Question 1

If the C 5 cervical spine nerve root is injured during a decompression of the cervical spine, then sensation is lost over which of the following areas:

Explanation

The C 5 cervical spine nerve root supplies sensation from the lateral aspect of the arm from the shoulder to the elbow. C5 Lateral aspect of the arm from the shoulder to the elbow C6 Lateral border of the forearm including the thumb C7 Middle finger C8 Medial border of the forearm including the little finger T1 Medial aspect of the arm from the shoulder to the elbow

Question 2

If the C 6 cervical spine nerve root is injured during a posterior decompression of the cervical spine, then sensation is lost in which of the following areas:

Explanation

If the C 6 cervical spine nerve root is injured during a posterior decompression of the cervical spine, then sensation is lost in which of the following areas: C 5 Lateral aspect of the arm from the shoulder to the elbow C 6 Lateral border of the forearm including the thumb C 7 Middle finger C 8 Medial border of the forearm including the little finger T1 Medial aspect of the arm from the shoulder to the elbow

Question 3

If the C 7 cervical spine nerve root is injured during a posterior decompression of the cervical spine, then sensation is lost in which of the following areas:

Explanation

The C7 cervical spine nerve root supplies sensation to the skin over the volar aspect of the middle finger. C 5 Lateral aspect of the arm from the shoulder to the elbow C 6 Lateral border of the forearm including the thumb C 7 Middle finger C 8 Medial border of the forearm including the little finger T1 Medial aspect of the arm from the shoulder to the elbow

Question 4

If the C 8 cervical spine nerve root is injured during a posterior spinal decompression, then sensation is lost over which of the following areas:

Explanation

The C8 cervical spine nerve root supplies sensation to the medial border of the forearm including the little finger. C5 Lateral aspect of the arm from the shoulder to the elbow C 6 Lateral border of the forearm including the thumb C7 Middle finger C8 Medial border of the forearm including the little finger T1 Medial aspect of the arm from the shoulder to the elbow

Question 5

If the brachioradialis reflex is diminished after a posterior spinal decompression, then which of the following nerve roots is injured:

Explanation

The brachioradialis reflex is mediated by the C 6 cervical spine nerve root. C 5 Biceps C 6 Brachioradialis C 7 Triceps

Question 6

If the triceps muscle is weak after a spinal decompression, then which of the following nerve roots is injured:

Explanation

The triceps muscle extends the elbow and is innervated by the C 7 cervical spine nerve root. Motor innervations include: Shoulder abduction (deltoid) - - C 5 Elbow flexion - - C 5 Wrist extension - - C 6, C 7 Wrist flexion - - C 7 Finger extension - - C 7 Finger flexion - - C 8 Finger abduction/adduction - - T1

Question 7

If the flexor carpi radialis is weak after a spinal decompression, then which of the following nerve roots is injured:

Explanation

The flexor carpi radialis is the most powerful wrist flexor and is innervated by the C 7 cervical spine nerve root. The flexor carpi ulnaris, which is weaker than the flexor carpi radialis, is innervated by the C 8 cervical spine nerve root.

Question 8

A patient has a fracture dislocation of the cervical spine. Which of the following nerve roots must be spared to preserve intact finger extension:

Explanation

Finger extensors are innervated by the C 7 cervical spine nerve root. Motor innervations include: Shoulder abduction (deltoid) - - C 5 Elbow flexion - - C 5 Wrist extension - - C 6, C 7 Wrist flexion - - C 7 Finger extension - - C 7 Finger flexion - - C 8 Finger abduction/adduction - - T1

Question 9

Which of the following nerve roots supplies motor innervation to the flexor digitorum superficialis (FDS):

Explanation

The FDS flexes the proximal interphalangeal joint and is innervated by the C 8 cervical spine nerve root. The FDS is innervated peripherally by the median nerve. The flexor digitorum profundus flexes the distal interphalangeal joint and is also innervated by the C 8 cervical spine nerve root. The middle and index fingers are supplied by the median nerve, and the ring and little fingers are supplied by the ulnar nerve.

Question 10

A patient with a herniated disk has a diminished patellar tendon reflex. Which of the following lumbosacral nerve roots is affected:

Explanation

The patellar tendon reflex is primarily transmitted through the L4 lumbosacral nerve root. Although the L4 lumbosacral nerve root is the primary transmitter, the L2 and L3 lumbosacral nerve roots also contribute to the fibers. A weak reflex is present if the L4 lumbosacral nerve root is completely cut and fibers of the L2 and L3 lumbosacral nerve roots are still present. The patellar tendon reflex is seldom completely absent unless a patient has primary muscle or anterior horn lesions.

