Question 1

A 28-year-old woman complains of pain and numbness in her lower legs bilaterally for approximately 2 months following strenuous moving of furniture. She now states that she has not voided in the past 48 hours and that her abdomen area is markedly distended. What diagnostic test must be performed in order to support the suspected diagnosis:

Explanation

Based on history and physical examination, the suspected diagnosis is cauda equina syndrome. This potential surgical emergency requires immediate spinal imaging. A magnetic resonance imaging of the lumbosacral spine is the most appropriate test.

Question 2

On physical examination, the umbilicus is a superficial landmark for the bifurcation of the aorta into the common iliac arteries and overlies this disk space:

Explanation

The umbilicus is a superficial landmark that often lies over the anterior L3/L4 disk space, which is the location of the aortic bifurcation into the common iliac arteries. Below this arterial division, in lean individuals, one can palpate the anterior bodies of L4, L5, and S1.

Question 3

A 35-year-old woman has been complaining of severe unrelenting mid to low back pain for the past 5 months. Conservative management, consisting of bed rest and nonsteroidal anti-inflammatory drugs (NSAIDs), has not decreased the intensity of her symptoms. She immigrated to the United States from Vietnam 6 months ago. Based on the sagittal magnetic resonance image below, the next step in her management is:

Orthopedic Prometric Exam Chapter 3 Image

Explanation

It is prudent to determine the underlying etiology of this lesion. Tuberculous spondylitis is increasing in frequency and must be suspected in people who emigrate from countries where tuberculosis is endemic. A biopsy of the region must be obtained in order to make the diagnosis of tuberculosis accurately or any other infectious and noninfectious causative agent in order to determine proper management.

Question 4

What is the most common sequence of steps performed during a midline open disectomy in the treatment and excision of a herniated posterolateral lumbar disk:

Explanation

The traditional surgery for the excision of a herniated posterolateral lumbar disk is by means of a midline incision. This procedure is then performed in a stepwise fashion: The paraspinal musculature is stripped from the lamina of the vertebra; the ligamentum flavum is then excised; portions of the superior and inferior lamina are removed; and the nerve root and dural sac are identified and carefully retracted. This is followed by excision of the herniated disk material and wound closure.

Question 5

On physical examination, a patient with a weak extensor hallucis longus muscle might be expected to have a far-lateral disk herniation at what level in the spine:

Explanation

A far-lateral disk herniation in the lumbar spine often compromises the more proximal, or exiting, nerve root and not the more distal, or traversing, nerve root most typically affected in a posterolateral disk herniation. Therefore, a far-lateral disk herniation at the L5 - S1 level could irritate the L5 nerve root, which would affect the extensor hallucis longus muscle.

Question 6

One traditional surgery performed for the treatment of a symptomatic posterolateral lumbar disk herniation is a partial laminectomy and lumbar disk excision by means of a midline incision. What is the long-term (>2 years) success rate for relief of both leg and low back pain, respectively:

Explanation

The success rate following a partial laminectomy and lumbar disk excision for a posterolateral herniated disk for relief of both leg and low back pain is predictable at 93% and 80%, respectively.

Question 7

A 38-year-old man injured his neck and spinal cord 6 months ago as a result of a motorcycle accident. He is now a C 6 quadriplegic. He wants to know how his sexual function will be affected by his condition. The patient should be informed that:

Explanation

With this type of spinal cord injury, it is possible to have an erection with external stimulation; however, ejaculation would have to be facilitated by electrical stimulation or vibratory means.

Question 8

When testing the range of motion in the lumbar spine, which maneuver involves stretching of the interspinous and supraspinous ligaments, ligamentum flavum, and posterior longitudinal ligament while relaxing the anterior longitudinal ligament:

Explanation

Flexion of the lumbar spine creates stretching or tension of the posterior spinal structures including the interspinous and supraspinous ligaments, ligamentum flavum, and posterior longitudinal ligament. Flexion also allows relaxation of the anterior longitudinal ligament. This is often elicited by having a patient bend forward in attempt to touch the floor with the fingertips. If the patient cannot touch the floor, the distance from the floor to fingertips is measured in fingerbreadths or inches.

