BACK Vertebrae & Intrinsic Back Muscles

FALSE MEMORIES Sleep deprivation and false memories

BACK OBJECTIVES Describe the gross anatomy for each system (circulatory, muscular, nervous, and skeletal) in the region of the back. Integrate the systems to discuss the vertebral column functions. Analyze common dysfunctions in the vertebral column. For each muscle, describe how the attachment sites result in an action around a joint. For each muscle, identify the innervation (peripheral nerve and nerve roots).

THORACIC REGION Body shape, foramen shape Angles of spinous processes Costal facets Angles of zygapophysial joints ROM

COSTOVERTEBRAL JOINTS Head of rib – bodies of vertebrae Radiate ligaments Articulating surface of tubercle of rib – transverse process Non-articulating surface of tubercle of rib – costotransverse ligaments ROM

THORAX Rib 1 Rib 2 Manubrium, body, and xiphoid of sternum Cartilaginous costal joints ROM

LUMBAR REGION Body shape, foramen shape Spinous processes Transverse processes Angles of zygapophyseal joints ROM Mammillary and accessory processes

SACRUM Fused vertebrae No discs Body Ala Sacral promontory Foramina

SACRUM WITH PELVIS

LIGAMENTOUS SUPPORT Dense, parallel collagen fibers Ligaments strongly resist motion Ligaments vs. Joint capsules

LIGAMENTOUS SUPPORT OF VERTEBRAE Anterior longitudinal ligament Posterior longitudinal ligament Ligamenta flava (ligamentum flavum)

GENERAL SKELETAL STRUCTURE Gradual shape change

WHICH OF THE FOLLOWING IS INCORRECT PERTAINING TO THE THORACIC PART OF THE VERTEBRAL COLUMN? A.includes the most frequently fractured vertebra B.presence of costal facets C.Most vertebrae have horizontal spinous processes. D.articular facets that are most effective at limiting flexion E.Inferior vertebrae have mammillary processes.

WHICH OF THE FOLLOWING IS CORRECT PERTAINING TO THE LONGITUDINAL LIGAMENTS OF THE VERTEBRAL COLUMN? A.Both tend to limit hyperflexion. B.Both tend to limit hyperextension. C.The anterior limits hyperextension whereas the posterior limits hyperflexion. D.The anterior limits hyperflexion whereas the posterior limits hyperextension. E.Both limit lateral flexion.

WHICH ONE OF THE FOLLOWING ASSOCIATIONS IS INCORRECT? A.tectorial membrane—superior continuation of the posterior longitudinal ligament B.cruciate (cruciform) ligament—composed of the transverse ligament of the atlas and the longitudinal bands C.rupture of the transverse ligament of the atlas— atlantoaxial subluxation D.rupture of the alar ligaments—increased range in head movements E.fracture of the dens—anterior dislocation of C3—C5 vertebrae

BACK MUSCULATURE General muscle functions: movement, sensation, protection, metabolism General tendon functions: transfer muscle forces efficiently, sensation Actions Interactions Protective features Sensory features

SUBOCCIPITAL REGION Suboccipital Triangle  Borders, roof, floor  Verebral artery and suboccipital nerve 4 total suboccipital muscles Functions: mostly postural

DEEP LAYER OF INTRINSIC BACK MUSCLES Rotatores Multifidus Semispinalis Intertransversarii Interspinales Levator costarum

CROSS SECTION

DEEP POSTERIOR NECK MUSCLES Same deep intrinsic back muscles  Rotatores, intertransversarii, interspinales Semispinalis Capitis Semispinalis Cervicis Splenius Capitis Splenius Cervicis Sternocleidomastoid (SCM)

NECK ROTATION

YOUR PATIENT’S WORKSTATION MAKES HER LOOK TO THE RIGHT WHILE WORKING. WHICH MUSCLE WOULD BECOME TIGHT AND SHORT OVER TIME? A.R SCM B.L Obliquus capitis inferior C.R Semispinalis D.R Splenius

WHAT IS THE SUPEROMEDIAL BORDER OF THE SUBOCCIPITAL TRIANGLE? A.Obliquus capitis superior B.Obliquus capitis inferior C.Rectus capitis posterior minor D.Rectus capitis posterior major E.Semispinalis capitis