Knee pain and other concerns Flashcards
meniscus injury presentation
acute or subacute symptoms small effusion locking sensation with extension inability to fully extend joint line tenderness positive McMurray’s test
cruciate ligament injury presentation
acute pop with rapid onset large effusion and hemarthrosis anterior cruciate anterior drawer and lachman tests are positive posterior cruciate (uncommon) posterior drawer test is positive
collateral ligaments
effusion uncommon medial collateral - instability with lateral movement valgus laxity lateral collateral - instability with medial movement or varus laxity.
Popliteal cyst (baker’s cyst)
from extrusion of fluid from knee joint into space around the semimembraneousus/gastrocnemius bursa
popliteal cysts are synoival fluid containing extension of the knee joint space and can occur from inflammatory arthritis, osteoarthritis or traumato the knee
see swelling of the popliteal fossa on PE.
risk factors for popliteal cyst
trauma (meniscal tear) underlying joint dx (osteoarthritis and rheumatoid arthritis)
clinical presentation of baker’s cyst
asymptomatic bulge behind the knee that diminishes with flexion and posterior knee pain and swelling and stiffness
complications of baker’s cyst
venous compression - leg and ankle swelling, dissection into calf (erythema, edema and Homan’s sign) cyst rupture - acute calf pain and warmth and erythema and ecchymosis
dissecting baker’s cysts
sometimes called pseudo thrombophlebitis - causes exquisite calf pain. can have positive Homan’s sign and mild edema.
Physical exam shows prominent medial politeal fullness with patient standing and knees extended.
Swelling tends to decrease with knee flexion to 45 degrees (foucher’s sign)
Diagnosis of baker’s cyst
clinically made on physical exam but U/S can help differentiate between thrombophlebitis and dissecting synovial cyst. MRI may neded if ultrasound is inconclusive or suspect issue with knee.
patellofemoral pain syndrome
affects younger pts involved in sports and athletic activities such as running. See increasing levels of physical activity and see retropatellar pain with direct compression of patella during knee extension. No joint effusion or joint space narrowing.
predisposition for septic knee joint?
damaged joints (RA) but many with RA pts with septic arthritis do not present acutely and may not have feers, chills or peripheral leukocytosis.
pseudoseptic arthritis in RA pt
may have synovitis and marked synovial fluid leukocytosis but must always tap joint to make sure it’s not septic.
synovial fluid analysis of septic joint
50-150K WBCs and sudden onset knee joint pain and swelling and inability to move joint and see nausea and weakness. Also with fever
what should you also check when you are ordering synovial fluid status for someone with suspected septic joint?
get blood cultures (50% of the time) also get synovial fluid analysis and culture and gram stain
treatment of septic joint
needs to get IV antbiotics (at least 6 weeks)
knee pain and swelling 3 months after arthroplasty; need to consider:
aseptic mechanical complicaiton of prosthesis or early onset prothetic joint infection
presentation of prosthetic joint infection
see persistent pain, localized or systemic symptoms of infection (joint effusion, wound drainage, fever, erythema, induration and edema)
when do we see prosthetic joint infection after arthroplasty?
early <3 months delayed 3-12 months late onset (>12 months after surgery
How do we diagnose prosthetic joint infection?
XR not good enough need diagnostic arthrocentesis in suspected PJI unless open surgical drainage is anticipated and obvious sign of infection such as a sinus tract is present
What labs to send on diagnostic arthrocentesis (joint tap)?
synovial fluid analysis with cell count and differential get gram stain and culture for aerobic and anaerobic organisms get ESR and CRP and blood cultures
what to do for prosthetic joint infection
early onset prosthetic joint infection - improves with surgical debridement followed by prolonged abx delayed or late onset prosthetic joint infections - require prosthesis removal if debridement shows an infected prosthesis.
