Menu

Thoracolumbar Spine & Deformity MCQs

Practice Set 30 of 49

This practice set contains high-yield board review questions covering key concepts in Thoracolumbar Spine & Deformity. Each clinical scenario is designed to test your diagnostic and management skills relevant to this subspecialty.

Question 581

Topic: Thoracolumbar Spine & Deformity

A 68-year-old woman with a history of adult degenerative scoliosis presents with a progressive forward-leaning posture. Radiographs show a Sagittal Vertical Axis (SVA) of +12 cm. What is the primary compensatory mechanism utilizing the pelvis to maintain upright posture in this condition?

. Pelvic anteversion (decreased pelvic tilt)
. Pelvic retroversion (increased pelvic tilt)
. Decreased sacral slope with decreased pelvic tilt
. Increased lumbar lordosis
. Increased thoracic kyphosis

Correct Answer & Explanation

. Pelvic anteversion (decreased pelvic tilt)

Explanation

In the setting of positive sagittal imbalance, the body compensates to maintain an upright gaze. The primary pelvic compensatory mechanism is pelvic retroversion, which corresponds to an increased pelvic tilt (PT) and a decreased sacral slope (SS).

Question 582

Topic: Thoracolumbar Spine & Deformity

A patient is evaluated for adult spinal deformity. Radiographic parameters reveal a Pelvic Incidence (PI) of 60 degrees, a Pelvic Tilt (PT) of 30 degrees, and a Sacral Slope (SS) of 30 degrees. Which of the following statements best describes the relationship of these spinopelvic parameters?

. PI = PT - SS
. PT = PI + SS
. SS = PI + PT
. PI = PT + SS
. PT = PI / SS

Correct Answer & Explanation

. PI = PT - SS

Explanation

Pelvic incidence (PI) is a fixed morphologic parameter representing the algebraic sum of the pelvic tilt (PT) and sacral slope (SS). The equation PI = PT + SS is fundamental in understanding spinopelvic alignment and calculating deformity correction targets.

Question 583

Topic: Thoracolumbar Spine & Deformity

In surgical planning for a 65-year-old woman with adult degenerative scoliosis and severe sagittal imbalance, restoring physiological alignment is critical to minimize mechanical failure. Which of the following best represents the ideal relationship between pelvic incidence (PI) and lumbar lordosis (LL) for optimal postoperative sagittal balance?

. LL should be restored to within 10 degrees of the PI
. LL should be precisely half of the PI measurement
. PI should be surgically reduced to match the patient's LL
. Pelvic tilt (PT) should be maximized to compensate for a PI-LL mismatch
. LL should exceed PI by at least 20 degrees

Correct Answer & Explanation

. LL should be restored to within 10 degrees of the PI

Explanation

Optimal sagittal balance in adult spinal deformity surgery is achieved when Lumbar Lordosis (LL) is restored to within 10 degrees of the Pelvic Incidence (PI). Pelvic Incidence is a fixed morphological parameter that cannot be changed surgically, necessitating the appropriate correction of LL to match it.

Question 584

Topic: Thoracolumbar Spine & Deformity

A 35-year-old man falls from a roof and sustains an L1 burst fracture. He is neurologically intact. Which of the following radiographic parameters is the most important determinant for surgical intervention based on the TLICS classification?

. 10% loss of anterior vertebral body height
. 15 degrees of focal kyphosis
. Posterior ligamentous complex (PLC) disruption
. 20% spinal canal compromise
. Presence of a vertical laminar fracture

Correct Answer & Explanation

. 10% loss of anterior vertebral body height

Explanation

In the Thoracolumbar Injury Classification and Severity (TLICS) score, PLC disruption is a critical determinant of instability. A neurologically intact patient with an definitively ruptured PLC is generally recommended for surgical stabilization.

Question 585

Topic: Thoracolumbar Spine & Deformity

When evaluating a patient with adult spinal deformity, which of the following spinopelvic parameters is a fixed morphologic feature of the pelvis that does not change with patient position?

