Title: Patient-Centric Limb Salvage Using “Spare Parts” Anterior Compartment Flap: A New Frontier in Microsurgical Reconstruction
In a remarkable evolution of microsurgical innovation, a recent case series published in Microsurgery (2025) showcases the use of the “spare parts” en bloc anterior compartment myocutaneous free flap as a groundbreaking reconstructive strategy for patients undergoing simultaneous lower extremity amputations at different levels. The study—authored by Jagasia, Shah, Bagdady, Dumanian, and Fracol—illustrates two unique cases where this technique successfully preserved limb length and optimized postoperative ambulation, setting a precedent for patient-centric surgical innovation in limb salvage.
At the core of this study lies the anatomical and functional ingenuity of harvesting anterior compartment muscles as a myocutaneous free flap from a limb undergoing below-knee amputation (BKA) to reconstruct the contralateral foot undergoing transmetatarsal amputation (TMA). This approach not only redefines the utility of tissues traditionally discarded but significantly elevates the prospects of independent ambulation and prosthetic integration for patients with devastating bilateral limb necrosis.
Clinical Problem and Surgical Dilemma
In severe cases of septic shock or vascular compromise, patients may present with bilateral lower limb necrosis necessitating amputation at two different levels. While BKAs are often unavoidable, preserving as much foot length as possible through a TMA improves gait mechanics and prosthetic compatibility. However, TMA sites frequently suffer from inadequate soft tissue coverage, risking wound complications and functional setbacks.
Traditionally, such defects would necessitate additional donor site morbidity or compromise on amputation level, reducing functional potential. The presented “spare parts” strategy changes this calculus.
Case Narratives: Functional Restoration with Innovation
Case 1
A 48-year-old woman developed necrosis secondary to septic shock, requiring left-sided BKA and right-sided TMA. The surgical team innovatively utilized the anterior compartment of the amputated limb—including the tibialis anterior, extensor digitorum longus, and overlying skin—based on the anterior tibial artery to reconstruct the right foot.
The flap was inset to cover exposed metatarsals with robust vascular anastomoses and nerve coaptation, ensuring protective sensation. Skin grafting supplemented dorsal coverage. At 4-year follow-up, the patient had no complications and could ambulate independently using a prosthesis on the BKA side.
Case 2
A 55-year-old female with a history of multiple cardiac surgeries developed bilateral gangrene from vasopressor-induced ischemia. She underwent right-sided BKA and left-sided TMA. Once again, the anterior compartment muscles and skin were harvested as a single flap to cover the TMA defect.
Despite requiring two minor debulking procedures for volume reduction, the flap healed without complications, and the patient resumed ambulation at one-year follow-up.
Why This Technique Matters: Functional, Ethical, and Surgical Merits
- Preserving Limb Length Without Donor Site Morbidity: Traditionally, flaps for such reconstruction would involve creating new wounds or harvesting from distant sites, often leading to added morbidity. This technique elegantly recycles tissues from an unsalvageable limb.
- Enhanced Prosthetic Compatibility and Gait Mechanics: TMA-level preservation, supported by durable and sensate soft tissue, is more compatible with orthotics and improves balance and propulsion during ambulation.
- Patient-Centered Innovation: This technique puts patient function and long-term independence at the forefront. It exemplifies a philosophy of doing “the most with the least” harm—recycling viable tissues rather than sacrificing additional body parts.
- Surgical Collaboration: Success depended on coordination between orthopedic, vascular, and plastic surgeons, highlighting the need for multidisciplinary collaboration in complex limb salvage.
Technical and Anatomic Insights
The flap design incorporated the entirety of the anterior compartment with vascular pedicles based on the anterior tibial artery. Cadaveric dissections supported intraoperative observations by mapping dominant perforators, primarily situated 13–20 cm below the tibial plateau, and arising through the extensor digitorum longus and lateral septum.
Notably, the second case required volume reduction due to excessive bulk, sparking consideration for perforator-based refinement in future applications—perhaps converting to a fasciocutaneous model.
