What Is Tennis Elbow? Causes, Symptoms, and Treatment

Tennis elbow — medically known as lateral epicondylitis — is a painful overuse injury of the tendons on the outside of the elbow. It is caused by repetitive strain on the forearm muscles, leading to small tears in the tendon where it attaches to the lateral epicondyle. Despite the name, most people who develop it have never picked up a racket.

What Is the Lateral Epicondyle?

The lateral epicondyle is the bony prominence on the outer side of the elbow. Several forearm muscles responsible for extending the wrist and fingers attach here via a shared tendon. When those muscles are overworked through repetitive gripping or wrist extension, the tendon becomes irritated and develops micro-tears — that is tennis elbow.

Common Causes

Cause Category	Examples
Racket sports	Tennis (especially backhand technique), squash, badminton, padel
Occupational	Painting, plumbing, carpentry, butchery, typing
Everyday activities	Repeated lifting, using a screwdriver, prolonged mouse use

In tennis specifically, poor backhand technique — hitting with a bent wrist or using too much forearm — places excessive load on the lateral tendons. Racket factors such as string tension, grip size, and frame stiffness also play a role.

Symptoms

• Pain and tenderness on the outside of the elbow
• Weakness in the wrist and forearm
• Pain that worsens when gripping, lifting, or twisting the forearm (e.g., turning a door handle)
• Discomfort radiating down the forearm toward the wrist
• Stiffness when extending the arm fully

Symptoms typically develop gradually rather than from a single incident.

Diagnosis

A doctor or physiotherapist usually diagnoses tennis elbow through a physical examination — testing pain response when the wrist is extended against resistance. Imaging (ultrasound or MRI) is occasionally used to confirm tendon damage or rule out other conditions.

Treatment Options

Most cases respond well to conservative management:

1. Rest and activity modification: Reducing or stopping the movements that trigger pain.
2. Ice: Applying ice to the lateral elbow for short periods helps manage acute inflammation.
3. Physiotherapy: Eccentric strengthening exercises for the forearm extensors are the cornerstone of recovery.
4. Counterforce brace: A strap worn just below the elbow reduces load on the tendon during activity.
5. Anti-inflammatory medication: NSAIDs (e.g., ibuprofen) can provide short-term pain relief.
6. Corticosteroid injections: Offer temporary pain relief but may not improve long-term outcomes.
7. PRP therapy: Platelet-rich plasma injections are used in persistent cases to promote tendon healing.
8. Surgery: Reserved for cases that do not respond to months of conservative treatment.

Prevention in Tennis Players

• Use correct backhand technique — hit with a stable wrist, not a flicked forearm.
• Ensure grip size is appropriate (too small increases forearm muscle effort).
• Consider lower string tension, which reduces shock transmission.
• Build forearm strength gradually and include warm-up and cool-down routines.
• Avoid sudden increases in playing volume.

Tennis Elbow vs. Golfer’s Elbow

A common point of confusion:

Condition	Affected Side	Tendons Involved
Tennis elbow (lateral epicondylitis)	Outside of elbow	Wrist extensor tendons
Golfer’s elbow (medial epicondylitis)	Inside of elbow	Wrist flexor tendons

Both are overuse tendon injuries but affect opposite sides of the elbow and involve different muscle groups.

Quick summary: Tennis elbow is an overuse injury to the tendons on the outside of the elbow, most commonly caused by repetitive forearm and wrist movements. Treatment centers on rest, physiotherapy exercises, and activity modification. It affects far more non-tennis players than tennis players and is one of the most common arm injuries in adults.