Amputation versus Free Flap: Long-Term Outcomes of Microsurgical Limb Salvage and Risk Factors for Amputation in the Diabetic Population

Extreme Limb Salvage: The Thin SCIP Flap for Distal Amputation Coverage in Highly Comorbid Patients

BACKGROUND

Limb length preservation is correlated with overall survival. Successful free flap coverage of forefoot, midfoot, and hindfoot amputations can prevent more proximal below-knee amputations but is challenging in patients with multiple comorbidities. The thin superficial circumflex iliac artery perforator (SCIP) flap is well-suited for these patients, as it provides thin, pliable tissue from a favorable donor site.

METHODS

A retrospective review of all patients with distal amputations requiring coverage with a thin SCIP flap between 2016 to 2022 was performed. Patient demographics, amputation levels, and wound characteristics in addition to flap and microsurgery details were analyzed. The primary outcome was limb salvage. Secondary outcomes included partial flap necrosis, flap revision rate, and additional postoperative complications.

RESULTS

Thirty-two patients (mean age, 57.3 years) underwent reconstruction of forefoot, midfoot, and hindfoot amputations with thin SCIP flaps (mean follow-up, 36 months). Twenty-eight patients (87.5%) had diabetes, 27 (84.4%) had peripheral artery disease, and 15 (46.9%) were dialysis-dependent. Average flap size was 59.5 cm 2 and average flap thickness was 5.7 mm. Successful limb salvage was achieved in 27 patients (84.3%). Three cases (9.4%) had total flap loss. Twenty-one flaps (65.6%) had partial necrosis, of which 12 (57.1%) healed with conservative management and 7 (33.3 %) healed after late revision.

CONCLUSIONS

The thin SCIP flap is a useful option for coverage of distal pedal amputations in patients with significant comorbidities. Despite higher rates of partial flap necrosis, free flap reconstruction allowed for high rates of limb salvage in a challenging patient population.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.

Diabetic Foot Osteomyelitis Undergoing Amputation: Epidemiology and Prognostic Factors for Treatment Failure

Background

When treating diabetic foot osteomyelitis (DFO), it remains difficult to determine the presence of residual infection and the optimal treatment after bone resection. In this study, we aimed to investigate the clinical characteristics of and prognostic factors in patients with DFO undergoing amputation.

Methods

This retrospective study involved 101 patients with DFO who underwent amputation. Data on their demographics, clinical characteristics, tissue culture, and surgery type were collected. Patients were grouped according to primary closure status and clinical outcome postamputation. A good outcome was defined as a successful complete remission, characterized by the maintenance of complete wound healing with no sign of infection at 6 months postamputation. Multivariate logistic regression analysis was performed. Outcomes according to surgery type were also analyzed.

Results

Staphylococcus aureus (17%) and Pseudomonas species (14%) were the most prevalent pathogens. Gram-negative bacteria were isolated from 62% of patients. In patients with primary closure, hemodialysis and ankle brachial index (ABI) <0.6 were associated with poor outcomes. In patients with DFO, ABI <0.6 was the only prognostic factor associated with treatment failure. Antimicrobial stewardship allows patients who underwent major amputation to reduce the duration of antibiotic therapy compared to those after minor amputation, although it did not contribute to reducing mortality.

Conclusions

Peripheral artery disease and hemodialysis were associated with poor outcomes despite radical resection of the infected bone. Vigilant monitoring after amputation and antimicrobial stewardship implemented based on microbiological epidemiology, prognostic factors, and the type of surgery are important. A multidisciplinary team could assist in these activities to ensure treatment success.

Does Side Matter? The Impact of Free Flap Harvest Laterality on Ambulatory Function in Lower Extremity Traumatic Reconstruction

BACKGROUND

 Free flaps are essential for limb salvage in patients with lower extremity (LE) trauma; however, significant donor-site morbidity could impact functional outcomes. This study compares postoperative ambulatory function between contralateral and ipsilateral free flap harvest in LE traumatic reconstruction.

METHODS

 A retrospective review was performed on patients who underwent LE reconstruction at a level 1 trauma center from 2009 to 2022. Flap characteristics, injury history, and ambulatory function were collected. Flap harvest laterality was determined in relation to the injured leg. The flaps were categorized as either fasciocutaneous or those that included a muscle component (muscle/myocutaneous). Chi-squared and Mann-Whitney tests were used for statistical analysis.

