You are interested in learning a new technique for minimally invasive total knee arthroplasty. The Keyhole Genuflex system seems appealing to you because the instrumentation comes with wireless controls. What is an acceptable arrangement to learn mor

Keyhole will pay your expenses to attend a workshop at their company headquarters, to learn how to implant the Genuflex knee and to see how the implant is manufactured and tested.

A 21-year-old collegiate female cross-country athlete reports right hip pain that begins about 12 miles into a run, followed by pain resolution when she discontinues running. However, each time she tries to resume a running program, she experiences r

cessation of running and implementation of cross training until healing is complete.

Surgical treatment for symptomatic disk herniations is associated with which of the following?

Early relief of pain sustained out to 2 years

A 27-year-old man now reports dorsiflexion and inversion weakness after an automobile collision 6 months ago in which compartment syndrome developed isolated to the anterior and deep posterior compartments. Examination reveals the development of a pr

Anterior tibialis tendon transfer to the dorsolateral midfoot

A 12-year-old boy with hemophilia A and no known inhibitors sustains a tibia fracture and has pain with passive motion of the deep toe flexors. Appropriate management should consist of

factor VIII replacement, followed by assessment of compartment pressures.

Dr. Hutaif Spine Surgery Review: Orthopedic Spine Care

Question 1

A 65-year-old male undergoes a multi-level posterior cervical laminectomy and fusion from C3 to C6 for cervical spondylotic myelopathy. On postoperative day 1, he is noted to have a new-onset right deltoid and biceps weakness (grade 2/5). His sensation is intact, and his myelopathic symptoms in the lower extremities have improved. What is the most appropriate next step in management?

Explanation

The patient is presenting with a C5 palsy, a well-known complication after cervical decompression (especially laminectomy and fusion). It typically presents with deltoid and/or biceps weakness with or without sensory changes, often occurring 1-3 days postoperatively. Since the patient's long-tract signs are improving and the deficit is isolated to C5, the standard of care is observation and physical therapy. The majority of patients recover spontaneously within 6 months.

Question 2

A 35-year-old male falls from a roof and sustains a T12 burst fracture. He is neurologically intact. MRI demonstrates definitive disruption of the posterior ligamentous complex (PLC). According to the Thoracolumbar Injury Classification and Severity (TLICS) score, what is his score and the recommended management?

Explanation

The TLICS score is calculated based on three categories: injury morphology, integrity of the PLC, and neurologic status. Burst fracture = 2 points. Intact neurology = 0 points. Disrupted PLC = 3 points. Total score = 5. A TLICS score >= 5 is an indication for operative management. A score of 4 can be managed operatively or non-operatively based on the surgeon's clinical judgment.

Question 3

A 24-year-old male is brought to the emergency department after a motor vehicle collision. He is awake, alert, and able to converse appropriately. Imaging reveals bilateral jumped facets at C5-C6. Neurologic examination demonstrates a C6 ASIA B spinal cord injury. What is the most appropriate initial management?

Explanation

In an awake, alert, and cooperative patient with a cervical facet dislocation, rapid closed reduction via cranial traction is indicated without the absolute prerequisite of an MRI. The awake patient can provide continuous neurologic feedback during the reduction process. If the patient were obtunded or unable to participate in a neurologic exam, an MRI would be required first to evaluate for a compressive disc herniation that could be pulled into the canal during reduction.

Question 4

A 72-year-old male with long-standing ankylosing spondylitis presents to the ED with severe neck pain following a minor ground-level fall. Lateral radiographs demonstrate a 'chalk-stick' extension fracture through the C6-C7 disc space. He is currently neurologically intact. What is the most appropriate next step in management?

Explanation

Patients with ankylosing spondylitis are highly susceptible to highly unstable shear and extension fractures, even from low-energy trauma. These fractures are notoriously associated with epidural hematomas and progressive spinal cord injury. Advanced imaging (CT to fully characterize the fracture and MRI to rule out epidural hematoma) is mandatory. Treatment is typically long-segment operative stabilization, as these highly unstable fractures heal poorly and risk catastrophic neurologic deterioration in orthoses like a halo vest.

Question 5

A 45-year-old female presents with progressive thoracic myelopathy. MRI demonstrates a large, central, calcified disc herniation at T8-T9 causing severe cord compression. Which of the following surgical approaches is generally contraindicated for this pathology?

Explanation

A standard posterior laminectomy is strongly contraindicated for central or paracentral thoracic disc herniations, especially if calcified. Attempting to manipulate the thoracic spinal cord posteriorly to access an anteriorly situated central disc leads to a highly unacceptable risk of catastrophic spinal cord injury (paraplegia). An anterior or lateral approach (such as transthoracic, VATS, or lateral extracavitary) must be utilized to safely remove the disc without retracting the cord.

Question 6

A 60-year-old male with a history of renal cell carcinoma presents with acute-onset bilateral lower extremity weakness. MRI reveals a large metastatic lesion at T10 causing high-grade epidural spinal cord compression. The NOMS framework is utilized to guide treatment. Given that renal cell carcinoma is highly radioresistant, what is the most appropriate management?

Explanation

The NOMS (Neurologic, Oncologic, Mechanical, Systemic) framework dictates that for radioresistant tumors (like renal cell carcinoma, melanoma, thyroid, and GI tumors) causing high-grade epidural spinal cord compression, standard cEBRT is ineffective. SBRT is effective against radioresistant tumors but requires a 'safe margin' of 2-3 mm from the spinal cord to prevent radiation myelitis. Therefore, 'separation surgery' (decompression to create a margin) followed by post-operative SBRT is the gold standard.

