[Proximal and total femur replacement].

OBJECTIVE: Reconstruction of segmental bone defects of the proximal femur following wide tumor resection or revision arthroplasty. INDICATIONS: Aggressive benign or primary malignant bone tumors of the proximal femur; destructive metastases; massive segmental bone defects of the proximal femur; periprosthetic fractures. CONTRAINDICATIONS: Local infection; very short life expectancy (< 3 months); massive deficiency of acetabular bone stock. OPERATIVE TECHNIQUE: Anterolateral approach. Exposure and detachment of the iliopsoas and gluteus medius muscle from the proximal femur with a sufficient safety margin to the bone; distal transsection of the vastus lateralis/intermedius and rectus femoris muscle according to the extraosseous tumor extension; distal femur osteotomy al least 3 cm beyond the farthest point of tumor extension; in case of total femur replacement, additional lateral arthrotomy of the knee with resection of the ligaments and menisci; reaming of the medullary canal after securing the shaft with a Verbrugge clamp; trial assembly and reduction followed by the definitive implantation of the prosthesis with adjustment of the femoral neck anteversion in 5° increments; soft tissue reconstruction and fixation to an attachment tube covering the prosthesis; in case of total femur replacement, the preparation of the tibia is followed by the coupling of the tibial and femoral components. POSTOPERATIVE MANAGEMENT: Infection prophylaxis, 20 kg partial weight bearing, continuous passive motion.
RESULTS: A total of 20  patients with proximal femur replacement and 2 patients with total femur replacement implanted between June 2007 and December 2011 were retrospectively reviewed. Three patients had primary malignant bone tumors, while 19 patients underwent resection for metastatic disease. The mean age at surgery was 62.0 ± 18.1 years (18-82 years). Fifteen patients with a mean follow-up of 20.3 ± 17.2 months (4-51 months) were studied. Among the 22 cases, periprosthetic infection occurred in 3 patients (13.6%), dislocation in 2 patients (9.1%). Evaluation of the functional outcome in 15 patients using the MSTS score by Enneking revealed 3 very good (20%), 4 good (26.7%), 6 fair (40%), and 2 poor (13.3%) results.