Women are greatly affected by this condition -- four out of five cases of osteoporosis occur in women, and half of all women over the age of 50 will have a fracture related to osteoporosis [source: National Osteoporosis Foundation ].
But it also affects men and the young -- in fact, one quarter of all men over 50 will suffer an osteoporosis-related fracture. Though any bone can be affected by osteoporosis, the hip, spine and wrist are the most common. Fractures of the hip and spine are especially problematic, resulting in immobility, severe and lasting pain and even death.
Osteoporosis can lead to a condition called dowager's hump. This occurs when the spine, due to diminished mass and strength, begins to compress, resulting in an outward curve of the upper vertebrae in the spine. Another disease that can affect the bones is bone cancer.
Bone cancer most often spreads to the bone from other parts of the body, but it can also start in the bone. When it begins in the bone, it's known as primary bone cancer. Fortunately, primary bone cancer is pretty uncommon -- there are about 2, new cases discovered each year [source: National Cancer Institute ].
When found, bone cancer can be treated by surgically removing the tumor from the bone or using chemotherapy, radiation therapy or cryosurgery killing cancerous cells by freezing them with liquid nitrogen.
Osteonecrosis is a condition in which bones no longer receive the blood they need to survive, leading to bone death and degeneration. The cause of the disease isn't currently known. Most cases require surgical intervention, and doctors can graft healthy bone onto the diseased portions, attempt to restore blood flow or replace joints with mechanical joints. Osteogenesis imperfecta is an inherited disease that causes bones to be especially brittle. A faulty gene leaves the body unable to produce collagen normally.
For more, read How Osteogenesis Imperfecta Works. Paget's disease of bone affects about 1 million people in the United States and tends to show up more often in people with Northern European ancestry [source: National Institute of Arthritis and Musculoskeletal and Skin Diseases ]. Paget's disease of bone affects seemingly random bones in the body, making them grow too large and structurally unstable. While the disease can affect any bone, it most often affects the pelvis, skull, spine and leg bones.
Sign up for our Newsletter! Mobile Newsletter banner close. Mobile Newsletter chat close. Mobile Newsletter chat dots. Mobile Newsletter chat avatar. Mobile Newsletter chat subscribe. Human Body. Body Systems. Musculoskeletal System. How Bones Work. Bone Basics The Bone Market. There is nothing to prevent you from legally purchasing human bones and skulls from a vendor in the United States.
Bone Marrow Inside the cavities of cancellous bone is soft, fatty tissue comprised of an irregular network of blood vessels and cell types. There are two types of stem cells found in red marrow: Hematopoietic stem cells HSCs.
This type of stem cell is responsible for creating billions of new blood cells daily, at a rate of about 8 million every second [source: Houston Museum of Natural Science ]. HSCs create every type of blood cell: red blood cells which carry oxygen throughout the body , white blood cells which fight infections and kill bacteria and platelets which help your blood clot.
Marrow stem cells can even produce more marrow stem cells. HSCs can leave the marrow and enter the bloodstream, where the ratio of blood cells to stem cells is about ,to-1 [source: National Institutes of Health ].
Stromal stem cells. This type of stem cell generates bone cells, cartilage, fat cells and connective tissue. Stromal stem cells are being studied for their possible use in repairing spinal cord damage and healing disorders of the lymphatic system.
Axial Bones Bones can be broadly divided into two categories: axial and appendicular. Appendicular Bones While the axial bones form the vertical axis of the body, the appendicular bones are the bones that connect to this axis. Let's take a look: Bones of the shoulder. The bones that make up your shoulder girdle serve to connect your arms to your sternum and rib cage for stability and support.
You have two clavicles collarbones that attach on one end to the breast plate and, on the other end, support the shoulder blades, or scapulas. The shoulder blades provide points of contact and attachment for many muscles and the bone of each upper arm. Bones of the arm and hand. The entire arm appendage has three basic components: the upper arm, the lower arm and the hand. The upper arm is one long bone , the humerus. The top fits neatly into the scapula, and the lower end is connected by the elbow joint to the two bones of the lower arm: the ulna the bone on the same side as your little finger and the radius the bone on the side of your thumb.
The radius plays a larger role in your overall mobility and function, while your ulna provides more stability. Both the ulna and the radius connect to the wrist bones in the hand. Each hand has an impressive 27 bones: eight carpal bones that make up the wrist, five metacarpal bones that extend the length of your palm, and 14 phalanges that form four fingers with three bones each along with a single two-boned thumb. The pelvic girdle.
