Saphenous vascular periosteal flap in prevention of bone bridge formation after epiphyseal plate injury: An experimental study / 中华显微外科杂志

ABSTRACT

Objective:To establish a model of epiphyseal plate injury in juvenile rabbits and explore the effect of periosteum flap with saphenous artery on preventing the formation of bone bridge after epiphyseal plate injury.Methods:From July 2017 to January 2018, 30 young New Zealand immature rabbit were randomly grouped into 3 groups (group A, B and C, with 10 rabbits per group). The blood vessels of knee joint were dissected and a periosteum flap with saphenous artery were designed. A model of distal femoral epiphyseal plate injury was established in immature rabbits with a 3.0 mm Kirschner wire on one side of the distal femoral epiphyseal plate as experimental side, and the other side of the distal femoral epiphyseal plate was assigned as control side. The injured epiphysis were prepared and described as follow: in experimental side of group A, a piece of periosteum with the same size as that in group C was resected and discarded. In experimental side of group B, a periosteal flap without vascular pedicle was filled in the injured area. And in experimental side of group C, a periosteum flap with saphenous artery was filled in the injured area. The length and varus angle of femur specimens of length and varus angle of femur specimens wihthin groups were measured at 24 weeks after surgery to evaluate the effect on bone growth in epiphyseal plate injury. The effect of the periosteum flap with saphenous artery on preventing a formation of bone bridge was assessed by section view of decalcified specimens, HE staining and toluidine blue staining. The measured data were expressed as Mean and standard deviation (Mean±SD), and data were compared within and between the groups using one-way analysis of variance (ANOVA). P<0.05 was considered as statistically significant. Results:The femur of experimental side of group A and B showed obvious short with valgus deformity compared with that of control side, and the difference of length and varus angle of femur specimens wihthin groups was statistically significant ( P<0.05). There were no significant differences in the length and valgus angle of the femur between experimental side and its control side in group C ( P>0.05). In experimental side of group A, there were bone bridges in the epiphyseal lesion area, with a clear boundary to the surrounding epiphyseal plate. In experimental side of group B, the periosteum flap in the injured area was absorbed, accompanied by the formation of a few pale white bone tissue, and with a clear boundary to the surrounding epiphyseal plate. In experimental side of group C, the lesion area was filled with milky white cartilage tissue with the same colour as the epiphyseal plate, and with an unclear boundary with the epiphyseal plate. HE stain and toluidine blue staining showed that the injured area of group A was filled with a large number of bone tissue, but no obvious cartilage tissue was observed. In group B, the area of lesion was filled mainly with fibrous tissue, with a small amount of bone tissue. In group C, a large number of hyaline cartilage tissues were formed along the tunnel of the injury area, and closely connected with the normal epiphyseal plate. Conclusion:Filling a periosteum flap with saphenous artery after epiphyseal plate injury can prevent the formation of bone bridge and prevent the affected limb form shortening and angulation.