwent open lower extremity bypass for symptomatic peripheral arterial disease and had at least one follow-up record. Weighted Kaplan-Meier curves and Cox proportional hazards regression were used to assess the association between SSI and 1-year mortality and major limb amputation. Inverse-probability of treatment weights were used to account for differences in demographics and patient characteristics and allow for 'adjusted' Kaplan-Meier curves.

RESULTS

The analysis included 21,639 patients, and 1155 (5%) had a reported SSI within 30 days of surgery. Patients with SSI were more likely be obese (41% vs 30%), but there were no other clinically relevant differences between demographics, comorbidities, and bypass details. After weighting, patients with SSI were almost twice as likely to undergo major amputation by 6 months (hazard ratio, 1.84; 95% confidence interval, 1.07-3.17). The association with SSI and increased amputation rates persisted at 1 year. The association of SSI on amputation was no different based on preoperative Rutherford class (P = .91). The association between SSI and 1-year mortality rate was not statistically significant (hazard ratio, 1.15; 95% confidence interval, 0.91-1.46).

CONCLUSIONS

SSI is more common in obese patients, and patients who develop an SSI are observed to have a significantly increased rate of limb amputation after open lower extremity revascularization.

Local Environment Induces Differential Gene Expression in Regenerating Nerves

INTRODUCTION

Approximately 80% of amputations are complicated by neuromas. Methods for neuroma management include nerve translocation into bone and implantation into skeletal muscle grafts, which have also facilitated the development of regenerative neural interfaces to enable fixation of prosthetics with motor and sensory feedback. However, molecular-level differences between nerves in these environments have not been investigated. This study aimed to elucidate the physiology of regenerating nerves in different settings by assessing gene expression.

MATERIALS AND METHODS

New Zealand white rabbits underwent transfemoral amputation with sciatic nerve transposition into the femur or tacked to skeletal muscle. At 5 wk, ribonucleic acid (RNA) sequencing of samples of distal nerve terminating in bone or muscle and nerve of the contralateral limb (control) identified differentially expressed genes (DEGs) and biochemical pathways (α = 0.05).

RESULTS

Three samples of nerve housed in bone, four of nerve tacked to muscle, and seven naïve controls were analyzed. Relative to controls, nerve housed in bone had little within-group variation and 13,028 DEGs, and nerve tacked to muscle had dramatic within-group variation and 12,811 DEGs. These samples upregulated the following pathways: lysosome, phagosome, antigen processing/presentation, and cell adhesion molecule. Relative to nerve housed in bone, nerve tacked to muscle had 12,526 DEGs, demonstrating upregulation of pathways of B-cell receptor signaling, focal adhesion, natural killer-cell mediated cytotoxicity, leukocyte transendothelial migration, and extracellular matrix-receptor interactions.

CONCLUSIONS

Nerve housed in bone has a more predictable molecular profile than does nerve tacked to muscle. Thus, the intramedullary canal may provide a more reliable setting for neuroma prevention and neural interfacing.

Vascularized, Denervated Muscle Targets for Treatment of Symptomatic Neuromas in the Upper Extremity: Description of Operative Technique

Symptomatic neuromas of the upper extremity often cause persistent, debilitating pain that is resistant to medical management. Following upper extremity amputation, painful neuromas may disrupt rehabilitation efforts and pose a barrier to prosthetic use. Several surgical approaches have been attempted to treat neuromas, each of which suffers from limitations. We have developed a novel technique, the vascularized, denervated muscle target, that offers a compelling new option for primary prevention and secondary treatment of symptomatic neuromas of the upper extremity. Here, we provide a detailed description of our surgical technique as it is applied to neuromas of the upper extremity.

Use of Standardized Outcome Measures for People With Lower Limb Amputation: A Survey of Prosthetic Practitioners in the United States

OBJECTIVE

To assess the clinical resources available for the assessment of health outcomes in people with lower limb amputation and to understand barriers and facilitators associated with use of standardized outcome measures in clinical practice.

DESIGN

Cross-sectional survey.

SETTING

General community (online).

PARTICIPANTS

A volunteer sample of prosthetic practitioners was recruited through national professional organizations. Eligible participants were practitioners certified by a professional prosthetics organization and currently practicing as a prosthetist, prosthetist-orthotist, or prosthetic assistant.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

A custom-designed online survey on clinical use of patient-reported and performance-based standardized outcome measures to assess patients with lower limb amputation.

