A 39-year-old man notices that he sustained a burn to his right hand while cooking, without being aware of it. On further questioning he admits that his grip on the same side has become gradually weaker over several months. On examination he has wasting and weakness of the right intrinsic hand muscles, with occasional fasciculation seen in the abductor pollicis brevis. There is sensory loss to pinprick and temperature over his right arm and trunk in a hemicape distribution. He has a right Horner’s syndrome. His lower limbs have normal power but slightly increased tone, brisk reflexes and extensor plantar responses. The remainder of the examination is normal. Which of the following is the most likely explanation for his symptoms and signs?
2. Meningioma of the cervical cord
3. Neurofibromas in the cervical cord and brachial plexus
4. Primary progressive multiple sclerosis
5. Motor neurone disease
Correct Answer 1
Syringomyelia The combination of gradual spinothalamic sensory loss in the described distribution, Horner’s syndrome, lower motor neurone signs in the upper limb and upper motor neurone signs in the lower limbs, is highly suggestive of syringomyelia, an abnormal cavitation within the central cord. This usually occurs in the cervical region but extend upwards into the brainstem (syringobulbia) or downwards to the thoracic or even lumbar cord. There be associated craniovertebral abnormalities such as a scoliosis or vertebral fusion, and about 90% of patients have a type-1 Chiari malformation (descent of the cerebellar tonsils into the foramen magnum). Treatment is neurosurgical.