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298 Cards in this Set
- Front
- Back
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Purpose of meniscus? |
shallow seats for condyles of femur |
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what is the meniscus? |
fibrocartilagenous discs on medial and lateral aspects of tibial plateau |
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characteristics of medial meniscus? |
- C shaped - attaches to deep surface of MCL |
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characteristics of Lateral meniscus? |
- O shaped - external border formed by the lateral capsule |
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what anchors the meniscus to the tibia? |
anterior and posterior horns |
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what is the purpose of the coronary ligaments of the knee?
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loose attachments so each meniscus can slide on tibial plateau during active movements |
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how are the menisci attached to each other? |
anteriorly by transverse ligament |
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what are the muscles that attach to the meniscus? |
- semimembranosus - Quadriceps - Popliteus |
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anterior attachment of medial collateral ligament? |
blends with medial patellar retinacular fibers before attaching to medial-proximal aspect of tibia |
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posterior attachment of MCL? |
pes anserine |
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direction of anterior MCL fibers? |
vertical |
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orientation of the anterior MCL? |
oblique -> posterior to anterior |
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Location of the posterior part MCL? |
deep to anterior part |
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attachment of posterior part of MCL? |
- capsule - medial meniscus - thick tendon of semimembranosus |
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what is the primary function of the MCL? |
- restrain excessive valgus stress - ER of the tibia with knee flexed - (ANTERIOR) - resists knee hyperextension |
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Characteristics of Lateral Collateral Ligament? |
- round and very strong cord - blends with tendon of biceps femoris distally |
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attachments of the LCL? |
- fibular head - lateral epicondyle - DOES NOT ATTACH TO MENISCUS |
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what is the primary function of the LCL? |
- limit varus stress - limit hyperextension - limit ER of the tibia |
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characteristics of the cruciate ligaments |
- intracapsular - extrasynovial |
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how are the cruciate ligaments named? |
according to attachments to tibia |
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how are the cruciate ligaments extrasynovial? |
btwn capsule and synovial membrane |
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what movements do the cruciate ligaments resist? |
- extremes of all motions - mostly AP shear forces |
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besides resistance, what is other role of cruciate ligaments? |
- guide arthrokinematics |
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what is the position of the ACL as if moves distal in the joint? |
- oblique - moves anteriorly and laterally |
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where does the ACL attach distally? |
close to midline of lateral condyle of tibia |
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what is the primary function of the ACL? |
- limit ant. translation of tibia on femur (85% of the restraint) |
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what portion of motion is limited by posterolateral bundle of ACL? |
restrain ant. translation from 20 degrees flexion to full ext. |
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what is secondary function of ACL? |
- limit extremes of varus/valgus angulation - limit tibial IR/femoral ER |
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orientation of the PCL? |
more vertical |
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attachments of the PCL? |
- originates from antero-lateral aspect of medial femoral condyle - attaches to posterior intercondylar area of tibia |
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thickness of PCL? |
twice as thick as ACL |
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characteristics of anterior/lateral bundle of PCL? |
- significantly larger (65%) - taut in knee flexion |
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characteristics of posterior/medial bundle of PCL? |
- slightly oblique (35%) - taut in knee extension |
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Primary function of the PCL? |
- posterior translation of tibia - anterior translation of femur |
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secondary function of PCL? |
- limit extremes of varus/valgus angulation |
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when does max tension of PCL occur? |
full knee flexion |
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what happens without PCL? |
tibia sags posterior on femur |
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where are the attachments of the joint capsule? |
- sides of patella - medial/lateral condyles of femur and tibia |
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anterior capsular reinforcements? |
- Quads - patella - retinacular ligaments |
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medial capsular reinforcements of knee? |
- MCL - popliteus - medial patellar retinacular fibers |
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Lateral capsular reinforcements of knee? |
- LCL - retinacular fibers - Iliotibial band |
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Posterior capsular reinforcements of knee? |
- oblique popliteal ligament - arcuate popliteal ligament |
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posterolateral capsular reinforcements of knee? |
- popliteus - LCL - arcuate popliteal ligament |
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what is the normal alignment of the knee? |
angles medially 5-10 degrees (Genu Valgum) |
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what is the reason for alignment of the knee? |
angle of inclination |
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normal knee alignment produces gapping of what? |
medial femoral condyle from medial tibial plateau |
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normal knee alignment produces compression of what? |
lateral femoral condyle on tibial lateral plateau |
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how does ambulation affect Genu Varum posture? |
- increases genu varum due to heel strike lateral to midline creating net varus torque |
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what is the long term effect of genu varum posture? |
unicompartmental OA |
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what causes excessive Genu Valgum? |
- Coxa Vara - excessive pronation |
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what is the long term effects of Genu Valgum? |
- weakens MCL - increases stress/JRF on lateral compartment |
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what is normal extension posture? |
0-5 degrees |
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what are the characteristics of the line of gravity (LOG)? |
- anterior to knee - slight ext. torque allows quad relax |
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what resists hyperextension? |
- posterior capsule - stretched flexors |
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what is Genu Recurvatum? |
10 degrees or more of hyperextension caused by overpowering ext. torque |
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what disorders cause Genu Recurvatum?
