Recovery of an injured corticofugal tract from the supplementary motor area in a patient with traumatic brain injury

RATIONALE We report on a patient with traumatic brain injury who showed motor recovery concurrent with recovery of injured corticofugal tracts (CFTs), diagnosed by diffusion tensor tractography (DTT). PATIENT CONCERNS Four weeks after onset, when the patient started rehabilitation, he showed severe weakness of both upper and lower extremities [Motricity Index (MI, full score: 100/100): 9/30]. DIAGNOSES A 29-year-old male patient underwent conservative management for traumatic hemorrhages in both frontal lobes and right thalamus resulting from a car accident. INTERVENTIONS The patient participated in a comprehensive rehabilitative management program, including movement therapy, dopaminergic drugs for improvement of apraxia (pramipexole: 2.5mg, amantadine: 300mg, ropinirole: 0.75 mg, and levodopa: 500mg), and neuromuscular electrical stimulation therapy of the right elbow extensors, finger extensors, both knee extensors, and ankle dorsiflexors. OUTCOMES After 2 months' intensive rehabilitation, his motor weakness rapidly recovered to the point that he was able to move all 4 extremities against some resistance (MI: 75/75). The right supplementary motor area (SMA)-CFT showed narrowing and partial tearing in the upper portion on 1-month DTT, and became thicker on 3-month DTT. Compared to the 12 normal control subjects, the fractional anisotropy (FA) values of the right corticospinal tract and both dorsal premotor cortex-CFT were more than 1 standard deviation lower than those of normal control subjects on both 1- and 3-month DTTs. LESSONS Although the tract volume of the right SMA-CFT was more than 1 standard deviation lower than normal control subjects on 1-month DTT, it increased to within 1 standard deviation on 3-month DTT. Recovery of the injured SMA-CFT concurrent with motor recovery was demonstrated in a patient with traumatic brain injury.