Low serum vitamin B12 levels are associated with degenerative rotator cuff tear

Background Vitamin B.sub.12 (Vit B.sub.12) deficiency results in elevated homocysteine levels and interference with collagen cross-linking, which may affect tendon integrity. The purpose of this study was to investigate whether serum Vit B.sub.12 levels were correlated with degenerative rotator cuff (RC) tear. Methods Eighty-seven consecutive patients with or without degenerative RC tear were enrolled as study participants. Possible risk factors (age, sex, medical history, bone mineral density, and serum chemistries including glucose, magnesium, calcium, phosphorus, zinc, homocysteine, Vitamin D, Vit B.sub.12, homocysteine, and folate) were assessed. Significant variables were selected based on the results of univariate analyses, and a logistic regression model (backward elimination) was constructed to predict the presence of degenerative RC tear. Results In the univariate analysis, the group of patients with degenerative RC tear had a mean concentration of 528.4 pg/mL Vit B.sub.12, which was significantly lower than the healthy control group (627.1 pg/mL). Logistic regression analysis using Vit B.sub.12 as an independent variable revealed that Vit B.sub.12 concentrations were significantly correlated with degenerative RC tear (p = 0.044). However, Vit B.sub.12 levels were not associated with tear size. Conclusion Low serum levels of Vit B.sub.12 were independently related to degenerative RC tear. Further investigations are warranted to determine if Vit B.sub.12 supplementation can decrease the risk of this condition. Keywords: Vitamin B.sub.12, Rotator cuff, Degenerative, Tear