The McGowan classification was published in 1950[^1] and is used to classify lesions of the Ulnar nerve into three different grades.
Classification
McGowan Grade | Description |
Grade I | Minimal lesion without objective motor deficits. Paresthesias in the distribution of the ulnar nerve. |
Grade II | Intermediate lesion with incomplete weakness of the interosseous muscles. Hypoesthesia in the distribution of the ulnar nerve may occur. Sweating is preserved. |
Grade III | Severe sensorimotor deficit with complete paralysis of one or more muscles innervated by the ulnar nerve. |