Short-term rates of radiolucency after primary total shoulder arthroplasty using a cementless metal-backed pegged polyethylene glenoid

Abstract

Background: Total shoulder arthroplasty has shown good clinical efficacy in treating primary and secondary degenerative conditions of the glenohumeral joint. Glenoid loosening, however, remains the commonest cause of failure. The purpose of this study was to investigate the rate of radiographic periprosthetic lucency associated with the use of an uncemented, pegged, metal-backed polyethylene glenoid component. Materials and methods: A retrospective, single-centre study using the Epoca (Synthes, Paoli, Pennsylvania) metalbacked glenoid component. Operations were performed by two experienced consultant upper limb surgeons. Radiographs were analysed for immediate post-operative component seating and periprosthetic radiolucent lines at predefined regular post-operative intervals. Intra-and inter-observer reliability was assessed to improve validity of results. Results: Mean age and follow-up was 72 (48-91) years and 2.5 years (2-5), respectively. Main indications for total shoulder arthroplasty were primary osteoarthritis, rheumatoid arthritis, revision for failed hemi-arthroplasty and acute fracture. Ninety-six per cent of components were completely seated post-operatively. Fifty-four (95%) of the 57 shoulders had no periprosthetic radiolucent lines at most recent follow-up. Complete post-operative glenoid seating was significantly associated with the absence of later periprosthetic radiolucency (p < 0.01). Conclusion: This study reports low early radiolucency rates with the pegged, uncemented, metal-backed polyethylene glenoid prosthesis used. Excellent post-operative glenoid seating is associated with a significantly lower rate of radiolucency. Longer follow-up data are required to confirm these early promising results. Level of evidence: Therapeutic, level IV.

Medium-term rates of radiolucency after primary total shoulder arthroplasty using a cementless metal-backed pegged polyethylene glenoid

“…Any radiolucency was defined using the modified Franklin method (Table 2), 24 and a modified Lazarus classification adapted for a two pegged component was utilised named the 'Bristol radiolucency classification' (BRC) (Figure 1). 22 Each assessor undertook two rounds of radiographic assessment with blinding of round one data collection for round two.…”

“…[13][14][15][16][17][18][19][20][21] We previously reported short-term radiographic results in an uncemented, pegged, metal-backed glenoid component which demonstrated positive early results with no failures and minimal radiolucency. 22 This paper aims to expand upon those early results with the results of medium-term follow-up.…”