Question 11

A patient with radicular pain is experiencing skin numbness on the medial aspect of his leg and great toe. Which of the following nerve roots is effected:

Explanation

When examining patients, it is important to remember the sensory dermatomes. The medial aspect of the leg, foot, and great toe are supplied by the L4 lumbosacral nerve root. The tibial crest separates the L4 and L5 dermatomes on the leg. L4 Medial aspect of leg, foot, and great toe L5 Lateral aspect of the leg and toes 2 through 4 S1 Lateral aspect of the fifth toe

Question 12

If the extensor hallucis longus muscle is weak in a patient who has radicular pain, then which of the following lumbosacral nerve roots is compressed:

Explanation

The extensor hallucis longus muscle is primarily innervated by the L5 lumbosacral nerve root. The L5 lumbosacral nerve root innervates the following muscles: Extensor hallucis longus Extensor digitorum longus and extensor digitorum brevis Gluteus medius

Question 13

If the extensor digitorum longus and extensor digitorum brevis muscles are weak in a patient who has radicular back pain, then which of the following lumbosacral nerve roots is compressed:

Explanation

The extensor hallucis longus muscle is primarily innervated by the L5 lumbosacral nerve root. The L5 lumbosacral nerve root innervates the following muscles: Extensor hallucis longus Extensor digitorum longus and extensor digitorum brevis Gluteus medius

Question 14

Testing of the L5 lumbosacral nerve root in a patient who has radicular back pain can be accomplished through which of the following reflexes or tests:

Explanation

Although there is not a well-defined reflex arc for the L5 lumbosacral nerve root, the tibialis posterior reflex can be elicited. The tibialis posterior reflex is mediated through the L5 lumbosacral nerve root. Reflexes and associated nerve roots include: Patellar tendon --- L4 Achilles tendon --- S1 Superficial anal reflex --- S2, S3, S4 Beevor sign refers to asymmetry of the segmental innervation of the rectus abdominus muscles and when performing a situp, there is unilateral segmental nerve root loss.

Question 15

A patient with radicular pain is experiencing skin numbness on the lateral aspect of the leg and the dorsum of the foot between the second and fourth toes. Which of the following nerve roots is being compressed:

Explanation

The L5 dermatome covers the skin on the lateral leg and dorsum of the foot from the lateral border of the great toe to the medial border of the little toe. L4 Medial aspect of leg, foot, and great toe L5 Lateral aspect of the leg and toes 2 through 4 S1 Lateral aspect of the fifth toe

Question 16

If the peroneus longus and peroneus brevis muscles are weak in a patient who has radicular back pain, then which of the following nerve roots is compressed:

Explanation

The peroneus brevis and peroneus longus muscles are principally innervated by the S1 nerve root through the superficial peroneal nerve. Although the nerve is principally innervated by the S1 nerve root, the superficial peroneal nerve is derived from the L5, S1, and S2 nerve roots. The muscles principally innervated by the S1 nerve root are the: Peroneus longus and peroneus brevis Gastrocnemius-soleus complex Gluteus maximus

Question 17

The left medial and lateral gastrocnemius muscles are weak in a patient after a lumbar spine decompression. Which of the following nerve roots is injured:

Explanation

The medial and lateral gastrocnemius muscles are principally innervated by the S1 nerve root through the tibial nerve. Although the nerve is principally innervated by the S1 nerve root, the tibial nerve is derived from the L5, S1, and S2 nerve roots. The muscles principally innervated by the S1 nerve root are the: Peroneus longus and peroneus brevis Gastrocnemius-soleus complex Gluteus maximus

Question 18

The Achilles tendon reflex (ankle reflex) is absent in a patient who has radicular back pain. Which of the following nerve roots is compressed:

Explanation

The Achilles tendon reflex is based on the triceps muscle group (medial and lateral gastrocnemius muscles and soleus muscle) and is transmitted through the S1 nerve root. Reflexes and associated nerve roots include: Patellar tendon reflex L4 Posterior tibial reflex L5 Achilles tendon reflex S1

Question 19

A patient with cauda equina syndrome has decreased perianal sensation. Which of the following groups of nerve roots is involved:

Explanation

Perianal sensation is derived from the S2, S3, S4, and S5 nerve roots. The sensory distribution is as follows: S4-S5 - - Innermost perianal ring S3 - - Middle perianal ring S2 - - Outermost perianal ring

Question 20

A patient with a fracture dislocation of the spine has a sensory level at the nipple line. Which of the following nerve root levels indicates this finding:

Explanation

In addition to knowing the innervation of selected muscles and the deep tendon reflexes, the clinician should also know the sensory levels to localize pathologic processes. T4 Nipple line T7 Xiphoid process T10 Umbilicus T12 Groin

Question 21

During a posterior cervical foraminotomy at C7-T1, the C8 nerve root is inadvertently injured. Sensation is most likely lost over which of the following areas?

Explanation

The C8 nerve root supplies sensation to the ulnar side of the hand, ring, and small fingers, as well as the ulnar aspect of the distal forearm.

Question 22

A patient presents with isolated weakness of the deltoid and biceps after a high-energy motor vehicle accident. Which cervical nerve root is most likely compromised?

Explanation

The C5 nerve root primarily innervates the deltoid (via the axillary nerve) and biceps (via the musculocutaneous nerve). Deficits result in profound weakness in shoulder abduction and elbow flexion.