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- Poor posture - Neuromuscular disease |
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what are the movements of the knee? |
- Flexion/Ext. - IR/ER |
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what is the axis of rotation of flexion/ext. at the knee? |
evolute - moves with motion |
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what is the purpose of the evolute axis at the knee? |
alters the length of the moment arm |
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how much ER vs. IR movement is available at the knee? |
2:1 ER:IR |
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basic arthrokinematics of open chain knee extension |
tibia rolls and slides anterior |
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arthrokinematics of last 10 degrees of knee extension |
tibia ER via screw home mechanism |
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action of meniscus during knee extension |
pulled anterior via quad contraction |
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patella motion during knee extnesion |
slides superiorly on femur |
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what causes the screw home mechanism to happen? |
- difference in size between medial and lateral femoral condyle - ACL - action line of the quadriceps |
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how does the difference in size between medial and lateral condyles affect the screw home mechanism? |
smaller lateral condyle completes roll and glide before medial condyle |
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what role does lateral condyle play in screw home mechanism? |
functions as pivot point for medial condyle and results in external rotation |
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what role does the ACL play in screw home mechanism? |
- more taut in extension - pull medial tibial condyle into ER |
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what role does action line of quad play in screw home mechanism?
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contributes to ER due to Q-angle |
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how does a larger Q angle effect the action line of quads? |
- larger q angle means more quad contribution |
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basic arthrokinematics of closed chain knee extension |
femur rolls anteriorly and slides posterior |
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action during last 10 degrees of closed chain knee extension |
- Femur internally rotates |
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Arthrokinematics of open chain knee flexion |
- tibia IR to unlock screw-home mechanism - tibia rolls and slides posteriorly |
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what initiates the IR of tibia to unlock knee? |
popliteus |
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what is the action of the patella during open chain knee flexion? |
slides inferiorly on femur |
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what happens at 100 degrees of knee flexion? |
- tibia tilts away from femur in anterior aspect of joint |
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what has increased tension during knee flexion? |
PCL |
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What posture must the knee be in for IR/ER? |
partially flexed |
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what is the arthrokinematics of open chain rotation? |
relative spin of tibia on femur |
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what does the Q-angle represent |
degree of lateral pull of quad on patella |
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what two lines form the q-angle |
- ASIS to midpoint of patella - Tibial tuberosity to midpoint of patella |
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what is the average Q-angle in men? |
10 degrees |
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what is average Q angle in women? |
16 degrees |
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what is the effect of a higher Q-angle? |
Q-angle higher than 15 degrees is though to contribute to knee pain |
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what plays a large part in determining Q angle?> |
tibial rotation |
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how does rotation effect the Q angle? |
- Tibial IR -> decreases Q angle - Tibial ER -> inncreases Q angle |
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what stabilizes the patellofemoral joint? |
- quads - retinacular fibers - articular surface of patella |
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what compressing the patellofemoral joint? |
- Increased knee flexion - increased quad force demand |
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where is the patella contact when knee is flexed to 135 degrees? |
- Femur at superior pole and rests below intercondylar groove - somewhat located in joint |
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what happens at PF joints as knee extends from 135 degrees of flexion to 90 degrees flexion |
- contact region migrates inferiorly on the patella
- contact area on patella is greater in volume |
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at what point does the patella have the most contact with the femur?
