[Clinical outcomes of total hip arthroplasty after previous hip arthrodesis]

To describe the clinical results of conversion of an arthrodesis of the hip to a total hip arthroplasty (THA) at the Erasmus MC, Rotterdam, the Netherlands.

Retrospective study.

Data were collected from the case notes of patients who had undergone conversion ofarthrodesis of the hip to a total hip prosthesis between 1 January 1985 and 31December 2003. This was a total of 13 patients, 1 of whom had died and 2 of whom were excluded because of dementia and severe psychiatric disorder respectively. The remaining 10 patients (5 men and 5 women) were sent the Short form-36 quality-of-life questionnaire and asked, if, in hindsight, they would undergo the operation again. Their hip function was assessed using the Harris Hip Score (HHS) and the weakness of the gluteus muscles using Trendelenburg's test. The preoperative and most recent postoperative X-rays of the pelvis were evaluated.

Median age at the time ofTHA was 45 years (range: 21-62). THA was done median 15 years (range: 2-50) after arthrodesis. Follow-up was done median 5 years (range: 0-18) after THA. The main reasons for conversion were ipsilateral knee pain and low back pain, which both improved after conversion. The median HHS was 75.0 (range: 44.7-99.4) and the Trendelenburg test was positive in 5 patients. 6 patients had heterotopic ossification without limitation in joint range. 9 patients confirmed they would undergo the operation again.

Arthrodesis ofthe hip was a reasonable treatment option for young patients with monoarticular hip disease.