December 08, 2017
3 min read

It is time to revisit viscosupplementation guidelines

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Since “Treatment of Osteoarthritis of the Knee (Non-Arthroplasty)” was released by the American Academy of Orthopaedic Surgeons in 2013, there has been concern about these clinical practice guidelines as they relate to the use of viscosupplementation for the treatment of knee osteoarthritis. The controversy has been based upon the evidence reviewed to determine efficacy and whether this evidence was interpreted correctly.

Anthony A. Romeo, MD
Anthony A. Romeo

There are three issues regarding the review process used by the AAOS. Was the metric minimal clinically important improvement (MCII) and minimal clinically important difference utilized appropriately by the AAOS clinical practice guidelines (CPGs) group when evaluating the articles reviewed? Should it have evaluated the viscosupplementation class as a whole, or should it have separated high-molecular-weight (HMW) and crosslinked viscosupplementation from low-molecular-weight (LMW) viscosupplementation? Is there recent compelling clinical evidence that should be considered prior to continuing to substantiate the AAOS recommendation?

From the literature

When the CPGs were first published, the Arthroscopy Association of North America solicited epidemiologist Raveendhara R. Bannuru, MD, FAGE, from Tufts University, to review the methodology associated with the guidelines. Bannuru and his co-authors concluded the “AAOS methodology contained numerous flaws in obtaining, displaying and interpreting MCII-based results.” In Bannaru’s 2015 updated systematic review and network meta-analysis, which included eight randomized controlled trials for a total of 2,199 patients, viscosupplementation significantly reduced pain and improved function at 3 months, providing a real benefit for patients with knee OA.

The literature is replete with evidence confirming the significant difference between HMW/crosslinked and LMW viscosupplementation. In 2016, Johal and colleagues stated “closer evidence around viscosupplementation favors clinically important reductions in pain among higher molecular weight and crosslinked formulations and is a safe option in patients with knee osteoarthritis.” The review suggests the guidelines may provide “inaccurate and misinformed recommendations” and a “careful examination of the most recently published articles suggests that viscosupplementation is a safe option with a clinical reduction in pain for younger patients with osteoarthritis in those formulations with higher molecular weights or hyaluronic acid crosslinking.”

By not differentiating the classes of viscosupplementation when understanding that LMW viscosupplementation does not provide significant efficacy and then applying that conclusion to the entire class of viscosupplementation, is inappropriate. Perhaps a reasonable analogy to this evaluation would be to state that “total hip arthroplasty is not useful in the treatment of OA of the hip” based upon a review of metal-on-metal THA failure rates and thus concluding the entire treatment class should be banned. Additionally, there are four articles published since 2014, plus a recent Cochrane review representing more than 65,120 patients, which conclude viscosupplementation is efficacious in the treatment of mild to moderate OA of the knee.

Jack M. Bert
Jack M. Bert

Time to revisit

There has never been a major payer non-coverage decision on the use of a treatment modality for patient care based upon a CPG until the AAOS recommendation against the use of viscosupplementation. Since publication, several commercial insurers have issued non-coverage determinations. Now with Anthem’s recent decision, more than an additional 40 million patients with commercial insurance will lose coverage for viscosupplementation.

It is time for the AAOS Research, Quality, and Scientific Affairs Committee to revisit the evidence or even encourage subspecialty societies to create their own evidence-based CPGs. We are reminded of Mark Twain’s quote, “ It ain’t what you don’t know that gets you into trouble. It’s what you know for sure that just ain’t so.”

Disclosure: Romeo reports he receives royalties, is on the speaker’s bureau and a consultant for Arthrex; does contracted research for Arthrex and DJO Surgical; receives institutional grants from AANA and MLB; and receives institutional research support from Arthrex, Ossur, Smith & Nephew, ConMed Linvatec, Athletico and Miomed. Bert reports he is a consultant for Zimmer Biomet and Acceler; is on the speaker’s bureau for Sanofi and Flexion Therapeutics; and is a consultant for Cardinal, Exscribe ,Element and Episode Management Inc.