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6. Spine MCQs

Practice Set 285 of 379

This practice set contains high-yield board review questions covering key concepts in 6. Spine. Each clinical scenario is designed to test your diagnostic and management skills relevant to this subspecialty.

Question 5681

Topic: Thoracolumbar Spine & Deformity

A 30-year-old male sustains a T12 burst fracture after a fall from height. He has 50% canal compromise and a neurological deficit with grade 3/5 motor strength in both lower extremities (ASIA D). There is no significant kyphosis on initial imaging. What is the most appropriate surgical approach and strategy?

. Posterior decompression (laminectomy) and short-segment pedicle screw fixation (T11-L1).
. Anterior corpectomy, decompression, and reconstruction with strut graft.
. Posterior reduction, decompression via transpedicular or costotransversectomy approach, and long-segment pedicle screw fixation (T10-L2).
. Non-operative management with brace and close neurological monitoring.
. Immediate anterior and posterior combined approach for complete decompression and stabilization.

Correct Answer & Explanation

. Posterior reduction, decompression via transpedicular or costotransversectomy approach, and long-segment pedicle screw fixation (T10-L2).

Explanation

The patient has a T12 burst fracture with significant canal compromise and a neurological deficit (ASIA D). Non-operative management (D) is inappropriate. Posterior laminectomy alone (A) is generally contraindicated for burst fractures, especially with neurological deficits, as it can worsen kyphosis and instability without effectively decompressing anteriorly displaced fragments. Anterior corpectomy and reconstruction (B) effectively decompresses the cord and reconstructs the anterior column, but it may not be sufficient for severe posterior element injuries or provide enough stability alone. Immediate anterior and posterior combined approach (E) is very aggressive and reserved for highly unstable or complex deformities. The most appropriate strategy, which allows for robust decompression and stabilization from a single approach, isposterior reduction, decompression via a transpedicular or costotransversectomy approach, and long-segment pedicle screw fixation (T10-L2)(C). This approach allows for indirect and often direct decompression of the spinal canal, provides excellent stabilization, corrects kyphosis, and minimizes morbidity compared to combined approaches. Long-segment fixation (typically two levels above and two below) is generally preferred for burst fractures with neurological deficit to ensure adequate stability and load sharing.

Question 5682

Topic: 6. Spine

A 65-year-old female with long-standing, severe rheumatoid arthritis (RA) presents with progressive spastic quadriparesis, hyperreflexia, and gait disturbance. MRI of the cervical spine reveals significant atlantoaxial instability (AAI) with a posterior atlanto-dental interval (PADI) of 10 mm and C1-C2 subluxation causing spinal cord compression. She has diffuse osteopenia and multiple comorbidities related to her RA. What is the most appropriate surgical management strategy?

. Anterior cervical decompression and fusion (ACDF) at C1-C2.
. Posterior decompression (laminectomy of C1) and occipitocervical fusion.
. Posterior atlantoaxial fusion (C1-C2) using C1 lateral mass and C2 pedicle screws.
. Non-operative management with a cervical collar and close neurological monitoring.
. Transoral odontoidectomy alone.

Correct Answer & Explanation

. Posterior atlantoaxial fusion (C1-C2) using C1 lateral mass and C2 pedicle screws.

Explanation

The patient has symptomatic atlantoaxial instability (AAI) with spinal cord compression (spastic quadriparesis, hyperreflexia, gait disturbance) in the setting of severe rheumatoid arthritis. Non-operative management (D) is contraindicated due to progressive neurological deficits. Anterior cervical decompression and fusion (A) is generally not indicated for C1-C2 instability. Posterior decompression (laminectomy of C1) and occipitocervical fusion (B) is a robust option, especially for irreducible AAI or basilar invagination, but it sacrifices C0-C1 motion. Transoral odontoidectomy alone (E) provides decompression but no stability and typically requires a posterior fusion. The most appropriate and often preferred surgical management for symptomatic reducible atlantoaxial instability in RA isposterior atlantoaxial fusion (C1-C2) using C1 lateral mass and C2 pedicle screws (C). This technique provides rigid fixation and stability at the C1-C2 segment, preserves motion at C0-C1 (occiput-C1), and effectively decompresses the spinal cord by reducing the subluxation. Although osteopenia in RA can make screw fixation challenging, modern techniques usually allow for successful instrumentation. If subluxation is irreducible or there's severe bone loss/basilar invagination, occipitocervical fusion might be considered, but C1-C2 fusion is preferred for isolated, reducible AAI.