Question 9

A 22-year-old woman sustained an injury to her low back 1 year ago while playing rugby. She now complains of excruciating low back pain with numbness and tingling into her left buttock. This pain is affecting her daily living activities. The patient underwent 6 months of conservative management consisting of restriction of activities, physical therapy, and anti- inflammatory medication with little relief. Based on the image below, the next appropriate step in the management of this patient is:

Orthopedic Prometric Exam Chapter 3 Image

Explanation

The patient has an L5/S1 spondylysis with a grade 1 spondylolisthesis. This patient has undergone a sufficient attempt at conservative management with continued unrelenting low back pain. The next most appropriate step in the management of this condition is a posterolateral fusion at the L5/S1 level with autologous bone graft.

Question 10

When performing a neurological examination, if a surgeon has a patient resist thigh adduction against resistance, the surgeon is testing which nerve(s):

Explanation

The obturator nerve innervates most of the hip adductor group, which consists of neurologic levels L2, L3, and L4.

Question 11

A 72-year-old man comes to the office complaining of low back and thigh pain that has been progressively getting worse over the years. The pain now bothers him during weather changes. The patient tells you that his pain is worse with standing and walking for long periods. However, leaning forward and sitting alleviates his discomfort. The patient denies any bladder or bowel complaints. This patient most likely has:

Explanation

This patient is presenting with the hallmark symptoms of lumbar spinal stenosis, which consists of increased back and thigh pain with walking or standing with relief of the symptoms by leaning forward or sitting down. This patient denies any bladder or bowel dysfunction that makes cauda equina syndrome unlikely. Although urinary dysfunction is uncommon in spinal stenosis, it can occur in approximately 3% to 4% of cases.

Question 12

A positive straight-leg raise sign:

Explanation

A positive straight-leg raise sign occurs when the sciatic nerve is placed under tension or is stretched reproducing a radiculopathy. It is also suggestive of inflammation around the nerve root, hence it is a good predictor of the successful relief of symptoms from surgical decompression. Additionally, a positive straight-leg raise sign is a relatively sensitive test for detecting a lumbar disk herniation, but it is not specific. Because the sign is not specific, it does not necessarily correspond to trauma or injury.

Question 13

What physical examination maneuvers listed below check the status of the L4 neurologic level:

Explanation

Sensation on the medial side of the ankle, the patellar tendon reflex, and plantar inversion are associated with the L4 neurologic level. Sensation on the lateral side of the ankle and the Achilles tendon reflex are associated with the S1 neurologic level.

Question 14

In describing idiopathic scoliosis, there are several terms given to curve patterns on radiographs to describe the specific type of spinal deformity present. Which term best describes an area of the spine with a lateral curve that lacks normal flexibility noted radiographically by its failure to demonstrate segmental mobility or correction on supine side-bending radiographs:

Explanation

The above question is describing a structural (nonflexible) curve. A primary curve is the earliest of several curves that may eventually develop. The term major curve is used to designate the largest structural curve. The minor curve refers to the smallest structural curve and is usually more flexible than the major curve. The compensatory curve is located above or below a major curve to attempt to maintain normal body alignment.

Question 15

When performing a physical examination, if running the pointed edge of a reflex hammer along the crest of a patient's tibia causes extension of the great toe while the remaining toes splay or plantarflex, this finding would indicate:

Explanation

An Oppenheim test is considered positive when running a pointed object along a patient's tibial crest elicits splaying or plantarflexion of the smaller toes with great toe extension. An Oppenheim test is considered negative when this reaction is not present. A Babinski reflex is present when running a pointed object across the plantar surface of a patient's foot elicits splaying or plantarflexion of the toes with extension of the great toe. A Babinski reflex is considered absent when the toes either do not move or all five toes flex and/or bunch up in response to the stimulus.

Question 16

When trying to distinguish hamstring tightness/discomfort from sciatic pain/radiculopathy, surgeons can perform a straight-leg raise test on the affected side until the point at which the patient develops discomfort. This is followed by slightly lowering the affected extremity. While holding the patient's leg in this position, what maneuver could be performed in order to help reproduce true sciatic pain:

Explanation

Dorsiflexion of the foot, known as Braggard test, adds additional tension or stretch to the sciatic nerve and may help reproduce the sciatic pain/radiculopathy.

