Lower Limb Part 1

Question 1

spondylolysis

Answer 1

stress fracture throuhg parts interarticularis of the lumbar vertebrae

Question 2

spondylolithesis

Answer 2

Spondylolisthesis occurs when one vertebra slips forward over the vertebra below it.

Question 3

Intervertebral joints form between intervertebral (IV) disks and the articular surfaces of vertebral bodies. There are no IV disks between ___ and __.

Answer 3

Intervertebral joints form between intervertebral (IV) disks and the articular surfaces of vertebral bodies. There are no IV disks between C1 and C2.

Question 4

The IV discs act as shock absorbers and are composed of an outer fibrous ring, the __ __,
and a gelatinous core, the __ __

Answer 4

The IV discs act as shock absorbers and are composed of an outer fibrous ring, the anulus fibrosus,
and a gelatinous core, the nucleus pulposus

Question 5

Herniation of an intervertebral disc occurs when the __ __ ruptures, breaking through the annulus fibrosus. The rupture usually occurs in a __-__ direction

Answer 5

Herniation of an intervertebral disc occurs when the nucleus pulposus ruptures, breaking through the annulus fibrosus. The rupture usually occurs in a posterior-lateral direction, after which the nucleus pulposis can irritate nearby spinal nerves – resulting in a variety of neurological and muscular symptoms.

Question 6

The most common sites of nerve root compressed are at levels of L__–__ and L__–S__. . L__nerve root is the most common one that could be compressed.

Answer 6

The most common sites of nerve root compressed are at levels of L4–5 and L5–S1. The compressing factors can be at lateral recess and/or foramina; they are at different adjacent lumbar levels for one nerve root. L5 nerve root is the most common one that could be compressed.

Question 7

The most common sites of nerve root compressed are at levels of L4–5 and L5–S1.Posterolateral IV disc herniations are most common because:

Answer 7

Posterolateral IV disc herniations are most common because:
Annulus fibrosus is thinner in this region

Lacking structural support from the anterior longitudinal ligament in this region

Lacking structural support from the posterior longitudinal ligament in this region

Question 8

is there is a disk herniation in the L4/L5 reggion, the __ is affeced. If it’s an L5-S1 herniation, the __ is mostly affected

Answer 8

Question 9

Two ligaments strengthen the vertebral body joints:

Answer 9

: the anterior and posterior longitudinal ligaments, which run the full length of the vertebral column.

Question 10

The posterior longitudinal ligament is weaker and prevents hyperflexion.
• Superior to the foramen magnum, fans out and attaches within cranial cavity as __ __.

Answer 10

The posterior longitudinal ligament is weaker and prevents hyperflexion.
• Superior to the foramen magnum, fans out and attaches within cranial cavity as tectorial membrane.

• Located between the vertebral body and the dura matte

Question 11

The joints between the articular facets, called facet joints, allow for some gliding motions between the vertebrae. They are strengthened by several ligaments:

Answer 11

Question 12

The __ __ ligament is most susceptible to stretching or tearing during a whiplash injury.

Answer 12

The anterior longitudinal ligament is most susceptible to stretching or tearing during a whiplash injury.

Question 13

__-__ joints consist of an articulation between the spine and the cranium. They permit motion in multiple planes stabilized by anterior and posterior atlanto-occipital membranes.

Answer 13

atlanto-occipital joints consist of an articulation between the spine and the cranium. They permit motion in multiple planes stabilized by anterior and posterior atlanto-occipital membranes.

Question 14

The atlanto-axial joints are stabilized by ligaments:

1. __ ligaments of the atlas (with longitudinal fascicles = cruciate ligaments of the atlas)
2. • __ ligaments
3. __ membrane (posterior longitudinal l.)
4. __ ligament (supraspinous l.)

Answer 14

The atlanto-axial joints are stabilized by ligaments:

1. transverse ligaments of the atlas (with longitudinal fascicles = cruciate ligaments of the atlas)
2. • alar ligaments
3. tectorial membrane (posterior longitudinal l.)
4. nuchal ligament (supraspinous l.)

Question 15

Answer 15

Question 16

Answer 16

Question 17

Answer 17

Question 18

Answer 18

Question 19

Each spinal cord segment has four roots: an anterior (ventral) and posterior (dorsal) root on both right and left sides.

• the anterior/ventral root contains efferent nerve fibres, which carry stimuli away
  from the CNStowards their target structures (motor)
• The posterior/dorsal root contains afferent nerve fibres, which return sensory
  information from the trunk and limbs to the CNS.

The anterior and posterior roots join to form the spinal nerve proper, containing a
mixture of sensory, motor, and autonomic fibers.

Answer 19

Each spinal cord segment has four roots: an anterior (ventral) and posterior (dorsal) root on both right and left sides.

