Introduction

Locking nail have considerably improved the treatment of long weight bearing bones. However, distal locking needs experience and may expose to radiations. Many methods have been proposed to facilitate distal locking and improve safety. Recently, an external distal targeting device adapted to the ancillary of the Long Gamma Nail has been proposed. We report our experience with this device through a comparative series of distal lockings. Aim of this work was to assess feasibility and advantages brought about with this targeting device when considering time or dose of irradiation.

Purpose of the study: Computed tomography is recommended for the preoperative work-up of joint fractures as it allows an optimisation of the access as a function of the injury. During the operation, 2D radiographic or fluoroscopic controls are still widely used. After one year’s experience, we evaluated the potential pertinence of using 3D reconstructions intraoperatively with a mobile isocentric fluoroscope (iso-C-3D).

Material and methods: All operations for which the amplifier was used were collected prospectively. The type of fixation as well as the details of the installation and measures taken intraoperatively were noted.

Results: At one year, intraoperative 3D reconstructions were made during 48 operations in 47 patients: fracture of the calcaneum (n=13), thoracolumbar spin (n=12), acetabulum (n=11), tibial condyles (n=9), odontoid (n=2), pelvis (n=1). The installation was habitual for the calcaneum and odontoid fractures. For the other localizations, use of a carbon plateau table facilitated good quality imaging for spinal and tibial condyle fractures; a carbon orthopaedic table was useful for acetabulum and pelvis fractures. With the intraoperative 3D reconstruction the surgeon was able to check the freedom of the canal after reduction and fixation. For the calcaneum fractures, reduction of the thalamic fragment was revised in one patient; in another, an intra-articular screw was replaced. One intra-articular screw stabilizing the posterior wall was also changed during an acetabulum fixation.

Discussion: During our first year of use, 3D reconstruction intraoperatively has allowed us to avoid three early reoperations (for two calcaneums and one acetabulum). Classical 2D imaging of these two localizations is difficult to interpret because of the spherical form of the hip joint and, for the calcaneum, the difficulty in obtaining quality retrotibial images. Quality images requires specific installation, limiting interference with metallic supports.

Conclusion: The results we have obtained in our first year of use of the ISO-C-3D amplifier has led us to generalise its use for percutaneous fixation procedures involving the acetabulum and the calcaneum.

Introduction: Preoperative use of tomodensitometry is a common practice when assessing fractures with intraarticular involvement, helping to determine the most appropriate surgical approach according to the lesions observed. To date, during the surgical procedure itself, radiographical or fluoroscopic controls still largely rely on two dimensions X rays. We assessed the possible benefits of intraoperative tridimensional reconstructions using mobile isocentric fluoroscopy (iso-C-3D) after one year of use.

Material and Methods: All the procedures where intra-operative tridimensional fluoroscopy was used were assessed prospectively for one year. The type of osteosynthesis as well as specific modalities of installation and therapeutic measures driven from analysis of the images were analyzed.

Results: During the first year of use, intraoperative tridimensional reconstruction had been carried out in 48 procedures in 47 patients. The region involved was calcaneus 13 times, thoracolumbar spine 12 times, acetabulum 11 times, tibial condyles 9 times, axis 2 times and pelvis one time. Installation was the same than usually performed in the cases of calcaneus and axis osteosynthesis. For the other localisations, obtention of good quality images was facilitated through the use of a carbon table for spine and osteosynthesis of the tibial condyles, and through the use of a carbon traction table for acetabular or pelvic fractures. Intraoperative tridimensional reconstruction allowed to check for freedom of the vertebral canal after reduction and osteosynthesis of the spine. in the cases of fracture of the calcaneus, reduction of one thalamic fragment was improved in one case and one intraarticular screw could be changed in another case. In the case of acetabular surgery, one screw stabilizing the posterior wall was found intraarticular on tridimensional reconstruction and could be changed before closure.

Discussion: Intraoperative tridimensional reconstruction, during its first year of use, allowed to avoid 3 early reinterventions (for 2 calcaneus and one acetabulum). Accurate interpretation of standard plain X ray in these two localizations is difficult because of the spherical shape of the hip joint and because good quality imaging, especially the retrotibial view, is hardly obtained intraoperatively in fractures of the cacaneus. When using tridemensional reconstructions, acquisition of good quality images has to be anticipated during the installation of the patient, limiting any interfereces with metallic supports to a minimum.

Conclusion: the results obtained over the first year of use of intraoperative tridimensional reconstructions with the ISO-C-3D encouraged the authors to generalize its use when performing osteosynthesis of the acetabulum or calcaneus as well as percutaneus osteosynthesis of articular fractures.