Question 7

A 3-year-old female is diagnosed with congenital scoliosis secondary to a fully segmented hemivertebra at L2. Beside a total spine MRI to evaluate for neural axis abnormalities, what routine screening test is most critical to obtain?

Explanation

Congenital scoliosis occurs due to a failure of formation or failure of segmentation during embryogenesis (weeks 4-6). It is highly associated with other congenital anomalies in the VACTERL spectrum. Up to 20-30% of these patients will have genitourinary anomalies (unilateral kidney, horseshoe kidney, etc.). Therefore, a renal ultrasound is a mandatory screening test for all patients diagnosed with congenital scoliosis, in addition to an echocardiogram and total spine MRI.

Question 8

A 14-year-old gymnast presents with severe low back pain and radiating right leg pain. Imaging reveals a Grade II isthmic spondylolisthesis at L5-S1. She has failed 6 months of non-operative management. Her leg pain is primarily in the L5 dermatome. What is the pathomechanism of her specific radiculopathy?

Explanation

In L5-S1 isthmic spondylolisthesis, the nerve root most commonly affected is the L5 nerve root (the exiting root). It gets compressed within the neural foramen by the hypertrophied fibrocartilaginous mass at the pars interarticularis defect (Gill nodule). This is in contrast to a classic L4-L5 degenerative spondylolisthesis, which most commonly compresses the traversing L5 nerve root in the lateral recess.

Question 9

A 65-year-old female with long-standing rheumatoid arthritis presents with severe suboccipital neck pain. Flexion-extension radiographs demonstrate an anterior atlantodens interval (ADI) of 8 mm and a posterior atlantodens interval (PADI) of 12 mm. She has mild signs of myelopathy. If surgical stabilization is performed, what radiographic parameter is the most important predictor of postoperative neurologic recovery?

Explanation

In rheumatoid cervical spine instability (specifically atlantoaxial subluxation), the posterior atlantodens interval (PADI), also known as the space available for the cord (SAC), is the most reliable predictor of neurologic recovery. A PADI < 14 mm is generally an absolute indication for surgery. A PADI < 10 mm indicates a very poor prognosis for significant neurologic recovery even after adequate surgical decompression and stabilization.

Question 10

A 45-year-old male presents with acute severe right arm pain. Examination reveals numbness in the right middle finger, weakness in right elbow extension, and an absent right triceps reflex. Which cervical nerve root is most likely compressed?

Explanation

The clinical presentation is classic for a C7 radiculopathy. The C7 nerve root provides sensation to the middle finger, motor function for elbow extension (triceps) and wrist flexion, and is associated with the triceps reflex. A C6 radiculopathy would affect the thumb/index finger, wrist extension, and brachioradialis reflex.

Question 11

An 8-year-old boy is evaluated for a short, webbed neck and a low posterior hairline. He has significantly restricted cervical motion. Diagnosis of Klippel-Feil syndrome is made. Due to the altered biomechanics of his cervical spine, at which location is he at the greatest risk for developing clinically significant hypermobility and subsequent neurologic injury?

Explanation

Klippel-Feil syndrome is characterized by congenital fusion of two or more cervical vertebrae. The classic clinical triad is short neck, low hairline, and limited motion. The segments adjacent to the fused vertebrae (frequently the occipitocervical junction or segments immediately caudad) are subjected to massively increased biomechanical stress, leading to hypermobility, instability, and potential spinal cord compression over time.

Question 12

A 68-year-old female presents with severe back pain and forward-leaning posture. Standing 36-inch radiographs demonstrate adult spinal deformity. Her pelvic incidence (PI) is measured at 55 degrees, pelvic tilt (PT) is 30 degrees, and lumbar lordosis (LL) is 25 degrees. What is her PI-LL mismatch, and what is the generally accepted surgical target for this parameter?

Explanation

The Pelvic Incidence minus Lumbar Lordosis (PI - LL) mismatch is a critical parameter in adult spinal deformity correction. In this patient, PI (55) - LL (25) = 30 degrees. The SRS-Schwab classification defines the ideal target for surgical correction as a PI-LL mismatch of within 10 degrees (ideally < 9 degrees) to optimize sagittal balance, reduce adjacent segment disease, and improve patient-reported outcomes.

Question 13

An 82-year-old male with severe COPD and heart failure sustains a Type II odontoid fracture after a ground-level fall. The fracture is displaced 2 mm. What is the most appropriate management, and what is the primary rationale against using a halo vest in this specific patient population?

Explanation

In the elderly (particularly >80 years old with comorbidities), Type II odontoid fractures have a high nonunion rate. However, a fibrous nonunion is often clinically well-tolerated. Operative intervention carries significant morbidity. A halo vest is heavily contraindicated in the elderly due to severe complications, including respiratory failure, difficulty swallowing, and a mortality rate that can approach 40%. A rigid cervical collar is the safest management for elderly patients who are poor surgical candidates.

Question 14

A 35-year-old male complains of severe, shooting left leg pain that wraps around the front of his knee and down the medial aspect of his lower leg. MRI reveals a massive 'far lateral' (extraforaminal) disc herniation at the L4-L5 level on the left side. Which nerve root is most likely being compressed?

