Unit 6, Leg + foot

Tibiofibular Joints how many? Can they move independently from each other?

2 joints: tibiofibular joint (proximal) & tibiofibular syndesmosis (inferior tibiofibular joint) interosseous membrane joins shaft of 2 bones all fibers run inferiorly from tibia to fibula ->resist downward pull by muscles movement at superior joint is impossible without movement at inferior syndesmosis!

anterior cruciate ligament (ACL) posterior cruciate ligament (PCL) Differences? what movements do they limit?

Anterior cruciate ligament: weaker, from anterior intercondylar area of tibia to medial part of lateral condyle of femur limits posterior rolling of femoral condyles on plateau Posterior cruciate ligament: Stronger, from posterior intercondylar area of tibia to anterior part of lateral surface of medial condyle of femur Limits anterior rolling & prevents anterior displacement of femur on tibia & prevents hyperflexion of joint

Tubercle placed on anterolateral aspect of lateral tibia condyle, inferior to articular surface

Anterolateral tibial tubercle (Gerdy tubercle

each metatarsal has what 3 things?

Base - large proximal end, articulates with cuniforme (1, 2 and 3) and cuboid (4 and 5) Shaft Head

replaces sharp interosseous border inferiorly; fibrous attachment for distal end fibula?

Fibular notch

oblique ridge on lateral surface of calcaneus, anchors tendon?

Fibular trochlea

transverse arch of foot

From side to side By cuboid, cuneiforms and base of metatarsals

Ankle Joint

Hinge type synovial joint, between distal ends of tibia & fibula and superior part of talus

Tibia articulates with talus in 2 places?

Inferior surface forms roof of malleolar mortise, transferring bodies weight to talus Medial malleolus articulates with medial surface of talus

The only hinge Synovial Joint of the foot? Do you remember its ligaments?

Interphalangeal Joints: Hinge Synovial Joint (Flexion/ Extension) Collateral and plantar ligaments

Articulation surfaces of knee? (3)

Lateral and medial femorotibial articulation Between lateral and medial condyles of femur and tibia Femoropatellar articulation Between patella and femur NB! Fibula is not involved in this articulation

form outer wall of rectangular socket (mortise), = superior component of ankle joint

Lateral malleolus of fibula

Differences between left/right meniscus?

Medial meniscus: c-shaped, anterior end (horn) attached to to anterior intercondylar area of tibia; posterior end to posterior intercondylar area of tibia; less mobile than lateral meniscus Lateral meniscus: nearly circular, smaller & more freely moveable

lateral longitudinal arch of the foot

Much flatter & rests on ground while standing Made of calcaneus, cuboid & lateral two metatarsals

Flattened, boat shaped bone, located between head of talus posteriorly & 3 cuneiform bones anteriorly

Navicular

Vascular groove on Tibia, distal to soleal line, for passage of main artery supplying proximal end of bone? Is it posteriorly of anteriorly?

Nutrient foramen Posteriorly!

On tibia there is a diagonal ridge, on posterior surface, runs inferomedially to medial border?

Soleal line

plantar aponeurosis is?

Strong, dense, connective tissue. Originates at calcaneus, attaches phalanges. Calcium may deposit along stress lines from chronic irritation causing a heel spur support arches of foot

only bone that articulates with leg bones & only tarsal bone that has no muscular/ tendinous attachment

Talus (ankle bone):

articular surfaces of the knee are most congruent when?

The knee is most congruent in erect position (upright)

Tuberosity of cuboid what groove can we find on cuboid?

