Two-stage bone and meniscus allograft and autologous chondrocytes implant for unicompartmental osteoarthritis: midterm results.

BACKGROUND: We analyzed the clinical and radiographic evolution of patients with knee unicompartmental osteoarthritis and axis alteration and osteochondral lesions in the femoral condyle, treated with tibial plateau and meniscus allograft and cultured autologous chondrocyte implantation in the femur in two steps. PURPOSE: To analyze the clinical results with the first patients treated with this two-stage technique to avoid knee prosthesis in patients with unicompartmental osteoarthritis. MATERIAL AND METHODOLOGY: Sixteen patients, average age 56 years, were included in a cohort study. We performed an osteotomy with tibia plateau allograft, including the meniscus. In a second surgery, the chondrocyte fibrin scaffold was placed in the femur. Clinical symptoms and function were measured using KSSR and KOOS scores. Wilcoxon's test was performed to compare the results over the 2-year follow-up period. RESULTS: Mean KSSR before surgery was 35.69 (SD: 3.75) points, rising to 67 (SD: 15.42) at 3 months, 95.88 at 12 months (SD: 2.68) and 96.31 at 24 months (SD: 2.24). The KOOS before surgery was 65.14 (SD: 16.34), rising to 72.68 after 3 months (SD: 19.15), 76.68 at 12 months (SD: 18.92) and 64.28 at 24 months (SD: 11.79). Four of 5 patients returned to engaging in the activity that they had stopped practicing. Three patients experienced collapse of the tibia allograft, and they needed later a prosthesis. CONCLUSIONS: Simultaneous tibia plateau allograft and autologous chondrocyte implantation in the femur, after correction of the angular deformity, were performed, restoring the anatomy of the medial compartment and knee function in 82% of the patients 2 years after the operation. LEVEL OF EVIDENCE: IV.

Cotransfected human chondrocytes: over-expression of IGF-I and SOX9 enhances the synthesis of cartilage matrix components collagen-II and glycosaminoglycans

Damage to cartilage causes a loss of type II collagen (Col-II) and glycosaminoglycans (GAG). To restore the original cartilage architecture, cell factors that stimulate Col-II and GAG production are needed. Insulin-like growth factor I (IGF-I) and transcription factor SOX9are essential for the synthesis of cartilage matrix, chondrocyte proliferation, and phenotype maintenance. We evaluated the combined effect of IGF-I and SOX9 transgene expression on Col-II and GAG production by cultured human articular chondrocytes. Transient transfection and cotransfection were performed using two mammalian expression plasmids (pCMV-SPORT6), one for each transgene. At day 9 post-transfection, the chondrocytes that were over-expressing IGF-I/SOX9 showed 2-fold increased mRNA expression of the Col-II gene, as well as a 57% increase in Col-II protein, whereas type I collagen expression (Col-I) was decreased by 59.3% compared with controls. The production of GAG by these cells increased significantly compared with the controls at day 9 (3.3- vs 1.8-times, an increase of almost 83%). Thus, IGF-I/SOX9 cotransfected chondrocytes may be useful for cell-based articular cartilage therapies.