Vol.4-Ch.9 "Orthopedic Trauma" Flashcards
(44 cards)
What % of bone tissue is replaced each year?
20%
Haversian Canals Vs Perforating Canals?
Haversian Canals are small tubes in bones that allow for small blood vessels to travel within the bone
Perforating Canals allow for blood vessels to enter and exit the bones, allowing for exchange and flow of blood and tissues
Osteocytes VS Osteoblasts/Osteoclasts
Osteocytes are bone cells trapped in a matrix in the bones and help regulate collagen, calcium, phostphate, carbonate, and other crystals.
Osteoblasts lay down new bones in areas where stress and growth call for more tissues
Osteoclasts break down bone in areas that don’t need as much bone tissue for support and also to break down for release of calcium when the body needs a surplus
Diaphysis VS Epiphysis VS Metaphysis
Diaphysis is the middle, long shaft of the bone and is structurally strong with a very dense layer and a thin layer to make it lighter
Epiphysis is the end of the bones and is wider and spongy b/c it is Cancellous bone (spongy bone)
Metaphysis is in between the other two, a small section just above the epiphysis; It also houses the EPIPHYSEAL PLATE or growth plate where during childhood, cartilage is generated here and the plate widens. (injury to this in childhood will stunt growth)
What causes bone growth in children?
It occurs when the osteoblasts in the diaphysis deposit salts into the forming cartilage’s collagen matrix in the metaphysis’ EPIPHYSEAL PLATE to create new bone
Where are yellow and red bone marrow stored in bones?
YBM: is stored in semiliquid form fat and is in the central medullary canal, which is the hollow portion of the diaphysis and cancellous bone of the epiphysis
RBM: is in the cancellous bone chambers of the larger long bones, pelvis, and sternum. (it is responsible for manufacturing erythrocytes and other blood cells)
What is the periosteum?
It is the tough fibrous membrane on the outer surface of the diaphysis; is is very vascular and has a lot of nerves that send pain signals and initiate the bone repair cycle. It is also what the tendons attach to
What is cartilage made of?
Collagen
How are bones classified?
By their general shape
Long, short, flat, irregular
carpals and tarsals are only short bones; vertebra and face bones are only irregular
What are the 3 general types of joints (based on amount of movement allowed)
1) Synarthroses (no movement; skull sutures, teeth/jaw juncture)
2) Amphiarthroses (limited movement; vertebrae, sacrum/ilium/pelvis)
3) Diarthroses (relatively free movement; typical joints)
What are the 3 categories of Diarthroses joints?
1) Monoaxial Joints (hinge; knee, elbow, finger & Pivot; axis or atlas that have 180 degree rotation)
2) Biaxial Joints (Condyloid or gliding, ellipsoidal, saddle)
3) Triaxial Joints (ball and socket)
What forms a joint capsule?
A joint capsule is formed when Ligaments surround a joint (knee for ex), within the capsule is SYNOVIAL FLUID, which reduces friction and circulates O2, nutrients, and waste. CARTILAGE acts like a sponge that pushes out synovial fluid when compressed and soaks it up when relaxed. There are BURSAE which are sacs filled with synovial fluid the help absorb shock
Tendon VS Ligament?
Tendon = bone to muscle Ligament = bone to bone
7 types of muscle injury:
1) CONTUSION - damages muscle cells and blood vessels, blood leaking into interstitial space and across muscle will cause inflammatory response; swelling of injured limb may be noted. In severe cases on large muscles, a hematoma may be caused big enough to contribute to hypovolemia
2) COMPARTMENT SYNDROME - when muscle injury causes swelling within the inelastic fascial envelopes called compartments this will reduce capillary blood flow which causes a histamine release at location, increasing permeability and worsening swelling. End result is compression of nerves and capillaries at muscle and PAIN DISPROPORTIONATE TO APPEARANCE OF INJURY. Distal pulse and cap refill may be normal b/c it takes much more pressure to shut these flows off, numbness from nerve compression may be present
3) PENETRATING INJURY
4) FATIGUE - occurs when muscles reach their performance limits by using its O2 and energy reserves causing a build up of metabolic biproducts that cause hypoxia, acidic, toxic, and energy deprived state only relieved by oxygen flow restoration
5) CRAMPS - not an injury but a painful muscle spasm or contraction. Can be helped by repositioning or massaging. Can be caused by electrolyte imbalance like hypocalcemia or lactic acid accumulation
6) SPAMS - An intermittent (clonic) or continuous (tonic) contraction of the muscle, usually subsides with rest
7) STRAIN - occurs when the muscle fibers are overstretched and damaged
What are the 3 types of joint injuries?