Question 5683

Topic: Thoracolumbar Spine & Deformity
A 35-year-old male sustains a T12 burst fracture after a fall, resulting in an incomplete neurological deficit (ASIA D). Imaging shows significant canal compromise (>50%) and 30 degrees of kyphosis. The TLICS score is calculated as 8. What is the most appropriate surgical management for this patient?
. Observation and bracing.
. Posterior spinal fusion and instrumentation from T10 to L2.
. Anterior decompression and fusion at T12.
. Vertebroplasty at T12.
. Short-segment posterior instrumentation without decompression.

Correct Answer & Explanation

. Posterior spinal fusion and instrumentation from T10 to L2.

Explanation

The patient has an unstable thoracolumbar burst fracture (morphology 3 points) with neurological involvement (incomplete, 3 points) and disruption of the posterior ligamentous complex (PLC is likely disrupted with 30 degrees kyphosis, 2 points). This gives a TLICS score of 3+3+2 = 8. A TLICS score of >=5 indicates a strong recommendation for surgical management. Given the significant canal compromise, kyphosis, and incomplete neurological deficit, posterior decompression (indirect via ligamentotaxis or direct via laminectomy) and fusion with long-segment instrumentation (T10-L2) is the most appropriate approach to restore stability, indirectly decompress the canal, and prevent further neurological deterioration. Anterior decompression is an option but often combined with posterior fusion or used for specific anterior column reconstruction, and less common as a standalone initial approach for burst fractures with posterior instability. Vertebroplasty is for pain relief in stable compression fractures, not unstable burst fractures with neurological deficit. Short-segment posterior instrumentation without decompression may not be sufficient for significant canal compromise and neurological deficit.

Question 5684

Topic: 6. Spine

A 10-year-old child presents with progressive kyphosis of the thoracic spine, diagnosed as Scheuermann's disease, with a Cobb angle of 80 degrees. The patient has persistent back pain unresponsive to bracing and physical therapy. What is the recommended treatment?

. Continued bracing and observation.
. Vertebroplasty of the affected vertebrae.
. Surgical correction with posterior spinal fusion and instrumentation.
. Anterior osteotomy alone.
. Physical therapy focusing on extension exercises.

Correct Answer & Explanation

. Surgical correction with posterior spinal fusion and instrumentation.

Explanation

Scheuermann's kyphosis with a Cobb angle exceeding 70-75 degrees (some say >70, others >75-80), particularly with persistent pain refractory to conservative management (bracing, PT), is an indication for surgical correction. Surgical treatment typically involves posterior spinal fusion and instrumentation to correct the deformity and stabilize the spine. Bracing is generally effective for curves between 45-75 degrees in growing children, but not for severe, progressive, or symptomatic curves >80 degrees. Vertebroplasty is for vertebral compression fractures, not structural kyphosis. Anterior osteotomy alone is insufficient and destabilizing. Physical therapy alone is not adequate for severe structural kyphosis.

Question 5685

Topic: 6. Spine

A 65-year-old male with long-standing rheumatoid arthritis presents with progressive weakness in his upper and lower extremities, hyperreflexia, and gait disturbance. Neurological examination reveals spasticity and a positive Babinski sign. What is the most likely diagnosis and crucial diagnostic investigation?

