Narrowing of the femoral neck after resurfacing arthroplasty of the hip: a comparison of cemented and uncemented femoral components.

We performed a radiographic review of a consecutive series of 87 resurfacing arthroplasties of the hip, performed between 2004 and 2006. There were 54 cemented femoral components and 33 uncemented femoral components. All of the procedures were performed by the same surgeon using the same approach. There was no difference between the groups with regards to gender, age, pre-operative diagnosis and the average diameter of the components. The primary outcome measured was the neck-prosthesis ratio on standard anterior-posterior pelvis radiographs taken post-operatively and at a minimum follow up of two years. The difference between the immediate post-operative ratio and the most recent radiograph was statistically significant in patients with cemented femoral components (p=0.006), but not in the group with uncemented components (p=0.173). We have demonstrated a difference in narrowing of the femoral neck between cemented and uncemented femoral components in the first two years following surgery.