Extensor Carpi Ulnaris Tendinopathy

Other Names

• Extensor Carpi Ulnaris Tendinopathy
• Tendinopathy
• ECU Tendinitis
• Snapping ECU
• ECU Stenosing tenosynovitis
• ECU tendinosis
• ECU instability
• ECU rupture

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Background

• This page refers to tendon pathology of the extensor carpi ulnaris which includes tendinitis, tendinosis, tenosynovitis, tendon instability and rarely rupture

History

• Needs to be updated

Epidemiology

• Most limited to case reports/ case series
• Wrist injuries make up about 8.9% of all sports injuries
• Tennis
  • Prevalence of 1 case per 18 players/year
  • Male > female
  • ECU instability (42%), tenosynovitis (50%), rupture (8%)
• Golf
  • 2009 European PGA tour study reported 30% of professional golfers had a wrist injury (need citation)
  • LPGA European professional golfers had 54% incidence of wrist injuries (need citation)
• Rugby
  • One study of seven English Rugby leagues found an incidence of 1 ECU injury per 60 players/year (need citation)

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Introduction

Diagrammatic representation of the change of position of the extensor carpi ulnaris tendon between pronation and supination. There is an angulation of the tendon as it exits the subsheath in supination and flexion.

General

• Pathology occurs across a spectrum of tenosynovitis, tendinosis, tendon disruption and instability
• Patients typically present with ulnar sided wrist pain, worse with extension
• It is important to distinguish stable from unstable conditions
• Imaging with dynamic ultrasound or MRI is useful

Pathophysiology in Athletes

• Common features of ECU injuries
  • Loading of the wrist when the ECU is vulnerable during wrist flexion during supination and ulnar deviation
  • Sudden lateral force applied to the wrist when the tendon is engaged in strong isometric contraction

Tenosynovitis

• Caused by repetitive wrist flexion and extension, especially in supination
• Tennis
  • Athletes will present with sudden onset of ulnar-sided wrist pain that prevents further play
  • Symptoms resolve following rest and then recur when attempting to play again
• Golf
  • Associated with the use of hard practice mats, playing off excessively hard ground
• In non athletes, consider rheumatoid arthritis
• Stenosing tenosynovitis is rare, not documented in athletes
• Tendon instability may be a contributing factor

Tendinosis/ Tendinopathy

• Adaptive response from overuse, repetitive stress and/or trauma
• Athletes typically report a more gradual onset of ulnar sided wrist pain

Tendon Instability

• Sometimes termed snapping ECU
• Can range from subluxation to gross dislocation with forearm locking
• Golf
  • Subluxation occurs in the leading wrist (that is wrist facing the target)
  • Wrist moves from radial deviation to neutral position at impact
  • Leading wrist is forced into ulnar deviation
  • Risk increases if the club strikes a hard object on the ground
  • This creates a 'traumatic hinge' into radial deviation
• Rugby
  • Forearm is n maximal supination, wrist is flexed and ulnar deviated when carrying the ball
  • Sudden increase in ECU isometric contraction can occur when someone tries to strip the ball
  • Subsequently, a traumatic tear of sub sheath and acute subluxation can occur
  • Athletes describe this as a painful snap at the moment of impact
• May be incidental finding and asymptomatic
• Results from injury to the Sixth Dorsal Compartment
• Most commonly occurs due to a single, acute injury
• Disruption can occur from (a) periosteal stripping on the ulnar wall, (b) radial tear, and (c) ulnar tear

Tendon Rupture

• Rare phenomenon limited to case reports

Anatomy of Extensor Carpi Ulnaris

• Description
  • Originates on lateral epicondyle of humerus, posterior surface of ulna
  • Courses through the sixth dorsal compartment
  • Inserts on the medial side of the fifth metacarpal
  • Contributes to wrist extension and flexion
  • Extension contribution is greater in supination, as is risk of injury
• Anomalous ECU tendon
  • One symptomatic patient had abnormal insertion of the tendon slip into the radial inner side of the 6th compartment

Associated Conditions

• TFCC Tear
  • 43% of patients with foveal tears demonstrating ECU tenosynovitis on MRI
• Distal Radioulnar Joint Instability
• Ulnocarpal Pathology

