Knee Flashcards
Medical hx
Hx often leads to correct dx MOI & associated injuries Pop Nature & character of pain Swelling Instability Catching or locking
Meniscus - in general
Consists of fibrocartilage
Can’t see on x-ray
Blood supply of peripheral 1/3 only
Peripheral attachment onto capsule at joint line
Meniscus - normal function
Takes up space
Disburses synovial fluid
Supports approx. 505 of its compartment weight with posterior horn bearing majority of weight
Meniscus Tear - Clinical feature
Medial meniscal injuries most common causes of knee joint pain
Hx of trauma with subsequent knee locking or catching
Pain persists and interferes with weight bearing activity
Meniscus Tear - PE
Inspection - Swelling - Loss of extension Palpation - Joint line tenderness - Effusion ROM
Meniscus Tear - Tests
McMurray’s test
Apley’s test
McMurray’s test
Knee fully flexed, leg externally rotated testing for medial tears and internally rotated for lateral
While maintaining rotation extend knee with a firm controlled movement
Painful click “positive” test
Apley’s test
Pt prone, knee flex at 90°, axial load on heel while leg is rotated internally and externally
Pain “positive” test
Meniscus Tear - dx
X-rays
MRI
ARthroscopy
Meniscus Tear - tx
Ice (acute) Quadriceps exercises Crutches NSAIDS Analgesics Arthroscopy
Meniscus Tear - when to refer
Locked knee or lack of full extension
Persistent pain and/or swelling
Giving way
Ligamentous injuries
Anterior & posterior cruciate
Medial and lateral collateral
Anterior cruciate injury
Results from traumatic injury
Torn more commonly than PCL
Primary anterior and rotational stabilizer of knee
May occur with associated injury, meniscal or medial collateral tear
ACL injury - Clinical feature
Hx of significacnt twisting injury
Popping sensation at time of injury
Hemarthrosis found 75% - rapid
Giving way - acute or chronic
ACL injury - PE
Inspection - swelling
Palpation - effusion & pain
ROM - painful
ACL injury - Tests
Lachman’s Test
Anterior Drawer
Pivot Shift
Lachman’s Test
More sensitive
Knee flexed 30°
Anterior/posterior translation of tibia
Pivot shift
Knee fully extended
Valgus and upward force applied to knee
Tibia subluxes anteriorly on femur
Knee flexed produces reduction of tibia
ACL injury - imaging
X-rays - avulsion
Arthrocentesis
MRI - gold standard
ACL injury - tx
RICE Knee immobilizer Crutches NSAIDS Arthrocentesis Therapy Sx
ACL injury - when to refer
Acute injury
Presence of effusion secondary to trauma
Posterior cruciate injury - in general
Direct trauma to proximal tibia when flexed knee is decelerated rapidly - dashboard injury
PCL injury - tests
Posterior drawer test
Tibia sag test
Posterior drawer test
Posterior displacement of tibia on femur
Collateral ligament injury - in general
Medial & lateral stabilizer Medial collateral (MCL) Lateral Collateral (LCL) Traumatic partial or complete tear May occur with meniscal, ACL, PCL injury
Collateral ligament injury - clinical features
Able to ambulate C/o swelling or stiffness Pain Tenderness Localized ecchymosis Swelling possible
MCL injury - MOI
Valgus force
LCL injury - MOI
Varus force (less common)
Collateral ligament injury - PE
Examine normal knee first Inspection - swelling - ecchymosis Palpation - tenderness about origin & insertion of ligament ROM
Collateral ligament injury - tests
Valgus and varus stress tests
Perform with knee in full extension and 30° flexion
Collateral ligament injury - dx
Radiographs usually negative - possible avulsion
Collateral ligament injury - Grade I
Localized tenderness over ligament
Little or no laxity
Tx with RICE & NSAIDs short term
Collateral ligament injury - Grade II
Significant laxity, but definite end point reached
Tx with hinged brace 4-6w & allow WBAT
Collateral ligament injury - Grade III
Laxity with no end point
Hinged brace, gradual return to FWB
