RESULTS OF CHARNLEY’S HEAVY AND EXTRA-HEAVY FLANGED 40 STEM IN TOTAL HIP REPALCEMENT. – 9 TO 22 YEARS FOLLOW-UP.

Abstract

Aim: The dorsal flange stem was introduced following reports of stem fracture using the Charnley “flat-back” stem. This retrospective study reports the outcome using the Flanged Charnley stem in total hip replacement.

Materials and methods: Between January 1983 to December 1996, 1170 cemented total hip replacements (915 patients) were performed using the flanged Charnley stem. The main indications were osteoarthritis, rheumatoid arthritis and avascular necrosis. There were 532 females and 383 males aged 32 to 83 years (average 70.2 years). 612 patients were alive at an average follow-up of 16.6 years (9 to 22 years). All operations were performed by the trans-trochanteric or antero-lateral approach. Patients were evaluated using the Charnley’s modification of Merle d’Aubigne system.

Results: All patients had an improvement in function following the operation. Aseptic loosening of the stem was noted in 32 patients. Survivorship to revision of the femoral stem was 94% at 10 years (95% CI, 89%–99%) and 90% (95% CI, 81%–99%) at 15 years. The common complications included dislocation, wire breakage and trochanteric non-union. Femoral stem fracture resulted in 1 patient requiring stem revision.

Conclusion: The use of the Flanged Charnley stem in total hip replacement gives good long term outcome.