hip and knee mechanics Flashcards
What are the major motions of the hip?
FlexionAbductionAdductioninternal and external rotation
Dysfunction of tensor fascia lata
Frequently seen with lateral hip and knee pain
Tightness of adductor muscles
Frequently results in inferior pubic symphysis shear - dysfxn of pubic symphysisFrequently seen with persistent groin pulls
Tightness of piriformis muscle
Tightness will decrease hip internal rotation and may irritate the sciatic nerve
Hip disfunction
Associated with decreased hip extension due to - decreased hip extension due to psoas major mm - decreased internal rotation due to piriformis m, tensionResponds well to OMM, muscle energy techniques
Acetabular labrum Tear
Symptoms:sharp, deep pain anterior thigh/groinworsens when rising from a seated to standing positioncan click with motion
Hip Pearls
Compare injured and uninjured sideExamine joint above and below injured area for other potential problemsWith intraarticular hip problems, the first motion lost is typically internal rotation
Motions of the Knee
Flexion and ExtensionMinor gliding motions of tibial plateau include:anterior/posterior glidingmedial/lateral flidinginternal rotation with posterolateral glidingexternal rotation with anteromedial gliding
Knee “screw home” mechanism
Allows lower extremity to fxn as a solid columnWith knee fully extended the knee passively locks due to medial rotation of the femoral condyles on the tibial plateau
Knee Restrictions
Restrictions involving the gliding motions are frequently associated with somatic dysfxn
History of subjective knee instability
Sometimes indicates meniscal tear
Knee joint locking
Can indicate a very significant meniscal tear - indication for an MRI and probable surgery - can have less severe meniscal tear without joint locking
Palpating menisci
Lateral joint line tenderness, or palpable TART - can indicate lateral meniscal tearMedial joint line tenderness, or papable TART - can indicate medial meniscal tearTenderness in popliteal fossa may indicate a tear of the posterior horn of either meniscus
Terrible Triad
AKA Unholy triad. O’Donoghue’s triad - MCL, medial meniscus, and ACL tear
Flexors of the leg include
Biceps femoris, semimembranosus, semitendinosus, popliteus, and gastrocs
Dysfxn of leg flexors
Associated with posterior knee painExcessive tightness will limit knee extension
Extensors of the leg include
Rectus femorisvastus lateralisvastus medialisvastus intermedius
Dysfxn of leg extensors
Associated with anterior knee painExcessive tightness will limit knee flexion
Movement of the fibular head
Allows for anterolateral and posteromedial gliding of fibular headFibular Reciprocal MotionFibular head moves in combo with lateral malleolus - when head moves anteriorly, lat malleolus glides posteriorly and vice versaInversion ankle sprains may result in restriction of lateral malleolus and fibular head
Fibular head restrictions
Often with hamstring strains and injuries to lateral collateral ligamentIf restriction persists despite treatment, may be associated with injury to lateral meniscus
Somatic dysfxn of the knee
Often associated with restriction of tibiofibular joint - lateral knee pain - common fibular nerve runs near herePosterior fibular head may affect fxn of this nerve and contribute to foot drop
Lower limb arterial supply
Mostly from femoral aa - affected by sympathetics from T10-L3\ - somatic dysfxn affecting these levels can increase sympathetic tone to lower limb and decrease aa supply
