Which lower leg bone is larger




















Stretching of the ligaments that support the longitudinal arches can lead to pain. This can occur in overweight individuals, with people who have jobs that involve standing for long periods of time such as a waitress , or walking or running long distances. If stretching of the ligaments is prolonged, excessive, or repeated, it can result in a gradual lengthening of the supporting ligaments, with subsequent depression or collapse of the longitudinal arches, particularly on the medial side of the foot.

The lower limb is divided into three regions. These are the thigh, located between the hip and knee joints; the leg, located between the knee and ankle joints; and distal to the ankle, the foot. There are 30 bones in each lower limb. These are the femur, patella, tibia, fibula, seven tarsal bones, five metatarsal bones, and 14 phalanges. Its rounded head articulates with the acetabulum of the hip bone to form the hip joint.

The head has the fovea capitis for attachment of the ligament of the head of the femur. The narrow neck joins inferiorly with the greater and lesser trochanters.

Passing between these bony expansions are the intertrochanteric line on the anterior femur and the larger intertrochanteric crest on the posterior femur.

On the posterior shaft of the femur is the gluteal tuberosity proximally and the linea aspera in the mid-shaft region. The expanded distal end consists of three articulating surfaces: the medial and lateral condyles, and the patellar surface.

The outside margins of the condyles are the medial and lateral epicondyles. The adductor tubercle is on the superior aspect of the medial epicondyle. The patella is a sesamoid bone located within a muscle tendon. It articulates with the patellar surface on the anterior side of the distal femur, thereby protecting the muscle tendon from rubbing against the femur.

The leg contains the large tibia on the medial side and the slender fibula on the lateral side. The tibia bears the weight of the body, whereas the fibula does not bear weight.

The interosseous border of each bone is the attachment site for the interosseous membrane of the leg, the connective tissue sheet that unites the tibia and fibula. The proximal tibia consists of the expanded medial and lateral condyles, which articulate with the medial and lateral condyles of the femur to form the knee joint. Between the tibial condyles is the intercondylar eminence.

On the anterior side of the proximal tibia is the tibial tuberosity, which is continuous inferiorly with the anterior border of the tibia. On the posterior side, the proximal tibia has the curved soleal line. The bony expansion on the medial side of the distal tibia is the medial malleolus.

The groove on the lateral side of the distal tibia is the fibular notch. The head of the fibula forms the proximal end and articulates with the underside of the lateral condyle of the tibia. The distal fibula articulates with the fibular notch of the tibia. The expanded distal end of the fibula is the lateral malleolus.

The posterior foot is formed by the seven tarsal bones. The talus articulates superiorly with the distal tibia, the medial malleolus of the tibia, and the lateral malleolus of the fibula to form the ankle joint. The talus articulates inferiorly with the calcaneus bone. The sustentaculum tali of the calcaneus helps to support the talus. Anterior to the talus is the navicular bone, and anterior to this are the medial, intermediate, and lateral cuneiform bones.

The cuboid bone is anterior to the calcaneus. The five metatarsal bones form the anterior foot. The base of these bones articulate with the cuboid or cuneiform bones.

The metatarsal heads, at their distal ends, articulate with the proximal phalanges of the toes. The big toe toe number 1 has proximal and distal phalanx bones. The remaining toes have proximal, middle, and distal phalanges. Answer: A hole is drilled into the greater trochanter, the bone marrow medullary space inside the femur is enlarged, and finally an intramedullary rod is inserted into the femur.

This rod is then anchored to the bone with screws. Answer: Metal cutting jigs are attached to the bones to ensure that the bones are cut properly prior to the attachment of prosthetic components. Answer: The proximal group of tarsal bones includes the calcaneus and talus bones, the navicular bone is intermediate, and the distal group consists of the cuboid bone plus the medial, intermediate, and lateral cuneiform bones. Answer: A bunion results from the deviation of the big toe toward the second toe, which causes the distal end of the first metatarsal bone to stick out.

