The Back OUTLINE Vertebral Column (review) Craniovertebral Joints Dorsal Scapular Region(review) Muscles of the Back Suboccipital Region Dept. of Human Anatomy, Si Chuan University Zhou hongying eaglezhyxzy@163.com
Bony structures of the back - posterior basal regions of the skull - vertebral column - proximal parts of the ribs - superior aspect of the pelvic bone
Surface anatomy of the back external occipital protuberance sup. & inf. nuchal lines spine of scapula spinous processes iliac crest
Vertebral Column: 33 vertebrae, 5 regions
Features of A Typical Vertebra & Regional Characteristics of Vertebrae
Intervertebral Foramen & Vertebral Canal
The Connections of Vertebral Column zygapophyseal joint intervertebral disc ligaments
Craniovertebral Joints atlanto-occipital joints median atlanto-axial joint lateral atlanto-axial joints
Craniovertebral Joints
Movements of Craniovertebral Joints
External Craniocervical Ligaments Anterior Atlanto-occipital Membrane Posterior Atlanto-occipital Membrane
Tectorial Membrane Internal Craniocervical Ligaments
cruciate ligament/transverse ligament alar ligament apical ligament
CLINICAL NOTES Rupture of transverse ligament & dens
The Continuations of the Fibrous Structures anterior longitudinal ligament ant. atlanto-occipital & atlanto-axial membrane posterior longitudinal ligament tectorial membrane ligamentum flavum post. atlanto-occipital & atlanto-axial membrane
Superficial structures of the back skin: hair follicle, sebiferous gland, sweat glands fascia: - superficial fascia - deep fascia thoracolumbar (lumbodorsal) fascia covers the deep muscles of the back & trunk
Level of LV5 Level of Renal Hilum The Thoracolumbar Fascia
Overview of Back Muscles extrinsic back muscles: - trapezius & latissimus dorsi - levator muscle of scapula - rhomboideus - serratus posterior (sup. & infer.) intrinsic back muscles: - superficial layer - intermediate layer - deep layer - minor deep layer
Extrinsic Back Muscles trapezius m. latissimus dorsi m. levator scapulae m. rhomboids m. serratus post. (sup. & inf.)
The Intrinsic Back Muscles superficial layer - splenius capitis & cervicis intermediate layer (erector spinae m.) - iliocostalis, longissimus & spinalis
The Intrinsic Back Muscles
Multifidus Semispinalis Rotatores deep layer (transversospinales) - semispinalis, multifidus & rotatores
The Back Muscles (Deep Layer)
minor deep layer - interspinales - intertransversarii - levatores costorum Back Muscles (Deep & Minor Deep Layers)
Thoracolumbar Fascia & Back Muscles
The Layers of Back Muscles note that the erector spinae muscles is in three columns and that the transversospinal muscles is in three layers.
Superior Lumbar Triangle 12th rib lateral margin of erector spinae m. posterior margin of internal oblique m. CLINICAL NOTES Superior & Inferior Lumbar Herniation (Inferior) Lumbar Triangle iliac crest inferior portion of anterior margin of latissimus dorsi posterior margin of external oblique m.
Innervation of the Back Muscles extrinsic muscles are innervated by anterior rami of spinal nevers except trapezius which is innervated by accessory never intrinsic muscles are innervated by posterior rami of spinal nevers
Functions of the Back Muscles
suprascapular a. & n. dorsal scapular a. & n. Dorsal Scapular Region
The Suboccipital Triangle (Region) boundaries - superomedially: rectus capitis posterior major & minor - superolaterally: obliquus capitis superior - inferolaterally: obliquus capitis inferior - floor: posterior atlantooccipital membrane & posterior arch of C1 - roof: semispinalis capitis
The Suboccipital Triangle contents - vertebral artery - suboccipital nerve - deep cervical vein
- vertebral artery - suboccipital nerve - greater occipital nerve
Neurovascular Supply of Back extrinsic muscles are innervated by anterior rami of spinal nerves except trapezius which is innervated by accessory nerve intrinsic muscles are innervated by posterior rami of spinal nerves
Guide to Dissection remove the skin follow the incisions above clean the superficial fascia, then identify the superficial back muscles
observe (serratus posterior superior & inferior), then have them cut vertically
observe the splenius (capitis & cervicis) and erector spinae m. (iliocostalis, longissimus & spinalis).
identify the semispinalis capitis & greater occipital nerve use blunt dissection to trace the greater occipital nerve deeply through the semispinalis capitis muscle. detach the semispinalis capitis muscle and reflect it inferiorly. preserve the greater occipital nerve. follow the greater occipital nerve to the lower border of the obliquus capitis inferior muscle Identify and clean the three muscles that form the boundaries of the suboccipital triangle