Tennis elbow: pain on the outside of the elbow

Tennis elbow is pain on the outside of the elbow, felt when gripping, lifting, turning a door handle or shaking hands. Fewer than one in ten cases involve tennis. Most involve a keyboard, a toolbox, a garden or a baby.

The proper name is lateral epicondylalgia, and the change from the older “epicondylitis” reflects a change in what we understand to be going on.

What is happening in the tendon

The muscles that extend the wrist and fingers share a common tendon attaching to the bony point on the outside of the elbow. Tennis elbow is a problem in that tendon, most often in the part belonging to extensor carpi radialis brevis.

It was long assumed to be inflammation. Tissue samples tell a different story: disorganised collagen, immature blood vessel growth and an absence of inflammatory cells. It is a failed healing response in a tendon that has been loaded beyond its capacity to adapt.

There is also a pain-system component. Long-standing cases often show changes in how the nervous system processes signals from the area, which is part of why the pain can seem out of proportion to what is visible.

Why the distinction matters

If it were inflammation, anti-inflammatories, ice and rest would resolve it. They do not. They manage symptoms for a few weeks and the problem returns as soon as the load does.

What changes a tendon is load, applied progressively. That is the treatment, and everything else is support for it.

What causes it

• A change in gripping load — new tools, a new job, a renovation, a new baby being lifted forty times a day
• Repetitive wrist extension under load — most manual trades, and some desk setups
• Poor grip strength relative to demand
• Neck and shoulder contributions — irritation of the cervical spine can refer to and sensitise the lateral elbow, which is why an assessment includes the neck even when the pain does not
• Age — most common between 35 and 55

What the evidence supports

Progressive loading. Isometric holds early where the tendon is very irritable, moving to heavy slow resistance wrist extension work. Consistently, over months. This is the intervention with the best evidence and the one most often abandoned early.

Load modification. Not stopping — reducing. A larger-diameter grip on tools, changing the mouse, spreading heavy tasks across a week, and lifting with the palm up rather than palm down all reduce the demand on the tendon while capacity rebuilds.

Manual therapy and dry needling. Useful for reducing pain enough to load properly. Mobilisation with movement techniques applied at the elbow have reasonable short-term evidence. On their own they do not resolve it.

A counterforce brace. The strap worn just below the elbow. It reduces symptoms in some people and does nothing in others, and it is cheap enough to be worth trying. It is a symptom aid, not a treatment.

Assessing the neck. Where cervical involvement is contributing, treating the elbow alone tends to produce partial and temporary results.

What the evidence does not support

Corticosteroid injection. This is the important one. Injection produces good relief at six weeks — and by twelve months, outcomes are significantly worse than doing nothing, with higher recurrence rates. It is still offered, and it should be a considered last resort rather than an early step.

Complete rest. Six weeks in a sling returns you to the same load with a weaker tendon.

Passive treatment alone. Ultrasound, laser and massage with no loading programme attached.

How long it takes

Six months is a fair expectation for a well-established case, and most resolve within a year with appropriate management. Cases picked up in the first few weeks often settle considerably faster, which is the argument for not waiting to see whether it goes away.

When it is something else

• Radial tunnel syndrome — pain slightly further down the forearm, more of an ache than a sharp pain, without the classic tenderness on the bony point
• Referred pain from the neck — often accompanied by neck stiffness or symptoms elsewhere in the arm
• Posterolateral elbow instability — usually following a dislocation or injection history
• Joint pathology — clicking, locking or loss of range points at the joint rather than the tendon

Pain that does not localise to that specific bony point, or comes with numbness and tingling, is worth having assessed rather than treated as tennis elbow.