Review Question - QID 217235

This patient presents with lower extremity weakness in knee extension and ankle plantarflexion/dorsiflexion, worsening low back pain, and upper motor neuron signs (hyperreflexia, extensor plantar reflex), which are indicative of spinal cord compression at the L3-L4 level.

Spinal cord compression should be suspected in patients presenting with progressive back pain and lower extremity weakness below the level of the suspected lesion. While some of its symptoms can overlap with those of Guillain-Barre syndrome, spinal cord compression can be differentiated by the finding of upper motor neuron signs, including increased muscle tone, spasticity, hyperactive reflexes, and/or an extensor plantar reflex. Bowel and bladder dysfunction can also be present but these symptoms are typically late findings. Spinal cord compression can be caused by various etiologies, including metastatic disease and epidural abscess. Diagnosis of cord compression can be made with magnetic resonance imaging (MRI) of the spine with and without contrast. Treatment depends on the underlying mechanism but includes glucocorticoids, radiotherapy, and surgery.

Dugas et al. review the presentation of spinal cord compression in non-trauma patients. They found that pain, weakness, and difficulty with ambulation were the most common findings. They recommend consideration of this diagnosis to avoid diagnostic delay.

Incorrect Answers:
Answer 1: Cerebellar ataxia presents with a wide-based, unsteady gait, uncoordinated movements of the extremities, and nystagmus. While cerebellar ataxia can cause frequent falls, this patient’s falls are better attributed to her underlying motor weakness, which is not present in cerebellar ataxia. Additionally, cerebellar ataxia would not account for her back pain or upper motor neuron findings.

Answer 2: Chronic inflammatory demyelinating polyneuropathy is a chronic form of Guillain-Barre syndrome that presents with motor weakness and sensory paresthesias affecting both the proximal and distal limbs. It presents over the course of months, but would not have upper motor neuron signs.

Answer 3: Guillain Barre syndrome, also known as acute inflammatory demyelinating polyneuropathy, typically presents in the days or weeks following a gastrointestinal or genitourinary infection. It presents with ascending paralysis and hyporeflexia/areflexia. In contrast, this patient has hyperreflexia and no signs of an ascending pattern of weakness.

Answer 4: Multiple sclerosis typically presents in younger women with focal neurological deficits, which can include focal motor weakness and optic neuropathy, in a relapsing and remitting pattern. Symptoms are disseminated in both time and space, and lesions can be seen in the brain on MRI. In contrast, this patient’s weakness is localizable to the spinal cord (L3-L4) level as opposed to the brain, and her advanced age makes this much less likely.

Bullet Summary:
While motor weakness is a prominent finding in both spinal cord compression and Guillain-Barre syndrome, the presence of upper motor neuron signs (e.g., hyperreflexia, extensor plantar reflex) is only present in spinal cord compression.