title: Topical glyceryl trinitrate treatment of chronic patellar tendinopathy: a randomised, double-blind, placebo-controlled clinical trial.
abstract: OBJECTIVE
  To assess if continuous topical glyceryl trinitrate (GTN) treatment improves outcome in patients with chronic patellar tendinopathy when compared with eccentric training alone.
  
  
  METHODS
  Randomised double-blind, placebo-controlled clinical trial comparing a 12-week programme of using a GTN or placebo patch in combination with eccentric squats on a decline board. Measurements were performed at baseline, 6, 12 and 24 weeks. Primary outcome measure was the Victorian Institute of Sports Assessment-Patella (VISA-P) questionnaire. Secondary outcome measures were patient satisfaction and pain scores during sports. Generalised estimated equation was used to analyse the treatment, time and treatment×time effect. Analyses were performed following the intention-to-treat principle.
  
  
  RESULTS
  VISA-P scores for both groups improved over the study period to 75.0±16.2 and 80.7±22.1 at 24 weeks. Results showed a significant effect for time (p<0.01) but no effect for treatment×time (p=0.80). Mean Visual Analogue Scores pain scores during sports for both groups increased over the study period to 6.6±3 and 7.8±3.1. Results showed a significant effect for time (p<0.01) but no effect for treatment×time (p=0.38). Patient satisfaction showed no difference between GTN and placebo groups (p=0.25) after 24 weeks, but did show a significant difference over time (p=0.01). Three patients in the GTN group reported some rash.
  
  
  CONCLUSIONS
  It seems that continuous topical GTN treatment in addition to an eccentric exercise programme does not improve clinical outcome compared to placebo patches and an eccentric exercise programme in patients with chronic patellar tendinopathy.
authors.affiliation: Department of Steunebrink Sportsmedicine, Eelde, The Netherlands. mirjamsteunebrink@gmail.com
authors.forename: Mirjam
authors.initials: M
authors.lastname: Steunebrink
authors.forename: Johannes
authors.initials: J
authors.lastname: Zwerver
authors.forename: Ruben
authors.initials: R
authors.lastname: Brandsema
authors.forename: Petra
authors.initials: P
authors.lastname: Groenenboom
authors.forename: Inge
authors.initials: I
authors.lastname: van den Akker-Scheek
authors.forename: Adam
authors.initials: A
authors.lastname: Weir
mesh_terms: D000279:Administration, Cutaneous; D000293:Adolescent; D000328:Adult; D000700:Analgesics / Q000008:administration & dosage*; D059350:Chronic Pain / Q000517:prevention & control; D004311:Double-Blind Method; D006801:Humans; D059352:Musculoskeletal Pain / Q000517:prevention & control*; D005996:Nitroglycerin / Q000008:administration & dosage*; D017847:Patellar Ligament; D017060:Patient Satisfaction; D052256:Tendinopathy / Q000628:therapy*; D057968:Transdermal Patch; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D000700:Analgesics; D005996:Nitroglycerin