Development Of Traction Exercise Neck Brace And Its Mechanism Of Action On Cervical Spondylotic Radiculopathy

Objective:Cervical spondylotic radiculopathy(CSR)accounts for about 60%-70%of all types of cervical spondylopathy.Cervical traction is an important non-surgical approach.Basing on the guidance of the theory of traction rehabilitation for CSR,a traction exercise neck brace(TENB)was developed.Clinical trials were conducted to study the effect of TENB on CSR subjects,and analysis the effect of traction intervention on cervical-vertebra.The biomechanical effect of TENB on CSR was studied by finite element analysis.In the present study,the effect and mechanism of the clinical indications of TENB were clarified through its design and development,clinical trials,and biomechanics analysis.Methods:(1)According to design concept of cervical traction weight,time and angle,and design principle of clinical safety,effectiveness and good patient compliance,the TENB was developed after 6 times of design conception and program evaluation.(2)Twenty CSR volunteers were recruited in Wuyi hospital of traditional Chinese medicine in Jiangmen city.Static traction and cervical muscle resistance exercises were performed for 30 minutes with TENB,twice a day for 4 weeks.Clinical symptoms were evaluated by overall evaluation,JOA score,VAS score and NDI score.Borden and CCI measurements were used to evaluate the physiological curvature of the cervical spine,and three-dimensional reconstruction of CT images of the cervical spine was performed to measure the area of the intervertebral foramen.(3)CT image data of the neck of subjects with typical CRS were collected,and the finite element model of the cervical spine in all segments was obtained through 3D reconstruction.The force analysis was carried out in the head and neck bending forward 20°in different traction line directions(inclining forward 20°,10°,neutral 0°,inclining backward 10°,15°).Results:(1)TENB was composed of upper and lower supports,and traction and exercise structures.Upper support was fixed on the mandible and occipital bone and the lower support was fixed on the shoulder.After fixation,exercising the neck muscles by manual traction,forward flexion and back extension.The traction stroke was changed 0-35 mm.The range of traction line is 25° forward to 15° backward,and the range of head and neck position change is 20° forward to 45° backward.It could also give combination with cervical fixation and resistance exercise.(2)In clinical studies,TENB significantly reduced the overall score,JOA score,VAS score and NDI score of subjects with CSR,suggesting an improvement in the clinical symptoms of CSR.After treatment,the measured parameters of Borden and CCI increased by 46.54%and 36.21%respectively,indicating an improvement in the physiological curvature of cervical vertebra.The treatment mainly increased the area of intervertebral foramen at C4-C5 and C5-C6 levels,and the increase on the left side was greater than that on the right side.(3)According to the finite element analysis,simulated traction can increase the upper and lower diameter of the intervertebral foramen and increase with the increase of traction angle.Traction increases the interarticular space of the facet,reduces the interarticular space of the uncinate vertebra,and traction increases the stress of the lower cervical facet.The anterior intervertebral disc spacing followed the changes in the anterior to posterior traction lines,and the posterior intervertebral disc spacing tended to be opposite to the anterior intervertebral disc spacing.Traction increases the maximum tensile and compressive stresses of the disc nucleus pulposus.Conclusions:This study successfully developed a TENB.The product has three functions includes functions of neck fixation,effective traction and resistance exercise,which processes good safety and compliance.TENB can significantly relieve the clinical symptoms of CSR,adjust the physiological curvature of cervical vertebra.improve the area of intervertebral foramina,adjust the stress distribution of cervical vertebra,and restore the normal physiological bending and biomechanical characteristics.Basing on the product development,clinical trial and biomechanical analysis,this study revealed the effect of TENB on CSR and provided theoretical basis for its clinical effect.