Double-barrel fibular graft for metaphyseal areas reconstruction around the knee

Abstract

The metaphyses around the knee (distal femoral and proximal tibial) are junction areas subject to considerable stress. Double-barrel free vascular fibular graft (D-FVFG) provides good bone augmentation and restores the metaphyseal cone; the present study assessed its capacity to restore metaphyseal anatomy and axis and investigated its impact on the neighboring knee joint. Eight D-FVFGs performed for metaphyseal segmental bone defect were followed up for a mean 6.5 years (range, 3-14 years). There were seven femoral nonunions, five of which were septic, and one chondrosarcoma of the tibia. Osteosynthesis used an external fixator (EF) in six cases (four of which bridged the knee), a double plate on the tibia in one case, and intramedullary nailing of the femur in two cases, including one to replace an EF. Adjuvant bone graft was associated in six cases. A protective leg brace was maintained for a mean 16.0±4.0 months. Three arthrolyses were required after final union. Union was achieved in all cases, after a mean 6.4±2.1 months. Sixty-four percent of defect volume was reconstructed. The immediate postoperative mechanical femorotibial angle was 180.3±6.0° and 174.5±5.7° at FU. Mean knee flexion was 96.9±36.0° and extension -5.0±10.0°. Three patients showed symptomatic arthritis at follow-up. D-FVFG satisfactorily restored the anatomy of the metaphyseal area. EF knee bridging seemed to impair varus correction, on top of the systematic problem of stiffness. When possible, internal fixation in first intention or as EF replacement appears to be preferable. Arthritic deterioration of the knee is worsened by initial joint lesions and femorotibial varus. Level IV. retrospective.