Corticosteroid Injections May Be Safe for Patients with Knee OA
Osteoarthritis (OA) of the knee affects 1 in 8 Americans over the age of 50 and is associated with pain, dysfunction, and reduced quality of life. Intra-articular corticosteroid injections have been commonly used to manage knee pain in these patients and delay the need for surgical intervention.
However, in recent years, recommendations for intra-articular corticosteroid injections have been tepid at best, based on concerns that these injections can actually damage structures in the knee.
Kompel et al  documented 4 radiologic findings associated with intra-articular corticosteroid injections: rapid progression of OA, subchondral insufficiency fracture, osteonecrosis, and rapid joint destruction. Zeng et al  also cited radiographic progression of OA as a reason to be cautious about intra-articular corticosteroid injections, while cartilage volume loss was associated with these injections in a study by McAlindon et al. 
In 2021, the American Academy of Orthopaedic Surgeons published an updated guideline on non-arthroplasty treatment of knee OA.  The previously Strong recommendation for intra-articular corticosteroid injections was downgraded to Moderate, “because of [the] potential risk in accelerating osteoarthritis from [these] injections.” 
A Different View
But now, a new study is challenging these concerns: Researchers from Boston University School of Medicine found that corticosteroid injections in the knee do not cause significant cartilage loss or increase the risk of total knee arthroplasty.
As mentioned above, previous studies have suggested that intra-articular corticosteroid injections could accelerate progression, including cartilage loss. However, “a limitation of previous studies is that subjects receiving [corticosteroid injections] were not compared to those receiving comparable treatment,” said study co-author David T. Felson, MD, MPH, a professor of medicine and epidemiology at Boston University School of Medicine and Boston University School of Public Health
“Patients receiving [corticosteroid injections] have more advanced knee OA, itself a risk factor for disease progression.”
The findings from the Boston University School of Medicine study have been published online ahead of print by Arthritis & Rheumatology.
For this study, Dr. Felson and his colleagues used data from 2 large observational, prospective cohort studies, the Osteoarthritis Initiative (OAI) and the Multicenter Osteoarthritis Study (MOST), to evaluate treatments and outcomes among participants with knee OA.
They wanted to know which patients had received an intra-articular corticosteroid or hyaluronic acid injection in the knee and which patients had subsequently undergone total knee arthroplasty, as well as the interval between injection and surgery. They chose to compare corticosteroid injections with hyaluronic acid injections because the latter has been reported to delay knee replacement and it is thought to have no effect on cartilage loss.
On an annual basis during the OAI study and every 30 months during the MOST study, participants completed a questionnaire that asked whether they had received an intra-articular injection in the previous 6 months. Radiographs were obtained at baseline and at each of the study visits to assign Kellgren and Lawrence grades to the knees and to measure joint space narrowing as a way of assessing OA progression.
Of the 791 participants (980 knees) included in the study, 629 participants (773 knees) reported receiving corticosteroid injections and 162 (207 knees) reported receiving hyaluronic acid injections. The researchers found that after 7 years of follow-up, radiographic progression of OA occurred at similar rates for the 2 groups: Study participants who received corticosteroid injections had no greater cartilage loss than those who received hyaluronic acid injections.
Interestingly, the rate of total knee arthroplasty was actually higher for study participants who received a hyaluronic acid injection than for those who received a corticosteroid injection.
Patients may receive intra-articular corticosteroid injections in an attempt to relieve pain and delay the need for total knee arthroplasty. But in recent years, they and their physicians may have been reluctant to start these injections due to study results highlighting the risk of OA progression related to the injections.
“Our data should provide reassurance to clinicians and patients,” Dr. Felson said. “The risk of OA progression attributed to [corticosteroid injections] in earlier studies may reflect more advanced disease in those receiving the injections.”
Bucci J, Chen X, LaValley M, et al. Progression of knee osteoarthritis with use of intraarticular glucocorticoids versus hyaluronic acid. Arthritis Rheumatol. 2021 Nov 22. doi: 10.1002/art.42031. Online ahead of print.
- Kompel AJ, Roemer FW, Murakami AM, Diaz LE, Crema MD, Guermazi A. Intra-articular corticosteroid injections in the hip and knee: perhaps not as safe as we thought? Radiology. 2019 Dec;293(3):656-663. doi: 10.1148/radiol.2019190341. Epub 2019 Oct 15.
- Zeng C, Lane NE, Hunter DJ, et al. Intra-articular corticosteroids and the risk of knee osteoarthritis progression: results from the Osteoarthritis Initiative. Osteoarthritis Cartilage. 2019;27:855-62.
- McAlindon TE, LaValley MP, Harvey WF, et al. Effect of intra-articular triamcinolone vs saline on knee cartilage volume and pain in patients with knee osteoarthritis: a randomized clinical trial. JAMA. 2017;317:1967-75.
- American Academy of Orthopaedic Surgeons. Management of Osteoarthritis of the Knee (Non-Arthroplasty): Evidence-Based Clinical Practice Guideline. Published 08/31/2021. Available at https://www.aaos.org/oak3cpg; accessed January 6, 2022.