week 8 sem 2 Flashcards
Bones of the thorax
- 12 paired ribs (plus costal cartilages)
- 12 thoracic vertebrae
- Sternum
Ribs
1-7: true ribs
* attach directly to the
sternum via their own
costal cartilage
* 8-10: false ribs
* attach indirectly to the
sternum via the costal
cartilage of the rib above
* 11-12: floating ribs
* do not attach to the
sternum
what are the 3 parts of the sternum
- Manubrium
- Body
- Xiphoid process
Thoracic inlet (superior thoracic aperture) boarder
Anterior: manubrium of
sternum
* Lateral: 1st ribs and costal
cartilages
* Posterior: T1 vertebra
Thoracic outlet (inferior thoracic aperture) boarders
- Anterior: xiphisternal joint
and costal margin - Lateral: floating ribs
- Posterior: T12 vertebra
- Closed off by the (thoracic)
diaphragm
- Manubriosternal joint classification
- Between manubrium and body of
sternum - Classification: secondary
cartilaginous (symphysis) - Slightly movable
- Xiphisternal joint
- Between xiphoid process and body of
sternum - Classification: secondary
cartilaginous (symphysis) - Slightly movable (but ossifies in
middle age)
- 1st sternocostal joint
Classification: primary cartilaginous
(synchondrosis)
* Immovable
- Costochondral joints
Between ribs and their costal cartilages
* Classification: primary cartilaginous
(synchondrosis)
* Immovable
- 2nd-7th sternocostal joints
- Classification: synovial, multiaxial,
plane - Small gliding movements
- Interchondral joints
Between costal cartilages of ribs 6-10
* Classification:
* 6-7, 7-8 and 8-9: synovial, multiaxial,
plane
* 9-10: fibrous
Costovertebral joints
- Classification: synovial, multiaxial,
plane - Articular surfaces:
- Heads of ribs
- Bodies of thoracic vertebrae
- Movements: small gliding
movements
Costotransverse joints
- Classification: synovial, multiaxial,
plane - Articular surfaces:
- Tubercles of ribs (articular part)
- Transverse processes of
thoracic vertebrae - Movements: small gliding
movements
Costovertebral joints ligamnets
- Radiate ligament
- Intra-articular ligament
- Costotransverse joints ligaments
- Superior costotransverse ligament
- Lateral costotransverse ligament
- Costotransverse ligament
- Radiate ligament
From head of rib to body of
corresponding vertebra, body of
vertebra above and intervening
IVD
* Reinforces joint capsule
- Intra-articular ligament
From head of rib (crest between
two articular facets) to IVD
* Divides the joint cavity into two
- Superior costotransverse ligament
- From neck of rib to transverse
process of vertebra above
- Lateral costotransverse ligament
- From tubercle of rib (non-articular
part) to tip of transverse process
of corresponding vertebra
- Costotransverse ligament
- From back of neck of rib to
front of transverse process of
corresponding vertebra
- Anterior abdominal wall muscles
Rectus abdominis
* External oblique
* Internal oblique
* Transversus abdominis
* Pyramidalis
- Posterior abdominal wall
Quadratus lumborum
* Psoas major
* Psoas minor
* (Iliacus)
Rectus abdominis – rectus sheath
- Formed by the aponeuroses of
external oblique, internal oblique and
transversus abdominis - (i) From costal margin to midpoint
between umbilicus and pubic
symphysis – anterior and
posterior layers - (ii) Below midpoint between
umbilicus and pubic symphysis –
anterior layer only
- Movers produce trunk, neck and head movements
Erector spinae
* Semispinalis
* Multifidus (although more important for
stability)
Stabilisers provide intersegmental stability to the
trunk during movement
Multifidus
* Rotatores
* Interspinales
* Intertransversarii
Functional roles of deep back muscles
- Deep back muscles provide proprioceptive
feedback - Rotatores
- Interspinales
- Intertransversarii
- Deep back muscles protect the zygapophyseal
joints - Multifidus
- Medial branch innervates
- Spinalis
- Transversospinalis group
- Unisegmental group
- Zygapophyseal joints
(via two dorsal rami)
- Lateral branch
- Longissimus
- Iliocostalis
