We are going to cover the lower limb series for the pelvic and the hip. The lower limbs from the proximal to distal start from the pelvis to the thigh to the lower leg, the ankle and the foot. The functions of the lower limb are specialized for the local motion to support our body weight and maintain our balance. When we are standing on our feet, the transfer of the body weight starts from the vertebral column to the sacroiliac joints of the pelvic girdle, to the hip joints, to the femurs, to the knee joints, to the tibia of the ankle joints and to the talus of the ankle joints, the tarsal bones, to the metatarsal bones and to the phalanges. This is what it looks like for the lower limb. The pelvis is the area of the transitions between the trunk and the lower limbs. We have the pelvic cavity. It is a continuation of the abdominal cavity into the pelvis through the pelvic inlets. This is the pelvic girdle and we've got some boundaries. For the superior parts, we have the pelvic inlet and for the inferior part, we have the pelvic outlets. The anterior part is the pubic symphysis, and the posterior part is the coccyx. The pelvic girdle is a basin-shaped ring of bones surrounding the pelvic cavity. Which connects the vertebral column with the two femurs. The function of the pelvic girdle is to transfer the body weights of the upper body. The pelvic girdle can withstand compressions and other forces resulting from the body weight supports. It also houses and protects the pelvic viscera. These are the bones of the pelvic girdle, and we have left and right hip bones. The hip bones are fused with three separate bones. They are the ilium, the ischium, and the pubis. We have acetabulum on the hip bones, it is cup-shaped and articulates with the femur heads. We have the sacrum by fusion of the five sacral vertebrae. And we have the coccyx. This is the terminal end of the vertebral column. We may refer it as the tailbone. The shape of the pelvis is a little bit different between the two genders, the male and the female. For the male one, it is generally heavier and thicker. The subpubic angle is much narrower, it's usually less than 70 degrees. And it’s with a round obturator foramen and larger acetabulum. For the female pelvis, it's lighter and thinner with a larger subpubic angle, usually, it's larger than 80 degrees. And that obturator foramen, it's oval in shape, and the acetabulum is smaller in general. These two photos show all the ligaments of the pelvic girdle. Because its function is to support the body weight, it has to be very rigid. The sacral-iliac joint is one of the synovial joints on the pelvis. It locates between the ilium and the sacrum. It allows for load transfer between the spine and the lower extremities. This joint is not very mobile because it has to take up the weight of our body. This is the pubic symphysis. The pubic symphysis is a cartilaginous joint formed by the pubic bones in the median plane. For the surface anatomy, we can wrap our hands around the pelvis. Usually, we get to the iliac crests, which are usually the top of the pelvic bone. If we follow through anteriorly, we can reach the anterior superior iliac spine which we may refer to it as the ASIS. At the back, we reach the posterior superior iliac spine, or we call it the PSIS. And usually, there are two dimples at PSIS. Now we move on to the hip. There are two bones for the hip joints. It's formed by the pelvis and the femurs. The hip joint is a classic ball and socket synovial joint. It provides stability and fairly mobility. It allows the following actions: flexion, extension, abduction, adduction, medial rotation, lateral rotation, and limited circumduction. Now we look at the femur. The femur is one of the largest bones in the body. We have the head of the femur, the neck of the femur, the greater trochanters, and the lesser trochanters. For the hip joints, which we refer to the gluteal region, the muscles here we can divide into two groups. One would be the superficial muscles and the other would be the deep muscles. For the deep muscles, they are the piriformis, the gemellus superior, obturator internus, gemellus inferior and quadratus femoris. These muscles attached the pelvis to the femur head. For the superficial muscles, they are the gluteus maximus, the gluteus medius, the gluteus minimus and the tensor fascia latae. We look at the muscles of the thigh. We can divide the thigh into three muscular compartments by the intermuscular septae. First, the anterior compartment or we call the extensors group. Second, we have the medial compartment, we call the adductor group. Lastly, we have the posterior compartment, or we can call it the flexor group. Now, we look at the anterior compartment of the thigh muscles. We have very big muscles called the hip flexors. It’s formed by the iliopsoas muscles which compose of the psoas major and the iliacus muscles. It starts from the posterior abdominal wall and travels to the anterior thigh. The second muscle would be the sartorius. The third muscle would be the quadriceps femoris. For the medial compartment of the thigh, we have the pectineus, adductor brevis, adductor longus, adductor magnus and gracilis. Now, we move on to the posterior compartment of the thigh. Basically, we have three muscles. As you can see on the screen, they are the circled ones. They are referred to the hamstring muscles, they are the semimembranosus, semitendinosus and biceps femoris. We look at the surface anatomy, you may want to know the ischial tuberosity is located in the sitting bone. It can be easily palpated in the inferior part of the buttocks when the hip joint is flexed. We can easily locate it when we are sitting. Its function is to bear the body weight. For the greater trochanter, we may palpate it on the lateral side of the hip. It's around 10 cm inferior to the iliac crests. These are the major arteries of the lower limb. It starts with the femoral artery and it runs downwards pass the knee joint, the anterior tibial artery and the fibular artery. Down to the foot and ankle, we have the dorsalis pedis artery and the plantar arterial arch. Now we move on to the major nerves of the lower limb. On the anterior side of the thigh, we have the femoral nerves. Until we passed the knee joint, we have the common fibular nerves which branch into deep fibular nerves and the superficial fibular nerves. For the posterior part of the thigh, we have the sciatic nerves run all the way down to the lower legs into the tibial nerves and the sural nerves on the lateral side. There are some fun facts about the angle of inclination for the femur. For adults, usually, the range is around 115 degrees to 140 degrees. On average that will be around 126 degrees. However, this angle of inclination are different for children and the elderly. These are some fun facts for your reference. Now it comes to the end of this session. Thank
