Efficacy and Tolerance Study of B-DYN Versus Conventional Fusion in the Treatment of Lumbar Stenosis on the Degree of Post-operative Functional Incapacity (BDYNCLIN)

The surgical technique for placement of the B-Dyn device is performed under general anaesthesia. The procedure begins with the insertion of the first upper polyaxial screw which is screwed in with the polyaxial screwdriver. The use of the phantom (Trial 10) is necessary in order to position the second screw. Once the screws are positioned, the B-Dyn is taken between the jaws of the gripping forceps in order to insert it into the heads of the polyaxial screws. The movable rod of the B-Dyn is then placed in the head of the upper screw. The positioning mark of the fixed rod must be placed facing the operator and in the center of the lower screw head. Finally the cap of the lower polyaxial pedicle screw is tightened. A final tightening of the two plugs on the polyaxial pedicle screw heads is performed to fix the assembly.

The surgeon will complete his gesture by placing 2 screws in the upper vertebra and 2 screws in the lower vertebra; the screws will be connected to each other to stabilize the assembly. This type of surgery is done via posterior approach and under general anaesthesia.