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90-60 degrees of flexion - 30% of total surface area |
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what is the location of contact of PF joint in the last 20 degrees of knee flexion? |
inferior pole contact |
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what is the location of PF jiont at full knee ext? |
rests completely above IC groove against fat pad |
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where is the greatest risk for PF dislocation? |
full ext. |
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what does Q angle produce? |
- natural lateral pull of quads - bowstring force |
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what force counteracts lateral pull of Q angle? |
Vastus medialis |
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what does excessive lateral tracking of Q angle cause? |
- abnormal tilting - shallow IC groove - Increased Q angle |
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what does increased Q angle result from? |
- overstretched MCL - IR/AD hip posture - Excessive foot pronation - Gender |
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what does isometric knee extensor contraction do? |
stabilizes and projects knee joint |
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what does eccentric knee extensor contraction do? |
- controls rate of descent of center of mass (quad) - provides shock absorption |
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what does concentric knee extensor contraction do? |
- controls rate of rise of COM (jumping) - Accelerates knee extension |
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what is the role of the patella? |
displace the quad tendon anteriorly to increase internal MA to give muscle a biomechanical advantage
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how does external moment arm adjust in tibia on femoral knee ext.? |
increases from 90 -> 0 degree flexion - external torque is greatest at full ext. |
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how does external moment arm adjust in femoral on tibia knee extension? |
decreases from 90 -> 0 degree flexion - greatest external force at 90 degrees |
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what is issue with exercise that challenge quads? |
- stress knee joint and can be therapeutic or damaging if PF pain or OA present |
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where is max knee extension torque? |
between 45-60 degrees of flexion |
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what is the torque at the knee between 80-30 degrees of felxion? |
90% of max |
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what is the relationship of internal and external torque at the knee? |
internal torque decreases as external torque decreases |
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when does the flexor-rotator muscles accelerate the tibia in T-O-F knee flexion?
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- concentric contraction when sprinting/uphill walking |
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when does flexor-rotator muscles decelerate the tibia in T-O-F knee flexion? |
end swing phase of walking via eccentric contraction |
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what is the purpose of the flexor-rotator muscle group in Femoral on tibia knee flexion? |
intramuscular synergy of trunk, hip and LE muscle groups |
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what role does the biceps femoris of a planted leg do on F-O-T knee flexion? |
accelerator of IR |
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what role does Pes Anserine of planted leg do on F-O-T knee flexion? |
deccelerator of IR |
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major joints of ankle and foot |
- talocrural - subtalar - transverse tarsal |
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what kind of axis does the foot move on? |
oblique |
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what are the primary movements of the foot |
- supination - pronation |
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what movements make up supination? |
- inversion
- adduction - plantarflexion |
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what movement make up pronation |
- eversion - abduction - dorsiflexion |
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what type of joint is the proximal tibiofibular joint?? |
synovial\ |
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what type of movement happens at the proximal tibiofibular joint? |
- very little superior movement of fibular head |
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what kind of joint is the distal tibiofibular joint? |
syndesmosis |
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what stabilizes the distal tibiofibular joint? |
anterior and posterior distal tib/fib ligaments |
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what is the most common injury of the distal tibiofibular joint and what causes it? |
High ankle sprain - excessive dorsiflexion stretches the interosseous ligament connecting the tib and fib because the ant. portion of the talus is wider than the mortise joint |
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what type of joint is the talocrural joint |
mortise |
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what does the medial collateral ligament (Deltoid ligament) do? |
limits eversion across talocrural, subtalar and talonavicular joints |
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where is the distal attachment of all fibers of deltoid ligament? |
apex of the medial malleolus |
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why are sprains of deltoid ligament uncommon? |
- ligament is very strong - bony block of lateral malleolus |
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what are the 3 sets of fibers of the deltoid ligament? |
- tibionavicular - tibiocalcaneal - tibiotalar |