• the anterior/ventral root contains __ nerve fibres, which carry stimuli __
• *from the __** towards their target structures (motor)
• The posterior/dorsal root contains __ nerve fibres, which return sensory
  information from the trunk and limbs to the CNS.

The anterior and posterior roots join to form the __ __ proper, containing a
mixture of sensory, motor, and autonomic fibers.

Question 20

Having exited the vertebral canal, the spinal nerve divides into two branches (this is not the same as the original anterior motor and posterior sensory roots on the spinal cord) : a larger anterior or
ventral ramus, and a smaller posterior orposterior/dorsal ramus.

-Anterior/ventral ramus innervates the skin and muscle on the anterior aspect of the trunk (
innervate the hypaxial musculature, including the limb musculature that sits on the trunk)

• Posterior/dorsal ramus innervates the post-vertebral muscles and the skin of the back. (
  innervate the epaxial musculature)

Answer 20

-Anterior/ventral ramus innervates the skin and muscle on the __ aspect of the trunk (
innervate the __ musculature, including the __ musculature that sits on the trunk)

• Posterior/dorsal ramus innervates the __-__ muscles and the skin of the back. (
  innervate the __ musculature)

Question 22

Note- the anterior and posterior muscles of the trunk are innervated by spinal nerves, with one
exception: the Accessory nerve- Cranial Nerve XI (1 out of 12 paired nerves that originate directly from
the brain) innervates the trapezius and sternocleidomastoid muscles

Answer 22

Note- the anterior and posterior muscles of the trunk are innervated by spinal nerves, with one
exception: the __ nerve- Cranial Nerve XI (1 out of 12 paired nerves that originate directly from
the brain) innervates the trapezius and __ muscles

Question 23

. The spinal nerves that arise from the end of the spinal cord are bundled together, forming a structure known as the __ __.

Answer 23

. The spinal nerves that arise from the end of the spinal cord are bundled together, forming a structure known as the cauda equina.

Question 24

Two swellings occur in the regions of the spinal cord that innervate the limbs:

The cervical enlargement is located proximally, at the __-T__ level. It represents the origin of the __ plexus. Between T-__and L_ is the lumbar enlargement, representing the origin of the _ and _ plexi.

Answer 24

The cervical enlargement is located proximally, at the C4-T1 level. It represents the origin of the brachial plexus. Between T11 and L1 is the lumbar enlargement, representing the origin of the lumbar and sacral plexi.

Question 25

The spinal meninges are three membranes that surround the spinal cord – the dura mater, arachnoid mater, and pia mater (order, superficial to deep). Distally, the meninges form a strand of fibrous tissue, the **\_\_ \_\_,** which attaches to the vertebral bodies of the coccyx. It acts as an anchor for the spinal cord and meninges. . **The __ \_\_** is an extension of the **\_\_ mate**r that descends within the lumbar vertebral foramen.

Answer 25

Distally, the meninges form a strand of fibrous tissue, the **filum terminale,** which attaches to the vertebral bodies of the coccyx. It acts as an anchor for the spinal cord and meninges. . **The filum terminale** is an extension of the **pia mate**r that descends within the lumbar vertebral foramen.

Question 26

The spinal dura mater is the most external of the meninges. It extends from the **\_\_** **\_\_** to the **\_\_** **\_\_**, separated from the walls of the vertebral canal by the epidural space. This space contains some loose connective tissue, and the internal vertebral venous plexus.

Answer 26

The spinal dura mater is the most external of the meninges. It extends from the **foramen** **magnum** to the **filum** **terminale**, separated from the walls of the vertebral canal by the epidural space. This space contains some loose connective tissue, and the internal vertebral venous plexus.

Question 27

The spinal __ mater is a delicate membrane, located between the dura mater and the pia mater. Cerebrospinal fluid (CSF) circulates deep to this meningeal layer.

Answer 27

**The spinal arachnoid mater** is a delicate membrane, located between the dura mater and the pia mater. Cerebrospinal fluid (CSF) circulates deep to this meningeal layer.

Question 28

The spinal pia mater is the innermost of the meninges. It is a thin membrane that covers the spinal cord, nerve roots and their blood vessels. **Inferiorly, the spinal pia mater fuses with the filum terminale.** Between the nerve roots, the pia mater thickens to form the **\_\_\_\_. T**hese ligaments attach to the dura mater – suspending the spinal cord in the vertebral canal.

Answer 28

The spinal pia mater is the innermost of the meninges. It is a thin membrane that covers the spinal cord, nerve roots and their blood vessels. **Inferiorly, the spinal pia mater fuses with the filum terminale.** Between the nerve roots, the pia mater thickens to form the **denticulate ligaments**. These ligaments attach to the dura mater – suspending the spinal cord in the vertebral canal.

Question 29

Answer 29