CoC bearings performance on short stems

How do CoC bearings perform long-term on short stems? In a prospective study by Kim YH et al., long-term clinical and radiographic outcomes, survival rates and complication rates in patients under 50 years of age were considered. Among the total 239 patients with THA (324 hips), the most common diagnosis were osteonecrosis (50%) and dysplastic hip (34%). The patients were treated with the same ultra-short metaphyseal-fitting anatomic cementless femoral stem. 273 received a BIOLOX®delta on BIOLOX®delta wear couple (32 and 36 mm) and 51 a BIOLOX®forte on BIOLOX®forte wear couple (28 mm).

Their findings after 15.6 years mean follow-up:
➡ Survival rate of the femoral component was 99.1 %
➡ Survival rate of the acetabular component was 100%.

Two hips dislocated in the first two weeks postoperatively and were treated successfully with a closed reduction. Two hips had periprosthetic fracture after a fall. One of them loosened and was revised. Three stems (0.9%) were revised for femoral aseptic loosening. The overall results were evaluated according to the Harris Hip Score under which 86 % were classified as ‘excellent’ and 10 % with ‘good’ hip scores.

Reference: Kim YH, Park JW. Long-term outcomes of ultra-short metaphyseal-fitting anatomic cementless femoral stem in total hip arthroplasty with ceramic-on-ceramic articulation for young patients. J Arthroplasty. 2019;34(10):2427-2433. doi:10.1016/j.arth.2019.04.036.