RESULTS

 Upon review, 173 LE free flaps were performed, of which 70 (65.4%) were harvested from the ipsilateral leg and 37 (34.6%) were from the contralateral leg. Among all LE free flaps, the limb salvage rate was 97.2%, and the flap survival rate was 94.4%. Full ambulation was achieved in 37 (52.9%) patients in the ipsilateral cohort and 18 (48.6%) in the contralateral cohort (p = 0.679). The average time to full ambulation did not vary between these cohorts (p = 0.071). However, upon subanalysis of the 61 muscle/myocutaneous flaps, the ipsilateral cohort had prolonged time to full ambulation (6.4 months, interquartile range [IQR]: 4.8-13.5) compared with the contralateral one (2.3 months, IQR: 2.3 [1.0-3.9]) p = 0.007. There was no significant difference in time to full ambulation between flap harvest laterality cohorts among the fasciocutaneous flaps (p = 0.733).

CONCLUSION

 Among free flaps harvested from the ipsilateral leg, fasciocutaneous flaps were associated with faster recovery to full ambulation relative to muscle/myocutaneous flaps. Since harvesting muscle or myocutaneous flaps from the ipsilateral leg may be associated with a slower recovery of ambulation, surgeons may consider harvesting from a donor site on the contralateral leg if reconstruction requires a muscle component.

Combining antibiotic-loaded bone cement-based free vastus lateralis muscle-sparing flap with split-thickness skin grafts: A reliable strategy for reconstructing diabetic foot ulcers at non-weight-bearing areas

Diabetic foot ulcers (DFUs) present significant challenges due to their associated amputation rates, mortality, treatment complexity and excessive costs. Our earlier work introduced a wound surgical integrated treatment (WSIT) for DFUs, yielding promising outcomes. This study focuses on a specific WSIT protocol employing antibiotic-loaded bone cement (ALBC) in the first Stage, and free vastus lateralis muscle-sparing (VLMS) flaps and split-thickness skin grafts (STSGs) in the second stage to repair non-weight-bearing DFUs. From July 2021 to July 2023, seven DFU patients (aged 47-71 years) underwent this treatment. Demographic data, hospital stay and repair surgery times were collected. Histological and immunohistochemical analyses assessed angiogenesis, collagen deposition and inflammation. SF-36 questionnaire measured pre- and postoperative quality of life. Preoperative ultrasound Doppler showed that the peak blood flow velocity of the recipient area artery was significantly >30 cm/s (38.6 ± 6.8 cm/s) in all patients. Muscle flap sizes varied from 8 × 3.5 × 1 to 18 × 6 × 2 cm. The operation time of the repair surgery was 156.9 ± 15.08 minutes, and the hospital stay was 18.9 ± 3.3 days. Histological analysis proved that covering DFUs with ALBC induced membrane formation and increased collagen, neovascularization and M2 macrophages fraction while reducing M1 macrophages one. All grafts survived without amputation during a 7- to 24-month follow-up, during which SF-36 scores significantly improved. A combination of ALBC with free VLMS flaps and STSGs proved to be safe and effective for reconstructing non-weight-bearing DFUs. It rapidly controlled infection, enhanced life quality and foot function, and reduced hospitalization time. We advocate integrating this strategy into DFU treatment plans.

Does Frailty Predict Outcomes in Patients Undergoing Free or Pedicled Flap Procedures for Lower Extremity Limb Salvage? An Analysis of the American College of Surgeons National Surgical Quality Improvement Program Database

BACKGROUND

 Older and frailer patients are increasingly undergoing free or pedicled tissue transfer for lower extremity (LE) limb salvage. This novel study examines the impact of frailty on postoperative outcomes in LE limb salvage patients undergoing free or pedicled tissue transfer.

METHODS

 The American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database (2010-2020) was queried for free and pedicled tissue transfer to the LE based on Current Procedural Terminology and the International Classification of Diseases9/10 codes. Demographic and clinical variables were extracted. The five-factor modified frailty index (mFI-5) was calculated using functional status, diabetes, chronic obstructive pulmonary disease, congestive heart failure, and hypertension. Patients were stratified by mFI-5 score: no frailty (0), intermediate frailty (1), and high frailty (2 + ). Univariate analysis and multivariate logistic regression were performed.

RESULTS

 In total, 5,196 patients underwent free or pedicled tissue transfer for LE limb salvage. A majority were intermediate (n = 1,977) or high (n = 1,466) frailty. High frailty patients had greater rates of comorbidities-including those not in the mFI-5 score. Higher frailty was associated with more systemic and all-cause complications. On multivariate analysis, the mFI-5 score remained the best predictor of all-cause complications-with high frailty associated with 1.74 increased adjusted odds when compared with no frailty (95% confidence interval: 1.47-2.05).

CONCLUSION

 While flap type, age, and diagnosis were independent predictors of outcomes in LE flap reconstruction, frailty (mFI-5) was the strongest predictor on adjusted analysis. This study validates the mFI-5 score for preoperative risk assessment for flap procedures in LE limb salvage. These results highlight the likely importance of prehabilitation and medical optimization prior to limb salvage.

