Tennis elbow and golfer’s elbow are both caused by overuse of the forearm muscles, leading to damage where the tendons attach to the bony bumps on either side of your elbow. Despite their names, most people who develop these conditions have never picked up a racket or a golf club. Repetitive gripping, twisting, and lifting motions in everyday work and hobbies are far more common culprits.
The two conditions mirror each other. Tennis elbow (lateral epicondylitis) affects the outside of the elbow. Golfer’s elbow (medial epicondylitis) affects the inside. Both involve the same basic process: repeated stress on forearm tendons that outpaces the body’s ability to repair them.
The Tendons Involved
Your elbow has two bony bumps, one on each side, called epicondyles. Different groups of forearm muscles anchor to each one through tendons, and which bump gets overloaded determines which condition you develop.
In tennis elbow, the primary tendon involved is the one that connects a forearm muscle called the extensor carpi radialis brevis (ECRB) to the outer bump of the elbow. This muscle helps you extend and stabilize your wrist, something you do constantly when gripping, lifting, or twisting objects. The ECRB tendon is especially vulnerable because of its position: as the elbow bends and straightens, the muscle rubs against bony prominences, causing gradual wear over time.
In golfer’s elbow, the tendons on the inner side of the elbow are affected. These connect the muscles you use to flex your wrist, grip tightly, and rotate your forearm inward. Any activity that requires repeated bending, grasping, or twisting of the wrist can overload this area.
Overuse and Micro-Tears
The core cause of both conditions is repetitive stress. Every time you grip a tool, swing a racket, or turn a wrench, the tendons at your elbow absorb force. In small doses, this is fine. Your body repairs minor damage between activities. But when the same motion is repeated too often, too forcefully, or without enough recovery time, microscopic tears form in the tendon where it attaches to bone. These micro-tears accumulate faster than your body can heal them.
Three mechanical factors consistently raise the risk: high force demands on the hand and wrist, highly repetitive movements, and awkward or non-neutral wrist positions. When two or three of these factors combine, such as forceful gripping in an awkward posture, the risk climbs significantly.
Degeneration, Not Inflammation
For decades, both conditions were treated as inflammatory problems, which is why they still carry the “-itis” suffix (meaning inflammation). But research has shifted that understanding considerably. When scientists examine tissue samples from painful tendons, they consistently find areas of collagen degeneration, increased blood vessel growth, and tendon thickening, but a distinct lack of inflammatory cells.
This means the condition most people actually have is closer to tendinosis (chronic degeneration) than tendinitis (acute inflammation). The collagen fibers that make up the tendon break down and lose their organized structure. True inflammatory tendinitis does occur, but it’s rare and typically only present in the very earliest stages of injury. By the time most people seek help, the problem is degenerative. This distinction matters because treatments aimed purely at reducing inflammation, like ice and anti-inflammatory medications, may relieve symptoms without addressing the underlying tissue breakdown.
Activities That Cause Each Condition
The specific motions that trigger tennis elbow versus golfer’s elbow differ because different muscle groups are involved.
Tennis elbow is linked to activities that load the muscles on the back of the forearm, the ones that extend the wrist and fingers. Common causes include:
- Racket sports: Repeated backhand strokes, especially with poor technique or a too-heavy racket
- Manual trades: Plumbing, painting, carpentry, and any work involving repetitive use of hand tools
- Office and computer work: Prolonged mouse use with a non-neutral wrist position
- Kitchen work: Chopping, butchering, and repetitive knife use
- Assembly line tasks: Repeated gripping, turning, or lifting of parts
Golfer’s elbow is driven by activities that load the muscles on the palm side of the forearm, those responsible for wrist flexion and gripping. Common causes include:
- Golf: The lead arm during the downswing absorbs significant force through the inner elbow
- Throwing sports: Baseball pitching, javelin, and football passing
- Weight training: Curls, rows, and heavy gripping exercises
- Construction and trades: Hammering, turning screwdrivers, operating vibrating tools
- Climbing: Sustained grip on holds loads the inner forearm tendons heavily
Who Gets It and When
Both conditions are most common in people aged 40 and older. This makes sense because tendons naturally lose some of their resilience with age, making them more susceptible to micro-damage from the same activities that caused no problems at 25. Golfer’s elbow has an annual incidence of roughly 3 to 4 cases per 10,000 people in the United States, and tennis elbow is several times more common than that.
You don’t need to be an athlete. In fact, occupational repetitive strain is the leading driver of both conditions. People in physically demanding jobs, particularly those involving deviated wrist postures, forceful gripping, or hand-arm vibration from power tools, face the highest risk. The condition also tends to develop on the dominant arm, which takes on more repetitive load during most tasks.
Other Risk Factors Beyond Repetition
While overuse is the primary cause, several other factors can make your tendons more vulnerable to breaking down. Smoking impairs blood flow to tendons, slowing repair and making degeneration more likely. Obesity also increases risk, possibly through the added mechanical load on the arms during daily tasks and through metabolic changes that affect tissue health. Certain medications can weaken tendons as a side effect.
Occupational research has found that people with high physical strain at work and those who maintain non-neutral wrist postures throughout the day tend to have a poorer prognosis once the condition develops. This creates a difficult cycle: the same job demands that caused the problem also make it harder to recover.
How Recovery Typically Works
Most people recover with rest and nonsurgical treatment, but the timeline is longer than many expect. Tennis elbow typically takes about six months to resolve, though some cases stretch to 18 months. Golfer’s elbow follows a similar pattern. The slow recovery reflects the nature of tendon degeneration: unlike muscle, tendons have a limited blood supply and heal slowly.
Recovery centers on reducing the load on the affected tendon long enough for tissue repair to catch up. That often means modifying or temporarily stopping the activity that caused the problem, using a forearm brace to redistribute forces away from the damaged tendon, and gradually introducing strengthening exercises that promote healthy collagen remodeling. For people whose jobs caused the condition, ergonomic modifications are essential. Workplace adjustments should focus on minimizing deviated wrist postures, reducing forceful exertions, and building in adequate rest periods between repetitive tasks.
The small percentage of people who don’t improve with conservative treatment over 6 to 12 months may be candidates for procedures that address the degenerated tissue directly. But for the large majority, the combination of load management, time, and progressive strengthening resolves the problem without intervention.