When you sit down, all the weight of your upper body rests ultimately on your pelvic girdle. This tough pair of hip bones protects lower organs such as the bladder and, for women, protects the development of a fetus and facilitates birth. The dimensions of the pelvic girdle differ fairly significantly for men and women, as the opening in the center of the girdle must be large enough for a child to pass through.
Bones of the thigh, leg and foot. Connecting the pelvic girdle to the lower leg is a bone in the thigh area called the femur, the longest and strongest in the body. About 25 percent of your total height is gained from the femur bone [source: Houston Museum of Natural Science ]. The femur connects through the knee joint which is covered and protected by the patella, or kneecap to the shin bone tibia. Slightly smaller than the tibia is the other bone in the leg, the fibula.
The fibula is responsible for muscular connections, while the tibia makes sure your foot and your knee don't get any farther apart from each other. Each foot has 26 bones: seven tarsal bones that make up the ankle, five metatarsal bones that make up the body of your foot and play a significant role in supporting your body's weight , and 14 phalanges that form -- as is the case with your fingers -- four toes with three bones each with a big toe that has two bones.
Next, we'll look at some characteristics of different bone shapes. The Long and Short and Flat and Irregular of It: Bone Shapes The bones in the human body can roughly be divided into four categories: long, short, flat and irregular.
Bess Mensendieck in teaching Body Mechanics. Baby lambs do about 90 percent of their growing at night, and the same may hold true for growing humans. Mending the Break: Healing Broken Bones When bones are fractured, the body immediately initiates the first phase of healing, the reactive phase. Next, we'll learn about what happens when two bones meet in the night or day. Hooking Up: Joints Each time you lean forward, pick up a cup of coffee, raise it to your lips and put it back down, your bones, joints , muscles and other tissues are all working in perfect synchronicity to make this effort possible.
Among them are: Bones. Well yeah, but more precisely, the articular cartilage at the end of the bones. Bones contain more calcium than any other organ. The intercellular matrix of bone contains large amounts of calcium salts, the most important being calcium phosphate. When blood calcium levels decrease below normal, calcium is released from the bones so that there will be an adequate supply for metabolic needs.
When blood calcium levels are increased, the excess calcium is stored in the bone matrix. The dynamic process of releasing and storing calcium goes on almost continuously. Hematopoiesis , the formation of blood cells, mostly takes place in the red marrow of the bones. In infants, red marrow is found in the bone cavities. The information and materials contained on this website are not intended to constitute a comprehensive guide concerning all aspects of the therapy, product or treatment described on the website.
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The State of Victoria and the Department of Health shall not bear any liability for reliance by any user on the materials contained on this website. Skip to main content. Bones muscles and joints. Home Bones muscles and joints. Actions for this page Listen Print. Summary Read the full fact sheet.
On this page. The skeleton The human skeleton is made up of bones, including bones of the: Skull — including the jaw bone Spine — cervical, thoracic and lumbar vertebrae, sacrum and tailbone coccyx Chest — ribs and breastbone sternum Arms — shoulder blade scapula , collar bone clavicle , humerus, radius and ulna Hands — wrist bones carpals , metacarpals and phalanges Pelvis — hip bones Legs — thigh bone femur , kneecap patella , shin bone tibia and fibula Feet — tarsals, metatarsals and phalanges.
Bone types There are four different types of bone in the human body: Long bone — has a long, thin shape. Examples include the bones of the arms and legs excluding the wrists, ankles and kneecaps. With the help of muscles, long bones work as levers to permit movement.
Short bone — has a squat, cubed shape. Examples include the bones that make up the wrists and the ankles. Flat bone — has a flattened, broad surface. Examples include ribs, shoulder blades, breast bone and skull bones. Irregular bone — has a shape that does not conform to the above three types. Examples include the bones of the spine vertebrae. Bone tissue The different layers of bone tissue include: Periosteum — the dense, tough outer shell that contains blood vessels and nerves Compact or dense tissue — the hard, smooth layer that protects the tissue within Spongy or cancellous tissue — the porous, honeycombed material found inside most bones, which allows the bone to be strong yet lightweight Bone marrow — the jelly-like substance found inside the cavities of some bones including the pelvis that produces blood cells.
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