Question 23

An elderly patient with pre-existing cervical stenosis experiences a hyperextension injury to the neck. Examination reveals profound weakness in the upper extremities with relatively preserved lower extremity strength. What is the most likely diagnosis?

Explanation

Central cord syndrome typically occurs after a hyperextension injury in a stenotic cervical spine. It causes greater motor impairment in the upper extremities than the lower extremities due to the central location of the upper extremity corticospinal tracts.

Question 24

A 45-year-old man presents with severe neck pain radiating to his left arm. Physical examination reveals weakness in elbow extension and wrist flexion, along with an absent triceps reflex. Which nerve root is most likely affected?

Explanation

The C7 nerve root provides motor innervation for elbow extension (triceps) and wrist flexion (flexor carpi radialis). It also mediates the triceps reflex.

Question 25

Following a burst fracture of C5, a patient has bilateral loss of motor function and pain/temperature sensation below the level of injury, but intact proprioception and vibratory sense. Which spinal cord syndrome is present?

Explanation

Anterior cord syndrome results from injury to the anterior two-thirds of the spinal cord, causing loss of motor, pain, and temperature sensation. The dorsal columns are spared, preserving proprioception and vibration.

Question 26

During evaluation of a 65-year-old male with clumsy hands and gait imbalance, flicking the nail of the middle finger results in flexion of the thumb and index finger. What is this clinical sign called?

Explanation

Hoffmann's sign is an indicator of an upper motor neuron lesion and is a classic finding in cervical myelopathy. It is elicited by flicking the distal phalanx of the middle finger, causing reflex flexion of the thumb and index finger.

Question 27

A patient complains of right-sided neck pain radiating to the shoulder. Extension, lateral bending, and axial compression of the neck reproduce the radiating arm pain. Which of the following is the most appropriate term for this test?

Explanation

Spurling's maneuver narrows the neural foramen and exacerbates symptoms of cervical radiculopathy. A positive test is the reproduction of radicular arm pain.

Question 28

A patient sustains a stab wound to the right side of the neck at the C6 level. Which of the following neurological patterns is expected?

Explanation

Brown-Sequard syndrome (hemisection of the cord) causes ipsilateral loss of motor function and proprioception (corticospinal and dorsal columns) and contralateral loss of pain and temperature sensation (spinothalamic tract).

Question 29

A 70-year-old patient falls and sustains a fracture through the base of the odontoid process. Why does this specific fracture type have a high rate of nonunion?

Explanation

Type II odontoid fractures occur at the junction of the dens and the body of C2. They have a high nonunion rate due to the tenuous blood supply at this watershed area and the relatively small fracture surface area.

Question 30

Traumatic spondylolisthesis of the axis (Hangman's fracture) typically involves bilateral fractures of the pars interarticularis of C2. What is the classic mechanism of injury?

Explanation

A Hangman's fracture is typically caused by hyperextension and axial loading, such as in motor vehicle accidents where the chin strikes the dashboard. This results in bilateral pars interarticularis fractures of C2.

Question 31

A 25-year-old male dove into a shallow pool and sustained a burst fracture of the C1 ring. Which radiographic finding on the open-mouth odontoid view is most critical for determining the integrity of the transverse atlantal ligament?

Explanation

In a Jefferson fracture, a combined lateral mass overhang (displacement) of greater than 6.9 mm on the AP open-mouth view strongly suggests a rupture of the transverse atlantal ligament. This indicates significant atlantoaxial instability.

Question 32

A patient undergoes anterior cervical discectomy and fusion at C5-C6. Postoperatively, a new C6 nerve root palsy is noted. Which motor deficit is most likely expected?

Explanation

The C6 nerve root innervates the extensor carpi radialis longus and brevis, primarily controlling wrist extension. It also contributes heavily to elbow flexion.

Question 33

A 60-year-old male with long-standing ankylosing spondylitis sustains a minor fall. He complains of severe neck pain but has no immediate neurological deficits. What is the most critical management step?

Explanation

Patients with ankylosing spondylitis are at extremely high risk for unstable, rigid-spine fractures even from minor trauma. An immediate CT scan is mandatory because plain radiographs often miss these fractures due to altered anatomy and osteopenia.

Question 34

A Pancoast tumor in the lung apex invades the lower brachial plexus, directly compressing the T1 nerve root. Which of the following motor deficits is most characteristic?

Explanation

The T1 nerve root heavily innervates the intrinsic muscles of the hand (dorsal and palmar interossei) via the ulnar nerve. Compression results in profound weakness of finger abduction and adduction.

Question 35

A 55-year-old Asian male presents with progressive clumsiness of his hands and a spastic gait. Lateral cervical radiographs reveal a dense, radiopaque strip along the posterior aspect of the cervical vertebral bodies. What is the most likely diagnosis?

Explanation

OPLL is common in patients of Asian descent and presents with signs of cervical myelopathy. Radiographs show a classic ossification of the ligament situated just posterior to the vertebral bodies.

Question 36

During a posterior cervical mass screw placement at C1, the surgeon must be cautious of the vertebral artery. Where does the vertebral artery typically lie in relation to the C1 posterior arch?