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Risk Factors

• Sports
  • Tennis
  • Golf
  • Rugby
• Systemic
  • Rheumatoid Arthritis

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Differential Diagnosis

The ECU synergy test is performed by having the patient radially deviate the thumb against resistance. Note that the ECU tendon bowstrings against the skin (large arrow). * Extensor Carpi Ulnaris Synergy Test

Differential Diagnosis Ulnar Sided Wrist Pain

• TFCC Injury
• Lunotriquetral Ligament Injury
• Distal Radioulnar Joint Pain
• Ulnar Styloid Fracture
• ECU Tendinopathy

Differential Diagnosis Wrist Pain

• Fractures
  • Distal Radius Fracture
    • Bartons Fracture
    • Chauffers Fracture
    • Colles Fracture
    • Die-Punch Fracture
    • Radial Styloid Fracture
    • Smiths Fracture
  • Distal Ulna Fracture
  • Carpal Fractures
    • Scaphoid Fracture
    • Lunate Fracture
    • Triquetrum Fracture
    • Pisiform Fracture
    • Trapezium Fracture
    • Trapezoid Fracture
    • Capitate Fracture
    • Hamate Fracture
  • Essex Lopresti Fracture
• Dislocations
  • Wrist Dislocation (Radiocarpal and/or Ulnocarpal)
  • Carpometacarpal Joint Dislocation
  • Distal Radioulnar Joint Dislocation
  • Lunate Dislocation
  • Perilunate Dislocation
• Instability & Degenerative
  • Scapholunate Instability
  • Lunotriquetral Instability
  • Scaphoid Nonunion Advanced Collapse
  • Distal Radial Ulnar Joint Instability
  • Kienbocks Disease
  • Dorsal Wrist Impingement
  • Carpal Instability
• Tendinopathies & Ligaments
  • De Quervain's Tenosynovitis
  • Intersection Syndrome
  • TFCC Injury
  • Wrist Tendinopathies
  • Extensor Carpi Ulnaris Tendinopathy
• Neuropathies
  • Carpal Tunnel Syndrome
  • Pronator Teres Syndrome
  • Anterior Interosseus Nerve Syndrome
  • Posterior Interosseus Nerve Syndrome
  • Guyon Canal Syndrome
  • Wartenbergs Syndrome
• Pediatric Considerations
  • Distal Radial Epiphysitis (Gymnast's Wrist)
  • Torus Fracture
• Arthropathies
  • Wrist Osteoarthritis
  • Scaphotrapeziotrapezoidal Joint Arthritis (STT Arthritis)
  • Rheumatoid Arthritis
  • Gout
• Cartilage
  • Osteochondral Defect
• Vascular
  • Hypothenar Hammer Syndrome
• Other
  • Ganglion Cyst of Wrist
  • Ulnar Impingement Syndrome
  • Infectious Tenosynovitis

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Clinical Features

ECU Synergy Test

History

• Patients present with ulnar sided wrist pain
• Often the pain is worse with extension, adduction
• Localized swelling may or may not be present
• Symptoms may improve with rest, recur when returning to sport
• Timing of symptoms can help discriminate between acute and chronic cases
• With sheath disruption, they may describe a snap, pop or tear
• Subluxation, when present, can be painful or asymptomatic
• In patients with a tendinopathy, the pain is characterized as as an ache
  • Will become a sudden searing pain with active use of the muscle

Physical Exam

• Palpate along the length of the ECU tendon
  • Start at the base of the 5th metacarpal and work proximally
• Pain on resisted extension, ulnar deviation is pathognomonic
• Weakness and pain are frequently associated

Special Tests

• ECU Synergy Test: have the patient radially deviate the thumb against resistance
• Ice Cream Scoop Test: Make ice cream scooping maneuvers against resistance to sublux the tendon

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Evaluation

Axial ultrasound images of the normal extensor carpi ulnaris (ECU) tendon. In wrist pronation (A) the tendon lies within the ulnar groove (white arrows). The subsheath (black arrows) is immediately superficial to the tendon and attaches to the ulna. Distal to the ulna (B) the tendon (curved white arrow) lies superficial to the meniscal homologue of the triangular fibrocartilage complex (asterix) and the triquetrum. The extensor retinaculum (broken black arrows) displays hyper-reflective and hyporeflective properties due to the effects of anisotropy. In wrist supination (C) the tendon (curved white arrow) moves to the ulnar aspect of the groove (white arrows), and a small area of echo bright fatty tissue lies in the radial aspect of the groove (black asterisk). The tendons of the fourth and fifth compartments (broken white arrows) now lie in closer relation to the ECU tendon.

