Accelerated knee OA characterized by meniscal tears, cartilage loss
Accelerated knee osteoarthritis involves cartilage loss, large bone marrow lesions and destabilizing meniscal tears in knees that demonstrate meniscal damage in at least two regions, according to data published in Arthritis & Rheumatology.
“Typically, knee osteoarthritis is a slowly progressive disorder,” Jeffrey B. Driban, PhD, of Tufts Medical Center, told Healio Rheumatology. “However, a subset of adults develops an accelerated form of knee osteoarthritis, which is defined by the rapid onset and progression of disease within 4 years, from preradiographic disease to advanced-stage disease. Two out of three adults with accelerated knee osteoarthritis develop accelerated knee osteoarthritis in less than 12 months.”
“These patients also have greater pain and disability than peers without accelerated knee osteoarthritis and are more likely to receive a knee replacement over the course of a decade,” Driban added. “Unfortunately, we don’t understand why these patients develop accelerated knee osteoarthritis and if they are different from other adults at risk for knee osteoarthritis.”
To analyze whether accelerated knee OA is preceded and characterized by destabilizing meniscal tears or other pathologic changes, Driban and colleagues studied three groups of patients, matched by sex, from the first 48 months of the Osteoarthritis Initiative.
Driban and colleagues focused on patients with accelerated knee OA, defined as a KellgrenLawrence grade of 3 or greater, typical knee OA or no knee OA.
All three groups included 125 patients, matched by sex. The index visit was defined as the visit when the radiographic criteria for accelerated and typical knee OA were met. The observation period lasted for up to 2 years before and after an index visit. Radiologists reported on any destabilizing meniscal tears — including root, radial or complex tears — as well as meniscal damage, acute ligamentous or tendinous injuries, attrition, subchondral insufficiency fractures and other incidental findings. The researchers measured bone marrow lesions and cartilage damage on magnetic resonance images.
According to the researchers, at 1 year prior the index visit, more than 75% of patients included in the study with accelerated knee OA had meniscal damage in at least two regions, compared with those with typical knee OA (OR = 3.19; 95% CI, 1.7-5.97). At the time of the index visit, meniscal damage in more than two regions was ubiquitous throughout the accelerated knee OA group, with 42% demonstrating a destabilizing meniscal tear, compared to 14% among those with typical knee OA. According to the researchers, these changes corresponded to larger bone marrow lesions and greater cartilage loss.
“These findings may help us develop strategies to identify patients who are at risk for accelerated knee osteoarthritis and help us develop prevention strategies,” Driban said. “It’s important to appreciate that potentially one in five to seven people with incident knee osteoarthritis may develop an accelerated form of knee osteoarthritis so we need to keep an eye out for these patients.”
“Furthermore, if adults with accelerated knee osteoarthritis are distinct from those with typical knee osteoarthritis then this raises critical concerns about suggestions that clinical trials for knee osteoarthritis would benefit from recruiting people with faster progression,” he added. “Instead, the current findings may indicate that separate trials may be needed for accelerated knee osteoarthritis and other forms of knee osteoarthritis, because accelerated knee osteoarthritis has a unique natural history defined by the onset of a destabilizing meniscal tear in a joint compromised by the presence of multiple pathologies.” – by Jason Laday
Disclosure: The researchers report grant support from the NIH. Please see the study for all other additional relevant financial disclosures.