Kasemkijwattana reported the results of autologous bone marrow stem cells implantation in two patients with large traumatic cartilage defects of the knee. Bone marrow stem cells were re-implanted into the defects with a 3D collagen scaffold. After follow-up at 30-31 months, clinical evaluation showed significant improvement. The arthroscopic assessment showed good defect filling, stiffness and incorporation into the adjacent cartilage (Kasemkijwattana et al., 2011)