Pearls of Wisdom: Tennis Elbow

Arnold is a 36-year-old man with refractory lateral epicondylitis of the right elbow. Which treatment might improve his symptoms?

A. Systemic vitamin D
B. Topical vitamin E
C. Topical nitroglycerin
D. Injectable botulinum toxin

What is the correct answer?

(Answer and discussion on next page)

Louis Kuritzky, MD, has been involved in medical education since the 1970s. Drawing upon years of clinical experience, he has crafted each year for almost 3 decades a collection of items that are often underappreciated by clinicians, yet important for patients. These “Pearls of Wisdom” often highlight studies that may not have gotten traction within the clinical community and/or may have been overlooked since their time of publishing, but warrant a second look.

Answer: Topical Nitroglycerin

Lateral epicondylitis, or “tennis elbow” as it is colloquially known, is a common problem that we would like to become more successful at treating. Unfortunately, many of the treatments we have used in the past have been inconsistently effective. We have tried ultrasonography, laser treatment, electrogalvanic stimulation, and corticosteroid injections—which are often associated with short-term improvement of symptoms for 2 to 6 weeks, but not in the long term. Currently, rest is recommended, as well as physical therapy involving stretching or strengthening exercises.

However, several studies have suggested the potential use of nitroglycerin.

The Research

A 2003 double-blind, randomized, placebo-controlled trial assigned 86 patients with lateral epicondylitis to either nitroglycerin transdermal patch (5 mg) or placebo patch. The patches were cut into quarters, with 1 quarter applied to the elbow every day for 6 months. Outcomes were measured using the Orthopaedic Research Institute Tennis Elbow Testing System score, levels of pain with activity, and epicondyle tenderness. All patients, regardless of which group they were assigned to, also underwent tendon rehabilitation with rest, a brace of the arm, and some stretching exercises to strengthen the elbow.

Some adverse events were reported in the nitroglycerin group, most commonly persistent headaches. While it is predictable that many patients applying significant amounts of nitroglycerin topically will get a headache, it is somewhat surprising in this case due to the relatively small dosage. Several patients developed contact dermatitis, and a single patient reported facial flushing and angiodysplasia.

Transdermal Nitroglycerin Adverse Effects

The small number of dropouts is encouraging, suggesting that most individuals will tolerate nitroglycerin well.

The Results

Patient-Rated Elbow Pain With Activity

As early as week 2, there was a statistically significant reduction in self-reported elbow pain. These results were persistent throughout the 24 weeks of the study, which is very encouraging, considering that other treatments such as corticosteroids have not shown favorable effects beyond 2 months.

Similar results were observed in reduction in pain and tenderness at the epicondyle, and participants using nitroglycerin also had better outcomes on the Orthopaedic Research Institute Tennis Elbow Testing System score.

Overall, 81% of patients using the nitroglycerin patch reported that they were asymptomatic in all of their daily activities, compared with 60% of those using the placebo. Why is the placebo rate so high? This can most likely be attributed to the physical therapy that all patients were also undergoing during the study.

Patient-Reported Outcomes

What’s the “Take-Home”?

Most individuals will tolerate nitroglycerin well, and I would even consider extrapolating from this data to use forms of nitroglycerin that might be better tolerated, such as compounded nitroglycerin ointment, 0.2%. Nitroglycerin can be compounded into whatever percentage paste/ointment we’d like—traditional nitroglycerine paste, as used for angina treatment, is 2%, but compounded nitroglycerine paste at 0.2% has been used successfully to treat other disorders.

Reference:

1. Paoloni JA, Appleyard RC, Nelson J, Murrell GAC. Topical nitric oxide application in the treatment of chronic extensor tendinosis at the elbow. Am J Sports Med. 2003;31(6):915-920.