Anatomy of Lower Limbs

Lower Limb

• The lower limb consists of four major parts: hip bone (girdle), thigh (femur), leg (tibia and fibula), and foot (tarsal, metatarsal, and phalanges)

Hip Bone

• The hip bone is composed of three parts: ilium, pubis, and ischium
• The ilium is the widest and largest part of the hip bone, located superiorly
• The ilium has two surfaces: inner surface (iliac fossa) and outer surface (gluteal surface)
• The pubis is the most anterior part of the hip bone, consisting of a body, superior ramus, and inferior ramus
• The pubis articulates with the opposite pubic body at the pubic symphysis
• The ischium forms the posteroinferior part of the hip bone, composed of a body, inferior ramus, and superior ramus
• The ischial tuberosities are the posterior inferior aspects of the ischium, where body weight falls when sitting

Articulations of Hip Bone

• The hip bone has three main articulations: sacroiliac joint, pubic symphysis, and hip joint

Femur

• The femur is the longest bone in the body, acting as a site of origin and attachment of many muscles and ligaments
• The femur is divided into three parts: proximal, shaft, and distal
• The proximal end of the femur articulates with the acetabulum of the pelvis to form the hip joint
• The proximal end consists of a head, neck, and two bony processes: greater and lesser trochanters
• The shaft of the femur descends in a slight medial direction, increasing stability
• The distal end of the femur is characterized by the presence of medial and lateral condyles, which articulate with the tibia to form the knee joint

Patella

• The patella is a triangular bone located at the front of the knee joint, protecting the anterior aspect of the knee joint from physical trauma
• The patella articulates with the femur, with two facets: medial and lateral

Tibia

• The tibia is the main bone of the lower leg, forming the shin
• The proximal tibia is widened by the medial and lateral condyles, forming a flat surface called the tibial plateau
• The tibial plateau articulates with the femoral condyles to form the knee joint
• The shaft of the tibia is prism-shaped, with three borders and three surfaces
• The distal end of the tibia widens to assist with weight-bearing, with a medial malleolus and a fibular notch

Fibula

• The fibula is a bone located in the lateral aspect of the leg, acting as an attachment for muscles
• The fibula has three main articulations: proximal tibiofibular joint, distal tibiofibular joint, and ankle joint
• The lateral malleolus is a prominent bony projection on the distal end of the fibula, articulating with the talus bone of the foot

Foot

• The bones of the foot provide mechanical support for soft tissues, divided into three groups: tarsals, metatarsals, and phalanges
• The tarsals are a set of seven irregularly shaped bones situated proximally in the foot
• The metatarsals connect the phalanges to the tarsals, with five in number
• The phalanges are the bones of the toes