. Pelvic tilt
. Sacral slope
. Pelvic incidence
. Lumbar lordosis
. Sagittal vertical axis

Correct Answer & Explanation

. Pelvic tilt

Explanation

Pelvic incidence is a fixed anatomic parameter unique to each individual and does not change with postural position. It is defined geometrically as the sum of pelvic tilt and sacral slope.

Question 586

Topic: Thoracolumbar Spine & Deformity

A 60-year-old woman presents with lower back pain and left leg pain. Imaging reveals a grade 1 L4-5 degenerative spondylolisthesis. Which of the following is the most significant structural risk factor for the development of degenerative spondylolisthesis?

. Male sex
. Sagittal facet orientation
. Pars interarticularis stress fracture
. Previous lumbar discectomy
. Severe osteoporosis

Correct Answer & Explanation

. Male sex

Explanation

A more sagittal orientation of the facet joints is a strong predisposing factor for the development of degenerative spondylolisthesis, particularly at L4-L5. Female sex and advancing age are also major risk factors.

Question 587

Topic: Thoracolumbar Spine & Deformity

A 25-year-old woman presents to the trauma bay after a high-speed motor vehicle collision where she was wearing only a lap belt. She has a large abdominal ecchymosis. Radiographs reveal a transverse fracture through the pedicles, pars, and vertebral body of L2. What associated injury must be heavily suspected?

. Aortic transection
. Intra-abdominal hollow viscus injury
. Diaphragmatic rupture
. Splenic laceration
. Renal artery thrombosis

Correct Answer & Explanation

. Aortic transection

Explanation

A Chance fracture (flexion-distraction injury) in the setting of a lap-belt mechanism is highly associated with concurrent intra-abdominal hollow viscus injuries (e.g., small bowel rupture), which occur in up to 50% of these cases.

Question 588

Topic: Thoracolumbar Spine & Deformity

Which of the following spinopelvic parameters is a fixed morphological parameter that is NOT altered by patient positioning or spinal alignment changes?

. Pelvic tilt
. Sacral slope
. Pelvic incidence
. Lumbar lordosis
. Sagittal vertical axis

Correct Answer & Explanation

. Pelvic tilt

Explanation

Pelvic incidence (PI) is a fixed anatomical parameter that does not change with positioning. It is the sum of pelvic tilt (PT) and sacral slope (SS), which are both dynamic.

Question 589

Topic: Thoracolumbar Spine & Deformity

A 16-year-old male presents with increasing thoracic kyphosis and mid-back pain. Radiographs reveal anterior wedging of multiple thoracic vertebrae. According to the Sorensen criteria, what specific radiographic finding is required to formally diagnose classic Scheuermann's kyphosis?

. At least 3 consecutive vertebrae with >5 degrees of anterior wedging
. At least 2 consecutive vertebrae with >10 degrees of anterior wedging
. A total structural Cobb angle > 45 degrees with any wedging present
. A kyphosis apex at T10 with at least 1 vertebral wedge > 5 degrees
. The presence of Schmorl's nodes in at least 4 contiguous levels

Correct Answer & Explanation

. At least 3 consecutive vertebrae with >5 degrees of anterior wedging

Explanation

The classic Sorensen criteria for Scheuermann's disease require the presence of at least 3 consecutive thoracic vertebrae demonstrating greater than 5 degrees of anterior wedging each.

Question 590

Topic: Thoracolumbar Spine & Deformity

A 45-year-old construction worker falls 15 feet, sustaining an L1 burst fracture. He is neurologically intact on presentation. According to the Thoracolumbar Injury Classification and Severity (TLICS) score, which of the following radiographic parameters is the strongest indication for operative stabilization over nonoperative brace management?

. 15% loss of anterior vertebral body height
. 10 degrees of focal sagittal kyphosis
. Disruption of the posterior ligamentous complex
. 20% central canal compromise
. The presence of a unilateral laminar fracture

Correct Answer & Explanation

. 15% loss of anterior vertebral body height

Explanation

Disruption of the posterior ligamentous complex (PLC) indicates a grossly unstable fracture pattern resulting in a TLICS score of 4 or higher. While severe canal compromise or severe kyphosis are factors, definitive PLC disruption is a clear indication for surgery.

