Description
Objectives: A) To evaluate clinical outcomes and safety of a combined single-step approach with a biomimetic multi-layered collagen-hydroxyapatite scaffold (CHAS) and Bone Marrow Aspirate Concentrate (BMAC) in the treatment of knee joint surface lesions (KJSLs). B) To identify predicting factors for postoperative improvements, considering the patients’ data (age, sex, body mass index), medical history (previous surgeries, lesion aetiology, symptoms’ duration), joint status (Chondropenia Severity Score – CSS, concomitant osteoarthritis according to Kellgren-Lawrence classification – K-L OA, lesion size and location), length of follow-up, surgical details (concomitant procedures, CHAS configuration), and BMAC cellular components (fibroblast colony forming units - CFU-F, total nucleated cells - TNC, red blood cells – RBC) as potential predictors.
Methods: The study was a retrospective therapeutic case series of prospectively collected data. Clinical investigational plan was approved by the National Medical Ethics Committee (permit No. 0120-14/2016-5), and written informed consent was signed by every enrolled subject. Treatment outcomes were followed clinically with Patient-reported outcome measures (PROMs), and by pursuing serious adverse events (SAE) and graft failures (GF). Pre- and postoperative PROMs values were compared to evaluate postoperative improvements. Patients’ demographics, medical history, lesion status and operative details were determined (Table 1.). Chondropenia severity score (CSS) was assessed intraoperatively, during the arthroscopy. Cellular parameters of the applied BMAC were analyzed with cell counting on hematology analyzer, flow cytometry and CFU-F assays. Multivariable regression models were applied to identify significant predictors of the treatment outcomes.
Results: At the mean follow-up of 54.2 (19.4) months, 78 (87%) enrolled patients returned their questionnaires with significant improvements of all PROMs (Table 2.). The GF rate was 4%. The main negative predictors for the postoperative outcomes were: longer pre-operative symptoms’ duration, previous surgeries, larger lesions, older age, and female sex. CSS and CFU-F number positively influenced some of the clinical results and safety (Table 3.).
Conclusions: CHAS augmented with BMAC proved as an adequate and safe approach for KJSLs treatment up to mid-term follow-up. CSS proved as a valid grading system that can help to estimate prognosis after KJSLs treatment and guide intraoperative decision making. CFU-F number, which represent mesenchymal stem/stromal cells (MSCs) with colony forming abilities, may influence the treatment outcomes, therefore further attention should be given to the intraoperatively applied products. The study aided to recognize additional aspects to be considered in the knee osteo-chondral treatment.
