Acetabular Diameter Measurement Determines Proper Prosthetic Head Size in Hemiarthroplasty for Femoral Head Osteonecrosis

In hemiarthroplasty for femoral head osteonecrosis, collapse and deformity may make femoral head measurement difficult, thus, precluding the selection of an appropriate prosthetic head. We describe a method for measuring the acetabular diameter using acetabular sizing gauges to estimate the prosthetic head size. We evaluated the precision of this method and found it to be highly accurate and reliable.