. Peripheral neuropathy; nerve conduction studies.
. Cervical myelopathy due to atlantoaxial subluxation; MRI of the cervical spine.
. Carpal tunnel syndrome; EMG.
. Rheumatoid vasculitis; biopsy of affected tissue.
. Anterior cord syndrome; spinal angiography.

Correct Answer & Explanation

. Cervical myelopathy due to atlantoaxial subluxation; MRI of the cervical spine.

Explanation

The neurological symptoms of progressive weakness, hyperreflexia, spasticity, and gait disturbance, especially in a patient with rheumatoid arthritis, are highly suggestive of cervical myelopathy. Atlantoaxial subluxation is a common and severe complication of rheumatoid arthritis, leading to spinal cord compression. MRI of the cervical spine is the crucial diagnostic investigation to visualize the spinal cord, degree of compression, and the extent of instability at the craniocervical junction. Peripheral neuropathy, carpal tunnel syndrome, and rheumatoid vasculitis would not typically present with myelopathic signs like spasticity and hyperreflexia. Anterior cord syndrome is a specific vascular event, and less likely the primary diagnosis in this chronic presentation.

Question 5686

Topic: Thoracolumbar Spine & Deformity

A 68-year-old female presents with severe debilitating low back pain, radiating into both legs, worse with standing. She has a progressive adult degenerative scoliosis with a coronal Cobb angle of 35 degrees and a sagittal vertical axis (SVA) of +8 cm. She has failed extensive conservative management. Surgical planning for this patient should primarily address:

. Isolated decompression of neural elements
. Short-segment fusion and instrumentation
. Restoration of sagittal balance with long-segment fusion
. Anterior column support without posterior fusion
. Posterior column osteotomy alone

Correct Answer & Explanation

. Restoration of sagittal balance with long-segment fusion

Explanation

In adult degenerative scoliosis, especially with a significant positive sagittal vertical axis (SVA > 5 cm), sagittal imbalance is a major contributor to pain and disability. The primary goal of surgical intervention is to restore sagittal balance and decompress neural elements. This typically requires long-segment fusion to achieve stable correction and often involves osteotomies to restore lumbar lordosis. Isolated decompression addresses symptoms but not the underlying instability or deformity. Short-segment fusion may lead to junctional kyphosis or continued imbalance. Anterior column support alone is insufficient without posterior fixation. Posterior column osteotomy alone may not provide adequate correction for substantial sagittal imbalance.

Question 5687

Topic: 6. Spine

A 70-year-old male with severe neurogenic claudication due to lumbar spinal stenosis (L4-5) has failed 6 months of conservative management including NSAIDs, physical therapy, and epidural steroid injections. His symptoms significantly limit his ability to walk more than 50 meters. He has no progressive neurological deficits. What is the primary indication for surgical intervention in this patient?

. Presence of spondylolisthesis
. Presence of scoliosis
. Persistent debilitating symptoms despite adequate conservative therapy
. Motor weakness >3/5
. Bladder and bowel dysfunction

Correct Answer & Explanation

. Persistent debilitating symptoms despite adequate conservative therapy

Explanation

For lumbar spinal stenosis, in the absence of acute neurological emergencies like progressive motor weakness (e.g., foot drop) or cauda equina syndrome (bladder/bowel dysfunction), the primary indication for elective surgical decompression is persistent, debilitating symptoms (such as neurogenic claudication or severe radicular pain) that have failed an adequate trial of conservative management. While spondylolisthesis or scoliosis might be present and influence the specific surgical technique (e.g., requiring fusion), they are not the sole primary indication for surgery in the absence of debilitating symptoms or neurological deficits.

Question 5688

Topic: 6. Spine

A 15-year-old female with progressive adolescent idiopathic scoliosis (AIS) has a 70-degree main thoracic curve (T5-T12) with significant truncal decompensation and a kyphotic component. Pulmonary function tests show FVC 65% of predicted. Previous bracing failed. What is the most appropriate surgical strategy for correction?