Explanation

The vertebral artery exits the C1 transverse foramen and courses medially in the vertebral groove (sulcus arteriae vertebralis). This groove is located on the superior surface of the posterior arch of the atlas.

Question 37

A 30-year-old male is involved in a severe motor vehicle crash. Lateral cervical radiograph shows a 50% anterior subluxation of C5 on C6. What is the most likely structural injury?

Explanation

Anterior translation of a cervical vertebral body by 50% or more over the adjacent inferior segment is highly indicative of bilateral facet dislocation. Unilateral facet dislocation typically presents with approximately 25% anterior translation.

Question 38

A patient with multiple sclerosis and a known cervical demyelinating plaque complains of a sudden, electric shock-like sensation running down his spine and into his limbs when he flexes his neck. What is this clinical phenomenon?

Explanation

Lhermitte's sign is an electric shock-like sensation radiating down the spine or limbs upon neck flexion. It indicates dorsal column dysfunction and is commonly seen in multiple sclerosis or cervical spondylotic myelopathy.

Question 39

A 65-year-old woman with severe, long-standing rheumatoid arthritis is scheduled for a total knee arthroplasty. Which preoperative radiographic view of the cervical spine is most critical for the anesthesiologist to review prior to intubation?

Explanation

Patients with rheumatoid arthritis frequently develop atlantoaxial instability due to pannus destruction of the transverse ligament. Flexion-extension lateral radiographs are critical to evaluate for abnormal atlantodental interval (ADI) prior to intubation.

Question 40

A 28-year-old female presents with pain, numbness, and tingling in the ulnar distribution of her hand. Symptoms are exacerbated by overhead activities. Examination shows a positive Roos test but normal cervical MRI. Compression of which structure is most likely responsible?

Explanation

Neurogenic thoracic outlet syndrome most commonly involves compression of the lower trunk of the brachial plexus (C8 and T1 nerve fibers). This leads to symptoms in the ulnar nerve distribution and intrinsic hand muscle weakness.

Question 41

If the C8 cervical spine nerve root is injured during an anterior decompression and fusion, sensation is most likely lost over which of the following areas?

Explanation

The C8 dermatome provides sensation to the ulnar side of the hand and the little finger. In contrast, C6 supplies the lateral forearm and thumb, C7 the middle finger, and T1 the medial forearm.

Question 42

If the T1 spinal nerve root is injured during surgery at the cervicothoracic junction, the patient will present with sensory loss in which primary distribution?

Explanation

The T1 dermatome covers the medial aspect of the forearm. The C8 nerve root supplies the medial hand, while the T2 dermatome supplies the medial upper arm and axilla.

Question 43

During an anterior cervical discectomy and fusion (ACDF) at C5-C6, the patient develops postoperative hoarseness. Which nerve was most likely injured and where does it reside?

Explanation

The recurrent laryngeal nerve courses in the tracheoesophageal groove and is vulnerable during lower cervical anterior exposures. Injury results in unilateral vocal cord paralysis, which presents clinically as hoarseness.

Question 44

An ACDF is performed at the C3-C4 level. Postoperatively, the patient has a normal speaking voice but complains of easy vocal fatigue and an inability to reach high-pitched notes. Which nerve was likely injured?

Explanation

The external branch of the superior laryngeal nerve innervates the cricothyroid muscle. Injury impairs vocal cord tension, leading to easy vocal fatigue and loss of high-pitched phonation, typically seen in upper cervical exposures.

Question 45

Which of the following is the most common neurologic complication following a posterior cervical laminectomy and fusion for multilevel cervical spondylotic myelopathy?

Explanation

C5 palsy is a well-documented complication following posterior cervical decompression, occurring in up to 10% of cases. It presents as delayed unilateral deltoid and biceps weakness due to posterior shift of the spinal cord and tethering of the C5 root.

Question 46

During an anterior exposure of the lower cervical spine, dissection extends laterally over the longus colli muscle. Postoperatively, the patient presents with ipsilateral ptosis, miosis, and anhidrosis. What structure was injured?

Explanation

Injury to the cervical sympathetic trunk, which runs anterior to the longus colli muscles, causes Horner syndrome. Dissection should remain medial to the lateral border of the longus colli to avoid this complication.

Question 47

A patient presents with a paracentral disc herniation at the L3-L4 level. Which of the following physical examination findings is most likely to be present?

Explanation

A paracentral disc herniation at L3-L4 typically compresses the traversing L4 nerve root. This results in weakness of ankle dorsiflexion, sensory loss over the medial lower leg, and a diminished or absent patellar reflex.

Question 48

A patient presents with a far lateral (extraforaminal) disc herniation at the L4-L5 level. Which nerve root is primarily affected by this specific herniation?

Explanation

A far lateral disc herniation compresses the exiting nerve root at the same level. Therefore, an L4-L5 far lateral disc herniation compresses the L4 nerve root, whereas a paracentral herniation would compress the traversing L5 root.

Question 49

Compression of the L5 nerve root in the lumbar spine typically results in sensory loss in which of the following specific areas?

