74. CEMENTED VERSUS UNCEMENTED FIXATION OF HUMERAL COMPONENTS IN TOTAL SHOULDER ARTHROPLASTY FOR OSTEOARTHRITIS OF THE SHOULDER

Abstract

Purpose: This prospective, randomized double-blinded clinical trial compared cemented fixation of the humeral component to uncemented/tissue-in-growth fixation in total shoulder arthroplasty for primary osteoarthritis of the shoulder.

Method: All patients presenting with primary osteoarthritis of the shoulder requiring replacement were screened for eligibility. Patients were randomized in the operating room after glenoid preparation to the cemented or uncemented group by a computer-generated, stratified randomization procedure. Outcome measures included disease specific QOL assessment (WOOS), SF-12, ASES, MACTAR, radiographic evaluation of component fixation, operative time, complications and revision surgery. Patients were assessed by a blinded evaluator in post-operative intervals of 2 and 6 weeks, and 3, 6, 12, 18, and 24 months. The primary endpoint was the WOOS score at 2 years.

Results: One hundred and sixty-one patients were consented and randomized for the study. There were 80 patients in the cemented and 81 patients in the uncemented group. At baseline, the groups were alike with regards to demographics and baseline evaluations. The WOOS scores at post-operative intervals of 12, 18 and 24 months showed a significant difference (p=0.009, 0.001, 0.028 respectively) in favour of the cemented group. The cemented group also had better strength (3 m p=0.038, 12 m p= 0.036, 18 m p=0.051, 24 m p=0.053) and forward flexion (6m p=0.031, 12 m p=0.04). As expected, the operative time was significantly less for the uncemented group (C = 2.26h +/−.63; U = 1.69h +/− 1.9, p= 0.03).

Conclusion: These findings provide the first evidence that cemented fixation of the humeral head provides better quality of life, strength and ROM than uncemented fixation. This was a Tier 1 Project of the JOINTs Canada group.