Tennis elbow

Introduction

Tennis elbow, also known as lateral epicondylitis, is a common musculoskeletal condition characterized by pain and tenderness on the outer aspect of the elbow. It affects both athletes and individuals involved in repetitive manual activities. The condition can significantly impact daily activities and occupational performance if left untreated.

Definition and Nomenclature

Definition of Tennis Elbow

Tennis elbow is a tendinopathy involving the common extensor tendon of the forearm, particularly the extensor carpi radialis brevis. It is caused by overuse and repetitive stress on the tendon, leading to microtears and degeneration.

Alternative Names

• Lateral epicondylitis
• Lateral tendinopathy
• Epicondylalgia of the lateral elbow

Differentiation from Other Elbow Conditions

Although often associated with sports activities, tennis elbow differs from conditions such as medial epicondylitis, osteoarthritis, and radial tunnel syndrome. Accurate diagnosis is essential for effective treatment and management.

Epidemiology

Tennis elbow is a prevalent musculoskeletal disorder affecting adults worldwide, particularly those engaged in repetitive forearm activities. Understanding its epidemiological patterns aids in prevention and early intervention.

• Prevalence: Approximately 1–3% of the general population is affected, with higher rates in individuals performing repetitive manual or occupational tasks.
• Age and gender distribution: Most commonly occurs between 35 and 50 years of age, with a slightly higher prevalence in males.
• Occupational and recreational risk factors: High-risk groups include tennis players, painters, carpenters, computer users, and manual laborers involved in repetitive wrist and forearm movements.

Etiology and Risk Factors

The development of tennis elbow is multifactorial, involving mechanical, occupational, and intrinsic factors that contribute to tendon degeneration and pain.

• Overuse and repetitive movements: Frequent extension of the wrist and repetitive gripping motions place stress on the extensor tendons, leading to microtrauma.
• Occupational factors: Activities involving prolonged computer use, manual labor, or tools that require forceful gripping increase the risk of tendon injury.
• Sports-related causes: Racquet sports, particularly tennis, can overload the extensor carpi radialis brevis, especially with improper technique or sudden increase in activity intensity.
• Intrinsic factors: Age-related tendon degeneration, muscular weakness, and joint instability can predispose individuals to developing tennis elbow.

Anatomy Relevant to Tennis Elbow

Understanding the anatomical structures involved in tennis elbow is essential for accurate diagnosis and effective treatment. The condition primarily affects the lateral aspect of the elbow where tendons attach to bone.

• Lateral epicondyle of the humerus: The bony prominence on the outer elbow serves as the attachment point for the common extensor tendon.
• Common extensor tendon: Includes the extensor carpi radialis brevis, extensor digitorum, and extensor carpi radialis longus, with the brevis most commonly implicated in tendon injury.
• Muscles, ligaments, and neural structures: Surrounding muscles contribute to wrist and finger extension, while radial nerve branches provide sensory input to the lateral elbow region.

Pathophysiology

Tennis elbow results from chronic overuse and microtrauma to the extensor tendons, leading to degenerative changes rather than classical inflammation.

• Tendinosis and microtears: Repetitive stress causes microtears in the extensor carpi radialis brevis tendon, resulting in pain and functional impairment.
• Degenerative versus inflammatory processes: Histological studies show fibroblast proliferation, disorganized collagen, and angiofibroblastic hyperplasia rather than acute inflammatory cells.
• Vascular changes and cellular response: Local hypovascularity and poor tendon healing contribute to persistent symptoms and delayed recovery.

Clinical Features

Tennis elbow presents with characteristic signs and symptoms that help differentiate it from other elbow disorders. Recognition of these features is important for diagnosis and management.

• Symptoms: Pain and tenderness over the lateral epicondyle, often radiating down the forearm, exacerbated by gripping or lifting activities.
• Signs: Pain on resisted wrist extension, weakness in grip strength, and localized swelling may be present.
• Functional impact: Difficulty performing daily tasks such as lifting objects, shaking hands, or turning doorknobs, leading to reduced occupational and recreational performance.

Diagnosis

Diagnosis of tennis elbow is primarily clinical, supported by history, physical examination, and imaging when necessary.

• Clinical evaluation and history: Identification of risk factors, onset, and progression of symptoms, and aggravating activities.
• Physical examination maneuvers: Tests such as Cozen’s test, Mill’s test, and resisted middle finger extension help reproduce pain and confirm tendon involvement.
• Imaging studies: Ultrasound and MRI can identify tendon degeneration, tears, or calcifications in persistent or atypical cases.
• Differential diagnosis: Conditions such as radial tunnel syndrome, osteoarthritis, cervical radiculopathy, and medial epicondylitis must be considered to avoid misdiagnosis.

Management and Treatment

Conservative Management

Most cases of tennis elbow respond well to non-surgical interventions aimed at reducing pain, promoting tendon healing, and restoring function.

• Rest and activity modification: Avoiding activities that exacerbate pain, using ergonomic adjustments, and modifying sports techniques.
• Nonsteroidal anti-inflammatory drugs (NSAIDs): Oral or topical NSAIDs help relieve pain and inflammation in the acute phase.
• Physical therapy and stretching exercises: Eccentric strengthening of the extensor muscles, stretching, and gradual load progression improve tendon resilience.
• Bracing and orthotic support: Counterforce straps and wrist splints reduce stress on the extensor tendons during activity.

Interventional Treatment

For patients not responding to conservative measures, minimally invasive interventions may be considered to promote tendon healing and reduce pain.

• Corticosteroid injections: Provide short-term pain relief but may not improve long-term outcomes and repeated use may weaken the tendon.
• Platelet-rich plasma (PRP) therapy: Autologous platelet injections aim to enhance tendon healing through growth factor release.
• Extracorporeal shockwave therapy (ESWT): Non-invasive treatment using acoustic waves to stimulate tissue repair and reduce pain.

Surgical Management

Surgery is reserved for patients with persistent symptoms who do not respond to conservative or interventional treatments over several months. Surgical procedures aim to remove degenerated tendon tissue and promote tendon healing.

• Indications for surgery: Chronic pain lasting more than 6–12 months, failed conservative therapy, and significant functional impairment.
• Open versus arthroscopic techniques: Open surgery involves direct debridement of the extensor tendon origin, while arthroscopic surgery allows minimally invasive tendon repair and assessment of intra-articular structures.
• Postoperative rehabilitation: Gradual mobilization, physical therapy, and progressive strengthening exercises are essential to restore range of motion, muscle strength, and function.

Prognosis

The prognosis for tennis elbow is generally favorable, especially with early diagnosis and adherence to treatment protocols. Most patients experience significant pain relief and functional improvement within months.

• Expected recovery timeline: Conservative management typically leads to improvement within 6–12 weeks, while interventional or surgical approaches may require longer rehabilitation.
• Factors influencing prognosis: Age, duration of symptoms, severity of tendon degeneration, adherence to therapy, and occupational demands can affect recovery.
• Risk of recurrence: Recurrence is possible, particularly if aggravating activities are resumed prematurely or if underlying risk factors are not addressed.

Prevention

Preventive strategies for tennis elbow focus on reducing repetitive stress on the extensor tendons, improving strength and flexibility, and promoting ergonomic practices.

• Ergonomic adjustments and proper technique: Using appropriate tools, modifying sports techniques, and maintaining correct posture during activities can reduce tendon strain.
• Strengthening and flexibility exercises: Regular exercises targeting the forearm extensors, wrist, and shoulder improve muscle endurance and joint stability.
• Education on activity modification: Teaching individuals to avoid overuse, take breaks, and gradually increase activity intensity helps prevent injury.

References

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