Risk factors for failure of transmetatarsal amputation in diabetic patients: a cohort study

Above-ankle Reamputation and Mortality following Transmetatarsal Amputation in Diabetic and Nondiabetic Peripheral Artery Disease

The risk of above-ankle reamputation following a transmetatarsal amputation is around 30%. Patient selection may be crucial to achieve good outcomes, and to avoid futile operations and suffering. We are aware of no previous comparison between the two largest patient groups that undergo lower extremity amputations: patients with diabetes, and patients with non-diabetic peripheral artery disease. Patients with diabetes or nondiabetic peripheral artery disease who had undergone a transmetatarsal amputation from 2004 to 2018 at our institution were included. Patient characteristics and perioperative details were analyzed retrospectively. Subjects with diabetes were compared with subjects with nondiabetic peripheral artery disease regarding above-ankle reamputation, reamputation level, and mortality. Five-hundred-and-sixty transmetatarsal amputations in 513 subjects were included. The majority of transmetatarsal amputations (86%) occurred in diabetic subjects. Subjects with non-diabetic PAD had a higher risk of above-ankle reamputation (p = .008), and death (p < .001). At the time of data collection, only multiple-ray amputation (vs. single-ray) was an independent risk factor for above-ankle reamputation. Only age, medical comorbidity in general, and chronic heart failure were independent risk factors of death. To our knowledge, this study is the first to report marked differences in above-ankle reamputation rates and mortality following transmetatarsal amputation, comparing diabetics with non-diabetic patients with peripheral artery disease. However, the differences may be attributed to non-diabetics being older, having more medical comorbidities, and having more advanced foot ulcers at the time of transmetatarsal amputation. In patients exhibiting several of these risk factors, transmetatarsal amputation may be futile.

Morbidity and Mortality of the Transmetatarsal Amputation: A Comparative NSQIP Analysis

The objective of this investigation was to compare the morbidity and mortality of transmetatarsal amputation to other frequently performed surgical procedures utilizing a large US database. The American College of Surgeons National Surgical Quality Improvement Program (NSQIP) database was interrogated for the purposes of this investigation. We initially extracted data related to the Current Procedural Terminology (CPT) code 28805 (amputation, foot; transmetatarsal) and the variable labels "estimated probability of morbidity" and "estimated probability of mortality." We subsequently performed a CPT code search for those procedures occurring at a frequency greater than 10,000 in the database, and additionally extracted data for estimated probability of morbidity and estimated probability of mortality for these procedures. This resulted in identification of 17 additional procedures. CPT code 28805 was associated with the highest estimated probability of morbidity of the cohort (0.1360 ± 0.0669), and this demonstrated statistical significance higher than all other CPT codes (p < .001). CPT code 28805 was associated with the second-highest estimated probability of mortality of the cohort (0.0327 ± 0.0596). This demonstrated statistical significance less than that of CPT code 27245 (0.0327 ± 0.0596 vs 0.0547 ± 0.0661; p < .0001), but statistical significance higher than all other CPT codes (p<0.001). The results of this investigation indicate that transmetatarsal amputation carries a substantial risk for morbidity and mortality in comparison to other commonly performed surgical procedures.

A Preliminary Look at the Macrovascular System for Transmetatarsal Amputation Success

OBJECTIVE

Transmetatarsal amputation (TMA) is a commonly used level of amputation that preserves most of the foot's function and independence. However, many TMAs fail, and patients go onto higher amputations. The primary endpoint of this study is to determine if source artery occlusions are correlated with TMA flap failure.

METHODS

A total of 82 patients with TMAs were retrospectively reviewed for healing rates between 2009 and 2019 at a single center. Forty-five of the patients had an angiogram, which was analyzed for source artery and overall TMA failure. Of the initial 82 patients, a cohort of 12 had documentation of specific flap failure and an angiogram performed. This cohort of 12 patients was used for correlation of flap failure with source artery occlusion.

RESULTS

Overall, the TMA healing rate was 45.28%. No correlation was noted between a specific source artery occlusion and overall TMA failure. However, a moderate positive correlation was seen with dorsalis pedis artery and peroneal artery occlusions and dorsal flap failure. No correlation was seen with the posterior tibial artery and plantar flap failure. A moderate negative correlation was seen with peroneal artery occlusion and plantar flap failure.

CONCLUSIONS

The authors concluded that retrograde flow through the angiosome principle is what allowed for successful outcomes in TMAs. Physicians are urged to carefully plan, dissect, and preserve these vessels to help prevent TMA flap failure, especially in patients with vascular risk or disease.

Risk Factors for a Failed Transmetatarsal Amputation in Patients with Diabetes

BACKGROUND

Transmetatarsal amputation (TMA) is a well-recognized limb-salvage procedure, often indicated for the treatment of diabetic foot infections. Currently, there is no widespread agreement in the literature with regard to the factors associated with failure of TMA. This study aimed to define risk factors for the failure of TMA, defined as below-the-knee or above-the-knee amputation, in patients with diabetes.

METHODS

This retrospective cohort study included 341 patients who underwent primary TMA. Patients who had a revision to a higher level (the failed TMA group) were compared with those who did not have failure of the initial amputation (the successful TMA group).

RESULTS

This study showed a higher frequency of renal impairment, defined as a high creatinine level and/or a previous kidney transplant or need for dialysis, in the failed TMA group (p = 0.002 for both). Furthermore, a Charlson Comorbidity Index (CCI) threshold value of 7.5 was identified as the optimal predictive value for failure of TMA (p = 0.002), and patients with a CCI of >7.5 had a median time of 1.13 months until the initial amputation failed.

CONCLUSIONS

TMA is associated with a high risk of revision. CCI may be used as a preoperative selection criterion, as 71.8% of patients with a CCI of >7.5 had failure of the TMA.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Recurrent diabetic foot ulcers: Results of a maximal multidisciplinary approach including reconstructive foot/ankle surgery

The diabetic foot ulcer (DFU) and Charcot Neuroarthropathy (CN) are serious complications of diabetes mellitus in which wound closure is complex to achieve. Treating recurrent DFU in patients with a combination of infection, ischemia, and deformities is extremely challenging and this group of patients has a very poor outcome. This case series describes the outcomes of patients with a recurrent DFU and CN, with a mean SINBAD score of 4 and of which 40% had a TCS of D3, using a multidisciplinary protocol that includes reconstructive foot and ankle surgery. In 24/35 (69%) of patients, wound closure was achieved after a mean of 75 days postoperatively. The mean ulcer-free period was 358 days. The mean number of interventions was 6.7 (range 3-9). Post treatment 27/35 (77%) of patients was mobile, without additional amputation or ulcer recurrence. This study shows that wound closure and a long ulcer-free period can be achieved in patients with a DFU and CN and its multifactorial underlying diseases when treated in a multidisciplinary team, including reconstructive foot and ankle surgery.

Transmetatarsal amputations in patients with diabetes mellitus: A contemporary analysis from an academic tertiary referral centre in a developing community

Transmetatarsal amputation (TMA) involves the surgical removal of the distal portion of metatarsals in the foot. It aims to maintain weight-bearing and independent ambulation while eliminating the risk of spreading soft tissue infection or gangrene. This study aimed to explore the risk factors and surgical outcomes of TMA in patients with diabetes at an academic tertiary referral center in Jordan. Medical records of all patients with diabetes mellitus who underwent TMA at King Abdullah University Hospital, Jordan, between January 2017 and January 2019 were retrieved. Patient characteristics along with clinical and laboratory findings were analyzed retrospectively. Pearson’s chi-square test of association, Student’s t-test, and multivariate regression analysis were used to identify and assess the relationships between patient findings and TMA outcome. The study cohort comprised 81 patients with diabetes who underwent TMA. Of these, 41 (50.6%) patients achieved complete healing. Most of the patients were insulin-dependent (85.2%). Approximately half of the patients (45.7%) had severe ankle-brachial index (ABI). Thirty patients (37.1%) had previous revascularization attempts. The presence of peripheral arterial disease (P<0.05) exclusively predicted poor outcomes among the associated comorbidities. Indications for TMA included infection, ischemia, or both. The presence of severe ABI (≤0.4, P<0.01) and a previous revascularization attempt (P<0.05) were associated with unfavorable outcomes of TMA. Multivariate analysis that included all demographic, clinical, and laboratory variables in the model revealed that insulin-dependent diabetes, low albumin level (< 33 g/L), high C-reactive protein level (> 150 mg/L), and low score of Laboratory Risk Indicator for Necrotizing Fasciitis (LRINEC, <6) were the main factors associated with poor TMA outcomes. TMA is an effective technique for the management of diabetic foot infection or ischemic necrosis. However, attention should be paid to certain important factors such as insulin dependence, serum albumin level, and LRINEC score, which may influence the patient’s outcome.

