MSK 1 - General Principles Flashcards
what are the 2 types of bone?
cortical and cancellous
what bone is the “hard” outer surface?
cortical bone
what does the cortical bone support? what is it the site of attachment for?
provides skeletal support and is site of attachment for tendons and ligaments
what is the “spongy”/trabecular bone?
cancellous bone
where is cancellous bone found?
at ends of long bones, pelvis, ribs, skull, and vertebrae
what does the cancellous bone contain?
red/yellow bone marrow
cortical bone is also known as what type of bone?
compact bone
what change does cortical bone and cancellous bone undergo?
both undergo continuous change d/t biochemical and mechanical forces
which type of bone contains bone marrow?
cancellous bone
what does red bone marrow produce? at 30 y/o, where is it mostly?
produces precursors of RBCs
at 30 y/o mostly in axial skeleton
what does yellow bone marrow contain? at 30 y/o, where is it mostly?
contains fat
at 30 y/o mostly in appendicular skeleton
what are the 3 parts of bone?
metaphysics, diaphysis, epiphysis
what is the shaft of the bone?
diaphysis
what part of bone contains the growth plate?
epiphysis
what part of the bone is the transition zone?
metaphysis
what are tendons and what do they attach?
fibrous cords of tissue that attach muscles to bone
what are ligaments and what do they attach?
fibrous cords of tissue that attach bone to another bone
what are the 3 most common MSK conditions reported each year?
trauma, back pain, arthritis
what is key to MSK clinical presentation?
history
acute MSK injury?
< 6 weeks
chronic MSK injury?
> 6 weeks
what is an example of atraumatic MSK injury?
degenerative (ex: arthritis)
overuse syndrome
examples of acute MSK injuries?
fractures, dislocations, ligament strains/sprains, septic joints
examples of chronic MSK injuries?
overuse syndromes, tendonitis, osteoarthritis, osteomyelitis
what is valgus?
get hit from side and knee goes medial -> knock-kneed
what is varus?
knee goes lateral -> bow legged
what is indirect force?
force impacts one end of a limb and damage transmitted to a distant point
physical exam for MSK injuries?
deformity, swelling, painful/decreased ROM (active vs passive), pain with palpation, neuromuscular status
what are the 3 special tests to assess joints?
Provocative tests, stress tests, functional testing
what is provocative testing for assessing joints?
recreate mechanism of injury to reproduce patient’s pain
ex: Lochman’s
what is stress testing for assessing joints?
apply load to test ligament stability
what is functional testing for assessing joints?
useful to assess injury severity and ADLs
what is the definition of a fracture?
loss of continuity of structure of bone
-cortical integrity is interrupted
what can happen to the vessels throughout the bone with a fracture?
they may get torn/ruptured and bleed
definition of a closed fracture
fracture not exposed to environment
all fracture have some degree of what type of injury?
soft tissue injury - don’t underestimate it as it affects tx and outcome
open fracture leads to?
communication of environment with fracture
degree of open fracture based on?
length/size of wound
when is surgical tx recommended for tx of open fractures?
within 6 hours
what is a comminuted fracture?
fracture has >2 pieces
injury variables with fractures?
Location, Severity, Energy of Injury, Morphology of the fracture, Bone loss, Blood Supply, Other injuries
what is the goal of fracture immobilization?
Maintain anatomic position
Principles of Fracture Immobilization
Maintain anatomic position
Prevent movement of fracture
Protect from further injury
Limit neuro injuries (bones have nerves)
Pain control
what is the first method of fracture immobilization?
