Herein we address, hyaline cartilage regeneration issue by engineering a synthetic biocompatible hydrogel scaffold capable to promote chondrogenic differentiation. In this study, the chemically crosslinked hydrogels consisting of synthetic peptides that have the collagen-like sequence Cys-Gly-(Pro-Lys-Gly)4 (Pro-Hyp-Gly)4 (Asp-Hyp-Gly)4- conjugated with RGD sequence (CLP-RGD) and crosslinked hydrogels of type I collagen (CA) were used. For cartilage formation, we used human skeletal muscle-derived stem/progenitor cells (hMDSPCs) set for differentiation towards a chondrogenic lineage by BMP-7 and TGF-ß3 growth factors.

Initially 150, 100 and 75 ng of BMP-7and TGF-ß3 growth factors were inserted in each scaffold and amount of growth factors diffusing out of the scaffolds was observed by ELISA assays. In vitro experiments were performed by seeding hMDSPCs onto hydrogels loaded with growth factors (75ng/scaffold) and cultured for 28 days. Cartilage formation was monitored by ELISA and RT-PCR assays. All experiments were performed in triplicates or quadruplicates.

Growth factors incorporation strategy allowed a sustained release of TGF-ß3 growth factor, 6.00.3% of the initially loaded amount diffused out after 4 h and 2.70.5% already at the second time point (24h) from CA and CLP-RGD substrates. For the BMP-7 growth factor, 13.12.3% and 15.751.6% of the initially loaded amount diffused out after 4 h, 1.70.2% and 2.450.3% at the second time point (24 h) from CA and CLP-RGD respectively. In vitro experiments shown that scaffolds with immobilized growth factors resulted in higher collagen type II accumulation when compared to the scaffolds alone. The gene expression on CLP-RGD hydrogels with growth factors has shown lower collagen type I expression and higher aggrecan expression compared to day 0. However, we also report increased collagen X gene expression on CA hydrogels (with growth factors).

Our results support the potential of the strategy of combining hydrogels functionalized with differentiation factors toward improving cartilage repair.

Aim: The aim of the current study is to investigate if viscosupplemetation therapy will increase the effect of microfracture technique by acting the quality and quantity of the new cartilage after microfracture.

Material and Method: Full thickness chondral defects were created to intercondylar notch as a nonweightbearing area by using a handle drill bit. Microfracture holes between bridges were performed with a 1mm K wire.

The present study was performed on 30 mature white rabbits (male range, 2800–3500 gr). The right knees were accepted as study and left knees as control group. Group 1 was received intraarticular 0.1ml sodium hyaluronate treatment, rabbits in group 2 were received 0.1 ml Serum Physiologique once a week for three weeks. Biopsy was taken from both knees at the 3rd and 6th week. Histopathological evaluation was performed by a pathologist who is blind to study according to modified Mankin score.

Results: Although the difference of the scores between study and control group was not statistically different at the third week, it was seen different at the sixth week histologically.

Conclusion: Hyaluronic acid may be benefecial in the treatment of chondral lesion addition to arthroscopic microfracture technique.