Short flat-tapered cementless stem total hip arthroplasty provides favourable mid-to long-term clinical and radiological outcomes in elderly patients.

Abstract

Short cementless stems are increasingly used in total hip arthroplasty owing to potential advantages such as bone preservation, optimised load transfer, and reduced surgical invasiveness. However, their fixation reliability in osteoporotic bone remains a concern, and evidence regarding outcomes in elderly patients is limited. This study compared mid-to long-term outcomes of a flat-tapered short cementless stem in patients aged ≥75 years and ≤60 years, hypothesising that results in the elderly would be comparable with those in younger patients. We retrospectively reviewed 350 primary total hip arthroplasties performed between 2010 and 2021 using a titanium, porous, plasma-sprayed, flat-tapered cementless stem (Taperloc Microplasty™), restricted to Dorr type A or B femora. Patients aged ≥75 years comprised the elderly group, and those ≤60 years formed the younger group. Clinical outcomes were evaluated with the modified Harris Hip Score. Radiographic assessments included stem alignment, fixation stability, subsidence, radiolucent lines, cortical hypertrophy, and stress shielding. Kaplan-Meier survival analysis was performed with revision for any reason as the end-point. The analysis included 45 hips in the elderly and 132 hips in the younger group, with mean follow-up of 6.2 and 7.7 years, respectively. The modified Harris Hip Score improved significantly in both groups. All stems achieved bone ingrowth fixation. Posterior angulation was more frequent in the elderly, whereas distal cortical hypertrophy was more common in the younger group. Ten-year survival was 100 % in the elderly and 98.1 % in the younger group, with no significant difference. Short, flat-tapered cementless stems provided durable outcomes in elderly patients with Dorr type A or B femora. These findings suggest that short cementless stems may be a reasonable option for carefully selected elderly patients undergoing total hip arthroplasty.