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)
.
HIP JOINT
 Iliofemoral ligament [body's strongest ligament] Y
anterior inferior iliac spine & acetabularrim proximally & intertrochanteric line distally
prevents hyperextension of the hip joint during standing by screwing the femoral
head into the acetabulum
 Pubofemoral ligament
arises from the obturator crest of the pubic bone
prevents overabduction of the hip joint
 Ischiofemoral ligament [weakest of the three] .
arises from the ischial part of the acetabular rim
spirals around the femoral neck, medial to the base of the greater trochanter
Ligament of the head of the femur
 a synovial fold conducting a blood vessel.
 weak and of little importance in strengthening the hip joint.
 attaches to the margins of the acetabular notch & fovea for the ligament of the
head.
.
MOVEMENTS OF THE HIP JOINT
During extension of the hip joint, the fibrous layer of the joint
capsule, especially the iliofemoral ligament, is tense; therefore, the
hip can usually be extended only slightly beyond the vertical except
by movement of the bony pelvis (flexion of lumbar vertebrae).
From the anatomical position, the range of abduction of the hip joint
is usually greater than for adduction.
.
About 60° of abduction is possible when the thigh is extended, and
more when it is flexed. Lateral rotation is much more powerful than
medial rotation.
Patellar ligament patella to the tibial tuberosity.
Collateral ligaments of the knee
stabilize the hinge-like motion of the knee.
tense when the knee is fully extended, contributing to stability while standing.
As flexion proceeds, increasingly loose, permitting and limiting (serving as check
ligaments for) rotation at the knee.
Fibular collateral ligament
from lateral epicondyle of femur to lateral surface of the fibular head
.
Tibial collateral ligament
from medial epicondyle of femur to medial condyle & superior part of medial surface of tibia
weaker than the FCL, is more often damaged. As a result, the TCL and medial meniscus are
commonly torn during contact sports such as football.
Oblique popliteal ligament
arises posterior to medial tibialcondyle and passes superolaterallytoward lateral femoral condyle.
Arcuate popliteal ligament
arises from posterior aspect of fibular head, and spreads over the posterior surface of the knee joint.
strengthens the joint capsule posterolaterally.
.
Intracapsular (internal) ligaments of the knee joint
1.1. Anterior cruciate ligament (ACL)
weaker of the two cruciate ligaments.
from anterior intercondylar area of tibia to medial side of the lateral condyle of the femur.
1. limits posterior rolling (turning and traveling) of the femoral condyles on the
tibial plateau during flexion.
2. prevents posterior displacement of the femur on the tibia
3. prevents hyperextension of the knee joint.
.
Intracapsular (internal) ligaments of the knee joint
1.2. Posterior cruciate ligament (PCL)
stronger of the two cruciate ligaments.
from posterior intercondylar area of the tibiato lateral surface of medial condyle of femur
1. limits anterior rolling of the femur on the tibial plateau during extension.
2. prevents anterior displacement of the femur on the tibia
3. prevents posterior displacement of the tibia on the femur
4. helps prevent hyperflexion of the knee joint.
In the weight-bearing flexed knee, the PCL is the main stabilizing factor for the femur
(e.g., when walking downhill).
.
Intracapsular (internal) ligaments of the knee joint
2.1. Medial meniscus is C shaped,
anterior end (horn) is attached to the anterior intercondylar area of the tibia, anterior
to the attachment of the ACL.
posterior end is attached to the posterior intercondylar area, anterior to the
attachment of the PCL.
Because of its widespread attachments laterally to the tibialintercondylararea and medially to the TCL,
the medial meniscus is less mobile on the tibialplateau than is the lateral meniscus.
2.2. Lateral meniscus is nearly circular, smaller, and more freely movable than the
medial meniscus.
.
The stability of the knee joint depends on:
(1) the strength and actions of the surrounding muscles and their
tendons
(2) the ligaments that connect the femur and tibia.
The erect, extended position is the most stable position of the knee.
.
JOINT
TYPE
MOVEMENT
Hip
Ball and socket
flexion-extension, abductionadduction, medial-lateral
rotation, and circumduction
Knee
Hinge
flexion-extension
combined with gliding and rolling and with rotation about a vertical axis
Superior tibiofibular
Inferior tibiofibular
Ankle
Plane
slight movement during dorsiflexion
SYNDESMOSIS
Hinge
dorsiflexion and plantarflexion
Iliofemoral ligament
Ischiofemoral ligament
Ligament of the head of the femur
Pubofemoral ligament
Extracapsular (external) ligaments
Patellar ligament
Fibular collateral ligament (lateral collateral ligament)
Tibial collateral ligament (medial collateral ligament)
Oblique popliteal ligament
Arcuate popliteal ligament
Intracapsular (internal) ligaments
Anterior and posterior cruciate ligaments
Lateral and medial menisci
Anterior and posterior ligaments of the fibular head
Anterior talofibular ligament
Posterior talofibular ligament
Calcaneofibular ligament
Hip joint
Knee joint
Superior tibiofibular joint
Ankle joint