Quiz 3.3 Flashcards
Hip
The junction between the passenger and locomotor units
Ligaments of hip
Iliofemoral, pubofemoral
Iliotibial Tract (band)
Strong, fibrous connection between the TFL and condyles of femur, tibia, and head of fibula
Stabilized knee in extension & partial flexion
ITB Syndrome
Pain, swelling/thickening above/below knee at rubbing points
Pain often occurs when contact with ground occurs
Common in Runners, cyclers, hikers
Hip anterior muscles & adductors
Psoas major, iliacus, adductor brevis longus magnus, pectineus, gracilis
External rotator hip muscles
6
All insert near greater troch and originate at/below acetabulum
PIRIFORMIS
Piriformis syndrome
Irritation of the sciatic nerve to tight piriformis
Pain in butt, tingling or numbness along sciatic nerve
“Sciatica” from lower back or tight piriformis
Often found in run/bike because many repetitions of hip extension leads to tight Piriformis
Other hip muscles
Sartorius, RF, HAMS
Gluteus Maximus
Hip extensor & Abductor
Gracilis
Hip flexor & Adductor
Rectus Femoris
Hip & Knee Flexor
Semimembranosus (HAMS)
Hip Extensor & knee flexor
Semitendinosus (HAMS)
Hip extensor & knee flexor
Biceps Femoris (long head) (HAMS)
Hip extensor & knee flexor
Knee Joint
Largest joint of body
Femur, Tibia, Fibula, Patella
Patella
Site of insertion for Quad; Allows tendons of muscles to slide over femoral condyles
Its movement allows us to increase perp. distance from AOR so we can reduce force while producing equal torque
Amount of articulation of patella and femur changes with flexion angle
Motions of knee
3 DOF
Frontal plane: AB/AD; limited
Transverse: Int/ext rot; limited
Sagittal: Flex/ext: largest ROM
Knee function
Transition GRFs upward to thigh muscles during locomotion
Tibiofemoral joint
Medial and lateral condyles articulate with tibial condyles
“knee”
Patellofemoral Joint
Anterior femur articulates with patella
Protects from anterior knee trauma
Increase MA of quad which allows for max torque production
5 ligaments of knee
Lateral and medial Collateral lig (LCL & MCL)
Anterior and posterior cruciate ligaments (ACL & PCL)
Anteriolateral ligament (ALL)
Primary similarity between ACL and PCL
Resist sagittal plane movement
Characteristics of ACL
Resists forward movement of tibia
Originates at lateral condyle femur
Inserts on tibia
2 bundles: Anteromedial, posterolateral
Injury more common because can happen with no contact or force from behind
Anterior drawer test
Characteristics of PCL
Resists movement of tibia backwards
Originates on posterior intercondylar Tibia
Inserts on medial condyle Femur
One bundle
Injury less common because we are better at absorbing force coming from in front of us
Posterior drawer test
Can ACL heal itself
Does have blood supply and innervation, doesn’t get blood from bony attachments
BUT full tear ends cannot reattach
Healing on its own leads to over stretching and weaker than original which could lead to re-tears
Why does ACL strengthening focus on HAMS
They prevent tibia from moving forward because they insert on post. tibia so can help ACL handle force
ACL Repair vs. reconstruction
Repair: Partial tear, just reattach
Reconstruct: Replacing torn ACL with harvested tendon
Unhappy triad
Injury to knee involving 3 ligaments
ACL, MCL, Medial meniscus
Occurs when force applied while foot is fixed and force applied above/below knee (often with rotation)
Menisci
Reduce bone-bone contact between femur and tibia; disperses body weight and reduces friction
Medial and lateral
Medial larger because more force occurs through midline due to body weight distribution
Bursae
Fat sacks in knee
Suprapatellar
Prepatellar
Infrapatellar
Semimembranosus
Menisci structure
Wedge shape, thicker on periphery for stability in frontal plane as weight shifts, keeps femoral condyle alignment
Outer third has blood supply, inner 2/3 has no blood supply
Medial meniscus
Pulled posterior by semimembranosus
Lateral Meniscus
Pulled posterior by popliteus
Menisci function
Reduce compressive stress, stabilize joint during motion, guide knee, shock absorption, proprioception
Popliteus muscle
Unlocks knee when flexion is initiated by laterally rotating femur
“Dropping groomsmen”
At full leg extension knee locks because femur medially rotates
Why does medial head of gastrocnemius produce greater force
Medial is used more in walking because we push off big toe (medial) and our mass is more medial
Greater pennation angle on medial head
Plantaris
Knee flexor & plantar flexor
More knee focus
Gastrocnemius
Knee flexor & Plantar flexor
More ankle focus
