Different Interspinous Stabilization Systems: Market Evaluation
The interspinous spacers are those devices that placed between the spinous processes of contiguous vertebrae, act by dynamically stabilizing the vertebral segment in the sagittal plane. The principle of implanting a spacer between adjacent spinous processes was used by F. Knowles in the 1950s to discharge the posterior ring in patients with herniated discs and thus achieve pain relief [1,2]. Senegas et al.  who in 1986 designed a system of dynamic normalization stabilization (mechanical normalization system) to stiffen the degenerated lumbar segment operated, using an interspinous titanium block to limit the extension and a tension band (Dacron) around the spinous processes, to Secure the implant and limit bending. This implant, which was designed as the first generation of the current Wallis, so that it restored more physiological mechanical conditions in the treated degenerate segment, could not only alleviate or prevent the pain related to instability but decrease the range of disc destruction at that level. It was also suggested that if the interspinous stabilization system preserved more mobility in the treated segment than a fusion would do, then the degenerative process at adjacent levels would progress more slowly [4,5].