We discovered that a heightened expression of HMGCR in muscle tissue correlates with a diminished risk of developing rotator cuff syndrome (OR = 0.88, [95% CI, 0.76–0.99], p = 0.03) However, our findings indicated no significant association between the levels of HMGCR and PCSK9 expression in whole blood, as well as PCSK9 expression in visceral fat, and the risk of rotator cuff syndrome. This evidence concerns the gene PCSK9 and rotator cuff syndrome.