Navigating the New EU Medical Devices Regulation: Retrospective Post-Market Follow-Up of Hyaluronic Acid Injections for Knee Osteoarthritis

Purpose: The entry into force of the new Medical Device Regulation (EU) 2017/745 highlights the need for post-market clinical follow-up to ensure the safety and efficacy throughout the life cycle of medical devices. This study evaluates the efficacy and safety of a single intra-articular hyaluronic acid injection in knee osteoarthritis in real-world conditions, over a six-month period, aligning with the summary of safety and clinical performance (SSCP) required by the new regulation. Patients and Methods: Patients over 18 years of age with knee osteoarthritis, treated with a single injection of HA (Adant ® One, Meiji Pharma Spain, Spain) at a 3rd level hospital. Patients were treated and followed between January 1, 2020 and June 30, 2022. Demographic, clinical, and treatment-related data were collected, and efficacy regarding pain relief and/or function improvement was assessed using a Likert-type scale. Data were pseudo-anonymized and the comparison was performed using Fisher’ or Mann Whitney’ test. The study was approved by the Ethics Review Board of the Hospital Puerta de Hierro (Madrid, Spain). Results: We followed 20 patients with knee osteoarthritis, with a mean age of 61 years, 80% women, and with a high burden of comorbidities (90%). A total of 60% of patients presented Kellgren-Lawrence grade III–IV. Four patients (20%) returned before 6 months due to lack of efficacy. Of the other patients, 65% showed a clinical response that lasted more than 12 months in 38.5% of cases. Time until medical appointment and taking concomitant medication for knee osteoarthritis were associated with better clinical response (p < 0.05). Conclusion: The administration of a Adant ® One single intra-articular hyaluronic acid injection in knee osteoarthritis is effective, safe, and maintains the improvement over a six-month period. Our findings also emphasize the need of using standardized tools for accurate efficacy assessment and optimal patient care.