6. Spine MCQs

A 19-year-old collegiate baseball pitcher undergoes reconstruction of the ulnar collateral ligament (UCL) of the elbow. Which bundle of the UCL is considered the primary restraint to valgus stress between 30 and 120 degrees of elbow flexion?

When placing a pedicle screw at the L4 vertebral level, the ideal anatomical starting point is identified at the intersection of a line bisecting the transverse process and a vertical line plumb with which of the following structures?

During a multi-level anterior cervical discectomy and fusion (ACDF), lateral dissection places the vertebral artery at risk. In normal cervical anatomy, the vertebral artery typically enters the foramen transversarium at which cervical vertebral level?

During a right-sided anterior cervical discectomy and fusion (ACDF) at C5-C6, the surgeon carefully mobilizes the visceral structures to avoid nerve injury. Which of the following anatomic characteristics makes the recurrent laryngeal nerve more susceptible to injury on the right compared to the left?

During a posterior lumbar interbody fusion at L4-L5, the surgeon places pedicle screws into the L4 vertebrae. To avoid radicular injury, the surgeon must remember that the exiting L4 nerve root passes in which relationship to the L4 pedicle?

Transforaminal endoscopic lumbar discectomy utilizes the Triangle of Kambin for safe access to the disc space. Which of the following structures forms the anterior boundary (hypotenuse) of this anatomic triangle?

A spine surgeon is performing a lateral transpsoas approach (LLIF/XLIF) to the lumbar spine at the L4-L5 level. To minimize the risk of iatrogenic injury to the lumbar plexus, the surgeon relies on anatomic safe zones. At the L4-L5 disc space, where is the lumbar plexus most commonly located within the substance of the psoas major muscle?

A 45-year-old man presents with severe right leg pain radiating to the anterior thigh. Magnetic resonance imaging reveals a far-lateral (extraforaminal) disc herniation at the L3-L4 level. Which nerve root is most likely compressed, and what clinical examination finding is expected?

A 45-year-old male presents with severe right anterior thigh pain and new-onset weakness in knee extension. MRI of the lumbar spine reveals a far lateral (extraforaminal) disc herniation at the L3-L4 level. Which nerve root is most likely compressed in this specific anatomical zone?

A 45-year-old patient presents with neck pain and occipital headaches after a motor vehicle collision. Flexion-extension radiographs of the cervical spine demonstrate an atlantodental interval (ADI) of 4 mm. An MRI is obtained to evaluate the ligamentous structures. The alar ligaments primarily prevent which of the following movements?

A 60-year-old patient is undergoing a minimally invasive L4-L5 transforaminal lumbar interbody fusion (TLIF). To avoid injury to the exiting nerve root during facetectomy and disc preparation, the surgeon must be aware of its exact anatomical relationship to the pedicles. Which nerve root exits through the L4-L5 intervertebral foramen, and what is its anatomic relationship to the L4 pedicle?

A spine surgeon is placing pedicle screws in the lumbar spine from L1 to L5. Which of the following describes the normal morphometric progression of the lumbar pedicles as one moves caudally from L1 to L5?

A 45-year-old female with long-standing rheumatoid arthritis presents with suboccipital neck pain and new-onset clumsiness in her hands. Dynamic cervical radiographs and a subsequent MRI reveal marked atlantoaxial instability and pannus formation. In evaluating the stability of the atlantoaxial joint, the alar ligaments serve as the primary restraints to which specific motion?

A 52-year-old male is scheduled for an anterior lumbar interbody fusion (ALIF) at the L4-L5 and L5-S1 levels. During the preoperative consent process, the surgeon discusses the risks of the procedure, specifically highlighting the potential for injury to a neural plexus that lies directly anterior to the L5-S1 intervertebral disc space. Iatrogenic injury to this structure will most likely result in which of the following complications?

A spine surgeon is placing L4 pedicle screws using a freehand technique. According to standard anatomical landmarks (the intersection technique), what is the optimal starting point for the L4 pedicle screw?

A 55-year-old man undergoes a lateral transpsoas approach to the lumbar spine for interbody fusion at L4-L5. Postoperatively, he complains of profound weakness in extending the knee and numbness over the anteromedial thigh and medial calf. The injured nerve is formed by the ventral rami of which nerve roots, and where does it typically emerge in relation to the psoas major muscle?

A spine surgeon is performing an anterior cervical discectomy and fusion (ACDF) for C5-C6 myelopathy.

When aggressively decompressing the lateral aspect of the uncovertebral joint, there is a distinct risk of iatrogenic injury to the vertebral artery. Ascending from the subclavian artery, the vertebral artery classically first enters the transverse foramen at which cervical level in the vast majority of patients?

A 45-year-old man presents with severe lower back pain radiating down the right leg. Physical examination reveals weakness in right great toe extension (extensor hallucis longus) and diminished sensation over the dorsal first web space. Deep tendon reflexes are symmetrical and intact. An MRI reveals a far-lateral (extraforaminal) disc herniation at the L5-S1 level. Which nerve root is most likely compressed?

A 15-year-old female gymnast complains of persistent, insidious low back pain that is exacerbated by spinal extension maneuvers. Her neurological examination is completely normal. Plain AP and lateral radiographs of the lumbar spine are unremarkable. Which of the following imaging modalities is the most appropriate next step to diagnose an early, radiographically occult active pars interarticularis stress reaction?

A 22-year-old collegiate baseball pitcher reports medial elbow pain during the late cocking and early acceleration phases of throwing. On examination, he has localized tenderness slightly distal to the medial epicondyle and a positive moving valgus stress test. An MRI of the elbow (Figure 8) demonstrates a full-thickness tear of the ulnar collateral ligament (UCL). Which of the following components represents the primary restraint to valgus stress at the elbow between 30 and 120 degrees of flexion?