The SMR reverse shoulder prosthesis in the treatment of cuff-deficient shoulder conditions.
BACKGROUND
Reverse total shoulder arthroplasty (RSA) is a relatively recent concept that provides further options in the management of cuff-deficient shoulder disorders. While early results utilizing the Delta III prosthesis (DePuy, Warsaw, IN) have been promising, there is limited data in the literature on outcomes utilizing differing prosthetic designs. We report on the outcomes of Reverse total shoulder arthroplasty (RSA) utilizing a previously unreported prosthesis, the SMR Modular Shoulder System (Systema Multiplana Randelli, Lima-LTO, Italy).


METHODS
49 arthroplasties in 48 patients who underwent Reverse Shoulder Arthroplasty with the SMR prosthesis were available for follow up. There were 10 males and 38 females with a mean age of 78.9 years (55-94) at time of operation. The most common indications were cuff tear arthropathy and osteoarthritis with cuff deficiency (66%), followed by fracture and fracture sequelae (16%).


RESULTS
At a mean 38 months follow up, 89% of patients rated their outcome as good or excellent. The mean American Shoulder and Elbow Surgeon Score was 70.1 (range 3-100), and the mean Oxford Shoulder Score 22.0 (12-47). The mean active anterior elevation was 122 degrees (range 45-180) and the mean external rotation 14.7 degrees (25-75). Inferior glenoid notching was seen in 24% of patients. There was no radiological evidence of component loosening and no reoperations.


CONCLUSIONS
Modern RSA designs give encouraging results in the treatment of cuff deficient shoulder conditions. Our early experience with the SMR RSA shows favourable outcomes and a low rate of complications.


METHODS
Level 4 Retrospective case series, no control group.
Young
Simon W
SW
Department of Orthopaedic Surgery, North Shore Hospital, Auckland, New Zealand.
Everts
Ngozi M
NM
Ball
Craig M
CM
Astley
Tim M
TM
Poon
Peter C
PC
D000369:Aged, 80 and over; D019643:Arthroplasty, Replacement / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007593:Joint Instability / Q000000981:diagnostic imaging / Q000601:surgery*; D007595:Joint Prosthesis; D008875:Middle Aged; D010147:Pain Measurement; D011336:Probability; D011474:Prosthesis Design; D011475:Prosthesis Failure; D011859:Radiography; D016059:Range of Motion, Articular / Q000502:physiology*; D020127:Recovery of Function; D018570:Risk Assessment; D000070636:Rotator Cuff Injuries; D012785:Shoulder Joint / Q000503:physiopathology / Q000601:surgery*; D018709:Statistics, Nonparametric; D016896:Treatment Outcome