Hip and knee joints require replacement due to a number of factors but the most common by far are the different types of arthritis. Arthritis inflames and deteriorates the cartilage in the early stages and eventually will wear away the cartilage until the bones of the joint are rubbing against each other causing friction and pain.
Another reason many people will have to undergo hip or knee replacement is due to an accident that damages the joint. The success of hip and knee replacement will vary depending on the amount of damage that has occurred to the joint.
Osteonecrosis is a third condition that may require hip and knee replacement. Where with arthritis there is a deterioration of the cartilage, with osteonecrosis the bone in the joint actually dies and collapses under the stress of use. The most common causes of osteonecrosis are heavy use of alcohol or cortisone medication, although in many cases the cause is never determined.
The most common contributing factor of osteoarthritis and the leading cause of hip or knee replacement is obesity. According to a Canadian Institute for Health Information 2003/04 report, 90% of knee replacements and 70% of hip replacements were performed on overweight or obese people.
Additionally, it is an accepted fact that people who are considered obese will require more time in the hospital to recover from joint replacement and will require more repeat procedures during their lifetimes.
Sex and Age
Women are more likely to have hip and knee surgery than men. About 60% of all hip and knee replacements are done on women.
Seniors are the most common recipients of hip and knee replacements with between 65% and 70% receiving theses procedures. The least common group, at around 5% for hip replacements and only 1% for knee replacements, is those under 45 years of age.
Although the number of replacements for those under 45 years of age is relatively low, the number of procedures done on this group has risen significantly in the past ten years.
THIS MATERIAL DOES NOT CONSTITUTE MEDICAL ADVICE. IT IS INTENDED FOR INFORMATIONAL PURPOSES ONLY. PLEASE CONSULT A PHYSICIAN FOR SPECIFIC TREATMENT RECOMMENDATIONS.