title: Topical glyceryl trinitrate application in the treatment of chronic supraspinatus tendinopathy: a randomized, double-blinded, placebo-controlled clinical trial.
abstract: BACKGROUND
  Topical glyceryl trinitrate therapy has previously demonstrated short-term pain reduction in patients with supraspinatus tendinopathy.
  
  
  OBJECTIVE
  Topical glyceryl trinitrate improves outcome measures in patients with supraspinatus tendinopathy.
  
  
  METHODS
  Randomized controlled clinical trial; Level of evidence, 1.
  
  
  METHODS
  Fifty-three patients (57 shoulders) were recruited, and the authors completed a prospective, randomized, double-blinded, placebo-controlled clinical trial of continuous topical glyceryl trinitrate treatment (1.25 mg/24-h glyceryl trinitrate).
  
  
  RESULTS
  The glyceryl trinitrate group had significantly reduced shoulder pain with activity, at night, and at rest at week 24 (P = .03); reduced internal rotation impingement at week 24 (P = .02); increased range of motion in abduction and internal rotation at week 24 (P = .04); and increased force at weeks 12 and 24 with supraspinatus muscle testing (P = .001), external rotation (P = .04), internal rotation (P = .01), adduction (P = .04), and subscapularis pushoff (P = .01). Forty-six percent of patients on glyceryl trinitrate patches were asymptomatic with activities of daily living at 6 months compared with 24% of patients with tendon rehabilitation alone (P = .007, chi(2) analysis). Mean effect size for all outcome measures was 0.26.
  
  
  CONCLUSIONS
  Topical glyceryl trinitrate treatment significantly improved pain scores, range of motion, internal rotation impingement, muscular force, and patient outcomes in patients with supraspinatus tendinopathy. Topical glyceryl trinitrate should be included as part of nonsurgical management of chronic tendinopathies.
authors.affiliation: Orthopaedic Research Institute, Research and Education Centre, St George Hospital, 2nd Floor, 4 South Street, Kogarah, Sydney, 2217 Australia. pao_26@hotmail.com
authors.forename: Justin A
authors.initials: JA
authors.lastname: Paoloni
authors.forename: Richard C
authors.initials: RC
authors.lastname: Appleyard
authors.forename: Janis
authors.initials: J
authors.lastname: Nelson
authors.forename: George A C
authors.initials: GA
authors.lastname: Murrell
mesh_terms: D000287:Administration, Topical; D000328:Adult; D000368:Aged; D002908:Chronic Disease; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D005996:Nitroglycerin / Q000008:administration & dosage* / Q000009:adverse effects / Q000627:therapeutic use; D010146:Pain / Q000188:drug therapy*; D010919:Placebos; D012782:Shoulder; D052256:Tendinopathy / Q000503:physiopathology* / Q000534:rehabilitation; D014665:Vasodilator Agents / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use
chemical_list: D010919:Placebos; D014665:Vasodilator Agents; D005996:Nitroglycerin