Neurological symptoms

Motor disorders and cerebellar impairments

Psychogenic or hysterical motor disorders are distinguished by bizarre gaits — for example, a "scythe-weaving" pattern — as well as the demonstration of deficits to others in the complete absence of objective neurological symptoms in the medical history.

Cerebellar ataxia occurs due to dysfunction of the cerebellum itself or its associated pathways. In pathology of the cerebellar hemisphere, motor coordination disorders occur strictly on the homolateral side. Deviation of the trunk toward the affected hemisphere is characteristic. Isolated lesion of the cerebellar vermis leads to truncal ataxia with balance and gait disorders, nystagmus, and dysarthria, but without limb ataxia.

Peripheral nerve lesions and polyneuropathies

Lesions of the peripheral nerves of the upper extremities have a characteristic clinical picture:

• Radial nerve — "wrist drop" syndrome.
• Ulnar nerve (often due to prolonged compression or trauma) — paresthesias, hypothenar muscle atrophy and m. adductor pollicis, as well as the formation of a "claw hand".
• Median nerve — "hand of benediction" sign.
• Combined damage to the median and ulnar nerves — "ape hand" syndrome.

Polyneuropathies represent diffuse fiber lesions classified by histological criteria (axonal, demyelinating), nature (sensory, motor, autonomic), and distribution. Polyneuritis has an exclusively infectious and inflammatory origin.

Clinical syndromes of spinal cord pathology

Spinal cord tumors cause slowly progressive disorders whose structure consists of three main components:

1. Radicular syndrome — accompanied by pain that worsens when lying down and during coughing, as well as local tenderness upon percussion of the spinous processes.
2. Segmental disorders — peripheral pareses and autonomic disorders at the level of the tumor.
3. Tract disorders — central pareses and sensory disturbances below the lesion focus.

Lateral location of the neoplasm leads to Brown-Séquard syndrome: ipsilateral radicular disorders and central paresis develop, while pain and temperature sensitivity are impaired contralaterally. At the level of the conus medullaris, the anogenital zone and pelvic functions are affected, while lesions of the cauda equina result in pain and peripheral paresis of the feet.

Class and exam questions

What else to study on this topic

• Diagnostic features of parainfectious myelitis using MRI and CSF analysis
• Differential diagnosis of spinal cord tumors and multiple sclerosis
• Topical features of tract disorders in the cervical, thoracic, and lumbar regions
• Classification of polyneuropathies by histological and clinical criteria
• Clinical manifestations of conus medullaris and cauda equina lesions

Other topics in the section "DeMyer's The Neurologic Examination" / "Duus' Topical Diagnosis in Neurology"

Prepared by WhiteCoat Pro faculty in accordance with the medical school curriculum. For educational purposes only.