II. Epidemiology
- Second most common Compressive Neuropathy of the upper extremity (Carpal Tunnel is most common)
III. Anatomy
- Ulnar Nerve courses superficially and posterior to the medial epicondyle within the Cubital Tunnel
IV. Pathophysiology: Ulnar Nerve Paralysis
- Chronic Trauma to Ulnar Nerve (compression or traction)
- Injury as it passes behind medial epicondyle at elbow (within the Cubital Tunnel)
- Posterior Elbow Dislocation
- Also associated with posterior vascular injuries
V. Associated Conditions
-
Medial Epicondylitis
- Compressive Ulnar Neuropathy occurs in 60% of Medial Epicondylitis patients
- Cubitus Valgus deformity
- Secondary to Growth Plate Fracture or infection
- Results in progressive Ulnar NerveStretching
- Shallow ulnar groove
- Ulnar Nerve subluxation in and out of groove
- Rheumatoid Arthritis
- Elbow Fracture and immobilization
- Excessive leaning on elbow
- Increased elbow flexion and extension
VI. Symptoms
- Medial Elbow Pain, Paresthesias or numbness
- Pain radiates from ulnar aspect of the Forearm into the fourth and fifth fingers
- Provocative
- Repetitive elbow flexion (compresses Cubital Tunnel)
- Elbow in full flexion overnight may cause night pain
VII. Signs
- Tapping or pressure over medial epicondyle (Tinel Sign at the elbow)
- Reproduces Paresthesias or numbness along Ulnar Nerve
- Radiation into Forearm and hand
- Evaluate for Ulnar Nerve subluxation
- Palpate the Ulnar Nerve as it courses behind the medial epicondyle
- Determine if the Ulnar Nerve subluxes with elbow flexion and extension
- Weakness or Atrophy suggests moderate to severe injury (or longstanding nerve injury)
- Forearm weakness
- Flexor carpi ulnaris
- Flexor digitorum palmaris
- Hypothenar weakness or atrophy
- Finger and thumb abduction weakness (Intrinsic Muscles of hand weakness)
- Clawhand Deformity (Ulnar Claw, Spinster's Claw)
- Forearm weakness
VIII. Differential Diagnosis
- Ulnar Tunnel (Symptoms isolated to wrist)
- Cervical Radiculopathy (C8)
IX. Diagnostics: Electromyogram (EMG)
- Delayed conduction at elbow
X. Management: Initial conservative management
- Avoid provocative activity
- NSAIDs
- Moist heat
- Protect nerve from pressure (e.g. elbow pads)
- Corticosteroid Injection
- Night Splinting
XI. Management: Surgical Repair
- Indications
- Persistent Cubital Tunnel refractory to conservative management >3-4 months
- Perform early before motor dysfunction
- Technique
- Transfer nerve anterior to medial epicondyle
- Release of constricting bands
- Results in immediate relief of pain
- Sensory recovery delayed
- Motor recovery may be incomplete