Arthroscopy of the Knee – New Lessons Learned
By Ken Cohen, MD, FACP, Chief Medical Officer
Arthroscopy of the knee is the most common orthopedic surgical procedure performed. In the past, when patients had moderate knee arthritis and significant pain, surgeons used to do arthroscopy to try and "clean up the knee" and thereby improve pain and function. High quality studies were subsequently done which showed this to be of no value in terms of reduction of pain or increase in function and this practice was discarded. New research has extended the observations to patients who do not have significant knee arthritis, but do have knee pain and tears in the meniscus of the knee.
The Fidelity Trial was an elegant study published in the New England Journal of Medicine last year. It looked at patients with knee pain who did not have arthritis, but had evidence of a torn meniscus on MRI. The study group was divided in two. One group had arthroscopic surgery. The other group was taken to the operating room and had "sham surgery" with anesthesia, IV's, knee incisions, and all the sounds of the arthroscopy equipment so that neither patient group knew whether they had the true or the sham surgery. Patients were then followed for a year and it turns out there was no benefit whatsoever to the surgical procedure. It seems that tears in the meniscus occur naturally over time as part of the aging process and surgical repair of this type of tear does not appear to be of any value. In fact, when people at age 50 with no knee complaints are studied with an MRI, half of them have tears in the meniscus of which they were unaware. There is still a role for knee arthroscopy when there has been a traumatic injury to the meniscus such as with a ski or basketball injury, or when the pain does not respond to time and physical therapy. This study also does not apply to arthroscopy of the knee done for ligament tears such as the ACL.
As we apply rigorous science to common scenarios, we often learn that our current therapies do not offer the benefits we once thought. This area of medical science is called "evidenced based medicine" and it allows us to learn the optimal care we should provide to our patients.