Chapter 11: Axial Muscles Flashcards

1
Q

Discuss axial muscles and the basic actions/motions they produce. (7)

A
  • Origins and insertions are on axial skeleton.
  • Support/move head and spinal column.
  • Assist in food processing (chewing and swallowing).
  • Aid breathing.
  • Support/protect abdominal and pelvic organs.
  • Nonverbal communication (facial expression).

-They do NOT move pectoral/pelvic girdle or limbs.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Define aponeurosis.

A

Flat sheet of connective tissue used for muscle insertion.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

List the 4 paired muscles of mastication.

A
  1. Temporalis (elevate/retract)
  2. Masseter (elevate/protract)
  3. Lateral pterygoids
  4. Medial pterygoids
    - both 3 & 4 protract and move mandible side to side for chewing
    - all innervated by cranial nerve V
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

List the 4 muscles of the abdominal wall and their function.

A
1. External  oblique 
    (most superficial of 3 lateral muscles)
2. Internal oblique 
    (middle of 3 lateral muscles)
3. Transverse abdominis 
    (deepest of 3 lateral muscles)
4. Rectus abdominis 
    (anterior, connecting to sternum and pubic bone; divided into 4 muscle segments)

Function:

  • Compress and hold abdominal muscles in place
  • Flex and stabilize vertebral column
  • Laterally flex vertebral column
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Discuss the diaphragm. (Structure, Function/How it works)

A
    • Most important muscle for breathing
  • Dome shaped muscle
  • Separates thoracic and abdominal cavities
  • Muscle fibers insert on fibrous central tendon
  • Diaphragm contracts, central tendon pulls down which increases dimensions of thoracic cage
  • Compresses abdominal cavity which increases abdominal pressure
  • Helps blood return to the heart from the lower extremities
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is a hernia?

A

A portion of the viscera protrudes through a weakened point of the muscular wall of the abdominal cavity.

  • If that portion of the intestine swells and becomes trapped, blood flow to that portion of the intestine may diminish causing that part of the ins tine to die; “Strangulated intestinal hernia”
  • Painful and can be life threatening
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

List and describe the 2 types of hernias.

A
  1. Inguinal hernia
    - most common type
    - more likely in males
    - rising pressure in abdominal cavity pushes segment of small intestine into canal
    - 2 types: direct and indirect
  2. Femoral hernia
    - more likely in females
    - occurs in upper thigh just inferior to inguinal ligament
    - loop of small intestine protrudes through femoral triangle
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

List and describe the 2 types of Inguinal hernias.

A
  1. Direct inguinal hernia
    - small intestine protrudes directly through superficial inguinal ring but not all the way down the inguinal canal
    - creates bulge in lower anterior abdominal wall
  2. Indirect inguinal hernia
    - hernia travels down the entire length of the inguinal canal and may extend into the scrotum
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

List the 5 groups of axial muscles.

A
  1. Muscles of Head/Neck
  2. Muscles of the Vertebral Column
  3. Muscles of Respiration
  4. Muscles of Abdominal Wall
  5. Muscles of the Pelvic Floor
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Muscles of Head/Neck

A

Originate on either the skull or hyoid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Muscles of Facial Expression

A
  • Originate in superficial fascia or on skull bones
  • Insert into superficial fascia of skin
  • Contort skin causing it to move
  • Mouth is most expressive part of face
  • Orbicularis Oris encircles mouth opening and when it contracts, mouth closes
  • most innervated by cranial nerve VII (facial nerve)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Extrinsic Eye Muscles

A
  • “Extraocular muscles”
  • Move the eyes
  • Originate in orbit from common tendinous ring
  • Insert onto sclera
  • 6 muscles: Innervated by either CN III, IV, or VI
    4 rectus muscles: medial, lateral, inferior, superior
    2 oblique muscles: inferior, superior
- Innervations, movement -
Rectus muscles: 
medial (CN III) pulls eye medially
lateral (CN VI) pulls eye laterally
inferior (CN III) pulls eye inferiorly
superior (CN III) pulls eye superiorly

Oblique muscles:
inferior (CN III) elevates and turns eye laterally
superior (CN IV) depresses and turns eye laterally

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Muscles that Move the Tongue

A
  • Manipulate food in mouth to prepare for swallowing
  • Intrinsic and Extrinsic Muscles
  • Intrinsic: curl, squeeze, fold tongue for chewing and speaking
  • Extrinsic: originate on head and neck structures, insert on tongue; aid tongue movement for speech
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Muscles of the Pharynx

A
  • “throat”
  • muscles attach or help form tube
  • primary muscles here are pharyngeal constrictors (superior, middle, inferior)
  • initiate swallowing and force food down into esophagus
  • help elevate palate when swallowing
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Muscles of Anterior Neck

A
  • suprahyoid muscles: superior to hyoid

- infrahyoid muscles: inferior to hyoid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Muscles of Posterior Neck

A
  • extend head/neck

- trapezius attaches to skull and helps extend head/neck but main function is pectoral girdle movement

17
Q

Anterolateral Neck Muscles

A
  • provide head/neck flexion
  • main muscles:
    • sternocleidomastoid
      • also causes lateral flexion & rotation of head
    • scalenes (anterior, middle, posterior)
18
Q

Muscles of the Vertebral Column

A
  • covered by most superficial back muscles
  • 2 major groups:
    1. Erector Spinae (3 muscles)
  • maintain posture
  • extend spine
  • laterally flex spine
  1. Transversospinalis
    - deep to erector spine
    - connect and stabilize vertebra
19
Q

Muscles of Respiration

A
  • located on the anterior and posterior surfaces of thorax
  • covered by superficial muscles
  • via contraction and relaxation of these various muscles, inhalation and exhalation occur (moving air in and out of the lungs)

Muscles invovled:

  • Serratus posterior superior
  • Serratus posterior inferior
  • External intercostals
  • Internal intercostals
  • Transverse thoracis
  • Diaphragm
20
Q

Muscles of the Pelvic Floor

A
  • Pelvic diaphragm: 3 layers of muscles and associated fascia
  • Extend from ischium and pubis across pelvic outlet to sacrum and coccyx
  • Forms pelvic floor and supports pelvic viscera
  • Pelvic floor is composed of layers of muscle that form the urogenital and anal triangles
  • Supports organs in the pelvic cavity
21
Q

Name and briefly describe the 3 erector spine muscles.

A

“Salt Lake International - SLI”

  1. Spinalis
    - most medial to spine
    - cervical and thoracic portions
    - insert onto spinous processes of vertebra
  2. Longissimus
    - capitis, cervical, and thoracic parts
    - between spinals and iliocostalis
  3. Iliocostalis
    - most lateral group
    - cervical, thoracic, and lumbar parts