Treatment of massive acetabular bone loss and pelvic discontinuity with a custom triflange component and ilio-sacral fixation based on preoperative CT templating. A report of 2 cases.

Revision rates for total hip arthroplasty are increasing and pelvic discontinuity is estimated to be present in 1% to 5% (Berry). Discontinuity is defined as a separation of the cephalad portion of the pelvis from the caudad portion (AAOS Type IV defects). This results from bone loss secondary to osteolysis, infection, fracture, or mechanical loosening. The goals of revision surgery in this setting are to obtain secure fixation of the acetabular component with or without union of the discontinuity. Many methods exist for treating this problem. Results with allograft and cage fixation have generally been poor (Berry, Hansen). More favourable outcomes have been reported using either a cup cage technique or custom triflange (Gross, Christie). The custom Triflange component is designed based on preoperative imaging with CT scan to manufacture a custom titanium implant to address the patient's specific bone loss pattern and obtain secure fixation in the ilium, pubis, and ischium. However, we have encountered cases of acetabular discontinuity with massive pelvic bone loss in which bone stock in the ilium was insufficient to provide support for proximal fixation of a conventional custom triflange component. Currently in the trauma patient population posterior pelvic ring disruptions are being treated with ilio-sacral screw fixation. The sacrum provides a source of secure bony fixation for these injuries. We report on 2 patients with pelvic discontinuity and massive bone loss using a technique to obtain proximal fixation of a custom triflange component into the sacrum.

Retrograde reamed femoral nailing.

Closed, reamed, antegrade nailing remains the standard of care for femoral shaft fractures. This technique however, may be less attractive in the management of femoral shaft fractures associated with (a) ipsilateral acetabular, pelvis, or femoral neck fractures; (b) polytrauma requiring multiple simultaneous surgical procedures; and (c) pregnancy. We now report on our experience with the retrograde femoral nailing as a treatment option in these situations. Between 4/88 and 10/90, 29 retrograde femoral nailing in 24 patients were attempted. Average age was 29.3 (16-74) years. Five fractures were open. Fracture location was isthmal in 14 and infraisthmal in 15. The comminution was classified according to Winquist and Hansen: I(10), II(7), III(7), and IV(5). Nailing was possible in 28/29 cases. Insertion was made through an extraarticular medial condylar portal. Nail diameter ranged from 10 to 13 mm. An AO Universal Femoral Nail was used in the first 11 cases; all subsequent fractures were stabilized using an AO Universal Tibial Nail because its design appeared better suited to this technique. Follow-up was possible for 25 fractures in 21 patients and averaged 16.0 (range, 11-27); months 23/25 (92%) fractures healed within 12 weeks. No case was associated with an infection, loss of reduction, or nail failure. Knee flexion averaged 122 degrees; only two knees had an extensor lag of > 5 degrees. Intraoperative complications included three cases of crack propagation at the insertion site, and four infraisthmal malreductions (two valgus, two flexion). Based on these results, we feel that retrograde reamed femoral nailing is a suitable alternative to antegrade nailing and should be considered in situations where proximal access is neither possible nor desirable.