A new method to quantify innervation of the ulnar intrinsic hand muscles by the anterior interosseous nerve in Martin-Gruber anastomosis and nerve transfer surgery.

In comparison to previously described techniques, the digital subtraction method has a number of practical advantages. It uses conventional nerve conduction study setup, and the added step of digital alignment and subtraction can be done through commonly available software. With the increasing use of nerve transfer surgery in severe high ulnar nerve injury, this could be a useful method to identify the presence of MGA prior to surgery and for evaluating nerve recovery following surgery.