Preoperative digital templating of Birmingham hip resurfacing

The aim of our study was to determine the usefulness of preoperative digital templating of Birmingham hip resurfacing (BHR). This prospective cohort of 30 consecutive Birmingham hip resurfacings was templated digitally by two senior hip arthroplasty fellows (GM, JG) independently. A blinded observer then collated information on the actual implant sizes intraoperatively and used this to statistically analyse the correlation (Interclass correlation coefficient) between the digitally templated implant sizes and the actual implant sizes used. A significantly high rate of coincidence between digitally templated estimates and the actual implant sizes was noted for both groups of templates. The Intra class correlation coefficient (ICC) for the acetabular cup in the two groups were 0.798, p=0.013 and 0.870, p=0.0001. For the femoral component, the ICC values in the two groups were 0.888, p=0.005 and 0.784, p=0.003. Similarly a high reliability of digital templating was noted for both acetabular (0.823, 0.888) and femoral components (0.777, 0.8132). In conclusion, digital templating can reliably estimate implant sizes in Birmingham hip resurfacing.