The Effect of Remnant Metatarsal Parabola Structure on Transmetatarsal Amputation Primary Healing and Durability

Although generally considered to be both a durable and functional procedure for limb preservation, the transmetatarsal amputation (TMA) has high rates of complication, failure, revisional operation, and progression to more proximal amputation. The objective of this investigation was to determine the effect of remnant metatarsal parabola structure on healing outcomes following TMA. A retrospective chart review was performed of subjects undergoing a complete TMA with primary closure. We considered 4 patterns of remnant metatarsal parabola structure. TMA pattern type 1 was a normal parabola with the remnant second metatarsal extending furthest distally and slightly longer than the remnant first and third metatarsals with a gradual lateral taper. TMA pattern type 2 was the first metatarsal remnant extending furthest distally with a gradual lateral taper. TMA pattern type 3 was a relatively long fifth metatarsal remnant without the presence of a gradual lateral taper. And TMA pattern type 4 was a relatively short first metatarsal remnant with a relatively long second metatarsal with a gradual lateral taper. Seventy-three transmetatarsal amputations in 73 subjects met selection criteria. Thirty-nine (53.4%) amputations healed primarily at 90 days. No statistically significant differences were observed between groups with respect to the 90-day primary healing rate (p = .571) or 1-year ambulation rate without wound recurrence or reoperation (p = .811). These results might indicate that the remnant metatarsal structure does not have an effect on transmetatarsal amputation outcome. It is our hope that these results add to the body of knowledge and lead to further investigations into outcomes of limb preservation surgical interventions.

Foot Osteomyelitis Location and Rates of Primary or Secondary Major Amputations in Patients With Diabetes

BACKGROUND

Diabetic foot osteomyelitis (DFO) often leads to amputations in the lower extremity. Data on the influence of the initial anatomical DFO localization on ultimate major amputation are limited.

METHODS

In this retrospective analysis, 583 amputation episodes in 344 patients (78 females, 266 males) were analyzed. All received a form of amputation in combination with antibiotic therapy. A multivariate logistic regression analysis with the primary outcome "major amputation" defined as an amputation above the ankle joint was performed. The association of risk factors including location of DFO, coronary artery disease, peripheral artery disease, neuropathy, nephropathy, and Charcot neuro-osteoarthropathy was analyzed.

RESULTS

Among 583 episodes, DFO was located in the forefoot in 512 (87.8%), in the midfoot in 43 (7.4%), and in the hindfoot in 28 episodes (4.8%). Overall, 53 of 63 (84.1%) major amputations were performed because of DFO in the setting of peripheral artery disease as primary indication. Overall, limb loss occurred in 6.1% (31/512) of forefoot, 20.9% (9/43) of midfoot, and 46.4% (13/28) of hindfoot DFO. Among these, 22 (41.5%) were performed as the primary treatment, whereas 31 (58.5%) followed previously failed minor amputations. Among this latter group of secondary major amputations, the DFO was localized to the forefoot in 23 of 583 (3.9%), the midfoot in 4 of 583 (0.7%) and the hindfoot in 4 of 583 (0.7%). In multivariate logistic regression analysis, initial hindfoot localization was a significant factor (P < .05), whereas peripheral artery disease, smoking, and a midfoot DFO were not found to be risk factors.

CONCLUSION

In our retrospective series, the frequency of limb loss in DFO increased with more proximal initial foot DFO lesions, with almost half of patients losing their limbs with a hindfoot DFO.

LEVEL OF EVIDENCE

Level IV, retrospective cohort study.

Are Transmetatarsal Amputations a Durable Limb Salvage Option? A Single-Institution Descriptive Analysis

In limb and life-threatening diabetic foot infections, transmetatarsal amputations are often indicated as a limb salvage procedure. The aim of this study is to analyze the long-term durability of initially successful transmetatarsal amputations in the diabetic population. We defined a successful transmetatarsal amputation as one which had clinical healing 1 year after surgery. A retrospective review of transmetatarsal amputations completed at our institution over an 11-year period was performed. We identified 83 amputations that met inclusion criteria. The mean follow-up was 4 years. The mean time to surgical healing was 109.8 days. After successfully healing the transmetatarsal amputation the long-term outcomes were analyzed. Re-ulcerations occurred in 44% of the transmetatarsal amputations a mean of 15 months after surgical healing. Patients who re-ulcerated were noted to be significantly younger (p value 0.02) with a significantly higher preprocedure hemoglobin A1c (p value < .001). Additional procedures after successful healing included 13 (15.66%) revision surgeries and 12 (14.46%) more proximal amputations. While transmetatarsal amputations remain a viable and durable limb preserving surgery, all patients who have undergone a transmetatarsal amputation should be monitored lifelong as they remain at risk for re-ulceration and more proximal amputation.

Operative Ankle Fractures in Complicated Diabetes: Outcomes of Prolonged Non-Weightbearing

Diabetes increases the risk of developing postoperative complications such as superficial and deep infection, wound dehiscence, and revisional surgery. Prolonged non-weightbearing and/or augmented fixation may reduce postoperative complications in complicated diabetic ankle fractures. This study's purpose was to compare the development of postoperative infection, wound dehiscence, and revisional surgery in complicated diabetic ankle fractures with respect to weightbearing status. We hypothesized that fewer complications would occur in patients with prolonged non-weightbearing. Medical records of 90 surgically treated complicated diabetic ankle fractures were retrospectively reviewed for postoperative radiographs, weightbearing status, and complications. Complicated diabetes was defined as HbA1c ≥ 8% within 1 year of surgery. Twenty-four out of 90 patients had prolonged non-weightbearing status, which was defined as ≥ 8 weeks of non-weightbearing postoperatively. Twelve out of 90 patients had augmented fixation, which was defined as standard open reduction and internal fixation plus ≥ 2 tetra-cortical or > 2 tri-cortical syndesmotic screws with medial plate, external fixation, or other combination. Thirty-three out of 90 patients (36.7%) patients developed complications postoperatively. Patients with prolonged non-weightbearing had less complications (29.2% vs 39.4%, p = .37) and larger HbA1c values compared with early weightbearing patients (10.0 vs 9.3, p = .04). A one-unit increase in creatinine value (mg/dL) revealed a 3.15-fold increase in development of complications (95% confidence interval 1.29-7.65, p = .01). Although not statistically significant, complicated diabetic ankle fractures treated with prolonged non-weightbearing had less complications postoperatively except for ankle Charcot. Creatinine can be utilized as an independent risk factor for postoperative complications in this population.

Functional and Patient-reported Outcomes following Transmetatarsal Amputation in High-risk Limb Salvage Patients

Background

Transmetatarsal amputation (TMA) is performed in patients with nonhealing wounds of the forefoot. Compared with below-knee amputations, healing after TMA is less reliable, and often leads to subsequent higher-level amputation. The aim of this study was to evaluate the functional and patient-reported outcomes of TMA.

Methods

A retrospective review of patients who underwent TMA from 2013 to 2021 at our limb-salvage center was conducted. Primary outcomes included postoperative complications, secondary proximal lower extremity amputation, ambulatory status, and mortality. Univariate and multivariate analyses were performed to evaluate independent risk factors for higher-level amputation after TMA. Patient-reported outcome measures for functionality and pain were also obtained.

Results

A total of 146 patients were identified. TMA success was achieved in 105 patients (72%), and 41 patients (28%) required higher-level amputation (Lisfranc: 31.7%, Chopart: 22.0%, below-knee amputations: 43.9%). There was a higher incidence of postoperative infection in patients who subsequently required proximal amputation (39.0 versus 9.5%, P < 0.001). At mean follow-up duration of 23.2 months (range, 0.7-97.6 months), limb salvage was achieved in 128 patients (87.7%) and 83% of patients (n = 121) were ambulatory. Patient-reported outcomes for functionality corresponded to a mean maximal function of 58.9%. Pain survey revealed that TMA failure patients had a significantly higher pain rating compared with TMA success patients (P = 0.016).

Conclusions

TMA healing remains variable, and many patients will eventually require a secondary proximal amputation. Multi-institutional studies are warranted to identify perioperative risk factors for higher-level amputation and to further evaluate patient-reported outcomes.

Avoiding the Deep Plantar Arterial Arch in Transmetatarsal Amputations: A Cadaver Study

BACKGROUND

The deep plantar arterial arch (DPAA) is formed by an anastomosis between the deep plantar artery and the lateral plantar artery. The potential risk of injury to the DPAA is concerning when performing transmetatarsal amputations, and care must be taken to preserve the anatomy. We sought to determine the positional anatomy of the DPAA based on anatomical landmarks that could be easily identified and palpated during transmetatarsal amputation.