Explanation

The anatomy of lumbar nerve roots dictates that a central or paracentral disc herniation compresses the traversing nerve root (e.g., L4-L5 paracentral disc compresses the L5 root). However, a 'far lateral' or extraforaminal disc herniation compresses the exiting nerve root at that level. At L4-L5, the exiting nerve root is L4. Compression of L4 results in pain over the anterior thigh and medial leg, with possible quadriceps weakness and decreased patellar reflex.

Question 15

A 55-year-old male intravenous drug user presents with 4 weeks of severe localized back pain and low-grade fevers. He is neurologically intact. MRI confirms discitis and osteomyelitis at L3-L4 without spinal cord compression. Two sets of blood cultures are drawn and are negative at 48 hours. What is the most appropriate next step in management?

Explanation

In a hemodynamically stable, neurologically intact patient with suspected pyogenic vertebral osteomyelitis/discitis, it is crucial to obtain a microbiologic diagnosis before initiating antibiotics. If blood cultures are negative, the gold standard next step is a percutaneous image-guided (CT-guided) biopsy of the affected disc space/vertebra. Empiric antibiotics should be withheld (if clinically safe) to maximize the yield of the biopsy.

Question 16

A 14-year-old female presents for evaluation of adolescent idiopathic scoliosis (AIS). She has a right thoracic curve of 55 degrees. Her neurologic exam reveals normal strength and sensation, but you note that her superficial abdominal reflexes are briskly present on the left and entirely absent on the right. What is the most appropriate next step?

Explanation

Asymmetric superficial abdominal reflexes in a patient with presumed AIS are a 'red flag' for an underlying intraspinal anomaly, such as syringomyelia, Chiari malformation, or a tethered cord. This reflex is elicited by stroking the skin of the abdomen, causing umbilicus deviation. Atypical curve patterns (left thoracic), rapid progression, pain, or asymmetric abdominal reflexes mandate an MRI of the entire neuraxis prior to any surgical intervention.

Question 17

A 16-year-old male is evaluated for a progressive 'hump back'. Standing lateral radiographs reveal a thoracic kyphosis of 65 degrees. He is diagnosed with Scheuermann's kyphosis. According to the classic Sorensen criteria, what specific radiographic finding confirms this diagnosis?

Explanation

Scheuermann's disease is a structural kyphosis of the thoracic or thoracolumbar spine occurring during adolescence. The classic Sorensen radiographic criteria require the presence of anterior wedging of at least 5 degrees in three or more consecutive vertebrae. Other associated findings include endplate irregularities, Schmorl's nodes, and narrowing of the disc spaces, but the multi-level wedging is the defining diagnostic criterion.

Question 18

A 65-year-old male with a known history of severe cervical spinal stenosis trips and falls forward, striking his chin on a coffee table. In the ED, he demonstrates profound weakness in his bilateral hands and arms (1/5 strength), but is able to move his legs relatively well against resistance (4/5 strength). He has patchy sensory loss below the neck. Which spinal cord syndrome does this represent?

Explanation

This is a classic presentation of Central Cord Syndrome, which typically occurs after a hyperextension injury in an older patient with pre-existing cervical spondylosis. The injury disproportionately affects the central grey matter and medial aspects of the corticospinal tracts. Because the cervical motor tracts (arms/hands) are located more medially than the lumbar/sacral tracts (legs) in the spinal cord, patients exhibit much greater upper extremity weakness compared to the lower extremities.

Question 19

A 22-year-old male is a restrained driver (lap belt only) in a high-speed MVC. He presents with a transverse ecchymosis across his abdomen. Radiographs and CT show a horizontal fracture line passing through the spinous process, pedicles, and vertebral body of L2. What associated injury is classically most critical to rule out in this specific fracture pattern?

Explanation

The patient has sustained a Chance fracture, which is a flexion-distraction injury often caused by a lap-belt acting as a fulcrum during rapid deceleration. This injury mechanism causes significant anterior compression and massive posterior column distraction. Chance fractures are highly associated with intra-abdominal injuries, particularly hollow viscus injuries (bowel rupture/ischemia), which occur in up to 30-50% of cases and require urgent general surgery evaluation.

Question 20

A 65-year-old female presents with severe neurogenic claudication and is found to have a grade 1 degenerative spondylolisthesis at L4-L5 with severe central stenosis. She has failed 6 months of comprehensive non-operative management. According to the results of the Spine Patient Outcomes Research Trial (SPORT) for degenerative spondylolisthesis, what is the expected outcome if she elects for surgery versus continued non-operative care?

Explanation

The SPORT trial for degenerative spondylolisthesis demonstrated that patients treated with surgical decompression and fusion had significantly greater improvement in pain, function, and satisfaction compared to those treated non-operatively. This treatment effect was maintained at 4-year and 8-year follow-ups. While non-operative patients did show modest improvements, the operative cohort experienced definitively superior outcomes.

Question 21

A 55-year-old male undergoes a 9-hour posterior instrumented spinal fusion for adult spinal deformity. He has a history of obesity, hypertension, and obstructive sleep apnea. On postoperative day 1, he complains of painless, bilateral vision loss. Pupillary reflexes are sluggish. What is the most significant intraoperative risk factor associated with this patient's postoperative visual loss (POVL)?

Explanation

The patient is experiencing Ischemic Optic Neuropathy (ION), the most common cause of Postoperative Visual Loss (POVL) after spine surgery. Key risk factors include prone positioning, prolonged operative time (>6 hours), high estimated blood loss (>1000 mL), male sex, obesity, and the use of a Wilson frame (which places the head dependent). Direct ocular pressure causes central retinal artery occlusion (CRAO), which is typically unilateral and painful with periorbital swelling, whereas ION is typically bilateral and painless.

