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Musculoskeletal conditions - arthritis and osteoporosis

An overview of musculoskeletal conditions - arthritis and osteoporosis

Musculoskeletal conditions are those conditions involving the muscles, the skeleton and the joints.

Muscles, skeleton and joints
Arthritis
Osteoporosis

Muscles, skeleton and joints

Muscle is the contractile tissue that causes the movement of the human body and the organs within the body.

The skeleton is the internal structure composed of bone and cartilage that protects and supports the soft organs, tissues, and other parts of the body. The skeleton is made of bone mineral composed of calcium phosphate embedded in a protein called collagen. A typical adult has about 3 kilograms of solid bone, two-thirds of which is mineral and one-third protein. Bones are very much alive, supplied with blood and essential nutrients and throughout life are in a constant state of new formation and breakdown, which is called bone turnover. They are as liable to disease as any other tissue or organ, but in practice the major disorders to which they are prone are osteomalacia (the adult form of rickets) which is related to a chronic vitamin D deficiency, and osteoporosis.

Joints occur where two bones meet. Most of the joints in the body are freely moving joints called synovial joints which enable bending, stretching and movement. Muscles contract (shorten) to bring the ends closer together and relax (lengthen) to let the ends move apart. Muscles are attached to bones by cord-like extensions called tendons.

Ligaments are strong bands of tissue that attach to the bones and around a joint. Ligaments provide stability to the joint by restricting movement and holding the bones in place.

Arthritis

Arthritis is a group of musculoskeletal conditions in which there is wearing and inflammation of the joints, causing chronic pain, swelling, stiffness, disability and sometimes deformity.

Arthritis can be disabling because of restricted mobility from joint pain or deformity. It is estimated that arthritis affects 3.1 million¹ Australians, with the prevalence of arthritic conditions increasing with age.

The two most common forms of arthritis are osteoarthritis and rheumatoid arthritis, but there are more than 100 known types of arthritis. Arthritis can result from injury, infection, accumulated wear, degenerative changes, metabolic disturbances, autoimmunity or other causes.

Children can also develop arthritis in a number of forms, which are grouped together under the name juvenile idiopathic arthritis. Top of page

Osteoporosis

Osteoporosis is a different musculoskeletal condition that affects almost an estimated 700,000² older Australians and is characterised by progressive loss of bone mass, with decreased density and enlargement of bone spaces producing porosity and brittleness. Among the elderly, osteoporosis is a major cause of pain, disability, deformity, mobility impairment and loss of independence which result from the fracture of bones and related complications³. Osteoporosis is not a form of arthritis.

¹ Page 16, 2007-08 National health survey: summary of results report by the ABS, May 2009
² Page 17, 2007-08 National health survey: summary of results report by the ABS, May 2009
³ Page 13, Arthritis and osteoporosis in Australia 2008, AIHW, December 2008

Page last reviewed: 23 August 2010