ABSTRACT
INTRODUCTION: The incidence of reverse shoulder arthroplasty (RTSA) in the United States has increased. Patients under 60 years old with failed rotator cuff repairs or degenerative joint disease with glenoid deformity may be candidates for RTSA and contribute to this increase. The single assessment numeric evaluation (SANE) score is a reliable post-operative scoring technique when compared with other post-operative measures. This study aimed to compare the effect of age on the likelihood of reaching clinically significant SANE scores following RTSA. METHODS: A multicenter retrospective review was performed with a consecutive series of RTSA from December 2015 to September 2021. Patients were stratified into groups based on their age at the time of operation: (1) less than 60 years old, (2) 60-69 years old, (3) 70-79 years old, and (3) greater than 80 years old. The proportions of patients in all cohorts reaching and surpassing clinically significant thresholds at each visit were determined. Likelihood ratios were determined for each age cohort to compare the likelihood of reaching clinically significant SANE scores. RESULTS: A total of 292 of 885 (33%) patients had completed survey data over two years and were included in the study. The 70-79-year-old group was 3.152 (p=.035) times more likely to achieve minimal clinically important difference (MCID) and 2.125 (p=.048) times more likely to achieve patient-acceptable symptomatic state (PASS) compared with patients <60 years old. The cohort who was 80+ years old was also 4.867 (p=.045) times more likely to achieve MCID compared to the <60-year-old cohort. The <60 cohort had the lowest proportion of all patient cohorts achieving MCID. CONCLUSION: A lower proportion of patients younger than 60 years old undergoing RTSA achieved clinically significant post-operative SANE scores. The 70-79-year-old age group was more likely to reach MCID and PASS, and the patients who were 80+ years old were more likely to reach MCID compared to patients younger than 60 years old.
ABSTRACT
BACKGROUND: We aimed to biomechanically evaluate the distal pronator quadratus and compare two locations of distal transection on the strength of the subsequent repair. METHODS: Eighteen fresh-frozen cadaveric specimens were dissected to the pronator quadratus muscle. Specimens were randomly allocated for transection of the pronator quadratus at the myotendinous junction (red group) or parallel to the myotendinous junction at the midsection of the distal tendinous zone (white group). For both groups, repair of the muscle was performed using two figure-of-8 sutures. The radius and ulna were positioned in 90° of wrist extension. The proximal muscular pronator quadratus was fixed in a cryo-clamp. Load-to-failure testing of the repair was performed at 1 mm/s with maximum amount of force applied to the pronator quadratus recorded for each specimen. FINDINGS: The pronator quadratus had a mean width, height, and area of 31.41 ± 5.74 mm, 53.79 ± 7.46 mm, and 1604.27 ± 429.20 mm2 respectively. The pronator quadratus distal tendinous zone had a mean width, height, and area of 29.71 ± 5.83 mm, 12.22 ± 2.79 mm, 282.94 ± 148.30 mm2 respectively. There was no significant difference between the two groups for pronator quadratus height, width, total area, or tendinous zone height, width, or total area. The average load to failure for the white group was significantly higher than that of the red group (29.46 ± 4.24 N vs. 13.78 N ± 6.66 N). INTERPRETATION: Incision and repair of the pronator quadratus in the distal tendinous region is stronger than incision and repair at the red myotendinous junction of the distal PQ.