METHODS

In an effort to improve our understanding of the positional relationship of the DPAA to the distal metatarsal parabola, dissections were performed on 45 cadaveric feet to measure the location of the DPAA with respect to the distal metatarsal epiphyses. Images of the dissected specimens were digitally acquired and saved for measurement using in-house-written software. The mean, SD, SEM, and 95% confidence interval were calculated for all of the measurement parameters and are reported on pooled data and by sex. An independent-samples t test was used to assess for sex differences. Interrater reliability of the measurements was estimated using the intraclass correlation coefficient.

RESULTS

The origin of the DPAA was located a mean ± SD of 35.6 ± 3.9 mm (95% confidence interval, 34.5-36.8 mm) proximal to the perpendicular line connecting the first and fifth metatarsal heads. The average interrater reliability across all of the measurements was 0.921.

CONCLUSIONS

This study provides the positional relationship of the DPAA with respect to the distal metatarsal parabola. This method is easily reproducible and may assist the foot and ankle surgeon with surgical planning and approach when performing partial pedal amputation.

A Comparison of Adverse Short-Term Outcomes Following Forefoot Amputation Performed on an Inpatient Versus Outpatient Basis

The objective of this investigation was to evaluate short-term adverse outcomes following forefoot amputation with a specific comparison between those procedures performed on an inpatient versus outpatient basis. The 2018 American College of Surgeons National Surgical Quality Improvement Program database was interrogated to select those subjects with a 28805 current procedural terminology code (amputation, foot; transmetatarsal) that underwent the procedure with "all layers of incision (deep and superficial) fully closed." This resulted in 326 subjects who underwent the procedure on an inpatient basis and 72 subjects who underwent the procedure on an outpatient basis. Results of the primary outcome measures found no significant differences between groups with respect to the development of a superficial surgical site infection (5.8% vs 5.6%; p = .950), deep incisional infection (3.4% vs 5.6%; p = .380), or wound disruption (3.4% vs 6.9%; p = .163). Additionally, no significant differences were observed between groups with respect to unplanned reoperations (15.6% vs 12.5%; p = .500) or unplanned hospital readmissions (21.8% vs 23.6%; p = .957). The results of this investigation demonstrate no difference in short-term adverse outcomes following the performance of forefoot amputation with primary closure when the procedure is performed on an inpatient or outpatient basis. We hope that this information is utilized in future investigations specifically examining this clinical scenario as it relates to hospital admission criteria related to lower extremity tissue loss, length of hospital stay considerations, the timing of partial foot amputation following revascularization, and the economics of limb preservation.

Lower extremity reamputation in people with diabetes: a systematic review and meta-analysis

In this study, we determined the reamputation-free survival to both limbs and to the contralateral limb only following an index amputation of any-level and assessed whether reamputation rates have changed over time. We completed a systematic search using PubMed and screened a total of 205 articles for data on reamputation rates. We reported qualitative characteristics of 56 studies that included data on reamputation rates and completed a meta-analysis on 22 of the studies which enrolled exclusively participants with diabetes. The random-effects meta-analysis fit a parametric survival distribution to the data for reamputations to both limbs and to the contralateral limb only. We assessed whether there was a temporal trend in the reamputation rate using the Mann-Kendall test. Incidence rates were high for reamputation to both limbs and to the contralateral limb only. At 1 year, the reamputation rate for all contralateral and ipsilateral reamputations was found to be 19% (IQR=5.1%-31.6%), and at 5 years, it was found to be 37.1% (IQR=27.0%-47.2%). The contralateral reamputation rate at 5 years was found to be 20.5% (IQR=13.3%-27.2%). We found no evidence of a trend in the reamputation rates over more than two decades of literature analyzed. The incidence of lower extremity reamputation is high among patients with diabetes who have undergone initial amputations secondary to diabetes, and rates of reamputation have not changed over at least two decades.

Transmetatarsal Amputation Outcomes When Utilized to Address Foot Gangrene and Infection: A Retrospective Chart Review

A transmetatarsal amputation (TMA) is a widely utilized procedure to address foot gangrene and infection. Although a common procedure, so too are the associated complications. The purpose of this review was to evaluate TMA healing and to explore if there were associated variables correlating with healed vs. failed to heal TMA sites. To do so, the Medical Department Orthopaedics Division Electronic Database, West Virginia University, College of Medicine was retrospectively searched to identify all cases of TMAs (CPT code 28805) during the period of January 2011 through June 2019, and those variables that might impact TMA healing. Then both univariate and multivariable logistic regression analyses were performed to investigate the associations between these variables and TMA healing, and sensitivity analyses were also conducted to determine if the results resisted the influence of one unmeasured confounder. There were 39 patients (41 procedures) who would undergo a TMA. The mean average patient age was 53 (range 29-73) years old. The median postoperative follow-up period was 617 (range 199-3632) days. TMA mortality data revealed 0 deaths at 30 days, 2 (5.1%) at 1 year, 8 (20.5%) at 5 years. In our study, 29 (70.7%) of the TMAs would achieve primary healing at a median of 31 (range 16-253) days. When comparing the TMA healed group to the failed to heal group the following independent variables were considered: diabetes mellitus, HgA1c >8%, neuropathy, peripheral arterial disease, chronic kidney disease, active smoking status, previous surgery, and a clean margin metatarsal bone pathology specimen positive for osteomyelitis. Of the aforementioned, only neuropathy (odds ratio [OR] = 0.056, 95% confidence interval [CI] = 0-0.501, p = .0062) and positive bone margin (OR = 0.144, 95% CI = 0.022-0.835, p = .0385) were found to be significant in univariate logistic regression analysis. In multivariable logistic regression analyses where the potential confounders age, gender, and body mass index were accounted for, of the 8 independent variables of interest, only neuropathy (OR = 0.037, 95% CI = 0-0.497, p = .0036) remained significantly associated with the healing status. Neuropathy was present in 17 (58.6%) of the healed TMAs and in 12 (100%) of the failed to heal TMAs. However, the positive bone margin failed to reach statistical significance (OR = 0.079, 95% CI = 0-1.39, p = .1331). Results from another multivariable logistic regression model where a quadratic term for age was added revealed that positive bone specimen correlated with the TMA healing status with significance (OR = 0.051, 95% CI = 0.001- 0.560, p = .0404). A positive clean margin bone specimen was found in 3 (10.3%) of the healed TMAs and in 4 (44.4%) of the failed to heal TMAs. The sensitivity analysis where current ulceration was used as an unmeasured confounder indicated that the results regarding the association between neuropathy or positive bone margin and TMA healing, though inconclusive, resisted the influence of this unmeasured confounder. Hopefully these findings will be a beneficial addition to the current TMA literature and as such, further assist with informed surgical decision making.

Transmetatarsal amputation: A 12 year retrospective case review of outcomes

BACKGROUND

Diabetic foot pathology has rapidly increased, presenting a vast economic burden with severe implications for patients. Establishing effective limb salvage techniques such as transmetatarsal amputation is essential to offer viable alternatives to major limb amputation in severe foot infection, where outcomes are variable and mortality rates high.

METHODS

A retrospective review of outcomes was performed on patients who underwent TMA at a single United Kingdom hospital between 2005-2017. Healing rate and time to healing, mortality, duration of hospital admission and incidence of revision surgery was evaluated. Forty-seven patients had 54 TMA's by the Podiatric Surgery team. Data was assessed for Mean (SD) and Median. The impact of co-morbidities was considered and the perioperative and surgical management reviewed to identify techniques which may improve outcomes.

RESULTS

A 78% healing rate was achieved. Six patients (11%) died before healing. The aremaining 11% did not heal and resulted in major limb amputation. No further surgery to the same foot was required after the TMA healed. A Median healing time of 83 days was identified and the Median duration of hospital admission was 24 days. Adjunctive wound care products may to have a positive impact on these factors. Five-year mortality was 43%, and demonstrated an association with renal and/or vascular pathology. All patients had diabetes, with many also having Peripheral Vascular Disease (PVD). Almost all TMA's failing to heal had PVD. The presence and severity of renal disease also seemed to have a negative impact on wound healing.

CONCLUSION

Positive healing and mortality rates with low need for revision surgery support TMA to be an effective alternative to major limb amputation. Adjunctive agents may have a positive impact on wound healing and length of hospital admission. Skilled surgical technique and Multidisciplinary work is essential for positive long-term outcomes and cost-effective care.

