Spine

Abstract

51-Year-old male presents to the office with a 2-month history of severe pain originating in his low back. The pain travels down the posterior aspect of his thigh down into the bottom of his foot. The pain is associated with subjective numbness and a sensation of pins and needles across the lateral aspect of his foot. He notes weakness in his “calf” muscle. Conservative measures initiated by his primary care physician 6 weeks ago included nonsteroidal anti-inflammatories, a Medrol dose pack, and physical therapy. Lumbar epidural injections performed by a physiatrist 2 weeks ago failed to provide any relief of his symptoms. Physical examination of the patient showed subjective numbness along the plantar aspect of the foot, 4/5 strength in ankle plantar flexion, and an inability to heel raise ten times on the right. A MRI of the lumbar spine revealed a herniated intervertebral disc at the L5–S1 level, causing severe right-sided S1 nerve root compression (Fig. 1.1). The patient underwent a right-sided L5–S1 microdiscectomy, and recovered 5/5 strength in ankle plantar flexion with complete resolution of his pain by 2 weeks postoperatively.

Questions

Which of the following statements is true?

• (a) Cervical nerve roots come off the spinal cord below their corresponding pedicle, and lumbar nerve roots come off above their corresponding pedicle.

• (b) Both cervical and lumbar nerve roots come off above their corresponding pedicle.

• (c) Cervical nerve roots come off the spinal cord above their corresponding pedicle, and lumbar nerve roots come off below their corresponding pedicle.

• (d) Both cervical and lumbar nerve roots come off below their corresponding pedicle.

At which level is the conus medullaris typically found?

• (a) Foramen magnum

• (b) C7–T1

• (c) T7–T10

• (d) L1–L2

• (e) L5–S1

The sensation of the abdomen and back at the level of the umbilicus corresponds to what thoracic level?

• (a) T1

• (b) T10

• (c) T12

• (d) T4

• (e) T8

What superficial anterior landmark can be palpated to approximate the level of C4?

• (a) Thyroid cartilage

• (b) Hyoid bone

• (c) Sternocleidomastoid muscle

• (d) Carotid tubercle

• (e) Carotid pulse

A right-sided far lateral disc herniation at L4–5 would be expected to produce what signs and symptoms?

• (a) Right-sided quadriceps weakness, pain extending down to the top of the foot.

• (b) Left-sided foot drop, left-sided numbness over the dorsum of the foot.

• (c) Bilateral hallux extension weakness, numbness at the right foot first webspace.

• (d) Right-sided ankle dorsiflexion weakness, pain down into the front of the leg.

• (e) Right-sided hip extension weakness, numbness over the lateral aspect of the leg.