Deep Tendon Reflexes in Transverse Myelitis
Deep tendon reflexes in transverse myelitis are typically hyperreflexic (increased) below the level of the lesion, with possible hyporeflexia (decreased reflexes) at the level of the lesion. This pattern reflects the characteristic pathophysiology of spinal cord inflammation and demyelination 1.
Reflex Patterns in Transverse Myelitis
Below the Lesion Level
- Hyperreflexia (increased reflexes)
- Positive Babinski sign (upgoing toes)
- Clonus may be present
- Increased tone/spasticity
At the Lesion Level
- Hyporeflexia or areflexia (reduced or absent reflexes)
- Flaccid weakness may be present
- Sensory level corresponding to the lesion
Above the Lesion Level
- Normal reflexes
- Preserved motor and sensory function
Clinical Correlation with Lesion Location
The pattern of reflex abnormalities helps localize the lesion:
- Cervical lesions: Hyperreflexia in lower extremities with possible hyporeflexia in upper extremities
- Thoracic lesions: Normal upper extremity reflexes with hyperreflexia in lower extremities
- Lumbar lesions: May present with hyporeflexia or areflexia in lower extremities due to lower motor neuron involvement
Pathophysiological Basis
The hyperreflexia observed below the level of the lesion results from:
- Interruption of descending inhibitory pathways from supraspinal centers
- Release of spinal reflex arcs from higher control
- Development of spasticity due to upper motor neuron damage
The hyporeflexia at the level of the lesion occurs due to:
- Direct damage to reflex arc components within the spinal cord
- Disruption of local neural circuits at the site of inflammation
Diagnostic Significance
Reflex testing is crucial in transverse myelitis as it helps:
- Localize the level of the spinal cord lesion
- Distinguish from other conditions like Guillain-Barré syndrome (which typically presents with hyporeflexia throughout)
- Monitor disease progression and treatment response
Relationship to Other Neurological Findings
The reflex abnormalities in transverse myelitis typically occur alongside:
- Motor weakness (often bilateral and symmetric)
- Sensory level (with pain, temperature, vibration, and proprioception changes)
- Autonomic dysfunction (bladder, bowel, and sexual dysfunction)
Differential Considerations
It's important to note that the reflex pattern in transverse myelitis differs from other demyelinating conditions:
- Multiple sclerosis may have variable reflex findings depending on lesion location 2
- Neuromyelitis optica spectrum disorders often present with longitudinally extensive transverse myelitis with similar reflex patterns but more severe deficits 2
Evolution of Reflexes During Disease Course
During the acute phase, reflexes may initially be decreased due to spinal shock before becoming hyperactive as the condition evolves. The progression of reflex changes can provide valuable information about the disease course and prognosis 1.