Ambulatory Status before Diabetic Foot Ulcer Development as a Predictor of Amputation and 1-Year Outcomes: A Retrospective Analysis

Background

Up to 25% of people with diabetes develop a diabetic foot ulcer (DFU) during their lifetime, which precedes approximately 85% of nontraumatic lower limb amputations. Diabetic limb salvage has been at the forefront of recent research, as major amputation is associated with 5-year mortality rates of 52%-80%. We sought to determine if ambulatory status before DFU diagnosis is predictive of amputations and outcomes within 1 year, as no studies have directly examined this relationship.

Methods

A retrospective review of patients diagnosed with DFUs from January 2011 to December 2021 was performed. Patients aged 18 years or more with type II diabetes were included. Ambulatory status was defined as the primary form of mobility reported by the patient before development of DFU, and was categorized as independent ambulation, ambulatory with assisting device (AWAD), or nonambulatory (NA). Statistical analyses included χ2, multinomial, and multivariable logistic regressions.

Results

After review, 506 patients were included. NA (OR = 5.10; P = 0.002) and AWAD status (OR = 2.77; P = 0.01) before DFU development were predictive of major (below or above-knee) amputation during hospitalization, emergency department visits within 30-days (NA: OR = 4.19; P = 0.01, AWAD: OR = 3.09; P = 0.02), and mortality within one-year (NA: OR = 4.19; P = 0.01, AWAD: OR = 3.09; P = 0.02). AWAD status was also associated with increased risk of hospital readmission (OR = 2.89; P < 0.001) within 30-days and any amputation (OR = 1.73; P = 0.01) within 1 year.

Conclusions

In patients with DFUs, NA and AWAD status were predictive of major amputation during hospitalization and are associated with poorer 1-year outcomes, including mortality. Ambulatory status assessment may be used to inform DFU treatment approaches.

Extracorporeal Pedicles for Free Flap Reconstruction in Diabetic Lower Extremity Wounds

Diabetic foot ulcers are a severe complication of diabetes, and their management requires a multidisciplinary approach for optimal management. When treating these ulcers, limb salvage remains the ultimate goal. In this article, we present the “hanging” free flap for the reconstruction of chronic lower extremity diabetic ulcers. This two-staged approach involves standard free flap harvest and inset; however, following inset the “hanging” pedicle is covered within a skin graft instead of making extraneous incisions within the undisturbed soft tissues or tunnels that can compress the vessels. After incorporation, a second-stage surgery is performed in 4 to 6 weeks which entails pedicle division, flap inset revision, and end-to-end reconstruction of the recipient vessel. Besides decreasing the number of incisions on diabetic patients, our novel technique utilizing the “hanging” pedicle simplifies flap monitoring and inset and allows reconstruction of recipient vessels to reestablish distal blood flow.

[Clinical application of microdissected thin thoracodorsal artery perforator flaps for repair of diabetic foot ulcers]

Objective

To explore the effectiveness of microdissected thin thoracodorsal arterial perforator flap (TDAP) in repairing diabetic foot ulcers (DFUs).

Methods

The clinical data of 11 patients with DFUs admitted between March 2020 and February 2021 were retrospectively analyzed, including 5 males and 6 females, aged from 22 to 67 years, with an average of 49.3 years. There were 10 cases of type 2 diabetes and 1 case of type 1 diabetes; the duration of diabetes ranged from 3 months to 25 years (median, 8 months). The duration of DFUs ranged from 6 days to 120 months (median, 1 month). There were 6 cases of grade 3 and 5 cases of grade 4 according to Wagner classification. The tissue necrosis and purulent secretions were found in all ulcer wounds, as well as different degrees of tendon and bone exposure; skin defects ranged from 5 cm×3 cm to 17 cm×6 cm. The DFUs were repaired by microdissected thin TDAP, including 6 cases of flaps (including 1 case of lobulated flap), ranging from 10.0 cm×4.5 cm to 26.0 cm×7.0 cm; 5 cases of chimeric perforator flaps, the range of the flap was 10.0 cm×4.5 cm to 16.0 cm×5.5 cm, and the range of the muscle flap was 6 cm×2 cm to 10 cm×3 cm. The donor site was sutured directly.

Results

The operation time ranged from 3.42 to 11.17 hours, with an average of 5.92 hours. All 11 flaps survived and no vascular crisis occurred; 1 patient had a sinus at the edge of the flap, and the surgical area healed well after dressing change. All 11 patients were followed up 6-12 months, with an average of 9 months. The flap texture was good, the recipient site was in good shape, and there was no swelling; the foot contour was good, the shoes were comfortable to wear, and the movement was good. The incision at the donor site healed by first intention, leaving only linear and concealed scar, without obvious depression deformity, and the shoulder joint function was good.

