Submuscular transposition of the ulnar nerve

Area of Science:

• Orthopedic Surgery
• Neurosurgery
• Hand Surgery

Background:

• Cubital tunnel syndrome, a condition causing ulnar nerve compression at the elbow, can be treated with various surgical techniques.
• Anterior submuscular transposition is a complex procedure, often reserved for cases refractory to less invasive methods or in thin patients where the nerve is superficial.

Purpose of the Study:

• To detail the technical considerations and indications for anterior submuscular transposition using the Learmonth technique for cubital tunnel syndrome.
• To identify common causes of surgical failure and emphasize critical steps for successful ulnar nerve decompression.

Main Methods:

• The Learmonth technique for anterior submuscular transposition is described, highlighting its technical demands.
• Patient selection criteria, including prior surgical failures and patient anatomy, are discussed.
• Key anatomical structures requiring release (arcade of Struthers, arcuate ligament, flexor carpi ulnaris fascia, medial intermuscular septum) are identified.

Main Results:

• Anterior submuscular transposition is technically more challenging than anterior subcutaneous transposition.
• Reoperation for failed anterior submuscular transposition often reveals incomplete decompression of the ulnar nerve.
• Inadequate release of specific anatomical structures is a primary cause of surgical failure.

Conclusions:

• Meticulous release of the arcade of Struthers, arcuate ligament, flexor carpi ulnaris fascia, and medial intermuscular septum is essential for successful cubital tunnel surgery.
• Providing adequate space for the ulnar nerve under the flexor-pronator muscles is critical to prevent re-compression.
• Postoperative range-of-motion and strengthening exercises aid in functional recovery.