Miscellaneous Musculoskeletal

Question 1

Where does the dorsal ramus innervate, and where does the ventral ramus innervate?

Answer 1

Dorsal ramus innervates the back. Ventral ramus innervate the anterior and lateral trunk and limbs

Question 2

What is the role of somatic motor neurons?

Answer 2

Innervate and send info to skeletal muscle to cause movement

Question 3

What is the role of somatic sensory neurons

Answer 3

Collect info from skin, joints, ligaments, and muscles and bring it back to the central nervous system at the spinal cord

Question 4

Explain the origin of dorsal and ventral rami

Answer 4

Spinal cord branches off into spinal nerves (somatic motor neurons AND somatic sensory neurons)

–> Spinal nerves branch into dorsal ramus and ventral ramus

–> Dorsal ramus goes to posterior, whilst ventral ramus goes to anterior and limbs

Question 5

What are nerve plexi?

Answer 5

Networks of nerve fibres innervating the upper and lower limb. E.g. the lumbosacral plexus of fibres innervating the pelvis and lower limb’s skin and muecles, and the brachial plexus of fibers innervating the shoulders and upper limb’s skin and muscles

Question 6

What is the lumbosacral plexus? What peripheral nerves does it contribute to?

Answer 6

Network of nerve fibres innervating the pelvis and lower limb’s skin and muscles

Branches into obturator nerve (innervates medial thigh), sciatic nerve (innervates posterior thigh and divides into nerves which innervate the foot and lower leg), and femoral nerve (innervates anterior thigh)

Question 7

What is the brachial plexus? What peripheral nerves does it contribute to?

Answer 7

Network of nerve fibres innervating the shoulders and upper limb’s skin and muscles

Branches into radial nerve (extensor muscles of posterior brachia and antebrachia), axillary nerve (lateral muscles of brachia and antebrachia, including deltoid and teres minor), and musculoskeletal nerve (anterior muscles of brachia and antebrachia)