Conclusion

On the premise of ensuring sufficient blood supply to the lower extremities and strengthening perioperative management, the microdissected thin TDAP to repair DFUs wounds can achieve better effectiveness and appearance; however, the prolonged operation time increases the probability of anesthesia and surgical risks in patients with DFUs.

Limb Salvage in Severe Diabetic Foot Infection

Severe diabetic foot infections (DFI) are both limb threatening and life threatening and associated with negative impact on health-related quality of life. Most severe DFIs require surgical intervention, and the goal of treatment should be preservation of limb function in addition to eradication of infection. Minor amputations are required in approximately 40% and major amputations in approximately 20% of patients. Significant risk factors for lower extremity amputation included male gender, smoking, previous amputation, osteomyelitis, peripheral artery disease, retinopathy, severe infections, gangrene, neuroischemic diabetic foot infections, leukocytosis, positive wound cultures, and isolation of gram-negative bacteria.

Short-term and long-term outcomes of free flap reconstruction versus amputation for diabetic foot reconstruction in patients with end-stage renal disease

BACKGROUND

In Taiwan, the prevalence of diabetes mellitus complicated by end-stage renal disease (ESRD) has been increasing and diabetes-related foot amputation is commonplace. In recent years, limb salvage has become top priority. The long-term outcomes of patients on hemodialysis undergoing diabetic foot reconstruction using free flaps remain unknown.

METHODS

Data from the National Health Insurance Research Database on hemodialysis patients with type 2 diabetes who received amputation or free flap reconstruction surgery for diabetic foot ulcer were analyzed from 2000 to 2013 using International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes. After 1:4 propensity score matching, 86 and 344 patients were assigned to the free flap reconstruction and amputation groups, respectively.

RESULTS

The 5-year survival rate was significantly higher in patients who received free flap compared to the amputated group (1-year survival rate = 80.0% vs. 67.6%, p = 0.030; 3-year survival rate = 49.7% vs. 35.5%, p = 0.024; 5-year rate=30.1% vs. 19.9%, p = 0.018; however, after 5 years, the overall long-term survival rate was similar in both groups (p = 0.064). Patients who had lower limb amputation after flap reconstruction were susceptible to mortality (adjusted HR = 1.39; p = 0.069). Peripheral arterial disease was a dependent risk factor (HR = 1.45; p = 0.037) for long-term survival, whereas old age (> 75 years; HR = 1.65; p = 0.004), cerebrovascular disease (adjusted HR = 1.36; p = 0.011), and sepsis (adjusted HR = 1.85; p = 0.035) served as independent risk factors. Hemodialysis patients with diabetic foot ulcer who had limb salvaged showed a higher 5-year survival rate as compared to the amputated group.

Effect of Electrical Stimulation on Diabetic Human Skin Fibroblast Growth and the Secretion of Cytokines and Growth Factors Involved in Wound Healing

Simple Summary

With the number of diabetic patients on the rise, diabetes has become a major health issue affecting millions of people worldwide. One complication of diabetes is foot ulcers, which are difficult to repair and are thus associated with major clinical problems that may lead to foot amputation and even patient death. The delayed repair of diabetic foot ulcers is due to the slow growth of one of the cell types involved in wound healing, namely, fibroblasts. Fibroblasts inhabit deep skin tissue. Post-wound, they grow and produce skin tissues to enable other cells to close the wound. Even though normal fibroblast growth can be increased by electrical stimulation, it is not clear whether diabetic fibroblast also responds to electrical stimulation. We demonstrated for the first time that a weak direct current electrical field increased diabetic fibroblast growth. The use of electrical stimulation could thus potentially help heal diabetic foot ulcers and ultimately improve patient health and well-being.

Abstract

Diabetic foot ulcers are indicative of an impaired wound healing process. This delay may be resolved through electrical stimulation (ES). The goal of the present study was to evaluate the effect of ES on diabetic fibroblast adhesion and growth, and the secretion of cytokines and growth factors. Diabetic human skin fibroblasts (DHSF) were exposed to various intensities of direct current ES (100, 80, 40 and 20 mV/mm). The effect of ES on fibroblast adhesion and growth was evaluated using Hoechst staining, MTT and trypan blue exclusion assays. The secretion of cytokine and growth factor was assessed by cytokine array and ELISA assay. The long-term effects of ES on DHSF shape and growth were determined by optical microscopy and cell count. We demonstrated that ES at 20 and 40 mV/mm promoted cell adhesion, viability and growth. ES also decreased the secretion of pro-inflammatory cytokines IL-6 and IL-8 yet promoted growth factor FGF7 secretion during 48 h post-ES. Finally, the beneficial effect of ES on fibroblast growth was maintained up to 5 days post-ES. Overall results suggest the possible use of low-intensity direct current ES to promote wound healing in diabetic patients.