Aims: Leg length discrepancy is a well-recognised complication after total hip arthroplasty. However, the effect of using a cemented or uncemented femoral component on leg length has not been previously investigated. The aim of our study was to assess leg length discrepancy following total hip arthroplasty using a cemented femoral component and to compare this with an uncemented femoral component.

Patients and method: We included 140 patients who had undergone a primary total hip arthroplasty in our study. All patients received an uncemented Duraloc acetabular cup (Depuy, Leeds, UK). Our uncemented group consisted of 70 consecutive patients who had received an uncemented Accolade femoral prosthesis (Depuy, Leeds, UK). Our cemented group included 70 patients who had received a cemented Ultima femoral prosthesis (Depuy, Leeds, UK). Leg lengths were measured from radiographs by two independent observers using a validated assessment method, pre-operatively and at six months post-operatively. Clinical outcome was assessed using Harris hip scores.

Results: The mean age of the patients was 68 years for the uncemented group and 56 years for the cemented group. The overall leg length discrepancy was mean 5.7mm (range 0 to 26mm). The uncemented group had an increase in leg length discrepancy post-operatively compared to the cemented group (6.4mm vs 4.2mm), p< 0.05. There was no significant difference in Harris hip scores between the uncemented and cemented groups either pre-operatively (37.4 vs 38.7) or at 6 months postoperatively (77.9 vs 78.7 respectively).

Conclusion: We found a significant increase in leg length discrepancy after total hip arthroplasty using an uncemented femoral prosthesis compared with a cemented femoral prosthesis. This was detectable radiologically but did not affect clinical outcome. Patients should be informed about the risk of leg length discrepancy before total hip arthroplasty particularly if an uncemented femoral prosthesis is used.

Aims: Resurfacing arthroplasty of the hip is increasing in popularity. Recently concerns have been raised about resorbtion of the femoral neck after hip resurfacing, which may increase the risk of femoral neck fracture. We conducted a study to assess the degree of femoral neck resorbtion after using a cemented femoral component at hip resurfacing arthroplasty and to compare this with an uncemented femoral component.

Patients and Methods: We included 130 patients who had undergone a hip resurfacing arthroplasty in our study. Our uncemented group included 70 consecutive patients who had received an uncemented Cormet hip resurfacing arthroplasty (Corin, Cirencester, UK). Our cemented group included 60 patients who had received a cemented Birmingham hip resurfacing arthroplasty (Smith and Nephew, Cambridge, UK). All patients were regularly followed up for a minimum of two years. Clinical outcome was assessed using Harris hip scores. Femoral neck resorbtion was assessed by measuring the cup-neck ratio on post-operative radiographs by two independent observers.

Results: The mean age of the patients was 50.7 years for the cemented resurfacing group and 51.5 years for the uncemented resurfacing group. No difference was found in Harris hip scores between the two groups at any of the follow-up periods. The overall survival rate at two years was 100% for the cemented group and 98.6% for the uncemented group. There was however, a significant increase in femoral neck resorbtion for the cemented resurfacing group compared to the uncemented resurfacing group (median cup-neck ratio 1.11 vs. 1.04), p< 0.0001

Conclusion: We found a significant increase in femoral neck resorbtion with the use of a cemented femoral component at hip resurfacing arthroplasty compared with an uncemented femoral component. This may increase the risk of femoral neck fracture and could affect the long-term outcome if a cemented femoral component is used.