Novel Technique for Single-Site, Ultrasound-Guided Release of the Cubital Tunnel: An Anatomic Feasibility Study

Hypothesis: Sonography is an effective tool for diagnosing cubital tunnel syndrome. Space occupying visualization, cross sectional area analyzation, and edema can all be assessed in the ulnar nerve. Sonography is utilized currently for minimally invasive approaches to carpal tunnel syndrome and thus is of interest for application in minimally invasive cubital tunnel decompressions. This study explores an in-office alternative to an open surgical procedure through employing the Sonex UltraGuideCTR™ carpal tunnel release system bidirectionally at a single incision site at the level of the cubital tunnel. Methods: We postulate an alternative approach for cubital tunnel decompression via a minimally invasive surgical intervention. Utilizing the Sonex UltraGuideCTR™ as the incising instrument, dissections were performed on three cadaveric arms under live ultrasonographics. The Sonex UltraGuideCTR™ was specifically chosen due to its inherent ability to avoid unintentional soft tissue damage and iatrogenic nerve injury via a retractable blade and inflatable balloons respectively. The cadaveric operations rigidly simulated a surgical operation in regards to time, technique, and care of dissection. Confirmation of fascial release was achieved post-operatively via an open dissection. Results: Use of real-time sonography offered the surgeon a unique vantage point to establish proper alignment of the device and to provide confidence throughout the release. In all three specimens, complete release of the deep and superficial fascia of the flexor carpi ulnaris was observed. Fascial split was associated with longitudinal split of the muscle fibers on either side of the release. There was no identified injury to any motor branches supplying the flexor carpi ulnaris muscle. Proximally, the nerve was noted to be completely decompressed in its course as well. There was no identifiable subluxation of the nerve with ranging of the elbow. The first release was completed in 14 minutes; the second release in 10 minutes; and the final release was completed in 7 minutes. Conclusion: Access to operating theaters is increasingly limited, and the ensuing exigencies of the patient population for in-office procedures has become a driver for novel interventions. Modeled from currently accepted minimally invasive management of carpal tunnel syndrome, the Sonex UltraGuideCTR™ device was utilized in similar fashion at the level of the cubital tunnel to successfully decompress the ulnar nerve. In response to meeting the rising need for patient access to surgical intervention outside of the operating room, such novel approaches are becoming increasingly necessary and embolden surgeons and device developers alike to expand their horizons.