Explanation

The L5 dermatome classically supplies the dorsum of the foot, specifically isolated at the first dorsal web space. It also provides motor innervation to the extensor hallucis longus and gluteus medius.

Question 50

A patient has an absent ankle jerk reflex, weakness in plantar flexion, and sensory loss over the lateral border of the foot. Which nerve root is most likely compressed?

Explanation

The S1 nerve root innervates the gastrocnemius-soleus complex and mediates the Achilles reflex. Its sensory dermatome covers the lateral border and the plantar surface of the foot.

Question 51

Which of the following clinical findings serves as the primary indicator that the phase of spinal shock has ended following a traumatic spinal cord injury?

Explanation

Spinal shock is characterized by areflexia and flaccidity below the level of a spinal cord injury. The return of the bulbocavernosus reflex is the earliest reliable clinical indicator that spinal shock has resolved.

Question 52

A patient with a previous T4 spinal cord injury suddenly develops a pounding headache, profuse sweating above the level of injury, and a blood pressure of 210/110 mmHg. What is the most common triggering event for this condition?

Explanation

Autonomic dysreflexia occurs in patients with spinal cord injuries above T6 and is characterized by massive sympathetic discharge. A distended bladder or bowel impaction is the most common noxious trigger, requiring immediate intervention.

Question 53

A 70-year-old man with underlying cervical spondylosis sustains a hyperextension injury to his neck. He presents with bilateral upper extremity weakness, profound in the hands, but has relatively preserved lower extremity strength. What is the most likely diagnosis?

Explanation

Central cord syndrome typically occurs after hyperextension injuries in elderly patients with pre-existing cervical stenosis. Due to the medial location of the upper extremity cervical tracts, hand and arm motor function is much more severely affected than the legs.

Question 54

A patient suffers an ischemic injury to the anterior spinal artery. Which of the following neurologic functions will remain intact?

Explanation

Anterior cord syndrome spares the dorsal columns, which are supplied independently by the posterior spinal arteries. Therefore, proprioception, vibratory sense, and fine touch remain intact while motor, pain, and temperature functions are lost.

Question 55

A patient sustains a stab wound resulting in a spinal cord hemisection. Below the level of the lesion, what is the expected neurologic deficit pattern?

Explanation

Brown-Sequard syndrome results from a spinal cord hemisection. Patients exhibit ipsilateral loss of motor function and proprioception, combined with a contralateral loss of pain and temperature sensation.

Question 56

During the posterior placement of C1-C2 transarticular screws, an unrecognized injury to the vertebral artery occurs. To minimize the risk of this complication, preoperative imaging must specifically evaluate for which of the following?

Explanation

A high-riding vertebral artery or a narrow C2 pars interarticularis significantly increases the risk of vertebral artery injury during C1-C2 transarticular or C2 pedicle screw placement. Preoperative CT angiography is critical to identify this anomaly.

Question 57

Which of the following is typically the earliest clinical symptom reported by patients developing cervical spondylotic myelopathy?

Explanation

Hand clumsiness and difficulty with fine motor skills (e.g., buttoning shirts, picking up coins) are often the earliest symptoms of cervical spondylotic myelopathy. Gait imbalance and a feeling of heavy legs also frequently follow.

Question 58

A 55-year-old diabetic patient presents with severe back pain, low-grade fever, and progressive bilateral lower extremity weakness over the last 48 hours. An MRI reveals an anterior epidural fluid collection with peripheral enhancement at T8-T9. What is the most appropriate next step in management?

Explanation

The patient has a spinal epidural abscess presenting with progressive neurologic deficits, which constitutes an absolute surgical emergency. Immediate surgical decompression and debridement are required to prevent irreversible paralysis.

Question 59

A patient develops a C8 nerve root palsy following a posterior cervical foraminotomy. Which of the following motor deficits is most likely to be observed on clinical examination?

Explanation

The C8 nerve root supplies the flexor digitorum profundus and superficialis, controlling finger flexion. Finger abduction is primarily innervated by T1, while wrist extension is mediated by C6.

Question 60

During an anterior cervical discectomy and fusion (ACDF) at the C5-C6 level, a right-sided approach is utilized. Postoperatively, the patient complains of persistent hoarseness. Which of the following structures was most likely injured?

Explanation

The recurrent laryngeal nerve is at risk during anterior cervical approaches. A right-sided approach has historically been associated with a slightly higher risk due to the nerve's more variable and oblique course compared to the left.

Question 61

A 65-year-old male with pre-existing cervical stenosis experiences a hyperextension injury. He presents with bilateral upper extremity weakness, notably worse in the hands than the shoulders, and relatively preserved lower extremity strength. What is the most likely diagnosis?

Explanation

Central cord syndrome typically occurs after a hyperextension injury in a stenotic cervical spine. It presents with upper extremity weakness greater than lower extremity weakness, particularly affecting distal hand motor function.

Question 62

In a patient with long-standing rheumatoid arthritis, which of the following radiographic findings represents the most critical indication for occipitocervical fusion rather than an isolated C1-C2 fusion?

