Lower Limb Bones PDF

Bones of the lower limbs pelvic girdle Marriyam Nasim  Pelvic girdle The bones of the pelvic girdle are: 2 innominate bones 1 sacrum  Pelvic girdle innominate bones Each hip bone consists of three fused bones, the ilium, ischium and pubis. On...

Bones of the lower limbs pelvic girdle Marriyam Nasim  Pelvic girdle The bones of the pelvic girdle are: 2 innominate bones 1 sacrum  Pelvic girdle innominate bones Each hip bone consists of three fused bones, the ilium, ischium and pubis. On its outer surface there is a deep depression, the acetabulum, which forms the hip joint with the almost-spherical head of femur.  Pelvic girdle innominate bones The ilium is the upper flattened part of the bone, and it presents the iliac crest, the anterior point of which is called the anterior superior iliac spine. The pubis is the anterior part of the bone, and it articulates with the pubis of the other hip bone at a cartilaginous joint, the symphysis pubis. The ischium is the inferior and posterior part. The union of the three parts takes place in the acetabulum.  Pelvis The pelvis is formed by the two innominate bones which articulate anteriorly at the symphysis pubis and posteriorly with the sacrum at the sacroiliac joints which are synovial joints. It is divided into two parts by the brim of the pelvis, consisting of the promontory of the sacrum and the iliopectineal lines of the innominate bones. The greater or false pelvis is above the brim and the lesser or true pelvis is below.  Pelvis The shape of the female pelvis allows for the passage of the baby during childbirth. In comparison with the male pelvis, the female pelvis has lighter bones, is shallower and more rounded and is generally more roomy.  Lower limb The bones of the lower limb are: 1 femur 7 tarsal bones 1 tibia 5 metatarsal bones 1 fibula 14 phalanges. 1 patella  Femur The femur is the longest and strongest bone of the body. The head is almost spherical and fits into the acetabulum of the hip bone to form the hip joint. In the Centre of the head there is a small depression for the attachment of the ligament of the head of the femur. This extends from the acetabulum to the femur and contains a blood vessel that supplies blood to an area of the head of the bone. The neck extends outwards and slightly downwards from the head to the shaft and most of it is within the capsule of the hip joint.  Femur The posterior surface of the lower third forms a flat triangular area called the popliteal surface. The distal extremity has two articular condyles which, with the tibia and patella, form the knee joint.  Tibia or shin bone The tibia is the medial of the two bones of the lower leg. The proximal extremity is broad and flat and presents two condoles for articulation with the femur at the knee joint. The head of the fibula articulates with the inferior aspect of the lateral condyle, forming the proximal tibiofibular joint.  Tibia or shin bone The distal extremity of the tibia forms the ankle joint with the talus and the fibula. The medial malleolus is a downward projection of bone medial to the ankle joint.  Fibula The fibula is the long slender lateral bone in the leg. The head or upper extremity articulates with the lateral condyle of the tibia forming the proximal tibiofibular joint The lower extremity articulates with the tibia then projects beyond it to form the lateral malleolus  Patella or knee cap This is a roughly triangular-shaped sesamoid bone associated with the knee joint. Its posterior surface articulates with the patellar surface of the femur in the knee joint its anterior surface is in the patellar tendon, i.e. the tendon of the quadriceps femoris muscle.  Tarsal or ankle bones There are seven tarsal bones which form the posterior part of the foot. They are: 1 talus 3 cuneiform 1 calcaneus 1 cuboid. 1 navicula  Tarsal or ankle bones The talus articulates with the tibia and fibula at the ankle joint. The calcaneus forms the heel of the foot. The other bones articulate with each other and with the metatarsal bones  Metatarsal bones of the foot These are five bones, numbered from within outwards, which form the greater part of the dorsum of the foot. At their proximal ends they articulate with the tarsal bones and at their distal ends, with the phalanges. The enlarged distal head of the 1st metatarsal bone forms the 'ball’ of the foot.  Phalanges of the toes There are 14 phalanges arranged in a similar manner to those in the fingers, two in the great toe (the halux) three in each of the other toes  Arch The bones have a bridge-like arrangement and are supported by muscles and ligaments so that four arches are formed Medial longitudinal arch lateral longitudinal arch two transverse arches.  Arch Medial longitudinal arch is formed by the calcaneus, talus, navicular, three cuneiform and first three metatarsal bones. Lateral longitudinal arch is formed by calcaneus, cuboid and the two lateral metatarsal bones. Transverse arches is formed by three cuneiform and cuboid bones.