Revision arthroplasty in periprosthetic fractures of the proximal femur.

OBJECTIVE: Hip revision arthroplasty of a loose stem in the case of Vancouver type B2 and B3 periprosthetic fractures and cerclage wiring of the femoral shaft. INDICATIONS: Vancouver type B2 and B3 periprosthetic fractures of the proximal femur. CONTRAINDICATIONS: Periprosthetic joint infection. Interprosthetic femoral fractures between the ends of hip and knee prosthetic stems that require total replacement of the femur. SURGICAL TECHNIQUE: Extended posterolateral approach to the tip of the fracture. Exposure along the septum intermusculare laterale with ligation of the perforating vessels below the fracture. Longitudinal osteotomy of the proximal fragment above the linea aspera using an oscillating saw under cooling. Ventral proximal osteotomy at the corner of the vasto-gluteal sling after short muscular incision using an osteotome chisel. Opening of the proximal fragment with lifting up of the bony flap like a transfemoral approach. Removal of the loosened prosthetic stem and possibly the cement. Preparation of the distal fixation zone of the modular cementless revision stem in the isthmus of the femur distal of the fracture. Implantation of the distal component of the modular cementless revision stem. Use of additional distal interlocking screws in cases of destroyed isthmus with a fixation zone of less than 3 cm for the distal prosthetic component. Trial reposition after combination with the proximal trial component in situ. Assembly with the original proximal component in situ. Reposition with the original proximal component. Wound closure. POSTOPERATIVE MANAGEMENT: Thrombosis prophylaxis, physiotherapy, gait training with partial loading of the limb at 10 kg for a period of 6 weeks with hip flexion limited to 70°. Then, free range of movement and increased loading by 10 kg per week.
RESULTS: In all, 23 patients with periprosthetic fractures of Vancouver type B2 (15 patients) and type B3 (eight patients)-in 15 women and eight men in the age range of 70.7 ± 12.2 (42-88) years-were followed up for at least 5 years. All fractures healed with a mean time of 14.4 ± 5.3 weeks. No cases of subsidence of the stem were observed and, according to the classification of Engh et al. concerning the biological fixation of the stem, there was bony ingrowth fixation in 21 cases and two cases of stable fibrous fixation. One dislocation occurred and there were no cases of intraoperative fracture. The Harris Hip Score rose continually following the operations: from a 3-month postoperative score of 65.0 ± 16.8 points, it rose to 86.9 ± 16.2 points after 24 months and to 89.0 ± 14.3 points after 5 years. According to the classification of Beals and Tower, all results were rated as excellent, i.e., the prefracture functional status was restored in all cases.