Question 591

Topic: Thoracolumbar Spine & Deformity

A 14-year-old competitive gymnast presents with chronic low back pain. Radiographs demonstrate a grade II L5-S1 spondylolisthesis. Which of the following pathoanatomical features is characteristic of this condition (isthmic spondylolisthesis) as opposed to degenerative spondylolisthesis?

. An intact pars interarticularis with marked facet arthropathy
. The condition most commonly occurring at the L4-L5 level
. A defect, fracture, or elongation of the pars interarticularis
. Sagittally oriented facet joints permitting forward translation
. Frequent, rapid progression to Grade IV in adulthood

Correct Answer & Explanation

. An intact pars interarticularis with marked facet arthropathy

Explanation

Isthmic spondylolisthesis is characterized by a structural defect or elongation (stress fracture) of the pars interarticularis, most commonly at L5-S1. Degenerative spondylolisthesis features an intact pars and most frequently occurs at L4-L5.

Question 592

Topic: Thoracolumbar Spine & Deformity

A 35-year-old man falls from a height and sustains an L1 burst fracture. He is neurologically intact. Upright radiographs demonstrate 20 degrees of kyphosis and 40% loss of anterior vertebral body height. CT shows 30% canal compromise. The posterior ligamentous complex is intact on MRI. What is the most appropriate management?

. Thoracolumbosacral orthosis (TLSO) brace mobilization
. Short-segment posterior instrumentation without fusion
. Long-segment posterior instrumentation and fusion
. Anterior corpectomy and fusion
. Posterior laminectomy alone

Correct Answer & Explanation

. Thoracolumbosacral orthosis (TLSO) brace mobilization

Explanation

In neurologically intact patients with thoracolumbar burst fractures and an intact posterior ligamentous complex, non-operative management with a TLSO brace or cast provides equivalent long-term clinical outcomes compared to surgery.

Question 593

Topic: Thoracolumbar Spine & Deformity

A 68-year-old woman presents with severe low back pain and an inability to stand upright. Standing full-length radiographs reveal a sagittal vertical axis (SVA) of +12 cm, a pelvic incidence (PI) of 60 degrees, and a lumbar lordosis (LL) of 20 degrees. What are the primary radiographic targets for surgical correction of her sagittal balance?

. Decrease SVA to < 5 cm and achieve PI-LL mismatch < 10 degrees
. Increase SVA to > 5 cm and achieve PI-LL mismatch > 20 degrees
. Achieve PI-LL mismatch < 20 degrees with no change in SVA
. Decrease PI by 10 degrees
. Increase pelvic tilt to > 30 degrees

Correct Answer & Explanation

. Decrease SVA to < 5 cm and achieve PI-LL mismatch < 10 degrees

Explanation

Proper sagittal balance correction in adult spinal deformity targets a Sagittal Vertical Axis (SVA) of less than 5 cm, a Pelvic Incidence to Lumbar Lordosis (PI-LL) mismatch of less than 10 degrees, and a Pelvic Tilt (PT) of less than 20 degrees.

Question 594

Topic: Thoracolumbar Spine & Deformity

A 12-year-old boy wearing a lap belt is involved in a high-speed motor vehicle collision. Radiographs reveal a flexion-distraction injury (Chance fracture) at L2. Which of the following associated injuries must be most highly suspected and urgently evaluated?

. Aortic dissection
. Intra-abdominal hollow viscus injury
. Renal artery thrombosis
. Diaphragmatic rupture
. Pelvic ring disruption

Correct Answer & Explanation

. Aortic dissection

Explanation

Chance fractures (flexion-distraction injuries) are frequently associated with seatbelt injuries. There is a high incidence (up to 40-50%) of concurrent intra-abdominal hollow viscus injuries, making urgent general surgery evaluation critical.

Question 595

Topic: Thoracolumbar Spine & Deformity

A 14-year-old gymnast presents with persistent low back pain. Radiographs demonstrate a Grade II isthmic spondylolisthesis at L5-S1. Conservative treatment fails. What is the most common nerve root affected in this condition that causes radicular symptoms?

