Visualization During Endoscopic Versus Open Cubital Tunnel Decompression: A Cadaveric Study.

PURPOSE: To determine the minimum incision size needed using an open cubital tunnel technique to obtain equivalent visualization comparable with an endoscopic technique.

METHODS: Visualization was assessed in 10 fresh-frozen cadavers with a 2-cm incision, using percutaneous needle localization with the endoscopic system. The most proximal and distal extent of the field of view was marked. Next, an open cubital tunnel release was performed on each cadaver specimen. The incision size was increased incrementally, and the most proximal and distal extents of visualization were recorded for each incision size. The mean visualization distance and standard deviation for each incisional length were calculated.

RESULTS: The mean proximal field of view with the endoscopic technique was 8.1 cm. The mean distal field of view was 8.3 cm. Using the open technique, a 2-cm incision allowed 5.9 cm visualization proximally and 5.2 cm distally, which was significantly less than the endoscopic view. A 4-cm open incision provided similar visualization as the endoscopic technique. A 6-cm open incision was required to obtain statistically significant improvements in visualization compared with an endoscopic technique.

CONCLUSIONS: A 4-cm open incision allowed visualization of approximately 9 cm proximal and 9 cm distal to the medial epicondyle, which was equivalent to the 2-cm endoscopic technique for cubital tunnel release.

CLINICAL RELEVANCE: Although the endoscopic release allows greater visualization of the ulnar nerve with a smaller incision, it is unclear whether this improvement in visualization improves the surgeon's ability to decompress the ulnar nerve.