The same group treated an articular cartilage defect in the weight-bearing area of the medial femoral condyle with autologous bone marrow stem cells prepare in the same manner in a patient. Seven months after surgery, arthroscopy revealed the defect to be covered  with smooth tissue. Histologically, the defect was filled with a hyaline-like type of cartilage tissue, which stained positively with  Safranin-O. One year after surgery, the clinical symptoms had improved significantly. The patient had re-attained his previous activity level and experienced neither pain nor other complication (Kuroda et al., 2007)