Between June 1991 and January 1995, 42 hydroxyapatite-coated CAD-CAM femoral components were inserted in 25 patients with inflammatory polyarthropathy, 21 of whom had juvenile idiopathic arthritis. Their mean age was 21 years (11 to 35). All the patients were reviewed clinically and radiologically at one, three and five years. At the final review at a mean of 11.2 years (8 to 13) 37 hips in 23 patients were available for assessment.

A total of four femoral components (9.5%) had failed, of which two were radiologically loose and two were revised. The four failed components were in patients aged 16 years or less at the time of surgery. Hydroxyapatite-coated customised femoral components give excellent medium- to long-term results in skeletally-mature young adults with inflammatory polyarthropathy. Patients aged less than 16 years at the time of surgery have a risk of 28.5% of failure of the femoral component at approximately ten years.

Aim: To assess the mid term clinical and radiographic results of the ABG II uncemented hip arthroplasty.

Methods: All patients treated consecutively with the ABG hip (n=42) as a primary total arthroplasty were identified and contacted. The response rate was 89% (n=38). Responders were assessed by means of the Merle D’Aubigne1 (MDA) scoring system and radiographs taken. Radiographic assessment was carried out by two independent assessors who were blinded to the clinical outcomes. An overall assessment of loosening was made based on seven radiographic signs.

Results: The mean age of patients was 61 years (range: 44–73). Average MDA score at present day follow up was 17.6 (maximum 18) and did not decline with time post surgery. There was no evidence of radiographic loosening in any hips. There was one revision for a peri-prosthetic fracture sustained 10 days post op. Survivor-ship (all cases) was 100% for cup and 97.37% for stem at 7 years. There was no evidence of early cup loosening.

Discussion A recent study has shown unacceptably high rates of cup failure secondary to premature wear and osteolysis2 but this has not been evident in this series. Although this study did show cup eccentricity in 4 patients (representative of liner wear) there was no clinical nor radiographic evidence of cup loosening, osteolysis or failure.

Conclusion In the medium term we have shown excellent clinical outcomes with no evidence of early loosening of the ABG II hip prosthesis

We have reviewed 13 operations on 11 patients using curettage and polymethylmethacrylate cement for giant-cell tumour of bone (GCT) to assess the value of radiology in the early detection of recurrence. There were four recurrences, the most specific radiological sign on plain radiography was lysis of 5 mm or more at the cement-bone interface. This preceded clinical signs by a mean of four months and was identified at a mean of 3.75 months after operation. There was not always a complete sclerotic margin around the cement, but when it was present, there was never evidence of recurrence. MRI was helpful in assessing cases with evidence of recurrence.

Frequent surveillance with plain radiography should continue for one year after operation irrespective of clinical signs of recurrence. When the appearance of the plain radiographs suggests recurrence, MRI should be performed and followed by image-guided needle biopsy.