Are you suffering from hip pain or injury? If you are planning for hip replacement surgery, it would be best to know more about this procedure and the types of hip implants used beforehand. Finding the suitable material to match the hip surgery you need is the key to improving your quality of life.
Let’s talk about the types of implants, what you should know about them, and where you can go in Johnson County, KS, for outstanding orthopedic care.
Materials Used for Hip Replacement Implants
Hip implants are supposed to stay inside the body for years, bearing most of the weight. Therefore, they should come from the best materials available, such as:
Polymer materials, such as PTFE, UHMWPE, and PEEK, are known for their excellent mechanical properties and high wear resistance. However, polymer materials trigger the immune system to attack their own structure and loosen over time. As such, the joints may need to be reattached or replaced.
Metals are sturdy and can last years of wear, but most are reactive when implanted on the body. This is why less-corrosive metal alloys, such as cobalt-chromium-molybdenum (CoCrMo), are ideal for hip implants. However, dynamic loading on the joint and the corrosiveness of the body fluids can still degrade the metal alloys.
Ceramics, such as alumina and zirconia, can last longer than polymers and metals. Their nonmetallic and inorganic properties make them the least reactive among the materials for hip implants.
Parts of a Hip Replacement Implant
The hip is a complex and flexible joint, and different replacement implant parts allow similar functions. Below are the specific parts, attachments, and materials of a hip implant.
Stem: Cobalt-Chromium or Titanium
The femoral stem inserted into the thigh bone contains a pin-like end called a trunnion, which holds the ball part of the implant. Cemented stems usually use cobalt-chromium metals, while cementless stems use titanium metals.
Cup: Titanium or Tantalum
The cup or acetabulum, usually made of titanium or tantalum, fits into the pelvic or hip bone. It connects to a liner replacing the bone-to-bone attachment called cartilage. Sometimes a plastic liner without a metal cup attaches to the joint using epoxy bone cement.
Ball: Ceramic or Cobalt-Chromium
The ball is the femoral head that attaches to the trunnion. It can be a ceramic or porcelain-type material that pairs well with ceramic or plastic liners. Cobalt-chromium metals are also popular with plastic liners.
Liner: Ceramic, Cobalt-Chromium, or Polyethylene
For the longest time, polyethylene or plastic has been the standard material for hip liners. Since the liner receives much contact and friction, it is prone to wear and tear. Modern-day improvements now allow longer-lasting liners for ten years and more.
Types of Hip Implants
Here are some recommended combinations of materials for different types of implants:
An MoP is a widely-used hip implant that works efficiently with elderly and less-active individuals. Here, the metal ball adheres to the socket lined with polyethylene. While this causes less friction when the two parts come in contact, the metal can scrape off plastic debris. When debris builds up, it can cause inflammation that loosens the implant over time.
CoP implants are similar to MoP, with the head of the femur comprised of ceramics instead of metal. Like MoP, CoP provides less friction but may also produce plastic debris.
Before the 2000s, MoM implants were comprised of many total hip arthroplasties and hip resurfacing. While metals are sturdy, they also cause more friction. Unlike plastic debris, metallic particles may lead to metal poisoning. Currently, MoM implants are making a comeback with metal finishing technologies that prevent the metals from wearing down.
Ceramic implants address the drawbacks of MoM and MoP implants. Their sturdiness and scratch resistance make them less likely to produce poisonous debris. These advantages make ceramic implants suitable for young and active individuals. However, they are more expensive and require the expert skills of a surgeon.
A recent hybrid in hip implants, CoM comprises a ceramic head on a metal insert. Here, the benefits of higher durability of metal implants and the better wear resistance of ceramics are combined.
Hip Replacement Near You in Johnson County, KS
Hip implants replace the worn-out bones and cartilage of the hip. Implanting these joint replacements requires the care of an expert hip surgeon. If you are planning for hip replacement surgery in Johnson County, KS, look no further than Midwest Orthopaedics. Midwest Orthopaedics takes pride in our highest quality of service. We have also provided joint replacement surgeries to our patients in the Greater Kansas City area.