Ch. 8 Lower Limb and Foot Flashcards Preview

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Flashcards in Ch. 8 Lower Limb and Foot Deck (27)

Skeleton of Upper Limb

- skeleton of lower limb consists of 2 separate regions: pelvic girdle and free part
- lower limbs are stronger and larger than upper limb bones



femur: longest, heaviest and strongest bone in body
- proximally, head articulates with acetabulum of hip bone forming the coxal joint
- neck: distal to head, common site of fracture
- greater and lesser trochanters: projections that servse as point of attachment for tendons and some of thigh and buttock muscles
- distally, medial and lateral condyles articulate with condyles of tibia forming knee joint
- articulates with patella
- gluteal tuberosity and linea aspera: attachment sites for large hip muscles
- intercondylar fossa: depression between the condyles
- medial and lateral epicondyles: muscle site attachments for knee muscles



- largest sesamoid bone of body
- forms patellofemoral joint
- superior surface in base
- inferior, narrower surface is the apex
- thick articular cartilage lines the posterior surface
- increases the leverage of the quadriceps femoris muscle
- patellofemoral stress syndrome: runner's knee


Tibia (shin bone)

- larger, medial weight bearing bone of leg
- lateral and medial condyles at proximal end articulate with femur
- articulates distally with talus and fibula
- tibial tuberosity: attachment site for patellar ligament
- medial malleolus: medial surface of distal end (medial surface of ankle joint)



- smaller, laterally placed bone of leg
- non-weight bearing
- head forms the proximal tibiofibular joint
- lateral malleolus: distal end, articulates with the tibia and the talus at the ankle


Foot: Tarsal, Metatarsals, and Phalanges

- tarsus 7 bones
- metatarsals 5 bones
- phalanges 14 bones



- articulates with tibia and fibula
- calcaneus is heel bone, largest and strongest tarsal bone
- navicular, cuboid, and 3 cuneiforms


Arches of Foot

2 arches support weight of body
- provide spring and leverage to foot when walking
- arches flex when body weight is applied
- flatfoot: arches decrease or fall
- clawfoot: too much arch occurs due to various pathologies
medial longitudinal arch: extends from heel to the big toe
lateral longitudinal arch: not as high as medial longitudinal arch
transverse arch: runs perpendicular to longitudinal arches


Thigh Muscles the Move Knee Joint

- mainly originate from pelvic girdle and thigh
1. anterior extensor muscles- quadriceps femoris group: rectus femoris, vastus lateralis, vastus medialis, vastus intermedius
2. posterior flexor muscles- hamstrings femoris group: biceps femoris, semimembraneous, semitendinosus
3. medial femoris muscles: gracilis


Anterior Extensor Muscles

1. rectus femoris: anterior inferior illiac spine; tibiual tuberosity
2. Vastus lateralis: greater trochnater and line aspera of femur; tibital tuberosity
3. vastus medialis: linea aspera of femur; tibial tuberosity
4. Vastus intermedius: anterior and lateral surface of body of femur; tibial tuberosity
- all 4 extend leg at knee joint and flex thigh at hip


Posterior Flexor Muscles

1. biceps femoris: long head from ischial tuberosity and short head from line aspera of femur; head and lateral condyle of fibiula
2. Semimembranosus: ischial tuberosity; medial condyle of tibia
3. Semitendinosus: ischial tuberosity; shaft of tibis
- posterior group of muscles commonly flexes the leg at knee joint and extend the thigh at hip


Medial Femoris Muscle

Gracilis: body and inferior ramus of pubis; medial surface of bone of tibia
- adducts thigh at hip joint, rotate thigh medially, and flexes leg at knee joint


Leg Muscles (anterior, lateral and posterior)

anterior compartment:
- extensor hallicus longus
- tibialis anterior
- extensor digitorium ongus
lateral compartment:
- peroneus longus and brevis
posterior compartment:
1. superficial layer: gastrocnemius, soleus, plantaris
2. deep layer: flexor digitorium, flexor hallicus longus, tibilialis posterior, popliteus


Anterior Compartment

extensor halliucis longus: extends great toe and dorsiflexes foot at ankle joint
tibialis anterior: dorsiflexes and inverts foot
extensor digitorium longus: extends toes 2-5, dorsiflexes foot at ankle joint


Lateral Comparment

fibularis longus and brevis:
- both muscles everts foot and are weaker in flexing plantar


Posterior Compartment (superficial layer)

gastrocnemius: flexes leg at knee plantar flexes foot at ankle
soleus: plantar flexes foot at ankle
plantaris: weak leg flexor; plantaris flexes foot at ankle joint


Posterior Compartment (deep)

flexor digitorium longus: plantar flexes foot at ankle
flexor hallicus longus: plantar flexes foot at ankle joint
tibialis posterior: plantar flexes and inverts foot
popliteus: flexes leg, medially rotates tibia to unlock the knee


Intrinsic Muscles of the Foot

- termed intrinsic because they originate and insert within the foot
- limited designed for support and locomotion, are split into dorsal and plantar groups
- only one dorsal muscle which extends toes 2-5 at MTP joints
- plantar muscles are arranged in four layers with most superficial of these called first layer


Plantar Group Muscles (first layer)

1. flexor digitorum brevis: attaches to middle phalanges of toes, flexes toes 2-5 at IP and metatarsophalngeal joint
2. abductor hallucis: abducts and flexes the great toe
3. abductor digiti minimi: abducts and flexes the little toe


Second Layer

1. quadratus plantae: attach to tendons of digitorium longus to flex toeas 2-5
2. lumbricales muscles: attach to tendons of flexor digitorium longus
- serve to flex the MP joints
- extends toes 2-5 at interphalangeal joint


Third Layer

1. adductor hallucis: adducts and flexes great toe
2. flexor hallucis brevis: flexes great toe at MTP joint
3. flexor digiti minimi brevis: flexes little toe at MTP joint


Fourth Layer

Dorsal Interossei: adducts and flex toes 2-5 at MTP and extend toes at IP
Plantar interossei: adducts and flexes proximal MTP and extend toe at IP join


Nervous Supply: Sacral and Coccygeal Plexuses

- anterior rami of spinal nerves L4-5 and S1-4 form sacral plexus
- situated largely anterior to sacrum
- supplies nerves to buttocks, perineum, and lower limbs
- sciatic nerve arises from sacral plexus
- coccygeal nerves form small coccygeal plexus


Innervation of lower limb and foot

1. sacral plexus (l4-5, S1-4)- innervates: lowerback, pelvis, perineum, post. surface of thigh and leg, dorsum and plantar of foot
2. common fib. nerve- innervates anterior, lateral leg and dorsum of foot- superficial gluteal nerve, inferior gluteal nerve, nerve to piriformis, pudendal (s2-4)


Sciatic Nerve and Tibial

common fibular nerve- innervates anterior and lateral leg and dorsum of foot- also innervates: superficial gluteal region, inferior gluteal region, posterior femoral cutaneous, pudendal


Blood Flow to Lower Limb (arteries)

abdominal aorta- internal iliac artery- external illiac artery- femoral artery- popiteal artery- anterior and posterior tibial artery- fibular/peroneal artery-
- dorsalis pedis- digital arteries
- plantar arch


Blood Flow To Lower Limbs (veins)

anterior tibial and Posterior tibial- popiteal vein- deep femoral vein- great and small saphenous- veins- femoral vein- external iliac- internal iliac vein- common iliac vein- inferior vena cava