Practical topic 12 Flashcards
1
Q
Give the muscles of the thoracic girdle (except m. sternocleidomastoideus)
A
Superficial:
- M. trapezius
- M. omotransversarius
- M. latissimus dorsi
- Mm. Pectoralis superficialis
Deep:
- M. pectoralis profundus/ Deep pectoral muscle/M. pectoralis ascendes
- M. rhomboideus
- M. serratus ventralis
2
Q
M. trapezius
A
Origin:
- Between c3-th9 region.
- Pars cervicalis:
- From raphe of neck.
- Pars thoracica:
- From supraspinous ligament.
Insertion:
- Pars cervicalis:
- Proximal 3/4 of spina scapula (distally you can find omotransversius).
- Pars thoracis:
- Proximally third of spina scapula.
Action:
- Supports trunk.
- Elevates (lifts) forelimb.
- Draws forelimb cranially.
3
Q
M. Omotransversarius
A
Origin: Distal part of spina scapula, then runs under m. sternocleidomastoideus.
Insertion: Caudal border of ala atlantis on atlas.
Action:
- If limb is free: draws shoulder cranially.
- If limb is fixed: flexes neck laterally.
4
Q
M. Latissimus dorsi
A
Origin:
- Superficial layer of thoracolumbar fascia.
- From spinous process of last 7-8 thoracic and lumbar vertebrae.
- Proximally to the last few ribs.
Insertion: Tuberositas m. teres major (together with m. Teres major).
Action:
- Draws free limb caudally.
- With teres major: flexes shoulder.
5
Q
M. Pectoralis superficialis
A
Origin:
- M. pectoralis descendens:
- Manubrium sterni
- M. pectoralis transversus:
- From sternebrae 1-3.
Insertion:
- Crista tuberculi majoris
- Upper part of crista humeri.
Action:
- Ventral connection to forelimb.
- Adduction.
- Draws limb cranially or caudally depending its position.
6
Q
M. Pectoralis profundus
A
Origin:
- All sternebrae of sternum.
- Costal cartilages of true ribs.
Insertion:
- Main part inserts on tuberculum minor of humerus.
- A small aponeurosis joins to tuberculum majus.
Action:
- Supports trunk.
- Behaving as a strong retractor (draws limb caudally)
- Adductor of forelimb.
7
Q
M. Rhomboideus
A
Origin:
- Pars capitis:
- Crista nuca of occipital bone.
- Pars cervicis:
- From raphe of neck to spinous process of th1-3.
- Pars thoracis:
- Processus spinosus of th4-7.
Insertion: Dorsomedial border of scapula.
Action:
- Elevates limb
- Pulls base of scapula against trunk forwards or backwards (depending on which part will contract more).
8
Q
M. Serratus ventalis
A
Origin:
- Pars cervicalis:
- Transverse process of cervical 2-7.
- Pars thoracis:
- Middle of rib 1-8.
Insertion: Facies serrata on scapula (medially)
Action:
- Supports trunk
- Helps inspiration
- Carries shoulder cranially or caudally with respect to position of forelimb.