normal  medium  large

CUBITAL TUNNEL SYNDROME

Introduction

Cubital tunnel syndrome is an upper extremity compression neuropathy represented by entrapment of the ulnar nerve at the level of the elbow. Initially, symptoms include pain in the medial aspect of the elbow and pain and paresthesias in the ring and small fingers. Patients complain of numbness partiularly in their little finger.  As the disease progresses, patients become increasingly clumsy and weak, with eventual constant numbness and atrophy of the unlnar intrinsic muscles of the hand. Cubital tunnel syndrome is the second most common compression neuropathy of the upper extremity after carpal tunnel syndrome.

Related Anatomy*

  • Medial epicondyle
  • Anconeus Epitrochlearis
  • Olecranon
  • Cubital tunnel retinaculum
  • Arcade of Struthers
  • Arcuate ligament
  • Medial collateral ligament
  • Osborne fascia
  • Proximal flexor profundus arch
  • Ulnar nerve

* See labeled mages below.

Incidence and Related Conditions

  • Potential etiologies: repetitive use of vibrating tools, playing musical instruments, tourniquet use, intra-operative malpositioning, cubitus varus and valgus deformity, adhesions, burns and heterotopic ossification, space-occupying lesions, osteoarthritis, excessive pressure on the posterior medial elbow and/or excessive hyperflexion posturing of the elbow.

Differential Diagnosis

  • C8 or T1 radiculopathy
  • Thoracic outlet syndrome
  • Pancoast tumor
  • Double crush syndrome
  • Distal ulnar tunnel syndrome (ulnar entrapment in Guyon's canal)
  • Golfer's Elbow (Medial epicondylitis)
Clinical Presentation Photos and Related Diagrams
  • Cubital Tunnel Syndrome landmarks
    Cubital Tunnel Syndrome land marks (Hover over right edge to see more images)
  • Cubital Tunnel Syndrome Anatomic Relations-Ulnar Nerve Under fascia below epicondyle and posterior to intramuscular septum edge
    Cubital Tunnel Syndrome Anatomic Relations-Ulnar Nerve Under fascia below epicondyle and posterior to intramuscular septum edge
Symptoms
Numbness (aresthesia) in 4th and 5th fingers
Pain - medial elbow area, ulnar hand and 4th and 5th fingers
Night pain
Clumsiness
Hand weakness
Muscle atrophy in the hand
Numbness on dorsal ulnar aspect of the hand
Painful clicking at the olecranon groove (ulnar nerve subluxation)
Typical History

Most patients will first present with sensory loss and pain in the little and ring fingers. Sometimes, patients have a history of trauma to the medial side of the elbow. Occasionally, patients will complain of clicking on the medial side of the elbow caused by subluxation of the ulnar nerve over the medial epicondyle. Over time, patients will report problems with grasping objects, feeling clumsy and marked weakness. Symptoms are exacerbated by elbow flexion, resting the elbow on hard surfaces, hyperflexion elbow exercises and shoulder abduction.

