PRE-MIDSEM

Question 1

A muscle’s action can chance in different joint positions. How does this statement apply to gluteus medius?

Answer 1

In 0 degrees flexion:

• anterior compartment = medial moment arm
• middle and posterior compartment = lateral moment arm

As hip flexors:

• anterior compartment = medial moment arm
• middle and posterior compartment = medial moment arm

Question 2

what affect does the difference in length of the articular surfaces of the lateral and medial femoral condyles have on tiobiofemoral joint movement?

Answer 2

= there is longer articular surface on medial femoral condyle
this facilitates the ‘screw home mechanism’ : thus, in extension there is IR/MR of femur on tibia

Question 3

What gives stability in anatomical position to the knee

Answer 3

1. Screw home mechanism
2. Extensor moment
3. Shape of femoral condyles

Question 4

List 2 functions of the spinal cord

Answer 4

1. Conduit function (pathways)

2. Intrinsic function (processing)

Question 5

Conus medullaris - at which vertebral level

Answer 5

L1/L2

Question 6

Filum terminale - what is it and what does it attach too?

Answer 6

= a delicate strand of fibrous tissue (20cm) and attaches to first segment of coccyx

Question 7

Cauda equina - what is it comprised of?

Answer 7

bundle of spinal nerves and spinal nerve rootlets

Question 8

Lumbar cistern - what is this?

Answer 8

subarachnoid space in the lower lumbar spinal canal

Question 9

Explain the arrangement of the spinal nerves to the vertebrae as they enter/exit the vertebral canal via the intervertebral foramen

Answer 9

C1 - C7 spinal nerves: pass ABOVE corresponding pedicle

C8 and below: pass BELOW corresponding pedicle

Question 10

List the 3 steps of the simplified hierarchical organisation of the SENSORY cortices

Answer 10

1. Primary sensory cortex (PSC) receives sensory information from the thalamus
2. PSC conveys information to the secondary association cortex for interpretation
3. Multiple secondary association cortices send their sensory information to the multimodal posterior association area for integration

Question 11

List the 3 steps of the simplified hierarchical organisation of the MOTOR cortices

Answer 11

1. Motor command is initiated in the brain and exits via the primary motor cortex (M1)
2. The prefrontal cortex/anterior association area generates motor commands and transfers them to secondary motor cortices (SMC and PMC) for purposes of integration of motor skills
3. Secondary association cortices (SMC and PMC) transfer the motor command to the primary motor cortex (M1) for execution.