. Anterior spinal fusion with instrumentation.
. Posterior spinal fusion with pedicle screw instrumentation.
. Vertebral body tethering (VBT).
. Anterior and posterior combined fusion.
. Observation with serial radiographs and pulmonary function tests.

Correct Answer & Explanation

. Posterior spinal fusion with pedicle screw instrumentation.

Explanation

For a 15-year-old female with a 70-degree main thoracic curve and significant truncal decompensation due to AIS, posterior spinal fusion with pedicle screw instrumentation is the gold standard surgical treatment. This approach allows for excellent 3D correction of the deformity (coronal, sagittal, and axial plane), significant correction of the kyphosis, and stable fixation. Anterior fusion alone is less effective for large thoracic curves and often carries higher risks in the thoracic spine. VBT is typically considered for skeletally immature patients with smaller curves and aims to modulate growth, which is less effective for a 15-year-old with a 70-degree curve. Combined anterior and posterior approaches are reserved for very rigid or severe curves (often >90 degrees) or specific congenital deformities. Observation is not appropriate given the curve magnitude and pulmonary compromise.

Question 5689

Topic: Thoracolumbar Spine & Deformity

A 72-year-old female presents with severe, chronic low back pain radiating into both legs, worse with standing and ambulation, and significantly improved with sitting. Radiographs show a long-segment degenerative lumbar scoliosis (40 degrees) with a positive sagittal vertical axis (SVA) of 8 cm. Conservative management has failed. What is the primary goal of surgical correction for this patient?

. Decompression of neural elements only.
. Correction of coronal plane deformity (scoliosis) only.
. Restoration of sagittal balance and achieving a neutral or slightly negative SVA.
. Placement of a short-segment fusion to stabilize the most painful levels.
. Prevention of further curve progression.

Correct Answer & Explanation

. Restoration of sagittal balance and achieving a neutral or slightly negative SVA.

Explanation

This patient presents with adult degenerative scoliosis with severe symptoms and a positive sagittal vertical axis (SVA) of 8 cm, indicating significant sagittal imbalance. While decompression and coronal correction are components, the primary goal of surgical correction in adult spinal deformity, especially with a positive SVA, is the restoration of sagittal balance. Sagittal imbalance is strongly correlated with pain and functional disability. Correcting the positive SVA (ideally to a slightly negative or neutral range, -2 to +2 cm) by restoring lumbar lordosis and harmonizing pelvic parameters is crucial for long-term functional improvement and pain relief. Simply decompressing or correcting the coronal curve without addressing sagittal balance often leads to suboptimal outcomes or 'flatback syndrome.'

Question 5690

Topic: 6. Spine

A 55-year-old male with poorly controlled diabetes presents with severe, unrelenting low back pain, fever, chills, and elevated inflammatory markers (ESR 100 mm/hr, CRP 150 mg/L). MRI shows L5-S1 discitis and osteomyelitis with a small epidural abscess, but neurological examination is entirely intact. What is the primary goal of initial management?

. Immediate surgical decompression and debridement.
. Initiation of empirical broad-spectrum intravenous antibiotics.
. Placement of a percutaneous drain for the epidural abscess.
. Aggressive pain management with narcotics and muscle relaxants.
. Referral for immediate radiation therapy.

Correct Answer & Explanation

. Initiation of empirical broad-spectrum intravenous antibiotics.

Explanation

This patient presents with spinal infection (discitis/osteomyelitis) and an epidural abscess. While antibiotics are crucial, the most urgent initial step for any epidural abscess, even without overt neurological deficit, is to identify the pathogen and source. For a small epidural abscess with an intact neurological exam, the primary goal of initial management is obtaining a tissue diagnosis (via CT-guided percutaneous biopsy) and then initiating appropriate broad-spectrum intravenous antibiotics. Surgical decompression is indicated urgently if there is progressive neurological deficit, severe spinal instability, or failure of conservative (antibiotic) management. Without neurological compromise, immediate surgery is generally not the first step. Pain management and radiation therapy alone do not address the infection. The answer states 'primary goal of initial management' and while antibiotics are part, getting the diagnosis (culture) to guide treatment is critical before initiating empirical antibiotics without knowing the pathogen.

