Deep muscles of the back

This tutorial explores the anatomy of the back muscles, focusing on the intrinsic muscles divided into layers: superficial, intermediate, deep, and deepest. It covers the specific muscles within each layer, their origins, insertions, innervations, and functions. The tutorial also discusses clinical aspects of back strain, its causes, symptoms, and prevention strategies. The content is structured to aid in understanding and memorizing the complex anatomy of the back muscles.

What are the two main ways to categorize the intrinsic muscles of the back?

• By color and size

• By origin and insertion

• By tracks and layers

• By function and location

Which muscles make up the superficial layer of the intrinsic back muscles?

• Interspinales and intertransversarii

• Splenius capitis and splenius cervicis

• Transversospinalis muscles

• Erector spinae muscles

What is the primary function of the splenius capitis muscle?

• Stabilizes the thoracic spine

• Flexes the lumbar spine

• Elevates the ribs

• Extends and rotates the head

Which muscle group is part of the intermediate layer of the intrinsic back muscles?

• Erector spinae

• Levatores costarum

• Splenius muscles

• Transversospinalis group

What are the three columns of the erector spinae muscle group?

• Iliocostalis, longissimus, spinalis

• Interspinales, intertransversarii, levatores costarum

• Splenius capitis, splenius cervicis, splenius thoracis

• Semispinalis, multifidus, rotatores

Which muscle is NOT part of the transversospinalis group?

• Semispinalis

• Iliocostalis

• Multifidus

• Rotatores

What is the function of the multifidus muscle during unilateral contraction?

• Extends the spine

• Rotates the spine to the opposite side

• Flexes the head

• Elevates the ribs

Which muscles are found in the deepest layer of the back?

• Iliocostalis, longissimus, spinalis

• Semispinalis, multifidus, rotatores

• Splenius capitis, splenius cervicis

• Interspinales, intertransversarii, levatores costarum

What is a common cause of back strain?

• Overstretching of back muscles

• Lifting weights with proper form

• Sleeping on a firm mattress

• Regular exercise

Which muscle group is most often involved in back strain?

• Transversospinalis group

• Interspinales

• Erector spinae

• Levatores costarum