Rehabilitation challenges in a polytrauma patient with discordant neurological findings: coexistence of traumatic brachial plexus injury and bilateral ankle clonus – a case report

Abstract

Traumatic brachial plexus injury (BPI) typically produces lower motor neuron (LMN) findings, whereas exaggerated reflexes and ankle clonus suggest upper motor neuron (UMN) pathway involvement. Their coexistence following polytrauma presents a diagnostic and rehabilitation challenge. A 23-year-old man sustained a road traffic accident while riding a two-wheeler, resulting in severe left upper-limb weakness and a comminuted distal femur fracture. Following open reduction and internal fixation, he was referred for rehabilitation. Examination revealed marked hypotonia, with muscle power of 1/5 in the left shoulder and elbow and 2/5 in the finger flexors and abductors. Left biceps and triceps reflexes were absent, while sensation was impaired in the C5 and C6 dermatomes. Bilateral Hoffmann signs, brisk knee jerks, and sustained ankle clonus were present. There was no definite sensory level, and bladder and bowel functions were preserved. Nerve conduction studies and electromyography suggested left brachial plexopathy with axonal involvement. Computed tomography of the brain and spine showed no acute abnormality. Spinal MRI was not obtained because of concerns regarding the femoral fixation implants. A multidisciplinary rehabilitation programme included positioning, splinting, passive mobilisation, electrical stimulation, lower-limb exercises, progressive mobilisation, transfer training, and functional retraining. Functional Independence Measure score improved from 45/126 at admission to 90/126 after one month. Upper-limb weakness persisted, while ankle clonus decreased on serial examination. This case highlights the importance of repeated neurological assessment and individualized multidisciplinary rehabilitation when peripheral and possible central motor pathway findings coexist following polytrauma.