Hip replacement has become commonplace over the past ten years. Aging joints which would normally cause the elderly to spend their twilight years walking with a cane can now be replaced. In addition, younger patients who suffer hip injuries and breakage may also benefit from a hip replacement.
People with the following conditions are prime candidates for hip replacement:
- Rheumatoid Arthritis
- Osteonecrosis or avascular necrosis
- Injury or fractures
- Bone tumors
Acetabular Cup System Defects
Acetabular cup system replacements have problems specific to the mechanism when installed. First of all, many acetabular cup systems create a coverage angle that is too shallow. Why is this important? The coverage angle describes how the ball portion of the implant fits inside the hip socket. If the ball portion fits deep within the socket, it will last and not cause pain and discomfort to the patient. Unfortunately, if the ball portion fits deep in the socket, the patient has a limited range of motion. On the other hand, if there is a shallow socket fitting, the patient has a lot of motion but there is a greater potential for wear and increased instances of failure. There have also been complaints regarding the ball portion of the implant. If it is negligently designed and manufactured it can also caused increased metal wear and increased instances of failure.
Many acetabular systems are incredibly difficult for surgeons to implant. Experts have found an unacceptable differential of the cup and femoral head caused by the technique and manner of the heat treatment of these parts. Doctors are unable to orient the system as there are no screw holes to look for and its design lends itself to surgical error. This can cause high instances of faulty implantation that can cause many patients pain and discomfort.
To make matters worse, the metal on metal design of many hip replacement systems can cause metal toxicity due to chromium and cobalt ions being released into the blood.
How Do I Know if My Acetabular System is Faulty?
Most people experience the same basic symptoms:
- Elevated chromium levels
- Pain which limits your ability to walk and move freely
- Creaking and popping noises when walking
- Difficulty when standing from a sitting position
- Sensation that the hip is out of joint
- Pain in the hip, groin, thigh or lower back
Artificial hips are supposed to last between 20 and 25 years. Discovering that you will have to undergo revision surgery within a few years of implant because of a defect in a hip replacement system would upset anyone. This is compounded by the fact that hip revision surgery, when compared to the original hip prosthesis operation, can be a more difficult procedure because of the loss of the patient’s bone. Hip revision surgery often has a less successful result than the original hip replacement surgery. Additionally, the recovery time is much greater and usually reaches six months before the patient is able to walk without a cane.