6.1.2 Preparation of SVF for implantation The syringes with subcutaneous aspirate are prepared using the Lipogems system. The Lipogems system is an enzyme-free technology developed to process variable amounts of lipoaspirates in a closed system, resulting in a nonexpanded adipose tissue product that contains SVF. The technology works through a mild mechanical tissue cluster size reduction. Thereby avoiding the use of any enzyme and additional processing (i.e., centrifugation and subfractional harvesting).13 6.1.3 Implantation of SVF Implantation of the SVF is done under sterile conditions in the outpatient clinic. The patient is positioned supine on an examination bench with the affected knee stretched. The superior pole of the patella is palpated and the femoral condyle is marked with a surgical marker. The suprapattelar recess is located by ultrasound, local anesthesia is applied to the injection site and surgical cleaning is performed twice. Injection of the SVF in to the suprapattelar recess is done using a 21 gauge syringe under direct visualization by ultrasound. At the end of the procedure the skin is closed with a plaster.