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where does the anterior talofibular ligament attach? (ATFL) |
ant. lateral malleolus to neck of talus |
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what is purpose of the ATFL? |
inversion and adduction |
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what is unique about the ATFL |
most commonly injured lateral ankle ligament |
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what causes injury of ATFL? |
excessive inversion/adduction, especially combined in plantarflexion |
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where are the attachments of the calcaneofibular ligament? |
- apex of lateral malleolus to lateral surface of calcaneus |
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what is purpose of calcaneofibular ligament? |
resists inversion, especially with dorsiflexion |
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what are the attachments of the posterior talofibular ligament? |
post medial side of lateral malleolus and lateral tubercle of talus |
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what is primary function of post. talofibular lig? |
stabilize talus within the mortise |
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what does post. talofibular lig. limit? |
abduction of talus, specifically with dorsiflexion |
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where is the axis of rotation of the talocrural joint? |
through the body of talus and tip of both malleoli |
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what is the direction of the talocrural ligament? |
10 degrees superior 6 degrees anterior |
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what motions does the talocrural joint produce? |
- pronation/supination by definition, but main components are PF/DF |
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how many degrees of freedom does talocrural joint have? |
one - diagonal axis |
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what is neutral position of talocrural ligament |
90 degrees from leg |
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normal range of dorsiflexion (Talocrural) |
15-25° |
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normal range of plantarflexion (Talocrural) |
40-55° |
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arthrokinematics of open chain dorsiflexion at talocrural joint? |
talus rolls anterior (relative to leg) and slides posterior |
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what is taut is dorsiflexion |
calcaneofibular ligament |
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what is arthrokinematics of open chain PF at talocrural joint? |
talus rolls posterior and slide anterior |
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what is taut in PF |
ATFL |
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what are the facets of the subtalar joint? |
- posterior facet - middle facet - anterior facet |
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what is the prominent facet of the subtalar joint? |
posterior |
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what are the surfaces of posterior facet of subtalar joint? |
talus - concave calcaneus - convex |
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what are the surfaces of middle and ant. facets of subtalar? |
flat surface |
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what are the arthrokinematics of the subtalar joint? |
- lateral glide for eversion - medial glide for inversion |
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what is the axis of rotation for the subtalar joint? |
lateral post. heel and through subtalar joint in ant./medial/superior manner |
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what components of supination/pronation happen at subtalar joint? |
-inversion/eversion - abduction/adduction |
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Ratio of AROM inversion:eversion |
2:1 |
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ratio of PROM inversion:eversion |
3:1 |
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what is the purpose of the transverse tarsal joint? |
adapt to uneven surfaces - specifically the talonavicular |
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what are the surfaces of the talonavicular joint/ |
talus - convex navicular - concave |
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what is the importance of the spring ligament at the talonavicular joint? |
forms the floor and medial wall of the joint |
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what are the surfaces of the calcaneocuboid joint? |
each surface has convex and concave surface to form interlocking wedge that resists sliding |
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what is purpose of calcaneocuboid joint? |
provide stability to lateral foot |
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what are the axis of rotation of the transverse tarsal joint? |
- longitudinal - oblique |
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what is the motion of the longitudinal axis of the transverse tarsal joint? |
inversion/eversion |
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what are the motions of the oblique axis of the transverse tarsal joint? |
- abduction and dorsiflexion - adduction and plantarflexion |
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what is the purpose of the distal intertarsal joints? |
- provide stability across midfoot by forming transverse arch of foot - assist transverse tarsal joint with pronation/supination |
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what are the tarsometatarsal joints commonly known as? |
Lisfranc's joint |
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what do the TMT joints do? |
- separate midfoot from forefoot |
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what are the surfaces of the metatarsaophalangeal joints? |
MT - convex prox. phalanx - concave |
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where are the MTP joints located?
