Block 2: Back and Thorax

What are the primary curvatures of the spine?

The thoracic and sacral curves.

What are the secondary curvatures of the spine?

The cervical and lumbar curves.

How many vertebrae are in the cervical curvature?

7 vertebrae.

At what age does the cervical curvature develop?

Around 3 to 4 months of age.

At what age does the lumbar curvature develop?

Around 12 to 18 months of age.

What is scoliosis?

A lateral curvature of the spine that can cause various health issues.

What is kyphosis?

An exaggerated anterior-posterior curvature of the spine, typically in the thoracic region.

What is lordosis?

An excessive curvature of the lumbar spine.

What are the contents of the vertebral foramen?

spinal cord, menignges, fat, vessels, CSF, spinal nerve roots

What are the contents of the intervertebral foramen?

spinal nerve, dorsal root ganglion, vessels

What are the contents of the transverse foramen of the cervical vertebrae?

Vertebral arteries and veins.

What is the clinical significance of a Hangman Fracture?

It is a fracture of the C2 vertebra, arch of axis pushes the dens posteriorly and compresses brain stem

What is the function of the intervertebral disc?

To absorb shock and provide flexibility to the spine.

What does it mean for a disc to herniate?

The inner gel-like nucleus of the disc bulges out, which can compress nearby nerves, mostly posterolaterally where annulus fibrosus is thinner

What is the most common site of herniation?

The lumbar region, particularly L4-L5 or L5-S1 levels.

What is the function of the trapezius muscle?

To move and stabilize the scapula, and extend the neck.

What is the location of the trapezius muscle

either side of upper back

Where is the latissimus dorsi located?

It extends from the lower back to the upper arm. (coughing muscle)

What is the function of the levator scapula muscle?

To elevate the scapula.

What are the functions of the rhomboid major and minor?

To retract and elevate the scapula.

What are the muscles included in the erector spinae?

Iliocostalis, longissimus, and spinalis.

What are the boundaries and contents of the suboccipital triangle?

Bounded by the rectus capitis posterior major, obliquus capitis superior, and obliquus capitis inferior; contains the vertebral artery and suboccipital nerve.

At what level of the vertebral column does the spinal cord end?

Typically around L1-L2 level.

Why is the spinal cord ending level relevant for a lumbar puncture?

To avoid damaging the spinal cord, the puncture is performed below this level.

Where is the site for epidural anesthesia?

In the epidural space, typically in the lumbar region., given at sacral hiatus point

What is the clinical significance of spina bifida?

A birth defect where the spine does not close completely, potentially leading to neurological issues.

What is the Clinical significance of spina bifida

folic acid substitution in conception and during pregnancy decreases the risk of spina bifida.

What is the Clinical significance of spina occulta

closed asymptomatic NTD in which some of the vertebrae are not completely closed.

What is Meningocele

Perfusion of the meninges through a defect in the skull or spine

What is Myelomeningocele

Open spinal cord (w/ a meningeal cyst)

What is the clinical significance of fractures in the 1st rib cage?

rarely happens. huge danger to vessels such as the subclavian artery. fracture to this rib and the clavicle leads to incompatibility with life

What is the clinical significance of fractures in the middle rib cage?

Most commonly fractured

What is the clinical significance of fractures in the lower rib cage?

May damage the pleura and abdominal viscera(kidney,liver,spleen)

What are the parts of the sternum?

Manubrium, body, and xiphoid process.

Which structures do ribs articulate with?

The body and transverse process of the thoracic vertebrae.

Which muscles elevate the thoracic cage?

scalene muscles (posterior, anterior, and middle), pectoralis major/minor, sternocleidomastoid

Where are the intercostal vessels and nerves located?

Between the internal and innermost intercostal muscles.

Clinical significance of intercostal vessels and nerves located?

coarctation of aorta:all theses arteries are dilated (eben braches off the subclavian artery)

thoracentesis: produce performed due to the increase of fluid in thoracic, involves using a needle to extract fluid\

What is the clinical significance of the internal structures of the breast?

They are important for breast health and potential cancer detection.

The breast is composed of how many lobules

15-20 glandular tissue (mammary gland); each lobule is drained by a lactiferous duct which opens into the nipple

What happens to the breast during puberty?

the lactiferous ducts undergo branching; an increase in fat deposition leads to breast enlargement

What is the retromammary space

between the breast and deep fascia, a tumor here may contract the pectoralis major

What is the importance of the suspensory ligaments

extend from the skin to deep fascia and support the breast; their invasion by tumor may cause dimpling of skin PROVIDES SUPPORT FOR BREAST

Which hormones are responsible for breast growth?

Estrogen

What does estrogen do?

growth of tubular system which is the lactiferous ducts, estrogen coming from ovaries helps develop the tubular system

What does progesterone do?

development of milk secreting lobules which is seen durong post ovulation and pregnant women

What is the clinical significance of breast cancer?

