Patients’ subjective complaints of crepitus (ie, hearing grating, popping, or cracking sounds in and/or around a joint) can predict the development of symptomatic knee osteoarthritis (OA) in the absence of symptoms such as pain, according to the results of a recent study (Lo GH, et al. Arthritis Care Res (Hoboken). 2018;70:53-60).
“Subjective knee crepitus can be used clinically to identify individuals at risk for symptomatic OA, potentially assisting with earlier diagnosis and ultimately with intervention,” wrote lead investigator Grace H. Lo, MD, MSc, Assistant Professor, Section of Immunology, Allergy and Rheumatology, Baylor College of Medicine, Houston, TX, and colleagues.
The investigators evaluated the right knee only using data from the Osteoarthritis Initiative, a longitudinal, observational study of knee OA conducted at 4 clinical sites: Memorial Hospital of Rhode Island (Pawtucket), Ohio State University (Columbus), University of Pittsburgh, and University of Maryland/Johns Hopkins University (Baltimore). Patients were aged 45 to 79 years at the time of enrollment in the initiative (February 2004-May 2006). They underwent body mass index assessment at baseline, as well as evaluation for the presence of crepitus and symptoms at baseline and annual follow-up visits.
The study focused on 3495 patients without baseline symptomatic OA. The investigators assessed frequent knee pain and radiographs at baseline and at annual visits up to 48 months. They also assessed crepitus frequency at baseline and at 12, 24, and 36 months using the following question from the Knee Injury and Osteoarthritis Outcome Score: Do you feel grinding, or hear clicking or any other type of noise when your right knee moves?
At the beginning of the study, 65.1% of patients said they had no crepitus, 10.8% said they experienced it “rarely,” 15.1% said they had it “sometimes,” 5.6% said they had it “often,” and 3.4% said they experienced it “always.” Overall, 636 (18.1%) patients developed symptomatic OA of the knee during the study period.
The odds of developing incident symptomatic knee OA was higher among patients with greater frequency of crepitus (P <.0001). They also found that patients who had radiographic OA but who lacked symptoms at baseline comprised 26% of this group, but >75% of the incident symptomatic OA cases.
Although crepitus frequency resulted in larger odds ratios for incident symptomatic OA in men versus women and in older versus younger patients, crepitus was predictive of incident symptomatic OA in all subgroups.
“Subjective crepitus is a simple and effective assessment that is predictive of the longitudinal development of symptomatic OA. It may offer utility for the identification of at-risk individuals, predictive modeling, and future clinical and epidemiologic research,” the investigators concluded.