Revision After Total Transmetatarsal Amputation

Total transmetatarsal amputation (TMA) can be an option for foot salvage in gangrene, sepsis, or infected necrosis. However, the literature concerning predictive outcome factors and bacterial sampling is scarce. To identify potential associations between revision surgery and underlying bacteria or other preoperative selection criteria, we reviewed all patients with TMA who were treated at our institution. We compared the patients with remissions with surgical revisions. Among 96 adult patients with TMA (105 amputations), 42 required a revision surgery (40%), 18 had a further minor proximal surgical reamputation (17%) and 18 had a major proximal surgical reamputation (14%). In group comparisons, a previous infection with Staphylococcus aureus was protective with a lower revision risk (4/26 with revision surgery vs 22/26 without revisions; p = .03). This was the opposite for postoperative persistent soft tissue or bone infections (p < .01) and delayed wound healing (p < .01), which were positively associated with a revision risk. The American Society of Anesthesiologists Score, sex, age, body mass index, diabetes, polyneuropathy, chronic renal failure, dialysis, peripheral arterial disease, smoking status, and antibiotic regimen did not influence this revision risk. These results must be interpreted cautiously because no multiple variable calculations could be conducted as a result of the paucity of cases and confounding could not be evaluated sufficiently. TMA is an option to prevent major amputations, but it may be associated with a subsequent revision risk of 40% in adult patients. In our cohort study, persistent postamputation infection and delayed wound healing were associated with revision. However, no preoperative selection criteria were found that lead to revision surgery except for an infection with Staphylococcus aureus, which protected against revision surgery.

Renal Function as a Predictor of Early Transmetatarsal Amputation Failure

Chronic kidney disease (CKD) is a major concern in patients with foot disease because it is associated with high rates of neuropathy, peripheral vascular disease, and poor wound healing. The purpose of this study was to evaluate renal dysfunction as a risk factor for reamputation after initial transmetatarsal amputation (TMA). Patients who underwent a TMA were retrospectively identified in the American College of Surgeons National Surgical Quality Improvement Program database. Of 2018 patients, reamputation after TMA occurred in 4.4%. End-stage renal disease (ESRD) was associated with 100% increased odds of TMA failure (adjusted odds ratio [OR] = 2.00; 95% CI = 1.10, 3.52), 128% increased odds of major amputation (adjusted OR = 2.28; 95% CI = 1.27, 3.96), and 182% increased odds of 30-day mortality (adjusted OR = 2.82; 95% CI = 1.69, 4.64). In addition, white blood cell count >10 000/mm³ and deep infection at the time of surgery were independently associated with TMA failure. In conclusion, severe renal dysfunction is associated with TMA failure in the short-term, perioperative period. There was no incremental increase in risk of TMA failure with worsening level of renal function before ESRD. A multidisciplinary approach should be implemented in patients with CKD to prevent foot-related pathologies that may necessitate lower-extremity amputation. Levels of Evidence: Level III: Retrospective cohort study.

Elevated Preoperative Hemoglobin A1c Associated with Increased Wound Complications in Diabetic Patients Undergoing Primary, Open Carpal Tunnel Release

BACKGROUND

An increased rate of complications has been demonstrated with increasing hemoglobin A1c value for a variety of orthopedic procedures, including arthroplasty and spine surgery. The authors investigated the effects of elevated hemoglobin A1c value on postoperative complications at the time of carpal tunnel release.

METHODS

This retrospective, cohort study evaluated all diabetic patients with a preoperative hemoglobin A1c value within 90 days of primary, open carpal tunnel release at a single academic institution within the past 10 years. Binary hemoglobin A1c thresholds were tested for association with outcomes of superficial or deep infection, delayed wound healing, and persistent symptoms using chi-square analysis. Multivariable models with adjustment for baseline and operative factors were then constructed. Odds ratios and 95 percent confidence intervals were displayed.

RESULTS

Hemoglobin A1c value greater than or equal to 7.8 percent was most strongly associated with an increased risk of all-cause wound healing complications (p = 0.049) at an odds ratio of 4.2 (95 percent CI, 1.0 to 17.7) in adjusted analyses. Six patients (4 percent) experienced delayed wound healing and five patients (4 percent) developed a superficial infection. Six patients (4 percent) reported persistent carpal tunnel syndrome symptoms.

CONCLUSIONS

Diabetic patients undergoing open, primary carpal tunnel release with a hemoglobin A1c value of 7.8 percent or higher had a higher rate of postoperative wound complications compared to diabetic patients with improved preoperative glucose control. Diabetics with poor glycemic control should be counseled that their risk of postoperative complication is higher. Further work is needed to determine whether delaying surgery to optimize glucose control could result in a reduction of wound healing complications.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Risk, II.

Outcome of trans-metatarsal amputations in patients with diabetes mellitus

BACKGROUND

This retrospective case series reports the reoperation rate, survival rate and mobility status in patients with diabetes mellitus who had undergone a trans-metatarsal amputation (TMA) managed within a diabetic foot care service.

METHODS

Forty-one consecutive patients (37 men, 4 women) underwent a TMA with primary wound closure between January 2008 and December 2017. Eighty-eight per cent (36/41) of the patients were followed-up for a mean of 2.3 years. The outcomes were retrospectively reviewed.

RESULTS

Four (11%) of the 36 patients required reoperation, including three (8%) major amputations. All of the patients requiring a reoperation had peripheral vascular disease. Eleven patients died giving a four-year survival rate of 69% (25/36). Of the surviving patients who had not required revision to a major amputation 96% (21/22) were fully mobile in bespoke orthoses. A third used a walking cane.

CONCLUSION

This study shows that a TMA with primary wound closure in patients with diabetes mellitus, is effective for limb salvage with low reoperation and major amputation rates. A well healed TMA stump provides independent mobility in the majority of patients. The failures occurred in patients with peripheral vascular disease who, even after percutaneous trans-luminal angioplasty, had a 19% major amputation rate.

LEVEL OF EVIDENCE

Level IV, retrospective case series.

What Is the Treatment "Algorithm" for Infection After Ankle or Hindfoot Arthrodesis?

RECOMMENDATION

There is no universal algorithm for addressing the infected ankle or subtalar arthrodesis. A potential algorithm created by consensus is.

LEVEL OF EVIDENCE

Consensus.

DELEGATE VOTE

Agree: 100%, Disagree: 0%, Abstain: 0% (Unanimous, Strongest Consensus).

Outcomes of Wound Healing and Limb Loss After Transmetatarsal Amputation in the Presence of Peripheral Vascular Disease

Transmetatarsal amputation (TMA) is the procedure of choice in treating forefoot gangrene and infection. Foot and ankle and vascular surgeons work closely together in limb salvage, but little is known about the timing of vascular intervention to achieve a healed amputation site. This study retrospectively looked at 153 patients with peripheral vascular disease who underwent TMA with a minimum of a 3-year follow-up. A total of 102 patients received vascular intervention: 79 endovascular and 23 open bypass. The primary focus of this study was to look at the timing of vascular intervention, incidence of wound healing, and incidence of limb loss. There was an overall 44% rate of limb loss. Patients who underwent open bypass did better than those who underwent endovascular intervention with a lower incidence of limb loss (87% compared with 51%), and quicker time to wound healing. The timing of vascular intervention, performed either before or after TMA, had no association with wound healing or limb loss. Similarly, the time interval between vascular intervention and TMA had no association with wound healing or limb loss. Comorbidities, including end-stage renal disease on hemodialysis, hyperlipidemia, and congestive heart failure, showed a significant association with TMA stump nonhealing and limb loss. Body mass index ≥30, end-stage renal disease on hemodialysis, and hyperlipidemia were all risk factors for limb loss.

Review of Transmetatarsal Amputations in the Management of Peripheral Arterial Disease in an Asian Population

Objective: To evaluate outcomes after transmetatarsal amputation (TMA) in peripheral arterial disease (PAD) limb salvage in an Asian population and identify risk factors associated with TMA failure. Methodology: A retrospective review of 147 patients with PAD, who had undergone TMA between 2008 and 2014, was carried out. Univariate and multivariate analysis were used to identify predictors of TMA failure. Kaplan-Meier survival analysis was used to calculate major amputation and all-cause mortality rates. Results: The mean age was 66 years. 92% were diabetic patients and 78% had preceded angioplasty. 56% of TMAs were healed via secondary intention, 8% required subsequent split-thickness skin graft closure, 24% required further debridement while 37% had wounds, which failed to heal and required below-knee amputations (BKA). Multivariate analysis showed that diabetes is the only independent predictor of TMA failure (odds ratio (OR) 7.11, p=0.064). Patients with TMA failure were at increased risk of developing nosocomial infections (p=0.025) and faced a higher risk of 30-day re-admission rate (p=0.002). Conclusion: The success rate for PAD limb salvage TMA was 63% and diabetes was an independent predictor of TMA failure. Patients with TMA failure were at increased risks of nosocomial infections, and 30-day re-admissions; hence the risks and benefits of TMA for diabetic foot limb salvage must be individualized for each patient.