Question 17

Beevor sign is a physical examination maneuver that tests the integrity of the rectus abdominus muscles that are segmentally innervated by the anterior primary divisions of the T5-T12/L1 nerve roots. When performing this test, the patient is asked to perform a partial sit-up. A positive Beevor sign is indicated by:

Explanation

When performing a sit-up, umbilical deviation due to abnormal contraction of the rectus musculature indicates either a partial or complete loss of segmental innervation to a portion of the rectus abdominus and/or paraspinal musculature. It is frequently seen in patients with certain neurological disorders such as meningomyelocele and poliomyelitis.

Question 18

Which anatomic structure(s) may be the cause of referred pain to the lumbar spine region:

Explanation

The hip, rectum, and pelvis may refer pain to the lumbar spine region. In order to perform a complete physical examination, a rectal exam is recommended on all patients with pain in the lumbar spine region.

Question 19

The following nonoperative treatments have not been proven effective in the early acute stage (2 weeks to 3 months) of low back pain:

Explanation

Nonsteroidal anti-inflammatory drugs have been shown effective and are frequently used during the acute phase of low back pain. Their main effect is to alleviate soft tissue inflammation that is often present in the early phase. Patient questionnaires have identified bed rest as among the most frequently prescribed treatments for lower back pain. It has been shown that bed rest results in reduced intradiskal pressure that occurs in the supine position. Anesthetic/corticosteriod injections are widely advocated for the treatment of low back pain and can be administered along nerve roots, into the sacroiliac joints, intervertebral disks, paraspinal soft tissues, and the epidural space or intrathecally for many conditions. However, there is no evidence that intraspinal steroids have an effective role in the acute management of low back pain.

Question 20

A 32-year-old woman is diagnosed on magnetic resonance imaging with a far-lateral disk herniation at the L3/L4 level causing radiating right lower extremity discomfort across the anterior aspect of her knee with no motor or reflex abnormalities. Which of the following nerve roots is most likely affected:

Explanation

A far-lateral or foraminal disk herniation often affects the exiting or more proximal nerve root. The traversing or more distal nerve root is typically affected from a posterolateral disk herniation. In this case, the patient has a far-lateral disk herniation at the L3/L4 level resulting in L3 nerve root symptomatology.

Question 21

A 45-year-old man presents with sharp pain radiating down his right posterior thigh and calf to the plantar surface of his foot. On physical examination, he demonstrates a weakened Achilles tendon reflex and decreased sensation over the lateral aspect of his foot. Which nerve root is most likely compressed?

Explanation

The S1 nerve root supplies sensation to the lateral foot, motor function for plantar flexion, and the reflex arc for the Achilles tendon. A posterolateral disc herniation at L5-S1 typically compresses the traversing S1 root.

Question 22

A 72-year-old man with a known history of severe cervical spondylosis falls forward and strikes his chin. He is brought to the emergency department presenting with severe weakness in his upper extremities, particularly the hands, but retains the ability to move his legs against gravity. Which spinal cord syndrome does this presentation most likely represent?

Explanation

Central cord syndrome classically occurs in elderly patients with pre-existing cervical spondylosis following a hyperextension injury. It disproportionately affects the medially located cervical motor tracts, leading to greater weakness in the upper extremities than the lower extremities.

Question 23

A 55-year-old diabetic patient presents with a 2-week history of progressively worsening mid-back pain, low-grade fever, and a recent onset of bilateral lower extremity weakness. What is the most common causative organism for the suspected diagnosis?

Explanation

The classic clinical triad of a spinal epidural abscess consists of back pain, fever, and neurologic deficit. Staphylococcus aureus is the most common causative organism overall.

Question 24

A 40-year-old man with a 15-year history of ankylosing spondylitis presents to the emergency department after a minor trip and fall at home. He complains of new-onset neck pain but has no neurologic deficits. Plain radiographs of the cervical spine are heavily obscured by his shoulders. What is the next best step in management?

