Purpose: Associating autologous chondrocytes with a biomaterial has the advantage of facilitating fixation of graft cells and simplifies reimplantation. To evaluate the feasibility, tolerance, and efficacy of the Cartipatch(r) product, we are conducting a phase IIb study.

Material and methods: Cartilage (200–500 mg) was harvested arthroscopically from the lateral borders of the trochlea in the intercondylar space of damaged knees. After enzymatic digestion, the freed chondrocytes were cultured in monolayer in presence of autologous serum. The number of cells needed to achieve a concentration of 107/ml were suspended in an aragose and alginate solution. Before gelification, the suspension was poured into pits to obtain grafts measuring 10, 14 or 18 mm depending on the configuration of the lesion identified by MRI and arthroscopy. A specific instrument set was used to prepare one or two cavities for press fit insertion of the grafts. The grafts were justapositioned in order to best cover the damaged area.

Nineteen patients aged 16–50 years with a single osteochondral lesion or osteochondritis dessicans involving the femoral condyle but who had no other knee anomaly were included in this trial. The graft was inserted via an arthrotomy. Patients were examined preoperatively then at 3, 6, 12 and 24 months after grafting. The main evaluation criteria was improvement in the IDCD score (ICRS item) at 24 months. Secondary evaluation criteria were MRI and arthroscopic aspect associated with biopsy of the repaired tissue performed at 24 months.

Results: The first interventions required less than one hour. Patients followed the rehabilitation protocol with passive mobilisation and progressive weight bearing with no particular problem. Tolerance was good (no inflammation, adherence).

Discussion: The operative time needed to implant the graft was greatly reduced compared with classical chondrocyte grafts. Furthermore, this technique eliminates the need for periosteum suture guaranteeing a more homogeneous cell graft.

Conclusion: This short-term evaluation of the first patients is very encouraging. The first results concerning the effectiveness of this product, Cartipatch(r) are expected in the upcoming months.