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Skeleton of the lower limb (inferior appendicular skeleton)
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)
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Longest and heaviest bone in the body.
Transmits body weight from the hip bone to the tibia.
Superior / Proximal end
Shaft (Body)
Inferior/ Distal end
Superior (proximal) end of the femur
Head
Neck
2 trochanters (Greater & Lesser)
The site where the neck & shaft join is indicated by
intertrochanteric line
A similar but smoother, more prominent ridge,
intertrochanteric crest joins the trochanters posteriorly.
The rounded elevation on the crest quadrate tubercle
Posteriorly a broad, rough line linea aspera
Superiorly, lateral lip blends with the broad
gluteal tuberosity
Prominent intermediate ridge pectineal line
between
central part of the linea aspera
&
base of the lesser trochanter
Inferiorly, linea aspera divides into
medial and lateral supracondylar lines
lead to
medial and lateral femoral condyles
make up nearly the entire distal end of femur
Separated posteriorly and inferiorly by
intercondylar fossa
Anteriorly merge to form
a shallow ldepression
patellar surface
Lateral surface of the lateral condyle has a central projection
Lateral epicondyle
Medial surface of the medial condyle has a larger and more prominent
Medial epicondyle
Superiorly another elevation
Adductor tubercle
TIBIA (Shin bone; Schenkel)
Located on the anteromedial side of the leg
Nearly parallel to the fibula,
Second largest bone in the body
It flares outward at both ends to provide an increased area
for articulation and weight transfer.
Proximal end widens to form medial & lateral condyles
forming a flat superior articular surface, tibial plateau.
The articular surfaces are separated by an intercondylar eminence
formed by 2 intercondylar tubercles (medial and lateral) flanked by
relatively rough anterior and posterior intercondylar areas.
Medial expansion extends inferior to the rest of the shaft as
medial malleolus.
Interosseous membrane unites the two leg bones.
Inferiorly, the sharp border is replaced by fibular notch.
PATELLA (Knee cap)
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.
Slender, lies posterolateral to the tibia
No function in weight-bearing.
Serves mainly for muscle attachment
Distal end enlarges, projects laterally & inferiorly lateral malleolus
The lateral malleolus is more prominent and posterior than the medial malleolus and
extends approximately 1 cm more distally.
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)
Tarsus (n=7)
Metatarsus (n=5)
Phalanges (n=14)
"flat surface, especially for drying," from PIE base *ters- "to dry" (cf. Gk. teresesthai "to be or
become dry," tersainein "to make dry;" L. terra "land, ground, soil," torrere "dry up, parch
7 bones
Talus
Calcaneus
Cuboid
Navicular
Three cuneiforms
Only one bone, the talus,
articulates with the leg bones.
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TALUS
(L., ankle bone)
Head
Neck
Body
Superior surface trochlea of the talus is gripped by the two malleoli
and receives the weight of the body from the tibia.
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.
(L., heel bone)
Largest and strongest bone in the foot
Lateral surface of the calcaneus has fibular trochlea
Sustentaculum tali shelf-like support of the head of the talus
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(L., little ship)
Flattened, boat-shaped bone
Between head of the talus posteriorly & 3 cuneiforms anteriorly
Medial surface projects inferiorly to form, navicular tuberosity
Most lateral bone in the distal row of the tarsus
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.
