High Hip Center Technique Using a Biconical Threaded ZweymullerA® Cup in Osteoarthritis Secondary to Congenital Hip Disease

The high hip center technique used for a deficient acetabulum is reconstruction of the hip at a high center of rotation. In the literature, there is no consensus regarding the value of this technique. We investigated whether the new-generation biconical threaded Zweymuller(A (R)) cup fixed in a high nonanatomic position in patients with arthritis secondary to congenital hip disease experienced different rates of polyethylene wear and long-term survivorship when compared with anatomically positioned cups. We studied the polyethylene wear rate and Kaplan-Meier survivorship of 104 titanium threaded Zweymuller(A (R)) cups in 88 patients (81 females), placed in 70 hips at near-normal hip center and in 34 hips at a high hip center position at a distance of 31.1 to 60 mm (mean, 39.7 mm) from the interteardrop line. Minimum followup was 2 years (mean +/- A SD, 8.6 +/- A 3.5 years; range, 2-15 years). The mean linear polyethylene wear rates in the near-normal and high hip center groups were not different (0.110 +/- A 0.050 mm and 0.113 +/- A 0.057 mm, respectively). The Kaplan-Meier 15-year cup survivorship rates with revision for any reason as an event of interest in the near-normal and high hip center groups also were not different (97.2% [95% confidence interval, 88.5%-99.3%] and 97.1% [95% confidence interval, 73.8%-99.3%], respectively). The high hip center technique using a biconical threaded Zweymuller(A (R)) cup in patients with arthritis secondary to congenital hip disease results in a polyethylene wear rate and long-term cup survivorship comparable to those observed in anatomically positioned cups. Level III, therapeutic study. See the Guidelines for Authors for a complete description of level of evidence.