Lower limb

Back of left lower extremity

The lower limb, an essential component of human anatomy, plays a pivotal role in locomotion, balance, and weight-bearing. It stretches from the pelvis down to the toes, encapsulating an array of bones, muscles, vessels, and nerves that collectively facilitate movement and sensation.

The Components of the Lower Limb

The lower limb can be methodically dissected into distinct regions, each possessing its unique anatomical structures and functions.

Pelvic Girdle

The pelvic girdle acts as a sturdy connection between the axial skeleton and the lower limbs. It is composed of:

Two coxal (hip) bones, which further subdivide into:

• Ilium
• Ischium
• Pubis

The union of these bones at the acetabulum forms a socket for the head of the femur, thereby constructing the hip joint.

Buttocks

Located posteriorly to the pelvis, the buttocks house:

Gluteus Maximus, Gluteus Medius, and Gluteus Minimus: Muscles instrumental in hip extension, abduction, and rotation. The region also possesses a substantial fat deposit, providing cushioning during sitting.

Hip

The hip is a ball-and-socket joint formed between:

The acetabulum of the pelvic girdle The head of the femur (thigh bone) It facilitates a broad range of movements including flexion, extension, abduction, adduction, and rotation.

Thigh

Situated between the hip and the knee, the thigh houses:

• Femur: The longest and strongest bone in the human body.

Muscles groups like:

• • Quadriceps (anterior): Important for knee extension.
  • Hamstrings (posterior): Involved in knee flexion and hip extension.

Components Distal to the Knee

Following the thigh, the lower limb further extends to include:

Leg: Encompassing the region between the knee and the ankle. It contains two bones:

• • Tibia: Medially located and weight-bearing.
  • Fibula: Laterally situated and non-weight-bearing.

Foot: Divided into the hindfoot, midfoot, and forefoot. It plays a crucial role in balance, weight distribution, and propulsion.