Positive Tests, Exams or Signs
Cross Finger Test
Duchenne's Sign (Ulnar Clawing)
Froment's Sign (Bunnell's "O" or Newspaper Sign)
Masse's Sign (Ulnar)
Muscle Test and Tendon Exam: Flexor Carpi Ulnaris (FCU)
Muscle Test and Tendon Exam: Flexor Digitorum Profundus (FDP)
Muscle Test: First Dorsal Interosseous (FDI) [Ulnar Intrinsics]
Muscle Test: Hypothenars [Ulnar Intrinsics]
Sensory Exam by Nerve
Tinel's Sign: Ulnar Nerve (Guyon's)
Tinel's Sign: Ulnar Nerve (Elbow)
Ulnar Intrinsic Atrophy
Ulnar Nerve Elbow Flexion Test
Ulnar Nerve Subluxation
Muscle Test and Tendon Exam: Flexor Digitorum Sublimis (FDS)
Grip Strength
Work-up Options
Electrophysiological testing - EMG/NCV
Magnetic resonance imaging - MRI without contrast
Radiology studies - X-ray
Images (X-Ray, MRI, etc.)
  • Technique for taking a cubital tunnel view.(Hover over right edge to see more images)
    Technique for taking a cubital tunnel view.(Hover over right edge to see more images)
  • Cubital Tunnel view with no arthritis. 1.Cubital tunnel (Olecranon Grove); 2.Olecranon; 3.Proximal Radius; 4.Distal Humerus
    Cubital Tunnel view with no arthritis. 1.Cubital tunnel (Olecranon Grove); 2.Olecranon; 3.Proximal Radius; 4.Distal Humerus
  • Cubital Tunnel view with arthritis.1.Cubital tunnel (Olecranon Grove); 2.Olecranon; 3.Proximal Radius; 4.Distal Humerus Arrow - osteophyte compressing ulnar nerve.
    Cubital Tunnel view with arthritis.1.Cubital tunnel (Olecranon Grove); 2.Olecranon; 3.Proximal Radius; 4.Distal Humerus. Arrow - osteophyte compressing ulnar nerve.
  • Elbow MRI Cross Section - Note medial posterior position of the Ulnar Nerve
    Elbow MRI Cross Section - Note medial posterior position of the Ulnar Nerve
Treatment Options
Conservative: 
  • In patients with early ulnar nerve compression:
    • Avoid maximum elbow flexion
    • Avoid resting elbow on hard surfaces
    • Avoid repetitive hyperflexion elbow exercises
    • Non-steroidal anti-inflamatory drugs (NSAIDs)
Operative: 
  • After symptoms progress and/or become constant:
    • In situ decompression of the ulnar nerve (currently favored procedure for non-subluxating compressed ulnar nerve
    • Transposition (subcutaneous, intramuscular, submuscular) of the ulnar nerve
    • Medial epicondylectomy
Treatment Photos and Diagrams
  • Cubital Tunnel-single arrow Osborne's ligament & double arrow ancoeus epitrochlearis muscle (Hover over right edge to see more images)
    Cubital Tunnel-single arrow Osborne's ligament & double arrow ancoeus epitrochlearis muscle (Hover over right edge to see more images)
  • Cubital Tunnel Syndrome- Note edge of intramuscular Septum. A section of this should be removed when doing anterior transposition of the ulnar nerve. (Hover over right edge to see more images)
    Cubital Tunnel Syndrome- Note edge of intramuscular Septum. A section of this should be removed when doing anterior transposition of the ulnar nerve. (Hover over right edge to see more images)
  • Cubital Tunnel Syndrome: Double arrow was the point of constriction caused by Osborne's ligament and proximal FCU sheath. Proximal swelling consistent with "Pseudoneuroma" of ulnar nerve entrapment.
    Cubital Tunnel Syndrome: Double arrow was the point of constriction cause by Osborne's ligament and proximal FCU sheath. Proximal swelling consistent with "Pseudoneuroma"of ulnar nerve entrapment. (Hover over right edge to see more images)
  • Cubital Tunnel Syndrome - subcutaneous transposition of the ulnar nerve (Hover over right edge to see more images)
    Cubital Tunnel Syndrome - subcutaneous transposition of the ulnar nerve. (Hover over right edge to see more images)
  • Cubital Tunnel Syndrome - Intramuscular Transposition
    Cubital Tunnel Syndrome - Intramuscular Transposition (Hover over right edge to see more images)
  • Cubital Tunnel Syndrome - Submuscular Transposition (Hover over right edge to see more images)
    Cubital Tunnel Syndrome - Submuscular Transposition
  • Ulnar neurolysis using arthroscope
    Ulnar neurolysis using arthroscope (Hover over right edge to see more images)
  • Arthroscopic View of ulnar nerve and fascia
    Arthroscopic View of ulnar nerve and fascia. (Hover over right edge to see more images)
  • Carposcope Ulnar Neurolysis Incision (Hover over right edge to see more images)
    Carposcope Ulnar Neurolysis Incision
  • Carposcope Ulnar Neurolysis Incision open
    Carposcope Ulnar Neurolysis Incision open (Hover over right edge to see more images)
  • Carposcope Ulnar Neurolysis Tools - Guide top left & Scope bottom right
    Carposcope Ulnar Neurolysis Tools - Guide top left & Scope bottom (Hover over right edge to see more images)
  • Carposcope Ulnar Neurolysis- Nerve exposed and scope being placed in subcutaneous tissue superficial to fascia
    Carposcope Ulnar Neurolysis- Nerve exposed and scope being placed in subcutaneous tissue superficial to fascia (Hover over right edge to see more images)
  • Carposcope Ulnar Neurolysis- Dilator separating fascia from underlying ulnar nerve
    Carposcope Ulnar Neurolysis- Dilator separating fascia from underlying ulnar (Hover over right edge to see more images)
  • Carposcope Ulnar Neurolysis- Guide separating fascia from underlying ulnar (Hover over right edge to see more images)
    Carposcope Ulnar Neurolysis- Guide separating fascia from underlying ulnar nerve
  • Carposcope Ulnar Neurolysis-Guide separating fascia from underlying ulnar nerve
    Carposcope Ulnar Neurolysis- Guide separating fascia from underlying ulnar nerve (Hover over right edge to see more images)
  • Carposcope Ulnar Neurolysis- Guide separating fascia from underlying ulnar nerve while forked knife(arrow) begins to cut fascia
    Carposcope Ulnar Neurolysis- Guide separating fascia from underlying ulnar nerve while forked knife(arrow) begins to cut fascia (Hover over right edge to see more images)
  • Carposcope Ulnar Neurolysis- Tortuous nerve
    Carposcope Ulnar Neurolysis- Tortuous nerve (Hover over right edge to see more images)
  • Carposcope Ulnar Neurolysis- Severely constricted ulnar nerve
    Carposcope Ulnar Neurolysis- Severely constricted ulnar nerve before release complete (Hover over right edge to see more images)
  • Carposcope Ulnar Neurolysis- Severely constricted ulnar nerve after release - note residual nerve deformity
    Carposcope Ulnar Neurolysis- Severely constricted ulnar nerve after release - note residual nerve (Hover over right edge to see more images)
  • Carposcope Ulnar Neurolysis- Incision closed
    Carposcope Ulnar Neurolysis- Incision closed
Complications
  • Failure to relieve symptoms
  • Decompression: nerve injury, neuroma
  • Transposition: ischemic neuritis, long-term elbow instability
  • Recurrent ulnar nerve irritation/compression
  • Pain at the osteotomy site
  • Infection
  • Failure to relieve symptoms
  • Medial antebrchial cutaneous nerve injury
  • Ulnar nerve subluxation
Outcomes
  • Conservative: usually only short-term relief of symptoms with subsequent surgery frequently required
  • Operative: satisfactory outcomes have been reported after decompression alone and more extensive procedures
Key Educational Points
  • Cubital tunnel syndrome is the second most common compression neuropathy in the upper extremity.
  • Cubital tunnel syndrome causes numbness in the ring and little fingers.  In chronic cubital tunnel syndrome hand weakness becomes the most troublesome symptom.
  • A rare but important component of the cubital tunnel differential diagnosis is ALS ( Amyotrophic Lateral Sclerosis or Lou Gehrig's Disease). This confusion can occur because 30% of ALS patients present with upper extremity weakness. ALS can be distinquished from Cubital Tunnel Syndrome by the absence of sensory loss, tongue fasciculations, and the involvement of multiple nerves in ALS patients.
  • The most common complication of endoscopic cubital tunnel release is hematoma.
  • To identify weakness of high ulnar innervated muscles compare FDP II & III (median nerve innervated) to FDP IV & V (ulnar nerve innervated) during simultaneous muscle testing of the two pairs.
Practice and CME
References

