Back muscles - lateral tract
Aus Dornheim Anatomy
Version vom 5. Januar 2021, 14:13 Uhr von Becher (Diskussion | Beiträge)
The lateral tract is made up of a complex of long muscles. A distinction is made between the saccrospinal (m. iliocostalis and m. longissimus), spinotransversal (mm. intertransversarii and levatores costarum) and intertransversal (mm. intertransversarii and levatores costarum) system.
Inhaltsverzeichnis
Sacrospinal System
| M. iliocostalis | M. longissimus | |
| Origin | 1) M. iliocostalis lumborum: fascia thoracolumbalis, os sacrum, crista iliaca 2) M. iliocostalis thoracis: 7th-12th rib 3) M. iliocostalis cervicis: 3rd-7th rib |
4) M. longissimus thoracis: spinous processes of the lumbar spine, transverse processes of the lower section of the thoracic spine, os sacrum, crista iliaca 5) M. longissimus cervicis: 1st-6th thoracic vertebrae (transverse processes) 6) M. longissimus capitis: 1st-3rd thoracic vertebrae (transverse processes) and 4th-7th cervical vertebrae (transverse and articular processes) |
| Insertion | 1) 6th-12th rib, transverse processes of the upper lumbar spine, fascia thoracolumbalis 2) 1st-6th rib 3) 4th-6th cervical vertebrae (transverse processes) |
4) 2th-12th rib, transverse processes of the thoracic spine, rib processes of the lumbar spine 5) 2nd-5th cervical vertebrae (transverse processes) 6) Wart process (proc. mastoideus) of the temporal bone (os temporale) |
| Function | In case of one-sided contraction these muscles cause lateral flexion on the same side of the body (ipsilateral), in case of bilateral activation dorsal extension. | The m. longissimus additionally causes a rotation of the head to the ipsilateral side. |
| Innervation | lateral branches of the rami posteriores spinal nerves (C8-L1) | lateral branches of the rami posteriores spinal nerves (C1-L5) |
Spinotransverse and intertransverse system
Muscles:
| M. splenius | Mm. intertransversarii | Mm. levatores costarum | |
| Origin | 7) M. splenius cervicis: 3rd-6th thoracic vertebra (spinous processes) 8) M. splenius capitis: 3rd cervical to 3rd thoracic vertebra (spinous processes) |
9) Mm. intertransversarii mediales lumborum: between adjacent procc. mamillares of the lumbar spine 10) Mm. intertransversarii laterales lumborum: between adjacent procc. costales of the lumbar spine 11) Mm. intertransversarii posteriores cervicis: between adjacent tubercula posteriora of the 2nd-7th cervical vertebra |
12) Mm. intertransversarii costarum breves: 7. Hals- und 1.-11. Brustwirbel (Querfortsätze) 13) Mm. intertransversarii costarum longi: 7th cervical and 1st-11th thoracic vertebrae (transverse processes) |
| Insertion | 7) 1st and 2nd cervical vertebrae (spinous processes) 8) Proc. mastoideus, upper cervical line (lateral Linea nuchalis | 9) to 11) insertion and origins are congruent | 12) Rib angle (Angulus costae) of the underlying rib 13) Rib angle (Angulus costae) of the next but one rib |
| Function | In case of bilateral activation these muscles cause a dorsal extension of the cervical spine, in case of one-sided contraction rotation and ipsilateral lateral flexion. | One-sided activation of these muscles leads to lateral flexion of the lumbar and cervical spine, bilateral contraction to stabilization and dorsal extension of the lumbar and cervical spine | Both-sided contraction causes dorsal extension of the thoracic spine, one-sided contraction causes ipsilateral flexion and contralateral rotation. |
| Innervation | lateral branches of the rami posteriores spinal nerves (C1-C6) | lateral branches of the rami posteriores and the corresponding spinal cord segment | rami posteriores spinal nerves |
Free exploration
Look at the location of the back muscles in 3D and explore them freely. Afterwards, you can check your learned knowledge through the exercise tasks.
