This summary of a Cochrane review presents what we know from research about the effect of glyceryl trinitrate patches on rotator cuff disease (RCD).
Pain
- glyceryl trinitrate patches (5 mg/day) may improve pain slightly.
- the effects of glyceryl trinitrate patches (1.25 mg/day) along with rehabilitation instruction (such as exercise) and glyceryl trinitrate patches (5 mg/day) compared to injection with corticosteroid and painkillers on pain were not reported by the studies included in the review.
Symptoms of RCD
- it is uncertain whether glyceryl trinitrate patches (5 mg/day) eliminate symptoms of RCD because of the very low quality of the evidence.
- glyceryl trinitrate (1.25 mg/day) along with rehabilitation instruction (such as exercise) may be no more likely to eliminate symptoms than rehabilitation instruction alone.
- the effect of glyceryl trinitrate patches (5 mg/day) compared to injection with corticosteroid and painkillers could not be determined in this review.
Physical Function
- improvement in peoples’ physical function was not measured by any of the studies included in the review.
Side Effects
- it is uncertain whether topical glyceryl trinitrate (5 mg/day) has side effects such as headache because of the very low quality of the evidence.
- glyceryl trinitrate (1.25 mg/day) along with rehabilitation instruction (such as exercise) may be no more likely to cause headache or rash than rehabilitation instruction alone.
What is rotator cuff disease and what is glyceryl trinitrate?
The rotator cuff is a group of tendons that surrounds the shoulder joint. In some people, the muscles and tendons pinch when they move their shoulder over and over again. The pinching can cause the rotator cuff to swell, break down and it may tear away from the bone - this is called rotator cuff disease or tendonitis. In a lot of people, it is a normal part of ageing and they may not have symptoms. But many people with rotator cuff disease do have pain in their shoulder at some time that may not go away on its own.
Topical glyceryl trinitrate (also called nitroglycerin or nitroglycerine) has been used to treat chest pain for many years, and has been proposed as a promising treatment for muscle and tendon injuries. For treatment of soft tissue conditions glyceryl trinitrate is delivered topically, through the skin, using medicated patches.
There is some evidence from one study at high risk of bias that topical glyceryl trinitrate is more effective than placebo for rotator cuff disease among patients with acute symptoms (< seven-days duration), but there is insufficient evidence to be certain about their longer-term effects. Headache was a common side effect in one trial and any benefits of treatment need to be balanced against the risk of headache. Further high quality research is needed to determine the effectiveness and safety of this new therapy.
Rotator cuff disease is a common cause of shoulder pain. Topical glyceryl trinitrate is a possible new treatment.
To determine the effectiveness and safety of topical glyceryl trinitrate for rotator cuff disease.
We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, CINAHL, SPORTDiscus, PEDro, the Australian Clinical Trials Registry, Current Controlled Trials (to October 2007) and the references and citations of included studies.
We included randomised controlled trials and controlled clinical trials of people with rotator cuff disease who received topical glyceryl trinitrate, alone or in combination, compared to placebo or active therapy.
Two authors independently assessed risk of bias and extracted data.
Three small studies, one at moderate risk of bias and two at high risk of bias, were included. Meta-analysis was precluded due to different interventions and outcome measures. Study participants also had differing durations of symptoms and data for pain and function could only be extracted from one study. One placebo-controlled trial (20 participants) tested 5 mg glyceryl trinitrate patches, used daily for three days, among participants with 'acute supraspinatus tendinitis' of less than seven days duration. Treatment resulted in reduced pain intensity (adjusted MD -3.50, 95% CI -3.96 to -3.04). Function was not measured. One trial (53 participants) compared one quarter of a 5 mg glyceryl trinitrate patch used daily for up to 24 weeks combined with rehabilitation to placebo patches and rehabilitation among participants with 'supraspinatus tendinopathy' for longer than six months. A third trial (48 participants) tested 5 mg glyceryl trinitrate patches, used daily for three days, compared to corticosteroid injection among participants with 'rotator cuff tendinitis' of less than six-weeks duration. Fifteen out of 24 participants in the glyceryl trinitrate treatment reported headache (RR 0.11, 95% CI 0.01 to 1.96).