Back (O/i/n) - Group 1

Front 1

Trapezius

Back 1

(O) (1) Medial third of superior nuchal line, (2) external occipital protuberance, (3) nuchal ligament, (4) spinous processes of C7–T12 vertebrae (I) (1) Lateral third of clavicle, (2) acromion, and (3) spine of scapula (N) Motor: spinal accessory n. (CN XI), Sensory: C3, C4 spinal nn.

Front 2

Latissimus dorsi

Back 2

(O) (1) Spinous processes of T7-T12, (2) thoracolumbar fascia, (3) iliac crest, (4) inferior 3-4 ribs (I) Floor of intertubercular groove of humerus (N) Thoracodorsal n. (C6, C7, C8)

Front 3

Levator scapulae

Back 3

(O) Posterior tubercles of transverse processes of C1-C4 vertebrae (I) Medial border of scapula (superior to root of the spine of scapula) (N) Dorsal scapular n. (C5), Cervical nn. (C3, C4)

Front 4

Rhomboid major

Back 4

(O) Spinous processes of T2-T5 (I) Medial border of scapula (from level of the spine of the scapula to the inferior angle) (N) Dorsal scapular n. (C4, C5)

Front 5

Rhomboid minor

Back 5

(O) (1) Nuchal l., (2) spinous processes of C7 and T1 vertebrae (I) Triangular area at the medial end of the scapular spine (N) Dorsal scapular n. (C4, C5)

Front 6

Serratus posterior inferior

Back 6

(O) Spinous processes of T11-L2 (I) Inferior borders of 8th to 12th ribs (near their angles) (N) 9th-11th intercostal nn. subcostal n. (T12)

Front 7

Serratus posterior superior

Back 7

(O) (1) Nuchal l., (2) spinous processes of C7-T3 (I) Superior borders of 2nd to 4th ribs (N) 2nd-5th intercostal nn.

Front 8

Splenius capitis

Back 8

(O) Nuchal ligament, spinous processes of C7-T6 (I) Mastoid process of temporal bone, lateral third of superior nuchal line of occipital bone (N) Posterior rami of spinal nn.

Front 9

Splenius cervicis

Back 9

(O) Nuchal ligament, spinous processes of C7-T6 (I) Tubercles of transverse processes of C1-C3 or C4 vertebrae (N) Posterior rami of spinal nn.

Front 10

Iliocostalis

Back 10

(O) Arises by broad tendon from (1) posterior part of iliac crest, (2) posterior surface of sacrum, (3) sacro-iliac ll., (4) sacral and (5) inferior lumbar spinous processes, and (6) supraspinous l. (I) Angles of lower ribs and cervical transverse processes - (lumborum, thoracis, and cervicis) (N) Posterior rami of spinal nn.

Front 11

Longissimus

Back 11

(O) Arises by broad tendon from (1) posterior part of iliac crest, (2) posterior surface of sacrum, (3) sacro-iliac ll., (4) sacral and (5) inferior lumbar spinous processes, and (6) supraspinous l. (I) Ribs (between tubercles and angles), transverse processes in thoracic and cervical regions, mastoid process of temporal bone - (thoracis, cervicis, capitis) (N) Posterior rami of spinal nn.

Front 12

Spinalis

Back 12

(O) Arises by broad tendon from (1) posterior part of iliac crest, (2) posterior surface of sacrum, (3) sacro-iliac ll., (4) sacral and (5) inferior lumbar spinous processes, and (6) supraspinous l. (I) Spinous processes in upper thoracic region, cranium - (thoracis, cervicis, capitis) (N) Posterior rami of spinal nn.

Front 13

Semispinalis

Back 13

(O) Transverse processes of C4-T10 vertebrae (I) Occipital bone, spinous processes of upper thoracic and cervical regions (four to six segments) - (thoracis, cervicis, and capitis) (N) Posterior rami of spinal nn.