Is there a role for acromioplasty and tuberoplasty in reverse shoulder arthroplasty to improve impingement-free range of motion?

Hypothesis and Background

Lateralizing the center of rotation in reverse shoulder arthroplasty (RSA) decreases the risk of scapular notching due to inferior impingement but may limit range of motion (ROM) in abduction and forward flexion related to superior acromial impingement. Our primary hypothesis was that, using a 3-dimensional (3D) computer model, a virtual acromioplasty (with or without tuberoplasty) could improve abduction and forward flexion following RSA for cuff tear arthritis (CTA) or massive cuff tear. Our secondary hypothesis was that, based on the virtual planning, a surgical acromioplasty could be performed safely during RSA, without increasing the risk of postoperative acromial fracture.

Methods

Eighty seven patients with CTA scheduled for RSA were analyzed with a 3D software and impingement-free ROM was measured. After virtual prosthesis implantation, early acromio-humeral impingement (abduction ≤ 80° or forward flexion ≤ 120°) was observed in 25% of the cases (22/87). A virtual acromioplasty (with or without tuberoplasty) was then performed and glenohumeral ROM was measured again. Based on this 3D planning, a surgical acromioplasty (with or without tuberoplasty) was performed to improve ROM in the vertical plane in these 22 patients with early acromial impingement. Patients were followed with minimum 24 months of follow-up to assess final shoulder ROM and complications.

Results

After virtual acromioplasty alone (n = 11) or acromioplasty with tuberoplasty (n = 11), glenohumeral abduction significantly increased from 75° ± 6.9 before to 89.5° ± 23.4, and forward flexion from 119.3° ± 12 to 135.2° ± 10 (P < .001). After surgical acromioplasty/tuberoplasty, the final mean global forward flexion was 148° ± 5 and mean global abduction 150° ± 8 in these patients. At last follow-up, no acromial fracture was observed.

Conclusion

In a 3D model, early acromial impingement may limit abduction (≤80°) or forward flexion (≤120°) after virtual RSA implantation for CTA or massive cuff tear. Virtual acromioplasty (with or without tuberoplasty) shows improved ROM in abduction and flexion. In patients with early impingement, a surgical acromioplasty can be performed safely during RSA, through a deltopectoral approach, without increasing the risk of postoperative acromial fracture.