Clinical Practice Guideline Revisions Have Influenced the Use of Injections for Knee OA
Recent updates in evidence-based recommendations have led to changes in the use of steroid and hyaluronic acid injections for patients with osteoarthritis (OA) of the knee, reports a study published in The Journal of Bone & Joint Surgery.
Although guideline revisions based on new evidence have stopped or reversed trends toward increased use of injections for knee OA, these treatments are still commonly done, according to the new research from the University of Iowa Hospitals and Clinics, Iowa City, and colleagues.
The researchers evaluated the impact of updated guidelines from the American Academy of Orthopaedic Surgeons (AAOS) for non-surgical treatment of knee OA. The guidelines were issues in 2008 and 2013. The study focused on 2 common treatments to reduce knee pain:
- Corticosteroid injection, intended to reduce inflammation
- Hyaluronic acid injection, intended to supplement synovial fluid within the knee joint
Using an insurance database, the researchers identified more than 1 million patients with knee OA treated between 2007 and 2015. Overall, about 38% patients received at least 1 steroid injection, and 13% had at least 1 hyaluronic acid injection.
Before the first clinical practice guideline, the rate of steroid injections was rising steadily. In the 2008 guideline, the AAOS suggested that steroid injection could be given for short-term pain relief of knee. After this “Grade B” recommendation – reflecting some limitations of the evidence – the rate of increase in steroid injection slowed significantly.
By 2013, there was new conflicting evidence on the effectiveness of steroid injection. In response, the AAOS stated that it could not make any recommendation for or against the use of steroid injection. After this revision, the trend in steroid injection leveled off. Use of steroid injection continued to increase in patients under age 50, perhaps reflecting attempts to avoid total knee arthroplasty (TKA) in this younger age group.
Recommendations for injection of hyaluronic acid were also revised during the study period. In 2008, the AAOS stated that there was no evidence on which to base a recommendation either for or against the use of hyaluronic acid injection. This recommendation slowed a previous trend toward increased use of hyaluronic acid.
By 2013, there was new evidence showing no benefit of hyaluronic acid compared with inactive placebo, prompting a strong recommendation against the use of this treatment. After this revision, the rate of hyaluronic acid injection declined significantly.
There was a significant decrease in hyaluronic acid injections performed by orthopaedic surgeons and pain specialists, but not by primary care physicians or non-surgeon musculoskeletal specialists. Overall, orthopaedic surgeons performed two-thirds of hyaluronic acid injections. Trends in steroid injection did not differ by specialty.
Evidence-based guidelines play an important role in ongoing evaluation of medical treatments. The new findings suggest that guideline updates for knee OA have had a “subtle but significant” impact on clinical practice. Rates of steroid injection leveled off after the AAOS concluded that no recommendation could be made, while the rate of hyaluronic acid injection decreased in response to a recommendation against this procedure.
Some of the same studies that questioned the effectiveness of these treatments also reported that they account for a large proportion of treatment costs for patients with knee OA. Injections given shortly before TKA may even increase the risk of infection.
Bedard NA, DeMik DE, Glass NA, Burnett RA, Bozic KJ, Callaghan JJ. Impact of clinical practice guidelines on use of intra-articular hyaluronic acid and corticosteroid injections for knee osteoarthritis. J Bone Joint Surg Am. 2018 May 16;100(10):827-834. doi: 10.2106/JBJS.17.01045.