Summary Statement

Patients with adolescent idiopathic scoliosis show clear signs of abnormal motor coordination between the long superficial paraspinal muscles and the deep rotators. These findings suggest an abnormal behavior of the deep rotator muscles at the concave side.

Purpose of the study

To compare safety and efficacy of cervical disc replacement (CRD) in single and multilevel DDD. Patients were followed up at 1, 3, 6, 12 and 24 months.

Following studies in 2007-08 comparing cervical discs devices, satisfaction and accuracy of operated and adjacent levels was observed with titanium devices. Patients were followed up and surgical assessments recorded.

MRI with 12 patients were first assessed for imaging quality. Two independent radiologists scored twice sagittal and axial T2 – weighted images using the Jarvik four point scale. Statistical analysis was performed on operated and adjacent levels and between devices. Length of surgery, blood loss, approach and time of exposure to radiation were recorded. Patients were followed up at two years.

BAGUERA C containing titanium metal allowed satisfactory visualization of the canal, exit foramina, cord and adjacent levels. PCM and PRODISC C visualization was significantly impaired at operated level and in both spinal cord and neural foramina. At adjacent levels, image quality was statistically poorer for those two devices. 6 patients were operated at C5-C6 and 6 at C6-C7. Mean age was 49. Approach was from the right, length of surgery and blood loss were: mean 46 min and 16.25 cc for BAGUERA C; mean 70 min and 27.5 cc for PCM and mean 63 min with 26.25 cc for PRODISC C. Exposure to radiation presented also significant difference between devices. Clinical outcomes reveal similar VAS and patient's satisfaction scores.

Titanium device with polyethylene allow for satisfactory monitoring with adequacy in the assessment of neural decompression. BAGUERA C surgical outcomes indicate potential benefits that may be related to technique and simplicity of implantation.

Introduction: It is commonly admitted that for any joint fracture in the human body, a perfect anatomical reduction before stabilization is the only manner to biomechanically restore a joint and avoid late complications by early mobilization allowance. But, there is no evidence of anatomical fracture reduction when using vertebroplasty or balloon kyphoplasty in case of traumatic vertebral compression fractures (VCF).

Materials & Methods: A new procedure was proposed using titanium permanent vertebral cranio-caudal expandable implants (VCCEI) in combination with PMMA cementoplasty. The procedure has consisted in two steps: first, reduce the fractured vertebral body under fluoroscopic guidance by expanding the implants and second, stabilize the vertebra in its reduced position using PMMA cement injection. The implants ability to reduce the fractured endplates was assessed within a prospective international clinical study enrolling 37 patients (Mean age: 53yo, 18F/19M). 40 VCF (34 single level and 3 double levels) were included in this series. Mean fracture age was 11 days at the time of surgery. To evaluate the anatomical restoration, a new 3D measurement method was developed using millimetric CT scans 3D reconstructions. Morphologic parameters such as vertebral kyphosis angle and endplate surface restoration were calculated and clinical parameters were monitored (VAS score monitoring, hospital stay duration).

Results: First results are showing that the VCCEI is able to reduce the fractured vertebra whatever is the type of fracture providing that it is still mobile. Both vertebral kyphosis angle reduction and endplate surface restoration were achieved: up to 92% improvement for vertebral kyphosis and up to 10,8mm height increase in the anterior part of a fractured endplate. Posterior wall displacements were negligible. Neither antepulsion nor retropulsion of broken fragments were observed. No postoperative complication was reported but minor asymptomatic cement leakages. Pain was significantly reduced at the same time and hospital stay was comparable to

Conclusion: This new procedure has demonstrated its clinical and radiological efficacy in achieving anatomical reduction of VCF as well as relieving pain. The unique design of this VCCEI allows the surgeon to apply controlled cranio-caudal forces to reduce the fractured vertebra according to the fracture type and thus optimize the way the fracture will be reduced. Providing that the technique allows for a good control of the way the reduction is performed, there is a new possibility to treat VCF as they should deserve.