Contractile muscles

What is the function of intrinsic superficial & intermediate muscles

• Prime movers

• Resist gravity

• More involved in preventing shearing/accessory movements "stabilisers"

• Spans lesser segments than the erector spinae

• Can apply a compressive force to IVJs, & facets

Functions of deep intrinsic transversospinalis muscles

• Run in oblique direction

• Spinous process to transverse process

• Produce power

• Sits closer to axis of movement

• Span many vertebral layers

All the intrinsic superficial & intermediate muscles does unilateral lateral flexion and bilateral neck extension

• True

• False

Longissimus and iliocostalis has the same inferior attachment

• True

• False

Apart from lateral flexion, neck and back extension, what other action does iliocostalis do?

Apart from lateral flexion, what other unilateral action does splenius capitis and cervicis do?

Which region is multifidus most developed in?

Which region is rotatores most well developed in?

Which muscle is a fixator of 12th rib during respiration?

• Multifidus

• Rotatores

• Quadratus lumborum

• Interspinalis

• Semispinalis

Which muscles stabilise the vertebrae during local movements of vertebral column and trunk?

• Semispinalis

• Multifidus

• Rotatores

• Interspinalis

• Quadratus lumborum