Joints of the lower limb - Study these joints on the prosections
The hip joint
The hip joint is a ball and socket joint and consists of the head of the femur (ball) which fits snugly in a
deepened cavity, the acetabular fossa (socket). The joint allows free movement in all directions. The
fibrous capsule is a very thick sleeve (compare to the capsule of the shoulder joint) further thickened as a
series of extremely strong ligaments which hold the bones in position.
1. Review the bony features that are relevant to the hip joint:
- Acetabulum - formed by the three bones, the ilium, ischium, pubis
- Acetabular notch
- Head of the femur
- Fovea for ligament of the head of the femur
- Neck of the femur
- Intertrochanteric line of the femur
- Intertrochanteric crest of the femur
2. On the anterior view of the hip: (Figure 499, 563)
- Identify the iliopsoas muscle, a powerful flexor of the thigh to its attachment on the lesser
trochanter of the femur. The tendon of the Iliopsoas muscle guards the anterior part of the
capsule of the hip joint
- Reflect the muscle medially and laterally and identify the fibrous capsule. Proximally it is
attached to the acetabular brim, labrum and transverse acetabular ligament and distally along the
whole length of the intertrochanteric line of the femur.
- Identify the iliofemoral ligament, a broad, strong band attached proximally to the anterior
inferior iliac spine and distally to the intertrochanteric line of the femur. (Figure 563). The
iliofemoral ligament becomes lax in flexion and taut in extension. It prevents overextension of
the hip joint
3. On the posterior view of the hip, from superior to inferior, identify the following muscles and then
reflect them medially and laterally: (Figure 506, 564)
- Gluteus medius and gluteus minimus muscles. These attach to the greater trochanter. They
abduct and medially rotate the thigh.
- Piriformis muscle attaches to the greater trochanter. It laterally rotates the extended thigh.
- Superior gemellus muscle, obturator internus muscle and inferior gemellus muscle attach
to the greater trochanter. All 3 muscles are reflected as a group. All are lateral rotators of the
extended thigh.
- Quadratus femoris muscle attaches to the intertrochanteric crest. It laterally rotates the thigh.
- Obturator externus tendon lies just deep to the quadrates femoris muscle. It is also a lateral
rotator of the thigh.
4. Identify the sciatic nerve as it enters the gluteal region below the piriformis muscle. It then passes
inferiorly superficial to the obturator internus muscle, superior and inferior gemellus muscles and the
Quadratus femoris muscle.
5. With the above muscles reflected, identify the capsule of the hip joint. Note that posteriorly the
capsule does not extend all the way to the intertrochanteric crest and part of the neck of the femur is
“bare” or extracapsular. (Figure 564). The capsule is thinnest and weakest posteriorly.
6. Identify the ischiofemoral and pubofemoral ligaments which extend horizontally across the capsule
of the joint from the acetabular margin to the neck of the femur. The ischiofemoral ligament also becomes
taut and limits extension of the hip joint.
7. On the dissected cadaveric specimen of the pelvis:
- On the left hip joint, identify the iliofemoral, ischiofemoral and pubofemoral ligaments.
Flex and extend the thigh at the hip joint and observe that the iliofemoral ligaments become taut
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- On the right hip joint, a circumferential cut has been made on the joint capsule. Observe that
the head of the femur is held firmly within the deepened acetabulum. Remove the head of the
femur from the acetabulum.
- Identify the articular cartilage of the head of the femur (Figure 567)
- Identify the cut end of the ligament of the head of the femur and the fovea for the
ligament of the head of the femur (Figure 567)
- On the acetabulum, identify the lunate surface in the acetabulum. Identify the
acetabular labrum, a fibrocartilagenous rim which deepens the joint cavity so that the
femoral head is not easily dislocated from the joint cavity (Figure 568)
- Inferiorly the bony acetabulum is incomplete and is known as the acetabular notch.
It is partially covered by the transverse acetabular ligament
- Identify the ligament of the head of the femur and observe that it is attached to either
side of the acetabular notch (Figure 568)
Note: Return the femoral head into the joint cavity when you have finished studying the internal
aspect of the hip joint.
The knee joint
The knee joint is of the hinge variety. The chief movements occurring at the knee joint are flexion and
extension. However a slight degree of medial rotation of the femur is necessary to the completion of the
act of extension (“locking” of the joint).
