Reverse total shoulder arthroplasty pain and function: new perspectives from a 10-year multicenter study at the 7-year follow-up.

BACKGROUND

Reverse total shoulder arthroplasty (RTSA) can decrease shoulder pain and improve function. However, results reportedly deteriorate as patients approach mid-term follow-up and little is known about how this impacts physical health-related quality of life (PHRQOL) and mental health-related quality of life (MHRQOL). The study hypothesis was that shoulder function, pain, and medication use for pain would influence PHRQOL and MHRQOL.

METHODS

This prospective cohort study involving subjects from 6 orthopedic clinics and 12 fellowship-trained surgeons evaluated the influence of RTSA on PHRQOL, MHRQOL, shoulder function, pain, instability, and medication use over the initial 7 years of a 10-year study, and device survivorship and revision rates. Clinical examination, the American Shoulder and Elbow Surgeons (ASES) score, Short Form (SF)-12 PHRQOL and MHRQOL assessments, the single assessment numeric shoulder function evaluation (SANE), visual analog scale (VAS) shoulder pain and instability scores, shoulder pain, medication use for pain, surgery satisfaction, survivorship and revision rate data were collected pre-RTSA, and at 6-week, 6-month, 1-year, 2-year, 3-year, 5-year, and 7-year follow-ups.

RESULTS

Two hundred participants (108 female) of 69 ± 8.3 years of age, with gross rotator cuff deficiency (poor tissue quality or impaired dynamic stability) (n = 92), glenohumeral joint osteoarthritis (n = 88), failed primary total shoulder arthroplasty (n = 8), non-united humeral head fracture (n = 6) or 3-4 section comminuted humeral head fracture (n = 6) underwent pre-RTSA evaluation. Device survivorship was 94%. Friedman two-way ANOVA and Wilcoxon test pairwise comparisons revealed that compared to pre-RTSA, median active shoulder flexion (+ 25°) and external rotation (+ 10°) mobility improved by 6 months (p < 0.0001) and remained improved. Shoulder flexion (+ 1 grade), abduction, external rotation (+ 0.5 grade), and internal rotation strength (+ 1 grade) also improved by 6 months (p < 0.0001) and remained improved. ASES (+ 26.8), SANE (+ 17.5) and VAS pain (- 5.7) scores improved by 6 weeks (p < 0.0001) and remained improved, as medication use for shoulder pain decreased (- 24.6%) (p < 0.0001). SF-12 PHRQOL scores improved by 6 months (+ 11.5) and remained improved (p < 0.0001). Significant Spearman Rho correlations were observed between shoulder function (ASES or SANE) and SF-12 PHRQOL (r ≥ 0.52) and MHRQOL (r ≥ 0.20) scores (p < 0.0001) supporting the relationship between shoulder function and quality of life. Trend analysis revealed changing shoulder function, pain, and PHRQOL relationships between 2 and 3 years, and 5 and 7 years post-RTSA (Chi-Square, p < 0.05).

CONCLUSION

Excellent device survival and good-to-excellent perceived shoulder function, and PHRQOL improvements were observed. Secondary objectives of improved shoulder mobility, strength, pain and instability were also achieved. In contrast to previous reports, subjects did not display shoulder mobility or perceived function deterioration by the 7-year follow-up. Following chronic pain relief at 6 weeks post-RTSA, subjects appear to balance PHRQOL and shoulder pain relationships at the 6-month and 1-year post-RTSA follow-ups. Careful evaluation at this time may help patients with higher pain levels and lower function expectations reverse these trends, or patients with lower pain levels and higher function expectations to optimize RTSA use and longevity.