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

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.

Guillotine Transmetatarsal Amputations With Staged Closure Promote Early Ambulation and Limb Salvage in Patients With Advanced Chronic Limb-Threatening Ischemia

PURPOSE

Transmetatarsal amputation (TMA) with primary closure has long been an option for limb salvage in patients with advanced chronic limb-threatening ischemia (CLTI) with extensive tissue loss of the forefoot. However, TMA healing and closure techniques are challenging, specifically in high-risk patients. Guillotine transmetatarsal amputations (gTMA) with staged closure may provide an alternative treatment in this population. We report long-term outcomes of such technique.

MATERIALS AND METHODS

A single-center retrospective cohort study of CLTI patients undergoing gTMA between 2017 and 2020 was performed. Limb salvage, wound healing, and survival rates were quantified using Kaplan-Meier (KM) analysis. Multivariate regression was used to identify the effect of patient characteristics on the outcomes.

RESULTS

Forty-four gTMA procedures were reviewed. Median follow-up was 381 (interquartile range [IQR], 212-539.75) days. After gTMA, 87.8% (n=36) of the patients were able to ambulate after a median interval of 2 (IQR, 1-3) days. Eventual coverage was achieved in a personalized and staged approach by using a combination of skin substitutes (88.6%, n=39) ± split thickness skin grafts (STSG, 61.4%, n=27). KM estimates for limb salvage, wound healing, and survival were 84.1%, 54.5%, and 88.6% at 1 year and 81.8%, 63.8%, and 84.1% at 2 years. Wound healing was significantly associated with STSG application (p=0.002, OR=16.5, 95% CI 2.87-94.81).

CONCLUSION

gTMA resulted in high limb salvage rates during long-term follow-up in CLTI patients. Adjunctive STSG placement may enhance wound healing at the gTMA site, thus leading to expedited wound closure. Surgeons may consider gTMA as an alternative to reduce limb loss in CLTI patients at high risk of major amputation.

CLINICAL IMPACT

Currently, the clinical presentation of CLTI is becoming more complex to deal with due to the increasing comorbidities as the society becomes older. The data shown in this article means for clinicians that when facing diffused forefoot gangrene and extensive tissue loss, limb preservation could still be considered instead of major amputation. Guillotine transmetatarsal amputations in the setting of an aggressive multidisciplinary group, can be healed by the responsibly utilization of dermal substitutes and skin grafts leading to the preservation of the extremity, allowing mobility, avoiding of sarcopenia, and decreasing frailty. This will equate to maintenance of independent living and preservation of lifespan.

Rehabilitation of patients after diabetic foot amputation

Background: Diabetic foot is a diabetes-related complication that often requires amputation due to ulcer, necrosis, infection, and wound healing problems. Amputation decreases ambulation ability and worsens the patient’s general condition. Thus, active gait training is important after amputation.Current Concepts: The level of amputation depends on the anatomical position, for example, toe amputation and transfemoral amputation. The impairment of ambulatory function is also determined by the position of amputation. Continuous rehabilitation exercise is encouraged for ambulation before surgery. Wound management and pain control are needed for early rehabilitation exercise after surgery. The maturation of the amputation stump is especially important and needed for prosthesis wearing. If the general condition of the patient permits, muscle strengthening exercises, joint range of motion exercises, and ambulation exercises should be started as soon as possible.Discussion and Conclusion: Sufficient understanding of functional decline after amputation is required. The clear goal of ambulation should be set in consideration of the patient’s general condition and ability to walk before surgery. The ultimate goal of amputation is not only to remove necrosis, ulcers, and infected tissues but also to restore ambulatory function. Thus, expertise and significant effort before and after surgery are required.

Free Tissue Transfer after Open Transmetatarsal Amputation in Diabetic Patients

BACKGROUND

 Transmetatarsal amputation (TMA) preserves functional gait while avoiding the need for prosthesis. However, when primary closure is not possible after amputation, higher level amputation is recommended. We hypothesize that reconstruction of the amputation stump using free tissue transfer when closure is not possible can achieve similar benefits as primarily closed TMAs.

METHODS

 Twenty-eight TMAs with free flap reconstruction were retrospectively reviewed in 27 diabetic patients with a median age of 61.5 years from 2004 to 2018. The primary outcome was limb salvage rate, with additional evaluation of flap survival, ambulatory status, time until ambulation, and further amputation rate. In addition, subgroup analysis was performed based on the microanastomosis type.

RESULTS

 Flap survival was 93% (26 of 28 flaps) and limb salvage rate of 93% (25 of 27 limbs) was achieved. One patient underwent a second free flap reconstruction. In the two failed cases, higher level amputation was required. Thirteen flaps had partial loss or other complications which were salvaged with secondary intension or skin grafts. Median time until ambulation was 14 days following reconstruction (range: 9-20 days). Patients were followed-up for a median of 344 days (range: 142-594 days). Also, 88% of patients reported good ambulatory function, with a median ambulation score of 4 out of 5 at follow-up. There was no significant difference between the subgroups based on the microanastomosis type.

CONCLUSION

 TMA with free flap reconstruction is an effective method for diabetic limb salvage, yielding good functional outcomes and healing results.

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.