New articles

  1. Bacle G, Marteau E, Freslon M, et al. Cubital tunnel syndrome: comparative results of a multicenter study of 4 surgical techniques with a mean follow-up of 92 months. Orthop Traumatol Surg Res 2014;100(4Suppl):S205-8.
  2. Noland SS, Fischer LH, Lee GK, et al. Essential hand surgery procedures for mastery by graduating plastic surgery residents: a survey of program directors. Plast Reconstr Surg 2013;132(6):977-84.
  3. Adams S, Isaaca J.  Amyotrophic Lateral Sclerosis. J Hand Surg 2010; 35A:841-845.

Reviews

  1. Rinkel WD, Schreuders TA, Koes BW, Huisstede BM. Current evidence for effectiveness of interventions for cubital tunnel syndrome, radial tunnel syndrome, instability, or bursitis of the elbow: a systematic review. Clin J Pain 2013;29(12):1087-96.
  2. Kroonen LT. Cubital tunnel syndrome. Orthop Clin North Am 2012;43(4):475-86.

Classics

  1. Pechan J, Julis I. The pressure measurement in the ulnar nerve. A contribution to the pathophysiology of the cubital tunnel syndrome. J Biomech 1975;8(1):75-9.
  2. Wadsworth TG, Williams JR. Cubital tunnel external compression syndrome. Br Med J 1973;1(5854):662-6.