Courtesy: Prof Nabil Ebraheim, University of Toledo, Ohio, USA

Tennis Elbow (Lateral Epicondylitis)

Definition

• Tennis elbow, also called lateral epicondylitis, is an overuse injury.

• It causes:

  • Inflammation

  • Tendinosis

  • Lateral elbow pain

• The pathology occurs at the origin of the Extensor Carpi Radialis Brevis (ECRB) muscle.

• Pain is located on the outer (lateral) side of the elbow.

• Symptoms may interfere with:

  • Sleep

  • Daily activities

  • Carrying groceries

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Etiology and Risk Factors

• It is the most common cause of elbow pain.

• Approximately 50% of tennis players develop tennis elbow.

• Contributing factors in tennis players:

  • Incorrect grip size

  • Poor swing technique

• Also affects workers performing:

  • Heavy lifting

  • Repetitive gripping

  • Use of heavy tools

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Pathology

• The condition usually begins with microtears at the origin of the Extensor Carpi Radialis Brevis.

• Caused by eccentric overload.

• Aggravated by:

  • Repetitive wrist extension

  • Forearm pronation

• Tendon pathology shows:

  • Disorganized collagen

  • Angiofibroblastic hyperplasia

  • Vascular hyperplasia

  • Fibroblast hypertrophy

  • Replacement of tendon fibers with vascular granulation tissue

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Clinical Features

• Lateral-sided elbow pain

• Pain with gripping

• Decreased grip strength

• Pain with repetitive wrist extension

• Tenderness around the lateral epicondyle

• Point tenderness on palpation over the lateral epicondyle

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Physical Examination

• Diagnosis is based on symptoms and physical examination.

• Provocative test:

  • Resisted wrist extension

  • Elbow fully extended

  • Reproduction of pain at the lateral epicondyle

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Differential Diagnosis

Radial Tunnel Syndrome

• Occurs in approximately 5% of patients.

• Caused by compression of the posterior interosseous nerve.

• Pain is located:

  • 3–4 cm distal and anterior to the lateral epicondyle.

• Should be suspected if the patient does not recover as expected with tennis elbow treatment.

• Diagnostic approach:

  • Injection into the radial tunnel to assess response.

Other Conditions to Rule Out

• Cervical disc pathology

• Triceps tendinitis

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Investigations

• Diagnosis is primarily clinical.

• X-rays are usually normal.

• Rarely, calcification may be seen.

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Treatment

Nonoperative Treatment

• Activity modification

• Nonsteroidal anti-inflammatory medication

• Ice

• Physiotherapy:

  • Tendon gliding exercises

  • Eccentric conditioning

  • Strengthening program

• Bracing

• Up to 95% success rate with nonoperative treatment.

• Improvement may take 6–12 months.

• Condition often improves with time regardless of the conservative method chosen.

Injection Therapy

• Steroid injection (up to three injections)

  • Useful for controlling acute symptoms.

• Platelet-Rich Plasma (PRP) injection

• Ultrasound guidance may be helpful during injection.

• Physiotherapy may provide better symptomatic relief at one year compared to steroid injection.

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Surgical Treatment

• Considered the last resort.

• Procedure involves:

  • Release and debridement of the Extensor Carpi Radialis Brevis origin.

• Excessive debridement or release may injure the lateral collateral ligament.

• This may lead to posterolateral rotatory instability of the elbow.

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Extensor Carpi Radialis Brevis (ECRB) Muscle

Origin

• Lateral epicondyle of the humerus

• Part of the common extensor tendon

Insertion

• Base of the dorsal aspect of the third metacarpal

Innervation

• Radial nerve

Function

• Wrist extension

• Abduction of the hand at the wrist joint

Location

• Located in the second dorsal compartment on the radial side of Lister’s tubercle.

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Other Conditions Involving the ECRB Muscle

1. Intersection Syndrome

• Inflammation at the crossing of:

  • First dorsal compartment

  • Second dorsal compartment

• The second dorsal compartment contains the Extensor Carpi Radialis Brevis.

• Caused by repetitive wrist extension.

• Tenderness is present on the dorsoradial aspect of the forearm.

• Approximately 5 cm proximal to the wrist joint.

• Involves intersection of:

  • Extensor Carpi Radialis Longus

  • Extensor Carpi Radialis Brevis

  • Abductor Pollicis Longus

  • Extensor Pollicis Brevis

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2. Posterolateral Elbow Instability

• May occur after excessive release of the Extensor Carpi Radialis Brevis tendon during tennis elbow surgery.

• Due to proximity of the ECRB origin to the ulnar humeral (lateral ulnar collateral) ligament.

• Injury to this ligament may cause posterolateral elbow instability.

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3. Tendon Transfer in High Radial Nerve Palsy

• High radial nerve palsy results in wrist drop.

• Caused by paralysis of the extensor tendons.

• Surgical management:

  • Pronator teres is transferred to the Extensor Carpi Radialis Brevis.

• Purpose:

  • Restore wrist extension