Pathologies Related To The Knee Flashcards
What is deep vein thrombosis?
- partial or complete occlusion of a vein by a clot
What are risk factors for DVT?
Conditions involving at least 2 of the following:
- venous stasis
- hypercoagulability
- damage to the venous wall
What is the etiology of DVT?
- 50% unknown
What are some possible contributors to DVT?
- Prior DVT
- Hx of cancer, CHF, or lupus
- Recent and major infection, surgery, or trauma
- Present chemotherapy, immobility, or pregnancy
- Use of oral contraceptives or hormone therapy
- Clotting disorder
- > 60 yrs. of age
DVT is the __ most common cardiovascular disease
3rd
Where is DVT most common?
in LE deep veins (90%)
Why should we be concerned with a DVT after a total joint replacement?
- MOST common cause of readmissions and death after TKA/THA
What should we know about hospital related deaths from DVT?
PREVENTABLE
What is the pathogenesis of DVT?
- Greater exposure of platelets and clotting factors to damaged venous wall
- Fibrin, leukocytes, and erythrocytes adhere and form thrombus
- Basically, the reparative process goes bad
What can be done to treat DVTs?
- Early and regular exercise
> As prevention for sure
> May need to wait on anticoagulant therapy to take effect to avoid a PE from motion with treatment - Anticoagulants
- Compression stockings
- Intermittent Pneumatic Compression devices
- Avoid SAD
- Eliminate persistent smoking and drinking
What will we find in a pt’s history with DVT?
Hx including:
* ~50% asymptomatic in early stages
* Typically, gradual onset of dull ache, tightness, and P! in the calf with prior mentioned risk factors
What is included in the CDR for DVTs?
- Edema: Likely pitting (70% of patients)
- Increased calf girth
- Calf pain and tenderness
50% of patients - Worsened with walking and possibly with dependent positions
- Less and less relief with rest and elevation as condition worsens
What will we find with palpation with DVT?
possible redness and warmth
What is the referral with DVT?
- per CDR:
- urgent if ≤ 17% probability of DVT with ≤ 2
- emergency if 75% probability of DVT with ≤ 3
What can a DVT lead to?
Pulmonary Embolism
What is a pulmonary embolism?
Pathogenesis- DVT that moves and lodges into smaller artery supplying the lungs
What should we know about clinical manifestations of a PE?
Often non-specific… “the great masqueraders”
What are the MOST common S&S of a PE?
SOB, wheezing, and/or rapid breathing may be the only symptom
> Pleuritic chest P! (T2-4 shared innervation)- sudden, sharp and stabbing chest P! possibly exacerbated by:
* Deep inspiration
* Coughing
* Mechanical pain may occur due to lung fascia attaching to ribs and thoracic vertebra
* Trunk motion
* UE motion
* Thoracic and rib accessory motion testing
What are some other clinical manifestations of a PE that are potentially less common?
- Bloody cough
- P!ful breathing at rest
- Fainting
- Tachycardia and palpitations
What is the referral with a PE?
Urgent if < 2/6
Emergency if ≥ 2/6
What is a part of the CDR with a PE?
- Clinical S&S of DVT (i.e., LE swelling; TTP along deep veins; pitting edema; collateral and NOT varicose veins
- HR > 100 bpm
- Immobilization/Sx in prior 4 wks.
- Prior DVT/PE
- Bloody cough
- Malignancy or cancer Rx in last 6 mths.
- Alternative dx is LESS likely than PE
What is peripheral arterial disease?
ischemia leading to symptoms in the MOST distal area from the blocked a.
Where is PAD most often?
in LEs and in calf
What are some risk factors/etiologies for PAD?
- ≥ 45 yrs. of age
- Family hx of MI or sudden cardiac death before 55 yrs.
- Recent or current smoker
- Physical inactivity
- Metabolic syndrome
What is the pathogenesis of PAD?
Atherosclerosis or plaque build up in aa that also promotes vascular constriction thus further limiting circulation
When do symptoms begin with PAD?
once 50% of a. is narrowed
What are some clinical manifestations and S&S of PAD?
Intermittent claudication
* LE P!, MOST often the calf, with walking and elevated positions
* Unilateral or bilateral
* Often described as cramping but also may be weakness, pressure, or aching
* Relieved with rest and dependent position
What will we find distal to the ischemic area with PAD?