Limitations and Future Scope
While promising, this technique may not be feasible in all patients, especially those with compromised anterior tibial flow due to atherosclerosis or diabetes. It also demands high-level microsurgical expertise and institutional support, potentially limiting adoption in lower-resource settings.
Nonetheless, the authors argue for its judicious use in select cases, particularly vasopressor-induced necrosis, where anterior compartment perfusion remains intact.
Conclusion
The “spare parts” anterior compartment myocutaneous free flap is a testament to creative, patient-focused microsurgical practice. It expands the reconstructive arsenal for limb salvage, particularly in dual-limb amputation scenarios where traditional techniques fall short. As surgical teams grow increasingly multidisciplinary and microsurgical skill sets mature, such innovations will likely shape the future of limb reconstruction.
Key Points Highlighted:
- Anterior compartment myocutaneous flap from BKA stump used to reconstruct contralateral TMA site.
- Enables limb-length preservation and better prosthetic outcomes.
- Minimizes donor site morbidity by using tissues otherwise discarded.
- Requires precise planning, vascular evaluation, and multidisciplinary collaboration.
- A potential game-changer for selective bilateral amputation scenarios due to septic or vasopressor-induced necrosis.
References
Jagasia, P., Shah, S.A., Bagdady, K., Dumanian, G.A., & Fracol, M.E. (2025). The Use of “Spare Parts” En Bloc Anterior Compartment Myocutaneous Free Flap to Reconstruct the Transmetatarsal Amputation Stump After Contralateral Below Knee Amputation: Report of Two Cases. Microsurgery, 45, e70054. https://doi.org/10.1002/micr.70054
FAQs: Spare Parts Anterior Compartment Flap for Transmetatarsal Amputation Reconstruction
- What is a “spare parts” anterior compartment flap in lower limb reconstruction surgery?
A “spare parts” anterior compartment flap refers to the use of viable muscle, skin, and vessels from a non-salvageable amputated limb to reconstruct another part of the body—typically used to preserve foot length after transmetatarsal amputation. - Can I walk again after transmetatarsal amputation using the anterior compartment flap?
Yes, many patients regain independent ambulation after receiving this flap, especially when the residual foot is reconstructed properly with durable tissue coverage and prosthetic support. - How is this microsurgical flap different from a skin graft in foot amputation cases?
Unlike simple skin grafts, this technique provides both vascularized muscle and skin, ensuring robust healing, reduced infection risk, and better pressure-bearing capabilities in weight-bearing areas. - Is this surgery right for me if I have diabetes or poor blood circulation?
Patients with diabetes or peripheral artery disease may not be ideal candidates if vascular supply to the donor area is compromised. A vascular evaluation is essential before planning. - Will I lose more muscle function if part of my leg is used to reconstruct my foot?
In this technique, the flap is harvested from an amputated limb—meaning the tissue would otherwise be discarded—so there is no additional functional loss from the procedure. - What are the long-term benefits of preserving limb length with this technique?
Preserving more of the foot using this method improves gait, reduces energy expenditure during walking, and enhances prosthetic compatibility—leading to a better quality of life. - Is nerve repair part of the “spare parts” anterior compartment flap reconstruction?
Yes, nerve coaptation is often performed to restore protective sensation to the reconstructed site, reducing the risk of ulcers and injury over time. - How long is the recovery after this type of reconstructive surgery?
Initial recovery may take 2–3 weeks, with most patients resuming prosthetic training and walking within a few months, depending on healing and rehabilitation progress. - Will I need more surgeries after this flap reconstruction?
Some patients may need minor revisions or flap debulking for shoe fitting, but major surgeries are rare when the flap heals well and vascularity is intact. - Where can I find hospitals or surgeons offering this advanced limb salvage microsurgery?
Look for microsurgical centers or plastic surgery units in tertiary hospitals with expertise in limb salvage and lower limb trauma. Multidisciplinary teams are essential for success.
Keywords :
spare parts en bloc anterior compartment myocutaneous free flap, microsurgical reconstruction, lower extremity amputations, prosthetic integration, limb salvage