Does bony increased-offset reverse shoulder arthroplasty decrease scapular notching?

作者：Athwal George S^*; MacDermid Joy C; Reddy K Murali; Marsh Jonathan P; Faber Kenneth J; Drosdowech Darren

来源：Journal of Shoulder and Elbow Surgery, 2015, 24(3): 468-473.

DOI：10.1016/j.jse.2014.08.015

• Reverse shoulder arthroplasty
• BIO-RSA
• scapular notching
• complications
• cuff tear arthropathy

Background: The purpose of this cohort study was to compare scapular notching rates, range of motion, and functional outcomes between patients who underwent a standard Grammont-style reverse shoulder arthroplasty (RSA) and patients who underwent bony increased-offset reverse shoulder arthroplasty (BIO-RSA) at a minimum of 2 years' follow-up. We hypothesized that the BIO-RSA cohort would have lower notching rates and improved rotational range of motion; however, validated outcome scores between cohorts would be no different.
Methods: A comparative cohort study was designed after a sample size calculation. A total of 40 patients were studied with 20 in each cohort (RSA vs BIO-RSA). All patients underwent an interview and physical examination. Outcomes included range of motion; shoulder strength; Disabilities of the Arm, Shoulder and Hand (DASH) score; American Shoulder and Elbow Surgeons score; Simple Shoulder Test score; Constant score; and Global Rating of Change scale score. Radiographs were obtained for all patients and examined for scapular notching.
Results: When we compared demographic characteristics between the standard RSA and BIO-RSA cohorts, including age, sex, and follow-up duration, there were no significant differences between groups (P > .05). In addition, there were no significant differences between cohorts when we compared forward elevation (P=.418); external rotation (P =.999); internal rotation (P=.071); strength (P >.376); Disabilities of the Arm, Shoulder and Hand score (P=.229); American Shoulder and Elbow Surgeons score (P=.579); Simple Shoulder Test score (P=.522); Constant score (P=.917); or Global Rating of Change scale score (P=.167). The frequency of scapular notching, however, was significantly higher (P=.022) in the RSA cohort than in the BIO-RSA cohort: 75% versus 40%.
Conclusions: Although the scapular notching rate was significantly higher in the standard RSA group, no other outcome measures were statistically different, including range of motion, strength, and validated outcome scores.

• 出版日期2015-3