- Loss of pulses
- TTP
- Muscle atrophy and weakness
- Loss of hair
- Cool and bluish skin
- Bruit on auscultation
- Possible necrosis/wound
What can happen in the presence of SEVERE ischemia?
the P! may also occur at rest and create sleep interruptions
How do we test for ankle brachial index (ABI) with PAD?
IN SUPINE
- Assess posterior Tibial/Brachial SYSTOLIC BP in all 4 extremities
- Divide ankle by brachial pressure
What makes the ABI invalid?
hx of HTN
What is an abnormal finding with ABI?
- < .9 (the lower the worse the dz)- LR+ = 1.6-7.6; LR- = .0-.86
- ≥ 1.4 (aa. unable to be compressed vv. due excessive hardening from atherosclerosis)
How could you differentiate calf pain due to PAD vs stenosis?
- symptoms (thorough hx)
- Lumbar stenosis with Bicycle Test
- DVT which is more P!ful in a dependent position and relieved with elevation
What kind of referral is PAD?
Urgent referral to vascular MD
What is osteochondritis dissecans?
changes to subchondral bone
Is osteochondritis dissecans common?
no RARE
What population/body part is osteochondritis dissecans MOST common in?
… younger biological boys through early adulthood
… in medial Femoral condyle and Talus
What is the etiology of osteochondritis dissecans?
- MOSTLY unknown
- Joint rotational or shearing trauma, like a sprain
What are the pathomechanics and pathogenesis of osteochondritis dissecans?
- Fracture to subchondral bone involving cortical plate and cancellous bone
- Possible ischemia (AVN) then separation of subchondral bone from convex weightbearing end of bones
- Overlying articular cartilage can remain viable
What are the clinical manifestations and S&S of osteochondritis dissecans?
- Persistent pain, not progressing as expected
- May progress into severe pain if fragment displaces with joint locking, catching, and swelling
- S&S of hypermobility/instability of involved ligament but with persistent age-related joint-like changes
What will we find in our scan with osteochondritis dissecans?
- ROM- limited and painful, particularly with ext
- Resisted/MMT- may be weak and painful, particularly at end range ext
- Compression likely (+) and distraction relieving
What will we find in our biomechanical exam with osteochondritis dissecans?
- Stability tests (+) for specific ligament(s)
- TTP over femoral condyle
What kind of referral is osteochondritis dissecans?
Urgent referral to MD
What is osteochondritis dissecans BEST imaged by?
MRI
Why couold it take up to 2-3 years to revascularize and heal with osteochondritis dissecans?
May take up to 2-3 years to revascularize and heal if the following joint stresses are present:
- Higher BMI
- Deficient passive restraints
- M. imbalances
- Impaired proprioception
What is protection to avoid separation of subchondral bone and articular cartilage into the joint also called?
joint mouse
Why is a joint mouse common at the knee?
loss of joint surface congruancy
What should we treat non-operative stable lesions like?
Rx as joint hypermobility/instability with Age-related Joint Changes
What could surgery be for with osteochondritis dissecans?
resurfacing or fixation needed for unstable lesion
What is reactive arthritis?
- Aka Reiter’s Syndrome
- Acute, infection at a site remote from the primary infection
(Septic arthritis is an infection at the site of primary infection)
What are risk factors for reactive arthritis?
IV drug users
High sexual activity
Infrequent pelvic examinations
Weaker immune system
What does reactive arthritis usually target?
targets larger joints in the LE and primarily the knee and ankle
What is the etiology of reactive arthritis?
- MOST commonly from a respiratory infection
- Also, may occur from GI, genitourinary and colon infection
What is the pathogenesis of reactive arthritis?
bacteria stimulates antibody and protein factor production that creates inflammation and tissue damage leading to an arthritic joint
What are clinical manifestations of reactive arthritis?
- Begin 1-4 weeks after a recent infection
- Infection S&S
- May progress to incapacitating illness
What will we observe with reactive arthritis?
Redness
Swelling
What will we find with vital signs with reactive arthritis?
temperature
What will we find in our scan and biomechanical exam with reactive arthritis?
Like for Age-related Joint Changes
What will we find with palpation with reactive arthritis?
TTP and warmth
Swollen and tender lymph node(s)
What kind of referral is reactive arthritis?
Urgent referral to MD
