Outcome of hip resurfacing arthroplasty in patients with coxarthrosis secondary to Crowe’s types I and II developmental hip dysplasia

Background
Arthritis secondary to developmental hip dysplasia is a surgical challenge because of the anatomic abnormalities, which increase the complexity of any hip arthroplasty. Hip resurfacing has many theoretical advantages compared with conventional hip arthroplasty, especially for young and active patients. These advantages include minimal bone resection, normal femoral loading, avoidance of stress shielding, maximum proprioceptive feedback, reduced risk of dislocation, easy revision, and reconstruction of normal anatomy.
Patients and methods
Twenty-six consecutive patients (33 hips) with osteoarthritis secondary to developmental dysplasia of the hip of Crowe types I and II underwent metal-on-metal hip resurfacing through a modified lateral approach of Hardinge, taking care to protect the medial femoral circumflex artery and its retinacular branches over the femoral neck. The average age of the patients at the time of surgery was 62.8 years (range 30–73 years). Five (19%) patients were men and 21 (81%) were women. The mean follow-up was 4.8 years, range 1.8–10.3 years.
Results
Four patients developed heterotrophic ossification, which required excision because of persistent pain in one patient. Three patients had painful trochanteric bursitis; all responded well to local steroid injections. The Harris hip score improved from a mean of 52.2–97.4. There were no major complications, for example, dislocation, fractured neck of femur, loosening, infection, or symptomatic deep venous thrombosis.
Conclusion
Despite safety warnings, hip resurfacing remains an effective option in certain subgroups of hip dysplasia when it is performed with special precautions.