Tension Lines

• keep the skin taut
• lacerations or surgical incisions that parallel lines usually heal with less scarring
• if perpendicular to the lines keloid (excessive) scarring can occur
• stretch marks come from excessive stretching- they can shrink but never disappear

1st degree- limited to superficial part of epidermis

2nd- damage from epidermis to superficial part of dermis

3rd- entire epidermis, dermis, and underlying muscle are damaged, open ulcerated portion requires skin grafting to heal

note- the extent not the degree is more important in estimating the effect on well-being of patient

• unused bones atrophy (decrease in size)
• can be absorbed
• hypertrophy (enlarge) when increased weight to support for long periods of time

• fracture-break
• to heal a fracture the bones must be brought to close to normal position- reduction of fracture
• fibroblasts- connective tissue cells- secrete collagen to form a collar of callus to hold bone together

• Bone degeneration
• reduction of bone quantity or atrophy of skeletal tissue
• bones become brittle, loose elasticity, fracture

• form when additional ossification centers appear and form extra bones
• sutural bones- seen along the sutures of the cranium where the flat bones come together
• common in the foot

1. The appearance of calcified material in the diaphysis and or epiphysis
2. the disappearance of the dark line representing the epiphysial plate

• can be helpful in predicting adult height
• approximate age of human skeletal remains

• when fractured in an adult the same thing will only cause displacement in a child
• a displaced epiphysial plate could be mistaken for a fracture and separation mistaken for a displaced piece of fractured bone

* Fractures leave sharp and often uneven edges of bone

loss of blood supply to an epiphysis or other bone part results in death of bone tissue

after every fracture a small amount of avascular necrosis occurs

• degenerative joint disease
• common in older people and usually affects joints that support body weight
• degenerative changes in joints result in the articular cartilage becoming less effective as a shock absorber and lubricated surface

1. Person performs movements that resist those produced by the examiner (active)
2. The examiner performs movements against resistance prodced by the person

EMG-makes it possible to analyze indiv activity and is used in restoring the action of muscles

1. Examinar places surface electrodes over a muscle and asks the person to perform movements
2. amplifies and records differences baseline activity(tonus) occurs while sleeping

May be caused by:

1. immobilization of a limb
2. primary disorder of the muscle
3. lesion of a motor unit

1. Compensatory hypertrophy- myocardium responds to increasing deman by increase fiber size

ex) when myocardial necrosis occurs and forms a myocardial infarct (MI)

communications

arteries- provide numerous potential detours for blood flow in case the usual pathway is obstructed

• ensures blood supply to structures distal to the blockage
• collateral pathways take time to develop

• hardening of arteries
• atherosclerosis- common form- associated with build up of fat in arterial walls
• atheromatous plaque- formed by calcium deposits cause arterial narowing and irregularity

• abnormally swollen, twisted veins, most often seen in legs
• valve cusps do not meet or have been destroyed by inflammation

1) Lymphangitis and lymphadenitis

2) Lymphedema

1) 2ndary inflammation of the lymphatic vessels and lymph nodes (respectively)

2) the accumulation of inerstitial fluid

• injured axons do not recover in most cases
• proximal stumps begin to regenerate sending sprouts into their area of lesion but growth is blocked by astrocyte proliferation 
• permanent disability follow destruction of CNS

• axons degenerate distal to the lesion
• no surgical repair is necessary ofr a crushing nerve injury
• constricting nerve blood may result in ischemia

• Weakest part of the rib is just anterior to its angle
• middle ribs are commonly fractured

• When sizeable segment of the anterior and/or lateral thoracic wall moves freely because of multiple rib fractures
• extremely painful and impairs ventilation

Increased or decreased by cervical and/or lumbar ribs

Cervical Ribs- can compress spinal nerves C8 and T1

not common

usually has a comminuted fracture- broken in several places

can result due to injury to its motor supply from the phrenic nerve

each half is seperate

instead of descending on inspiration the paralyzed portion is pushed superiorly

and H shaped cut through the perichondrium of one or more costal cartilages and then shelling out segments of costal cartilage to gain entrance to the thoracic cavity

* posteriolateral aspects of 5th and 7th for posterior thoracotomy

slipping rib syndrome

displacement of the of a costal cartilage from the sternum

rib separation- dislocation of a costochondral jnct

creamy white to yellowinsh premilk fluid, may secrete from the nipple during the last trimester and initial nursing episodes

rich in protein, immune agents, and a growth factor

supernumerary breasts

may occur along a line from the axilla to the groin, along the mammary crest

inflammation of the pleurae

the resulting friction may be heard

-tapping the chest over the lungs with the finger

airfilled- resonant

fluid filled- dull sounds

solid- flat sound

-visceral- insensitive to pain because its innervation is autonomic

-parietal- sensitive to pain because supplied by branches of the somatic intercostal and phrenic nerves

-pain is referred and local

inflammation of the pericardium

makes the surface rough and the resulting friction

the density and size of the heart

performed at the 3,4,5 intercostal spaces