[Diagnosis of hip prosthesis loosening--sensitivity of clinical parameters]

In order to establish a strategy for early diagnosis of aseptic loosening of total hip arthroplasty (THA) physical examination, patient's assessment and radiographs were analysed.

Pain, self assessment, physical examination and mobility were examined according to a standard examination protocol in 428 hips of 297 patients after cementless total hip arthroplasty (THA). These findings were compared with the radiographic finding of the hip. Sensitivity and specifity of objective and subjective parameters were analysed.

The clinical outcome of THA's is assessed by pain and physical examination. Nearly all hip scores are based on these parameters. In this study sensitivity and specificity of all parameters analysed were unsatisfactory compared with the radiographic finding. Although we found some correlations between clinical and radiological data, clinical data alone are not sufficient for exclusion of THA loosening, especially for loosening of the acetabular component, as there was no clear distinction between the group of radiographically loosened (43 acetabular cups and 4 stems) and intact endoprostheses.

We conclude, that physical examination and pain history are not sufficient to exclude loosening of cementless THA's. Radiographic examination is essential for the assessment of THA's, even in painfree patients.