gms | German Medical Science

Objectives: To explore the impact of head-acetabulum relationship (HAR) on prognosis of non-traumatic osteonecrosis of femoral head (NONFH) in earlier stages by MATrix LABoratory (MATLAB), so as to guide clinical practice.

Methods: Plain radiography of 20 patients (40 hips) with NONFH were treated. Radiographs were taken at onset, 3 month, 1 year and 5 years after diagnosis until surgery was performed. The HAR within weight-loading portion is estimated by computer-aided, MATLAB. Calculated region is assigned in particular setting and then establish a function model to get the relevant parameters of HJR. Mechanical equilibrium conditions of HAR were be analyzed and categorized. Rank sum tests were used to demonstrate the difference HARs with the impact on Harris hip score.

Results and Conclusion: Harris hip score correlated with HAR (P<0.01). The results of rank sum tests for several independent samples showed significant difference in HAR among pain groups (P<0.01). The normal HAR is range from 0.98 to 1(covariance) even the necrosis area is existed. When the covariance is less below 0.98(medium: 0.98-0.94, serious: 0.94-0), pain appears and pathological changes will be detected. And all these changes can be confirmed by straight-line fit of each portion of HAR. Conclusion: There is definite curative efficacy for the radiographic evaluation of head-acetabula relationship within weight-bearing area, as it could be believed sensitivity to predict pathological advancement in NONFH. The reason is presumably that disease progression result from unmatched HAR, including femoral head collapse, wearing articular cartilage subchondral fracture, femoral acetabula impingement developmental dysplasia and so on. The condition of HAR can be used as a parameter for the appraisal of advancement of disease, the judgment of treatment result and the survival quality of patience.