Outcomes after foot surgery in people with a diabetic foot ulcer and a 12-month follow-up

OBJECTIVE

The aim of this study was to retrospectively measure the outcomes of foot-sparing surgery at one year follow-up for patients with diabetic foot ulcers (DFUs). We assessed wound healing and the need for further surgery in relation to the variables that influence healing.

METHOD

Data were retrospectively collected by reviewing the electronic files of patients attending the Wound Expert Clinic (WEC). Outcomes of surgical debridement, toe, ray and transmetatarsal amputations were assessed.

RESULTS

A total of 129 cases in 121 patients were identified for inclusion. The results demonstrated that complete wound healing was reached in 52% (61/117) of the patients within 12 months. The need for additional surgery or for major amputation was 56% (n=72/129) and 30% (n=39/129) respectively. The need for an additional procedure was particularly high after surgical debridement (75%, 33/44) and transmetatarsal amputation (64%, 7/11). Risk factors for non-healing or for a major amputation were: infection (p=0.01), ischaemia (p=0.01), a history of peripheral arterial occlusive disease (p<0.01) and smoking (p=0.01). Additional findings were that not all patients underwent vascular assessment and in half of the patients there was a delay in undergoing revascularisation.

CONCLUSION

The results of the study reveal some areas for improvement including timely revascularisation and performance of multiple debridement procedures if needed in order to save a limb.

Is It Worth Discriminating Against Patients Who Smoke? A Systematic Literature Review on the Effects of Tobacco Use in Foot and Ankle Surgery

Although numerous studies have linked smoking with lower extremity wound and bone healing complications, a comprehensive study on the effects of smoking in foot and ankle surgery has not yet been reported. The purpose of the present study was to report the results of our systemic literature review, identifying the effects of tobacco use on common foot and ankle procedures. The systematic literature review was performed according to guidelines set by the PRIMSA statement (Preferred Reporting Items for Systematic Review and Meta-Analyses). Smoking, as a single risk factor, was analyzed and used to compare adverse outcomes in the postoperative setting of foot and ankle surgery. We reviewed 528 abstracts that met our initial identification criteria. After an extensive review process, 46 of the articles (8.71%) met the eligibility requirements to be included in the present study. Distal bunionectomy with osteotomy, first metatarsophalangeal joint arthrodesis, Lapidus bunionectomy, toe amputation, transmetatarsal amputation, Syme's amputation, open reduction internal fixation (ORIF) of calcaneal fractures, ankle fracture ORIF, pilon fracture ORIF, subtalar arthrodesis, rearfoot arthrodesis, tibiocalcaneal arthrodesis, ankle arthrodesis, total ankle arthroplasty, and plastic surgery procedures and their respective negative association with smoking was identified and described in our review. Our systematic literature review revealed that procedures involving arthrodesis, fracture ORIF, and plastic surgery were associated with negative outcomes in smokers. Procedures that did not involve osseous unions such as total ankle arthroplasty and amputations did not appear to have negative outcomes associated with smoking.

Outcomes of dysvascular partial foot amputation and how these compare to transtibial amputation: a systematic review for the development of shared decision-making resources

BACKGROUND

Dysvascular partial foot amputation (PFA) is a common sequel to advanced peripheral vascular disease. Helping inform difficult discussions between patients and practitioners about the level of PFA, or the decision to have a transtibial amputation (TTA) as an alternative, requires an understanding of the current research evidence on a wide range of topics including wound healing, reamputation, quality of life, mobility, functional ability, participation, pain and psychosocial outcomes, and mortality. The aim of this review was to describe a comprehensive range of outcomes of dysvascular PFA and compare these between levels of PFA and TTA.

METHODS

The review protocol was registered in PROSPERO (CRD42015029186). A systematic search of the literature was conducted using MEDLINE, EMBASE, psychINFO, AMED, CINAHL, ProQuest Nursing and Allied Health, and Web of Science. These databases were searched using MeSH terms and keywords relating to different amputation levels and outcomes of interest. Peer reviewed studies of original research-irrespective of the study design-were included if published in English between 1 January 2000, and 31 December 2015, and included discrete cohort(s) with dysvascular PFA or PFA and TTA. Outcomes of interest were rate of wound healing and complications, rate of ipsilateral reamputation, quality of life, functional ability, mobility, pain (i.e., residual limb or phantom pain), psychosocial outcomes (i.e., depression, anxiety, body image and self-esteem), participation, and mortality rate. Included studies were independently appraised by two reviewers. The McMaster Critical Review Forms were used to assess methodological quality and identify sources of bias. Data were extracted based on the Cochrane Consumers and Communication Review Group's data extraction template by a primary reviewer and checked for accuracy and clarity by a second reviewer. Findings are reported as narrative summaries given the heterogeneity of the literature, except for mortality and ipsilateral reamputation where data allowed for proportional meta-analyses.

RESULTS

Twenty-nine unique articles were included in the review, acknowledging that some studies reported multiple outcomes. Eighteen studies reported all-cause proportionate mortality. A smaller number of studies reported outcomes related to functional ability (two), mobility (four), quality of life (three), ipsilateral reamputation (six) as well as wound healing and complications (four). No studies related to pain, participation or psychosocial outcomes met the inclusion criteria. Subjects were typically older and male and had diabetes among other comorbidities. More detailed information about the cohorts such as race or sociodemographic factors were reported in an ad hoc manner. Common sources of bias included contamination, co-intervention, or lack of operational definition for some outcomes (e.g., wound healing) as illustrative examples.

CONCLUSIONS

Aside from mortality, there was limited evidence regarding outcomes of dysvascular PFA, particularly how outcomes differ between levels of PFA and TTA. Acknowledging that there is considerable uncertainty given the small body of literature on many topics where the risk of bias is high, the available evidence suggests that a large proportion of people with PFA experience delayed wound healing and ipsilateral reamputation. People with TTA have increased risk of mortality compared to those with PFA, which may reflect that those considered suitable candidates for TTA have more advanced systemic disease that also increases the risk of dying. Mobility and quality of life may be similar in people with PFA and TTA.

SYSTEMATIC REVIEW REGISTRATION

CRD42015029186.

An Approach to Transmetatarsal Amputation to Encourage Immediate Weightbearing in Diabetic Patients

Transmetatarsal amputation remains the standard treatment for the unsalvageable diabetic forefoot; however, this operation is often complicated by wound dehiscence, ulceration, and the need for additional surgery and tendon balancing. The technique described in the present report provides an uncomplicated suturing method for closure of a standard transmetatarsal amputation. A drill hole is created through the first, second, and fourth metatarsals, which facilitates added stability to the plantar flap of the residual metatarsals. The patients are encouraged to begin protected weightbearing as early as the first postoperative day. The security of the flap promotes immediate weightbearing, which could result in fewer postoperative complications of transmetatarsal amputations. Early weightbearing will not only encourage tendon rebalancing, but also could improve angiogenesis through capillary ingrowth.

American College of Foot and Ankle Surgeons® Clinical Consensus Statement: Perioperative Management

A wide range of factors contribute to the complexity of the management plan for an individual patient, and it is the surgeon's responsibility to consider the clinical variables and to guide the patient through the perioperative period. In an effort to address a number of important variables, the American College of Foot and Ankle Surgeons convened a panel of experts to derive a clinical consensus statement to address selected issues associated with the perioperative management of foot and ankle surgical patients.