A bunion may also be caused by prolonged pressure on the foot from pointed shoes with a narrow toe box that compresses the big toe and pushes it toward the second toe. Define the regions of the lower limb, name the bones found in each region, and describe the bony landmarks that articulate together to form the hip, knee, and ankle joints.

The talus bone of the foot receives the weight of the body from the tibia. The talus bone then distributes this weight toward the ground in two directions: one-half of the body weight is passed in a posterior direction and one-half of the weight is passed in an anterior direction.

Describe the arrangement of the tarsal and metatarsal bones that are involved in both the posterior and anterior distribution of body weight. Skip to content Learning Objectives By the end of this section, you will be able to: Describe the bones of the lower limb, including the bones of the thigh, leg, ankle, and foot Appropriately name the regions of the lower limb and list the bones in each region List the bones and bony landmarks that articulate at each joint of the lower limb.

External Website Watch this video to view how a fracture of the mid-femur is surgically repaired. External Website Visit this site to perform a virtual knee replacement surgery. It is most frequent in adolescents and young adults, and is more common in females. It often results from excessive running, particularly downhill, but may also occur in athletes who do a lot of knee bending, such as jumpers, skiers, cyclists, weight lifters, and soccer players.

It is felt as a dull, aching pain around the front of the knee and deep to the patella. The pain may be felt when walking or running, going up or down stairs, kneeling or squatting, or after sitting with the knee bent for an extended period.

Figure 8. The mid-foot has the five metatarsal bones. There are five surfaces that make up the distal tibia. The inferior surface provides a smooth articulation with the talus.

The anterior surface is covered by extensor tendons and provides an area for ankle joint capsule attachment. The lateral surface has a fibular notch which serves as an attachment for the interosseous membrane. Numerous internal ligaments of the knee joint attach to these tubercles and strengthen it significantly.

On the anterior surface of the proximal region and inferiorly to the condyles is the tibial tuberosity to which the patella ligament attaches.

The shaft of the tibia is triangular and the soleus muscle, which gives the calf its characteristic shape, originates on the posterior surface. Distally, the tibia also widens to aid with weight bearing and it displays two key features. The medial malleolus is a bony projection that articulates with the tarsal bones to form the ankle joint.

Laterally, there is the fibular notch that articulates with the fibula. The Fibula The fibula also spans the lower leg, although proximally it does not articulate with the femur or patella. The tibia does not have epicondyles. The top surface of each condyle is smooth and flattened. These areas articulate with the medial and lateral condyles of the femur to form the knee joint. Between the articulating surfaces of the tibial condyles is the intercondylar eminence , an irregular, elevated area that serves as the inferior attachment point for two supporting ligaments of the knee.

The tibial tuberosity is an elevated area on the anterior side of the tibia, near its proximal end. It is the final site of attachment for the muscle tendon associated with the patella.

More inferiorly, the shaft of the tibia becomes triangular in shape. This forms the large bony bump found on the medial side of the ankle region. Both the smooth surface on the inside of the medial malleolus and the smooth area at the distal end of the tibia articulate with the talus bone of the foot as part of the ankle joint. On the lateral side of the distal tibia is a wide groove called the fibular notch. This area articulates with the distal end of the fibula, forming the distal tibiofibular joint.

The fibula is the slender bone located on the lateral side of the leg see Figure 6. The fibula does not bear weight. It serves primarily for muscle attachments and thus is largely surrounded by muscles.

Only the proximal and distal ends of the fibula can be palpated. The head of the fibula is the small, knob-like, proximal end of the fibula. It articulates with the inferior aspect of the lateral tibial condyle, forming the proximal tibiofibular joint. The distal end of the fibula forms the lateral malleolus , which forms the easily palpated bony bump on the lateral side of the ankle. The deep medial side of the lateral malleolus articulates with the talus bone of the foot as part of the ankle joint.

The distal fibula also articulates with the fibular notch of the tibia. The posterior half of the foot is formed by seven tarsal bones Figure 6. The most superior bone is the talus. This has a relatively square-shaped, upper surface that articulates with the tibia and fibula to form the ankle joint.

Inferiorly, the talus articulates with the calcaneus heel bone , the largest bone of the foot, which forms the heel.



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