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2.5 cm proximal to web spaces of toes |
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what is unique about the movement of the big toe? |
it has 85° of extension (for gait), roughly 20° more than all other toes |
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what is the reference digit of the abduction/adduction of MTP joints |
the 2nd toe |
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what innervates anterior compartment muscles? |
deep branch of fibular n. |
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what are the muscles of ant. compartment? |
- tib anterior - EDL - EHL - fibularis tertius - EDB |
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what innervates the lateral compartment muscles? |
superficial branch fibular n. |
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what are the muscles of the Lateral compartment of the leg? |
- fibularis longus - Fibularis brevis |
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what innervates the posterior compartment of leg muscles? |
tibial n. |
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what are the superficial muscles of post. compartment? |
- gastroc - soleus - plantaris |
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what are the deep muscles of post. compartment |
- tib post. - FHL - FDL |
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what are the pretibial muscles |
- tib ant - EHL - EDL - Fib tertius |
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what is the action of the pretibial muscles? |
dorsiflexion |
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when are the pretibial muscles most active during gait? |
early stance preswing |
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why are pretibials active during early stance? |
to control rate of PF (eccentric) |
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why are pretibials active during preswing? |
to clear foot and toes (concentric) |
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what is required to DF foot in near sagittal plane? |
balanced contraction of pretibials |
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what is the role of the lateral compartment muscles |
evertors |
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what is the role of the superficial posterior compartment muscles? |
plantarflex |
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what is the role of the deep group of posterior compartment muscles? |
invertors |
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what structures run through the tarsal tunnel? |
- tib posterior - FDL - tibial neurovascular bundle |
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what is the role of the tibialis posterior? |
support medial longitudinal arch |
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what are the results of an overstressed or ruptured tib posterior |
collapse of medial longitudinal arch |
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what is the oddball of the intrinsic muscles? why? |
extensory digitorum brevis - it is on the dorsum of the foot and innervated by the deep fibular nerve |
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what is the purpose of the intrinsic muscles of the foot? |
- assist with standing/walking balance - provide structural stability for foot and medial longitudinal arch during push off phase |
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what are the motions of the talocrural joint during gait? |
- dorsiflexion immediately after initial contact - progressive dorsiflexion after foot flat until heel off phase |
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when is the talocrural joint most stable during gait? why? |
- becomes more progressively stable until max stability at end phase - because the wider ant. part of talus wedges into the tibiofibular component of mortise |
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where is the tension during the progressive dorsiflexion of gait?
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- achilles tendon - fibularis longus - calcaneofibular ligament |
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what is the primary load bearing and shock absorbing structure of the foot? |
- medial longitudinal arch |
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what forms the medial longitudinal arch? |
- calcaneus - talus - navicular - cuneiforms - 3 medial metatarsals |
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when do muscle forces assist the arch? |
when stresses and loads are larger and more dynamic than just body weight: - standing on toes - walking - jumping - running |
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what is the keystone of the medial long. arch? |
- talonavicular joint and connective tissues associated |
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what are the non-muscular structures that maintain the height/shape of medial long. arch? |
- plantar fascia - spring ligament - first TMT joint |
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what issues arise if plantar fascia is stretched?
