Arthroscopic Debridement of the Knee

When you have knee osteoarthritis, it's accepted practice that non-surgical, conservative treatments are tried first when attempting to manage it. When non-surgical treatments fail, it may be time to look into joint surgery. Arthroscopic debridement is one surgical option, but experts have suggested it only be performed on certain patients and for the right reasons.

Understanding Arthroscopic Debridement

You have likely heard arthroscopic debridement referred to in more general terms, such as arthroscopy, arthroscopic surgery, or scoping the knee. Arthroscopic debridement, specifically, involves using surgical instruments to remove damaged cartilage or bone. The surgeon typically does a washout, called a joint lavage, to remove any debris ​around the affected joint. If loose bodies or fragments remain after the lavage, they are removed.

Not too many years ago, arthroscopic debridement was quite common for osteoarthritis patients who found no relief from conservative treatment. It was almost expected that a doctor would suggest scoping a knee to see what was causing relentless osteoarthritis symptoms. But in 2002, an article published in the New England Journal of Medicine changed how arthroscopic debridement was viewed.

Researchers Question Effectiveness of Arthroscopic Debridement

Some thought arthroscopic debridement worked by flushing fluid through the joint during the procedure to rid the knee of debris and possibly inflammatory enzymes. Others believed the improvement was due to the removal of flaps of cartilage, torn meniscal fragments, synovial tissue, and loose debris. But it really wasn't clear what was happening.

The study results that were published in 2002 surprised many, not the least of whom were patients who swore arthroscopic debridement helped them. Researchers had started to suspect that arthroscopic debridement was no more effective than placebo because they lacked any sound explanation for how or why it worked.

In the study, 180 patients with osteoarthritis of the knee were randomly assigned to receive arthroscopic debridement, arthroscopic lavage, or placebo surgery. At no point during the study did patients in the groups receiving arthroscopic debridement or lavage report less pain or improved joint function compared to the placebo group.

The results of the study had a huge impact and there was confusion over who should be having the surgery. Had patients and insurance companies been paying out big bucks for a procedure that had no more effect than placebo?

Cochrane Review of Arthroscopic Debridement

A Cochrane review of research pertaining to arthroscopic debridement was published in 2008 and offered a bit more insight. Three randomized, controlled trials involving a total of 271 patients were included in the review. In one study, compared to lavage, there was no significant difference found for arthroscopic debridement. Compared to placebo (sham surgery), there were worse outcomes for arthroscopic surgery at 2 weeks in terms of pain and function, and no significant difference at two years.

The second study compared arthroscopic debridement with washout and concluded that arthroscopic debridement significantly reduced knee pain at five years. The third study compared arthroscopic debridement to closed-needle lavage and concluded there was no significant difference.

Other research since then has come to the same conclusion: there isn't enough clinical evidence that arthroscopic debridement is effective for osteoarthritis of the knee and it's not a recommended treatment.

The Bottom Line

The American Academy of Orthopaedic Surgeons (AAOS) incorporated the conclusions into their treatment recommendations for knee osteoarthritis. The AAOS states that it cannot recommend arthroscopic debridement and/or lavage to treat osteoarthritis. This recommendation is based primarily on the above-mentioned 2002 study, along with two other similar studies conducted later. However, the recommendation doesn't apply to people with a primary diagnosis of a meniscal tear, loose body, or other derangements in the knee along with osteoarthritis.