EXTENSOR CARPI ULNARIS
TENDINOPATHY
• Anatomy
• Biomechanics
• Injury Pathology
• Assessment
• Treatment
OVERVIEW
• Origin:
− Middle third of the posterior border of ulna
− Lateral epicondyle of humerus
• Insertion:
− Dorso-ulnar aspect of the base of the 5th
metacarpal
• Innervation:
− Posterior interosseous nerve (C7 & C8), the continuation of deep branch of radial
nerve
• Main Action:
− Wrist extension and ulnar deviation. It also assists to provide stability at the wrist.
• Fibro-osseous tunnel
– Distal ulna - ulnar groove
– 1.5 to 2cm length band of connective tissue (ECU subsheath)
• Stabilises the tendon at the level of the
distal ulna
• ECU subsheath lies deep to the extensor
retinaculum
• The overlying extensor retinaculum
courses over the ECU and distal ulna to
attach to the pisiform and triquetrum.
Does not play a role in stabilising the
ECU tendon.
• Linea jugata provides dynamic stability
• Linea Jugata
• Linea Jugata
• Shallow osseous groove
• Anomalous tendinous slips (EDM)
• Pronation
– Straight course
– Minimal force on subsheath
• Supination
– ECU radially translates forming ulnar directed obtuse angle
– This angle is further increased with wrist flexion and ulnar deviation – Maximal force on subsheath
1. ECU Subluxation
2. ECU Tenosynovitis
3. ECU Rupture
• Associated Injuries / Differential Diagnosis
– TFCC injury
– Lunotriquetral instability – DRUJ injury
– Ulnar styloid non-union
• Requires an injury to the ECU subsheath
• ECU tendon is no longer maintained within its fibro-osseous
groove
• Usually occurs as a result of acute injury
– Forceful supination, flexion and ulnar deviation
• Tennis, golf, weight lifting, rodeo • Cricket, forceful twisting of a drill
• Can develop into a chronic injury if left untreated
Injury is classified into three groups:
A. Stripping injury
B. Ulnar sided rupture of subsheath
C. Radial sided rupture of subsheath
A. Stripping injury
− ECU subsheath is stripped at its ulnar attachment, forming a false pouch into which the ECU tendon can sublux (supination)
Stripping of subsheath at ulnar attachment resulting in subluxation during supination Normal subsheath
preventing subluxation
B. Ulnar sided rupture of subsheath
– Likely most common pattern of injury
– Subluxes in supination with relocation of tendon upon pronation
C. Radial sided rupture of subsheath
– Tendon is more likely to relocate lying above the ruptured subsheath. – Functional healing of the tendon is prevented
Supination Pronation
Ulnar sided rupture
Radial sided rupture
Relocates beneath ruptured subsheath
Relocates atop ruptured subsheath
ECU Tenosynovitis & Tendinosis
• Insidious onset
• Chronic stress is placed upon the tendon resulting in
inflammation of its synovial lining, causing tenosynovitis
– Office workers, Boiler maker, Chicken Treat
• Over time, stress may also lead to tendon degeneration
and altered collagen content, resulting in tendinosis with
or without partial tears.
• Second most common site of wrist tendinopathy in
athletes
– Racquet sports, golf, rowing
• Blue arrow = fluid surrounding the ECU tendon • Red asterisk = reactive marrow oedema
• Yellow asterisk = Normal ECU tendon • Red arrow = ECU subsheath
• Blue arrow = extensor retinaculum
ECU Tenosynovitis & Tendinosis
• Rare
• Characteristic cascade of events
– Initial acute luxation event
– Low grade persistent pain (often with accompanying tenosynovitis) – Local steroid injections (may have provided temporary relief)
– Increasing pain limits wrist activity, and subsequent imaging reveals the tendon rupture
• Decreased grip strength
• Tendon is absent
• Red arrow = subsheath is thickened
• Red arrowhead = chronically torn from radial aspect
• Location of pain &/or swelling
– Dorso-ulnar wrist
• Onset of symptoms
– Acute vs. gradual onset
• Mechanism of injury
– Forceful supination, flexion, ulnar deviation – Repetitive ulnar deviation
• Tendon stability
– Painful snapping or clicking sensation of the ECU tendon during
provocative testing
• Active supination • Passive supination
• Active supination, flexion and ulnar deviation
• MMT
– Resisted wrist extension and ulnar deviation – ECU synergy test (Ruland & Hogan 2008)
1. Elbow flexed 90°; forearm in full
supination; wrist neutral; fingers in full extension
2. Examiner grasps patients thumb and middle finger and palpates the ECU tendon with the other hand. The patient then abducts the thumb against resistance
3. Presence of both ECU and FCU muscle contraction is confirmed
4. Re-creation of pain along the dorsal ulnar aspect of the wrist is considered to be a positive test for ECU tendonitis
• MRI (supination)
• Dynamic ultrasound
(pronation & supination)
• Rest
• NSAIDs
• Immobilisation (splinting or casting)
• Ergonomic assessment
• Activity modification
• ECU Subluxation
– Maintain forearm in pronation. Wrist in slight extension and radial deviation