Explanation

Cranial settling (basilar invagination or superior migration of the odontoid) indicates vertical instability and typically requires occipitocervical fusion to prevent brainstem compression. An isolated increased ADI without cranial settling may only require a C1-C2 fusion.

Question 63

Following an anterior cervical corpectomy, a patient develops unilateral ptosis, miosis, and anhidrosis. Retractor placement over which of the following muscles most likely caused this complication?

Explanation

Horner's syndrome can occur from injury to the sympathetic chain, which runs longitudinally over the longus colli muscle. Placing self-retaining retractors too far laterally over the longus colli increases the risk of this complication.

Question 64

A 60-year-old male undergoes a C3-C7 posterior cervical laminectomy and fusion for multilevel spondylotic myelopathy. On postoperative day 2, he develops isolated deltoid and biceps weakness. What is the most likely etiology?

Explanation

C5 palsy is a known complication of posterior cervical decompression, occurring in up to 5-10% of cases. It is thought to be caused by tethering of the short C5 nerve root as the spinal cord drifts posteriorly following decompression.

Question 65

An 82-year-old male sustains a Type II odontoid fracture with 3 mm of posterior displacement following a ground-level fall. He has severe medical comorbidities. What is the most appropriate management?

Explanation

In elderly patients with severe medical comorbidities, a rigid cervical collar is often preferred despite a higher nonunion rate, as halo vest immobilization carries a high mortality risk in this population. Surgery is reserved for patients who fail conservative management or can tolerate the procedure.

Question 66

A traumatic spondylolisthesis of the axis (Hangman's fracture) primarily involves bilateral fractures of which of the following anatomic structures?

Explanation

A Hangman's fracture is defined as bilateral fractures through the pars interarticularis of C2 (the axis). It is typically caused by hyperextension and axial loading mechanisms.

Question 67

A 30-year-old male presents with a unilateral facet dislocation at C5-C6 and is neurologically intact. He is alert and cooperative. What is the most accepted next step in management?

Explanation

In an awake, cooperative, and neurologically intact patient with a cervical facet dislocation, closed reduction with cranial traction can be performed safely prior to MRI. Frequent clinical neurologic exams must be performed during the serial weight additions.

Question 68

Which of the following radiographic findings on an open-mouth odontoid view suggests disruption of the transverse atlantal ligament in a patient with a Jefferson burst fracture?

Explanation

Spence's rule states that if the combined overhang of the C1 lateral masses on C2 is 6.9 mm or greater on an open-mouth AP radiograph, it indicates an incompetent transverse atlantal ligament, rendering the fracture highly unstable.

Question 69

A patient sustains a traction injury to the lower brachial plexus resulting in an isolated T1 nerve root deficit. Which of the following physical examination findings will be most prominent?

Explanation

The T1 nerve root primarily innervates the intrinsic muscles of the hand, including the dorsal interossei, which are responsible for finger abduction. The lateral forearm and wrist extension are predominantly C6.

Question 70

A 25-year-old male arrives at the trauma bay completely tetraplegic after a diving accident. His heart rate is 55 bpm, and blood pressure is 85/50 mmHg. The bulbocavernosus reflex is absent. Which of the following states best describes his condition?

Explanation

The absence of the bulbocavernosus reflex indicates spinal shock (loss of all reflex activity below the injury). The triad of hypotension, bradycardia, and peripheral vasodilation simultaneously defines neurogenic shock, caused by a loss of sympathetic tone.

Question 71

A patient suffers a severe flexion injury of the cervical spine resulting in an anterior spinal cord syndrome. Which of the following neurologic functions is typically preserved?

Explanation

Anterior cord syndrome involves injury to the anterior two-thirds of the spinal cord, causing a loss of motor function and pain/temperature sensation. The posterior columns are spared, preserving proprioception and vibratory sense.

Question 72

When planning intubation for a patient with severe rheumatoid arthritis, the anesthesiologist should be particularly cautious of atlantoaxial instability. Which ligament's laxity or destruction is the primary cause of this instability?

Explanation

The transverse ligament is the primary stabilizer of the atlantoaxial joint. Pannus formation in rheumatoid arthritis often leads to the destruction of this ligament, causing anterior atlantoaxial subluxation.

Question 73

Which of the following demographic groups has the highest incidence of Ossification of the Posterior Longitudinal Ligament (OPLL), leading to cervical myelopathy?

Explanation

OPLL is most prevalent in the Asian population, particularly among Japanese men. It is a major cause of cervical myelopathy in this demographic, often requiring surgical decompression via laminoplasty or laminectomy.

Question 74

When placing posterior cervical instrumentation, which of the following screw trajectories carries the highest recognized risk of iatrogenic vertebral artery injury?

Explanation

C2 pedicle and pars screws carry a significant risk of vertebral artery injury due to the artery's medial and superior path through the C2 foramen. Preoperative CT angiography is often used to assess for a 'high-riding' vertebral artery to mitigate this risk.

