Abstract
BACKGROUND:
Bony increased-offset reverse shoulder arthroplasty (BIO-RSA) creates a long-necked scapula, providing the benefits of lateralization. Experience with allogenic bone grafting of the glenoid in shoulder arthroplasty is mainly based on its use with total shoulder arthroplasty (TSA). Therefore, our study objectives were: 1) verify if the use of BIO-RSA together with glenoid surface grafting with allogenic bone would provide similar benefits (clinical and functional) as found with autologous bone, 2) determine if allograft could be a good alternative in the absence of (good quality) autograft bone, and 3) to see if the allograft would incorporate with the native glenoid bone.
METHODS:
We included 25 patients (19 female, 6 male) in this prospective study. Indications for BIO-RSA were: fracture sequalle (n = 9), revisions (n = 11), 4-part humerus fracture (n = 1), rheumatoid arthritis (n = 1) and cuff tear arthropathy (CTA) with poor humeral head bone quality/osteonecrosis (n = 3). Mean (± SD) age 70 ± 11 years (range, 44–86). Clinical evaluation consisted of ROM, Constant scores, patient satisfaction (Subjective Shoulder Value (SSV)) and noted complications. Radiographic and CT scan evaluation consisted of bone graft healing, bone graft resorption/lysis, glenoid component loosening, inferior scapular notching, spur formation and anterior/posterior scapular notching. Mean follow-up was 34 ± 10 months (24–62).
RESULTS:
Mean active mobility improved from 50 ± 39° to 123 ± 33° (50–170°) for anterior elevation, from 2.4 ± 17° to 12.1 ± 16° (−20–40°) for external rotation, and from 1.8 ± 2 to 4.7 ± 3 points (0–8) for internal rotation. Mean Constant scores improved from 19 ± 12 to 55 ± 16 points (30–83) and from 26 ± 16% to 77 ± 24% (40–111%). Mean SSV from 21 ± 16% to 65 ± 18% (30–100%). One patient sustained an acromial fracture (treated conservatively) and one patient had breakage of screws and complete glenoid component loosening (revised to a hemi arthroplasty). In 92% of cases (23 of 25) the allograft incorporated completely, partial lysis of the bone graft (n = 5), inferior scapular notching (n = 5), spur formation (n = 7), posterior notching (n = 5).
CONCLUSIONS:
BIO-RSA with allograft bone grafting does not provide the same clinical and functional results as with autologous bone grafting. However, it does provide a good alternative in cases where humeral bone stock is not preserved and the allograft bone does incorporate with the native glenoid bone.