Do we ever give abx prior to joint aspiration in suspected septic joint?
no because we want to maximize the yield of synovial fluid culture and direct antibiotic therapy
do we ever get a technetium 99 m colloid bone scan for suspected prosthetic joint infection after arthroplasty?
no because in early months post surgery there could be high false positive result due to periprosthetic bone remodeling.
common overuse injuries to the knee include:
patellofemoral syndrome iliotibial band syndrome pes anserine bursitis patellar tendinopathy prepatellar bursitis
poorly controlled anterior knee pain with pain with squatting and this condition is commonly seen in runners or women.
patellofemoral syndrome
poorly localized lateral knee pain with tenderness at the lateral femoral epicondyle with flexion and extension. See this in runners and cyclists
iliotibial band syndrome- diagnosed on history and physical exam findings. See tenderness at the lateral femoral condyl esp during flexio nand extension of the knee. MRI will show signal intensity abnormalities in soft tissues in the deep IT band nad sensitivity at experienced centers.
This is primary biochemical and need to reduce intensity and duration of running sessions and begin a advised to reduce strengthening exercises and stretching.
highly localized medial knee pain with point tenderness at the pes anserine bursa and seen with OA and DM2 pts
pes anserine bursitis
localized pain in the inferior patella and tenderness at tendon insertion at the inferior patellar margin and commonly seen in jumping sports like basketball and volleyball
patellar tendinopathy
anterior knee bogginess and tenderness with propensity to secondary infection with Staph and see commonly in pts who work on their knees
prepatellar bursitis
housemaide knee
prepatellar bursitis.
meralgia paresthetica is
lateral thigh symptoms in obese pts who have compression of lateral femoral cutaneous nerve at the waist due to wearing tight fitting clothing. see sensory finginds at the specific area at the lateral and anterior thighs
anserine bursitis
knee pain in inexperienced runners. Unlike this anserine bursitis will have well localized pain at the medial aspect of knee and tx has been NSAIDs and steroid inections
patellofemoral syndrome:
reproducible pain with squatting. Like IT band syndrome it is treated with stretching and strengthening and exercises. Knee brace is recommended but no evidence proving it’s usefulness.
pes anserinus pain syndrome
see medial knee pain and focal tenderness
sometimes called anserine bursitis and most pts don’t have true inflammation of the bursa and multiple structures can cause pain
Can be caused due to medial compartment knee osteoarthritis trauma or increased mechanical stress from running or obesity
see in females, obese women, diabetics, and physically inactive. diagnosis is clinical and conservative management is required.
pes anserinus pain syndrome pain is located
localized pain over the anteromedial tibia and exacerbated by pressure from opposite knee while lying on side. See well defined area of tenderness over the medial tibila plateau below the joint line.
Diagnosis is by clinical picture
management of pes anserinus pain syndrome or anserine bursitis
acute therapy: avoidance of crossing legs, limiting repetitive knee pbending nad decreasing pressure on the area by placing a pillow between the knees at night and applying ice to reduce pain.
NSAIDs are for pain relief but these rarely can help as they don’t concentrate well in isolated anserine bursa.
if symptoms don’t improve may benefit from steroid injection.
Valgus stress maneuver
patellofemoral pain syndrome is the
most common cause of non traumatic knee pain
due to overuse, malalignment, trauma.
Diagnosis is based on history and exam
patellofemoral pain syndrome presentation
_achy or sharp pain around the patell_a. Can have “locking” but only true “locking” is from intraarticular knee joint injury or meniscal injury with joint effusions.
provocating pain - knee pain can worsen with prolonged rest and with squatting, running and going up and down stairs.
see as affected knee giving away or buckling and symptoms should not be confused with ACL injury.
how to treat patellofemoral pain syndrome?
supervised physical therapy with activity modfication and quadriceps plus hip abductor strengthing for at least 6-12 months is mainstay.
NSAIDS and knee bracing doesn’t help
knee pain that worsens with squatting
see mild crepitus and tenderness on direct compression of the patella during knee extension
patellofemoral pain syndrome. need supervised physical therapy
treatment of symptomatic popliteal cyst?
ibuprofen and another NSAID for treating underlying cause of cyst.
what can happen to popliteal cysts?
they are normally asymptomatic but can form large outswellings nad rupture which can cause significant pain and swelling of calf
can mimic thrombophlebitis
knee should be examined for meniscal pathology, effusion, and mechanical signs that indicate intraarticular irritatant causing excessive fluid shift.
