Effect of Systemic D Vitamin Supplementation on The Treatment of Full Thickness Articular Cartilage Defects

Abstract

Although the articular cartilage is complex and thin structure it is crucial in the structure and function of the joint. Treatment of the articular cartilage injuries has an significant role in orthopedic practice. Nevertheless, to heal the damaged articular cartilage in hyaline cartilage has not yet been achieved. In this study it was aimed to evaluate not only the effects of vitamin D to the cellular and extracellular matrix components of the articular cartilage but also the effects of vitamin D in the healing of the damaged articular cartilage by the microfracture technique which is frequently used in the treatment of the articular cartilage injuries. In this study, twenty‐four 18‐months‐old New Zealand rabbits were divided into four groups based on the treatment modality. Standart full thickness articular cartilage defect was applied in the medial femoral condile of the right knee of the all rabbits in the experimental groups. In group 1, only cartilage defect was established. After cartilage defect, in group 2, microfracture technique was applied. In Group 3, vitamin D was supplemented. And in group 4 both microfracture technique and vitamin D supplementation was applied as a treatment method. All animals were sacrified after 16 weeks and were evaluated histologically by ICRS, O′Driscoll and Pineda scoring systems. It was not observed any improvement in the area of the tissue defect in group 1. In group 2, the recovery of the defected tissue was not pure hyaline cartilage character. It was in the fibrous cartilage structure. Moreover a few round cells resembling chondrocytes were observed especially in the deep part of the healing tissue within the fibrous matrix. In group 3, the healing tissue in the defect area was a fibrous matrix character and although most of the embedded cells in matrix were fibroblast character, the existence of cartilage‐like cells was also recognized. Fibrotic tissue was observed in the superficial part of the healing tissue in the cartilage defect area but also in the deep layer close to the bone hyaline cartilage‐like tissue repairing was detected. Even though all other groups were reached statistically significant better results compared with Group 1, hyalin‐like cartilage repair was observed in Group 4. But this repair degree could not reach statistical significance when compared with Group 2. As a result, in this study it was shown that the systemic vitamin D supplementation has a positive effect in the treatment of local full‐thickness articular cartilage defects in rabbits. We suggest that more comprehensive and further long term studies are necessary for better understanding of the effects of vitamin D on the articular cartilage defects.