1. Review the bony features that are relevant to the knee joint. The 3 bones are the femur, tibia and
patella. The fibula is only indirectly associated with the knee joint.
- Medial condyle of the femur
- Lateral condyle of the femur
- Intercondylar fossa of the femur
- Medial condyle of the tibia
- Lateral condyle of the tibia
- Superior articular surface of the tibia
- Intercondylar eminence of the tibia
- Articular surface of the patella
- Anterior surface of the patella
2. On the anterior view of the knee (Figure 497) identify
- Quadriceps femoris muscle and tendon
- Patella
- Patellar ligament
Reflect the quadriceps femoris muscle, tendon, patella and patellar ligament inferiorly and identify
(Figure 572)
- Suprapatellar bursa
- Articular surface of the patella
- Alar and interpatellar synovial folds
- Medial femoral condyle
- Lateral femoral condyle
- Patellar surface of the femur
3. On the medial view of the knee (Figure 5.25) identify
- Sartorius and gracilis muscles, which have been cut and reflected together
- Semitendinosus tendon
- Semimembranosus tendon
- Tibial collateral ligament (Figure 5.65)
4. On the lateral view of the knee (Figure 527) identify
- Biceps femoris tendon attaching on the head of the fibula
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- Iliotibial tract (Figure 5.63)
- Fibular collateral ligament (Figure 5.63)
5. On the posterior view of the knee (Figure 517, 545, 575)
- Reflect the popliteal vessels inferiorly
- Reflect the lateral head of the gastrocnemius muscle inferiorly and identify the popliteus
muscle. Observe that the popliteus tendon passes between the fibular collateral ligament and the
joint capsule.
- The arcuate popliteal ligament spans the superficial surface of the popliteus tendon
- Reflect the medial head of the gastrocnemius muscle inferiorly and identify the
semimembranosus tendon which expands upward and laterally as the oblique popliteal
ligament. It reinforces the posterior surface of the joint capsule.
- On the posterior surface of the joint capsule observe the genicular arteries piercing the joint
capsule.
The ankle joint
The ankle joint is the most frequently injured major joint in the body. Motion at the ankle consists purely
of dorsiflexion and plantarflexion. It is a hinge joint. Functional inversion and eversion of the foot occurs
at the transverse tarsal joint between the talus and navicular bones medially, and the calcaneus and cuboid
bones laterally.
1. Review the bony features relevant to the ankle joint
- Lateral malleolus on the distal end of the fibula
- Medial malleolus on the distal end of the tibia
- Articular surface of the body of the talus
2. On the medial view of the ankle (Figure 534)
- Reflect the flexor retinaculum and identify the tendons of Tibialis posterior, Flexor digitorum
longus and Flexor hallucis longus muscles
- The joint capsule is thickened as the deltoid ligament (Figure 606). It is attached above to the
medial malleolus and spreads out inferiorly to attach to the navicular, the talus and the
sustentaculum tali of the calcaneus. Note: The different parts of the deltoid ligament are named for
the bones they connect.
3. On the posterior view of the ankle (Figure 602)
- Reflect the calcaneal tendon inferiorly and observe that the joint capsule is very thin.
- Identify the posterior tibiofibular ligament which somewhat strengthens the posterior aspect of
the joint capsule.
- For your interest: Note that a small accessory bone, the os trigonum, is present. The os
trigonum is the most commonly occurring accessory bone in the foot, occurring in an estimated
eight to ten percent of the population. This interesting bone sits at the most posterior aspect of the
talus, at the border of the talus and the calcaneus.
4. On the lateral view of the ankle (Figure 533)
- Identify the tendons of the fibularis longus and fibularis brevis muscles
- The joint capsule is thickened as the lateral collateral ligament (Figure 604) which is attached
above to the lateral malleolus and below as 3 slips to the talus and navicular.
5. On the anterior view of the ankle (Figure 5.82)
- Reflect inferiorly the extensor retinaculum and identify the tendons of the Tibialis anterior,
Extensor hallucis longus and Extensor digitorum longus muscles.
- Identify the medial and lateral malleoli
- Identify the anterior tibiofibular ligament (Figure 5.117)
- The joint capsule is thin anteriorly and has been incised to expose the joint cavity. Identify the
articular surface of the body of the talus (Figure 5.117)
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