Question 22

A 68-year-old male with a long-standing history of Ankylosing Spondylitis presents to the emergency department with severe neck pain following a ground-level fall. Initial plain radiographs of the cervical spine are obscured by the shoulders and appear 'unremarkable'. The patient is neurologically intact. What is the most appropriate next step in management?

Explanation

Patients with Ankylosing Spondylitis (AS) have a highly rigid, osteopenic spine that is extremely susceptible to fracture even from minor trauma. A 'chalk stick' fracture must be assumed in an AS patient with new back or neck pain. Plain radiographs are notoriously inadequate due to altered anatomy and overlapping structures. CT or MRI of the entire spine is mandatory. MRI is particularly useful to rule out epidural hematoma, which occurs in up to 20% of these fractures and can lead to delayed neurologic deterioration.

Question 23

A 25-year-old male falls from a 30-foot height. Imaging reveals a U-shaped sacral fracture with a transverse fracture line through the S1-S2 disc space and bilateral vertical transforaminal fractures. He has saddle anesthesia and sphincter dysfunction. What is the most appropriate surgical treatment for this fracture pattern?

Explanation

A U-type sacral fracture represents a spinopelvic dissociation where the axial skeleton is separated from the pelvic ring. Due to the high degree of instability and the translation/kyphosis of the upper sacrum, standard iliosacral screws are insufficient to resist the sheer forces. Lumbopelvic fixation (typically extending from L4/L5 to the ilium) is required to restore mechanical stability and allow mobilization. Decompression is also indicated given the neurologic deficit.

Question 24

A 34-year-old female sustains a T12 burst fracture following a motor vehicle collision. She has normal strength and sensation in bilateral lower extremities (ASIA E). MRI demonstrates definitive disruption of the posterior ligamentous complex (PLC). According to the Thoracolumbar Injury Classification and Severity Score (TLICS), what is her total score and the recommended management?

Explanation

The TLICS score is calculated based on three categories. 1. Morphology: Burst fracture = 2 points. 2. Neurologic status: Intact = 0 points. 3. Posterior Ligamentous Complex (PLC): Definitively disrupted = 3 points. Total score = 5 points. A score of ≤3 suggests non-operative treatment, 4 is indeterminate (surgeon's choice), and ≥5 indicates surgical stabilization.

Question 25

In the surgical planning for a 62-year-old female with adult spinal deformity, achieving optimal sagittal balance is critical to prevent adjacent segment disease and mechanical failure. Which of the following defines the ideal relationship between Pelvic Incidence (PI) and Lumbar Lordosis (LL)?

Explanation

Pelvic incidence (PI) is a fixed morphologic parameter of the pelvis, while lumbar lordosis (LL) is a dynamic postural parameter. The goal of adult spinal deformity surgery is to restore harmonious spinopelvic alignment. Schwab's criteria for successful realignment indicate that the mismatch between PI and LL should be ≤ 10 degrees (PI - LL ≤ 10°). Pelvic Tilt (PT) should ideally be < 20°, and the Sagittal Vertical Axis (SVA) < 5 cm.

Question 26

A 40-year-old male is brought to the trauma bay intubated and obtunded following a high-speed rollover collision. Lateral cervical spine radiographs demonstrate a bilateral C5-C6 facet dislocation. What is the most appropriate next step in management?

Explanation

In an obtunded patient with a cervical facet dislocation, clinical neuromonitoring during reduction is impossible. Therefore, an MRI must be obtained prior to any reduction maneuvers (closed or open) to rule out an anterior disc herniation. If a disc herniation is present, reduction without prior discectomy can cause the herniated disc material to be pulled back into the spinal canal, leading to acute spinal cord compression and catastrophic neurologic injury. If the patient were awake and cooperative, an immediate closed reduction under traction could be attempted before MRI.

Question 27

An 82-year-old female sustains a Type II odontoid fracture after a fall down the stairs. The fracture demonstrates 6 mm of posterior displacement. She is neurologically intact. Which of the following factors is most strongly associated with an increased risk of nonunion if managed non-operatively?

Explanation

Risk factors for nonunion in Type II odontoid fractures include age > 50 years, initial displacement > 5 mm, angulation > 10 degrees, and a delay in treatment. Posterior displacement is a risk factor for nonunion compared to anterior displacement, but displacement magnitude (> 5 mm) is the most classically tested and highly predictive variable. Operative fixation is generally favored in patients who can tolerate surgery if these risk factors are present.

Question 28

A 55-year-old breast cancer patient presents with severe mechanical back pain. MRI shows a metastatic lesion at T11. The Spinal Instability Neoplastic Score (SINS) is being calculated to determine if surgical stabilization is indicated. Which of the following variables is NOT a component of the SINS criteria?

Explanation

The Spinal Instability Neoplastic Score (SINS) consists of six components: Spine location (junctional vs. mobile vs. rigid), Pain (mechanical), Bone lesion type (lytic vs. blastic vs. mixed), Radiographic spinal alignment, Vertebral body collapse, and Posterolateral involvement of spinal elements. Patient life expectancy and tumor histology are crucial for overall decision-making (evaluated by systems like Tokuhashi or Tomita scores) but are NOT components of the SINS.

