Evaluating Posterior Cruciate Ligament Integrity in Inflammatory Arthritis Patients Prescribed Biologic Agents: A Radiological Case-Control Study

Introduction Patients with inflammatory arthropathies present a significant challenge to the arthroplasty surgeon when they present with symptomatic degenerative changes of their knee joint. Debate is ongoing regarding the selection of implants for this cohort of patients. There is conflicting evidence for the use of posterior-stabilising (PS) over cruciate-retaining (CR) designs in this cohort. Biologics are licensed for use in moderate-to-severe disease that has not responded to conventional treatment. To our knowledge, there are no studies that have assessed the integrity of the posterior cruciate ligament (PCL) on magnetic resonance imaging (MRI) in these patients with more advanced disease prescribed biologic agents. Aim The aim of this study is to assess the integrity of the PCL on MRI in patients with inflammatory arthritis who are prescribed biologic agents. Methods A case-control study was performed, with cases identified through chart review to confirm prescription of biologic agents for inflammatory arthropathies, who also had contemporaneous MRI knee scans performed. Knee MRIs for age- and sex-matched controls with osteoarthritis (OA) and meniscal pathology were identified from the National Joint Registry and the Hospital In-Patient Enquiry (HIPE), respectively. The MRIs were reviewed by two musculoskeletal radiologists who were blinded to the clinical details. They were asked to assess the MRIs to determine PCL integrity, synovial Inflammation, and any associated pathology. Results No difference was noted in the rate of synovitis, PCL attenuation, or PCL tears between the OA and inflammatory arthropathy groups (p > 0.05). Conclusions The results of this study show no difference in the integrity and continuity of the PCL in those patients for age- and sex-matched controls on MRI. This finding lends support to the use of CR total knee arthroplasty in patients with inflammatory arthropathy on biologic agents.