A leading cause of cancer-related death in women.

How can breast cancer be indicated?

be indicated by what is called orange peel: this is dimpling (invagination) thickening of the skin especially if the lymphatic system is blocked

What is mastectomy?

is the removal of breast the long thoracic nerve (holds scapula in place) could be in danger which results in "winged scapula"

What is lumpectomy?

most of the time if the cancer lump is removed via this. specimen sent off to pathology in order to determine if margins are clear in order to make sure they got all of the cancer, whereas a biopsy (needle biopsy) is different.

What is gynecomastia (Klinefelter syndrome)?

XXY; most common congenital cause of infertility in males

What is the clinical significance of a Tension pneumothorax?

air enters the pleural cavity but not leaving it

Tension pneumothorax?

mediastinal shift: the mediastinum is shifted toward the normal side, increased intrathoracic pressures

What is the clinical significance of a sucking pneumothorax?

air enters and leaves the pleural cavity

sucking pneumothorax?

mediastinal flutter (mediastinum shifted toward the normal side in inspiration and to the injured side in expiration)

What are the types of pleural effusion?

Hydrothorax, pyothorax, chylothorax, and hemothorax.

Hydrothorax

congestive heart failure

pyothorax

infection pus

chylothorax

injury to thoracic duct

What is the clinical significance of pleuritis?

Inflammation of the pleura can lead to pain and breathing issues.

What are the tracheal divisions?

The primary bronchi, secondary bronchi, and tertiary bronchi.

What is thoracocentesis(pleural tap)?

a procedure to drain pleural fluid in pathological conditions, performed posterior to the midaxillary line while patient is seated

What is the process of gas exchange within the lung?

Occurs at the alveolar-capillary membrane, where oxygen and carbon dioxide are exchanged.

What is the pulmonary circulation pathway?

Right Atrium → Right Ventricle via Tricuspid Valve

Right Ventricle → Pulmonary Trunk via Pulmonary Semilunar Valve

Left Atrium → Left Ventricle via Bicuspid (Mitral) Valve

Left Ventricle → Aorta via Aortic Semilunar Valve

What are the layers of the pericardium?

fibrous and serous

Layers of teh heart?

fibrous, parietal, visceral/epicardium, myocardium, and endocardium

What is the serous pericardium made up of?

parietal + visceral/epicardium

What is the clinical significance of pericarditis?

Can lead to chest pain and complications such as cardiac tamponade.

What is cardiac tamponade?

occurs when you have a heart attack and is quite severe bc it was built up, coming up for awhile bc there is blocked coronary arteries, death of cardiac cells, so when it happens the heart wall splits, so blood is coming from inside one of the chambers and out

What are the branches of the left coronary artery?

anterior interventricular artery, circumflex branch, left marginal artery

What does anterior interventricular artery supply?

supplies both ventricles and interventricular septum

What does circumflex branch supply?

supplies the left atrium, left surface of the heart, and let ventricle

What does left marginal artery supply?

a branch of circumflex artery, supplies left ventricle

What does right coronary artery supply?

right atrium

What does right marginal artery supply?

both ventricles

What does posterior interventricular artery supply?

both ventricles and posterior part of interventricular septum

The main cardiac vein drains into?

Coronary Sinus

What makes the main cardiac veins?

great cardiac vein, middle cardiac vein, and small cardiac vein

Where does great cardiac vein lay?

lies in the anterior interventricular groove

Where does middle cardiac vein lay?

lies in the posterior interventricular groove

Where does small cardiac vein lay?

lies in right coronary groove (2 and 3 drain most of the right coronary artery blood)

Where does posterior vein of the left ventricle lay?

on inferior and posterior surface

The anterior cardiac veins (several on the right ventricle) usually enters?

the right atrium

The smallest cardiac veins (thesbesian veins) begin?

in the myocardium and open directly into heart chambers, mainly atria; also carry blood to the myocardium

R Superficial Temporal V + R Facial V →

R Internal Juglar V

L Superficial Temporal V + L Facial V →

L Internal Juglar V

R Subclavian V+ R Internal Juglar V →

R Brachiocephalic V

L Subclavian V+ L Internal Juglar V →

L Brachiocephalic V

R Brachiocephalic V →

SVC

L Brachiocephalic V →

SVC

SVC →

R Atrium

Left Ventricle →

Ascending Arota

Arch of Arota →

Brachiocephalic Trunk

Arch of Arota →

L Commomn Carotid A

L Common Carotid a →

L External Carotid a

L Common Carotid a →

L Internal Carotid a

L External Carotid a →

L Facial a

L External Carotid a →

L Superficial Temporal a

Arch of Arota →

L Subclavian A