Question 29

A 48-year-old male presents with severe left lower extremity radicular pain. Examination reveals weakness in left ankle dorsiflexion, an intact Achilles reflex, and numbness over the medial aspect of the left lower leg. MRI reveals a far lateral (extraforaminal) disc herniation at the L4-L5 level. Which nerve root is most likely being compressed?

Explanation

A far lateral (extraforaminal) disc herniation at the L4-L5 level compresses the exiting L4 nerve root. In contrast, a paracentral disc herniation at the L4-L5 level typically spares the exiting L4 root and compresses the traversing L5 nerve root. The clinical picture described (ankle dorsiflexion weakness, medial leg numbness) matches an L4 radiculopathy.

Question 30

During posterior spinal fusion for Adolescent Idiopathic Scoliosis, following rod derotation, the neurophysiologist reports an 85% unilateral decrease in motor evoked potentials (MEPs). Somatosensory evoked potentials (SSEPs) remain stable. What is the most appropriate initial management?

Explanation

A significant drop in MEPs (>80% or loss of waveforms) with intact SSEPs suggests anterior spinal cord ischemia or impending cord stretch injury involving the corticospinal tracts. The immediate response should be to optimize hemodynamics by increasing MAP to >90 mmHg, verify no technical issues with monitoring, and release the surgical correction/distraction. Administering a bolus of propofol would further suppress MEP signals, as MEPs are highly sensitive to inhalational and intravenous anesthetics.

Question 31

In the Lenke Classification system for Adolescent Idiopathic Scoliosis, the lumbar spine modifier is determined by the relationship of the Center Sacral Vertical Line (CSVL) to the apical lumbar vertebra. Which of the following defines a Lenke Lumbar Modifier B?

Explanation

The Lenke Lumbar Modifiers are: A) CSVL passes between the pedicles of the apical lumbar vertebra. B) CSVL falls between the medial border of the pedicle and the lateral margin of the apical vertebral body. C) CSVL falls completely lateral to the lateral margin of the apical vertebral body. Modifier B indicates a structural but mild lumbar curve.

Question 32

A 45-year-old immigrant presents with progressive mid-back pain, low-grade fevers, and night sweats. Radiographs reveal a sharp angulation (gibbus deformity) at T9-T10. MRI demonstrates anterior vertebral body destruction with subligamentous spread across three levels and relatively preserved intervertebral disc spaces. What is the most likely diagnosis?

Explanation

Tuberculous spondylitis (Pott's disease) characteristically involves the anterior aspect of the vertebral bodies, spreads beneath the anterior longitudinal ligament (subligamentous spread) to involve multiple contiguous levels, and paradoxically spares the intervertebral discs until late in the disease process. Pyogenic spondylodiscitis (e.g., S. aureus) typically destroys the intervertebral disc early. A gibbus deformity is a classic sign of the resulting anterior wedge collapse in TB spine.

Question 33

A 22-year-old male is involved in a motor vehicle accident and diagnosed with a Levine-Edwards Type IIA Hangman's fracture (traumatic spondylolisthesis of the axis). Imaging shows an oblique fracture through the pars interarticularis with severe angulation and minimal anterior translation. What is the pathomechanism of this specific fracture type and the appropriate non-operative treatment?

Explanation

Levine-Edwards Type IIA Hangman's fractures are characterized by severe angulation with minimal translation and an oblique fracture line from anterior-inferior to posterior-superior. The mechanism is flexion-distraction. Application of cervical traction is contraindicated as it will distract the fracture fragments and worsen the deformity. The correct treatment is application of a Halo vest under gentle compression and slight extension.

Question 34

Which of the following clinical scenarios is an absolute indication for emergent surgical decompression in a patient with a spinal epidural abscess?

Explanation

Acute or progressive neurological deficit (such as progressing weakness or cauda equina syndrome) is an absolute indication for emergent surgical decompression in the setting of a spinal epidural abscess. Patients with no neurological deficits or only radicular pain can often be trialed on medical management (IV antibiotics). Patients with complete paralysis present for >48-72 hours have an extremely poor prognosis for recovery, making the benefit of emergency surgery highly questionable.

Question 35

During the neurological examination of a 60-year-old patient with suspected Cervical Spondylotic Myelopathy (CSM), you tap the brachioradialis tendon near the wrist. Instead of forearm flexion and supination, you observe spontaneous flexion of the patient's fingers. What is this clinical sign called and what level of the cervical spine does it implicate?

Explanation

The inverted radial (or brachioradialis) reflex is highly specific for Cervical Spondylotic Myelopathy at the C5-C6 level. Tapping the brachioradialis tendon typically elicits a C6 reflex arc (elbow flexion/supination). If the C6 anterior horn cells are damaged (LMN lesion) while the cord is compressed above the C8 level (UMN lesion), the typical reflex is absent, but hyperreflexia of the C8 distribution (finger flexors) is triggered instead. Hoffmann sign is generalized UMN, Wartenberg's is ulnar nerve/myelopathy intrinsic weakness.

Question 36

A 68-year-old male with type 2 diabetes presents with neck stiffness. Radiographs show flowing ossification along the anterolateral aspect of five contiguous cervical and thoracic vertebrae. Disc heights are preserved, and there is no evidence of sacroiliac joint ankylosis. Which of the following is true regarding this patient's condition?

