The concept of dynamic stabilisation of the lumbar motion segment using an interspinous device was first introduced by Professor Jacques

The concept of dynamic stabilisation of the lumbar motion segment using an interspinous device was first introduced by Professor Jacques Sénégas in the 1980s. His original first-generation implant comprised a titanium interspinous process spacer to accommodate load sharing and to limit extension. This was combined with two Dacron bands that controlled flexion movements. In contrast with other forms of instrumentation, this design required no direct fixation to bone, eliminating the risks of screw loosening or failure. Furthermore, since all anatomically important structures were preserved, the procedure was entirely reversible and preserved the entire range of alternative surgical options such as disc replacement and fusion. The survivorship of these first-generation implants has been impressive. A retrospective study of 142 patients who underwent surgery in France between 1987 and 1995 revealed that the actuarial survivorship of the implant was 84.1% at 10 years. In contrast with usual survivorship behaviour, the rate of failure actually decreased very notably with the passage of time. Furthermore, unlike multi-level fusion constructs, patients who underwent instrumentation of two or more levels fared no worse than those with single-level procedures.