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- support requires muscle use that will increases chance of overuse syndromes |
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what is pes planus? |
flat foot, often due to joint laxity in midfoot/prox. forefoot regions with overstretched plantar fascia/spring ligament/tib. posterior tendon |
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what happens during stance phase of gait in pt. with pes planus? |
- subtalar joint will pronate - rearfoot adopts a valgus posture |
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Rigid pes planus characteristics? |
- structural - arch dropped even in NWB - normally congenital |
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Flexible pes planus characteristics |
- more common - normal arch in NWB - excessively drops in WB |
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what is often associated with flexible pes planus? |
- tibialis posterior tendon dysfunction* - increased laxity of local connective tissues - structural abnormalities - compensatory mechanisms |
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what is normal compensation pattern of pes planus? |
- rear foot everts - midfoot/forefoot supinate to keep lateral border of foot on the ground |
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what causes the rearfoot eversion in pes planus? |
- talus moves medially, moving calcaneus lateral - tibia IR creating a genu valgum posture |
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where is pain normally present in pes planus (Besides foot)? why? |
medial knee - because of the genu valgum |
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what is Hallux limitus (hallux rigidis)? |
- post traumatic condition that limits motion to 55° extension |
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what are the symptoms of Hallus limitus? |
- decreased motion - articular degeneration - pain at 1st MTP joint |
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what is normally the mechanism of injury for hallux limitus |
forced hyperextension (turf toe) |
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what is hallux valgus (bunion) |
- progressive lateral deviation of great toe with respect to midline of the body - 1st MTP adducts in respect to the body |
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what can happen in extreme hallux valgus? |
- lateral dislocation of the MTP joint
- exposes metatarsal head as a lump and becomes painful and inflammed |
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what is the windlass effect? |
during WB plantarflexion the extension of MTP joints stretch the plantar fascia, which raises the arch (normal) |
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what happens when someone with pes planus WB plantarflexes? |
forefoot sags with load of BW during attempt to stand on tip toes |
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how does pes planus effect the windlass effect? |
reduced ext. of the MTP joints limits the usefulness of windlass effect |
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issues with pes planus in WB plantarflexion |
takes more work to produce power required for motion |
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NWB rearfoot motions of supination |
- Calcaneus inversion - calcaneus adduction - calcaneus PF |
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NWB rearfoot motions of pronation |
- calcaneus eversion - calcaneus abduction - calcaneus DF |
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WB rearfoot motions of supination |
- Calcaneus inversion (varus) - talus abduction (LR) - talar DF - tibfib lateral rotation |
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WB rearfoot motions of pronation |
- calcaneus eversion (valgus) - talus adduction (MR) - talus PF - tibfib medial rotation |
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what is the ROM of knee during gait?
|
0-60° |
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what is the role of the knee during loading response and midstance |
shock absorption |
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what is the role of the knee during initial swing? |
foot clearance (knee flexion is more important than DF) |
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when are knee extensors active during gait? |
heel contact and shortly after heel contact |
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when are knee extensors most active during gait? |
after heel contact
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what roles do the knee extensors (quads) have in gait? |
- eccentrically control knee flexion - concentrically extend knee - crucial for shock absorption |
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what is the role of the glute max during gait? |
knee extensor via the IT band insertion |
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how does the glut max work as a knee extensor? |
activates and creates tension in IT band and resists knee flexion and contributes to extension |
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when is the glute max active during gait? |
late terminal swing to mid-midstance |
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what is role of hamstrings during gait? |
- eccentrically decelerate knee extension before intial contact - assist with hip ext. and improve stablity |
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what is responsible for knee flexion in swing?
|
momentum |
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knee posture during initial contact? |
- full extension |
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knee function during initial contact? |
WB stability |
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what controls the knee during initial contact? |
- HS prevent hyperextension - Glute max activates |
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what is knee posture during loading response?
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- 15-20° flexion |
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what is function of knee during loading response? |
- shock absorption - stability |
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what causes knee flexion during loading response? |
- heel rocker moves tibia fwd faster than femur advances |
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what limits knee flexion during loading response? |
eccentric quad contraction |
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what stops the eccentric quad contraction during loading response? |
biceps femoris long head |
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what supports knee during loading response? |
IT band provides lateral support |
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what is posture of knee during midstance? |
knee extension |
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what is function of knee during midstance |
stability during weight bearing |
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what is the posture of the knee during terminal stance |
max extension |
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what is function of the knee during terminal stane |
- stable WB - maximize step length |
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what happens to knee after max ext. is reached in terminal stance? |
almost immediately reversed to knee flexion due to forefoot rocker |