Explanation

The clinical picture describes Diffuse Idiopathic Skeletal Hyperostosis (DISH). The classic Resnick and Niwayama criteria for DISH include: 1. Flowing ossification along the anterolateral aspect of at least 4 contiguous vertebrae. 2. Preservation of intervertebral disc height. 3. Absence of apophyseal joint bony ankylosis or sacroiliac joint erosion/sclerosis. Unlike Ankylosing Spondylitis, DISH is not associated with HLA-B27, lacks SI joint involvement, does not erode discs, and does not respond to immunosuppressants.

Question 37

Which of the following is the most classic demographic and anatomical presentation for degenerative spondylolisthesis versus isthmic spondylolisthesis?

Explanation

Degenerative spondylolisthesis classically occurs in older females (e.g., >50 years old), most frequently at the L4-L5 level, due to facet joint osteoarthritis and ligamentum flavum hypertrophy. Isthmic spondylolisthesis (secondary to a pars interarticularis defect) most classically presents in adolescents or young adults (frequently athletes involving repetitive hyperextension, like gymnasts), predominantly at the L5-S1 level.

Question 38

A 70-year-old male with known cervical stenosis falls forward and strikes his chin, forcefully hyperextending his neck. He presents with severe bilateral upper extremity weakness (motor strength 2/5) but is able to move his lower extremities well against gravity (motor strength 4/5). The disproportionate upper extremity weakness is due to injury to which aspect of the spinal cord?

Explanation

Central Cord Syndrome commonly occurs following a hyperextension injury in a patient with pre-existing cervical spondylosis. The injury preferentially damages the central portion of the cord. In the lateral corticospinal tract (the primary descending motor pathway), the fibers controlling the upper extremities are located medially, while the fibers controlling the lower extremities and sacral regions are located laterally. Thus, central cord edema/damage disproportionately affects the medially located cervical motor fibers.

Question 39

A 76-year-old female with osteoporosis suffers a T12 compression fracture. She has been treated conservatively with bracing, analgesics, and activity modification. Six weeks later, she still requires narcotic pain medication to ambulate. MRI is ordered to evaluate for percutaneous vertebroplasty. Which MRI sequence finding most strongly correlates with successful pain relief following vertebroplasty?

Explanation

The presence of bone marrow edema (hyperintensity) on Short Tau Inversion Recovery (STIR) or T2-weighted MRI indicates an acute or subacute, non-healed fracture. This finding strongly correlates with a favorable clinical outcome (pain relief) following cement augmentation procedures like vertebroplasty or kyphoplasty. Conversely, if the vertebral body shows no edema, the fracture is considered healed, and vertebroplasty will not relieve the patient's mechanical back pain.

Question 40

A patient arrives in the trauma bay following a motorcycle collision. Neurological examination reveals absent motor function below the level of the umbilicus. However, the patient can feel light touch and pinprick around the perianal area (S4-S5), and voluntary anal contraction is absent. According to the ASIA Impairment Scale, how is this injury classified?

Explanation

The ASIA Impairment Scale evaluates the completeness of a spinal cord injury. ASIA A = Complete (no sensory or motor function preserved in sacral segments S4-S5). ASIA B = Sensory incomplete (sensory but not motor function is preserved below the neurological level and includes the sacral segments S4-S5). ASIA C = Motor incomplete (motor function is preserved, and more than half of key muscles below the neurological level have a muscle grade < 3). ASIA D = Motor incomplete (at least half of key muscles below level have grade ≥ 3). The presence of sacral sensation without motor function defines ASIA B.

Question 41

An 82-year-old female presents after a ground-level fall with neck pain. CT shows a Type II odontoid fracture with 2mm of posterior displacement. Neurologic examination is completely intact. What is the most appropriate initial management for this patient?

Explanation

In elderly patients with a Type II odontoid fracture, halo vest immobilization has an unacceptably high morbidity and mortality rate. A rigid cervical collar is the preferred initial management for minimally displaced fractures in frail or elderly demographics.

Question 42

A 60-year-old male with long-standing ankylosing spondylitis presents after a minor fall. He has severe lower cervical pain but is neurologically intact. Standard 3-view cervical radiographs are unremarkable. What is the most appropriate next step in management?

Explanation

Patients with ankylosing spondylitis are at high risk for highly unstable extension-distraction fractures even from minor trauma. Because standard radiographs frequently miss these injuries due to altered anatomy, a CT scan of the entire cervical spine is mandatory.

Question 43

A 70-year-old male with known cervical stenosis presents after a hyperextension injury. He exhibits significant bilateral upper extremity weakness, particularly hand intrinsic wasting, with relatively preserved lower extremity strength and intact bowel/bladder function. What is the most likely diagnosis?

Explanation

Central cord syndrome classically occurs following a hyperextension injury in patients with preexisting cervical spondylosis. It presents with disproportionately greater motor impairment in the upper extremities compared to the lower extremities.

Question 44

A 55-year-old diabetic male presents with severe back pain, fevers, and progressive bilateral lower extremity weakness over the past 12 hours. MRI reveals a ventral epidural abscess at L3-L4 compressing the cauda equina. What is the most appropriate immediate management?

Explanation

A spinal epidural abscess presenting with progressive neurologic deficits is a surgical emergency. Emergent surgical decompression and debridement must be performed to prevent irreversible neurologic damage.

Question 45

A 20-year-old female is involved in a high-speed motor vehicle collision while wearing a lap belt. Radiographs reveal a transverse fracture through the L2 vertebral body, pedicles, and spinous process. Which of the following associated injuries must be most highly suspected?