Splinting
Methods of fracture immobilization
Splinting (first method)
Casting
Closed Reduction Percutaneous Pinning (CRPP)
Open Reducing Internal Fixation (ORIF)
External Fixator (“Ex-Fix”)
Intramedullary (IM) Rodding
what do you worry about with casting a fracture?
compartment syndrome d/t swelling - reason why you don’t put on cast right away
how many days in splinting used for? is it permanent or temporary?
used for 1-5 days
usually temporary until follow-up
Principles of splinting?
immobilize affected extremity/area
prevent further injury
pain control
2 types of splint types?
orthoglass, plaster
for splinting, what joint must you immobilize?
must immobilize joint above/below the injury
what does immobilizing joint above/below the injury, minimizes what?
movement which decreases pain
additional soft tissue injury
risk of closed fracture becoming open
blood loss
when applying splint that wraps an extremity, where do you wrap from? what does this technique do?
wrap from distal to proximal
-minimizes trapping of blood distal to the injury
what do you evaluate before and after splinting?
evaluate distal circulation, motor function, and sensation
when do you evaluate distal circulation, motor function, and sensation with splinting?
before and after splinting
cast is for what type of fracture?
ONLY stable fractures!!!
what does casting do?
maintains position to provide for bone healing
prevents displacement of fracture
protects from further injury
how long is a cast usually on?
4-6 weeks
when is a cast changed?
at 3 weeks if no movement of fracture
for what fractures do you use a short arm cast (SAC)?
wrist fracture
for what fractures do you use a long arm cast (LAC)?
forearm fracture, unstable wrist fracture
what does a long arm cast prevent?
prevents supination/pronation
for what fractures do you use a thumb spica cast?
scaphoid fracture, radial styloid fracture
don’t want thumb moving
what is a better option for casting lower extremities than casting?
splints/walking boots
casting lower extremities used more in who?
children to protect from themselves
what is closed reduction of a fracture? what do you recreate in it?
reduces bone to near anatomic position
recreate the fracture to align
what type of fracture must it be to do closed reduction?
must be a stable fracture for closed reduction
what is very important to have when doing closed reduction of fracture?
sedation/pain control
what does closed reduction percutaneous pinning do for fracture?
reduce/hold unstable closed fracture if casting not able
benefits of closed reduction percutaneous pinning of fracture?
holds unstable fracture (don’t need a plate)
reduces need for ORIF
risks of closed reduction percutaneous pinning of fracture?
skin infection around pins, nerve/vessel injury
differences between CRPP and ORIF?
CRPP has no incisions with skin, skin is intact
-just put pins in
ORIF you make an incision thru skin
what does open reduction internal fixation (ORIF) do?
reduces and holds unstable fractures - open or closed
ORIF acts as?
internal splint
what do ORIF plates/screws do?
allow for anatomic reduction of fracture
provide internal, non-moving repair of unstable fracture
what is a definitive fracture fixation?
ORIF plates/screws
need how many cortices above and below the fracture?
6
what do intramedullary rods do?
prevents anterior/posterior movement of bone
what do intramedullary locking screws do?
prevent bone from rotating around rod
use iron rods for what fractures? why?
femurs and tibial fractures b/c they are LOAD SHARING DEVICES - can put weight on them
when do you use an external fixator for a fracture?
when major non-lifesaving procedures must be avoided
external fixator for a fracture is a bridge to what?
to definitive internal fixation
how long does it take most patients to heal from a fracture?
6 weeks
what are the 3 stages of fracture healing?
- Inflammatory phase (hematoma and granulation tissue)
- Reparative phase (fibrocartilaginous callus formation)
- Bone remodeling
what forms in the inflammatory phase of fracture healing?
hematoma and granulation tissue
hematoma = bleeding as stopped
when does blood clot form at fracture site?
within 8 hours
what removes necrotic tissue at fracture site in inflammatory phase?
phagocytes (neutrophils and macrophages) and osteoclasts
how long does inflammatory phase last?
2 weeks
what forms in the reparative phase of fracture healing?
fibrocartilaginous callus
how is fibrocartilaginous callous formed in reparative phase of fracture healing?
fibrovascular tissue invades hematoma
fibroblasts develop into chondroblasts and produce fibrocartilage -> results in fibrocartilaginous “callus”
how long does callus in reparative phase of fracture healing last?
