2005 Scoliosis Research Society Asian Traveling Fellowship: report to the Education Committee.
Explore the source record for details and available documents.
Education, Medical, Graduate↗
Biomedical subjects
Donald P K Chan
Publications and source records attributed to Donald P K Chan.
An anatomical study comparing standard fluoroscopy and virtual fluoroscopy for the placement of C1-2 transarticular screws.
OBJECT: The authors sought to compare radiation exposure, surgical time, and accuracy of screw placement when using either standard fluoroscopy or virtual fluoroscopy for the placement of C1-2 transarticular screws. METHODS: Twenty-two C1-2 transarticular screws were placed in 11 cadavers in a randomized and alternating order by using either standard fluoroscopy or virtual fluoroscopy (fluoronavigation). The radiation time, procedure time, and accuracy of screw placement were recorded and statistically compared. A small but statistically significant reduction in fluoroscopy time was noted with the virtual fluoroscopy technique but the surgical times were similar between the two techniques. The incidence of noncritical and critical breaches (those at risk of causing a neurovascular injury) was not significantly different between the two groups. Careful analysis of the C1-2 anatomy in these specimens underscored the importance of placing the screw path in a maximally dorsal and medial portion of the C-2 isthmus to avoid injury to the vertebral artery and to maximize the bone purchase of the C-1 lateral mass. CONCLUSIONS: Although virtual fluoroscopy may represent a useful tool for transarticular screw placement, it does not supplant traditional surgical techniques and does not appear to lower the incidence of bone breaches that can occur when performing this demanding procedure.
Bone Screws↗
A cadaveric study comparing standard fluoroscopy with fluoroscopy-based computer navigation for screw fixation of the odontoid.
Although direct osteosynthesis of certain types of odontoid fractures may increase union and decrease the need for prolonged immobilization, screw fixation remains a technically demanding procedure. This study compares radiation exposure, surgical time, and accuracy of hardware placement using standard fluoroscopy versus computer-assisted fluoroscopy-based navigation ("virtual fluoroscopy") to assist with the placement of odontoid screws. Twenty-two cadavers were divided into two groups and underwent placement of a single odontoid screw using either standard fluoroscopic or virtual fluoroscopic guidance. Following screw placement, dissection of the C1-C2 segments was performed to assess accuracy. A significant reduction in fluoroscopy time was noted with the computer-based fluoroscopy technique, whereas the surgical time was not found to differ significantly between the techniques. No critical breaches (those risking neurovascular injury) were noted in either group, and the rate of noncritical breaches did not differ. The authors conclude that fluoroscopy-based virtual navigation appears to have a safety profile similar to standard fluoroscopy while allowing a reduction in radiation exposure.
Bone Screws↗
Multiple unstable cervical fractures with cord compromise treated nonoperatively: a case report.
STUDY DESIGN: The case of a 17-year-old boy who sustained an unusual pattern of multiple unstable cervical spine fractures with a spinal cord injury is presented. OBJECTIVE: To review the management and treatment of multiple unstable cervical spine fractures. SUMMARY OF BACKGROUND DATA.: Combined unstable cervical spine injuries are uncommon. Treatment of multiple-level cervical spine fractures remains controversial. METHODS: The case of a 17-year-old boy who sustained a ring fracture of the atlas, an atypical traumatic spondylolisthesis of the axis, bilateral pedicle fractures of C3 with significant anterior subluxation of C3 on C4, a C6 burst fracture, compression fractures of C7 and T1, and significant cord compression as the result of a motor vehicle accident is presented. RESULTS: The patient was successfully treated with an initial closed reduction using cervical traction for 1 week followed by placement of a cervical halo vest. The fractures healed successfully, and the patient regained near-normal neurologic function. CONCLUSIONS: Despite advances in the surgical treatment of cervical fractures and dislocations, nonoperative treatment with halo immobilization remains a viable option for selected complex injury patterns.
Adolescent↗