Sigma Knee Replacements

Sigma knee replacements by DePuy Orthopaedics are designed to provide more of the normal movement you would expect from the knee. After knee surgery these knee replacement implants can allow slightly more rotation while the knee flexes, thus accommodating your body's normal need for knee rotation.

This kind of rotating knee platform is relatively new, pioneered more than thirty years ago by Revra DePuy in Warsaw, Indiana. Based on a mobile-bearing knee, it allows for nearly full knee rotation and can handle more stress that previous types of prosthetic knees. The amount of knee flexion a patient see's after surgery will depend on a number of factors.

Patients used to not expect more than 100 degrees of knee bending ability. The amount of knee flexion from a total knee replacement surgery can vary. With Sigma rotating platform knee implants, the amount a patient can expect is more than previously found in other types of operations - up to 155 degrees bending ability. This is obtained through early and aggressive physiotherapy. Not all Sigma DuPuy knee replacement patients will get such a high degree of knee replacement flexion. Cycling is an activity that promotes the building of hamstrings and quadriceps. Swimming is also a positive exercise for rebuilding strength and flexibility in the knee.

Problems with earlier knee replacement implants were due to the fact that as the knee rotates, there is more stress on the joint. Early implants couldn't support the stress, or the ligament couldn't be attached in such a way to allow mobility. Stress on the joint accelerates the aging process of a knee after implant surgery. The Sigma Rotating Platform Knee replacement, conversely, is designed to handle the stress, increasing the longevity of the knee. These new DePuy rotating platform knee implants have been proven to reduce wear by up to 90%. Studies indicate that nearly 97% of patients are still functioning on their implants after 20 years. Over a million Sigma Knee Replacement implants have been done worldwide.

New surgery techniques also allow for less scar tissue. Previously, knee replacements were done through incisions of about 14- 20 cm long. This not only created larger scars on the thighs, but damaged more muscle, creating more scar tissue underneath, a detriment to mobility. Now, special instruments mean the operation can be performed through a new, modified surgical technique which prevents carving up the quadriceps in the thigh. This means post operative pain is significantly less, and recuperation is faster. Learn more at: http://www.knee-replacement-video.com.