Extensor Carpi Ulnaris Trigger Points

Introduction

The extensor carpi ulnaris (ECU) is a key forearm muscle involved in wrist extension and ulnar deviation (moving the wrist toward the pinky side). When trigger points develop in this muscle, they can cause pain in the outer forearm, wrist, and hand, often mimicking tennis elbow, ulnar nerve compression, or arthritis.

Name and Area

  • Name: Extensor Carpi Ulnaris (ECU)

  • Area: Located on the posterior forearm, running from the humerus and ulna to the base of the fifth metacarpal.

Indications

Extensor carpi ulnaris trigger points may contribute to:

  • Pain Along the Outer Forearm and Wrist (Mistaken for Tennis Elbow or Wrist Sprains)

  • Pain That Extends to the Pinky Side of the Hand (Can Mimic Ulnar Nerve Entrapment)

  • Weakness in Grip Strength (Difficulty Holding Objects, Opening Jars, or Writing)

  • Pain When Extending the Wrist or Twisting the Forearm (E.g., Using a Screwdriver, Turning a Key)

  • Wrist Instability or Clicking Sounds (Common in Athletes and Tennis Players)

  • Pain When Carrying Heavy Bags or Lifting With the Palm Facing Down

Pain from this muscle is often mistaken for wrist tendinitis or ulnar nerve compression.

Muscle Action

  • Extends the Wrist: Raises the hand upward.

  • Ulnar Deviation: Moves the wrist toward the pinky side.

  • Stabilizes the Wrist During Grip Movements: Works with the extensor carpi radialis muscles to balance the wrist.

The ECU is crucial for stabilizing the wrist during repetitive hand use, sports, and occupational tasks that require grip strength and forearm rotation.

Signs and Symptoms

Individuals with extensor carpi ulnaris trigger points often report:

  • Pain on the Outer Forearm That Worsens With Wrist Movements

  • Pain That Travels to the Pinky Finger and Hand (Mimicking Ulnar Nerve Compression)

  • Weak Grip Strength, Especially With Heavy or Prolonged Use

  • Burning or Tightness in the Forearm After Extended Typing or Writing Sessions

  • Pain When Lifting Objects With the Palm Facing Down

  • Pain When Twisting the Wrist (Turning a Doorknob, Using Tools, Tennis Backhand Movements)

Pain worsens with repetitive wrist movements, gripping, or prolonged computer use.

Perpetuating Factors

Common causes of extensor carpi ulnaris trigger points include:

  • Repetitive Wrist Extension Movements (Typing, Gaming, Tennis, Golf, Weightlifting, Rock Climbing)

  • Frequent Twisting Motions (Using a Screwdriver, Wrench, or Turning Keys)

  • Carrying Heavy Bags or Suitcases With the Wrist Extended or Deviated

  • Holding the Wrist in an Awkward Position for Long Periods (Mouse Use, Driving, Holding a Steering Wheel)

  • Poor Ergonomics at Workstations (Incorrect Keyboard and Mouse Positioning)

  • Tennis or Golf Overuse (Particularly Backhand Movements or Wrist Cocking in Golf Swings)

Trigger Point Referral Pattern

Trigger points in the extensor carpi ulnaris refer pain to:

  • The outer forearm and wrist (Often Misdiagnosed as Wrist Tendinitis)

  • The pinky finger and lateral hand (Can Resemble Ulnar Nerve Entrapment or Carpal Tunnel Syndrome)

  • The ulnar side of the wrist joint (Mistaken for Arthritis or Ligament Sprains)

Pain from this muscle is often confused with lateral epicondylitis (tennis elbow) or nerve compression syndromes.

Differential Diagnosis

Extensor carpi ulnaris trigger points may be mistaken for:

  • Tennis Elbow (Lateral Epicondylitis) – Outer Elbow Pain and Weak Grip Strength

  • Ulnar Nerve Compression (Pain, Weakness, or Numbness in the Pinky Side of the Hand)

  • Carpal Tunnel Syndrome (Pain or Numbness in the Hand and Fingers, Particularly at Night)

  • Wrist Extensor Tendinitis (Pain and Stiffness in the Wrist and Forearm After Repetitive Use)

  • Cervical Radiculopathy (C7 Nerve Root Compression, Leading to Forearm and Wrist Pain)

A thorough wrist, elbow, and nerve examination is necessary for correct diagnosis.

