From the Research
Ulnar nerve transposition typically allows for 1.8 ± 0.6 cm of additional nerve length, as determined by a study on the vascularized ulnar nerve and its blood supply for cubital tunnel syndrome at the elbow region 1. This length gain is achieved by moving the nerve from its original position behind the medial epicondyle to a new anterior position, effectively shortening the path the nerve must travel. The exact amount of length gained varies depending on the specific surgical technique used (subcutaneous, intramuscular, or submuscular transposition) and individual patient anatomy. Some key points to consider when evaluating the effectiveness of ulnar nerve transposition include:
- The importance of reducing tension on the nerve, which is crucial for proper nerve function and healing
- The need for surgeons to avoid creating new compression points or kinking of the nerve when securing it in its new position, as this could negate the benefits of the additional length gained through transposition
- The potential for anatomical structures, such as the common aponeurosis of the humeral head of the flexor carpi ulnaris (FCU) and flexor digitorum superficialis (FDS) muscles, to become new sources of nerve compression after anterior transposition 2
- The average distance that the vascularized ulnar nerve can be moved to the subcutaneous tissue under tension-free conditions, which can be used as a reference value during the treatment of cubital tunnel syndrome with anterior transposition of the vascularized ulnar nerve 1 It is also worth noting that while some studies have reported varying degrees of length gain with ulnar nerve transposition, the most recent and highest quality study on the topic provides the most reliable estimate of the average length gain achievable with this procedure 1.