Fig. 5A–L.

Arthroscopic and histologic assessments were performed before and after transplantation of synovial MSCs. Arthroscopic features for the cartilage in Patient 3 are shown (A) before treatment and (B) at 11 months; for Patient 4 (C) before treatment and (D) at 18 months; for Patient 5 (E) before treatment and (F) at 14 months; and for Patient 7 (G) before treatment and (H) at 12 months. (I) A histologic section of the repaired cartilage obtained after a needle biopsy at the center of the repaired cartilage in Patient 3 contained fibrous cartilage in the deep zone and fibrous tissue in the surface zone. (J) In Patient 4, the histologic section contained hyaline cartilage in the deep zone and fibrous tissue in the surface zone. (K) In Patient 5, the section contained hyaline cartilage in the deep zone and fibrous tissue in the surface zone, and (L) in Patient 7, the section contained hyaline cartilage in the deep zone (Stain, Safranin O and fast green; Bar = 1 mm).