The
last ten years have seen surgical replacement of hip joints with an artificial
prosthesis increase significantly. The main reason for this surge in hip
replacement surgeries is our aging population. With people living longer, more
active lives, degenerating hip joints can put a halt to that activity. From
1997 through 2004, the number of hip replacement surgeries increased nearly 50%
and if the trend continues it is estimated that the annual number of hip
replacements in the United States will reach 600,000 by 2015.
Factors in Hip Replacement Surgery
Primary
reasons for patients undergoing hip replacement surgery include chronic pain,
impairment of daily functions and severe arthritis in the hip joint. The most
common type of arthritis leading to total hip replacement is osteoarthritis and
is generally seen with aging or trauma to the hip joint. In some instances
necrosis of the hip can be present, usually caused by a fracture, alcoholism,
lupus, or taking steroid drugs such as prednisone. Patients may experience
progressively worsening chronic pain which prohibits them from walking,
climbing stairs or even getting up from a sitting position.
Types of Hip Implants
There
are many different types of hip replacement implant including the metal-on
metal, metal-on-polyethylene and metal-on-ceramic as well as the implants which
are 100% ceramic or polyethylene. Other than the materials the implant is
constructed with, the only other major difference is in how the implant is
affixed—it can be cemented to the bone or attached in such a manner that it
grows into the patient’s remaining bone. The idea behind the cobalt and
chromium metal-on-metal hip implant was to create an implant which would not
have to be re-done for fifteen to twenty years—unlike the ceramic and
polyethylene hip implants which last approximately 8-12 years.