RESULTS

A total of 375 participants completed the survey. Most participants (79%) reported that they are encouraged or required to administer standardized outcome measures in their clinic or facility. Most participants reported that use of patient-reported and performance-based outcome measures are within their scope of practice (88%) and that they have the knowledge required for outcomes measurement (84%). Few participants agreed that outcomes measurement is standardized across the profession (30%). Most participants had access to small spaces and equipment for outcomes measurement, such as short hallways (65%-94%), stairs (69%), and tablets with wireless internet connection (83%). Most participants reported that they would be willing to spend between 5 (36% of participants) and 10 (43% of participants) minutes on self-reported surveys, and between 10 (41% of participants) and 20 (28% of participants) minutes on performance-based tests.

CONCLUSIONS

Outcomes measurement is encouraged or expected in contemporary prosthetic practice. Strategies to improve standardization and efficiency of administration are needed to facilitate routine use of outcome measures in clinical care.

Factors Related to Neuropathic Pain following Lower Extremity Amputation

BACKGROUND

Lower extremity amputations are common, and postoperative neuropathic pain (phantom limb pain or symptomatic neuroma) is frequently reported. The use of active treatment of the nerve end has been shown to reduce pain but requires additional resources and should therefore be performed primarily in high-risk patients. The aim of this study was to identify the factors associated with the development of neuropathic pain following above-the-knee amputation, knee disarticulation, or below-the-knee amputation.

METHODS

Retrospectively, 1565 patients with an average follow-up of 4.3 years who underwent a primary above-the-knee amputation, knee disarticulation, or below-the-knee amputation were identified. Amputation levels for above-the-knee amputations and knee disarticulations were combined as proximal amputation level, with below-the-knee amputations being performed in 61 percent of patients. The primary outcome was neuropathic pain (i.e., phantom limb pain or symptomatic neuroma) based on medical chart review. Multivariable logistic regression was performed to identify independent factors associated with neuropathic pain.

RESULTS

Postoperative neuropathic pain was present in 584 patients (37 percent), with phantom limb pain occurring in 34 percent of patients and symptomatic neuromas occurring in 3.8 percent of patients. Proximal amputation level, normal creatinine levels, and a history of psychiatric disease were associated with neuropathic pain. Diabetes, hypothyroidism, and older age were associated with lower odds of developing neuropathic pain.

CONCLUSIONS

Neuropathic pain following lower extremity amputation is common. Factors influencing nerve regeneration, either increasing (proximal amputations and younger age) or decreasing (diabetes, hypothyroidism, and chronic kidney disease) it, play a role in the development of postamputation neuropathic pain.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Risk, III.

Lower Extremity Amputations Among Veterans: Have Ambulatory Outcomes and Survival Improved?

OBJECTIVE

We hypothesize among patients undergoing lower extremity amputation, access to pre, and post operative rehabilitation services; as well as improved medical care, have led to higher rates of postoperative ambulation, and improved survival.

METHODS

Retrospective single center review of all major lower extremity amputations performed at the Greater Los Angeles Veterans Affairs Healthcare System from 2000 - 2020 stratified into multiyear cohorts. We abstracted demographics, operative indication, comorbidities, preoperative medical management, perioperative complications, discharge location, and pre- and postoperative ambulatory status. Odds of ambulation after amputation were analyzed using multivariate logistic regression. Survival was analyzed using multivariate logistic regression and Kaplan-Meier survival analysis. Multivariate logistic predictors were selected based on prior literature and clinical experience.

RESULTS

We identified 654 operations in our study, noting less amputations performed in the latest three cohort years as compared to the initial cohort (2000 - 2004). Patients undergoing below-knee amputations (BKA) had 2.7 times (p < 0.05) greater odds of postoperative ambulation and 86% (p < 0.05) increased odds of survival compared to above-knee amputations (AKA). The odds of ambulation increased by 8.8% (p < 0.05) for each consecutive study year. Ambulation post-amputation conferred 13.2 times (p < 0.05) greater odds of survival. The odds of survival in "emergent" operations decreased by 48% (p < 0.05) compared to an "elective" operation. For each additional comorbidity, the odds of survival decreased by 18% (p < 0.05). Patients with any perioperative complication had a 48% (p < 0.05) lower odds of survival. Kaplan Meier survival estimates demonstrated significant survival difference between patients by amputation level and postoperative ambulatory status (p < 0.05).

CONCLUSIONS

Ambulatory status following distal amputation has improved over time and is significantly associated with increased survival post-amputation. Patients undergoing a BKA or discharged home were most likely to ambulate postoperatively. Amputation level, preoperative comorbidities, and perioperative complications remain strong predictors of survival.