– 6-12 weeks
– Mixed results in literature
• ECU Tenosynovitis
– Ulnar gutter to prevent ulnar deviation – Advise patient to avoid forearm rotation – 3-6 weeks
Activity Analysis & Modification
• Activity Analysis
– Identification of tasks involving repetitive ulnar deviation
– Ergonomic assessment
• Activity Modification
– To enable the person to continue with activity
• Use other hand • Alternative grip
Ergonomic Equipment
• Avoid ulnar deviation
– Whale mouse: designed to promote a relaxed hand position and neutral deviation at the wrist
– Split keyboard: maintains neutral alignment
• Indications:
– ECU tenosynovitis/tendinosis who remain symptomatic despite conservative treatment
– Torn subsheath ends widely separated
– Tendon lies outside the torn subsheath (radial sided tears) – ECU rupture
• Corticosteroid injection (with caution)
• Surgery
– Direct repair
– Subsheath reconstruction
• Radially based extensor retinacular flap • Free retinacular graft
– Sulcus deepening
– Tenosynovectomy (+/- tendon debridement)
– Tendon graft from palmaris longus for ECU ruptures
Medical Management
Conclusion
• Important to have an understanding of the different types of
injuries that can occur as this will affect your treatment plan
– ECU subluxation versus ECU tenosynovitis – Start by looking at the mechanism of injury
Conclusion
• ECU subluxation
– Acute injury – forceful supination, flexion, ulnar deviation – Focus is on limiting supination
– Sugar tong versus wrist gauntlet
– Need for further study into the effectiveness of splinting for ECU subluxation
• Does the location of the tear have an impact i.e. ulnar versus radial sided subsheath tears
Conclusion
• ECU tenosynovitis
– Gradual onset – repetitive ulnar deviation – Focus is limiting ulnar deviation
– Importance of OT role in activity analysis and modification. – ECU synergy test
Allende, C., Le Viet, D. (2005). Extensor Carpi Ulnaris Problems at the Wrist – Classification, Surgical Treatment and Results.
Journal of Hand Surgery, 30B (3), 265-272.
Inoue, G., Tamura, Y. (1998). Recurrent dislocation of the extensor carpi ulnaris tendon. British Journal of Sports Medicine, 32,
172-177.
Jeantroux, J., Becce, F., Guerini, H., Montalvan, B., Le Viet, D., Drape, JL. (2011). Athletic injuries of the extensor carpi ulnaris subsheath: MRI findings and utility of gadolinium-enhanced fat-saturated T1-weighted sequences with wrist pronation and supination. European Society of Radiology, 21, 160-166.
Thomas, G.J. (2012). Pathologies of the Extensor Carpi Ulnaris (ECU) Tendon and its Investments in the Athlete. Hand Clinics, 28,
345-356.
Patterson, S., Picconatto, W., Alexander, J., Johnson, R. (2011). Conservative Treatment of an Acute Traumatic Extensor Carpi Ulnaris Tendon Subluxation in a Collegiate Basketball Player: A Case Report. Journal of Athletic Training, 46(5), 574-576. McAuliffe, J. (2010). Tendon Disorders of the Hand and Wrist. Journal of Hand Surgery, 35A, 846-853.
Ruland, R., Hogan, C. (2008). The ECU Synergy Test: An Aid to Diagnose ECU Tendonitis. Journal of Hand Surgery, 33A, 1777-1782.
Shin, A., Deitch, M., Sachar, K., Boyer, M. (2004). Ulnar-sided Wrist Pain: Diagnosis and Treatment. The Journal of Bone & Joint
Surgery, 86A(7), 1560-1574.
Montalvan, B., Parier, J., Brasseur, J., Le Viet, D., Drape, J. (2006). Extensor carpi ulnaris injuries in tennis players: a study of 28 cases. British Journal of Sports Medicine, 40, 424-429.
MacLennan, A., Nemechek, N., Waitayawinyu, T., Trumble, T. (2008). Diagnosis and Anatomic Reconstruction of Extensor Carpi Ulnaris Subluxation. Journal of Hand Surgery, 33A, 59-64.
Sachar, K. (2012). Ulnar-sided Wrist Pain: Evaluation and Treatment of Triangular Fibrocartilage Complex Tears, Ulnocarpal Impaction Syndrome, and Lunotriquetral Ligament Tears. Journal of Hand Surgery, 37A, 1489-1500.
Huang, J., Hanel, D. (2012). Anatomy and Biomechanics of the Distal Radioulnar Joint. Hand Clinics, 28, 157-163. Young, D., Papp, S., Giachino, A. (2010). Physical Examination of the Wrist. Hand Clinics, 26, 21-36.
Mark, H. (2009). MRI Web Clinic: Extensor Carpi Ulnaris Subsheath Injury. Retrieved from http://www.radsource.us/clinic/0902
Linscheid, R.L. (1998). Disorders of the Distal Radioulnar Joint. In W.P. Cooney, R.L. Linscheid, & J.H. Dobyns (Eds.), The Wrist
Diagnosis and Operative Treatment (Vol. 2, pp. 819-868). St Louis, Missouri: Mosby.
Topper, S.M., Wood, M.B., Cooney, W.P. (1998). Athletic Injuries of the Wrist. In W.P. Cooney, R.L. Linscheid, & J.H. Dobyns (Eds.),
The Wrist Diagnosis and Operative Treatment (Vol. 2, pp. 1031-1074). St Louis, Missouri: Mosby.
Rosenthal, E.A. (1995). The Extensor Tendons: Anatomy and Management. In J.M. Hunter, E.J. Mackin, & A.D. Callahan (Eds.), Rehabilitation of the Hand: Surgery and Therapy (4th ed., pp. 519-564). St Louis, Missouri: Mosby.
