Changes in the Immunomodulatory Properties of Adipose Stromal Cells Due to Hemarthrosis After Knee Injury

The goal of this observational study is to gain insight in the natural course of pro-inflammatory factors and hemarthrosis in patients older than 18 with a recent knee trauma. The main question[s] it aims to answer are:What is the natural course of pro-inflammatory factors and hemarthrosis in knee trauma?What are the effects of inflammation and hemarthrosis on the anti-inflammatory potential of ASC's in order to better determine eligible patients and circumstances for ASC's therapy?Participants will:undergo blood withdrawalundergo knee arthrocentesis for synovial fluid sample collectionphysical examinationfill out a questionnaire on knee complaints

Inclusion Criteria:Recently suffered an injury of the index knee (rotational or hyperextension)A swollen jointInability to mobiliseExclusion Criteria:Patients with an active inflammatory or infectious comorbid disease (including rheumatic diseases)Patients using systemic immunosuppressant medicationPatients with a contra-indication for undergoing a MRI-scan (non-compatible implants or claustrophobia for example)Patients with knee prosthesisPatients with coagulation disordersPatients with a history of a cruciate ligament or meniscal injury of the index kneePatients with a tibiofemoral fracture of the index knee due to current distortionIn case the inclusion of the required amount of patient is reached in one the patient groups, additional patients belonging in the same patient group will not be included in the study