title: Low Serum Vitamin D Is Not Correlated With the Severity of a Rotator Cuff Tear or Retear After Arthroscopic Repair.
abstract: BACKGROUND
  Despite the essential role of vitamin D in muscle function, the prevalence of vitamin D deficiency has been reported to be very high. Recently, low vitamin D level was found to correlate with fatty degeneration of the rotator cuff tendon in humans and to negatively affect early healing at the rotator cuff repair site in an animal study. However, the effects of vitamin D level on severity of rotator cuff tear and healing after surgical repair have not been documented.
  
  
  OBJECTIVE
  To evaluate (1) the prevalence of vitamin D deficiency among patients who underwent arthroscopic repair for a full-thickness rotator cuff tear, (2) the relationship of vitamin D level with severity of the rotator cuff tear, and (3) surgical outcomes after repair.
  
  
  METHODS
  Cohort study; Level of evidence, 2.
  
  
  METHODS
  A consecutive series of 91 patients (age, 50-65 years) who underwent arthroscopic rotator cuff repair for full-thickness, small-sized to massive tears were evaluated. Preoperative serum vitamin D levels (25-hydroxyvitamin) were analyzed to detect correlations with the features of a preoperative rotator cuff tear as well as postoperative structural and functional outcomes. All patients were followed clinically for a minimum of 1 year.
  
  
  RESULTS
  Preoperative vitamin D levels were deficient (<20 ng/mL) in 80 subjects (88%), insufficient (20-30 ng/mL) in 8 subjects (9%), and normal (>30 ng/mL) in 3 subjects (3%). No correlation was found between preoperative tear size (P = .23), extent of retraction (P = .60), degree of fatty infiltration of each cuff muscle (P > .50 each), or the global fatty infiltration index (P = .32). Similarly, no correlations were detected between vitamin D level and postoperative Sugaya type (P = .66) or any of the functional outcome scores (P > .50 each).
  
  
  CONCLUSIONS
  Low serum vitamin D level was not related to tear size, extent of retraction, or the degree of fatty infiltration in cuff muscles. It also had no significant relationships with postoperative structural integrity and functional outcomes after arthroscopic repair. The results suggest that low serum vitamin D level is not a significant risk factor for the severity of rotator cuff tear or poor healing after repair.
authors: Department of Orthopaedic Surgery, Severance Hospital, Yonsei Medical Center, Yonsei University College of Medicine, Seoul, Republic of Korea.
authors: Keun Jung
authors: KJ
authors: Ryu
authors: Department of Orthopaedic Surgery, CHA Bundang Medical Center, CHA University, Seongnam-si, Kyeonggi-do, Republic of Korea.
authors: Bang Hyun
authors: BH
authors: Kim
authors: Department of Orthopaedic Surgery, CHA Bundang Medical Center, CHA University, Seongnam-si, Kyeonggi-do, Republic of Korea.
authors: Yohan
authors: Y
authors: Lee
authors: Department of Orthopaedic Surgery, CHA Gumi Medical Center, School of Medicine, CHA University, Seongnam-si, Kyeonggi-do, Republic of Korea.
authors: Jinmyoung
authors: J
authors: Dan
authors: Department of Orthopaedic Surgery, CHA Bundang Medical Center, CHA University, Seongnam-si, Kyeonggi-do, Republic of Korea drjkim@cha.ac.kr.
authors: Jae Hwa
authors: JH
authors: Kim
mesh_terms: D000368:Aged; D001182:Arthroscopy / Q000379:methods*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011184:Postoperative Period; D017006:Rotator Cuff / Q000473:pathology / Q000601:surgery*; D013708:Tendon Injuries / Q000601:surgery; D016896:Treatment Outcome; D014807:Vitamin D / Q000097:blood*; D014808:Vitamin D Deficiency / Q000453:epidemiology*
chemical_list: D014807:Vitamin D
keywords: 25-hydroxyvitamin; calcifediol; retear; rotator cuff; vitamin D