Inclusion Criteria:  Subject is at least 18 years and maximum 50 years of age at time of surgery; Subject presents with a symptomatic defect in the knee with an NRS pain score of 4 or more; Subject presents with defects in the knee cartilage with ICRS classification grades IIIa or IIIb; Subject has a contained lesion of between 0.5 - 2 cm2 in size, and it is localized on the femoral condyle or trochlea; Subject has an intact (ICRS grade ≤ 1) articulating joint surface (without "kissing lesions"); Subject is willing and able to comply with all aspects of the treatment, including MRI, after-care rehabilitation and evaluation schedule over a 12-month duration; and Subject is willing and able to provide documented Ethics Committee-approved informed consent prior to initiation of any study procedures.  Exclusion Criteria:  Subject has a BMI > 30 kg/m2; Subject has multiple defects to be treated that are interconnected or that have less than 0.5 cm of space in between them; Subject underwent index-knee surgery < 3 months prior to study treatment.  Subject suffers from any medical condition that would hinder cartilage repair, such as additional unresolved comorbidities related to the index knee:  Untreated anterior cruciate ligament (ACL) and/or posterior cruciate ligament (PCL) deficiency or, Complex ligamentous instability of the knee/ insufficient ligament support, Meniscus lesions, total or partial (more than 1/2 of total volume) resected meniscus, Limited joint mobility, Varus/valgus joint malalignment of more than 3 degrees, Subject has a trochlear cartilage defect that is associated with (suspected) patella maltracking without surgical correction, Subject underwent previous (failed) cartilage repair procedure(s), such as microfracture (MF), Osteochondral Autograft Transplantation (OATS) or Autologous Chondrocyte Implantation (ACI) with or without use of a scaffold (matrix) in the index knee.  Comorbidities that are resolved during the same surgical procedure as the investigational device treatment, do not qualify for this exclusion criterion.  Subject has (history of) generalized osteoarthritis, defined as Kellgren-Lawrence grade >1 as determined from recent (<6 months at time of enrollment) X-ray; Subject suffers from inflammatory joint diseases (e.g. rheumatoid arthritis, Bechterew disease, chondromatosis); Subjects suffers from autoimmune disease, vascular or neurological disease; Subject suffers from an active or recent local or systematic infection, or has a history of knee infections; Subject has an active malignant tumor at the time of treatment; Subject has hypersensitivity or allergy to the constituents of the product. Pregnant or lactating women at the time of enrollment or women who are planning to become pregnant during the duration of the study.