Effects of free perichondrial graft replacement of epiphyseal cartilage on bone growth

Effects of human amniotic fluid on cartilage regeneration from free perichondrial grafts in rabbits

After the chondrogenic potential of free grafts of perichondrium was shown in several experimental studies, perichondrium has been used to reconstruct cartilage tissue in various clinical situations. This study investigates the effects of human amniotic fluid on neochondrogenesis from free perichondrial grafts in a rabbit model. Since this fluid contains high concentrations of hyaluronic acid, hyaluronic acid-stimulating activator, growth factors, and extracellular matrix precursors during the second trimester, it may have a stimulating effect on neochondrogenesis. Perichondrial grafts, measuring 20 x 20 mm2 were obtained from the ears of 144 New Zealand young rabbits and were sutured over the paravertebral muscles. The rabbits were randomly divided into three groups with 48 rabbits per group. In group 1, 0.3 ml human amniotic fluid, and in group 2, 0.3 ml saline were injected underneath the perichondrial grafts. Group 3 formed the control group in which no treatment was given. Histologically, neochondrogenesis was evaluated in terms of cellular form and graft thickness at 2, 4, 6, and 8 weeks after surgery. In group 1, the mature cartilage was generated quickly and the cartilage plate in this group was significantly thick and extensive when compared with groups 2 and 3 at 8 weeks ( p<0.05 ANOVA). In conclusion, our study shows that human amniotic fluid enhances neochondrogenesis from free perichondrial grafts. The rich content of hyaluronic acid and growth factors possibly participate in this result.

Effect of lyophilized heterologous collagen on new cartilage formation from perichondrial flaps in rabbits: an experimental study

New cartilage formation originated from perichondrium has previously been researched in many clinical and experimental studies. 1-6 After these studies, the use of perichondrium for the repair of cartilage defects has been used clinically when enhancing neochondrogenesis has been found to be of great value in decreasing the recovery period. Collagen is the major protein of whole connective tissue, and in vitro positive effects of collagen matrices on neochondrogenesis have also been studied before. 7-9 In this experimental study, in vivo effects of heterologous collagen sponge in perichondrial neochondrogenesis were examined in an animal model, and acceleration and enhancement effects were observed.

The influence of human amniotic fluid on the potential of rabbit ear perichondrial flaps to form cartilage tissue

Since several experimental and clinical studies demonstrated the chondrogenic potential of perichondrium, there has been great interest in examining factors that might promote neochondrogenesis from perichondrium. Human amniotic fluid contains hyaluronic acid, growth factors and extracellular macromolecules, and may, therefore, have a stimulating effect on cartilage regeneration. This experimental study investigated the effect of human amniotic fluid on cartilage regeneration from rabbit ear perichondrial flaps, using 96 ears of 48 New Zealand young rabbits. A perichondrial flap was elevated and a cartilage defect measuring 20 mm x 15 mm was created on the dorsum of each ear, then the perichondrial flap was sutured in place. The ears were divided into two groups according to the solution injected underneath the perichondrial flap. The right ears, which were injected with 0.2 ml human amniotic fluid, formed the experimental group, and the left ears, which were injected with 0.2 ml saline, formed the control group. Macroscopic and histological progression of neochondrogenesis were evaluated at 2, 4, 6 and 8 weeks after surgery. Macroscopically, the cartilage in the experimental group was generated quickly and had a similar appearance to the surrounding cartilage tissue, whereas in the control group minimal cartilage formation was observed at 4 weeks. Histologically, the neocartilage was significantly thicker in the experimental group than in the control group at 8 weeks (P < 0.05, Student's t -test). It can be concluded that human amniotic fluid enhances new cartilage formation from rabbit ear perichondrial flaps. The preventive effect of human amniotic fluid on scar formation and the rich content of growth factors and extracellular matrix precursors may play a role in this result.

Vascularized Fibular Epiphyseal Transplantation for Limb Salvage Following Bone Tumour Excision

Vascularized fibular transplantation has found wide application for long bone reconstruction in both congenital and acquired defects. However, in children the growth of these transplants is limited and requires the epiphysis if it is to be substantial. Also, the reconstruction of a joint is best achieved with autologus hyaline cartilage. Vascularized fibular epiphyseal transplantation, thus, may play a role in limb salvage procedures in children to both preserve joint function and facilitate long bone growth. The present paper discusses the history of vascularized epiphyseal transplantation both in the laboratory and clinical realm. In discussing its advantages and associated problems, special emphasis is directed at the vascular factors, the endocrine environment, the innervation, mechanical stressors, the recipient site and the donor site. Two case examples are presented to demonstrate the technique, the results and the long term outcome.