Patients who have problems with tibial loosening after undergoing a knee replacement surgery might have DePuy CMW-1 bone cement to blame.

Surgeons use bone cement in many knee implant surgeries. The adhesive helps the new artificial parts attach to the femur and the tibia. The femur is the thigh bone, and the tibia is the shinbone.

Patients might mistake cement failure for implant failure because many of the symptoms are similar.

Knee replacement surgeries secured with bone cement that show signs of problems within the first three years of surgery could be the fault of the adhesive. DePuy CMW-1 bone cement is a high-viscosity product. The high viscosity makes the texture preferable to surgeons because it is easier to shape and manipulate.

High-viscosity cement (HVC) is easier to mix and takes less time to set, but investigations have begun because some patients claim HVC does not bond as well to the bone as well as low-viscosity or medium-viscosity adhesives.

The National Center for Biotechnology Information (NCBI) analyzed 13 cases of knee implant failure that occurred when the component either loosened from the shinbone or the implant part failed to stay attached to the cement. Every one of the failed knee implants had been secured with HVC. No similar problems were reported when low- or medium-viscosity cements were used.

Another retrospective analysis by the NCBI found that of 3,048 knee replacement operations in 2013, nine of them failed with HVC to blame.

DePuy CMW-1 Bone Cement Problems

When an implant loosens without concurrent infection, the result is known as aseptic loosening. If the bone cement chips or the cement’s bond breaks with the bone, the aseptic loosening can result in a host of problems.

Indications that DePuy CMW-1 bone cement may have failed to remain attached to the bone include:

• Constant pain
• New, chronic pain
• Unstable knee
• Aseptic loosening of the knee implant
• Swelling
• Decreased range of motion

An X-ray might not be able to show that the knee implant has moved from its intended position, but a bone scan can help the doctor see if tibial loosening due to cement failure is to blame.

Symptoms of DePuy CMW-1 Bone Cement Implantation Syndrome

Because the surgeon applies bone cement to the live bone, some patients experience a reaction to the toxins in the adhesive. Faulty performance of bone cement can lead to bone cement implantation syndrome, which can cause:

• Oxygen deficiency
• Low blood pressure
• Unexpected loss of consciousness
• Blood clots
• Cardiac arrest
• Heart arrhythmias
• Increased pulmonary vascular resistance
• Fat/bone marrow emboli (an embolism caused by the releasing of fat or marrow pieces into the bloodstream)
• Death

If the bone cement is applied with too much pressure, the bone marrow, fat or bone fragments might break off and flow into the bloodstream.

DePuy faces legal action initiated by patients who blame HVC for early failure of their knee implants caused by tibial loosening. Patients allege the bone cement fails to properly adhere to the surface of the bone, resulting in pain, disability and the need for knee revision surgery.