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what happens to knee as terminal stance progresses (3 steps) |
- post. thigh muscles intiate flexion - tibia IR to unlock knee - knee flexed 10° by end of terminal stance |
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what is the posture of the knee in preswing? |
knee flexion (40°) |
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what is the function of the knee in preswing? |
- prepare for swing |
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what is the posture of knee during initial swing? |
- flexion (60° - most flexion in gait) |
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what is the function of knee during initial swing? |
foot clearance |
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what muscles are active during initial swing? |
- biceps femoris short head - sartorious - gracilis |
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what is the motion of the knee in midswing? |
passive knee extension |
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what is the function of the knee in midswing? |
advance limb |
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what causes knee extension in midswing? |
momentum of hip flexion |
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what is the motion of the knee during terminal swing? |
knee extension |
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what is the function of the knee during terminal swing? |
- limb advancement
- stance preparation |
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how does a quad avoidance gait present? |
- fwd flex trunk during stance - strong ankle plantar flex - may use hand to extend knee |
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what role does the IT band play in quad avoidance gait? |
maintains knee ext. |
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what will cause pt. to use quad avoidance gait? |
- 3rd degree muscle strain - femoral n. neuropathy |
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what is the foot support pattern during Initial contacT? |
Heel support to foot flat during loading response |
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what are the characteristics of foot support during loading response? |
- 5th met head normally 1st forefoot contact - foot flat ends at midstance |
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what is the foot support pattern at terminal stance/preswing? |
forefoot support as heel rises |
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what are the arc of motion in stance phase and what is their purpose? |
- PF > DF > PF - for limb progression |
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what is the arc of motion during swing phase? |
DF for foot clearance |
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what is the ankle ROM during gait? |
about 25° (10° DF - 15° PF) |
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when are plantarflexors active during gait? |
- consistently active during stance |
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when are dorsiflexors active during gait? |
- Initial contact - Loading response - swing |
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what are the dorsiflexors role during initial contact and loading response? |
- the eccentrically contract to decelerate PF |
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what are the dorsiflexors role during swing phase? |
concentrically contract for foot control |
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what is the motion of the subtalar joint during gait? |
- neutral in initial contact - everts 5° in loading response - eversion decreases to 2° at end of single leg stance - neutral in swing |
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what should be seen at the midtarsal joint during gait? |
- decrease in medial long. arch in midstance - arch restored during heel rise |
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why does the medial long. arch restore during heel rise? |
windlass effect |
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what is the posture of the 1st MTP in preswin |
55° DF |
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posture of foot/ankle at initial contact |
neutral |
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what is the function of the foot/ankle during initial contact? |
- initial heel rocker - impact deceleration |
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what is the posture of the ankle during loading response? |
- ankle PF - subtalar eversion - arch flattens |
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what is the function of the foot/ankle during loading response? |
- heel rocker initiation of progression - ankle axis realignment |
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what is the motion of the foot/ankle during midstance? |
- 1st arc of single leg stance DF - MT joint DF |
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what is the function of the foot/ankle during midstance? |
- ankle rocker progression - MT shock absorption |
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what happens to the tibia during midstance? |
moves from 5° PF > 5° DF |
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what is the role of gastroc/soleus during midstance/terminal stance?
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eccentrically control progression |
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what is the motion of the foot/ankle during terminal stance? |
- heel rise - ankle DF - less subtalar eversion to lock MT joint |
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what is the function of the foot/ankle during terminal stance? |
forefoot rocker |
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what is the motion of foot/ankle during preswing?
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- 2nd arc ankle PF - knee flexion for swing |
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what is the function of the foot/ankle during preswing? |
- propulsion - toe rocker advances limb |
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what is the motion of the foot/ankle during preswing? |
- 10° DF > 15° PF (max PF) |
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what is the motion of the foot/ankle during initial swing? |
2nd arc of DF |
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what is the function of the foot/ankle during initial swing? |
foot clearance |
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what is the ROM of foot/ankle during initial swing? |
15° PF > neutral |
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what is the motion of the foot/ankle at midswing? |
continued ankle DF |
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what is the function of the foot/ankle at midswing? |
foot clearance |
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what is the motion of foot/ankle at terminal swing? |
- support of neutral ankle |
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what is the function of the foot/ankle at terminal swing? |
prepare for initial contact |
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what is plantarflexor gait? |
- calf muscles fire early during swing - pt. lands toe first - disrupts the 2nd rocker w/ PF instead of DF |
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what is steppage gait?
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- dorsiflexors are paralyzed requiring excessive hip/knee flexion - causes foot slap (AKA foot drop) |