Explanation

Patients with ankylosing spondylitis have highly rigid spines that are extremely susceptible to fractures, even from trivial trauma. A CT scan of the cervical spine is mandatory in this population to rule out occult fractures when plain films are inadequate or negative.

Question 25

A 25-year-old man dives into a shallow pool and sustains a Jefferson burst fracture of the atlas (C1). According to the rule of Spence, what is the threshold of total combined overhang of the C1 lateral masses on an open-mouth odontoid radiograph that suggests a rupture of the transverse atlantal ligament?

Explanation

A total combined overhang of the C1 lateral masses on the C2 articular facets greater than 6.9 mm on an AP open-mouth radiograph implies a highly probable rupture of the transverse atlantal ligament, rendering the fracture unstable.

Question 26

A 65-year-old male presents with bilateral leg pain that worsens with walking and improves when leaning forward on a shopping cart. Based on the likely diagnosis shown in the representative MRI, what is the most appropriate surgical intervention if prolonged conservative management fails?

Explanation

The clinical presentation is classic for neurogenic claudication due to lumbar spinal stenosis. Lumbar laminectomy (decompression) is the gold standard surgical treatment for symptomatic central canal stenosis refractory to conservative measures.

Question 27

A 12-year-old premenarchal girl is diagnosed with adolescent idiopathic scoliosis. Her physical examination reveals a right thoracic prominence. Radiographs show a right thoracic curve with a Cobb angle of 34 degrees and a Risser stage of 1. What is the most appropriate management?

Explanation

Bracing is indicated for skeletally immature patients (Risser 0-2, premenarchal) with an idiopathic curve between 25 and 45 degrees. A TLSO brace effectively alters the natural history of curve progression in this high-risk population.

Question 28

A 19-year-old female is involved in a high-speed motor vehicle collision while wearing only a lap belt. She sustains a Chance fracture of L2. Which of the following associated injuries must be highly suspected and ruled out?

Explanation

Chance fractures are flexion-distraction injuries highly associated with lap belt use. Approximately 40-50% of these patients have concomitant intra-abdominal injuries, particularly to hollow viscous organs like the small bowel.

Question 29

A 32-year-old male presents after a motor vehicle accident with neck pain. Neurological examination is intact. Based on the lateral cervical spine radiograph below, what is the most appropriate initial management for a Type II traumatic spondylolisthesis of the axis?

Explanation

Type II traumatic spondylolisthesis of the axis (Hangman's fracture) with significant angulation or translation is typically managed with Halo immobilization. Type I fractures are generally stable and can be managed with a rigid cervical collar.

Question 30

A 54-year-old diabetic male presents with 3 weeks of worsening back pain, fever, and elevated ESR. Sagittal MRI is provided below. Blood cultures are pending. Neurologically he is intact. What is the most appropriate next step in management?

Explanation

In a hemodynamically stable patient with pyogenic spondylodiscitis and no neurologic deficit, establishing a microbiologic diagnosis via CT-guided biopsy is indicated before initiating antibiotics. Empiric antibiotics should only be started immediately if the patient is septic or has profound neurologic decline.

Question 31

A 45-year-old male presents with severe neck pain radiating down his left arm. Physical exam reveals weakness in wrist flexion and finger extension, with diminished triceps reflex. Sensation is decreased in the middle finger. Which nerve root is most likely compressed?

Explanation

Compression of the C7 nerve root classically causes weakness in the triceps, wrist flexors, and finger extensors. It also results in a diminished triceps reflex and numbness primarily affecting the middle finger.

Question 32

A 68-year-old female complains of bilateral leg pain and heaviness that worsens after walking two blocks. The pain is relieved when she sits or leans forward over a shopping cart. What is the most likely anatomic cause of her symptoms?

Explanation

Neurogenic claudication from lumbar spinal stenosis is typically caused by degenerative changes including ligamentum flavum hypertrophy, facet arthropathy, and disc bulging. Symptoms are classically relieved by lumbar flexion, which increases the spinal canal volume.

