Activity Intensity Matters More than Quantity for Making Joint Replacements Last, Helping Patients Protect Their Artificial Joints

ROSEMONT, Ill., Jan. 25, 2013 /PRNewswire-USNewswire/ -- Joint replacements have a limited lifespan. Implant wear is usually to blame for the necessary revision surgery.  Despite new breakthroughs in the development of advanced polyethylene, longer life-spans and active patient lifestyles have compromised the life-span of the artificial joint.  However, according to a study presented at the Orthopaedic Research Society's 2013 Annual Meeting in San Antonio this month, it appears that the intensity of activity has more impact on implant wear than previously believed.

(Logo: http://photos.prnewswire.com/prnh/20130122/MM45506LOGO)

"It seems like implant wear in patients behaves similar to wear in a car engine where fast driving and many short trips cause higher wear than slow, long distance driving.," said Rachel Senden, author of the study.  In her research, two patient groups with high and low wear but identical characteristics were compared using a new body-fixed sensor to monitor activity in real life for several days.  What the study showed was that the patients with more wear on their implants were those whose walking speed was higher and who walked more short distances.

What does this mean for the thousands of patients who receive artificial joints each year?  "Based on this information," Senden reported, "patients can be better instructed on what protects their joint from wear and what activities can be performed without affecting longevity.  Given our results, patients can protect the longevity of their implants without being less active. "  

Senden was named as a New Investigator Recognition Award Finalist by the Orthopaedic Research Society (ORS) for her work on this topic.

Founded in 1954, the Orthopaedic Research Society strives to be the world's leading forum for the dissemination of new musculoskeletal research findings.  The ORS is made up of over 2,800 clinicians (including orthopaedic surgeons and veterinarians), engineers and biologists.

SOURCE Orthopaedic Research Society