Question 5691

Topic: 6. Spine

A 55-year-old male with poorly controlled diabetes presents with severe, unrelenting low back pain, fever, chills, and elevated inflammatory markers (ESR 100 mm/hr, CRP 150 mg/L). MRI shows L5-S1 discitis and osteomyelitis with a small epidural abscess, but neurological examination is entirely intact. What is the primary goal of initial management?

. Immediate surgical decompression and debridement.
. Initiation of empirical broad-spectrum intravenous antibiotics after obtaining cultures.
. Placement of a percutaneous drain for the epidural abscess.
. Aggressive pain management with narcotics and muscle relaxants.
. Referral for immediate radiation therapy.

Correct Answer & Explanation

. Initiation of empirical broad-spectrum intravenous antibiotics after obtaining cultures.

Explanation

This patient presents with spinal infection (discitis/osteomyelitis) and a small epidural abscess. While surgical decompression is indicated for progressive neurological deficit or severe instability, for a patient with an intact neurological exam, the primary goal of initial management is to identify the causative organism and initiate appropriate antibiotics. This typically involves obtaining cultures (e.g., via CT-guided biopsy of the disc space or epidural abscess) followed by the immediate initiation of empirical broad-spectrum intravenous antibiotics. This combination aims to control the infection and prevent neurological deterioration. Percutaneous drainage may be considered for larger abscesses but isn't always primary. Pain management is supportive. Radiation therapy is not indicated for infection.

Question 5692

Topic: 6. Spine

A 68-year-old female presents with progressive sagittal imbalance, chronic debilitating low back pain, and claudication-type symptoms that limit her walking distance to less than 100 meters. Radiographs reveal severe adult degenerative scoliosis with a Pelvic Incidence (PI) of 60 degrees and a Lumbar Lordosis (LL) of 20 degrees. Her Sagittal Vertical Axis (SVA) is +15 cm. For surgical planning, which of the following radiographic parameters is the primary target for correction to improve her clinical symptoms?

. Pelvic Tilt (PT) less than 20 degrees.
. Sacral Slope (SS) greater than 30 degrees.
. Thoracic Kyphosis (TK) between 20-50 degrees.
. PI-LL mismatch less than 10 degrees.
. C7 plumb line falling within 2 cm of the sacral promontory.

Correct Answer & Explanation

. PI-LL mismatch less than 10 degrees.

Explanation

The patient exhibits severe sagittal imbalance (SVA +15 cm) and a significant PI-LL mismatch (60-20 = 40 degrees). In adult spinal deformity, the PI-LL mismatch is a crucial parameter that directly correlates with clinical outcomes and quality of life. The goal of surgical correction for sagittal balance is typically to achieve a PI-LL mismatch of less than 10 degrees (ideally within 0 to +10 degrees) and an SVA of less than 5 cm. While other parameters like PT and TK are important components of global spinal alignment, the PI-LL mismatch is considered a primary driver of sagittal balance and symptoms in degenerative scoliosis.

Question 5693

Topic: 6. Spine

A 70-year-old patient with long-standing rheumatoid arthritis (RA) and poorly controlled disease presents with progressive upper extremity weakness, hyperreflexia, and gait ataxia. Plain radiographs of the cervical spine show an atlantoaxial distance (ADI) of 7 mm on flexion and a Basilar Invagination with migration of the odontoid process above McGregor's line. What is the most appropriate surgical management for this patient?

. Anterior cervical discectomy and fusion (ACDF).
. Posterior atlantoaxial fusion.
. Occipitocervical fusion.
. Laminectomy of C1 and C2.
. Halo vest immobilization.

Correct Answer & Explanation

. Occipitocervical fusion.

