Radial nerve compression at the level of the humerus is uncommon and occurs at the spiral groove. The radial nerve has an anatomical course proximal below the lateral intermuscular septum and continues distal between the brachialis and brachioradialis muscles. The entrapment point involves the tendinous lateral intermuscular septum and provocative tests will be positive at this. This is a location that is prone to radial nerve injury during humeral factures. Release of the radial nerve at this level involves dividing the lateral intermuscular septum, while protecting the posterior brachial and antebrachial cutaneous nerves that have an adjacent course to the radial nerve proper. The surgical approach involves dissecting the interval between the brachialis and brachioradialis to identify the radial nerve. In this case, the patient presented with pain originating from the neck that radiated along the course of the posterior division and radial nerve. Her C-spine surgery failed and was referred to our institution. Positive provocative tests included the neck, spiral groove, arcade of Frohse, and radial sensory nerve entrapment. The hierarchical scratch collapse test was used. Radial nerve releases were elected at three sites of entrapment in the upper extremity. This video details the release at the spiral groove.
An incision is made in the interval between the brachialis and brachioradialis muscles on the lateral aspect of the arm.
The incision is closed with absorbable suture and glue. A soft compression dressing is applied. Patients are allowed to weight-bear as tolerated. Assistive devices are offered to patients post-operatively but typically are not needed. Patients are instructed to avoid unnecessary ambulation and elevate the leg as much as possible during the first three weeks post-operatively. This will help limit swelling of the lower extremity and any issues with wound healing. Diabetic and obese patients may require additional interrupted nylon sutures to support their incision. These are removed at two weeks post-operatively. At three weeks post-operatively, patients may be referred to physical therapy to address any issues with edema, scar, ankle ROM, strength and ambulation. At two months post-operatively, they are typically released to all activities.
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Disclosure: No authors have a financial interest in any of the products, devices, or drugs mentioned in this production or publication.