Modified masquelet technique coupled with vascularized fibular transplantation (transposition) in the reconstruction of ultra-long structural bone defects following osteomyelitis debridement: clinical application and preliminary study on therapeutic outcomes.

[BACKGROUND AND OBJECTIVE] Chronic osteomyelitis of long diaphyseal bones often results in extensive structural bone defects following debridement. Traditional approaches such as cancellous bone grafting, fibular transplantation, the classical Masquelet technique, and the Ilizarov method each have inherent limitations when used alone, particularly for defects exceeding 10 cm. This study aimed to evaluate a modified Masquelet technique, in which the induced membrane cavity is reconstructed using vascularized fibular grafts, for the management of ultra-long segmental bone defects.

[METHODS] Between January 2018 and November 2021, five patients (mean age, 50.2 years) with chronic osteomyelitis and diaphyseal bone defects (14-22 cm) were treated using a two-stage surgical protocol. Stage one involved radical debridement and antibiotic-loaded cement implantation. Stage two employed either free vascularized fibular grafts (n = 3) or ipsilateral pedicled fibular transposition (n = 2), combined with autologous iliac cancellous bone grafting. Fixation was achieved using plates (n = 4) or external fixation (n = 1). Patients underwent monthly radiographic follow-up for 9 months and functional evaluation at 12 months. This study was approved by the Ethics Committee of Tongde Hospital of Zhejiang Province (Approval No. ZTD Ethics 2024 Research No. 020-JY).

[RESULTS] All soft tissue defects were closed without tension, and flap donor sites achieved grade A healing. Patients were followed for an average of 23.4 months (range, 16-40 months). Bony union at both ends of the fibular flap was achieved in all cases, with a mean healing time of 3.8 ± 1.3 months. Complete cortical bone formation occurred in four patients within 7-8 months; one femoral case exhibited delayed integration at 18 months. No infections, graft failure, or donor-site complications were observed. Joint function in both adjacent and donor limbs was preserved or improved in all but one patient who had preexisting hip and knee stiffness. All patients regained independent ambulation.

[CONCLUSION] The modified Masquelet technique combined with vascularized fibular grafting is effective for reconstructing ultra-long bone defects following debridement for chronic osteomyelitis, providing robust osteogenesis and favorable functional outcomes.

[CLINICAL RELEVANCE] This combined approach reduces dependence on large-volume cancellous bone grafts and may be particularly suitable for complex cases requiring both infection control and structural reconstruction. Proficiency in microsurgical techniques is critical for successful outcomes.