A dynamic anatomical study of ulnar nerve motion after anterior transposition for cubital tunnel syndrome.

Cubital tunnel syndrome is the second most commonly encountered compression neuropathy of the upper limb. Multiple techniques for surgical management have been proposed but no universally accepted algorithm for management exists. Six cadaveric upper limbs underwent ulnar nerve decompression and anterior transposition into subcutaneous and then submuscular positions. After marking nerves with tungsten, radiological examination of nerve motion was performed and nerve angulations were measured in the region of the flexor carpi ulnaris (FCU) origin. Comparison of ulnar nerves in each position revealed statistically significant greater angulation after subcutaneous transposition than after submuscular transposition with the elbow held in full flexion. This point of angulation may act as a secondary point of compression or as a focus for neuritis and scar formation. This finding can contribute to the understanding of why differing outcomes may be observed after different forms of anterior transposition.