METATARSUS
(Anterior foot/distal foot)
5 metatarsals numbered from the medial side of the foot
Metatarsals and phalanges located in anterior half (forefoot)
Tarsals in the posterior half (hindfoot)
14 phalanges
 1st digit (great toe)
2 phalanges
(proximal and distal)
 Other four digits
3 phalanges
(proximal, middle, and distal)
Articulations of the pelvic girdle
Lumbosacral joints, sacroiliac joints & pubic symphysis
The remaining joints of the lower limb
Hip joint
Knee joint
Tibiofibular joints
Ankle joint
Foot joints
Feature 1: Connection between lower limb & pelvic girdle
Feature 2:
2nd most movable after the shoulder joint
Synovial Joint Type: Ball and socket (Head of the femur & acetabulum)
Weight transfer: To the heads and necks of the femurs
Ligaments
Transverse acetabular ligament continuation of acetabular labrum
3 intrinsic ligaments
1)Iliofemoral ligament anteriorly and superiorly , strongest ligament of the body
2)Pubofemoral ligament anteriorly and inferiorly
3)Ischiofemoral ligament posteriorly
Ligament of the head of the femur
MOVEMENTS OF HIP JOINT




Flexion-extension
Abduction-adduction
Medial-lateral rotation
Circumduction
Feature 1: Largest & most superficial joint
Feature 2: Hing movements (Ext/Flex) combined with gliding & rotation
Synovial Joint Type: Hinge
The knee joint consists of three articulations:
2 femorotibial articulations (lateral and medial)
between lateral & medial femoral and tibial condyles
One intermediate femoropatellar articulation
between patella & femur
No fibula involvment in the knee joint.
Extracapsular ligaments
1) Patellar ligament
2) Fibular (Lateral) collateral ligament
3) Tibial (Medial) collateral ligament
4) Oblique popliteal ligament
5) Arcuate popliteal ligament
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INTRA-ARTICULAR LIGAMENTS
Cruciate ligaments & menisci
Anterior cruciate ligament (ACL)
Posterior cruciate ligament (PCL)
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Menisci of the knee joint are crescentic plates of fibrocartilage on the
articular surface of the tibia that deepen the surface and play a role in
shock absorption.
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MOVEMENTS OF KNEE JOINT
Flexion and extension are the main knee movements; some rotation
occurs when the knee is flexed.
When the knee is fully extended with the foot on the ground, the knee passively
“locks” because of medial rotation of the femoral condyles on the tibial plateau (the
“screw-home mechanism”). This position makes the lower limb a solid column and
more adapted for weight-bearing.
http://www.pt.ntu.edu.tw/hmchai/kinesiology/KINlower/Knee.files/KneeKinematics.htm
BURSAE AROUND KNEE JOINT
There are at least 12 bursae around the knee joint because most
tendons run parallel to the bones and pull lengthwise across the joint
during knee movements.
The subcutaneous prepatellar and infrapatellar bursae are located at
the convex surface of the joint, allowing the skin to be able to move
freely during movements of the knee.
The large suprapatellar bursa is especially important because an
infection in it may spread to the knee joint cavity.
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(Superior) Tibiofibular joint
Syndesmosis (inferior tibiofibular) joint
In addition, an interosseous membrane joins the shafts of the two bones.
ANKLE JOINT
Talocrural joint
Distal ends of the tibia & fibula & superior parts of the talus
Synovial Joint Type: Hinge
LIGAMENTS OF ANKLE JOINT
1)
2)
3)
4)
5)
Lateral ligament of the ankle
Anterior talofibular ligament
Posterior talofibular ligament
Calcaneofibular ligament
Medial ligament of the ankle (deltoid ligament)
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Subtalar (talocalcaneal) joint
Transverse tarsal joint (calcaneocuboid and talonavicular joints)
Inversion and eversion of the foot are the main movements
MAJOR LIGAMENTS OF FOOT
Plantar calcaneonavicular ligament (spring ligament)
Long plantar ligament
Plantar calcaneocuboid ligament (short plantar ligament)
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ARCHES OF FOOT
Spreading the weight
Longitudinal arch of the foot
Medial longitudinal arch
Calcaneus, talus, navicular, 3 cuneiforms & 3 metatarsals.
The medial longitudinal arch is higher and more important than the lateral longitudinal
arch.The talar head is the keystone of the medial longitudinal arch.
Lateral longitudinal arch much flatter, rests on ground during standing.
Calcaneus, cuboid, and lateral two metatarsals.
ARCHES OF FOOT
Spreading the weight
Transverse arch of the foot
Runs from side to side
Formed by cuboid, cuneiforms & bases of metatarsals