Changes in load-bearing area after Ganz periacetabular osteotomy evaluated by multislice CT scanning and stereology

Acta Orthop Scand. 2004 Apr;75(2):147-53. doi: 10.1080/00016470412331294395.


Background: We used a stereologic method based on 3D CT scanning to estimate the projected load-bearing surface in the hip joint.

Patients and methods: 6 normal hip joints and 6 dysplastic hips were examined. The latter were CT-scanned before and after periacetabular osteotomy.

Results: We found that the average area of the projected load-bearing surface of the femoral head preoperatively was 7.4 (6.5-8.4) cm2 and postoperatively 11 (9.8-14) cm2, which was similar to the load-bearing surface in the normal control group. We performed double measurements and the coefficient of error of the mean was estimated at 1.6%. Due to overprojection, an overestimation of about 3.8% on the projected load-bearing surface occurred. Consequently, the stereologic method proved to be precise and unbiased.

Interpretation: Our findings indicate that this method is of value for monitoring the load-bearing area in the hip joint of patients undergoing periacetabular osteotomy.

MeSH terms

  • Acetabulum
  • Adult
  • Female
  • Hip Joint / diagnostic imaging
  • Hip Joint / physiopathology
  • Hip Joint / surgery
  • Humans
  • Imaging, Three-Dimensional
  • Joint Diseases / diagnostic imaging*
  • Joint Diseases / physiopathology
  • Joint Diseases / surgery*
  • Male
  • Osteotomy / methods*
  • Predictive Value of Tests
  • Tomography, X-Ray Computed / methods*
  • Treatment Outcome
  • Weight-Bearing