Cemented VS. Cementless Fixation
The debate over whether to fix an implant with cement, via the natural growth of the bone, or through a hybrid of the two methods, is somewhat controversial among orthopaedists.
The cemented method has been the standard since hip implants were first widely introduced in the mid-20th century. The method allows for a quick, relatively painless recovery, and enables the implant to bear weight almost immediately.
However, cemented fixations are occasionally prone to two complications. Cracks in the cement around the femoral stem can cause the implant to loosen over time, and microscopic particles of cement or polyethylene can wear away and be released into the surrounding tissue, provoking an immune-system response that can result in osteolysis, or bone loss, as the body tries to rid itself of the foreign material. Active or heavy patients are more prone to these side effects.
Cementless fixation was introduced in the 1980s in an attempt to avoid the risks of cemented fixation. Cementless implants have a rough, porous surface that allows bone to adhere to the implant and hold it in place. Because of the need for bone regrowth to hold the implant, recovery time is significantly longer for cementless fixation, and patients will often be required to use crutches or other aids until the implant is secure. Cementless implants are often initially fixed in place with screws or something similar until bone regrowth can occur.
Sources on manufacturers related to Hip Replacement:
Taking Samples of blood or heart muscle
Measuring oxygen levels throughout the heart
Checking the hearts pumping function (verticulogram)
Diagnosing congenital heart defects
Cementless fixation also requires that the bone’s shape precisely match the shape of the implant. Patients may experience mild thigh pain if the implant fails to adhere correctly, and osteolysis due to polyethylene debris remains a problem. However, the implants are often prescribed to younger, more active patients, and those in which optimal bone regrowth can be reasonably predicted. Because this method is newer than cemented fixation, less is known about the long-term results.
A hybrid fixation features one component attached with cement and another with a cementless implantation. This is based on high success rates of cementless acetabular sockets and cemented femoral stems. Long-term results are still being studied.
A meta-analysis of existing studies published in 2013 found a slightly elevated, but not statistically significant, rate of revision surgeries in patients with cemented implants. The study ultimately recommended the use of cemented implants, but acknowledged that further research is necessary on individual patient populations. As with any medical procedure, your doctor can help you determine what surgical method and type of fixation is right for you.
General Surgical Risks And Complications
Any surgical procedure comes with a level of risk, and whichever method of hip replacement you choose, you should be sure to discuss the potential complications with your doctor ahead of time.
|Surgical Risks and Complications
|Reaction to anesthesia
||Anesthetic can, in extremely rare circumstances, lead to serious complications, including heart attack, stroke, pneumonia and blood clots. Age and other medical factors such as diabetes or a history of smoking may contribute to these risks.
||Blood clots in the legs can occur after the surgery and may not appear for several days after the procedure, accompanied by swelling and pain in the legs. The clots can be dislodged and move to the lungs, causing shortness of breath, chest pain, and, in the worst cases, death. Getting out of bed after surgery and moving around will help to decrease the risks of clots, as will physical therapy. You may be asked to wear special stocking or take blood thinners for a short period after the surgery to decrease the likelihood of forming these clots.
||Infection can occur deep where surgery took place or at the skin level at the site of the incision. If the infection involves the replaced hip, revision surgery may be necessary to remove the implant.
||Excessive bleeding either during or after the operation may require transfusion.
||Areas close to the surgical area may become damaged in the implantation process, including the arteries and veins in the leg.
||Painful or unsightly scarring can occur after an incision heals. Proper care of the wound after surgery may prevent some scarring and aid the healing process.
Risks Specific To Hip Replacement
In addition to the risks inherent in any surgical procedure, replacing a hip has some unique complications, many of which are interrelated. For example, osteolysis can be one symptom of metallosis, while a squeaky implant could be caused by a number of factors, and may or may not indicate serious problems with an artificial hip.
Potential complications of hip arthroplasty include:
- Nerves going to the leg may become damaged, decreasing sensitivity and causing weakness in the limb
- The replaced joint may become loose or detached from the adjoining bone
- The “ball” of the prosthesis may become dislocated from the socket
- A difference in leg length may occur due to the newly added hip
- Stiffness in the joint area that may feel abnormal
- Bone fracture
- Bone loss (osteolysis) due to an immune reaction to debris wearing away from the implant and entering the blood and tissue around the device
- Metallosis, a form of metal poisoning that can be caused by metal-on-metal implants
- Squeaking, clicking or other noise during movement
- Avascular necrosis, bone damage due to lack of blood flow (usually associated with hip resurfacing, rather than total replacement)
- Heterotopic ossification, calcification of soft tissue around the joint
In some cases, these complications can lead to corrective surgery.
Recovery After Hip Replacement Surgery
Make sure to pay attention to the limitations specific to your surgery. You may not be able to bend your hip, cross your legs or sit up in bed.
Do not cross your legs
Do not bend your body more than 90 degrees at the waist
Do not sit on low sofas or seats that may make it difficult to get up
Avoid sleeping on your side
Recovery After Hip Replacement Surgery
Make sure to pay attention to the limitations specific to your surgery. You may not be able to bend your hip, cross your legs or sit up in bed. Physical therapy is important after the surgery. With proper physical therapy you should be able to increase your range of motion, but in order to keep your implant from dislocating or otherwise being damaged, you will need to restrict certain movements during your recovery.
Post-Surgery Dislocation Prevention
- Do not cross your legs
- Do not bend your body more than 90 degrees at the waist
- Do not sit on low sofas or seats that may make it difficult to get up
- Avoid sleeping on your side
In the early stages of recovery, it is important to gradually increase your range of motion in the joint. As you heal and you gain strength in your hip muscles, you may slowly resume most of your normal day to day activities. This may, at times, require the use of a walker to decrease the stress on the joint and allow proper healing. Due to the amount and extent of physical therapy required and the initial difficulties with getting around/movement, it may become necessary for a short stay at an extended care facility to improve the outcome of the surgery. Speak with your doctor and the appropriate staff in order to make the necessary plans for your stay.