Cancienne JM, et al. - Using a private-payer national insurance database, a total of 982 subjects were studied to investigate the relationship between perioperative serum 25-hydroxyvitamin D levels and failure of arthroscopic rotator cuff repair (RCR) needing revision surgery. Authors observed a significantly higher rate of revision rotator cuff surgery in serum 25-hydroxyvitamin D–deficient group. They noticed an absolute risk reduction of 2.2% (revision surgery after primary arthroscopic RCR) for 25-hydroxyvitamin D–deficient subjects.