Associated Trigger Points

Extensor carpi ulnaris trigger points often co-exist with:

  • Flexor Carpi Ulnaris (Pain on the Inner Wrist and Hand, Affects Grip Strength)

  • Extensor Carpi Radialis Longus and Brevis (Pain Along the Forearm and Wrist, Affects Lifting Movements)

  • Brachioradialis (Pain in the Forearm During Rotation Movements)

  • Supinator (Pain in the Outer Forearm During Pronation and Supination Movements)

Anatomy and Innervation

Muscle Origin Insertion Innervation
Extensor Carpi Ulnaris Lateral epicondyle of humerus, posterior border of ulna Base of the fifth metacarpal Radial nerve (C7–C8)

The ECU is innervated by the radial nerve, which also controls wrist and finger extensors.

Patient Examination

A comprehensive examination should include:

  • Palpation: Identify tender nodules along the lateral forearm, near the wrist and pinky side of the hand.

  • Resisted Wrist Extension Testing: Assess pain and weakness when lifting the hand upward against resistance.

  • Grip Strength Testing: Determine if pain affects endurance when holding objects for long periods.

  • Ulnar Deviation Testing: Check for discomfort when moving the wrist toward the pinky side.

  • Ulnar Nerve Compression Testing: Rule out nerve-related causes of wrist and hand pain.

Corrective Actions

Manual Therapy

  • Trigger Point Release: Apply sustained pressure along the lateral forearm and wrist extensors.

  • Soft Tissue Mobilization: Massage and myofascial techniques to improve blood flow and reduce tightness.

Stretching

  • Wrist Extensor Stretch: Extend the arm with the palm facing down, gently pull the fingers toward the body.

  • Ulnar Deviation Stretch: Slowly move the wrist toward the thumb side to stretch the ECU.

Strengthening Exercises

  • Wrist Extension With Resistance Bands: Strengthens the ECU and surrounding wrist muscles.

  • Grip Strength Drills: Improves forearm endurance and function.

  • Ulnar Deviation Strengthening: Strengthens the ECU and improves wrist stability.

Postural and Ergonomic Adjustments

  • Modify Keyboard and Mouse Positioning (Reduce Wrist Extension and Strain)

  • Use an Ergonomic Mouse or Wrist Support (Prevents Overuse Injuries)

  • Take Frequent Breaks During Repetitive Tasks (Allows Forearm Muscles to Recover)

Summary Table: Extensor Carpi Ulnaris Trigger Points

Field Details
Name & Area Extensor Carpi Ulnaris; Lateral forearm, spanning humerus and ulna to wris
Indications Forearm, wrist, and pinky-side hand pain, weak grip strength
Muscle Action Wrist extension, ulnar deviation, grip stabilization
Signs & Symptoms Pain in the outer forearm, wrist weakness, pain when twisting the wrist
Perpetuating Factors Repetitive wrist use, prolonged gripping, poor ergonomics, excessive typing
Trigger Point Referral Outer forearm, pinky side of wrist, hand
Differential Diagnosis Tennis elbow, ulnar nerve compression, carpal tunnel syndrome, wrist extensor tendinitis
Associated Trigger Points Flexor carpi ulnaris, extensor carpi radialis longus/brevis, brachioradialis
Anatomy & Innervation Radial nerve (C7–C8)
Corrective Actions Manual therapy, stretching, strengthening, ergonomic changes

➡️ Learn more about Trigger Points

Sources:

  • Travell, J. G., & Simons, D. G. (1983). Myofascial Pain and Dysfunction: The Trigger Point Manual (2nd ed.). Williams & Wilkins.

  • Simons, D., & Travell, J. (1999). The Trigger Point Manual, Volume 2: The Lower Extremities. Williams & Wilkins.