Explanation

The patient exhibits symptoms and radiographic signs of significant cervical myelopathy due to atlantoaxial instability (ADI > 3.5 mm is unstable) and basilar invagination, common complications of advanced RA affecting the cervical spine. Basilar invagination indicates cranial settling with compression of the brainstem/spinal cord. While posterior atlantoaxial fusion addresses atlantoaxial instability, the presence of basilar invagination (odontoid migration above McGregor's line) and myelopathy often necessitates extending the fusion to include the occiput, i.e., occipitocervical fusion, especially when there is evidence of brainstem compression or if the C1-C2 facets are significantly eroded making C1-C2 fixation impossible. Therefore, occipitocervical fusion is the most appropriate and definitive management for this combined instability and compression. ACDF is for lower cervical pathology. Laminectomy would worsen instability. Halo vest is temporary stabilization.

Question 5694

Topic: 6. Spine

A 30-year-old male sustains an L1 burst fracture (AO/OTA type A3) after falling from a ladder. Neurological examination is completely normal. CT scan shows 60% canal compromise and a local kyphosis of 15 degrees. Considering the absence of neurological deficit and the specific fracture morphology, which factor is most crucial in deciding between non-operative management with bracing versus surgical fixation?

. The patient's age and activity level.
. The percentage of canal compromise alone.
. The presence of significant posterior ligamentous complex (PLC) injury.
. The associated fracture of the transverse processes.
. The amount of vertebral body comminution.

Correct Answer & Explanation

. The presence of significant posterior ligamentous complex (PLC) injury.

Explanation

For thoracolumbar burst fractures without neurological deficit, the integrity of the posterior ligamentous complex (PLC) is the most crucial factor in determining spinal stability and the risk of progressive kyphosis. If the PLC is intact, non-operative management with bracing can be considered, even with significant canal compromise, as the spine maintains stability. However, a disrupted PLC (often indicated by spinous process widening, facet distraction, or specific MRI findings) indicates instability and generally necessitates surgical stabilization to prevent progressive deformity and potential neurological sequelae. Canal compromise alone, if the PLC is intact, does not mandate surgery in an neurologically intact patient. Patient age and activity level are secondary considerations.

Question 5695

Topic: Thoracolumbar Spine & Deformity

A 14-year-old female gymnast presents with chronic lower back pain. Lateral lumbar radiographs demonstrate a Grade II isthmic spondylolisthesis at L5-S1. The pelvic incidence (PI) is measured at 75 degrees. Which of the following statements regarding her spinopelvic parameters is most accurate?

. Pelvic incidence is a dynamic parameter that decreases with forward flexion
. High pelvic incidence increases shear forces at the lumbosacral junction, predisposing to slip progression
. Pelvic incidence is calculated as the difference between pelvic tilt and sacral slope
. A high pelvic incidence necessitates a compensatory decrease in lumbar lordosis to maintain sagittal balance
. Surgical reduction of the spondylolisthesis will significantly decrease the pelvic incidence

Correct Answer & Explanation

. High pelvic incidence increases shear forces at the lumbosacral junction, predisposing to slip progression

Explanation

Pelvic incidence (PI) is a fixed morphologic parameter (PI = Pelvic Tilt + Sacral Slope) that does not change with posture. A high PI (>60 degrees) correlates with a high sacral slope, which increases the shear forces across the pars interarticularis at the L5-S1 junction. This strongly predisposes patients to the development and progression of isthmic spondylolisthesis. A high PI requires a compensatoryincreasein lumbar lordosis.