Axial T2 fat saturated MRI of the wrist in a rugby league player following an acute extensor carpi ulnaris subsheath injury. The tendon (white arrow) is subluxed in an ulnar direction and the subsheath is torn at its radial insertion on the ulna (black arrow). There is associated marrow oedema in the head of the ulna (curved white arrow). There were associated injuries including an acute triangular fibrocartilage tear, and there is an effusion in the distal radioulnar joint.

Radiographs

• Standard Radiographs Wrist
  • Typically normal

Ultrasound

• Advantages
  • Can be used for dynamic assessment
  • Doppler evaluation for inflammation
  • Evaluate contralateral ECU tendon
• Normal ECU
  • Flattened ovoid configuration in transverse section seen at the level of the ulnar groove
  • Tendon sheath becomes more prominent distal to ulnar styloid and should not be mistaken for tenosynovitis
  • Extensor retinaculum is a thin structure seen dorsally
• Tenosynovitis
  • Presence of anechoic, easily compressible fluid surrounding tendon sheath
  • Vascularity on doppler should be minimal or absent
  • Underlying tendon can appear normal
  • Echogenic, hypervascular tendon sheath more likely associated with inflammatory arthropathy
• Tendinopathy
  • Early tendon thickening may be subtle, useful to compare to contralateral limb
  • Tendon will become thicker as disease progresses
  • Poorly defined, low echo areas can be seen within the tendon substance
  • On doppler, tendon neovascularization may be present
• Tendon rupture
  • Tendon is not visualized within dorsal compartment and distally
  • Proximal muscle atrophy
  • In acute ruptures, retraction can vary and soft tissue hemorrhage is present
• Tendon subluxation
  • Best visualized in supination, flexion and ulnar deviation
  • Displacement of up to 50% of tendon from the ulnar groove can be seen in asymptomatic patients
  • Failure of tendon to return to normal position in pronation is uncommon

MRI

• Tendinopathy
  • Moderate increased signal
• Partial tendon tear
  • Clefs or splits within tendon on transverse view
  • Attenuation of tendon thickness in long axis
• Tendon subluxation
  • Does not reliably show sub sheath tear
  • Other findings include tendinopathy, tenosynovitis, marrow edema
  • Acute rupture will be associated with edema, hemorrhage

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Classification

• Can be divided into:
  • Acute Tenosynovitis
  • Tendinopathy/ Tendinosis
  • Subluxation/ Instability
  • Rupture

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Management

Ulnar Gutter Brace

ECU Tendinopathy

• Initial treatment
  • Rest, activity modification
  • Ulnar Gutter Splint or ulnar gutter brace in 30° wrist extension, ulnar deviation for 2-3 weeks
  • Can consider splinting in pronation so tendon sits in groove
  • Physical Therapy
  • NSAIDS
• Corticosteroid Injection in the Sixth Extensor Compartment
  • Should be considered if not improving
  • Can be useful diagnostically
  • Performed under ultrasound guidance
• Surgical co-compartment release
  • Can be considered if tendinosis is persistent

ECU Instability

• Asymptomatic
  • These patients may not require treatment
• Symptomatic
  • If tendinosis is present, conservative management is unlikely to be succesful
• Early diagnosis of acute, traumatic unstable ECU tendon
  • Reduce subluxed tendon
  • Immobilize for 6 weeks (as described above)
  • One study of 28 professional tennis players reported success when immobilized for up to 4 months
• Chronic subluxation
  • Surgical reconstruction of 6th extensor may be indicated
  • In one study, 20 of 21 patients returned to sport/ work at an average of 17 months

