Single-incision Extraperiosteal Triple Innominate Osteotomy: Outcomes of an Updated Technique

Since its original description, the triple pelvic osteotomy has undergone several modifications and refinements most often utilizing 3 or 2 incisions. Recently, a single-incision extraperiosteal technique has been described; however, little data exist on the outcomes of this procedure.

All patients undergoing single-incision triple osteotomy from 2 centers were retrospectively reviewed. Demographic data, underlying diagnosis, and preoperative radiographic data were recorded. Intraoperative details including estimated blood loss and type of postoperative immobilization were noted. Over the follow-up period, complications were recorded as were radiographic outcomes including lateral center edge angle, acetabular index, migration percentage, continuity of Shenton's line, and time to union.

Twenty-eight hips (in 24 patients) underwent surgery at a mean age of 9.3 years (range, 6.5 to 13.8 y). Diagnoses included Trisomy 21 (9), developmental dysplasia of the hip (5), Charcot-Marie-Tooth (3), and neuromuscular disease (9) among others. The mean estimated blood loss was 135 mL (±98 mL) and most patients were immobilized in an abduction brace or single-leg spica cast for an average of 7.6±2.2 weeks after surgery before weight-bearing was advanced. At a mean follow-up of 3.0±2.2 years, the lateral center edge angle improved from an average of 1±14 degrees preoperatively to 35±7 degrees, the acetabular index from 27±11 degrees to 2±5 degrees, and the migration percentage from 44%±21% to 3%±5%. Fourteen hips had frank instability before surgery and 20 had a break in Shenton's line >5 mm. At most recent follow-up, all but 1 hip was stable (93%) and all had restoration of Shenton's line (100%). Radiographic union occurred at a mean of 14 weeks (±11 wk). One patient developed an ischial nonunion that underwent further surgery, 1 had premature closure of the triradiate cartilage, and 1 patient with transverse myelitis developed Charcot arthropathy. There were no other complications in this series.

In this dual-center retrospective series, the single-incision triple innominate osteotomy was extremely effective for improving acetabular coverage and stabilizing unstable hips in a variety of underlying diagnoses with an acceptably low rate of complications.

Level IV-case series.