Olav Reikeras1, Ragnhild Beate Gunderson1. 1. 1 Department of Orthopedics, 2 Department of Radiology, Oslo University Hospital, Rikshospitalet, Oslo, Norway.
Abstract
BACKGROUND: Appropriate orientation of the acetabular cup is an important factor for long-term results of total hip arthroplasty. For measurement of cup version cross-table lateral radiography is frequently used, but the reliability has been questioned. We compared cross table lateral radiography with computed tomography in patients that had undergone primary total hip arthroplasty. METHODS: The study was prospectively done in 117 patients (117 hips). At 3 months after total hip replacement the acetabular version was measured by cross table lateral radiography and compared to measurements by computed tomography. RESULTS: By cross table lateral radiography acetabular anteversion was on mean 13.9° with a standard deviation of 10.1° as compared to 17.8°±12.6° by computed tomography. Mean difference was -3.8 with a distribution of measurements of ±13 degrees for 95% of the cases. CONCLUSIONS: Our study shows that cross table radiography provides acceptable information for clinical use, but has limited use for precise analysis of acetabular cup version.
BACKGROUND: Appropriate orientation of the acetabular cup is an important factor for long-term results of total hip arthroplasty. For measurement of cup version cross-table lateral radiography is frequently used, but the reliability has been questioned. We compared cross table lateral radiography with computed tomography in patients that had undergone primary total hip arthroplasty. METHODS: The study was prospectively done in 117 patients (117 hips). At 3 months after total hip replacement the acetabular version was measured by cross table lateral radiography and compared to measurements by computed tomography. RESULTS: By cross table lateral radiography acetabular anteversion was on mean 13.9° with a standard deviation of 10.1° as compared to 17.8°±12.6° by computed tomography. Mean difference was -3.8 with a distribution of measurements of ±13 degrees for 95% of the cases. CONCLUSIONS: Our study shows that cross table radiography provides acceptable information for clinical use, but has limited use for precise analysis of acetabular cup version.
Entities:
Keywords:
Accuracy; acetabular component; measurement; precision; total hip; version angle
Authors: Bernard Ghelman; Christopher K Kepler; Stephen Lyman; Alejandro González Della Valle Journal: Clin Orthop Relat Res Date: 2009-03-10 Impact factor: 4.176