MEDD421 Final Exam Flashcards
Why do closed chain kinetic exercised after ACL surgery?
because they reduce anterior-directed forced on the tibia relative to the femur and increase tibiofemoral compressive forces
Perimysium
The connective tissue that surrounds a bundle of muscle fibres.
A pathological fracture is one that…
Occurs in a bone that is already weakened due to underlying pathology
how much dietary Ca is needed daily?
1200 mg
What is the name of the main fibrinolytic enzyme generated by the use of tPA
plasmin
Explain the process of initial assessment of complaints suggestive of PE
- Assess using Wells and/or Geneva criteria
- Low or moderate probability (4 or lower) –> do a D-Dimer
- Positive D-Dimer or high probability proceed to CT
When to consult nephrology for dialysis
A- acidotic E - electrolyte imbalance (hyperkalemia) I - ingestion of toxic drugs O - volume overload U - uremia (confusion, pericarditis)
What feature of creatinine makes it an imperfect marker for estimating glomerular filtration rate?
It is secreted by the renal tubules
Best imaging modality for renal colic
CT KUB
The issue with digoxin?
Narrow therapeutic range
what happens to bicarb in kidney disease?
Bicarb goes down because it is being used up to buffer the high levels of acid that are retained in the body as they can’t be filtered out anymore.
Grades of ligament injury
I - sprain - stretched but fibres intact
II - partial rupture but there is an endpoint to stretch on physical exam
III - complete rupture, lost fxn, no endpoint
Stages of tendon and ligament healing
1) Inflammatory (~1wk; recruitment of inflam mediators)
2) Proliferative (several weeks; Fibroblasts proliferate and type III collagen is laid down [scar tissue]; more vascular)
3) remodelling (weeks-months; Fibres become more organized; shift from type III to type I collagen; less vascularized; less cellular)
Best imaging modality for superficial or dynamic muscle structures
US
Ottawa Knee Rule
Indicators for XR knee;
- Age 55+
- Isolated tenderness patella
- cannot flex 90 degrees
- unable to bear wt immediately and in ER for >4 steps
Pittsburgh knee rule
indicators for XR knee
- <12 yrs or > 50 yrs
- unable to walk 4 wt bearing steps
When would CT or MRI be indicated for knee injury?
- Tibial plateau fracture
- No fracture found on XR and you suspect an occult fracture or internal derangement
- Suspicion of additional injury
MRI indicated if suspicion of deep ligament injury (i.e., ACL)
Stages of knee rehab
0: Prehabilitation - before surgery decrease swelling and pain, achieve normal gait and RoM
1: Immediate post-op manage pain and get RoM, strength and walking as tolerated
2: Functional strengthening and prepare for return to play.
3: Return to play
Timeline for return to play after acl surgery
avg 6-12 mo after surgery. ~65% get back to same level of play
Crtieria for return to play post ACL surgery
- no pain or swelling
- full ROM
- > 85% strength quads and hamstrings
- psychological readiness
Estrogen and bone production/resorption?
Estrogen stimulates osteoblasts, which stimulate osteoprotegrin, which is a sequestering protein. It sequesters the RANK ligand to prevent it from binding RANK receptors on osteoclasts
denosumab
a mAb for RANK ligand - the ligand for the RANK receptors on osteoclasts. It mimics the action of osteoprotegrin
What is calcitriol and what does it do
active form of vitamin D. It works with PTH to increase levels of Ca in the blood.
3 major actions of PTH
- Promotes Ca reabsorption at distal renal tubule
- Promotes renal activation of vitamin D (increases Ca levels in blood)
- Regular episodic release of PTH promotes bone growth and mineral deposition. At sustained levels, PTH promotes bone resorption.
Magnesium and Ca hemostasis
Hypomagnesemia can reduce PTH secretion or cause PTH resistance. PTH is responsible for increasing Ca reabsorption. Remember to check and correct Mg igf hypocalcemia is present.
2 major etiologies of hypercalcemia
- Hyperparathyroidism (high PTH)
- Malignancy (low PTH)
Symptoms of hypercalcemia
Stones, bones, thrones, groans, and psychic overtones
Workup for hypocalcemia
Check Ca, PTH and Mg.
- Low Mg can cause hypocalcemia
- PTH will be low if hypocalcemia is due to surgery, autoimmune, congenital hypoplasia/mutation
- PTH will be high if hypocalcemia is due to Vit D deficiency, CKD, sepsis, hemorrhage/surgery
Hypocalcemia with high PTH and high phosphate is likely related to
CKD
osteomalacia
Vitamin D deficiency
How much VIt D should adults >50 y with osteoporosis get?
800-1000 IU (compared to 400 IU recommended for other adults)
Osteoporosis definition
Low bone mass AND microarchitectural deterioration with a consequent increase in bone fragility and susceptibility to fracture.
T score =/< -2.5 SD below mean BMD
Imaging for osteoporosis
Dual Energy Absorptiometry (DXA) followed by comparisons of bone density to WHO population means. =/< -2.5 SD below mean is considered osteoporosis.
Treatment for osteoporosis
Use FRAX score to decide who is at risk of fracture and requires treatment.
- Lifestyle, Ca and Vit D supplementation
- Bisphosphonates (anti-resorpative) first line
- Denosumab (RANK L mAb) 2nd line
Primary hemostasis: Fxn and main players
Stop the bleeding!
VWF binds subendothelial collagen, platelets (platelet plug)