This article is more than 5 years old. Information may no longer be current.
Long-term follow-up with HA-coated components promising
Two retrospective studies showed good results in hip revision surgery.
Click Here to Manage Email Alerts
MANCHESTER, England
— Long-term studies of hydroxyapatite-coated components showed good
results for hip revision surgery, according to two presentations at the recent
British Orthopaedic Association Annual Congress here.
One study assessed clinical and radiological outcomes using the JRI Furlong HA coated femoral component in 120 consecutive revision hip arthroplasties in 107 patients. The mean age of patients was 71. The study was performed at Worthing and Southlands NHS Trust, England.
Sameer Singh, FRCS, reported “excellent medium and long-term clinical, radiological and survivorship results” using the JRI hydroxyapatite ceramic coated femoral component. The cumulative survival was 100% at 11 years for aseptic loosening.
Singh is a specialist registrar from the South West Thames Orthopaedic rotation.
Harris hip score
|
Ninety-seven patients had the cup and the stem revised, with most of those cemented. |
All patients in the study received the JRI hydroxyapatite ceramic-coated component. Ninety-seven patients had both the cup and the stem revised, and the majority of components removed were cemented. The mean time between primary and revision surgery was 9.6 years.
Patients were assessed using the Harris hip score. Overall, all patients had satisfactory scores. After review, the mean Harris hip score was 85; 86% of patients had a score greater than 80.
Radiographs were examined by the study authors who were blinded to the clinical results. Investigators noted any signs of new bone formation, osteolysis and any radiolucent markers.
All stems showed signs of osteointegration and stable bone ingrowth. “HA-coated components encouraged bone ingrowth in the prosthesis,” Singh said.
Second trial
|
HA coated components were found to be suitable implants for revision of cemented hip arthroplasties. |
The second study reported on the long-term outcome of the revision of cemented hip arthroplasties using the JRI Furlong HAC coated femoral and acetabular components.
Raghu Raman, MRCS, of Dewsbury Hospital, said the study period for this retrospective chart analysis was from 1988 to 1996, with 86 hips in 82 consecutive patients. The mean age of patients at revision was 78, with the range 58 to 89 years. Forty-nine patients were women.
Mean time from to revision from the index hip replacement was eight years. The major reasons for revision were aseptic loosening and seven infections. The senior investigator performed more than 70 of the hip surgeries, Raman said.
Several measures were used for the outcome, including the Oxford, Harris and Charnley scores. Functional outcome was measured using the EuroQol 5D (EQ-5D), a self-rated questionnaire; the VAS score measured level of pain.
Mean follow-up was 12.6 years; minimum follow-up was at least seven years.
Long-term results
The average Harris hip score at last follow-up was 82; the Oxford score was 24; the Charnley score was 5 for pain, 4.9 for movement and 4.2 for mobility. EQ-5D description and health scores were 0.69 and 79.
Mean linear polythene wear was 0.05 mm per year; mean subsidence was 1.6 mm, Raman said. Overall survival at 12 years was 93%, with removal or repeat revision of either component for any reason as the endpoint.
With an endpoint of definite or probable loosening of the femoral component, survival was 96% at 12 years. No stem was revised for aseptic loosening, Raman said. Survival was 95% at 12 years for the endpoint of definite or probable loosening of the acetabular component.
“From our experience, we found that the HA-coated endoprosthesis is a suitable implant for revision of cemented hip arthroplasties. Furthermore, there is excellent survival and good functional outcome with use of this prosthesis for revision hip arthroplasty,” Raman said.
For more information:
- Singh S, Trikha P, Raynham O, et al. Hydroxyapatite coated femoral stems in revision hip surgery.
- Raman R, Kamath RP, Angus PD. Revision of cemented hip arthroplasty using HA-coated endoprosthesis: a seven to fifteen year follow-up. Both presented at the British Orthopaedic Association Annual Congress. Sept. 14-17, 2004. Manchester, England.