Device-Related Complications of the Coflex Interspinous Process Implant for the Lumbar Spine
Authors: Zang L. 
Published: May 2014

Introduction Coflex, a type of interspinous process implant, can provide intervertebral dynamic stability for surgical segments and relieve lumbocrural pain effectively. However, few studies have described the avoidance and therapeutic strategies of Coflex implant complications. Materials and Methods Coflex implant complications included intraoperative or postoperative spinous process fracture, aggravated postoperative lumbocrural pain, dislodgment, and malposition in this study. The complications were analyzed, and therapeutic strategies were applied according to the specific complication. The Visual Analogue Scale and Oswestry Disability Index scores were evaluated by using the paired-samples test of SPSS 12.0 Results Conservative treatment was provided to seven patients who experienced aggravated lumbocrural pain even though their devices remained in the correct position, and pedicle screw treatment was used as an alternative in four cases. The Visual Analogue Scale and Oswestry Disability Index scores showed evident improvement in these patients. The Visual Analogue Scale and Oswestry Disability Index scores of two patients who underwent revision also improved. Conclusion Coflex implants should be avoided in patients with osteoporosis, a narrow interspinous space and intervertebral coronal spondylolysis, or sagittal instability; furthermore, the device choice, depth of implantation, and clamping intensity should be appropriate. Conservative treatment can be provided to patients with symptoms if the device remains in the correct position; however, revisions and salvages should be undertaken with internal fixation of pedicle screws for patients with device malposition, intraoperative implantation failure, or device intolerance. Disclosure of Interest None declared References Richards JC, Majumdar S, Lindsey DP, Beaupré GS, Yerby SA. 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