Tuberosity of cuboid: posterior laterally Groove for tendon of fibularis (peroneus) longus muscle: anterior to tuberosity

subtalar joint?

a joint in the ankle found between the talus and calcaneus

intracapsular ligaments of the knee Where are they in the joint capsule?

anterior cruciate ligament (ACL) posterior cruciate ligament (PCL) Crisscross within joint capsule but outside synovial cavity (bc of synovial fold);

fibular articular facet of tibia is where?

articulation site for head of fibula under lateral condyle

Tibial tuberosity: is placed where? Gives attachment for what ligament?

at superior end of anterior border patellar ligament

Coronary ligaments on the knee is attached where? Ligament on anterior edge of menisci crossing intercondylar area?

between menisci & periphery of tibial condyles Transverse ligament

talus bone consist of?

body, head & neck, posterior process

Tarsal Tunnel?

covered with thick ligament: flexor retinaculum protects arteries, veins & nerves inside tunnel tibial nerve leaves posterior compartment of leg by passing deep to flexor retinaculum bt medial malleolus and calcaneus (narrow space inside ankle) compression of tibial nerve (tarsal tunnel syndrome) occurs when there is edema and tightness in ankle involving the synovial sheats of the tendons of muscles in posterior compartment of the leg

Matatarsus are Numbered how?

from the medial side of the foot

The posterior process of talus has a Lateral and medial tubercle with ___________ in between?

groove for tendon of flexor hallucis longus

Medial intercondylar tubercle Lateral intercondylar tubercle These tubercles fit into __________ between femur condyles

intercondylar fossa

largest & most superficial joint? What type of joint is this? What kind of movement does it allow

knee combination of hinge type of synovial joint & pivot joint flexion/extension & gliding/ rolling & rotation about a vertical axis

Base of which metatarsals have tuberosities that provides attachments for ligaments and muscles?

lateral and medial (1st and 5th) Tuberosity of 5th metatarsal projects over cuboid

tibia plateau is formed by? Which facet is concave, which is convex?

medial & lateral condyles Medial facet (slightly concave) Lateral facet (slightly convex)

patellar ligament receives medial & lateral ________ (from vastus lateralis muscle)?

medial & lateral patellar retinaculum

Locking mechanism (passive) of knee: when knee is fully extended with foot on ground the knee passively locks bc of_____________?

medial rotation of femoral condyles on tibia plateau

talocalcaneal ligaments of talocalcaneal joint?

medial, lateral, posterior & interosseous talocalcaneal ligaments

medial & lateral sesamoid bones are found on which metatarsal?

on plantar surface on head of 1st metatarsal (embedded in tendons)

Extra-capsular/Intrinsic Ligaments of knee joint?

patellar ligament, fibular collateral ligament, tibial collateral ligament, oblique popliteal ligament (photo) & arcuate popliteal ligament

Tibiofibular Joint: superior joint What ligaments strengthen it? What movements can it do?

plane type of synovial joint between flat facet of fibular head & articular facet posterolaterally on lateral tibial condyle tense joint capsule surrounds joint &attaches to margins of articular surfaces; strengthened by anterior & posterior ligaments of fibular head (superomedially from fibular head to lateral tibial condyle) Movement: slight movement during dorsiflexion of foot

Unlocking mechanism (active): to unlock knee, _______ contracts, rotating femur laterally about 5° on tibial plateau so flexion of knee can occur

popliteus

Why is the knee prone to injury? (weak) Staibility depends on? Most important muscle in stabilising?

relatively weak mechanically bc incongruence of its articular surfaces stability of knee joint depends on: 1.) strength & action of surrounding muscles 2.) ligaments that connect tibia & femur most important muscle in stabilizing: large quadriceps femoris

Patella is what type of bone?

sesamoid bone also known as the kneecap, is a flat, circular-triangular bone which articulates with the femur (thigh bone) and covers and protects the anterior articular surface of the knee joint.

