Pedicle Screw-based Dynamic Stabilization with a Hinged Screw Head System in the Treatment of Lumbar Degenerative Disorders

Yang, Jin Seo; Heo, Dong Hwa; Kang, Suk Hyung; Cho, Yong Jun

Abstract

OBJECTIVE
Lumbar dynamic stabilization systems have been developed for the treatment of lumbar degenerative diseases. However, the clinical results of dynamic stabilization systems are still not well established. The purpose of this study is to assess the clinical and radiologic outcomes of lumbar dynamic stabilization using a hinged screw head system(Cosmic(R)).
METHODS
Eighteen patients were followed for more than 1 year after dynamic stabilization with the Cosmic system. The following parameters were reviewed: age, sex, visual analog scale (VAS) for the leg and back, the Oswestry Disability Index (ODI), complications related to the operation, range of motion (ROM) of the adjacent segments, implantation segment and the whole lumbar spine. We compared the preoperative ODI, VAS, and ROM of the adjacent segments, implantation segment and the whole lumbar spine with the 1-year postoperative follow-up results.
RESULTS
The mean preoperative ODI and VAS scores were significantly decreased after the operation (p<0.05). ROM at both the cranial and caudal adjacent segments did not change significantly postoperatively (p>0.05). The mean preoperative ROM of the implantation segment was decreased postoperatively. However, the mean ROM of the whole lumbar spine did not change significantly postoperatively (p>0.05).
CONCLUSION
According to our preliminary results, lumbar dynamic stabilization using a hinged screw head system did not influence adjacent segment motion, and had improved clinical outcomes for a 1-year postoperative follow-up period.