Study Finds Corticosteroid Injections May Not Hasten Progression of Knee OA
Research suggests that corticosteroid injections for osteoarthritis (OA) of the knee accelerate progression of the disease, leading to a need for total knee arthroplasty (TKA) sooner than if the patient had not had the injection.
However, many patients in studies of corticosteroid therapy have had advanced knee OA, which is a risk factor for disease progression in and of itself. Given that, do these studies really tell the whole story of corticosteroid injections and OA progression?
The answer may be no, according to the findings of new study presented at the ACR Convergence 2020, the annual meeting of the American College of Rheumatology: Patients with knee OA who had corticosteroid injections did not show faster progression of OA or of needing TKA than patients who had hyaluronic acid injections, which have not been associated with cartilage loss.
“The treatment options we have for knee OA are limited. Weight loss can reduce pain from knee OA and delay progression of disease, but this is very difficult for most patients to achieve,” said the study’s co-author, Justin J. Bucci, MD, Assistant Professor of Medicine at Boston University School of Medicine.
“Pain medications cannot be used safely by many patients with OA because of co-existing heart or kidney disease. Steroid injections are considered a safe and effective intervention for relieving pain from knee OA. Recent studies have raised the possibility that steroid injections are associated with progression of OA. Clinicians and patients need to know if steroid injections are making knee OA worse so they can make informed decisions about their treatment.”
Dr. Bucci and colleagues reviewed the rates of radiographic progression of knee OA and TKA in 2 large cohort studies of patients with knee OA who received either corticosteroid or hyaluronic acid injections. Patients in the first cohort visited their physician every 12 months, while those in the second cohort visited their physician every 30 months. Their exams included knee radiographs and questions about steroid or hyaluronic acid injections over the previous 6 months.
Progression of knee OA was measured using 2 standard scores: Kellen and Lawrence grades (KL) and medial joint space narrowing, both of which are radiographic measures. Patients with a baseline KL 4 score were excluded, as were patients who had received either corticosteroid or hyaluronic acid injections in the past.
Radiographs taken before the first injection were compared with those taken after the last injection. KL and joint space narrowing scores were assigned to each radiograph at medical visits where TKA was prescribed.
The researchers included 792 knees in the study, 647 treated with corticosteroid injections and 145 treated with hyaluronic acid injections. They found that the rate of TKA was greater among patients with a single exam and hyaluronic acid injection than in patients with a single exam and corticosteroid injection. They did not find a difference in patients reporting injections at multiple exams. Further analysis showed similar rates of radiographic progression of OA for both injection treatments at either single or multiple medical exams.
The study’s findings show that corticosteroid injections were not associated with higher risk of 2 key signs of worsening knee OA, either radiographic progression or progression to TKA, compared with hyaluronic acid injections.
“We did not find any association between steroid injections and worsening knee OA in our study,” Dr. Bucci said. “Patients and clinicians should see this study and feel reassured that these injections are not causing progression of OA or earlier total knee replacement.”
For future research, Dr. Bucci and colleagues will focus on magnetic resonance imaging (MRI) of knees undergoing steroid injection treatment for OA.
“MRI provides a more detailed look at structures within the knee compared to [radiographs] and these images were obtained as part of the cohorts we studied. This information will add to the findings from our current study and give patients and clinicians a better understanding of what happens to knees treated with steroid injections,” he said.
Bucci J, Chen X, Torner J, Nevitt M, Lewis C, Felson D. Progression of Knee OA with Use of Intra-articular Corticosteroids (CS) vs Hyaluronic Acid (HA). Abstract 1652. Presented at the ACR Convergence 2020, November 5-9, a virtual meeting.