Maintenance of Arches of the Foot (passive factors)?

shape of united bones 4 layers of fibrous tissue that bowstring longitudinal arch 1.) plantar aponeurosis 2.) long plantar ligament 3.) plantar calaneocuboid (short plantar) ligament 4.) plantar calcaneonavicular (spring) ligament

sustentaculum tali of calcaneus? articulates with what?

shelf-like projection on the superior medial aspect - articulates with the talus superiorly

Calcaneus Articulates with ________on the superoanterior surface, and with _______ on the anterior surface

talus cuboid

7 tarsal bones of the foot

talus, calcaneus, cuboid, navicular and 3 cuneiforme

Bones of foot:

tarsus, metatarsus and phalanges; 7 tarsal bones, 5 metatarsal bones & 14 phalanges

second largest bone in body

tibia

Fibula is attached to tibia by what?

tibiofibular joint & tibiofibular syndesmosis (which includes interosseous membrane)

Part of talus that receives weight of body from tibia

trochlea of talus

Calcaneal tuberosity? What part of it contacts ground when standing?

weight bearing prominence on posterior part Medial, lateral & anterior tubercles (only medial contacts ground when standing)

What joints of the foot are plain synovial joints? (5)

- Calcaneocuboid: plane synovial joint (inversion/ eversion, circumduction) - Subtalar: plane synovial joint (inversion & eversion of foot) - Cuneonavicular joint (little movement) - Tarsometatarsal joints: (gliding or sliding) - Intermetatarsal Joints: plane synovial joint (little individual movement occurs)

Maintenance of Arches of foot (DYNAMIC factors)?

- active reflective action of intrinsic muscles of foot (long arch) - active & tonic contraction of muscles with long tendons extending into foot: flexor hallucos & digitorum longus, fibularis longus & tibialis posterior

joint capsule of knee joint attaches where?

-Fibrous layer: attaches to femur superiorly, proximal to articular margins of condyles posteriorly encloses condyles & intercondylar fossa gap/ opening posterior to lateral tibial condyle for tendons of popliteus inferior: attaches to margins of tibial plateau anterior: quadriceps tendon, patella & patellar ligament replace fibrous layer -Synovial layer: lines all internal articular surfaces that are not covered with articular cartilage Attached to periphery of the articular cartilage covering femoral & tibial condyles, posterior surface of patella & edges of menisci Posterior: into intercondylar region covering cruciate ligament & infrapatellar fat pad -> infrapatellar synovial folds lateral & medial alar folds: cover inner surface of fat pads Communication with: Suprapatellar (synovial) bursa(superior to patella)

medial collateral ligament of ankle (deltoid ligament): these prevent what?

1.) tibionavicular part 2.) tibiocalcaneal part (to sustentaculum tali) 3.) anterior tibiotalar part (to neck of talus) 4.) posterior tibiotalar part (to tubercles of talus) Stabilise ankle during eversion, prevent subluxation (partial dislocation)

Longest metatarsal?

2nd

Borders and surfaces of fibula?

3 borders: anterior, interosseous & posterior border 3 surfaces: medial, lateral & posterior surface

Borders and surfaces of tibia? (3 of each)

3 surfaces: lateral, medial & posterior; 3 borders: anterior, medial, interosseous

Anterior & posterior intercondylar areas of tibia gives attachment to?

Attachment for menisci & principal ligament of knee (crucicate ligaments!) which holds femur & tibia together

Largest and strongest bone in the foot Transmits majority of the weight to the ground

Calcaneus

most lateral bone in distal row of tarsus?

Cuboid bone

How much can the knee flex?

Flexion: 120° (hip extended) 140° (hip flexed) 160° passively; by hamstrings

Transverse tarsal joint consist of which 2 joints?

Formed by 2 separate joints aligned transversely: 1.) Talonavicular part of talocalcaneonavicular joint 2.) calcaneocuboid joint midfoot & forefoot rotate as a unit on hindfoot around a longitudinal (AP) axis

Evolution of upright posture What are some important changes?

Humans: Longer attachment of neck muscles - the head rotates independently of the body Wider attachment of the gluteal muscles - the legs and and trunk move together More developed tendons of the foreleg muscles absorb and release muscle energy during running Important changes: primates: m. gluteus medius and m. gluteus minimus are extensors of the hip man: m. gluteus medius is abductor of the upper leg

What separates the superior articular surfaces of tibia? What can we find on each side of that separation?

