C A S E O F T H E M O N T H
STRETCH INJURY OF THE BRACHIAL PLEXUS
A 30-year-old man was driving a motorcycle when he swerved to avoid a child who suddenly darted out onto the street. He lost control, causing his motorcycle to crash. He was flung off the bike and thrown to the pavement. He was dazed but did not lose consciousness, and noted that he was unable to move his left arm right after the crash. He was immediately taken to a nearby hospital for treatment.
On examination, he was awake, alert, and able to follow commands. Fortunately, he was wearing a helmet, which may have protected him from head injury. His left arm hung heavily and limply at his side. He was unable to lift up his arm or bend his elbow, but he was able to wiggle his fingers weakly. He also had numbness in his entire left arm. Based on the above findings, the patient was diagnosed to have a left brachial plexus injury. The brachial plexus is a large bundle of nerves arising from the spinal cord and supply the muscles of the arm. A stretch injury of the brachial plexus most likely occurred when the patient hit the pavement after he was thrown off his motorcycle.
MRI of the cervical spine did not show any signs of nerve root avulsion (nerve root separated from the spinal cord). Electrical studies done 3 weeks after the injury showed signs of brachial plexus injury.
He underwent physical therapy and followed up regularly with a peripheral nerve specialist to monitor his clinical condition. His hand function had started to improve 2 weeks after the injury. By 3 months post-injury, his hand and wrist function were almost normal. The numbness in his left arm had also lessened. However, he was still unable to lift up his arm or bend his elbow. Repeat electrical studies showed no improvement in these muscle groups.
Stretch injuries of the brachial plexus are usually treated conservatively at the outset. Spontaneous recovery may still occur and surgery may not be necessary. Surgery is considered if there is no improvement after 3 to 4 months.
The patient underwent surgery for nerve repair. The operation went well and the patient was discharged the following day. It will take time before the effects of the surgery will be seen, because nerves regenerate very slowly. In the meantime, the patient was advised to continue physical therapy after a one-month rest after the surgery.
Six months after the surgery, the patient started to regain movement of his arm. One year later, he was able to lift his arm against mild resistance and bend his elbow. He still had some arm numbness but it was much less compared to before. |
