Back Practice Questions

Q: Regarding the epidural space, all are true except:

Continues through foramen magnum into the skull. ***Continues through foramen magnum into the skull*** - The spinal **epidural space** is bounded superiorly by the **foramen magnum**, where the dural layer fuses with the periosteum of the cranium. - In the skull, the dura is tightly adherent to the bone, meaning there is no **natural epidural space** like the one found in the vertebral column. *Ends at the sacrococcygeal membrane* - The inferior boundary of the epidural space is the **sacrococcygeal membrane**, which seals the **sacral hiatus**. - This anatomical limit is crucial for the safe administration of **caudal anesthesia**. *Is an open space* - The epidural space is an **open potential space** containing **adipose tissue** and the **internal vertebral venous plexus**. - It is not a closed compartment, allowing for the **circumferential spread** of local anesthetics during medical procedures. *Lies outside of the dura mater* - By definition, the **epidural space** is located between the **outer layer of the dura mater** and the walls of the vertebral canal. - It serves as a protective cushion of **fat and connective tissue** surrounding the spinal meninges.

Q: Which of the following structures provides the main nutritional supply to the intervertebral disc?

Vertebral endplates. ***Vertebral endplates*** - The **vertebral endplates** are thin layers of cartilage and bone that cover the superior and inferior surfaces of the vertebral bodies. - They are crucial for nutrient diffusion from the vertebral body capillaries into the avascular intervertebral disc. *Anterior longitudinal ligament* - The **anterior longitudinal ligament** is a strong, fibrous band that runs along the anterior surfaces of the vertebral bodies and intervertebral discs. - Its primary role is to prevent hyperextension of the spine and it does not directly supply nutrients to the disc. *Posterior longitudinal ligament* - The **posterior longitudinal ligament** is located on the posterior aspect of the vertebral bodies, inside the vertebral canal. - Its main function is to restrict hyperflexion and posterior disc herniation, without providing significant nutritional support. *Ligamentum flavum* - The **ligamentum flavum** connects the laminae of adjacent vertebrae, primarily composed of elastic tissue. - It helps maintain the upright posture and provides flexibility to the vertebral column but is not involved in disc nutrition.

Q: While performing a lumbar puncture, a snap is felt just before entering into the epidural space. This is due to piercing of which structure?

Ligamentum flavum. ***Ligamentum flavum*** - The sensation of a "snap" or "pop" during a lumbar puncture just before the epidural space is characteristically felt when the needle penetrates the tough and elastic **ligamentum flavum**. - This ligament connects the laminae of adjacent vertebrae and is the most significant resistance felt by the needle before reaching the epidural space. *Duramater* - The **dura mater** is the outermost meningeal layer, which is pierced after passing through the epidural space. - Penetrating the dura mater provides a second, typically less pronounced, "pop" or "give" sensation as the needle enters the subarachnoid space to access cerebrospinal fluid. *Posterior longitudinal ligament* - The **posterior longitudinal ligament** is located on the posterior surface of the vertebral bodies, within the spinal canal. - It is not typically pierced during a standard posterior approach lumbar puncture and is not associated with the characteristic "snap." *Supraspinous ligament* - The **supraspinous ligament** is the most superficial ligament in the midline posterior to the vertebral column, connecting the tips of the spinous processes. - While it offers initial resistance, the "snap" associated with entering the epidural space comes from the deeper **ligamentum flavum**, not the supraspinous ligament.

Q: All of the following are superficial muscles of the back, EXCEPT:

Erector spinae. ***Correct: Erector spinae*** - The **erector spinae** muscles (iliocostalis, longissimus, spinalis) are part of the **intermediate layer** of back muscles, lying deep to the superficial extrinsic muscles. - They primarily function in **postural support** and **extension of the vertebral column**. - This is the correct answer because erector spinae is NOT a superficial muscle. *Incorrect: Levator scapulae* - The **levator scapulae** is a **superficial extrinsic back muscle** that elevates the scapula. - It connects the cervical vertebrae to the superior angle of the scapula. *Incorrect: Trapezius* - The **trapezius** is a large, **superficial extrinsic back muscle** involved in moving the scapula and supporting the arm. - It covers a significant portion of the upper back and neck. *Incorrect: Latissimus dorsi* - The **latissimus dorsi** is another large, **superficial extrinsic back muscle** responsible for extending, adducting, and internally rotating the arm. - It is located in the lower and middle back.

