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Study DesignA retrospective analysis of 7 patients with traumatic rotatory atlanto-axial subluxation.Overview of LiteratureCases of traumatic rotatory atlantoaxial subluxation in children are difficult to be stabilized. Surgical challenges include: narrow pedicles, medial vertebral arteries, vertebral artery anomalies, fractured pedicles or lateral masses, and fixed subluxation. The use of O-arm and computer-assisted navigation are still tested as aiding tools in such operative modalities.PurposeReport of clinical series for evaluation of the safety of use of the O-arm and computed assisted-navigation in screw fixation in children with traumatic rotatory atlantoaxial subluxation.MethodsIn the present study, 7 cases of rotatory atlantoaxial traumatic subluxation were operated between December 2009 and March 2011. All patient-cases had undergone open reduction and instrumentation using atlas lateral mass and axis pedicle screws with intraoperative O-arm with computer-assisted navigation.ResultsAll hardware was safely placed in the planned trajectories in all the 7 cases. Intraoperative O-arm and computer assisted-navigation were useful in securing neural and vascular tissues safety with tough-bony purchases of the hardware from the first and only trial of application with sufficient reduction of the subluxation.ConclusionsSuccessful surgery is possible with using the intraoperative O-arm and computer-assisted navigation in safe and proper placement of difficult atlas lateral mass and axis pedicle screws for rotatory atlantoaxial subluxation in children.

Background:Percutaneous insertion of pedicle screws was developed as a minimally invasive alternative to the different open spinal procedures. Here, we determined the accuracy of percutaneous pedicle screw insertion.Methods:For 60 consecutive patients with thoracic/lumbar spine fractures, computed tomography (CT) studies were utilized to assess the accuracy of percutaneous pedicle screw positioning. A screw was identified as cortical encroachment if the pedicle cortex could not be visualized, while Frank penetration was defined if screw trajectory being located obviously outside the pedicle boundaries [e.g., subdivided as minor (<3 mm), moderate (3–6 mm), and severe (>6 mm)].Results:Sixty patients received 410 pedicle screws placed percutaneously. Of these, 294 screws (71.7%) were ideally placed inside the pedicle. Alternatively, 56 screws (13.6%: 18 cases) showed pedicle encroachment and 60 screws (14.6%: 23 cases) showed pedicle penetration, e.g., 38 (9.2%) minor penetration and 22 (5.3%) were malpositioned (4.8% moderate and 0.5% severe). New postoperative neurological symptoms were identified in two cases (3.3%), where severe screw penetration was identified.Conclusion:Percutaneous pedicle screw insertion in 60 patients receiving 410 percutaneously placed pedicle screws yielded 294 ideally placed, 56 showing pedicle encroachment, 60 (14.3%, 23 cases) exhibiting varying degrees of pedicle penetration, with 2 showing new postoperative neurological deficits (severe screw misplacement). Of interest, this technique proved to be more challenging in the thoracic spine. Larger series are needed to better establish the average rate of neurological injuries associated with percutaneous thoracic/lumbar screw misplacement.

The preferred treatment of a type II odontoid fracture is anterior odontoid screw fixation to preserve the cervical spine range of movement. This case report describes an unusual complication of guidewire breakage during anterior odontoid cannulated screw fixation for a 52-year-old patient who presented with a type II odontoid fracture after a motor vehicle accident. The distal segment of the guidewire was bent over the tip of the cannulated odontoid screw and broke off during guidewire withdrawal. The three months follow-up computed tomography examination of the cervical spine showed acceptable screw placement, good odontoid process alignment with incomplete fusion, and no migration of the fractured segment of the guidewire. It is recommended that the guidewire be withdrawn once the cannulated screw is passed through the fractured site into the odontoid process and a new guidewire be used in each surgical procedure instead of been reused to avoid metal stress fatigue that can result in easy breakage.

Study Design Case report. Objective The purpose of this work is to report the case of a giant cell tumor involving the second cervical vertebra in a pediatric patient. Surgical management included a combined posterior and anterior cervical approach. There has been no recurrence in 2 years of follow-up. Case Report A 13-year-old girl presented with scoliosis with incidentally lytic lesion involving the second cervical vertebra. The radiologic investigations and biopsy result indicated a giant cell tumor of the bone. A combined posterior and anterior cervical approach was performed to resect the lesion, reconstruct the spine, and restore stability. Two years of follow-up revealed no recurrence of the lesion with stable reconstruction of the spine. Results The lesion was surgically managed for excision and spinal fusion by combining a posterior occipitocervical arthrodesis with an anterior retropharyngeal cervical approach. The final histopathology result confirmed a giant cell tumor of the bone. Conclusions Giant cell tumor involving the second cervical vertebra is uncommon; this tumor can be managed surgically by using a combined posterior and anterior cervical retropharyngeal approach. The presented case was unique in terms of the tumor location, patient age, and surgical management.