ESTABLISHING A KNEE PRESERVATION REGISTRY TO FOLLOW PATIENTS WITH DEGENERATIVE JOINT DISEASE

Purpose: The Joint Preservation Registry (JPR) is a prospective, pragmatic, observational study, designed to identify clinical and biochemical markers of osteoarthritis (OA) phenotype, status and progression. Because the time course of degenerative joint disease is highly variable, the optimal treatment for an individual patient is clinically determined by multiple factors, and highly variable between both clinicians and patients. Few large data sets are available studying the ways that clinicians and patients handle this uncertainty, particularly with respect to the timing of surgical intervention. To address this gap in knowledge, the JPR was established to follow consenting patients who present with knee symptoms to physicians at the center for musculoskeletal care of a large tertiary care medical center. The JPR also is intended to evaluate whether synovial fluid biomarkers previously found to be predictive of radiologic progression and knee replacement over a 3-year period, are also predictive of pain score progression over shorter time periods, and useful for optimizing treatment pathways. Methods: Patients presenting with knee-related complaints were recruited into a Knee Preservation Registry, asked to consent to regular follow-up by email or phone every 6-12 months, and to allow any bio-specimens collected during the course of their standard care to be retained in a bio-repository for future analyses. Participating investigators included both physicians and surgeons from the divisions of Sports Medicine, Rheumatology, and Adult Reconstruction. Inclusion criteria were deliberately broad to enable a diverse patient population, ranging from recent acute injury to advanced degenerative disease, and including patients with comorbidities. The registry is observational and captures demographics, medical history, anthropometrics, diagnosis codes, treatments, imaging, and patient-reported outcome (PRO), with much of the data directly retrieved from the medical record. Synovial fluid (SF) biomarker analysis and PRO score collection at regular follow-up are the only study-related procedures. Patients will be followed for 5 years from the time of enrollment. Results: From September 2012 to July 2014, 813 patients (M = 340, F = 473) were recruited for the registry. The average age at enrollment was 52.3 years. SF was aspirated from 167 subjects (225 knees, 57 bilateral, 111 unilateral), for a total of 302 unique SF samples in the current bio-repository which represents 21% of the total population that was sampled. The same percentage of patients with effusion was noted to be the same (21%) among men and women. Distribution of diagnoses, defined by ICD-9, was 72% for osteoarthritis (OA), 10% for acute injuries, and 18% for other non-OA complaints. Approximately half of the enrolled patients have reached the 6-12 month follow-up. Conclusions: To our knowledge, this is the first pragmatic registry for knee OA patients that are not scheduled for knee replacement. The information captured by our registry can be used to study disease phenotypes as they relate to treatment alternatives, including ethnic, racial, socioeconomic and gender disparities. Ultimately we hope to establish evidence-based treatment pathways using a combination of biomarkers, PRO scores and advanced imaging to customize the treatment of OA to individual patient needs and preferences, and to assist surgeons in determining the appropriate timing for joint replacement.