The care of transmetatarsal amputation in diabetic foot gangrene

Diabetic foot ulcerations may determine minor or major amputation, with a high impact on patients' life expectation and quality of life and on economic burden. Among minor amputations, transmetatarsal amputation (TMA) appears to be the most effective in terms of limb salvage rates and in maintaining foot and ankle biomechanics. In spite of this, TMA needs particular pre- and postoperative management in order to avoid the frequent failure rates. A systematic review was undertaken of studies concerning TMA and its care in diabetic foot gangrene. Studies were identified by searching the MEDLINE, Scopus and Science Direct databases until 13 January 2016. All studies were assessed using the Downs and Black quality checklist. Of the 348 records found, 86 matched our inclusion criteria. After reading the full-text articles, we decided to exclude 35 manuscripts because of the following reasons: (1) no innovative or important content, (2) no multivariable analysis, (3) insufficient data, (4) no clear potential biases or strategies to solve them, (5) no clear endpoints and (6) inconsistent or arbitrary conclusions. The final set included 51 articles. In the current literature, there are less data about TMA, indication for the selection of patients, outcomes and complications. Generally, the judgment of an experienced physician is one of the best indicators of subsequent healing. Ankle brachial indices, toe pressures, laser Doppler skin perfusion pressures, angiography and Doppler assessment of foot vasculature may help physicians in this decision. In any case, despite the presumed lower healing rate, it is reasonable to pursue a TMA in a patient with a higher likelihood of continued ambulation. Furthermore, tailored wound closure, adjuvant local treatments and the choice of the most appropriate antibiotic therapy, when infection occurs, are pivotal elements for the success of TMA procedures. TMA is a valuable option for diabetic foot gangrene that can prevent major limb loss and minimise loss of function, thus improving the quality of life for diabetic patients.

Reoperation and Reamputation After Transmetatarsal Amputation: A Systematic Review and Meta-Analysis

Transmetatarsal amputations have generally been accepted as a relatively more definitive amputation compared with other lesser ray resections. However, many investigators have reported a high occurrence of more proximal amputation after transmetatarsal amputation. A systematic review was performed to evaluate the occurrence of reamputation and reoperation after transmetatarsal amputations. A search of the Medline, CINAHL, and Cochrane Central databases yielded 159 abstracts. After review, 24 reports were included in the study. A total of 391 (26.9%) reoperations were identified after 1453 transmetatarsal amputations. Any level reamputation occurred in 152 (29.7%) of 365 transmetatarsal amputations and major amputation occurred in 380 (33.2%) of 1146 transmetatarsal amputations. Using a random effects model, the reoperation rate was estimated at 24.43% (95% confidence interval 11.64% to 37.21%), the reamputation rate was estimated at 28.37% (95% confidence interval 19.56% to 37.19%), and the major amputation rate was estimated at 30.16% (95% confidence interval 23.86% to 36.47%). These findings raise questions about the conventional wisdom of performing primary transmetatarsal amputation in lieu of other minor amputations, such as partial first ray amputation, and suggest that the choice between transmetatarsal amputation and other minor amputations might be a decision that depends on very patient-specific factors.

Association Between Hemoglobin A1c and Surgical Morbidity in Elective Foot and Ankle Surgery

The current guidelines for the management of diabetes in adults have recommended strict glycemic control, with a target hemoglobin A1c of 7.0%. Increasing evidence has shown that strict glycemic control decreases the risk of developing the organ system complications associated with diabetes. Elevated hemoglobin A1c levels have been theorized as a risk factor for complications after elective foot and ankle surgery. To test this hypothesis, we reviewed the Department of Veterans Affairs national administrative and clinical databases for a 6-year period (January 2008 to December 2013). During this period, 21,854 diabetic patients had a recorded hemoglobin A1c measurement within 1 year before undergoing elective foot and ankle surgery. We then identified those patients who had experienced postoperative complications within 30 days of elective foot or ankle surgery using the International Classification of Diseases, ninth revision, codes. The complications were classified into 4 groups: infection, wound healing, mechanical failure, and cardiovascular/pulmonary. The overall 30-day postoperative complication rate was 3.2%. The most common complication was infection (42.3%), followed by mechanical failure (33.4%), cardiovascular/pulmonary (18.4%), and wound healing (5.8%). The average hemoglobin A1c of a patient who had experienced a complication was 6.29% compared with 6.11% for a patient who had not experienced 1 of the 4 complications (p < .001). Logistic regression analysis revealed that for each 1% increase in hemoglobin A1c, the odds of developing a complication increased by 5%. More significant was the 1.78 times increased risk of developing a complication for patients with neuropathy (95% confidence interval 1.45 to 2.20; p = .0001). Even more notable was the associated risk of complications after elective foot and ankle surgery for those patients with comorbid conditions. Patients demonstrated 3.08 times the risk of developing a complication when the patient had 2 to 3 identified comorbid conditions associated with diabetes mellitus (95% confidence interval 2.42 to 3.92; p = .0001). The present retrospective observational investigation has demonstrated glycemic control influences the postoperative complication rates in elective foot and ankle surgery. However, the data collected from the present study have also demonstrated that the complication rates are multifactorial. Comorbid conditions and the presence of peripheral neuropathy also play a significant role in determining a patient's risk of complications after elective foot and ankle surgery.

Comparison of Hallux Interphalangeal Joint Arthrodesis Fixation Techniques: A Retrospective Multicenter Study

Few studies have investigated the complications that occur after hallux interphalangeal joint arthrodesis. The present study evaluated complications in 152 patients aged 18 to 80 years from 2005 to 2012 from 4 different academic institutions after hallux interphalangeal joint arthrodesis. Overall, 65.8% of the patients had ≥1 complication. Infections occurred in 16.5%, dehiscence in 12.5%, and reoperations in 27.0%. The clinical nonunion rate was ≥17.8%, and the radiographic nonunion rate was ≥13.8%. After logistic regression analysis, only the study site and peripheral neuropathy were associated with having ≥1 complication (p < .01 and p < .05, respectively). Single screw fixation compared with other fixation did not have a statistically significant influence on the postoperative complications. However, when fixation was expanded to 4 categories, single screw fixation had lower infection and reoperation rates than either crossed Kirschner wires or other fixation category but not compared with crossed screws on multivariate logistic regression analysis. Although additional studies are warranted, the findings from the present study might aid in both the prognosis of complications and the support of the use of a single screw over crossed Kirchner wire fixation in hallux interphalangeal joint arthrodesis.

Cigarette smoking increases complication rate in forefoot surgery

BACKGROUND

Cigarette smoking is known to increase perioperative complication rates, but no study to date has examined its effect specifically in forefoot surgery. The purpose of this study was to determine whether cigarette smoking increased complications after forefoot surgery.

METHODS

The records of 602 patients who had forefoot surgery between 2008 and 2010, and for whom smoking status was known, were reviewed. Patients were categorized into 3 groups based on smoking status: active smoker, smoker in the past, or nonsmoker. Medical records were reviewed for occurrence of complications, including nonunion, delayed union, delayed wound healing, infection, and persistent pain.

RESULTS

Active smokers were found to have a notably higher complication rate (36.4%) after forefoot surgery than patients who previously (16.5%) or never (8.5%) smoked. Patients who continued to smoke in the perioperative period had the highest percentage of delayed union (3.0%), infection (9.1%), delayed wound healing (10.6%), and persistent pain (15.2%). Active cigarette smokers were 4.3 times more likely to have a complication than nonsmokers. Patients who smoked at any point in the past but quit prior to surgery were 1.9 times more likely than nonsmokers to incur a complication. The average time of smoking cessation for patients who had smoked at any point in the past but had quit prior to surgery was 17 years. For active smokers, those with a complication smoked an average of 18 cigarettes daily, while those without a complication smoked 14 cigarettes daily.

CONCLUSIONS

Before forefoot surgery, surgeons should educate patients who smoke about their increased risk of complications and encourage smoking cessation.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Management in high-risk patients

Injuries to the foot and ankle are often missed or underestimated in patients with polytrauma and are a source of long-term limitations. Injures below the knee are among the highest causes for unemployment, longer sick leave, more pain, more follow-up appointments, and decreased overall outcome. As mortalities decrease for patients with polytrauma a greater emphasis on timely diagnosis and treatment of foot and ankle injuries is indicated. Geriatric patients represent nearly one-quarter of trauma admissions in the United States. This article discusses perioperative management and complications associated with foot and ankle injuries in polytrauma, and in diabetic and geriatric patients.

The impact of glycosylated hemoglobin and diabetes mellitus on wound-healing complications and infection after foot and ankle surgery

BACKGROUND

The relationship between hyperglycemia and adverse outcomes after surgery has been widely documented. Long-term glucose control has been recognized as a risk factor for postoperative complications. In the foot and ankle literature, long-term glycemic control as a potential perioperative risk factor is not well studied. Our goal was to investigate whether hemoglobin A1c (HbA1c) level was independently associated with postoperative complications in a retrospective cohort study.

METHODS

Three hundred twenty-two patients with a diagnosis of diabetes mellitus were enrolled in the study to assess risk factors associated with postoperative foot and ankle surgery complications.

