The outcome of patients with hinge abduction in severe Perthes disease treated by shelf acetabuloplasty.

Background: The management of patients with Perthes disease remains controversial. In children with hinge abduction and the potential for remodeling, we have performed a shelf acetabuloplasty, in an effort to contain the hip and allow remodeling. We report our medium-term results in a consecutive series of 27 children with severe Perthes disease and arthrographically proven hinge abduction. This is the first report in the English literature to look specifically at the results of treating patients with hinge abduction in severe Perthes disease by shelf acetabuloplasty.

Methods: Twenty-seven consecutive children with unilateral Perthes disease and arthrographically proven hinge abduction were treated with a shelf acetabuloplasty. These patients have been prospectively reviewed with a clinical examination and radiographic assessment including Catterall, Salter Thompson, and Herring's lateral pillar classification. Radiological measurements included percentage acetabular cover, medial joint space, and femoral head size ratio.

Results: The mean postoperative follow-up was 62 months (range, 26-125 months). All patients were Catterall grade III or IV and lateral pillar grade B or C and had arthrographically proven hinge abduction at the time of surgery. At final follow-up, 14 hips were Stulberg grades 1 and 2; 10 hips, grade 3; and 3 hips, grades 4 and 5. The medial joint space decreased from a preoperative ratio of 1.9 to 1.4 (P = 0.002), and the percentage acetabular cover increased from 81% preoperatively to 97% postoperatively (P < 0.001).

Conclusion: These results suggest overall good outcomes from a group of patients with severe Perthes disease as measured by the Stulberg grading when compared with historical controls. We suggest that shelf acetabuloplasty is a straight forward surgical procedure with good medium-term results in patients with severe Perthes disease who have proven hinge abduction preoperatively.

Level Of Evidence: Level IV case series.