Explanation

A Chance fracture is a flexion-distraction injury strongly associated with lap belt use. Approximately 50% of these patients will have a concurrent intra-abdominal injury, most commonly involving the bowel or mesentery.

Question 46

A 50-year-old male presents with progressive clumsiness in his hands and an unsteady gait. CT demonstrates a continuous band of dense ossification along the posterior aspect of the C3-C6 vertebral bodies. The ossified mass occupies 65% of the spinal canal, and his cervical spine is lordotic. Which surgical approach is generally preferred?

Explanation

For Ossification of the Posterior Longitudinal Ligament (OPLL) occupying >50-60% of the canal or involving more than 3 levels in a lordotic spine, a posterior approach (laminectomy and fusion or laminoplasty) is preferred. Anterior corpectomy carries an unacceptably high risk of dural tear and cord injury in severe OPLL.

Question 47

A 62-year-old female with a history of breast cancer presents with intractable back pain. MRI shows a metastatic lesion at T8 with spinal cord compression. Her Tokuhashi score is calculated to be 13. What is the most appropriate treatment recommendation?

Explanation

A Tokuhashi score of 12-15 indicates an expected survival prognosis of greater than 1 year. These patients are optimal candidates for excisional surgery or aggressive decompression and stabilization to improve neurologic outcomes and quality of life.

Question 48

A 14-year-old female gymnast complains of chronic low back pain. Radiographs demonstrate a Grade II L5-S1 isthmic spondylolisthesis. After 6 months of failed physical therapy and bracing, what is the most appropriate surgical treatment?

Explanation

For a symptomatic Grade II isthmic spondylolisthesis in an adolescent that has failed conservative care, an L5-S1 posterolateral fusion in situ is the standard of care. Pars repair is typically reserved for L4 or higher and only for Grade 0-I slips.

Question 49

A 15-year-old male presents with progressive upper back rounding. Standing lateral radiographs show a thoracic kyphosis of 65 degrees and anterior wedging of 3 consecutive vertebrae of 6 degrees each. What is the most appropriate initial management?

Explanation

This patient meets the classic radiographic criteria for Scheuermann's kyphosis. For a skeletally immature patient with a flexible curve between 50 and 75 degrees, extension bracing combined with physical therapy is the recommended first-line treatment.

Question 50

A 40-year-old male presents with severe low back pain, bilateral sciatica, and perianal numbness. A bladder scan shows a post-void residual volume of 400 mL. MRI reveals a massive L4-L5 disc herniation. What is the most critical factor in predicting his functional recovery?

Explanation

In Cauda Equina Syndrome, the timing of surgical decompression is the most critical factor determining neurologic and urologic recovery. Surgery should ideally be performed within 24 to 48 hours of symptom onset to minimize the risk of permanent bladder and bowel dysfunction.

Question 51

A 25-year-old male is placed in a halo vest for a C2 fracture. One week later, he complains of double vision. On examination, he is unable to abduct his left eye. Which cranial nerve is most likely injured, and what is the presumed mechanism?

Explanation

Cranial nerve VI (abducens) palsy is a known complication of halo vest application, typically caused by excessive longitudinal traction stretching the nerve. It presents with an inability to abduct the affected eye, leading to diplopia.

Question 52

A 5-year-old boy is evaluated after a minor fall. His lateral cervical spine radiograph shows 3mm of anterior displacement of C2 on C3. The Swischuk line passes 1mm anterior to the anterior aspect of the C3 posterior arch. What is the correct interpretation?

Explanation

Pseudosubluxation of C2 on C3 is a normal physiologic finding in children up to age 8. A Swischuk line passing within 2mm (anterior or posterior) of the anterior aspect of the C3 spinous process confirms that the displacement is physiologic and benign.

Question 53

A 30-year-old male is involved in a motor vehicle collision. CT reveals bilateral pars interarticularis fractures of C2 with 4mm of anterior translation and severe angulation. According to the Levine-Edwards classification, this is a Type II fracture. What is the primary mechanism of injury?

Explanation

A Levine-Edwards Type II Hangman's fracture is typically caused by a hyperextension injury followed by rebound flexion. This combined mechanism disrupts the C2-C3 intervertebral disc and the posterior longitudinal ligament, leading to significant angulation.

Question 54

A 14-year-old female with Adolescent Idiopathic Scoliosis has a main thoracic curve of 55 degrees and a lumbar curve of 35 degrees. On lateral bending radiographs, the lumbar curve bends out to 15 degrees. According to the Lenke classification, what type of curve is this?

Explanation

In the Lenke classification, a minor curve that corrects to less than 25 degrees on side-bending radiographs is considered non-structural. Since the lumbar curve bends out to 15 degrees, it is non-structural, making this a Lenke 1 (Main Thoracic) curve pattern.

Question 55

A 72-year-old male presents with significant neck stiffness. Radiographs demonstrate flowing ossification along the anterolateral aspect of 5 contiguous lower cervical and upper thoracic vertebrae, with preserved disc heights and no sacroiliac joint involvement. What is the most likely diagnosis?

Explanation

Diffuse Idiopathic Skeletal Hyperostosis (DISH) is characterized by flowing anterolateral ossification of at least 4 contiguous vertebral bodies. Unlike Ankylosing Spondylitis, DISH features preserved disc heights and classically spares the sacroiliac joints.