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Rehab and Return to Play

ECU tendinopathy rehab exercises

Extensor carpi ulnaris tendon rehab exercises

Rehabilitation

• Phase 1: Acute/Protective Phase (0-2 weeks)
  • Goals: reduce pain, inflammation, protect from further injury, maintan general fitness
  • Initially with immobilization, activity modification, ice, NSAIDS, relative rest
  • Criteria to progress: reduction in resting pain, minimal tenderness over ECU tendon, able to perform gentle ROM painlessless
• Phase 2: Early Rehabilitation Phase (2-4 weeks)
  • Goals: restore pain free ROM, begin gentle strengthening, improve proprioception
  • Wrist ROM exercises: Gentle active flexion/extension, radial/ulnar deviation (pain-free range)
  • Forearm ROM: Pronation and supination exercises
  • Isometric strengthening: Wrist extension and ulnar deviation (submaximal, pain-free)
  • Proprioceptive training: Wrist position sense exercises in open kinetic chain
  • Gradual weaning from splint: Remove for exercises and activities of daily living as tolerated
  • Criteria to progress: pain free ROM, pain reduction from phase 1 with exercise, no increase in symptoms with ADLs
• Phase 3: Progressive Strengthening Phase (4-8 weeks)
  • Goals: progressive tendon loading, restore strength and endurance, begin sport specific movements
  • Eccentric strengthening: ECU-specific eccentric exercises (slow speed, low intensity initially, gradual progression)
  • Concentric strengthening: Wrist extensors, flexors, and ulnar/radial deviators
  • Pronator quadratus strengthening: Important for ulnar-sided stability
  • Closed kinetic chain exercises: Weight-bearing wrist exercises, planks with wrist variations
  • Progressive resistance: Theraband → light weights → heavier resistance
  • Sport-specific movements: Begin introducing sport-specific motions at reduced intensity (50-70%)
  • Criteria to progress: strength 80% or more contralateral side, pain free with strength exercises, tolerate sport specific movements painlessly up to 70% intensity
• Phase 4: Return to Sport Phase (8-12 weeks)
  • Goals: restore full strength and power, complete sport scific training, safe return to competition
  • dvanced strengthening: High-load, sport-specific resistance training
  • Plyometric exercises: For overhead and racquet sports (medicine ball throws, etc.)
  • Sport-specific drills: Progressive return to full training
• Proprioceptive training: Sport-specific balance and coordination drills
  • Gradual return to play: Non-contact → contact → full competition

Rehab Protocol PDFs

• Extensor Carpi Ulnaris (ECU) Post-Op Exercises PDF
• Extensor Carpi Ulnaris Tendonitis Handout and Exercises PDF
• Extensor Tendon Repair Protocol PDF
• Wrist Tendinitis Exercises PDF

Return to Play/ Work

• Return to Play Criteria
  • Pain: ≤1/10 with all activities including sport-specific movements
  • Strength: ≥90% of contralateral side (grip strength, wrist extension, ulnar deviation)
  • ROM: Full, pain-free range of motion
  • Functional testing: Able to perform all sport-specific skills without compensation
  • Anatomical healing: Resolution of tenderness to palpation over ECU tendon
  • Psychosocial readiness: Athlete confidence in returning to sport
  • No risk to others: Athlete can safely participate without endangering other participants
• Sport specific considerations
  • Tennis/Racquet Sports: Focus on backhand mechanics, grip modification, equipment assessment
• Golf: Address swing mechanics, particularly follow-through phase
  • Contact Sports: May require protective taping or bracing initially upon return

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Prognosis and Complications

Prognosis

• General
  • Favorable prognosis with conservative management, most people improve in about 8-12 weeks
• Nonoperative
  • The majority of ECU tendinopathy cases resolve with nonoperative treatment
  • recurrence of symptoms is common if athletes return to sport prematurely or if underlying biomechanical issues are not addressed

Complications

• Progression to chronic tendinopathy and wrist pain
• Inability to return to sport
• Instability and sublixation

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See Also

Internal

• Wrist Pain Main
• Physical Exam Wrist
• Hand and Wrist Anatomy

External

• https://www.sportsmedreview.com/blog/review-of-extensor-carpi-ulnaris-tendinopathy/

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