Experimental Study Of Developing Safe-control Device In Posterior Vertebral Column Resection For The Treatment Of Severe Rigid Spinal Kyphosis

Background:Not only the quality of life in severe spinal kyphosis patients declined seriously, but paraplegia of late-onset occurred very commonly. If the severe spinal kyphosis located the thoracic vertebral columns, the patients may die for whose respiratory and circulatory functions limited. And, kyphosis usually is progressive without surgical intervention. However, current recommended treatment includes spinal osteotomy is with significant trauma, and the incidence of neural complication is still very high. There were reports about intra-operative spinal cord monitoring used to reduce the incidence of neurologic complication successfully. Surgeons could find the abnormal intra-operative neurogenic monitoring evoked potentials early by intra-operative spinal cord monitoring and correct the surgical factors caused impermanent damage. Theoretically, intra-operative spinal cord monitoring can't avoid occurrence of neurologic damage, but can avoid its aggravation and sustain. So, research about avoiding occurrence of neurologic damage has clinical contribution. Spinal subluxation and over-shortening of spinal cord were regarded as the two main mechanisms of neurologic complication. There were no reports about to control the two main mechanisms by devices, although they can be controlled by devices.Objective:To investigated risk factors of spinal osteotomy of severe spinal kyphosis patients through the retrospective case-control study, and which were based on to design posterior spinal osteotomy safe-control device.Methods:To investigate the risk factors included age, gender, diagnosis, preoperative and post-operative saggital Cobb's angle, resected vertebra, correction rate, preoperative and postoperative distance of anterior margin of the vertebra, preoperative and postoperative distance of posterior margin of the vertebra, prolonged rate of postoperative anterior margin of the vertebra, shortened rate of postoperative posterior margin of the vertebra, preoperative and postoperative nerve function, difference between distance of anterior and posterior margin of the vertebra, estimate blood loss, surgery time of patients who were treated by posterior-only spinal osteotomy through the retrospective case-control study. And analysis the risk factors through statistics software. Then design posterior spinal osteotomy safe-control device base on the risk factors which had statistical differences.Results:1. There were significant differences between normal neurologic function groups and declined neurologic function group in terms of age, postoperative distance of posterior margin of the vertebra, prolonged rate of postoperative anterior margin of the vertebra, shortened rate of postoperative posterior margin of the vertebra, difference between distance of anterior and posterior margin of the vertebra, estimate blood loss, (P <0.05).2. Logistic regression analysis was used to acquire equation:Y=1.926Xi-0.001 X2+10.8, the X1 is the difference between distance of anterior and posterior margin of the vertebra and the X2 is estimate blood loss.3. Safe-control device in posterior spinal osteotomy was designed.Conclusions:Severe rigid spinal kyphosis was only treated by posterior spinal osteotomy with neurologic complications frequently. There are no particular devices to reduce the risk. We studied post-operation patients to find the factors that affected the neurologic safety and to produce a device to control them.