RESULTS

Bivariate analyses showed that HbA1c level and having at least one comorbidity were associated with postoperative infections. However, after adjusting for other covariates, the only significant factor was HbA1c level, with each increment of 1% increasing the odds of infection by a factor of 1.59 (95% confidence interval [CI], 1.28-1.99). For postoperative wound-healing complications, bivariate analyses showed that body mass index, having at least one comorbidity, and HbA1c level were significant factors. After adjusting for other covariates, the only significant factors for developing postoperative wound complications were having at least one comorbidity (odds ratio, 2.03; 95% CI, 1.22-3.37) and HbA1c level (each 1% increment) (odds ratio, 1.25; 95% CI, 1.02-1.53).

CONCLUSIONS

In this retrospective study, HbA1c level had the strongest association with postoperative foot and ankle surgery complications in patients with diabetes.

Delayed fracture healing and increased callus adiposity in a C57BL/6J murine model of obesity-associated type 2 diabetes mellitus

Introduction

Impaired healing and non-union of skeletal fractures is a major public health problem, with morbidity exacerbated in patients with diabetes mellitus (DM). DM is prevalent worldwide and affects approximately 25.8 million US adults, with >90% having obesity-related type 2 DM (T2DM). While fracture healing in type 1 DM (T1DM) has been studied using animal models, an investigation into delayed healing in an animal model of T2DM has not yet been performed.

Methods

Male C57BL/6J mice at 5 weeks of age were placed on either a control lean diet or an experimental high-fat diet (HFD) for 12 weeks. A mid-diaphyseal open tibia fracture was induced at 17 weeks of age and a spinal needle was used for intra-medullary fixation. Mice were sacrificed at days 7, 10, 14, 21, 28, and 35 for micro-computed tomography (μCT), histology-based histomorphometry and molecular analyses, and biomechanical testing.

Results

HFD-fed mice displayed increased body weight and impaired glucose tolerance, both characteristic of T2DM. Compared to control mice, HFD-fed mice with tibia fractures showed significantly (p<0.001) decreased woven bone at day 28 by histomorphometry and significantly (p<0.01) decreased callus bone volume at day 21 by μCT. Interestingly, fracture calluses contained markedly increased adiposity in HFD-fed mice at days 21, 28, and 35. HFD-fed mice also showed increased PPARγ immunohistochemical staining at day 14. Finally, calluses from HFD-fed mice at day 35 showed significantly (p<0.01) reduced torsional rigidity compared to controls.

Discussion

Our murine model of T2DM demonstrated delayed fracture healing and weakened biomechanical properties, and was distinctly characterized by increased callus adiposity. This suggests altered mesenchymal stem cell fate determination with a shift to the adipocyte lineage at the expense of the osteoblast lineage. The up-regulation of PPARγ in fracture calluses of HFD-fed mice is likely involved in the proposed fate switching.

Neuropathy and poorly controlled diabetes increase the rate of surgical site infection after foot and ankle surgery

BACKGROUND

This prospective study was designed to evaluate the frequency of surgical site infection in patients treated with foot and ankle surgery. Our hypothesis was that patients with complications of diabetes are at increased risk for surgical site infection compared with patients without diabetes and patients with diabetes who do not have diabetic complications. Another goal was to compare the association of neuropathy with surgical site infection in both nondiabetic and diabetic patients.

METHODS

Two thousand and sixty consecutive surgical cases were evaluated. Group 1 included nondiabetic patients without neuropathy, Group 2 included nondiabetic patients with neuropathy, Group 3 included patients with diabetes but no diabetic complications, and Group 4 included patients with diabetes who had at least one complication of diabetes.

RESULTS

The surgical site infection rate in this study was 3.1%. Patients with complicated diabetes had a 7.25-fold increased risk of surgical site infection compared with nondiabetic patients without neuropathy and a 3.72-fold increased risk compared with patients with uncomplicated diabetes. Patients with complicated diabetes had a nonsignificant 1.54-fold higher rate of surgical site infection compared with nondiabetic patients with neuropathy. Nondiabetic patients with neuropathy had a significant 4.72-fold increased risk of surgical site infection compared with nondiabetic patients without neuropathy. Despite this, nondiabetic patients with neuropathy did not have a significantly higher rate of surgical site infection than patients with uncomplicated diabetes, and the frequency of surgical site infection in the group with uncomplicated diabetes was not significantly different from that in the nondiabetic patients without neuropathy. Multivariable logistic regression analysis demonstrated that peripheral neuropathy and a hemoglobin A1c of ≥8% were independently associated with surgical site infection.

CONCLUSIONS

Complicated diabetes increases the risk of surgical site infection after foot and ankle surgery. Patients who had diabetes without complications did not have a greater risk of surgical site infection compared with nondiabetic patients without neuropathy. The presence of neuropathy increases the risk of surgical site infection even in patients without diabetes. Poor long-term glycemic control is also associated with an increased risk of surgical site infection.

LEVEL OF EVIDENCE

Prognostic Level I. See Instructions for Authors for a complete description of levels of evidence.

Diabetes mellitus: musculoskeletal manifestations and perioperative considerations for the orthopaedic surgeon

Diabetes mellitus is a disease of uncontrolled hyperglycemia. Despite a more sophisticated understanding of the pathophysiology of diabetes mellitus and despite pharmacologic advancements that enable better glycemic control, the prevalence of this disease and its devastating sequelae continue to rise. The adverse effects of diabetes on the nervous, vascular, and immune systems render the musculoskeletal system vulnerable to considerable damage. Foot involvement has traditionally been thought of as the most severe and frequently encountered orthopaedic consequence. However, the upper extremity, spine, and muscles are also commonly affected. Orthopaedic surgeons are more involved than ever in the care of patients with diabetes mellitus, and they play a vital role in the multidisciplinary approach used to treat these patients. As a result, surgeons must have a comprehensive understanding of the musculoskeletal manifestations and perioperative considerations of diabetes in order to most effectively care for patients with diabetes mellitus.

Perioperative laboratory assessment of diabetic foot infections undergoing amputation: a systematic review

Diabetes is the leading cause of nontraumatic amputations. Although laboratory assessment may not alone determine the optimal level of amputation thorough assessment of a variety of laboratory values is critical to overall care of the patient and may place the patient into risk category. This systematic review analyzes publications related to diabetic lower extremity amputations and associated laboratory values, including lymphocyte count, albumin, hemoglobin, and glycemic control.

Trends in postoperative infection rates and their relationship to glycosylated hemoglobin levels in diabetic patients undergoing foot and ankle surgery

The association of hyperglycemia with postoperative infectious complications after foot and ankle surgery has been well studied. However, many surgeons in their current practice use the somewhat arbitrary cutoff of 7% glycosylated hemoglobin (HbA1c) as the level above which surgery is considered unsafe and conducive to complications. Our goal in the present study was to assess the relationship between the HbA1c levels and the rate of postoperative infection to begin to determine whether 7% is a suitable cutoff or whether this level needs to be reevaluated. Furthermore, we were interested in the general trends relating to the infection rates and preoperative HbA1c levels. Our preliminary, subjective, analysis has indicated that infection rates increase steadily as the HbA1c increases toward 7.3%, increase rapidly at an HbA1c of 7.3% to 9.8%, and then level off. Additional study is warranted to better understand the role played by other covariates in determining the infection rate and to investigate whether patient selection has influenced the appearance of decreased infection rates at high HbA1c levels. Additional study could also assess similar relationships for other types of complication, such as nonunion, and perhaps examine different foot and ankle procedures in isolation.

Gram-Negative Diabetic Foot Osteomyelitis

Osteomyelitis frequently complicates infections in the feet of patients with diabetes. Gram-positive cocci, especially Staphylococcus aureus, are the most commonly isolated pathogens, but gram-negative bacteria also cause some cases of diabetic foot osteomyelitis (DFO). These gram-negatives require different antibiotic regimens than those commonly directed at gram-positives. There are, however, few data on factors related to their presence and how they influence the clinical picture. We conducted a retrospective study to determine the variables associated with the isolation of gram-negative bacteria from bone samples in cases of DFO and the clinical presentation of these infections. Among 341 cases of DFO, 150 had a gram-negative isolate (alone or combined with a gram-positive isolate) comprising 44.0% of all patients and 50.8% of those with a positive bone culture. Compared with gram-positive infections, wounds with gram-negative organisms more often had a fetid odor, necrotic tissue, signs of soft tissue infection accompanying osteomyelitis, and clinically severe infection. By multivariate analysis, the predictive variables related to an increased likelihood of isolating gram-negatives from bone samples were glycated hemoglobin <7% (odds ratio [OR] = 2.0, 95% confidence interval [CI] = 1.1-3.5) and a wound caused by traumatic injury (OR = 2.0, 95% CI = 1.0-3.9). Overall, patients whose bone samples contained gram-negatives had a statistically significantly higher prevalence of leukocytosis and higher white blood cell counts than those without gram-negatives. In conclusion, gram-negative organisms were isolated in nearly half of our cases of DFO and were associated with more severe infections, higher white blood cell counts, lower glycated hemoglobin levels, and wounds of traumatic etiology.