Question 5696

Topic: 6. Spine
A 45-year-old male presents with chronic axial low back pain without radiculopathy, suspected to be discogenic. Which of the following nerve structures primarily innervates the outer annulus fibrosus and posterior longitudinal ligament, potentially mediating this type of pain?
. Sinuvertebral nerve (recurrent meningeal nerve of Luschka)
. Gray ramus communicans
. Ventral ramus
. Dorsal ramus
. Spinal nerve root

Correct Answer & Explanation

. Sinuvertebral nerve (recurrent meningeal nerve of Luschka)

Explanation

The sinuvertebral nerve (or recurrent meningeal nerve of Luschka) primarily innervates the outer one-third of the annulus fibrosus, the posterior longitudinal ligament, and the periosteum of the posterior vertebral body. It is responsible for nociceptive transmission from these structures, contributing to discogenic low back pain. The gray ramus communicans innervates blood vessels and glands. The ventral and dorsal rami are branches of the spinal nerve that innervate muscles and skin. The spinal nerve root itself transmits sensory and motor information from specific segments but does not directly innervate the posterior annulus in this manner.

Question 5697

Topic: 6. Spine

A patient's MRI report describes a "focal displacement of disc material beyond the limits of the intervertebral disc space, with the base of the displaced material broader than any dimension of the displaced material itself." This description is most consistent with which type of disc herniation?

. Disc extrusion
. Disc protrusion
. Disc sequestration
. Annular tear
. Disc bulge

Correct Answer & Explanation

. Disc protrusion

Explanation

This description accurately defines a disc protrusion. In a protrusion, the disc material extends beyond the posterior vertebral margin, but the widest dimension of the herniated material, in any plane, is narrower than the base (neck) of the herniation. An extrusion means the widest dimension of the herniated material is greater than the base, or it has lost continuity with the parent disc. Sequestration is a free fragment. An annular tear is damage to the annulus, and a disc bulge involves circumferential extension of disc material beyond the margins of the vertebral body, typically involving more than 50% of the circumference.

Question 5698

Topic: 6. Spine

A 38-year-old male presents to the emergency department with acute onset severe bilateral leg pain, saddle anesthesia, recent urinary retention, and diminished rectal tone. What is the MOST immediate and critical management step?

. Initiate high-dose oral corticosteroids
. Order an urgent MRI of the lumbar spine
. Schedule an epidural steroid injection
. Refer for physical therapy
. Administer strong opioid analgesics

Correct Answer & Explanation

. Order an urgent MRI of the lumbar spine

Explanation

The patient's symptoms (bilateral leg pain, saddle anesthesia, urinary retention, diminished rectal tone) are classic for Cauda Equina Syndrome (CES), which is a surgical emergency. The most immediate and critical step is to confirm the diagnosis with an urgent MRI of the lumbar spine, followed by emergent surgical decompression to prevent permanent neurological deficits. While pain management is important, confirming and treating the underlying pathology takes precedence. Oral corticosteroids and epidural injections are not indicated for CES.

Question 5699

Topic: 6. Spine

A posterolateral disc herniation at the L4-L5 level typically compresses which nerve root?

. L3 nerve root
. L4 nerve root
. L5 nerve root
. S1 nerve root
. S2 nerve root

Correct Answer & Explanation

. L5 nerve root

Explanation

A posterolateral disc herniation usually affects the nerve root exitingbelowthat level. Therefore, an L4-L5 disc herniation typically compresses the L5 nerve root. The L4 nerve root exits at the L4-L5 foramen, superior to the disc space, and is generally spared in a standard posterolateral herniation at this level.

Question 5700

Topic: 6. Spine

A patient with suspected L5 radiculopathy due to a lumbar disc herniation would MOST likely exhibit weakness in which muscle group?

. Knee extensors (quadriceps)
. Ankle dorsiflexors (tibialis anterior)
. Plantarflexors (gastrocnemius/soleus)
. Hip flexors (iliopsoas)
. Knee flexors (hamstrings)

Correct Answer & Explanation

. Ankle dorsiflexors (tibialis anterior)

Explanation

L5 radiculopathy is classically associated with weakness of ankle dorsiflexion (tibialis anterior), toe extension (extensor hallucis longus), and sometimes hip abduction (gluteus medius/minimus). Quadriceps (knee extensors) are primarily L3-L4. Plantarflexors are S1-S2. Hip flexors are L1-L3. Hamstrings (knee flexors) are L5-S2.

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