Anteroposterior (A) and lateral (B) radiographic views of the knee in a woman with severe patellofemoral arthritis associated with mild degenerative changes in the medial and lateral compartments.Reproduced from O’Connor ML: Sex Differences in Osteoarthritis of the Hip and Knee. J Am Acad Orthop Surg 2007;15(suppl 1):S22-S25


Published 2/1/2009
John C. Richmond, MD

AAOS adopts clinical practice guidelines on OA Knee

Recommendations focus on less invasive treatments

Approximately 10 million adults in the United States are estimated to have symptomatic osteoarthritis (OA) of the knee. Although joint replacement remains one of the most cost-effective treatments available for end-stage OA knee, a myriad of treatment alternatives are available for less severe cases. But which are the most effective? Which have the best evidence supporting their use? Where can orthopaedic surgeons go to review the evidence and apply it to their clinical decision making?

To answer these and other questions, the AAOS has begun developing evidence-based clinical practice guidelines (CPG). The most recent guideline, approved by the AAOS Board of Directors at its December 2008 meeting, covers the treatment of OA knee (not including arthroplasty). The guideline covers a wide range of treatment options, enabling physicians and patients to tailor a treatment program that meets the patient’s specific circumstances.

The purpose of the CPG on OA knee is to assist the practitioner improve treatment of patients with moderate OA of the knee, who do not require joint replacement arthroplasty, by applying the current best evidence in making clinical decisions. It is intended for use by orthopaedic surgeons and other qualified practitioners managing OA of the knee.

22 recommendations
The clinical practice guideline resulted in 22 specific recommendations in the following categories: lifestyle modifications, rehabilitation, mechanical interventions, alternative therapies, pain relievers, intra-articular injections, needle lavage, and surgery.

Each recommendation is graded based on the total body of evidence available to recommend for or against the intervention. The four recommendations that received an “A” grade are supported by good evidence (consistent Level I studies). The nine grade “B” recommendations are supported by fair evidence (consistent Level II and III studies). Nine other recommendations received either a grade “C”, indicating poor quality evidence (Level IV or V), or an “Inconclusive” if evidence was insufficient or conflicting (Table 1).

The low number of grade A recommendations indicates that significant areas in the treatment of OA of the knee require additional high quality research. In particular, the following areas would benefit from well-done Level I or II studies:

  • flexibility exercise programs
  • “unloading” type braces for unicompartmental OA of the medial or lateral tibiofemoral articulation
  • acupuncture
  • viscosupplemantation
  • partial meniscectomy or loose body removal
  • osteotomies

Better studies of these therapies will allow for clearer recommendations as to their role in the treatment of OA of the knee in the future. The workgroup hopes that the dissemination of these guidelines will encourage musculoskeletal researchers to address the holes in our base of evidence. Finally, these guidelines, although up-to-date as of the completion of the literature search in February 2008, will need to be modified in the future to reflect the ever evolving body of knowledge for care of OA of the knee.

A summary of the recommendations can also be found on the AAOS Web site. The workgroup strongly recommends that practitioners not rely solely on the summary, but that they consult the full guideline and evidence report as well. Treatment decisions for an individual patient depend on all of the circumstances presented by that patient and mutual communication between the patient and the treating practitioner.

John C. Richmond, MD, chaired the workgroup that developed the Clinical Guideline on the Treatment of Osteoarthritis of the Knee (nonarthroplasty). He can be reached at

How the guidelines came to be
The Clinical Practice Guideline for the Treatment of Osteoarthritis of the Knee (Non-Arthroplasty), adopted by the AAOS Board of Directors at their December 2008 meeting, was developed by a multidisciplinary volunteer workgroup that included orthopaedic surgeons, physical therapists, a rheumatologist, and a family physician, with assistance from the AAOS guidelines unit.

Funding was provided by the AAOS, with additional funding from the Arthroscopy Association of North America and the American Orthopaedic Society for Sports Medicine.

The guideline is based on a systematic review of the current scientific and clinical information on accepted approaches to treatment and/or diagnosis. The entire process included a review panel of internal and external committees, public commentaries, and final approval by the AAOS Board of Directors.

The methods used to prepare this guideline were rigorous, employed to minimize bias and to develop a set of reliable, transparent, and accurate clinical recommendations for treating OA of the knee. These methods are detailed in the full guideline.

In addition to the processes employed by the workgroup and the AAOS guideline unit in their systematic review of the literature, the evidence report “Treatment of Primary and Secondary Osteoarthritis of the Knee” prepared for the Agency for Healthcare Quality and Research and the previously published Osteoarthritis Research Society International treatment guidelines were also used to address certain questions.