Rehab - early ROM & quad strengthening
Refer for possible sx
Collateral ligament injury - when to refer
Hemarthrosis
Ligamentous instability
Tendinitis
Overuse syndrome
Quadriceps tendon & Tendinitis
At insertion on superior pole of patella
Patellar tendon & Tendinitis
At inferior pole of patella or insertion at tibial tubercle (jumper’s knee)
Tendinitis - clinical symptoms
Anterior knee pain
Night pain
Pain with sitting, squatting or kneeling
Increased with climbing stairs
Tendinitis - PE
Palpation - pain
Quadriceps atrophy
Check straight leg raise to r/o rupture
Check ACL & PCL
Tendinitis - Dx
MRI is helpful if conservative tx fails
Tendinitis - tx
Rest Knee immobilizer intermittently NSAIDs - short term AVOID STEROIDS Strength and pain free motion Refer all possible tendon ruptures
Osgood-Schlatter dz - in general
Seen in adolescents (12-14yo)
Repetitive injury
Occurs at bone tendon junction-patellar tendon & tibia tubercle
Osgood-Schlatter dz - clinical features
Pain Swelling Tenderness Relieved by rest irregular ossifications or fragmentation of tibial tubercle on lateral x-ray
Osgood-Schlatter dz - tx
Avoid activity triggering s/s Ice Immobilization for severe s/s Parental reassurance Sx rare
Patellar fx - in general
Direct blow while quadriceps is under tension
Patellar fx - clinical features
Pain
Inability to extend knee
Patellar fx - PE
Hemarthrosis with swelling
Unable to extend knee
Open fx common due to direct blow
Patellar fx - dx
AP & lat s-rays
Extensor mechanism usually intact if two main fragments <6mm apart
Patellar fx - tx
immobilize in extension 6 weeks (3-4 weeks ROM)
- if < 5mm separation & <2 mm displacement
- extension intact
Sx
Dislocations - in general
C/o knee giving way or popping out May occur secondary to acute injury May spontaneously reduce with gradual extension Evaluate for other injuries F>M
Patellar Dislocations - tests
Positive Apprehension test
Patellar Dislocations - Tx
Aspirate tens hemarthrosis
Immobilization (2-6 wks)
Full weight bearing
Quadriceps exercises important!!!
Patellofemoral Pain Syndrome - in general
Chondromalacia pateleae
Most common anterior knee problem
Worse with sitting with knee flexed (theatre sign) or going down stairs
Patellofemoral Pain Syndrome - dx
X-ray usually show negative, sunrise films may show lateral displacement of patella
Patellofemoral Pain Syndrome - tests
Positive patellar compression
Entrapment signs
Entrapment sign
Weak quadriceps
Patellofemoral Pain Syndrome - tx
NSAIDs Ice Quadriceps exercise Avoid triggering activities Sx if conservative tx fails
Fx of the knee joint
May are intra-articular Tibial plateau & femoral condyles - MOI Clinical feature Tx
OA - in general
Common cause of knee pain
Progressive breakdown of cartilage and joint (synovial fluid)
Breakdown causes a loss of the cushioning and lubrication that cartilage and joint fluid give to the knee joint
OA - s/s
Pain Stiffness Functional impairment Swelling Grating & catching when knee is bent
OA - RF
Increasing Age Excessive weight Overuse of the knee Injury to the knee A FHx of OA
Healthy knee
Bone ends are protected by healthy cartilage
The space between bones is well lubricated with healthy joint fluid
Cartilage
A cusiony substance that keeps bones from rubbing together
Mild OA
Cartilage surface stats to break down
Moderate OA
Cartilage continues to break down and is more easily damaged by everyday ear and tear or injury
Joint fluid starts to lose its lubrication and shock-absorbing ability
Severe OA
Large amounts of cartilage have worn away, allowing bones to rub against each other
Bone spurs form on the ends of bones
Treating OA knee pain summary
Non-drug therapies include - exercise, weight loss, heat & cold & PT
Drug therapies include - acetaminophen, NSAIDs topical therapies, injectable corticosteroids & viscosupplements
Viscosupplements replace dzed joint fluid
