title: Efficacy of methylsulfonylmethane (MSM) in osteoarthritis pain of the knee: a pilot clinical trial.
abstract: OBJECTIVE
  Osteoarthritis (OA) is the most common form of arthritis and the second most common cause of long-term disability among middle-aged and older adults in the United States. Methylsulfonylmethane (MSM) is a popular dietary supplement used as a single agent and in combination with other nutrients, and purported to be beneficial for arthritis. However, there is paucity of evidence to support the use of MSM.
  
  
  METHODS
  A randomized, double-blind, placebo-controlled trial was conducted. Fifty men and women, 40-76 years of age with knee OA pain were enrolled in an outpatient medical center. Intervention was MSM 3g or placebo twice a day for 12 weeks (6g/day total). Outcomes included the Western Ontario and McMaster University Osteoarthritis Index visual analogue scale (WOMAC), patient and physician global assessments (disease status, response to therapy), and SF-36 (overall health-related quality of life).
  
  
  RESULTS
  Compared to placebo, MSM produced significant decreases in WOMAC pain and physical function impairment (P<0.05). No notable changes were found in WOMAC stiffness and aggregated total symptoms scores. MSM also produced improvement in performing activities of daily living when compared to placebo on the SF-36 evaluation (P<0.05).
  
  
  CONCLUSIONS
  MSM (3g twice a day) improved symptoms of pain and physical function during the short intervention without major adverse events. The benefits and safety of MSM in managing OA and long-term use cannot be confirmed from this pilot trial, but its potential clinical application is examined. Underlying mechanisms of action and need for further investigation of MSM are discussed.
authors.affiliation: Southwest College Research Institute, Southwest College of Naturopathic Medicine and Health Sciences, Tempe, AZ 85282, USA. l.kim@scnm.edu
authors.forename: L S
authors.initials: LS
authors.lastname: Kim
authors.forename: L J
authors.initials: LJ
authors.lastname: Axelrod
authors.forename: P
authors.initials: P
authors.lastname: Howard
authors.forename: N
authors.initials: N
authors.lastname: Buratovich
authors.forename: R F
authors.initials: RF
authors.lastname: Waters
mesh_terms: D000328:Adult; D000368:Aged; D000700:Analgesics; D019587:Dietary Supplements / Q000009:adverse effects; D004121:Dimethyl Sulfoxide; D004311:Double-Blind Method; D004334:Drug Administration Schedule; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000150:complications / Q000188:drug therapy* / Q000503:physiopathology; D010146:Pain / Q000188:drug therapy* / Q000209:etiology; D010865:Pilot Projects; D012720:Severity of Illness Index; D013450:Sulfones / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D016896:Treatment Outcome
chemical_list: D000700:Analgesics; D013450:Sulfones; C025910:dimethyl sulfone; D004121:Dimethyl Sulfoxide