Experimental study on mechanism of vertebral osteophyte formation

Objective:The purpose of this experimental study was to explore the mechanism of the vertebral osteophyte formation.Methods:An experimental model of cervical spondylosis in rabbits was established by resection of the cervical supraspinous and interspinous ligaments and detachment of the posterior paravertebral muscles from cervical vertebrae.Because of individual difference,The natural development procedure of the vertebral osteophyte formation could be seen with a microscope by dynamic observation.Results:The cartilage end-plate was divided into a growth cartilage layer and an articular cartilage layer.Vertebrae and discs from the 3-month control group rabbits showed normal structure.The changes of cartilage plates from the 3-monthe experimental group and the 8-month control group animals showed proliferation in peripheral articular cartilage.The osteophytes from the 8-monthe experimental group animals could be seen.The osteophyte obviously arised from proliferation,calcification and ossification of the peripheral articular cartilage.Conclusions: The vertebral osteophyte arises from proliferation of peripheral articular cartilage which undergoes cartilaginous osteophyte,and then changes into bony osteophyte through an endochondrqal calcification and ossification.