Objective: To study project of simplicity and utility for screw-plate system by pedicle of atlanto-axis manipulatively hand by X-ray film and CT to prove the one success rate of putting screws.
Methods: Formulate personal program was used in operation by image save transmission of X-ray film and CT during January 2002 and September 2006 in 31 patients. There were 18 males and 13 femals, aged from 23 to 61 years old withan average age of 43.5 years. Putting screw points by pedicle of atlas were measured: left (19.93 +/- 1.32) mm, right (19.16 +/- 1.30) mm; putting screw obliquity angle to inside by pedicle of atlas: left (23.72 +/- 2.09) degrees, right (23.35 +/- 1.91) degrees; putting screw obliquity angle to side of head by pedicle of atlas: (9.00 +/- 1.20) degrees. Screw points by pedicle of axis: left (13.14 +/- 0.82) mm right (13.85 +/- 0.79) mm; putting screw obliquity angle to inside by pedicle of axis: left (24.52 +/- 1.26) degrees, right (20.42 +/- 1.42) degrees; putting screw obliquity angle to side of head by pedicle of axis: (25.00 +/- 3.00) degrees. The domestic location toward speculum was employed in operation and putting screw points and angles were formulated by X-CT program. The pedicle screws of suitable diameter and length were of exception and screws into pedicle of atlanto-axis were put by hand.
Results: Pain of the greater occipital nerve occurred in 2 patients after operation and was fully recovered by treatment 1 month after operation. The lateral cortical bone of pedicle was cut by 2 screws, but the spinal cord and vertebral artery were fine. The atlas and the fracture of odontoid process of axis were completely replaced in X-ray films of all patients 1 day after operation. The position relation of lag screw and vertebral artery or spinal cord was very good in CT sheets. All cases were followed up with an average of 10.5 months during 9 months to 5 years and 4 months,and obtained atlantoaxial arthrodesis. The breakage of screw and plate was not found in all cases. According to JOA score standard, 16 cases were excellent, 12 were good, 2 were fair, 1 was poor, and the excellent and good rate was 90.32%.
Conclusion: The personal design and clinical application of X-ray films and CT sheets are of great significance to screw-plate system by pedicle of atlanto-axis because of simplification of designs and methods and better personality.