Introduction and Aims: Rotationplasty is a functional alternative to above knee amputation in very young patients with a lot of growth remaining and patients with large tumors necessitating excision of the thigh musculature. The development of gait following rotationplasty surgery was studied with serial gait and clinical analysis.

Method: Five patients have been reviewed using three dimensional gait analysis incorporating temporal and spatial measures. A gait analysis was performed after the initial prosthetic fitting, six and 12 months postoperatively. The gait analysis included velocity, temporal/spatial measurements (velocity, cadence, step/stride length, pedobarographs), optical tracking and electromyography.

Results: The kinematic and kinetic data revealed the rapid incorporation of knee flexion/extension (ankle dorsi/plantar flexion) into the gait cycle. Electromyography also showed the gastrocnemius to be simulating the quadriceps and the tibialis anterior to mimic the hamstrings in terms of firing time in the stance and swing phase of the rotated limb. Propulsive forces on the kinetic analysis suggest further gait maturation can occur for several years following this procedure.

Conclusion: Children adapt very well to the altered anatomy following rotationplasty and using gait analysis confirms the new role of the altered muscles. Weakness about the hip remains a major concern that needs to be addressed with physiotherapy for several years postoperatively.

Introduction: The majority of patients with extremity osteo-sarcoma undergo limb salvage surgery. The most common location is about the knee, where at least one half of the knee joint is usually removed. A select group of patients with proximal tibial osteosarcomas had preservation of the entire articular surface following reconstruction.

Method: Since 1993, 67 patients with osteosarcoma have been treated. Sixteen patients had tibial tumors. The original MRI of five patients showed part of the condyle appeared uninvolved. These five underwent joint sparing surgery. A portion of the proximal tibial condyle was resected, leaving the articular surface intact. The tibial defect was reconstructed with autograft bone from the iliac crest and a vascularised fibula. A gastrocnemius muscle flap was rotated to cover the grafts. Four patients had continuation of high dose chemotherapy following surgery and one patient had acute liver failure in the post-operative period requiring the cessation of further chemotherapy.

Results: There are three males and two females aged 10 to 18 years. The length of resection was 6.5cm to 12cm and the distance from the articular surface of the tibia to the proximal resection margin ranged from 3mm to 8mm. One patient had reattachment of the tibial tendon because the tibial tubercle had to be resected with the tumor. Pathologic examination showed greater than 90% necrosis in all patients. One patient required two additional procedures because of fracture of the vascularised fibular graft. Her leg is solidly united at 70 months follow-up. Another patient had delayed wound healing with spontaneous resolution. Two patients had contralateral epiphyseodesis to prevent a progressive limb length discrepancy. Follow-up is 13, 46, 55, 70 and 81 months since surgery. The patients are continuously disease-free. The knees in four patients are stable to medial and lateral stress; one patient has slight medial opening, and no patients exhibit anteroposterior laxity. The range of motion of all knees is complete and there is no joint narrowing. Four patients have resumed sports and two wear a brace for these activities.

Conclusion: This surgical approach resulted in excellent outcomes in a selected group of patients. Since this is a biologic reconstruction, the patient is allowed unrestricted athletic activities. There is no sign of joint deterioration after short follow-up. Further investigations are required to determine the safety of the procedure and define surgical indications.

Introduction and Aims: The treatment of bone defects secondary to congenital pseudoarthrosis of the tibia, infections and tumors is problematic. The vascularised fibular graft has been used for many years as a way to improve blood supply and successfully achieve union. Lengthening the limb prior to grafting can improve outcomes.

Method: Forty-one patients with major bone defects secondary to tumor resections, infections and congenital pseudoarthroses had reconstruction with a vascularised fibular graft. Of these, 10 patients had limb length discrepancies, which were treated by application of an external fixater for lengthening through the bone gap. Following restoration of length with an external fixater, a vascularised fibular graft was inserted to bridge the bone defect. The external fixater was not removed until union of the graft to the host bone and initial hypertrophy occurred.

Results: The 10 patients (five males and five females) were aged 2.5 to 14.5 years (mean 7.6 years). The affected bones included eight tibias, one humerus and one ulna. The limb length discrepancies ranged from three to 20cm (mean 6.44cm). The duration of lengthening prior to definitive vascularised fibular graft ranged between one to 15 weeks (mean seven weeks) in nine patients. In the patient with a discrepancy of 20cm, lengthening spanned 52 weeks. At the time of the definitive vascularised fibular graft procedure, the fixater was partially disassembled to facilitate surgery and microvascular anastomosis. The frame was then reassembled and used as the fixation device to protect the graft. The fixater was removed from seven to 24 weeks (mean 16 weeks) after definitive surgery. There were no complications during the lengthening process. However, two patients experienced non-unions, which were successfully treated by autologous bone grafts. One patient had a fracture of the vascularosed fibular graft, which healed uneventfully.

Conclusion: A staged approach to reconstruction of major long bone deficiencies leads to a better outcome than insertion of vascularised fibular grafts without addressing the limb length discrepancy. In this type of procedure, the patients not only bridged their bone defect, but achieved limb length equality as well.