Lecture 4: Back Myology Flashcards
What is an aponeurosis?
White fibrous tissue that takes place of a tendon in flat muscles having a wide area of attachment
What are pennate muscles?
Defines where muscles are
Unipennate: Muscles are one side of tendon
Bipennate: Muscles on both sides
Multipennate: Muscles all over the place
What does “fusiform” mean?
Muscles are big in the middle, small on the ends
What are digastric muscles?
2 muscle bellies connected by tendon
What are multiventral muscles?
Muscles with tendinous inscriptions?
Example: Rectus Abdominis
What makes multicaudal muscles unique?
Multiple tendons (looks like tails)
Common in extremities (fingers and toes)
Where do serrated muscles attach?
The ribs.
Functionally, what do Agonists do?
Flex a joint
Functionally, what do Antagonists do?
Extend a joint
What do Synergist muscles do?
Assists the agonists
What is the action of the trapezius muscle?
Whole Muscle: Retracts the scapula and Rotates glenoid cavity superiorly
Superior Part: elevate scapula
Inferior Part: depress scapula
Scapula fixed: Extend neck (bilaterally), Laterally flex neck and rotate face away (unilaterally)
What is the innervation and blood supply for the trapezius muscle?
Innervation: Spinal Accessory Nerve (CN XI)
Blood Supply: Transverse Cervical Artery
What is the action of the latissimus dorsi?
Extends and adduct humerus
Medially rotate humerus
Rotate glenoid cavity inferiorly
What is the innervation and blood supply for Latissimus Dorsi?
Innervation: Thoracodorsal Nerve
Blood Supply: Thoracodorsal Artery
What is the action of the rhomboid major and minor?
Retract scapula
Elevate scapula
Rotate glenoid cavity inferiorly
What is the action of levator scapulae?
Retract scapula
Elevate Scaupla
Rotate glenoid cavity inferiorly
With Scapula Fixed:
Extend neck bilaterally
Laterally flex neck unilaterally
What is the innervation and blood supply for Rhomboid Minor, Rhomboid Major and Levator Scaupluae?
Innervation: Dorsal Scapular Nerve
Blood Supply: Dorsal Scapular Artery
What is the action of the Serratus Posterior Superior muscle?
Elevates rib (for inspiration)
Proprioception
What is the innervation and blood supply for Serratus Posterior Superior?
Innervation: Intercostal Nerve
Blood Supply: Posterior Intercostal Artery
What is the action of Serratus Posterior Inferior muscle?
Depresses rib (for expiration)
Proprioception
What is the innervation and blood supply for Serratus Posterior Inferior muscle?
Innervation: Anterior Ramus of T9-12
Blood Supply: Posterior Intercostal Arteries
What is the action of Splenius Capitis and Splenius Cervicis?
Extends neck bilaterally
Laterally flexes the neck unilaterally
Rotates the face towards the muscle unilateraly
What is the innervation and blood supply of Splenius Capitis and Cervicis?
Innervation: Posterior Rami
Blood Supply: Deep Cervical Artery
In general, what is the action of the erector spinae muscles?
Maintain erect posture
Extend and laterally flex vertebral column and neck
What is the innervation and blood supply of erector spinae muscles?
Innervation: Posterior rami
Blood Supply: Deep Cervical Artery/Intercostal artery
What are the three segments of Iliocostalis Muscle?
Iliocostalis Lumborum (only Lumborum)
Iliocostalis Thoracis
Iliocostalis Cervicis
What are the three segments for Longissimus?
Longissimus Thoracis (largest)
Longissimus Cervicis
Longissimus Capitis (Inserts at the Mastoid process, to help locate it)
What are the three segments for Spinalis?
Spinalis Thoracis (Often confusible with Longissimus because it is small)
Spinalis Cervicis (Can’t see)
Spinalis Capitis (Can’t see)
What is damaged in a back strain?
What is damaged in a back sprain?
A strain is damage to a muscle fiber by excessive stretching of a muscle due to contraction. (think tendon)
A sprain is injury to the ligamentous attachment between bones. (think ligament)
Remember that a sprained ankle has nothing to do with muscles.
What are the four types of Transversospinalis muscles?
How far (in number of vertebrae) does each one go up?
Semispinalis (5-6)
Multifidus (3-4)
Rotatores Longus (2)
Rotatores Brevis (1)
What are the three Semispinalis muscles?
Semispinalis Thoracis
Semispinalis Cervicis (ends right below suboccipital triangle)
Semispinalis Capitis (on top of cervicis)
What muscles traverse between spinous processes?
Interspinalis Muscles
What muscles traverse between transverse processes?
Intertransversarii Muscles
What is the innervation and blood supply of the suboccipital muscles?
Innervation: Suboccipital Nerve
Blood Supply: Occipital Artery
What are the four muscles of the Suboccipital region?
Rectus Capitis Posterior Major
Rectus Capitis Posterior Minor
Obliquus Capitis Superior
Obliquus Capitis Inferior
Which three muscles make up the Suboccipital Triangle?
Rectus Capitis Posterior Major
Obliquus Capitis Inferior
Obliquus Capitis Superior
What nerve and artery is found in the suboccipital triangle?
Suboccipital nerve
Vertebral artery
