Hirayama disease causing hand tremor on neck flexion

Area of Science:

• Neurology
• Neurosurgery
• Radiology

Background:

• Hirayama disease is a rare, self-limiting, juvenile spinal muscular atrophy.
• It typically affects young males, presenting with unilateral upper limb weakness and atrophy.

Observation:

• A 21-year-old male presented with progressive right-hand intrinsic muscle wasting and tremor exacerbated by neck flexion.
• Cervical spine MRI revealed cord compression and venous engorgement during neck flexion, not apparent in neutral position.

Findings:

• Dynamic cervical spine MRI confirmed anterior displacement and flattening of the cervical cord with posterior epidural space widening.
• Engorgement of the epidural venous plexus was noted during neck flexion, characteristic of Hirayama disease.

Implications:

• Early diagnosis of Hirayama disease through dynamic MRI is crucial for effective management.
• Conservative treatment, including neck collars and physiotherapy, can stabilize or improve symptoms, preventing further neurological deficit.