Saltzman EB, Rancy SK, Sneag DB, Feinberg Md JH, Lange DJ, Wolfe SW. Nerve Transfers for Enterovirus D68-Associated Acute Flaccid Myelitis: A Case Series. Pediatr Neurol. 2018 Nov;88:25-30.
Acute flaccid myelitis is associated with enterovirus D68 -induced inflammation and destruction of cervical anterior horn cells. To date, no medical intervention has altered the disease course.
We report two pediatric patients who were treated with nerve transfer in three limbs with sustained upper extremity neuropathy. Postoperative outcomes included muscle strength, graded on the British Medical Research Council (BMRC) scale, range of motion, and electromyography.
Two years postoperatively, Patient 1 had improved elbow flexion to BMRC grade 4+, 125° of flexion, and discrete to decreased motor unit recruitment in targeted muscles. Twenty-one months postoperatively, Patient 2 demonstrated right brachialis flexion to BMRC grade 4+/5 and deltoid firing with simultaneous pectoralis major recruitment, and limited but active flexor digitorum profundus flexion.
Both patients continue to demonstrate functional recovery two years postoperatively. These outcomes suggest a promising reconstructive technique for this emerging and devastating viral endemic.
“We were most surprised that no viable treatment strategy existed to improve the function of patients affected by AFM,” study author Scott Wolfe, MD, told Rare Disease Report®. “We believe that surgical techniques developed for treatment of brachial plexus palsy in children and adults can be used successfully to restore function to paralyzed muscles in affected patients.”
Both of the pediatric patients involved in the case report had demonstrated significant or complete denervation of muscles. The investigators performed nerve transfers in 3 limbs and then measured muscle strength postoperatively in accordance with the British Medical Research Council scale, plus range of motion, and electromyography (EMG) testing.
The first patient, a 12-year-old male from New York State, presented with right greater than upper left extremity weakness. Eventually, he developed bilaterial upper extremity weakness, which progressed to the fingers and neck. He was brought to HSS after 8 months with the disease to undergo surgery, which involved the transfer of donor muscles from other sections of his own body.
After 3 months postop, the patient demonstrated “promising functional returns,” and by 2 years postop, EMG showed full biceps motor unit recruitment. After 35 months, the patient improved to full elbow flexation and shoulder rotation to 135 degrees.
The second patient was a 14-year-old Illinois female who experienced 9 months of upper extremity weakness followed by conjunctivitis and gastroenteritis. She was admitted to intensive care after developing severe neck pain that progressed to flaccid quadriparesis and respiratory failure. She underwent bilateral nerve transfer surgeries using donor muscle tissue from her own body.
After 10 months postop, she regained full right elbow flexation. After 21 months, EMG testing showed discrete recruitment of all 3 deltoid heads that were treated. After 32 months, she achieved near normal right brachialis strength and full recovery in her elbow’s range of motion. The study authors reported she had no functional loss related to the nerve transfers and maintained normal medial nerve function and shoulder adduction.
“With increased numbers of surgically treated patients, we can document outcomes on a larger scale and identify which nerve and tendon transfers offer the best hope for patients with AFM,” Wolfe concluded.