PMC

Case 4: arthroscopic view of the knee 12 mo postoperative, with the arthroscopic probe pointing to grossly appearing, smooth, hyaline-like repair tissue completely filling the defect.

Autologous mesenchymal stem cell (MSCs) platelet-rich fibrin glue (PR-FG) implantation. (a) Cartilage defect curetted to a peripheral stable rim of cartilage and subchondral bone drilled. (b) Periosteal flap harvested from the proximal tibia. (c) Defect covered with periosteal flap, sutured, and then sealed with fibrin glue. (d) MSCs mixed with PR-FG intraoperatively to be introduced through the 12 o’clock position of the defect.

Mean clinical scores: preoperative (dark gray column), 6 mo postoperative (light gray), and 12 mo postoperative (black). (a) Lysholm (Lysh) scores 6 mo (Lysh 6M) and 12 mo (Lysh 12M) postoperative were statistically different (*) from preoperative scores (P < 0.05). The mean 6 and 12 mo postoperative Lysholm scores improved from 41.2 ± 13.14 preoperatively to 81.6 ± 11.93 at 6 mo (P = 0.042) and 86.0 ± 9.25 at 12 mo (P = 0.042). (b) Revised Hospital for Special Surgery Knee (RHSSK) scores 6 mo (RHSSK 6M) and 12 mo (RHSSK 12M) postoperative were also statistically different (*) from preoperative scores (P < 0.05). The mean 6 and 12 mo postoperative RHSSK scores improved from 53.8 ± 15.39 to 79.0 ± 11.77 at 6 mo (P = 0.043) and 83.8 ± 9.78 at 12 mo (P = 0.043). No statistically significant difference was found between scores at 6 and 12 mo postoperative (P = .18).

X-rays of case 1 and 4. (a) Preoperative AP radiograph of the knee of case 1 showing medial femoral condyle osteochondral erosion (black arrow), narrowing of the medial joint line, and osteophyte formation. (b) Preoperative AP radiograph of the knee of case 4 showing preserved joint line with no radiographic evidence of advanced degenerative joint changes. The patient had an osteochondral lesion in the lateral femoral condyle that was apparent on magnetic resonance imaging (see ) and radiographic tunnel views.

Magnetic resonance image (MRI) of sample case 4. (a) Preoperative sagittal magnetic resonance imaging (MRI) proton density sequence (PD) showing an osteochondral lesion (white arrow) in the lateral femoral condyle. This lesion was found to be completely detached on arthroscopy performed during bone marrow aspiration. (b) Sagittal MRI (PD) at 12 mo postoperative showing isointense signal of the repair cartilage (white arrow) compared with the native cartilage, complete filling of the defect, congruent surface of the repair cartilage, no delamination, and no subchondral bone marrow edema.