Question 33

A 25-year-old male sustains a severe hyperflexion injury to his thoracic spine. On examination, he has no motor function below the umbilicus and no sensation except for intact perianal sensation (S4-S5). There is no voluntary anal sphincter contraction. What ASIA impairment scale grade does this represent?

Explanation

ASIA B designates an incomplete spinal cord injury where sensory function is preserved below the neurologic level, including sacral segments S4-S5, but no motor function is preserved. Sacral sparing is the hallmark of an incomplete spinal cord injury.

Question 34

A 19-year-old female is involved in a high-speed frontal motor vehicle collision while wearing a lap belt. Radiographs show a flexion-distraction injury (Chance fracture) of L2. Which of the following associated injuries is most critical to rule out?

Explanation

Chance fractures are flexion-distraction injuries highly associated with intra-abdominal trauma, particularly hollow viscus injuries like small bowel perforation. Careful abdominal evaluation is mandatory in all patients presenting with this fracture pattern.

Question 35

In a patient with long-standing rheumatoid arthritis undergoing pre-operative evaluation for a total hip arthroplasty, flexion-extension cervical radiographs are obtained. Which finding would most strongly indicate the need for prophylactic cervical spine stabilization?

Explanation

A Posterior Atlantodental Interval (PADI) of 14 mm or less indicates impending cord compression and correlates better with neurologic deficit than ADI. PADI < 14 mm is a critical threshold often prompting surgical intervention in rheumatoid atlantoaxial subluxation.

Question 36

A 75-year-old male with known cervical spondylosis falls forward, striking his chin. He presents with severe bilateral upper extremity weakness, particularly in the hands, but retains near-normal strength in his lower extremities. Pain and temperature sensation are diminished in a cape-like distribution. What is the most likely diagnosis?

Explanation

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

Question 37

A 22-year-old male suffers a stab wound to the right side of his back at the T8 level. Examination reveals loss of ipsilateral motor function and proprioception below the lesion, along with contralateral loss of pain and temperature sensation. Which spinal cord tract is responsible for the patient's loss of pain and temperature sensation?

Explanation

Brown-Sequard syndrome results from spinal cord hemisection. The spinothalamic tract carries pain and temperature sensation; because these fibers cross early in the spinal cord, damage to the tract results in contralateral sensory loss below the lesion.

Question 38

A 60-year-old female presents with insidious onset of persistent mid-thoracic back pain, worsened by recumbency. Laboratory results show hypercalcemia and elevated total protein. Radiographs reveal a lytic lesion in the T7 vertebral body. Which of the following is the most likely diagnosis?

Explanation

Multiple myeloma is the most common primary malignancy of bone in adults. It classically presents with bone pain, hypercalcemia, lytic bone lesions, and elevated serum protein due to monoclonal gammopathy.

Question 39

According to the Denis three-column theory of the spine, which of the following structures is considered part of the middle column?

Explanation

The middle column in the Denis classification consists of the posterior half of the vertebral body, the posterior annulus fibrosus, and the posterior longitudinal ligament. Disruption of the middle column is the defining hallmark of a burst fracture.

Question 40

A 35-year-old construction worker falls from a height and sustains a burst fracture of L1. Neurological examination is completely normal. Which of the following radiographic findings would be an absolute indication for surgical stabilization rather than conservative management?

Explanation

Disruption of the posterior ligamentous complex (PLC) renders a thoracolumbar fracture highly unstable, dictating surgical stabilization. Degree of retropulsion alone without neurologic deficit or PLC injury does not absolutely mandate surgery.

Question 41

A 28-year-old male presents with chronic lower back pain and morning stiffness lasting longer than an hour. Radiographs show squaring of the lumbar vertebrae and syndesmophyte formation. He is at increased risk for which of the following cervical spine complications even with minor trauma?

Explanation

Patients with ankylosing spondylitis have a rigid, osteopenic spine that acts like a long bone, making it highly susceptible to fracture even from minor trauma. These fractures are frequently accompanied by extensive epidural hematomas due to the altered dural-bone relationship.

Question 42

A 45-year-old man presents with neck pain radiating down his right arm. Examination reveals weakness in right wrist extension and a diminished brachioradialis reflex. Which cervical nerve root is most likely compressed?

