530 likes | 748 Views
Muscles of the Spinal Column. Chapter 12. Cervical Muscles. Splenius (capitis and cervicis). Origin: Cervicis – spinous process of T3-T6 Capitis - lower half of ligmentum nuchea & spinous process of C7 and T1-3. Insertion: Cervicis - transverse process of C1-C3.
E N D
Muscles of the Spinal Column Chapter 12
Splenius (capitis and cervicis) • Origin: • Cervicis – spinous process of T3-T6 • Capitis - lower half of ligmentum nuchea & spinous process of C7 and T1-3. • Insertion: • Cervicis - transverse process of C1-C3. • Capitis – mastoid process and occipital bone • Actions: • Whole • Cervical Extension • Half • Cervical Rotation to the same side. • Cervical Lateral flexion
Sternocleidomastoid • O: Top of the sternum and medial third of the clavical • I: Mastoid process • Action: • Whole • Cervical Flexion • Half • Cervical Lateral Flexion • Cervical Rotation to the opposite side.
Scalenes (or scaleni) • O: First two ribs • I: Transverse processes of cervical vertebrae. • Actions: • Whole – Cervical Flexion • Half - Cervical Lateral Flexion (help with inhalation during exercise)
Erector spinae muscles • O: Fascia of lower back, posterior L, T and lower C vertebrea, and angles of ribs. • Inesrtions • Spinalis branch - spinous process of T and C and occipital bone • Longissimus branch - transverse process of T and C, mastoid process. • Iliocostalis branch - angles of the ribs and cervical transverse processes • Actions: • Whole – Extension • Half - Lateral flexion
Erector spinae muscles • Iliocostalis branchLongissimus branchSpinalis branch
Quadratus lumborum • O: Posterior lip of iliac crest • I: Lower border of 12th rib and transverse process of L1-4 • Actions: • Half - Lumbar lateral flexion • Whole - Stabilization
Iliopsoas • O: • Psoas - lateral surface of T12 and L1-5, • Iliacus - anterior surface of ilium (iliac fossa) • I: Lesser trochanter of femur • Action: • Whole - Lumbar flexion of trunk • [Whole - Hip flexion]
The Abdominal Muscles 4. 2. 3. 1.
Rectus abdominis • O: Crest of the pubis • I: Xyphoid process and 5th - 7th ribs • Action: • Whole • Lumbar Flexion • Half • Lumbar lateral flexion
External oblique • O: Lower 8 ribs. • I: Anterior iliac crest; inguinal ligament, crest of pubis, fascia of the rectus abdominus • Action: • Whole – Lumbar flexion • Half • Lumbar rotation to opposite side • Lumbar lateral flexion
Internal oblique • O: Inguinal ligament (from anterior iliac crest to pubis) and iliac crest • I: Costal cartilages of the lower ribs. • Actions: • Whole – Lumbar flexion • Half • Lumbar rotation to the same side • Lumbar lateral flexion
Internal The Oblique Muscles? Which is Internal and which is External? External
Transverse abdominis • I: Inguinal ligament, iliac crest, and lower 6 ribs • O: Linea alba ("white line") and pubis crest • Functions: • Exhalation (during exercise)
MUSCLES OF RESPIRATION • Rib actions • Respiration
Diaphragm • O: Xiphoid process, costal cartilages, lumbar vertebrae • I: Central tendon • A: Flattens, pulls central tendon downward
External Intercostals • O: Inferior border of the ribs • I: Superior border of the next rib below • A: Draws ribs together and lifts the ribs • 11 on each side; slant down and forward
Internal Intercostals (p. 379) • O: Inferior border of the ribs • I: Superior border of the next rib down • A: Draws ribs together and lowers ribs • slant down and backward
MUSCLES OF RESPIRATION Inspiration Rib (with Intercostal Muscles) Diaphragm Expiration
I. INSPRIATION • Increase in thorasic cage • Volume inside increases • Pressure decreases • Air moves into the lungs
1. Diaphragm Flattens and moves downward when contracted A. Inspiration at Rest
A. Inspiration at Rest • 1. Diaphragm • Flattens and moves downward when contracted • 2. External Intercostals • Lift the ribs up and out when contracted
B. Inspiration During Exercise • 1. Scalenes – elevate upper ribs • 2. Sternoceidomastoid – elevate clavical and upper ribs • 3. External intercostal muscles
II. EXPIRATION • Decrease thorasic cage • Volume inside decreases • Pressure increases • Air moves out of the lungs
A. Expiration at Rest. • No muscles are involved • Passive recoil action at rest will decrease the thorasic cage
B. Expiration During Exercise • Internal Intercostals - • Rectus Abdominus – help push the diaphragm upward. • External obliques– help push the diaphragm upward. • Internal obliques– help push the diaphragm upward. • Transverse abdominus– help push the diaphragm upward.
*Sternocleidomastoid Muslces of Expiration *Scalenes *Internal Intercostals External Intercostals *Rectus Abdominus Diaphragm *External Obliques *Internal Obliques *Transverse Abdominus Muscles of Inspiration