Bones of the Lower Limb

BONES OF THE LOWER LIMB

Kaan Yücel M.D., Ph.D 16.January.2014 Thursday

The Dance Hall by Vincent van Gogh ,1888

2 functional components: Pelvic girdle & bones of the free lower limb

Body weight is transferred Vertebral column (Sacroiliac joints)

Pelvic girdle (Hip joints)

Femurs (L. femora)

Skeleton of the lower limb (inferior appendicular skeleton)

3

longest and heaviest bone

Transmits body weight from the hip bone to the tibia.

FEMUR

Shaft (Body)

Superior / Proximal end

Inferior/ Distal end

Superior (proximal) end of the femur Proximal end of femur

HeadNeck 2 trochanters

Greater & Lesser

intertrochanteric lineintertrochanteric crest quadrate tuberclefovea capitis for lig.teres

Superior (proximal) end of the femur Shaft of femur

Gluteal tuberosityLinea asperaMedial and lateral lips of linea asperaMedial and lateral supracondylar linesPectineal line

Superior (proximal) end of the femur Distal end of femur

Adductor tubercleIntercondylar fossaMedial and lateral condylesMedial and lateral epicondylesMedial and lateral femoral condylesPatellar surface

Located on the anteromedial side of the legSecond largest bone in the body Flares outward at both ends to provide an increased area for articulation and

weight transfer.

TIBIA

Proximal end of tibiawidens to form medial & lateral condyles (1,2) flat superior articular surface tibial plateau (3)articular surfaces separated by intercondylar eminence (4) formed by 2 intercondylar tuberclesmedial and lateral (5,6)flanked by relatively rough anterior and posterior intercondylar areas (7,8)

Anterolateral view of left tibia

2

1 456

Shaft of tibia

medial malleolus

Interosseous membrane unites the two leg bones.

Inferiorly, the sharp border is replaced by fibular notch.

Distal end of tibia

Largest sesamoid bone (a bone formed within the tendon of a muscle) in the body and is formed within the tendon of the quadriceps femoris muscle as it crosses anterior to the knee joint to insert on the tibia. The patella is triangular:

Apex is pointed inferiorly for attachment to the patellar ligament, which connects the patella to the tibia.Base is broad and thick for the attachment of the quadriceps femoris muscle from above.Posterior surface articulates with the femur and has medial and lateral facets, lateral facet is larger than the medial facet for articulation with the larger corresponding surface on the lateral condyle of the femur.

PATELLA (Knee cap)

Slender, lies posterolateral to the tibia No function in weight-bearing.Serves mainly for muscle attachment

FIBULA

Head (& a pointed apex) Articulates with the fibular facet on the posterolateral, inferior aspect of the lateral tibial condyle.Neck

Like the shaft of the tibia,

3 borders (anterior, interosseous, & posterior) 3 surfaces(medial, posterior, and lateral)

Proximal end & shaft of fibula

Distal end of fibula

Distal end enlarges, projects laterally & inferiorly lateral malleolus

more prominent and posterior than the medial malleolus extends approximately 1 cm more distally.

Tarsus (n=7) Metatarsus (n=5) Phalanges (n=14)

BONES OF FOOT

"flat surface, especially for drying,"Posterior foot/Proximal foot/Hindfoot

TARSUS

7 bonesTalusCalcaneusCuboidNavicularThree cuneiforms

Only one bone, the talus, articulates with the leg bones.

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HeadNeckBody

Superior surface trochlea of the talus is gripped by the two malleoli and receives the weight of the body from the tibia.

TALUS(L., ankle bone)

Talus transmits weight in turn, dividing it between the calcaneus, on which the body of talus rests, and the forefoot, via an osseoligamentous “hammock”

Hammock (Spring ligament;Calcenonavicular ligament) Across a gap between sustentaculum tali and navicular bone, lies anteriorly.

Largest and strongest bone in the foot Lateral surface of the calcaneus has fibular trochleaSustentaculum tali shelf-like support of the head of the talus

Calcaneus(L., heel bone)

24

Flattened, boat-shaped bone Between head of the talus posteriorly & 3 cuneiforms anteriorlyMedial surface projects inferiorly to form, navicular tuberosity

Most lateral bone in the distal row of the tarsus

Navicular(L., little ship)

Cuboid

Medial (1st)Intermediate (2nd)Lateral (3rd)

Each cuneiform articulates with navicular posteriorly & base of its appropriate metatarsal anteriorly.

Lateral cuneiform also articulates with the cuboid.

Three cuneiform bones(L. cuneus, wedge shaped)

5 metatarsals numbered from the medial side of the foot

Metatarsals and phalanges located in anterior half (forefoot)

Tarsals in the posterior half (hindfoot)

METATARSUS (Anterior foot/distal foot)

14 phalanges 1st digit (great toe) 2 phalanges(proximal and distal) Other four digits 3 phalanges (proximal, middle, and distal)