Factors associated with nonunion, delayed union, and malunion in foot and ankle surgery in diabetic patients

The incidence of bone healing complications in diabetic patients is believed to be high after foot and ankle surgery. Although the association of hyperglycemia with bone healing complications has been well documented, little clinical information is available to show which diabetes-related comorbidities directly affect bone healing. Our goal was to better understand the risk factors associated with poor bone healing in the diabetic population through an exploratory, observational, retrospective, cohort study. To this end, 165 diabetic patients who had undergone arthrodesis, osteotomy, or fracture reduction were enrolled in the study to assess the risk factors associated with nonunion, delayed union, and malunion after elective and nonelective foot and/or ankle surgery. Bivariate analyses showed that a history of foot ulcer, peripheral neuropathy, and surgery duration were statistically significantly associated with bone healing complications. After adjusting for other covariates, only peripheral neuropathy, surgery duration, and hemoglobin A1c levels >7% were significantly associated statistically with bone healing complications. Of the risk factors we considered, peripheral neuropathy had the strongest association with bone healing complications.

Reamputation after minor foot amputation in diabetic patients: risk factors leading to limb loss

The prevalence of lower extremity reamputation in diabetic patients has been well-documented. We sought to determine the risk factors for major lower extremity amputation (LEA) after minor foot amputation in diabetic patients. We studied 163 diabetic patients who had undergone an initial minor foot amputation and then had undergone at least 1 subsequent major or minor LEA. The patients were separated into a minor LEA group (initial minor LEA followed by at least 1 subsequent minor LEA) and a major LEA group (initial minor LEA followed by at least 1 subsequent major LEA). We then studied the possible risk factors for both groups. The possible risk factors analyzed were age, glycemic control, kidney function, previous kidney or kidney-pancreas transplantation, smoking history, and presence and severity of peripheral arterial disease (PAD). No statistical significance was found between the 2 groups for hemoglobin A1c, smoking status, chronic kidney disease, end-stage renal disease requiring dialysis, kidney or kidney-pancreas transplantation, or vascular intervention (peripheral arterial bypass). In the minor group, 22.23% had severe PAD. In the major group, 71.15% had severe PAD. This was statistically significant (p < .001). The average interval to major amputation in those without PAD, mild to moderate PAD, and severe PAD was 1,180.9, 591.0, and 559.6 days, respectively. This demonstrates the importance of assessing the peripheral vascular status in all diabetic patients with minor LEA. Early referral to a vascular surgeon might delay (or prevent) major LEA.

Diabetic calcaneal fractures

Calcaneal fractures among the diabetic population are severe and complex injuries that warrant careful evaluation in an effort to carry out adequate conservative or surgical management. The complication rates associated with diabetic fracture management are increased and may include poor wound healing, deep infection, malunion, and Charcot neuroarthropathy, each of which can pose a risk for limb loss. The significant surgery-associated morbidity accompanying diabetic calcaneal fractures has led to improved methods of calcaneal fracture management. This article reviews the overall management of diabetic calcaneal fractures, complications, and outcomes.

Partial foot amputation in patients with diabetic foot ulcers

BACKGROUND

Transtibial amputations (TTA) are performed for recalcitrant or infected ulcers of the midfoot, hindfoot, or ankle. This procedure results in decreased ambulatory status caused by increased oxygen demands and energy expenditure. Partial foot amputations have the advantage of being an end-bearing limb and require less work to walk, theoretically suggesting improved functional outcome. The purpose of this research was to examine the longevity, outcome, and mortality of partial foot amputations as an alternative to TTA.

METHODS

Retrospective chart review identified diabetic patients with transmetatarsal, Chopart's, and calcanectomy amputations for osteomyelitis or nonhealing ulcers. A control group consisted of diabetic patients who underwent TTA. A comparison between groups examined mortality, proximal ipsilateral reamputation, and a validated ambulatory functional outcome measure.

RESULTS

Eighteen TTA patients were enrolled. The 5-year mortality rate was 0.45, one patient required reamputation, and the mean postoperative ambulatory score was 2.8. Twenty-one transmetatarsal patients were enrolled. The 5-year mortality rate was 0.30, two patients required reamputation, and the mean postoperative ambulatory score was 4.3. Ten Chopart's amputation patients were enrolled. The 5-year mortality rate was 0.36, six patients required reamputation, and the mean postoperative ambulatory score was 4.3. Seventeen partial calcanectomy patients were enrolled. The 5-year mortality rate was 0.69, six patients required reamputation, and the mean postoperative ambulatory score was 4.3. Sixteen total calcanectomy patients were enrolled. The 5-year mortality rate was 0.59, five patients required reamputation, and the mean postoperative ambulatory score was 3.3.

CONCLUSION

TTA is associated with high morbidity and mortality, which suggests that the advantage of partial foot amputations should be investigated. Only transmetatarsal amputations at 1 and 3 years were statistically lower for mortality than TTA. Partial foot amputations at the other levels failed to show statistically improved survivorship. Transmetatarsal and Chopart's amputations had high ambulatory levels and the longest durability, which suggests that these amputations may provide some ambulatory advantage.

Transmetatarsal amputation: a case series and review of the literature

Foot ulceration is a major cause of morbidity amongst patients with diabetes. In severe cases of ulceration, osteomyelitis and amputation can ensue. A distinct lack of agreement exists on the most appropriate level of amputation in cases of severe foot ulceration/infection to provide predictable healing rates. This paper provides an overview of the transmetatarsal amputation (TMA) as a limb salvage procedure and is written with the perspective and experiences of the Department of Podiatric Surgery at West Middlesex University Hospital (WMUH). We have reflected on the cases of 11 patients (12 feet) and have found the TMA to be an effective procedure in the management of cases of severe forefoot ulceration and infection.

Ankle and hindfoot fusions: comparison of outcomes in patients with and without diabetes

BACKGROUND

Patients with diabetes mellitus (DM) are believed to have higher complication rates when undergoing ankle and hindfoot fusions, but data is lacking. The purpose of this study was to compare the postoperative outcomes of major foot and ankle arthrodeses in patients with and without DM. Another goal was to evaluate what effect glycemic control had on the outcomes of patients with diabetes.

METHODS

A retrospective review of charts from operative years 2005 to 2010 was performed. Inclusion criteria encompassed patients requiring major hindfoot and/or ankle fusion. Exclusion criteria included any patient who did not have at least 6-month followup. Seventy four patients with DM were matched with 74 non-DM patients based on age, gender, and length of surgery. Significance was set at p < 0.05 with associated 95% confidence intervals.

RESULTS

The overall complication rate was found to be significantly higher in patients with DM, a history of tobacco use, and peripheral neuropathy. The postoperative infection rate was found to be significantly higher in patients with DM, poor long-term glucose control (Hgb A1c levels greater than or equal to 7%), a history of tobacco use, peripheral artery disease, and peripheral neuropathy. Our rate of noninfectious complications was found to be significantly higher in patients with DM, poor short-term glucose control (a preoperative glucose greater than 200 mg/dL), a history of tobacco use, and previous solid organ transplantation. Patients greater than or equal to 65 years of age were significantly associated with fewer overall complications and postoperative infections.

CONCLUSION

This study confirmed our hypothesis that patients with DM were at increased risk for postoperative complications after foot and/or ankle arthrodesis when compared to patients without DM. A secondary finding of this study demonstrated patients with poor short- and long-term glucose control experienced more complications.

Impact of perioperative glycaemia and glycated haemoglobin on the outcomes of the surgical treatment of diabetic foot osteomyelitis

Perioperative glycaemic control during admission was a predictive factor of amputation in a prospective cohort of 81 patients with diabetes who underwent surgical treatment for osteomyelitis. Glycaemic control before admission, as determined by glycosylated haemoglobin, did not have any influence on the outcomes.

A case history of multimodal therapy in healing a complicated diabetic foot wound: negative pressure, dermal replacement and pulsed radio frequency energy therapies

Advanced multimodal therapies are being used with increasing frequency in the management of difficult or complex wounds. Although the primary goal remains to expedite complete healing, secondary goals include avoidance of superimposed infection, repeated hospitalisations and subsequent amputations. We describe a case involving a limb- and life-threatening necrotising infection in a diabetic patient in which we successfully applied negative pressure wound therapy, dermal replacement therapy and pulsed radio frequency energy to achieve definitive healing. Further study is warranted to elucidate the most effective combinations of such therapies to promote healing of similarly complex wounds.