The muscles of the back can be arranged right into 3 categories based on their location:

Not attached come the thoracic spine, but an essential group of muscle in this region is the Intercostal team ie exterior Intercostals; interior Intercostals.

Major Muscles


Superficial Layer

Trapezius – this large back muscle attaches come the vertebral column from the base of the skull to the ligamentum nuchae of the neck, to the spinous procedures of C7 and also the thoracic spine down to T12. That connects the shoulder blade v the vertebral column and also acts to assistance the arm and also assist in top limb motion by managing shoulder tongue movements.

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Latissimus Dorsi – this large back muscle runs from the spinous procedures of the reduced thoracic vertebrae and lumbar spine, the connective organization (fascia) of the thoracolumbar region, as well as the pelvis and also lower ribs, to insert right into the top arm bone (humerus). Its primary action is to extend, adduct and internally turn the top arm (i.e. Carry the top arm backwards, come the side of the body and rotate the top arm in the direction of the human body e.g. Performing a chin up). It also influences activities of the shoulder blade and also trunk.

Rhomboids – these rhombus shaped muscles originate from the spinous procedures of cervical and also thoracic vertebrae (C7 come T5) and also attach come the shoulder blade. The rhomboids main action is to traction the shoulder blades ago (scapular retraction).

Intermediate Layer


Serratus Posterior premium – is a thin, quadrilateral shaped muscle, located at the upper and also back part of the thoracic spine. It lies deep to the rhomboids and also aids catalyst by elevating ribs 2 come 5 wherein it attaches.


Serratus Posterior worse – is situated at the junction that the thoracic and also lumbar regions. It originates from vertebrae T12 down to L3 and also inserts into the ninth through come 12th ribs. The acts to attract the reduced ribs backwards and downwards and also assists in tribe rotation and also extension. It additionally helps with compelled expiration.

Back Muscles

The term paraspinal musculature is provided to explain the erector spinae and also the transversospinalis groups together. this muscles space the Intrinsic ago muscles, named therefore because your embryological advance begins in the back, protest to the superficial and also intermediate back muscles which build elsewhere and are because of this classed as extrinsic muscles.<1>


1.Thoracic Erector Spinae team ie Iliocostalis; Longissimus; Spinalis– the main extensor (backward bending) muscle of the thoracic spine, located on either next of the vertebral column.

The erector spinae is the primary musculature that works as soon as we bend forward. It contract eccentrically to guide our descent once we bending forward; it contract isometrically when we organize a bentforward posture; and also it contract concentrically once we stand back up. As soon as acting unilaterally (on only one side of the body) it assists with side bending and spinal rotation to the very same side.

2. Transversospinalis team – this shorter, deep muscles assist stabilise the spinal segments.

They are situated deep come the erector spinae, and also run obliquely and also makes increase the fixed of musculature that fills the laminar groove that the spine between the transverse and also spinous processes.The transversospinalis muscle team can be separated into 3 subgroups: indigenous superficial come deep, they space the semispinalis, rotatores and also the multifidus:The multifidus is the largest muscle the the low back; the semispinalis is the largest muscle of the neck. Additionally credited, together with the transversus abdominis, together being among the most vital muscles of main point stabilization.As the multifidus attaches inferiorly come the iliac crest and sacrum, the transversospinalis group can aid stabilize the sacroiliac joint.

The Intercostal Group


The intercostal group is created of the external intercostals and also the internal intercostals.

Located in the anterior, lateral, and also posterior thoracic region of the trunk.Depending top top the particular location, they might be deep to various other muscles or they may be superficial and also easily palpable.The fibre directions of these two muscle groups are perpendicular to each other.The fibre direction that the outside intercostals is the very same as the fibre direction of the external abdominal oblique

Clinical Implications

Many thoracic spine difficulties are connected to bad posture and/or muscle irritation or tension, likewise called myofascial pain.

These muscular troubles can arise native eg.

Preventing Thoracic Muscle Strains

Lift objects carefully. Ask someone to aid lift heavy objects. If you should lift an object by yourself, execute not usage your back muscles to lift. Lift v your legs.

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The 5 minute video below is the the back muscles in a nutshell.

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