Q: Where is the epidural venous plexus located?

In vertebral canal above dura mater. ***In vertebral canal above dura mater*** - The **epidural venous plexus** (also known as **Batson's plexus**) is located in the **epidural space**, which is external to the dura mater. - In the spinal canal, this space is found between the **vertebral canal** (specifically, the periosteum lining the canal) and the **dura mater**. *At the junction of middle and posterior cranial fossa* - This location relates more to specific cranial nerves or arterial structures at the skull base and is not where the epidural venous plexus of the spine is primarily found. - The epidural space in the cranium is a potential space, and the venous plexuses associated with it are typically referred to as **dural venous sinuses**. *Basal ganglia adjacent to pons* - The **basal ganglia** are deep brain structures involved in motor control, and the pons is part of the brainstem, both located within the cranium. - This location is entirely within the brain parenchyma and not in the epidural space of the vertebral canal. *In vertebral canal below dura mater* - Below the dura mater is the **subdural space** (a potential space) and then the **subarachnoid space**, which contains cerebrospinal fluid and is where the spinal cord and nerve roots are located. - The epidural venous plexus is explicitly located *above* (external to) the dura mater, not below it.

Q: Number of vertebrae in human vertebral column is

33. ***Correct Option B: 33*** - The human vertebral column consists of **33 individual vertebrae** in total during early development. - These include **7 cervical**, **12 thoracic**, **5 lumbar**, **5 sacral** (which fuse to form the sacrum), and **4 coccygeal** (which fuse to form the coccyx) vertebrae. *Incorrect Option A: 30* - This number is incorrect; it does not account for all the vertebrae present either individually or in their fused state within the vertebral column. - The total number of vertebrae is higher when counting both individual and fused segments. *Incorrect Option C: 32* - This number is incorrect and falls short of the actual count of vertebrae in the human vertebral column. - It does not correctly represent the full complement of cervical, thoracic, lumbar, sacral, and coccygeal segments. *Incorrect Option D: 31* - This number is incorrect; it does not accurately reflect the total number of vertebrae, including both the individual and completely fused components of the sacrum and coccyx. - It is often confused with the number of 31 pairs of spinal nerves (which is a different count).

Q: Where does the main part of vertebral venous plexus lie?

Epidural space. ***Epidural space*** - The **internal vertebral venous plexus** is located within the **epidural space**, surrounding the dura mater of the spinal cord. - This plexus is a valveless network of veins, which allows for bidirectional blood flow and provides an important pathway for the **spread of infection** and **metastasis**. *Subdural space* - The subdural space is a potential space between the **dura mater** and **arachnoid mater**, typically not containing significant venous plexuses. - While it can fill with blood in cases of **subdural hematoma**, it is not the primary location of the vertebral venous plexus. *External to the vertebral column* - The **external vertebral venous plexuses** are located outside the vertebral column, both anterior and posterior to the vertebrae. - Although these plexuses exist, the "main part" often refers to the internal plexus within the spinal canal due to its clinical significance and close association with the **spinal cord**. *Subarachnoid space* - The subarachnoid space lies between the **arachnoid mater** and **pia mater** and contains **cerebrospinal fluid (CSF)** and major arteries. - While small veins might traverse this space, it does not house the expansive network of the vertebral venous plexus.

