kin 188 knee injuries and evaluation
TRANSCRIPT
KIN 188 – Prevention and Care of
Athletic Injuries
Knee Evaluation and Injuries
Anatomy
Bony Anatomy
Femur Medial/lateral femoral
condyles
Tibia Medial/lateral tibial plateaus Tibial tuberosity
Fibular head
Patella (“knee cap”)
Ligamentous Anatomy
Anterior cruciate ligament (ACL) – prevents anterior tibial translation
Posterior cruciate ligament (PCL) – prevents posterior tibial translation
Medial collateral ligament (MCL) – protects against valgus stress
Lateral collateral ligament (LCL) – protects against varus stress
Menisci
Medial meniscus Larger, C-shaped
Lateral meniscus Smaller, O-shaped
Muscular Anatomy
Anterior Quadriceps (vastus medialis/intermedius/lateralis, rectus femoris) Primary knee extensors
Posterior Hamstrings (biceps femoris/lateral, semimembranosus and
semitendinosus/medial) Primary knee flexors
Medial Pes anserine (“goose foot”) muscles (sartorius, gracilis, semitendinosus)
Lateral Iliotibial (IT) band
Evaluation
History
Mechanism of injury/etiology Direct trauma (contusion, fracture, bursitis) Hyperextension (ACL/joint capsule sprain) Hyperflexion (PCL/joint capsule sprain) Fall on flexed knee (PCL sprain) Valgus stress (MCL sprain, meniscus injury) Varus stress (LCL sprain, meniscus injury) Rotational stress (ACL sprain, meniscus injury)
History
Unusual sounds/sensationsClicking/locking – meniscus injury“Pop” – cruciate ligament injury, patellar
dislocation
History of previous injury/surgery
History
Change in activity Intensity, duration, frequency, surface change, footwear change
Acute/gradual onset of symptoms Macrotraumatic vs. microtruamatic
Characterize pain Location (point with 1 finger) Dull, sharp, burning, throbbing, etc. Rate on scale (1-10) What increases or decreases?
Treatment, medication, evaluation to date
Inspection/Observation
ALWAYS compare bilaterally Obvious deformity
Genu valgum (“knock knees”) Genu varum (“bow legged”) Genu recurvatum (“hyperextension”)
Bleeding Discoloration/ecchymosis Swelling
Immediate vs. gradual, amount Scars
Inspection/Observation
Palpation
Patella Femoral condyles Tibial plateaus Tibial tuberosity Fibular head Joint line (menisci)
MCL LCL Infrapatellar tendon Quadriceps Hamstrings Gastrocs
Special Tests
ROM Active – patient/athlete moves joint Passive – clinician moves joint, evaluates end feel Resistive – proximal stabilization and distal
application of resistance (“break” test vs. resistance through ROM)
Neurovascular
Special tests
ROM
Knee extensionPrimary movers are quadriceps
Knee flexionPrimary movers are hamstringsSecondary movers are gastrocs (cross knee
joint posteriorly)
Neurovascular
Neurological evalation Nerve root level and peripheral nerve sensory and
motor distributions
Vascular evaluation Skin temperature/color Capillary refill Popliteal pulse Dorsal pedal pulse Posterior tibial pulse
Special Tests
Anterior drawer/Lachman tests – ACL
Posterior drawer/posterior sag tests – PCL
Valgus stress tests – MCL
Varus stress tests – LCL
Apprehension test – patellar instability
McMurray’s/Apley’s tests - menisci
Injuries
Ligamentous Injuries
ACL injuries
PCL injuries
MCL injuries
LCL injuries
ACL Injuries
Most MOI are non-contact rotational forces
Tibia displaced anteriorly on femur (or vice versa), rotational stress (cutting) or hyperextension
May be isolated, but typically due to MOI, other structures (joint capsule, menisci) also injured
Positive anterior drawer and/or Lachman’s tests
PCL Injuries
Most common MOI is fall on flexed knee driving tibia posterior on femur
May also occur with rotational and/or hyperextension MOI
Often treated non-operatively as quadriceps muscles are able to minimize posterior displacement of tibia on femur
Positive posterior drawer and/or posterior sag tests
MCL Injuries
Most common MOI is blow to lateral knee with resulting valgus tension forces
May also be injured by non-contact and/or rotational stresses
Positive valgus stress test
LCL Injuries
Most common MOI is blow to medial knee with resulting varus tension forces
Internal rotation of tibia may be secondary contributor to LCL injury
Positive varus stress test
Meniscal Injuries
May be isolated from flexion/hyperflexion with rotation of the knee – “pinched” between tibia and femur
Often injured in association with cruciate ligament injury
“Classic” symptoms include joint line pain and clicking or locking – helpful but not definitive evaluative tools
Limited reliability of special tests
Patellar Injuries
Lateral displacement is most common
Positive apprehension test
Patellar Tendon Rupture
Occurs with excessive tension through tendon causing failure in mid-substance or at either insertion point
Present with gross deformity, inability to actively extend the knee and significant swelling immediately
Additional Injuries
Muscle strains to quadriceps/hamstrings Severity based upon degree of tissue damage
Tendonitis Overuse condition associated with training changes,
biomechanical insufficiencies, poor flexibility, etc. Most common to infrapatellar tendon, but can involve
IT band, pes anserine muscles and/or hamstrings as well
Additional Injuries
Osgood-Schlatter’s disease Inflammatory condition of tibial
tuberosity at patellar tendon insertion, symptoms similar to patellar tendonitis but tuberosity often enlarged and only site of pain, most prominent in adolescents
Bursitis Typically inflamed secondary
to acute trauma, but may be chronic or associated with infection
Prepatellar, presents with significant anterior swelling