Explanation

A C5-C6 disc herniation compresses the C6 nerve root. This results in weakness of wrist extension and elbow flexion, along with a diminished brachioradialis reflex and numbness in the thumb and index finger.

Question 43

A 32-year-old weightlifter presents with acute lower back pain radiating to the dorsum of his left foot. He exhibits weakness in great toe extension but normal ankle plantar flexion and knee extension. A paracentral disc herniation at which level is most likely responsible?

Explanation

A paracentral disc herniation at L4-L5 typically compresses the traversing L5 nerve root. This manifests as weakness in extensor hallucis longus (EHL) and sensory deficits over the dorsum of the foot.

Question 44

A 68-year-old man complains of deteriorating handwriting and a feeling of imbalance when walking. Physical examination reveals a positive Hoffmann sign bilaterally and hyperreflexia in the lower extremities. What is the most appropriate initial diagnostic modality?

Explanation

The patient exhibits signs of cervical spondylotic myelopathy, including upper extremity clumsiness and upper motor neuron signs. An MRI of the cervical spine is the gold standard to evaluate spinal cord compression and signal changes.

Question 45

A 22-year-old woman is brought to the trauma bay after a high-speed motor vehicle collision where she was wearing a lap belt. She has severe localized back pain and an ecchymotic band across her abdomen.

What is the primary mechanism of injury for the suspected spinal fracture?

Explanation

A lap belt injury classically causes a flexion-distraction injury (Chance fracture) of the thoracolumbar spine. It involves tension failure of the anterior, middle, and posterior columns, requiring careful evaluation for associated visceral abdominal injuries.

Question 46

When placing a halo vest in a patient with an unstable cervical fracture, the anterior pins must be placed within a specific 'safe zone' to avoid nerve injury. Which nerve is most at risk if the anterior pins are placed too medially over the forehead?

Explanation

Anterior halo pins should be placed in the lateral one-third of the eyebrow to avoid the supraorbital and supratrochlear nerves. Medial placement risks injuring these nerves, causing forehead numbness or persistent pain.

Question 47

A 15-year-old female gymnast complains of persistent mechanical lower back pain. Lateral radiographs show a grade 1 anterolisthesis of L5 on S1. Oblique views demonstrate a 'Scotty dog with a collar' appearance. What is the initial treatment of choice?

Explanation

The patient has a symptomatic isthmic spondylolisthesis secondary to a pars interarticularis defect, common in adolescent athletes. Initial management for low-grade slips is non-operative, focusing on activity modification, physical therapy, and bracing.

Question 48

A 55-year-old man with long-standing ankylosing spondylitis experiences a mechanical fall from a standing height. He complains of new-onset severe lower neck pain but has no neurological deficits. Radiographs are obscured by his severe kyphotic deformity. What is the most appropriate next step?

Explanation

Patients with ankylosing spondylitis have rigid, osteopenic spines that are highly susceptible to unstable fractures even from minor trauma. A CT scan of the entire cervical spine is mandatory to detect occult fractures, as standard radiographs are frequently inadequate.

Question 49

A 72-year-old woman complains of bilateral leg cramping and heaviness after walking 2 blocks. The pain is rapidly relieved when she sits down or leans forward over a shopping cart, but it persists if she stands upright while stationary. Her pedal pulses are palpable. What is the most likely diagnosis?

Explanation

Neurogenic claudication secondary to lumbar spinal stenosis is classically exacerbated by lumbar extension (standing, walking) and relieved by flexion (sitting, leaning forward). The persistence of symptoms while standing stationary distinguishes it from vascular claudication.

Question 50

Which of the following parameters indicates the highest risk for curve progression in a 12-year-old female with adolescent idiopathic scoliosis?

Explanation

The risk of curve progression in adolescent idiopathic scoliosis is highest during the peak height velocity. A Risser grade of 0 combined with an open triradiate cartilage indicates significant remaining skeletal growth, placing the patient at maximum risk.

Question 51

A 48-year-old intravenous drug user presents with a 1-week history of severe mid-back pain, fever, and progressive bilateral leg weakness. Examination reveals an elevated ESR and CRP. What is the most sensitive and specific imaging modality for the suspected diagnosis?