Amputation and infection are the greatest fears in patients with diabetes foot complications

AIMS

To determine the degree patients with diabetic foot ulcers, Charcot neuroarthropathy and neuropathic fractures and dislocations fear complications (death, dialysis, heart attack, stroke, blindness, diabetic foot infection, minor and major lower extremity amputation [LEA]) that can occur and to assess if there is a difference between fears of patients with diabetic foot ulcers, Charcot neuroarthropathy and neuropathic fractures and dislocations and diabetic patients without these complications.

METHODS

478 patients completed an eight question Likert scale survey. The study group was defined as non-infected foot ulcers, neuropathic fractures and Charcot neuroarthropathy.

RESULTS

Of the 478 patients, 121 (25.3 %) had diabetic foot ulcers, Charcot neuroarthropathy or neuropathic fractures and dislocations and 357 (74.7 %) did not. The study group had significantly higher odds of reporting extreme fear of foot infection (OR 2.8, 95 % CI 1.8-4.5), major LEA (OR 2.8, 95 % CI 1.8-4.4), minor LEA (OR 2.3, 95 % CI 1.5-3.5), blindness (OR 2.0, 95 % CI 1.3-3.2), dialysis (OR 2.0, 95 % CI 1.1-3.3), and death (OR 2.4, 95 % CI 1.4-4.2). In the study group highest rated fear measures were foot infection (3.71, SD 1.23), minor amputation (3.67, SD 1.45) and major amputation (3.63, SD 1.52). There were no significant differences in the mean fear of infection, minor amputation or major amputation.

CONCLUSION

Patients with diabetic foot ulcers, Charcot neuroarthropathy or neuropathic fractures and dislocations reported higher fear ratings of diabetes-related complications compared to those without these complications.

Scleroderma and Raynaud Phenomenon: The Cold Truth Regarding the Use of Operative Management

BACKGROUND

Raynaud phenomenon, with and without scleroderma, is a common vasospastic condition that manifests with extremity pain and skin discoloration. When conservative management fails, complications such as ischemia, ulceration, and gangrene may warrant surgical intervention. The purpose of this study was to determine the risk factors and use of surgical intervention in this population.

METHODS

A national insurance claims-based database with patient records from the Centers for Medicare and Medicaid Services was used for data collection. Patients with first diagnoses of Raynaud phenomenon, scleroderma, or both between 2005 and 2014 were identified. Primary outcomes included the presence of upper extremity amputation or vascular procedure, and history of amputation within 5 years of a vascular procedure. Secondary outcomes included hospital admissions, upper extremity wounds, and amputation within 1 year of diagnosis.

RESULTS

The Raynaud phenomenon, scleroderma, and Raynaud phenomenon with scleroderma cohorts consisted of 161,300, 117,564, and 25,096 patients, respectively. A diagnosis of both Raynaud phenomenon and scleroderma increased the odds of upper extremity amputation by 5.4-fold, vascular procedure by 4.8-fold, and amputation within 5 years of a vascular procedure by 1.5-fold. Patients with Raynaud phenomenon or scleroderma alone were 3.1 and 5.6 times less likely to undergo amputation within 5 years of a vascular procedure, respectively.

CONCLUSIONS

Patients with both Raynaud phenomenon and scleroderma have higher likelihoods of having upper extremity amputations, vascular procedures, and amputations following vascular procedures compared to each diagnosis alone. Vascular procedures are rarely being performed. Further research is necessary to establish a standard of care and determine whether early and more frequent intervention with vascular procedures can decrease amputation rates in this patient population.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Risk, II.

Percutaneous Transluminal Angioplasty for Below-the-Elbow Critical Hand Ischemia: A Systematic Review

PURPOSE

To perform a systematic review assessing the safety and efficacy of percutaneous transluminal angioplasty (PTA) for treatment of critical hand ischemia (CHI) due to below-the-elbow (BTE) obstructive arterial disease.

MATERIALS AND METHODS

MEDLINE and EMBASE systematic searches were performed from inception to December 2020 to identify studies assessing PTA for management of BTE obstructive arterial disease. Three independent reviewers performed abstract selection, data extraction, and quality assessment. The Newcastle-Ottawa Scale was used to assess individual study bias for non-randomized controlled trials.

