PTA 220 - Exam 6 (Chapters 14 & 15)

temporomandibular joint (TMJ)

- articulation between the cranium and the mandible

- most frequently used joint in the body

- there are 2 of them

- 1500-2000 movements a day

- synovial hinge joint

mandibular movements

elevation (mouth closed)

depression (mouth open)

protrusion/protraction (jaw forward)

retrusion/retraction (jaw backward)

lateral deviation (jaw side to side)

normal resting position

lips closed, teeth not touching

what muscles close the mouth?

temporalis & masseter

what muscles are secondary closers of the mouth?

medial or internal pterygoid

what muscle performs mandibular protrusion (protraction)?

lateral pterygoid, medial pterygoid

hyoids

depressors at the bottom of the mouth

what muscles perform mandibular elevation?

temporalis, massester, medial pterygoid

what muscle performs mandibular depression?

lateral pteryoid

what muscles perform mandibular protrusion?

lateral pterygoid, medial pterygoid

what muscle performs mandibular retrusion?

temporalis (posterior)

what muscles perform ipsilateral lateral deviation?

temporalis, masseter

what muscles perform contralateral lateral deviation?

medial pterygoid, lateral pterygoid

what muscles perform head flexion?

prevertebral group

what muscles perform head extension?

suboccipital group

facet

joints between each of the transverse processes; small, smooth, flat surface on a bone

costal facet

joints where the ribs connect to the thoracic vertebrae

lamina

connects spinous and transverse processes;

Posterior portion of the neural arch that unites from each side in the midline

pedicle

connects body and transverse process;

portion of the neural arch just posterior to the body and anterior to the lamina

annulus fibrosus

The outer portion of the disk consisting of several concentrically arranged fibrocartilaginous rings that serve to contain the nucleus pulposus

nucleus pulposus

pulpy, gelatinous substance with a high water content in the center of the disk

Atlas (C1)

the first cervical vertebra upon the cranium rests, supports the globe of the head

Axis (C2)

the second cervical vertebra, forms the pivot that allows rotation of the atlas

dens (odontoid process)

takes the place of the vertebral body that exists at the other levels below C2, cervical rotation occurs through its articulation with the atlas

C7 (vertebra prominens)

has a long and prominent spinous process

ALL (anterior longitudinal ligament)

prevents excessive hyperextension

PLL (posterior longitudinal ligament)

prevents excessive flexion

ligamentum flavum

creates the posterior border of the vertebral canal by connecting adjacent laminae anteriorly

ligamentum nuchae

takes place of supraspinal and interspinal ligaments in cervical region

erector spinae

longisimus, iliocostalis, spinalis

linea alba

provides attachment for the transverse abdominis and 2 oblique muscles

kyphosis

an increase in the curvature of the thoracic spine in the sagittal plane

lordosis

an increase in curvature of the lumbar spine in the sagittal plane

what muscles make up the erector spinae group?

iliocostalis, longissimus, spinalis

the suboccipital muscles perform what motions of the head?

extension, lateral bending, same side rotation

what is the origin of the temporalis muscle?

temporal fossa

what is the insertion of the temporalis muscle?

coronoid process and ramus of mandible

action of the temporalis muscle

bilaterally: elevation, retrusion

unilaterally: ipsilateral lateral deviation

what is the origin of the masseter muscle?

zygomatic arch of temporal bone/zygomatic process of maxilla

what is the insertion of the masseter muscle?

angle of the ramus and coronoid process of mandible

action of the masseter muscle?

bilaterally: elevation

unilaterally: ipsilateral lateral bending

what neck & trunk motions occur in the sagittal plane around a frontal axis?

flexion, extension, hyperextension

what neck & trunk motion occurs in the frontal plane around a sagittal axis?

lateral bending

what neck & trunk motion occurs in the transverse plane around a vertical axis?

rotation

anterior neck muscles

Sternocleidomastoid, Scalenes (3), Prevertebral group (4)

anterior trunk muscles

rectus abdominis, external oblique, internal oblique, transverse abdominis

posterior neck muscles

erector spinae group (3), splenius capitus, splenius cervicis, suboccipital group (4)

posterior trunk muscles

erector spinae group (3), transversospinalis group (3), interspinales, intertransversarii

lateral trunk muscle

quadratus lumborum

what muscles do capital flexion?

prevertebral group

what muscles do capital extension?

suboccipital group

what muscle does cervical flexion?

sternocleidomastoid

what muscles do cervical extension?

splenius capitis, splenius cervicis, erector spine, transversospinalis, interspinales

what muscles do cervical lateral bending?

sternocleidomastoid, splenius capitis, splenius cervicis, scalenes, erector spinae, intertransversarii

what muscles do cervical rotation (same side)?

splenius capitis, splenius cervicis

what muscles do cervical rotation (opposite side)?

sternocleidomastoid, transversospinalis

what muscles do trunk flexion?

rectus abdominis, external oblique, internal oblique

what muscles do trunk extension?

erector spinae, transversopsinalis, interspinales

what muscles do trunk lateral bending?

quadratus lumborum, erector spinae, internal oblique, external oblique, intertransversarii

what muscle does trunk rotation (same side)?

internal oblique

what muscle does trunk rotation (opposite side)?

external oblique, transversospinalis

what muscles do compression of the abdomen?

rectus abdominis, external oblique, internal oblique, transverse abdominis

what absorbs the majority of your body weight

lumbar spine

ROM

cervical flexion: 40°

cervical extension: 50-70°

cervical lateral bending: 20°

cervical rotation: 50°

trunk flexion: 10 cm

trunk extension: 4-6 cm

trunk rotation: 45°

trunk lateral bending: 35°

what muscle is our major bilateral cervical flexor but it also bilaterally extends the head?

sternocleidomastoid

scalenes

do lateral bending