Question 56

A 45-year-old male presents with severe acute low back pain, bilateral lower extremity radicular pain, and new-onset urinary retention. Examination reveals perineal anesthesia and decreased anal sphincter tone. To maximize the likelihood of functional sphincter recovery, surgical decompression should ideally be performed within what timeframe?

Explanation

Cauda equina syndrome is a surgical emergency. Literature suggests that decompression within 48 hours of symptom onset maximizes the likelihood of significant bowel and bladder functional recovery.

Question 57

A 78-year-old female sustains a fall and is diagnosed with a displaced Type II odontoid fracture. She has a history of mild COPD and hypertension. Which of the following management strategies offers the highest rate of bony union for this specific patient?

Explanation

In elderly patients (age > 70) with displaced Type II odontoid fractures, conservative management (halo or collar) has a high nonunion rate and significant morbidity. Posterior C1-C2 instrumentation and fusion offers the highest union rates and functional outcomes.

Question 58

In the surgical management of Adult Spinal Deformity, restoring sagittal balance is a primary goal. Which of the following pelvic parameters is a fixed, position-independent morphological measurement of the pelvis?

Explanation

Pelvic incidence is a fixed morphological parameter that dictates the necessary amount of lumbar lordosis (LL = PI ± 9 degrees). Pelvic tilt and sacral slope are dynamic parameters that change with patient positioning.

Question 59

A 28-year-old female presents with severe right leg radicular pain. MRI reveals a far-lateral (extraforaminal) disc herniation at the L4-L5 level. Which nerve root is most likely compressed, and what is the expected motor deficit?

Explanation

A far-lateral (extraforaminal) disc herniation at L4-L5 compresses the exiting L4 nerve root. L4 compression classically presents with weakness in knee extension (quadriceps) and a diminished patellar reflex.

Question 60

A 45-year-old male presents with severe right leg pain. Examination shows 4/5 weakness in right knee extension and a diminished patellar reflex. MRI reveals a far lateral disc herniation at the L4-L5 level. Which nerve root is most likely compressed?

Explanation

Far lateral (extraforaminal) disc herniations compress the exiting nerve root at the same level. Therefore, an L4-L5 far lateral disc herniation will compress the L4 nerve root, leading to knee extension weakness and a decreased patellar reflex.

Question 61

A 70-year-old male with known cervical spondylosis presents after a hyperextension injury. He has 2/5 motor strength in his upper extremities and 4/5 in his lower extremities, with spotty sensory loss. What is the most likely diagnosis?

Explanation

Central cord syndrome typically occurs after a hyperextension injury in a patient with pre-existing cervical stenosis. It is characterized by disproportionately greater motor impairment in the upper extremities compared to the lower extremities.

Question 62

A 78-year-old female sustains a Type II odontoid fracture after a ground-level fall. Displacement is 2 mm, and she is neurologically intact. Given her age and comorbidities, what is the most appropriate initial management?

Explanation

In elderly patients (>65 years) with Type II odontoid fractures, rigid collar immobilization is preferred over a halo vest due to the high morbidity and mortality associated with halo placement. Surgery is reserved for nonunions or highly displaced fractures.

Question 63

A 22-year-old female wearing a lap-belt during a high-speed motor vehicle collision presents with a seatbelt sign across her abdomen. Spine radiographs reveal a flexion-distraction (Chance) fracture at L1. What associated injury must be urgently ruled out?

Explanation

Chance fractures are flexion-distraction injuries commonly caused by seatbelts acting as a fulcrum. They carry a high risk (up to 50%) of associated intra-abdominal injuries, particularly hollow viscus (bowel) injuries.

Question 64

A 55-year-old male with long-standing ankylosing spondylitis presents with neck pain after a minor fall. He is neurologically intact. Initial lateral cervical spine X-rays are reported as normal. What is the most appropriate next step in management?

Explanation

Patients with ankylosing spondylitis are at high risk for highly unstable "chalk stick" fractures even from minor trauma. A normal X-ray does not rule out a fracture; advanced imaging (CT or MRI) is mandatory to evaluate for occult fractures or epidural hematomas.

Question 65

In evaluating a patient with adult spinal deformity, achieving appropriate sagittal balance is a primary surgical goal. Which of the following spinopelvic parameters is morphological and remains fixed regardless of patient positioning?

Explanation

Pelvic incidence (PI) is a fixed morphological parameter unique to each individual's pelvic anatomy. As the pelvis retroverts or anteverts to compensate for deformity, pelvic tilt and sacral slope change, but PI remains constant.

Question 66

A 50-year-old diabetic male presents with severe back pain, fevers, and progressive lower extremity weakness. MRI reveals an L3-L4 ventral epidural abscess. Laboratory tests show elevated ESR and CRP. What is the definitive management?

Explanation

The presence of a progressive neurologic deficit in the setting of a spinal epidural abscess is an absolute indication for urgent surgical decompression, typically via laminectomy and debridement. IV antibiotics alone are reserved for patients without neurologic deficits.

Question 67

A 14-year-old gymnast presents with chronic mechanical low back pain. Radiographs demonstrate an isthmic L5-S1 spondylolisthesis with 60% anterior translation. What is the Meyerding grade and recommended treatment?

Explanation

Meyerding Grade III corresponds to 50-75% translation. In pediatric patients, high-grade slips (>50%) have a high risk of progression and neurologic compromise, warranting surgical stabilization with posterior spinal fusion.

Master Orthopedic Spine Cases: Sharpen Your Diagnostic Skills

Orthopedic Spine Review | Dr Hutaif Spine Surgery Revie -...

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