Intercondylar eminence: separates articular surfaces Medial intercondylar tubercle Lateral intercondylar tubercle

What is special about talocalcaneonavicular joint? What movement does it do? What ligament supports the head of talus?

It is a synovial joint, however talo-navicular part is ball and socket type (gliding & rotatory movement) Plantar calcaneonavicular (spring) ligament

Anserine bursa location?

Located on proximomedial aspect of tibia between superficial MCL and hamstring tendons.

Which cuneiform bone is the largest? which one is the smallest? what do they all articulate with?

Medial (1st) =largest, intermediate (2nd) = smallest, lateral (3rd) Each cuneiforme articulates with naviculare posteriorly & base of metatarsale anteriorly Lateral also articulates with cuboid

How much can the knee rotate medially/laterally?¨How much can it extend?

Medial rotation: 10° with knee flexed, 5° with knee extended by semitendinousus (muscle) Lateral rotation: 30° by biceps femoris Extension: to 0°, by quadriceps femoris

Naviculare tuberosity: Where is it located? What is its function? Why is it important?

On the medial surface, function as tendon attachment bc medial border does not rest on ground BUT forms medial longitudinal arch of foot (which must be supported centrally)

Medial longitudinal arch of foot? What parts does it consist of?

Primary load bearing & shock-absorbing structure of the foot Height of arch is maintained by plantar fascia, intrinsic foot muscles, spring ligament and stability of midfoot joints composed of calcaneus, talus, navicular, 3 cuneiforme & 3 metatarsale talar head is keystone

Movement of Menisci:

Rolling movement of femoral condyles during flexion/extension

Bursa of knee joint

Subcutaneous prepatellar Overlies the patella, covering its surface Subcutaneous infrapatellar Inferior to patella, between skin and tibial tuberosity 4 bursas communicate with synovial cavity of the knee joint Suprapatellar bursa Between femur and tendon of quadriceps Popliteus bursa Between tendon of poplitea (posterior) and lateral condyle of tibia Anserine bursa Between tendon of (sartorius, gracillis and semitendinosius) and (tibia and tibial collateral ligament) posteriorly Gastrocnemius bursa Superior to anserine bursa, and deep to proximal attachment of tendon of medial head of gastrocnemius Semimembranosus bursa Between medial head of gastrocnemius and Semimembranosus tendon Deep infrapatellar bursa Between patellar ligament and anterior surface of tibia

At ankle: weight transferred to which bone first?

Talus

Movements of the ankle

dorsiflexion, plantar flexion, inversion, eversion

Tibiofibular Syndesmosis (distal joint) Ligaments? Articulation?

inferior fibrous attachment of tibia and fibula that prohibits movement between the two bones Articular Surfaces & Ligaments: -Rough triangular articular area on medial surface of inferior end of fibula with facet on inferior end of tibia -Interosseous tibiofibular ligament: connection bt tibia &fibular -Anterior & posterior tibiofibular ligament: -Inferior transverse (tibiofibular) ligament: distal deep continuation of posterior tibiofibular ligament

medial malleolus of tibia articulate w what bone?

medial process on distal end, forms medial bump of ankle articulate with talus

lateral collateral ligament of the ankle consist of what ligaments?

reinforces the ankle joint laterally; limits inversion of the rearfoot; consists of 3 separate parts 1.) anterior talofibular ligament: flat, weak, extends anteromedially from lateral malleolus to neck of talus 2.) posterior talofibular ligament: thick, strong, runs horizontally medially form malleolar fossa to lateral tubercle of talus 3.) calcaneofibular ligament: round cord that posteroinferiorly from lateral malleolus to lateral surface of calcaneus

sesamoid bones are?

small, round bone embedded in a tendon; protects the tendon from compressive forces

Tarsometatarsal joint forms what line?

tarsometatarsal line