. L3
. L4
. L5
. S1
. S2

Correct Answer & Explanation

. L3

Explanation

In isthmic spondylolisthesis at L5-S1, the fibrocartilaginous tissue at the pars interarticularis defect (Gill nodule) hypertrophies. This mass commonly compresses the exiting L5 nerve root within the neuroforamen.

Question 596

Topic: Thoracolumbar Spine & Deformity

A 35-year-old man falls from a roof. CT scan shows a T12 burst fracture with 40% loss of vertebral body height and splaying of the pedicles. MRI shows an intact posterior ligamentous complex (PLC). Neurological exam is completely normal. What is his Thoracolumbar Injury Classification and Severity (TLICS) score and recommended treatment?

. Score 2, Non-operative management
. Score 4, Operative management
. Score 5, Operative management
. Score 2, Operative management
. Score 4, Non-operative management

Correct Answer & Explanation

. Score 2, Non-operative management

Explanation

The TLICS score is calculated as: Burst fracture morphology (2 points), intact PLC (0 points), and intact neurologic status (0 points), totaling 2 points. A score of 3 or less is typically treated non-operatively with bracing and early mobilization.

Question 597

Topic: Thoracolumbar Spine & Deformity

A 22-year-old female sustains a seatbelt injury in a high-speed motor vehicle collision. Radiographs and CT show a fracture line extending horizontally through the spinous process, pedicles, and vertebral body of L2. What associated injury must be actively ruled out?

. Aortic transection
. Renal artery thrombosis
. Intra-abdominal hollow viscus injury
. Diaphragmatic rupture
. Pelvic ring disruption

Correct Answer & Explanation

. Aortic transection

Explanation

Chance fractures (flexion-distraction injuries) sustained via seatbelts are highly associated with intra-abdominal hollow viscus injuries, occurring in up to 40-50% of cases. Prompt general surgery consultation and abdominal imaging are essential.

Question 598

Topic: Thoracolumbar Spine & Deformity

A 40-year-old construction worker with Grade II isthmic spondylolisthesis at L5-S1 complains of severe radicular pain. If surgical decompression is planned, which nerve root is most commonly compressed in this specific pathology?

. L4 nerve root
. L5 nerve root
. S1 nerve root
. S2 nerve root
. S3 nerve root

Correct Answer & Explanation

. L4 nerve root

Explanation

In isthmic spondylolisthesis at L5-S1, the L5 nerve root is most commonly compressed as it exits the neural foramen. It is typically impinged by the hypertrophic fibrocartilaginous tissue at the pars defect.

Question 599

Topic: Thoracolumbar Spine & Deformity

A 45-year-old male treated conservatively for a T12 burst fracture one year ago presents with worsening back pain and progressive kyphosis (now 35 degrees). What is the primary biomechanical rationale for performing an anterior and posterior fusion rather than a posterior-only fusion in this setting?

. To avoid injury to the conus medullaris
. To provide a vascularized bone graft
. To address the rigid anterior column deficiency and provide load-sharing
. To allow for dynamic stabilization
. To minimize blood loss

Correct Answer & Explanation

. To avoid injury to the conus medullaris

Explanation

In delayed post-traumatic kyphosis, the anterior column is often deficient and rigidly deformed. An anterior release and strut grafting provides necessary load-sharing and addresses the anterior column defect, which a posterior-only construct would likely fail to maintain.

Question 600

Topic: Thoracolumbar Spine & Deformity

A 35-year-old male falls from a height and sustains an L1 burst fracture. His neurologic examination is normal. An MRI confirms that the posterior ligamentous complex (PLC) is completely intact. What is his Thoracolumbar Injury Classification and Severity (TLICS) score, and what is the generally recommended treatment?

. Score 2, nonoperative management
. Score 4, surgical management
. Score 5, surgical management
. Score 2, surgical management
. Score 3, nonoperative management

Correct Answer & Explanation

. Score 2, nonoperative management

Explanation

The TLICS score is calculated as follows: Burst morphology (2 points), intact PLC (0 points), and normal neurologic status (0 points), giving a total score of 2. A score of 3 or less is typically treated nonoperatively.

Test Yourself

Switch to an interactive, timed exam simulation to truly master this topic.

On this Page