title: Is intra-articular magnesium effective for postoperative analgesia in arthroscopic shoulder surgery?
abstract: BACKGROUND
  Various medications are used intra-articularly for postoperative pain reduction after arthroscopic shoulder surgery. Magnesium, a N-methyl-D-aspartate receptor antagonist, may be effective for reduction of both postoperative pain scores and analgesic requirements.
  
  
  METHODS
  A total of 67 patients undergoing arthroscopic shoulder surgery were divided randomly into two groups to receive intra-articular injections of either 10 mL magnesium sulphate (100 mg⁄mL; group M, n=34) or 10 mL of normal saline (group C, n=33). The analgesic effect was estimated using a visual analogue scale 1 h, 2 h, 6 h, 8 h, 12 h, 18 h and 24 h after operation. Postoperative analgesia was maintained by intra-articular morphine (0.01%, 10 mg) + bupivacaine (0.5%, 100 mL) patient-controlled analgesia device as a 1 mL infusion with a 1 mL bolus dose and 15 min lock-out time; for visual analogue scale scores >5, intramuscular diclofenac sodium 75 mg was administered as needed during the study period (maximum two times).
  
  
  RESULTS
  Intra-articular magnesium resulted in a significant reduction in pain scores in group M compared with group C 1 h, 2 h, 6 h, 8 h and 12 h after the end of surgery, respectively, at rest and with passive motion. Total diclofenac consumption and intra-articular morphine + bupivacaine consumption were significantly lower in group M. Postoperative serum magnesium levels were significantly higher in group M, but were within the normal range.
  
  
  CONCLUSIONS
  Magnesium causes a reduction in postoperative pain in comparison to saline when administered intra-articularly after arthroscopic shoulder surgery, and has no serious side effects.
authors.forename: Tuba Berra
authors.initials: TB
authors.lastname: Saritas
authors.forename: Hale
authors.initials: H
authors.lastname: Borazan
authors.forename: Selmin
authors.initials: S
authors.lastname: Okesli
authors.forename: Mustafa
authors.initials: M
authors.lastname: Yel
authors.forename: Şeref
authors.initials: Ş
authors.lastname: Otelcioglu
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000700:Analgesics / Q000008:administration & dosage*; D001182:Arthroscopy; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D007270:Injections, Intra-Articular; D008274:Magnesium / Q000008:administration & dosage*; D008297:Male; D008875:Middle Aged; D059408:Pain Management / Q000379:methods*; D010147:Pain Measurement; D010149:Postoperative Pain / Q000188:drug therapy*; D012782:Shoulder / Q000601:surgery; D055815:Young Adult
chemical_list: D000700:Analgesics; D008274:Magnesium