Spontaneous recurrent dislocation after primary Birmingham hip resurfacing: a rare complication in a 44-year-old man.

Dislocation is a rare complication of hip resurfacing in young people. This is thought to be due to the stability imposed by a large-diameter head [Stulberg BN, Trier KK, Naughton M, et al. Results and Lessons Learned from a United States Hip Resurfacing Investigational Device Exemption Trial. J Bone Joint Surg Am 2008;90:21]. We report an isolated case 1 week post-Birmingham hip resurfacing in a 44-year-old man without any history of trauma or infection. We note that due to massive periacetabular and femoral neck osteophyte formation and loss of normal bony anatomical landmarks, the version of the acetabular component may have been slightly retroverted. Due to marked narrowing of the femoral neck and head proximally, a cone-shaped proximal femur was found and felt to be unsuitable for direct resurfacing without prior shortening to allow fitting of the appropriate-sized Birmingham hip resurfacing femoral component. This was done successfully, but resulted in slightly reduced femoral neck offset of approximately 10 mm, compared to the native hip. We suspect this reduced offset contributed significantly to the 2 dislocations. We recommend careful preoperative planning and case selection to avoid this complication in similar patients.