RESULTS

Eight studies comprising 176 patients with obstructive BTE vessel disease were included. All studies had a score >5 on the Newcastle-Ottawa Scale, indicative of high quality. All studies used low-profile balloons (1.5-4 mm) for PTA of stenotic lesions or chronic total occlusions (CTOs). The weighted average technical success and clinical success rates were 89.3% (range = 82%-100%) and 69.9% (range = 19%-100%), respectively, at a mean follow-up of 29.7 ± 17.1 months. The short-term (<30 days) complication rate was low at 4.7% and most commonly included access site hematomas, pseudoaneurysms, and radial artery perforation or re-thrombosis. Nearly 20% of patients required an amputation, and most (96%) were minor (either distal phalanges or digits). Only 2 patients required above-wrist amputations. The primary and secondary patency rate at 5 years were 38% and 54%, respectively. The cumulative 5-year mortality rate was 33.1%.

CONCLUSIONS

PTA for CHI due to BTE obstructive arterial disease is feasible with a high technical success rate and a low short-term complication rate. Additional long-term comparative studies are required to unequivocally establish the clinical benefit of endovascular treatment compared with conservative management or surgical bypass.

Contribution of diabetes to amputations in sub-Sahara Africa: A systematic review and meta-analysis

Diabetes related amputations remain a major global problem, with devastating complications. We critically appraised relevant literature to quantify the prevalence of diabetes related amputations in sub-Saharan Africa (SSA). An electronic search was performed using the EMBASE and PubMed databases until 2020. Twenty-four out of 834 studies retrieved were included. The pooled prevalence of diabetic-related amputations was 36.9% (95%CI: 32.9%-40.8%). Complications of diabetes related amputations included infection, anaemia, foot deformity and mortality. The study revealed a substantial contribution of diabetes to the burden of amputations in SSA and suggests the need for further studies to assess how to reduce the incidence of diabetes, reduce the incidence of and or delay the progression of macro and microvascular complications of diabetes in SSA.

A systematic review of patient-reported outcome measures patients with chronic limb-threatening ischemia

Chronic limb-threatening ischemia (CLTI) causes significant morbidity with profound negative effects on health-related quality of life. As the prevalence of peripheral artery disease and diabetes continue to rise in our aging population, the public health impact of CLTI has escalated. Patient-reported outcome measures (PROMs) have become common and important measures for clinical evaluation in both clinical care and research. PROMs are important for the measurement of clinical effectiveness and cost effectiveness and for shared decision-making on treatment options. However, the PROMs used to describe the experience of patients with CLTI are heterogeneous, incomplete, and lack specific applicability to the underlying disease processes and diverse populations. For example, certain PROMs exist for patients with extremity wounds, and other PROMs exist for patients with pain, and still others exist for patients with vascular disease. Despite this multiplicity of tools, no single PROM encompasses all of the components necessary to describe the experiences of patients with CLTI. This significant unmet need is evident from both published reports and contemporary large-scale clinical trials in the field. In this systematic review, we review the current use of PROMs for patients with CLTI in clinical practice and in research trials and highlight the gaps that need to be addressed to develop a unifying PROM instrument for CLTI.

Population-Based Trends in Amputations and Revascularizations for Peripheral Artery Disease From 1990 to 2009

OBJECTIVE

To determine trends in amputations and revascularizations for peripheral artery disease (PAD) in a well-defined population.

METHODS

A population-based cohort study of Olmsted County, Minnesota, residents with PAD undergoing amputation or revascularization was conducted between January 1, 1990, and December 31, 2009. Population-level 5-year incidence trends for endovascular, open surgical, and hybrid revascularizations and major and minor amputations were determined. Limb-specific outcomes after revascularization, including major adverse limb events and amputation-free survival, were compared between initial surgical and endovascular or hybrid revascularization groups using Kaplan-Meier analysis.

RESULTS

We identified 773 residents who underwent 1906 limb-procedures, including 689 open revascularizations, 685 endovascular or hybrid revascularizations, and 220 major amputations. During the 20-year study period, the incidence of endovascular and hybrid revascularizations increased, whereas the incidence of open surgical revascularizations and major amputations decreased. Incidence of revascularizations for chronic limb-threatening ischemia (CLTI) did not change. Among residents with CLTI undergoing their first revascularization on a limb, endovascular revascularization was associated with more major adverse limb events and major amputations compared with surgical revascularization during the ensuing 15 years.

CONCLUSION

The rising incidence of endovascular and hybrid revascularizations and the decreasing incidence of open surgical revascularizations for PAD were associated with a decreasing incidence of major amputations in this population between 1990 and 2009, despite a stable incidence of revascularizations for CLTI. With more major adverse limb events and major amputations after endovascular revascularization, these trends suggest that additional emphasis should be placed on improving limb salvage efforts beyond just mode of revascularization.