Q: Epidural space lies between:

Dura and vertebral column. ***Dura and vertebral column*** - The **epidural space** is located between the dura mater and the surrounding vertebral column (specifically the **periosteum** lining the vertebral canal). - This space contains **fat, connective tissue**, and a **venous plexus**, acting as a protective cushion for the spinal cord. *Dura and arachnoid* - The space between the dura mater and the arachnoid mater is the **subdural space** [1]. - This is normally a **potential space** but can become a real space in pathological conditions like a subdural hematoma [1]. *Pia and arachnoid* - The space between the pia mater and the arachnoid mater is the **subarachnoid space** [1]. - This space normally contains **cerebrospinal fluid (CSF)** and blood vessels [1]. *Pia mater and grey matter* - The pia mater is directly apposed to the surface of the brain and spinal cord, including its **grey matter**. - There is no distinct "space" between the pia mater and the neural tissue it covers.

Q: Which vertebra is known as vertebra prominens due to its long and prominent spinous process:

C7. ***C7*** - The **seventh cervical vertebra (C7)** is often referred to as the **vertebra prominens** because its spinous process is distinctly longer and more prominent than those of the other cervical vertebrae. - This prominence makes it easily **palpable** at the base of the neck, serving as a key anatomical landmark. *C2* - The spinous process of **C2 (axis)** is bifid and significantly shorter than that of C7. - While important for head rotation, its length does not compare to the palpable prominence of C7. *T2* - **Thoracic vertebrae** generally have long spinous processes that project inferiorly, but **T2's spinous process** is not the longest overall. - The processes get progressively longer moving down the thoracic spine until about T7. *L3* - **Lumbar vertebral spinous processes** are broad, thick, and relatively blunt, projecting horizontally. - While robust, the spinous process of **L3** is not as long or prominent as that of C7.

Question 1

Regarding the epidural space, all are true except:

Accepted Answer

Continues through foramen magnum into the skull

Answer

Ends at the sacrococcygeal membrane

Answer

Is an open space

Answer

Lies outside of the dura mater

Question 2

Which of the following structures provides the main nutritional supply to the intervertebral disc?

Accepted Answer

Vertebral endplates

Answer

Anterior longitudinal ligament

Answer

Posterior longitudinal ligament

Answer

Ligamentum flavum

Question 3

What constitutes a spinal motion segment?

Accepted Answer

A disc and the vertebrae above and below, including their interlocking facet joints.

Answer

A disc and the facet joints at that level.

Answer

A vertebral body and the disc above.

Answer

A section of the spine involved in a physiological curve with the similar function (i.e. thoracic kyphosis).

Question 4

While performing a lumbar puncture, a snap is felt just before entering into the epidural space. This is due to piercing of which structure?

Accepted Answer

Ligamentum flavum

Answer

Dura mater

Answer

Posterior longitudinal ligament

Answer

Supraspinous ligament

Question 5

All of the following are superficial muscles of the back, EXCEPT:

Accepted Answer

Erector spinae

Answer

Levator scapulae

Answer

Trapezius

Answer

Latissimus dorsi

Question 6

Where is the epidural venous plexus located?

Accepted Answer

In vertebral canal above dura mater

Answer

At the junction of middle and posterior cranial fossa

Answer

Basal ganglia adjacent to pons

Answer

In vertebral canal below dura mater

Question 7

Number of vertebrae in human vertebral column is

Accepted Answer

33

Answer

30

Answer

32

Answer

31

Question 8

Where does the main part of vertebral venous plexus lie?

Accepted Answer

Epidural space

Answer

Subdural space

Answer

External to the vertebral column

Answer

Subarachnoid space

Question 9

Epidural space lies between:

Accepted Answer

Dura and vertebral column

Answer

Dura and arachnoid

Answer

Pia and arachnoid

Answer

Pia mater and grey matter

Question 10

Which vertebra is known as vertebra prominens due to its long and prominent spinous process:

Accepted Answer

C7

Answer

C2

Answer

T2

Answer

L3

Back — MCQs

Back — MCQs

On this page

Practice by Chapter

Want unlimited practice?