Ortho: Knee Flashcards
Knee pain can be broadly categorized as due to one or more of the following
- An intraarticular process such as a meniscal or ligamentous injury (internal derangement) or fracture
- Patellar malalignment or dysfunction
- Cartilage loss due to osteoarthritis or synovitis
- Periarticular bursitis or tendinopathy
- Referred pain from the hip, femur, or spine
- Inflammatory arthritides (synovitis)
Symptoms that are most important in arriving at a specific anatomical diagnosis
localized pain, focal swelling, inflammatory changes, and abnormal noise (clicking, popping, grinding).
Symptoms that suggest the presence of a joint effusion
generalized swelling and the mechanical consequence of the effusion, namely impaired bending
Symptoms that reflect a change in overall knee function
complaints of loss of muscular or ligamentous support (weakness, giving out, collapsing), loss of smooth movement (catching, “something is wrong inside”), and difficulty with ambulation (limping, fatigue, favoring).
Common causes of medial knee pain include
osteoarthritis, pes anserinus pain syndrome (formerly anserine bursitis), medial collateral ligament injury, and medial meniscal tear
Causes of anterior knee pain include
injuries to the quadriceps muscles or tendon, patellofemoral pain syndrome, advanced osteoarthritis, prepatellar bursitis, patellar tendinopathy, patella injury, and inflammatory or septic arthritis
Causes of lateral knee pain include
osteoarthritis, iliotibial band syndrome, lateral collateral ligament injury, and lateral meniscal tear
Posterior, or popliteal, knee pain
muscle or neurovascular injury, including deep vein thrombosis
Ultrasonography of knee to pick up
Baker’s cyst, meniscal cyst or synovitis
MRI knee
soft tissue pathology is suspected (eg, chronic tendon or meniscal tears, focal articular cartilage damage, or plica syndrome) osteomyelitis, osteonecrosis, and stress fractures
CT knee
assess for fractures that are clinically suspected but are not apparent on plain radiographs and to further assess and aid in preoperative planning for complex fractures
osteoarthritis
joint pain, stiffness, and locomotor restriction. They usually present in just one or a few joints in a middle-aged or older person. knees, hips, interphalangeal joints, first carpometacarpal (CMC) joints, first metatarsophalangeal (MTP) joints, and apophyseal (facet) joints of the lower cervical and lower lumbar spine
Generalized OA
polyarticular subset of OA involving the distal interphalangeal (DIP) joints, thumb bases (first CMC joints and trapezioscaphoid joints), first MTP joints, lower cervical and lumbar facet joints, knees, and hips.
Peripheral joint OA
-Persistent usage-related joint pain in one or few joints
- Age ≥45 years
- Morning stiffness ≤30 minutes
patellofemoral pain syndrome
anterior knee pain common in those < 40 and those with advanced osteoarthritis can be unilateral or bilateral “runners knee”
prepatellar bursitis
anterior knee pain with swelling and inflammatory changes anterior to the patella
patellar tendinopathy
“jumpers knee”, focal knee pain at the patellar tendon usually involves a minor tear at the patellar tendon seen commonly in athletes, Often the tendon feels very stiff first thing in the morning
septic arthritis knee
diffuse anterior knee pain, swelling and impaired flexion prefer to keep the knee slightly flexed
Lateral knee pain
lateral osteoarthritis, injured lateral collateral ligament, lateral meniscus tears
IT band syndrome knee pain
focal lateral pain at the femoral condyl showing inflammation of the IT band. Can be from worn shoes, excessive running, or running on uneven terrain. Aching or burning pain over the lateral femoral condyl and can radiate toward the hip.
Clicking, popping, snapping knee
patellofemoral syndrome, IT band syndrome, meniscus tear
Classic critera for knee osteoarthritis
greater than 50 years of age, morning stiffness less than 30 minutes, crepitus, bony tenderness, bony enlargement, no palpable warmth. XRay shows a decrease in cartilage space and adjacent osteophyte formation
Synovial effussion
Intraarticular pathology can be septic arthritis, IBD – gout, RA, tumor, infection.s/s knee swelling, knee tightness, restricted ROM.
Hemarthrosis
immediate rapid within 2-4 swelling. -ACL tear most common, can also be MCL or meninscal tear. If no trauma think blood coag disorder
Popliteal cyst
aka Bakers cyst fluid filled mass in popliteal fossa. Popliteal tightness, fullness, impaired bending, medial popliteal mass prominent when standing and goes away when flex 45 degrees
Bursitis
exquisite local tenderness, pain on motion and at rest, occassional loss of active movement, swelling and warmth with prepatellar bursitis
Pes anserinus pain syndrome
Pain when rising from a seated position and goes up or down stairs, between the tibia and sartorius. Pain when on medial region at night. No swelling or warmth. Does have focal tenderness. Common in swimmers.
Prepatellar bursitis
Localized swelling and tenderness anterior to the patella from trauma or kneeling too much due to direct pressure, localized redness swelling and tenderness. Knee motion is unimpaired.
ACL
Trauma, feels loose or giving out, swelling begins shortly after, laxity on Lachman, pivot shift or drawer tests. Noncontact deceleration, cutting movement or hyperextension, w a ‘pop’ and unable to continue sports
Medial collateral ligament
Knee pain along the medial aspect of the joint, difficulty walking, pivoting and twisting. can be inflammed, torn partially or completely.
Lateral collateral ligament
tender along lateral joint line, very uncommon, laxisity or pain during varus stress test
Posterior cruciate ligament
Foot is planter flexed and fall forward or from direct blow during contact sport or MVA striking dashboard. Posterior drawer sign + to diagnose
Meninscal tear
Loss of smooth motion (locking) knee effusion and premature osteoarthritis. Twisting knee w foot fixed on the ground. Need MRI or diagnostic arthroscopy.
Anterior drawer test
subluxating the tibia anteriorly with the knee 90 degree flexion. Any gross movement is abnormal. posterior drawer is done if there is PCL tear.
Lachman test
knee in 30 degree flexion stabilize femur and apply anterior force to the tibia any laxity is abnormal
Pivot shift test
knee is extended hold tibia in internal rotation positive if there is a clunk or a glide of 20-40 degrees
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McMurray test to assess for
menincus tear
