Skeletal System Terminology PDF

 The skeleton forms the framework of the body, protects vital organs, and works with the muscular system to produce movement at the joints. The human adult skeleton is composed of 206 bones, which are organized into two divisions. The skeleton is divided into two portions. The axial skele...

 The skeleton forms the framework of the body, protects vital organs, and works with the muscular system to produce movement at the joints. The human adult skeleton is composed of 206 bones, which are organized into two divisions. The skeleton is divided into two portions. The axial skeleton is shown here in yellow; the appendicular in blue. 1- The axial skeleton forms the central core or “axis” which consists of: A- The skull, made up of 8 cranial bones and 14 bones of the face B- The spinal column consisting of 26 vertebrae. Between the vertebrae are disks of cartilage that add strength and flexibility to the spine. 2- The appendicular skeleton is attached to the axial skeleton A- The upper division includes: The bones of the shoulder girdle, the clavicle (collar bone), and scapula. The bones of the upper extremities (arms), the humerus, radius, ulna, carpals (wrist bones), metacarpals (bones of the palm), and phalanges (finger bones) B- The lower division includes: § The pelvic bones, two large bones that join the sacrum and coccyx to form the bony pelvis. § The bones of the lower extremities (legs), the femur, patella (kneecap), tibia, fibula, tarsals (ankle bones), metatarsals (bones of the instep), and phalanges (toe bones).  Bone formation: Most bone tissue is formed by the gradual addition of calcium and phosphorus salts to cartilage, a type of dense connective tissue. The boneforming process of ossification begins before birth and continues to adulthood. The fibrous protein, collagen, gives bone tissue its strength. Although bone appears to be inert, it is actually living tissue that is constantly being replaced and remodeled throughout life. Three types of cells are involved in these changes: 1- Osteoblasts, the cells that produce bone 2- Osteocytes, mature bone cells that help to maintain bone tissue 3- Osteoclasts, involved in the breakdown of bone tissue to release needed minerals or to allow for reshaping and repair. The process of destroying bone so that its components can be taken into the circulation is called resorption. This activity occurs continuously and is normally in balance with bone formation.  The joints, or articulations, are classified according to the degree of movement they allow: 1- A suture is an immovable joint held together by fibrous connective tissue, as is found between the bones of the skull. 2- A symphysis is a slightly movable joint connected by fibrous cartilage. Examples are the joints between the bodies of the vertebrae. 3- A synovial joint, or diarthrosis, is a freely movable joint. Such joints allow for a wide range of movements. Tendons attach muscles to bones to produce movement at the joints. Freely movable joints are subject to wear and tear, and they therefore have some protective features. The cavity contains synovial fluid, which cushions and lubricates the joint.  Normal Structure Function Bone A calcified form of dense connective tissue; osseous tissue; also an individual unit of the skeleton made of such tissue Bone marrow The soft material that fills bone cavities; yellow marrow fills the central cavity of the long bones Cartilage A type of dense connective tissue that is found in the skeleton, larynx, trachea, and bronchi Diarthrosis A freely movable joint; also called a synovial joint Joint The junction between two bones Ligament A strong band of connective tissue that joins one bone to another Normal Structure Function Ossification The formation of bone tissue Osteoblast A cell that produces bone tissue Osteoclast A cell that destroys bone tissue Osteocyte A mature bone cell that nourishes and maintains bone tissue Pelvis The large ring of bone at the inferior trunk formed of the two hip bones Resorption Removal of bone by breakdown and absorption into the circulation Normal Structure Function The body’s bony framework, consisting of 206 bones; the axial portion (80 bones) is composed of the Skeleton skull, spinal column, ribs, and sternum; the appendicular skeleton (126 bones) contains the bones of the arms and legs, shoulder girdle, and pelvis. Suture An immovable joint, such as the joints between the skull bones Symphysis A slightly movable joint Synovial fluid The fluid contained in a freely movable (diarthrotic) joint Synovial joint A freely movable joint; has a joint cavity containing synovial fluid Tendon A fibrous band of connective tissue that attaches a muscle to a bone  Curvatures of the Spine -Any exaggeration or deviation of spinal curve is described as curvature of the spine. Three common types of spinal curvatures described as follows: 1- Kyphosis is an exaggerated curve in the thoracic region. 2- Lordosis is an exaggerated curve in the lumber region 3- Scoliosis is a sideways curvature of the spine in any region. Spinal curvatures may be congenital or may result from muscle weakness or paralysis, poor posture, joint problems, disk degeneration, extreme obesity, or disease, such as spinal tuberculosis, rickets, or osteoporosis.  Disorder Definition Arthritis Inflammation of a joint Fracture A break in a bone; Gout A form of acute arthritis, usually beginning in the knee or foot, caused by deposit of uric acid salts in the joints Osteoarthritis Progressive deterioration of joint cartilage with growth of new bone and soft tissue in and around the joint Osteomalacia A softening and weakening of the bones due to vitamin D deficiency Osteomyelitis Inflammation of bone and bone marrow caused by infection, usually bacterial  Disorder Definition Osteoporosis A condition characterized by reduction in bone density, most common in women past menopause; predisposing factors include poor diet, inactivity, and low estrogen levels Paget disease Skeletal disease of the elderly characterized by bone thickening and distortion with bowing of long bones Rheumatoid A chronic autoimmune disease of unknown origin resulting in inflammation of peripheral joints arthritis (RA and related structures; more common in women than in men Rheumatoid A group of antibodies found in the blood in cases of rheumatoid arthritis and other systemic factor diseases Rickets Faulty bone formation in children, usually caused by a deficiency of vitamin D Treatment and Procedure Definition Alkaline phosphatase An enzyme needed in the formation of bone; serum activity of this enzyme is useful in diagnosis Arthrocentesis Aspiration of fluid from a joint by needle puncture Arthroplasty Partial or total replacement of a joint with a prosthesis Arthroscopy Use of an endoscope to examine the interior of a joint or to perform surgery on the joint Orthopedics The study and treatment of disorders of the skeleton, muscles, and associated structures  Drug Definition Anti-inflammatory Drug that reduces inflammation; includes steroids, such as hydrocortisone, and nonsteroidal agent antiinflammatory drugs (NSAIDs) Bisphosphonate Agent used to prevent and treat osteoporosis; increases bone mass by decreasing bone turnover Nonsteroidal anti- Drug that reduces inflammation but is not a steroid by inhibiting inflammatory mediator that inflammatory drug produced substances that promote inflammation. Examples of NSAID: aspirin and ibuprofen (NSAID) Selective estrogen Drug that acts on estrogen receptors; raloxifene is used to prevent bone loss after menopause receptor modulator (SERM)