3-4 months
what happens in the bone remodeling stage of fracture healing?
compact bone replaces spongy bone around fracture periphery
remaining dead fracture portions reabsorbed osteoclasts
most important fracture healing-systemic factors?
Presence of underlying disease (DM and uncontrolled HTN)***
Smoking - don’t get blood flow b/c vasoconstrictor
what is a sprain?
stretching/tearing of ligaments
sprain mechanism of injury?
inversion or eversion
what is the MOST COMMON site of a sprain? how?
ankle - inversion with plantar flexion (M/C)
what is a strain?
injury to muscle or muscle and tendon
muscle fibers tear
what is a strain caused by?
overextension or over stretching
what’s the pain like in a strain?
pain typical to that experienced from muscle overuse
strain sx’s?
pain - worse with use
muscle spasm/weakness
swelling, cramping
sprain/strain tx?
RICE
splinting, NSAIDs, early ROM, physical therapy
what does RICE stand for?
Rest, Ice, Compression, Elevation
how long do you Ice for?
30 min at a time; not just for first 48 hours
elevate above ___
heart level
typical appearance of dislocation?
joint found in abnormal appearance with deformity and possible swelling
pain and tenderness present
can’t move extremity
loss of distal pulses increases the severity of the injury (need to reduce ASAP)
evaluate ____ before AND after reduction of dislocation
neuromuscular status
reason to reduce dislocation ASAP?
b/c can have loss of distal pulses
tx for dislocation
evaluate NV status before and after reduction
antispamotics - Valium; analgesia
REDUCE
splint for pain relief
gentle ROM
follow-up
where does tendinitis cause pain and tenderness?
at or just outside joint
tendinitis is most common where?
shoulders, elbows (ex: tennis elbow), wrists, knees
tennis elbow is tendinitis of what?
lateral epicondylitis - extensors
medial epicondylitis is?
inflammation of the flexors
tx tendinitis?
rest, ice cube massage, brace, NSAIDs, PT, Cortisone (can be done later)
contributing conditions of tendon rupture?
injection of steroids into tendon
use of fluoroquinolone abx
4 most common sites of tendon rupture?
achilles’, biceps (proximal > distal), rotator cuff, quad
ligament rupture is a common injury with what?
sport injury
ligament rupture results from?
valgus stress or direct fall onto joint
ex: valgus stress, stresses the MCL
ACL rupture occurs more common in who?
young athletic women
what is the first-line pharmacologic therapy for arthritis?
Acetaminophen (also preferred for older people b/c of renal fxn)
how much of acetaminophen and how often is it given?
325-650 mg q 4-6hrs
max dose of APAP? max dose if chronic alcoholic or underlying liver disease?
max dose = 4g/day
max dose if chronic alcoholic or underlying liver disease = 3g/day
when do you use caution with APAP?
liver disease/ETOH
what NSAID is preferred over Ibuprofen for arthritis?
Naproxen b/c only needs to be taken BID rather than QID
always tell patient to take NSAIDs with?
food - will reduce dyspepsia
when do analgesic effects of NSAIDs occur? when do anti-inflammatory benefits occur?
analgesic effects begin w/in 1-2 hours
anti-inflammatory benefits require 2-3 weeks of continuous therapy
topical NSAID? how does it work? available only through?
topical diclofenac
acts primarily by local inhibition of COX-2 enzymes
Available only through PRESCRIPTION
dose of corticosteroid injection for large joints?
1 ml of 80mg of Depo-Medrol
2 ml of Lidocaine w/out Epi and 2 ml of 0.25% Marcaine
dose of corticosteroid injection for medium joints?
1 ml of 80mg of Depo-Medrol
1 ml of 1% Lidocaine without Epi and 1 ml of 0.25% Marcaine
dose of corticosteroid injection for small joints?
- 5 ml of 80mg of Depo-Medrol
0. 5 ml of 1% Lidocaine without Epi
