What is the treatment for an ulnar nerve dislocated out of the cubital tunnel with paresthesia along the ulnar distribution in the hand?

Treatment of Dislocated Ulnar Nerve with Paresthesia

For a dislocated ulnar nerve out of the cubital tunnel with paresthesia along the ulnar distribution in the hand, surgical intervention is recommended when conservative treatment fails to relieve symptoms, especially in cases with persistent neurological deficits. 1

Initial Assessment and Conservative Management

• Initial evaluation should include radiographs of the elbow to rule out bony abnormalities or joint pathology that may contribute to nerve compression 2
• Conservative treatment should be attempted first in mild to moderate cases (McGowan grade 1-2) and includes:
  • Activity modification to avoid repetitive elbow flexion and direct pressure on the ulnar nerve 1
  • Night splinting in neutral position to prevent prolonged elbow flexion during sleep 3
  • Ulnar nerve gliding exercises performed by an occupational therapist to improve nerve mobility 4
  • Patient education regarding ergonomic modifications and postural adaptations 5

Nerve Gliding Exercise Protocol

• Ulnar nerve gliding exercises have shown promising results in moderate cubital tunnel syndrome with significant improvement in:
  • Decreased paresthesia severity
  • Improved grip and pinch strength
  • Better sensory function on Semmes-Weinstein monofilament testing
  • Improved nerve conduction velocities 4
• The recommended protocol includes repetitive passive wrist movement at maximal elbow flexion position for 20 minutes, twice weekly, for an average treatment period of 5-6 months 4, 5

Indications for Surgical Management

Surgical intervention should be pursued when:

• Conservative treatment fails after 3-6 months 3
• Patient presents with:
  • Motor weakness
  • Muscle atrophy
  • Fixed sensory changes
  • Progressive neurological deficits 1, 3
• Painful or symptomatic recurrent dislocation of the ulnar nerve 3

Surgical Options

1. Simple in-situ decompression (recommended as first-line surgical approach):

   • Involves releasing the compressive structures around the ulnar nerve without transposition
   • Can be performed through open or endoscopic techniques under local anesthesia
   • Decompression should extend at least 5-6 cm distal to the medial epicondyle 3
   • Preferred for primary cubital tunnel syndrome with dislocated nerve 6, 3

2. Anterior transposition (for specific cases):

   • Subcutaneous anterior transposition: Indicated when ulnar nerve dislocation is painful or when the nerve "snaps" over the medial epicondyle 3
   • Submuscular transposition: Preferred in cases with significant scarring as it provides a healthy vascular bed and soft tissue protection 3
   • Indicated in cases with severe bone or tissue changes of the elbow (especially with cubitus valgus) 3

3. Medial epicondylectomy (less common approach):

   • Not as commonly performed, especially in some countries 3
   • May be considered in specific cases where other approaches are not suitable

Potential Complications and Considerations

• Risks of transposition include compromise in blood flow to the nerve and potential kinking if inadequate mobilization is performed 3
• Recurrence of compression may occur and require revision surgery 3
• Proper positioning during surgery is critical to prevent additional nerve injury:
  • The forearm should be positioned to decrease pressure on the postcondylar groove of the humerus 2
  • Either supination or neutral forearm position is recommended 2
  • Excessive elbow flexion (>90°) should be avoided as it may increase risk of ulnar neuropathy 2

Follow-up and Monitoring

• Regular assessment of motor and sensory function in the ulnar nerve distribution
• Monitoring for improvement in paresthesia, grip strength, and functional status
• Long-term follow-up is essential as recovery may continue for several months after treatment 4, 5