Tennis Elbow – Why Corticosteroid Is Rarely the Answer

Tennis elbow affects far more people than tennis players, and the name is misleading in more ways than one. The suffix '-itis' suggests inflammation, but what we find in the tissue is something else: a tendon disorder with disrupted tissue quality. That has direct consequences for which treatment actually works.

Not an inflammation, but a tendon disorder

Tennis elbow arises at the tendon insertion of the wrist extensor muscles on the outside of the elbow. When the tissue is examined, classic inflammatory cells are rarely found. What is seen instead is disorganised collagen fibres, ingrowth of new blood vessels and nerves, and a tendon whose structure has gradually changed as a result of sustained overload.

This is why the field has moved away from 'epicondylitis' in favour of tendinopathy or lateral epicondylalgia. The shift isn't mere semantics – it explains why anti-inflammatory treatment gives short-term relief but doesn't resolve the underlying problem.

What the JAMA corticosteroid trial showed

A randomised trial published in JAMA in 2013 followed patients with tennis elbow for one year, comparing corticosteroid injection, physiotherapy, both, and placebo.

The result was striking: the corticosteroid group had faster relief in the first weeks, but clearly worse outcomes after one year. Complete recovery was achieved in 83% of the corticosteroid group versus 96% in the placebo group, and recurrence occurred in as many as 54% after corticosteroid versus 12% after placebo.

The trial also showed that adding physiotherapy to the corticosteroid injection did not offset this effect. Corticosteroid is therefore not merely 'unnecessary' in tennis elbow – it appears capable of interfering with the tendon's natural healing.

Exercise is the primary treatment

Tendons adapt to load. The best-documented treatment for tennis elbow is therefore progressive strength training of the forearm extensor muscles, often combined with work on the shoulder and neck, since weakness further up the chain frequently contributes to overload down at the elbow.

The key is dosage. The load must be high enough to provide the tendon with an adaptive stimulus, but low enough that symptoms don't escalate. Some pain during and after training is acceptable as long as it settles within 24 hours and doesn't worsen week on week. This requires follow-up and adjustment – not a static exercise sheet.

Where PRP comes in

PRP (platelet-rich plasma) is produced by drawing a small amount of your own blood, centrifuging it, and injecting the concentrated platelet fraction precisely into the affected tendon tissue. The platelets contain growth factors intended to stimulate the tissue's own repair process.

A systematic review and meta-analysis in the American Journal of Sports Medicine from 2024 compared PRP with corticosteroid in tennis elbow. The conclusion was that corticosteroid gives the best short-term effect, while PRP produces better function and pain relief in the long term. The time profile is essentially the opposite of corticosteroid.

My clinical view: PRP is not a first choice, and must never replace the exercise. But for those who have followed a well-structured training programme over sufficient time without progressing, PRP is a genuine option – and a far more sensible choice than repeated corticosteroid injections, which over time can weaken the tendon tissue further.

Why ultrasound and clinical examination belong together

Pain on the outside of the elbow isn't always tennis elbow. Entrapment of the deep radial nerve, problems in the elbow joint itself, or referred pain from the neck and shoulder can produce a similar picture. A structured clinical examination with resisted tests and palpation usually distinguishes these from one another.

Ultrasound lets me see the tendon insertion directly: thickening, breakdown of fibre structure, calcifications, vascular ingrowth and any partial tears. It confirms the diagnosis, provides information about how pronounced the tendon disorder is – and therefore how long you should realistically expect it to take – and guides any injection precisely into the right tissue.

Sources

1. Coombes BK, Bisset L, Brooks P, Khan A, Vicenzino B. "Effect of Corticosteroid Injection, Physiotherapy, or Both on Clinical Outcomes in Patients With Unilateral Lateral Epicondylalgia: A Randomized Controlled Trial." JAMA 2013;309(5):461–469.
2. Xu Y, Li T, Wang L, Yao L, Li J, Tang X. "Platelet-Rich Plasma Has Better Results for Long-term Functional Improvement and Pain Relief for Lateral Epicondylitis: A Systematic Review and Meta-analysis of Randomized Controlled Trials." American Journal of Sports Medicine 2024;52(10):2646–2656.