A 58-year-old man presented with back pain of two months’ duration.
The back pain began after lifting heavy packages at the hotel
where he worked as a porter. He had visited another doctor one month
earlier for back pain, and naproxen was prescribed with some benefit.
Over the next two weeks, he noted difficulty walking due to weakness
in his legs. He delayed coming to the hospital until a friend was
able to drive him to the city from the upstate community in which
He had no prior history of low back pain. Five years earlier,
he had a positive PPD skin test for tuberculosis, but was not treated.
There was no history of intravenous drug use. He had no prior medical
On examination, he was a slim but
well-developed male in no distress (Figure 1). He was afebrile.
Cardiac, pulmonary, and abdominal examinations were normal. On rectal
examination, he had normal sphincter tone, his prostate was normal,
and stool did not have occult blood.
The patient had to use his hand to assist hip flexion.
He could support his weight standing, but needed to hold on to a
support while walking.
On neurologic examination, there was mild wasting of his thigh
muscles. Muscle strength testing showed 4+/5
hip flexion, 5−/5 knee flexion and extension,
and 5/5 ankle plantar and dorsiflexion. On sensory examination,
there was diminished light touch and pin prick below the waist and
umbilicus. Position sense of his toes was normal. His reflexes were +3
patella and ankle bilaterally without clonus. Upper extremity reflexes
were +2 bilaterally. His plantar reflex was flexion
on the left, and withdrawal (or extension) on the right.
Chest, thoracic, and lumbar spine radiographs were obtained (Figures 2 and 3).
Thoracic spine radiographs.
This patient had bilateral lower extremity motor and sensory
deficits indicative of a neurological lesion localized to the spinal
cord. The brisk lower extremity reflexes reflect a spinal cord lesion (upper
motor neuron), as opposed to a lumbar radicular or cauda equina
syndrome (lower motor neuron). The loss of sensation below the T10–T11
dermatome suggests a lesion at this level of the spinal cord. (The
associated vertebral lesion is located one or two levels above the
spinal cord level).
The main diagnostic considerations ...