1) Sprain - tearing of of a joint capsule’s connective tissue (ligament(s)); pain is immediate and swelling follows soon after. Put into 3 grades (on another card)
2) Subluxation - a PARTIAL bone end displacement from its position within a joint capsule, this may tear or just severely stretch ligaments. It reduces joint integrity MORE than a sprain but may present with similar symptoms
3) Dislocation - a COMPLETE bone end displacement, where the joint fixes in an abnormal position with obvious deformity, this carries obvious joint capsule and ligament damage but can also damage nerves and blood vessels
What are the 3 grades of a joint sprain?
Grade I: Minor and incomplete tear; joint stable with minor swelling
Grade II: Significant but incomplete tear; swelling and pain can be severe, joint is intact but unstable
Grade III: Complete ligament tear, may even present as fracture due to severe pain and spasm, joint is unstable
What is parasthesia?
paresis?
anesthesia
paralysis
Pins-and-needles feeling
weakness
loss of sensation
loss of muscle control
What are the 9 types of fractures?
1) hairline - small crack but doesn’t disrupt the total structure
2) Impacted - when bone is compressed on itself, fracture is there but the bone remains in place
3) Transverse - transverse is fractured like impacted where it runs 90 degree but the ends are now displaced
4) Oblique - similar to transverse but the fracture is at a 45 degree angle and displaced
5) Comminuted - fracture that has splintered into several smaller fragments
6) Spiral - occurs when a limb is twisted causing a curved break
7) Fatigued - (stress fracture) occurs due to repeated stress
8) Greenstick - commonly only in kids b/c of their higher percentage of cartilage and bone flexibility. It is when a bone bends and fractures partially on one side; due to the stiffness of the periosteum it won’t want to bend back but will still undergo a healing process which leaves the injured side to be more built up and permanently bowed. Surgeons will often complete the fracture in order to assure equal healing (similar to a buckle or torus fracture)
9) Epiphyseal - fracture in the epiphyseal plate in children, due to the increased size of it during bone growth (most common in the proximal tibia)
What is a rare but serious complication that can occur with a severe bone fracture, usually comminuted frequently caused by crush injuries?
The release of the semiliquid fat (yellow bone marrow) that may find it’s way into a ruptured vein, which would travel through to the lungs and become a pulmonary embolism
According to the Salter-Harris system of classifying growth-plate injuries, what are the 5 types?
Type I: fracture transversing the growth plate, not affecting bone above or below
Type II: fracture involving the growth plate and the bone above (diaphysis)
Type III: fracture involving the growth plate and the bone below (epiphysis)
Type IV: fracture involving the growth plate and the bone above and below
Type V: is a crushing type injury involving the entire distal bone
Describe the bone healing process in 4 steps:
1) Bone injury occurs disrupting the periosteum and local blood vessels/nerves. These vessels bleed into the fracture and the blood clots. The blood clot mixes with collagen to form a fracture hematoma that stops hemorrhaging and weakly immobilizes the fracture
2) Cartilage forming cells migrate into the hematoma from the broken bone ends and begin to repair, forming a more significant mass to stabilize the joint. This mass becomes a Callus
3) Osteoblasts then move into the callus to begin laying down new bone cells to bring the fracture back to bone strength. The callus will eventually be bigger than needed however.
4) Once the callus is done and formed, osteoclasts and osteoblasts will begin laying down or breaking down bone cells in order to “form” the bone back to its needed and possibly original size
What are the 6 Ps in evaluating a Limb Injury?
- pain
- pallor
- paralysis
- paresthesia
- pressure
- pulses
(sometimes poikilothermia or cool to the touch)
What are the 4 categories of musculoskeletal pts?
- Life and limb threatening injury
- life threatening injury , minor musculoskeletal injury
- non life threatening injury, minor musculoskeletal injury
- non life threatening, isolated minor musculoskeletal injury
What are 6 early signs of compartment syndrome?
- feeling of tension in limb
- loss of distal sensation (especially in webs of hands and feet)
- complaints of pain
- condition more severe than mechanism of injury would suggest
- pain on passive extension of extremity
- pulse deficit (late sign)