Question 75

A patient presents with neck pain radiating down the arm. The examiner performs the Spurling test by extending and laterally bending the patient's neck to the affected side while applying axial compression. What does a positive test indicate?

Explanation

The Spurling test actively narrows the neural foramen. Reproduction of radicular arm pain indicates a positive test and is highly specific for cervical nerve root compression (radiculopathy).

Question 76

A 45-year-old female presents with neck pain following a rear-end motor vehicle collision. Radiographs show a loss of the normal cervical lordosis but no fractures or dislocations. Neurologic exam is normal. What is the most appropriate initial management?

Explanation

For a simple whiplash injury (cervical sprain/strain) without neurologic deficits or fractures, early mobilization, NSAIDs, and physical therapy are the standard of care. Prolonged immobilization can delay recovery and is not recommended.

Question 77

A 10-year-old girl is diagnosed with Klippel-Feil syndrome. She has a short neck, low hairline, and limited cervical range of motion. Which of the following organ systems must be evaluated due to high rates of associated congenital anomalies?

Explanation

Klippel-Feil syndrome, characterized by the congenital fusion of cervical vertebrae, is frequently associated with genitourinary anomalies (e.g., unilateral renal agenesis) in over 30% of cases. A screening renal ultrasound is highly recommended.

Question 78

A patient undergoes an anterior cervical discectomy and fusion at C7-T1. Postoperatively, the patient demonstrates a new sensory deficit. If the C8 nerve root is iatrogenically injured, sensation is most likely lost over which of the following areas?

Explanation

The C8 nerve root provides sensory innervation to the medial aspect of the forearm and the ulnar two digits (ring and little fingers). The lateral forearm is C6, medial arm is T1, and the thumb/index finger typically fall under C6 territory.

Question 79

Following a multilevel posterior cervical laminectomy and fusion for cervical spondylotic myelopathy, a patient develops profound weakness in shoulder abduction and elbow flexion on postoperative day 3, without any new sensory deficits. What is the most likely diagnosis?

Explanation

Postoperative C5 palsy is a known complication of cervical decompression, occurring in up to 5-10% of cases. It presents as isolated deltoid and biceps weakness, typically a few days postoperatively, likely due to nerve root tethering or reperfusion injury.

Question 80

During an anterior approach to the lower cervical spine, dissection lateral to the longus colli muscle places a specific nervous structure at risk. Injury to this structure results in which of the following clinical findings?

Explanation

Dissection lateral to the longus colli muscle risks injury to the sympathetic chain and stellate ganglion, leading to Horner's syndrome. This manifests classically as ipsilateral ptosis, miosis, and anhidrosis.

Question 81

An elderly patient with pre-existing cervical stenosis sustains a hyperextension injury. Examination reveals motor weakness that is more pronounced in the hands and upper extremities than in the lower extremities. Which spinal cord tract injury best explains the upper extremity motor deficit?

Explanation

This patient has Central Cord Syndrome. The characteristic upper extremity weakness occurs because the cervical motor fibers are located medially within the lateral corticospinal tract, making them more susceptible to central cord injury.

Question 82

A patient presents with a paracentral herniated nucleus pulposus at the L4-L5 level. Which of the following physical examination findings is most specific to the expected nerve root compression?

Explanation

A paracentral disc herniation at L4-L5 affects the traversing L5 nerve root. L5 radiculopathy characteristically causes weakness in the extensor hallucis longus (great toe extension) and sensory loss over the dorsum of the foot.

Question 83

During insertion of C1-C2 transarticular screws, the surgeon must be keenly aware of the vertebral artery anatomy. At which cervical level does the vertebral artery typically enter the transverse foramen?

Explanation

The vertebral artery typically branches from the subclavian artery and enters the transverse foramen at the C6 level in approximately 90% of individuals. Anomalous entry at C7 or higher occurs less frequently.

Question 84

A 65-year-old male requires surgical decompression for a central T8-T9 calcified disc herniation causing myelopathy. Why is a standard posterior laminectomy strictly contraindicated for this central thoracic disc herniation?

Explanation

A standard posterior laminectomy for a central thoracic disc requires retraction of the thoracic spinal cord to access the disc, which carries an unacceptably high risk of paraplegia. Anterior or posterolateral (costotransversectomy) approaches are required.

Question 85

A patient involved in a motor vehicle collision sustains a penetrating injury to the right side of the cervical spine, resulting in a Brown-Sequard syndrome. Which of the following neurological deficits will be present?

Explanation

Brown-Sequard syndrome involves hemisection of the spinal cord. It presents with ipsilateral loss of motor function and proprioception (corticospinal tract and dorsal columns cross in the medulla) and contralateral loss of pain/temperature (spinothalamic tract crosses near the entry level).

Question 86

In a patient with a traumatic spondylolisthesis of the axis (Hangman's fracture), the primary mechanism of injury is most commonly described as:

Explanation

A Hangman's fracture involves bilateral pars interarticularis fractures of C2. The classic mechanism of injury in modern trauma (like motor vehicle accidents) is sudden hyperextension combined with axial loading.