Explanation

The clinical presentation strongly suggests a spinal epidural abscess. MRI with gadolinium contrast is the gold standard imaging modality, providing excellent detail of the spinal cord, epidural space, and any loculated fluid collections.

Question 52

A 75-year-old man sustains a Type II odontoid fracture following a fall. Which of the following factors most significantly increases his risk of fracture nonunion if managed conservatively?

Explanation

Risk factors for nonunion in Type II odontoid fractures include patient age greater than 50 years, displacement greater than 5 mm, and posterior displacement. Due to poor vascularity at the fracture base, elderly patients have nonunion rates exceeding 30% with conservative care.

Question 53

A 16-year-old boy presents with painful scoliosis and night pain in his mid-back that is completely relieved by ibuprofen. Radiographs show a mild structural curve but no obvious destructive lesions. What is the most likely location of the suspected pathology?

Explanation

The clinical presentation is classic for an osteoid osteoma, which frequently causes a painful, rigid scoliosis. These benign, prostaglandin-secreting bone tumors have a strong predilection for the posterior elements (pedicles, lamina, facets) of the spine.

Question 54

A 29-year-old man is stabbed in the back at the T8 level. Neurological examination reveals loss of motor function and proprioception in his right leg, and loss of pain and temperature sensation in his left leg. What spinal cord syndrome does this represent?

Explanation

Brown-Séquard syndrome results from hemisection of the spinal cord, often due to penetrating trauma. It manifests as ipsilateral loss of motor function (corticospinal tract) and proprioception (dorsal columns), with contralateral loss of pain and temperature (spinothalamic tract).

Question 55

A 65-year-old man presents with bilateral leg pain and cramping that worsens with walking and prolonged standing. The pain is relieved by sitting or leaning forward over a shopping cart. Physical examination is unremarkable at rest. Which of the following is the most likely diagnosis?

Explanation

The patient's symptoms are classic for neurogenic claudication caused by lumbar spinal stenosis. The pain is typically relieved by lumbar flexion, which increases the cross-sectional area of the spinal canal.

Question 56

A 45-year-old man presents with acute onset of right-sided sciatica and weakness in his right foot. Examination reveals 3/5 strength in the extensor hallucis longus and decreased sensation over the dorsal aspect of the right foot. Which intervertebral disc level is most likely herniated?

Explanation

The L5 nerve root is compressed by a paracentral disc herniation at the L4-L5 level. This results in weakness of the extensor hallucis longus and sensory loss over the dorsum of the foot.

Question 57

A 72-year-old woman with pre-existing cervical spondylosis falls forward and strikes her chin on a table, causing sudden hyperextension of her neck. She presents with bilateral upper extremity weakness, greater in the hands than the shoulders, and relatively preserved lower extremity function. What is the most likely diagnosis?

Explanation

Central cord syndrome classically occurs in elderly patients with cervical spondylosis following a hyperextension injury. It affects the medially located cervical motor tracts more than the laterally located lumbar and sacral tracts.

Question 58

A 30-year-old immigrant presents with back pain, low-grade fever, and night sweats for 3 months. Imaging shows destruction of the anterior vertebral bodies of T10 and T11 with a paravertebral mass.

What is the primary route of dissemination for this pathogen to the spine?

Explanation

Spinal tuberculosis (Pott's disease) most commonly spreads to the spine hematogenously. The venous plexus of Batson allows retrograde flow of infected blood to the vertebral bodies.

Question 59

A 50-year-old man with a long history of ankylosing spondylitis presents to the emergency department after a minor fall. He complains of severe lower cervical neck pain but has no neurological deficits. Initial plain radiographs of the cervical spine are read as normal. What is the most appropriate next step in management?

Explanation

Patients with ankylosing spondylitis have highly rigid, osteopenic spines that are extremely susceptible to fractures even from trivial trauma. A CT scan or MRI is mandatory as occult fractures are common and can lead to devastating neurological compromise.

Question 60

An 18-year-old gymnast complains of chronic lower back pain that is exacerbated by spinal extension. Oblique lumbar radiographs demonstrate a "Scotty dog with a collar" sign. At which vertebral level does this pathology most commonly occur?

Explanation

The patient has an isthmic spondylolysis (pars interarticularis defect), which is most commonly seen at the L5 vertebral level. It typically presents with mechanical low back pain exacerbated by extension activities.

Question 61

A 68-year-old woman presents with severe low back pain and neurogenic claudication. Plain radiographs reveal a grade 1 spondylolisthesis at L4-L5. Which of the following best describes the pathogenesis of this specific condition?

Explanation

Degenerative spondylolisthesis most commonly occurs at L4-L5 due to facet joint incompetence and degenerative changes. Unlike isthmic spondylolisthesis, the pars interarticularis remains intact.

Question 62

A 25-year-old man is involved in a high-speed motor vehicle collision while wearing only a lap belt. Radiographs show a transverse fracture through the vertebral body, pedicles, and spinous process of L1. What associated injury must be actively ruled out?

Explanation

Chance fractures are flexion-distraction injuries highly associated with lap seatbelts. They have a high incidence (up to 50%) of associated intra-abdominal injuries, particularly hollow viscus rupture.

Question 63

A patient sustains a penetrating knife wound to the right side of his thoracic spine. Neurological examination reveals loss of motor function and proprioception in his right leg, and loss of pain and temperature sensation in his left leg. What is the name of this spinal cord syndrome?

Explanation

Brown-Sequard syndrome results from spinal cord hemisection. It is characterized by ipsilateral loss of motor function and dorsal column function, and contralateral loss of spinothalamic function.

Question 64

A 45-year-old woman presents with neck pain radiating down her arm. She has weakness with wrist extension and a diminished brachioradialis reflex. She reports numbness over her thumb and index finger. Which cervical nerve root is most likely affected?

Explanation

The C6 nerve root provides motor innervation to the wrist extensors and sensory innervation to the thumb and index finger. It serves as the efferent limb of the brachioradialis reflex.

Question 65

A 70-year-old man is evaluated for progressive dysphagia and mild neck stiffness. Lateral cervical spine radiographs show flowing ossification along the anterolateral aspect of four contiguous vertebral bodies with preserved disc heights.

What is the most likely diagnosis?

Explanation

DISH is characterized by flowing anterior ossification across at least four contiguous vertebral bodies with preserved intervertebral disc spaces. In the cervical spine, large anterior osteophytes can cause mechanical dysphagia.

Question 66

A 60-year-old man with diabetes presents with severe, progressive back pain, a low-grade fever, and bilateral lower extremity weakness that began 24 hours ago. His ESR and CRP are markedly elevated. Which of the following is the most appropriate definitive treatment?

Explanation

The patient's presentation is highly suspicious for a spinal epidural abscess with developing neurological deficits. Emergent surgical decompression combined with targeted antibiotics is the standard of care to prevent irreversible paraplegia.

Question 67

A 75-year-old man sustains a Type II odontoid fracture after a fall. Which of the following factors is most predictive of nonunion if treated conservatively with a halo vest?

Explanation

Risk factors for nonunion of a Type II odontoid fracture include age greater than 50 years, fracture displacement greater than 5 mm, and posterior displacement. Due to poor outcomes with halo immobilization in the elderly, surgical fixation is often preferred.

Question 68

When placing a pedicle screw in the lumbar spine, which anatomical landmarks are primarily used to identify the optimal starting point?

Explanation

The standard starting point for a lumbar pedicle screw is located at the intersection of a vertical line tangential to the lateral border of the superior articular facet and a horizontal line bisecting the transverse process.

Question 69

Among the incomplete spinal cord injury syndromes, which one classically carries the worst prognosis for functional motor recovery?

Explanation

Anterior cord syndrome results from injury to the anterior two-thirds of the spinal cord, leading to loss of motor function and pain/temperature sensation. It has the poorest prognosis for functional recovery, with fewer than 20% of patients regaining significant motor function.

Orthopedic Prometric MCQs - Chapter 3 Part 1

Orthopedic Prometric MCQs - Chapter 3 Part 23

Orthopedic Prometric MCQs - Chapter 3 Part 23

Chapter Index