Question 87

An open-mouth odontoid radiograph of a trauma patient shows a C1 burst fracture (Jefferson fracture). The sum of the lateral mass overhang of C1 on C2 is measured at 8 mm. According to the Rule of Spence, this finding specifically indicates incompetence of which of the following structures?

Explanation

The Rule of Spence dictates that if the total overhang of the C1 lateral masses on C2 exceeds 6.9 mm on an AP radiograph, it implies a rupture of the transverse ligament. This indicates an unstable injury requiring rigid immobilization or surgery.

Question 88

A patient presenting with neurogenic shock following a severe cervical spine injury will classically exhibit which of the following hemodynamic profiles?

Explanation

Neurogenic shock is caused by a loss of sympathetic tone following high spinal cord injury. This results in unopposed vagal tone, classically presenting with hypotension and bradycardia, differentiating it from hypovolemic shock (hypotension/tachycardia).

Question 89

A right-sided anterior cervical approach is utilized for a C6-C7 ACDF. The recurrent laryngeal nerve is at risk. What is the anatomic rationale for the right recurrent laryngeal nerve being more susceptible to injury in the lower neck than the left?

Explanation

The left recurrent laryngeal nerve loops safely under the aortic arch and ascends vertically in the tracheoesophageal groove. The right nerve loops under the right subclavian artery and ascends more obliquely, making it more variable and susceptible to injury during lower cervical approaches.

Question 90

A patient develops severe postoperative dysphagia following a multilevel ACDF. Which of the following intraoperative factors has been most strongly associated with an increased risk of severe prevertebral swelling and chronic dysphagia in this setting?

Explanation

The use of rhBMP-2 in the anterior cervical spine is notorious for causing robust inflammatory responses leading to severe prevertebral soft tissue swelling, dysphagia, and potentially airway compromise. Its use in ACDF is generally considered off-label and requires extreme caution.

Question 91

A patient presents with absent reflexes, profound flaccid paralysis, and absent sensation below the T6 level immediately following a severe MVC. The bulbocavernosus reflex is absent. What is the most likely diagnosis?

Explanation

Spinal shock is a transient physiological state immediately following spinal cord injury, characterized by flaccid paralysis, areflexia, and an absent bulbocavernosus reflex. The definitive completeness of the cord injury cannot be assessed until spinal shock resolves (indicated by the return of the bulbocavernosus reflex).

Question 92

During a microscopic lumbar discectomy at L5-S1 for a far-lateral (extraforaminal) disc herniation, the surgeon must carefully decompress the affected nerve root. Which nerve root is most commonly compressed by a far-lateral disc herniation at the L5-S1 level?

Explanation

While a paracentral disc herniation at L5-S1 affects the traversing S1 root, a far-lateral (extraforaminal) disc herniation at L5-S1 compresses the exiting L5 nerve root.

Question 93

A patient presents with acute cauda equina syndrome secondary to a massive L4-L5 disc herniation. Which of the following preoperative clinical findings is the strongest predictor of poor postoperative recovery of bladder function?

Explanation

The severity of preoperative urinary dysfunction is the most significant predictor of postoperative bladder recovery in cauda equina syndrome. Patients who progress to complete painless urinary retention with overflow incontinence (CES-Retention) have a poorer prognosis than those with incomplete deficits (CES-Incomplete).

Question 94

Ossification of the posterior longitudinal ligament (OPLL) is a frequent cause of myelopathy in certain demographics. OPLL most frequently affects which segment of the spine?

Explanation

OPLL is most commonly found in the cervical spine, particularly in populations of Asian descent. It leads to progressive spinal canal narrowing and cervical myelopathy.

Question 95

The 'K-line' is a critical radiographic parameter used to determine the appropriate surgical approach (anterior vs. posterior) in patients with cervical myelopathy due to OPLL. How is the K-line defined on a neutral lateral cervical radiograph?

Explanation

The K-line is a straight line connecting the midpoints of the spinal canal at C2 and C7. If the OPLL mass crosses anterior to this line (K-line negative), posterior decompression alone is often insufficient, and an anterior approach is generally indicated.

Question 96

A 45-year-old male sustains an anterior spinal artery syndrome following a complex thoracoabdominal aortic aneurysm repair. Which of the following sensory modalities will definitively remain intact below the level of the lesion?

Explanation

Anterior spinal artery syndrome causes bilateral loss of motor function, pain, and temperature sensation. The dorsal columns, which mediate proprioception and vibratory sense, are preserved as they are supplied by the posterior spinal arteries.

Question 97

If the T1 spinal nerve root is injured during an extensive surgical approach to the cervicothoracic junction, motor weakness would be most pronounced in which of the following actions?

Explanation

The T1 nerve root predominantly innervates the intrinsic muscles of the hand via the ulnar and median nerves. Injury to T1 leads to weakness in finger abduction (dorsal interossei) and adduction (palmar interossei).

Orthopedic Prometric MCQs - Chapter 3 Part 1

Orthopedic Prometric MCQs - Chapter 3 Part 27

Orthopedic Prometric MCQs - Chapter 3 Part 27

Chapter Index