[An imaging study on location of the anterior border of facets and the posterior border of vertebral bodies in lower cervical spine].

OBJECTIVE: To explore the location of the anterior border of facets and the posterior border of vertebral bodies in lower cervical spine,and to provide a quantitative data to evaluate the correct length of transarticual screws in lower cervical spine during procedure. METHODS: One hundred standard lateral X-ray films and fifty CT films on cervical spine were used to measure the distance of the anterior border of facets and the posterior border of vertebral bodies in lower cervical spine. HS, HM and HI were defined as parameters, which means the distance between the anterior border of the superior (HS), median (HM) and inferior (HI) part of facets and the posterior border of corresponding vertebral bodies. The value will be negative if the anterior border of the facet located before the vertebral body. RESULTS: 'HS > HM > HI' was found in all facets in lower cervical spine. The anterior border of the facet in C(3,4) located before the posterior border of the vertebral body of C3. The anterior border of C(4,5) and C(5,6) was inclined to posterior. The anterior border of C(6,7) located after the posterior border of the vertebral body of C6. The pattern of HS increased from C(3,4) to C(6,7), the minimal (0 +/- 0.25) mm and the maximal (2.91 +/- 1.05) mm. The tendency of HM raised from C(3,4) to C(6,7), the minimal (-1.57 +/- 0.53) mm and the maximal (1.54 +/- 0.39) mm. The pattern HI added from C(3,4) to C(6,7), the minimal (-2.03 +/- 0.40) mm and the maximal (1.08 +/- 0.70) mm. CONCLUSION: During the implantation of the transarticular screws, the tip of the screws should be 0-2 mm before the posterior border of the vertebral body of C3 at C(3,4), 0-2 mm after that of C4 at C(4,5), 0.5-2.5 mm at C(5,6) and 1-3 mm at C(6,7). The quantitative location between the anterior border of facets and the posterior border of the corresponding vertebral bodies can offer an indirect method to evaluate the correct length of transarticual screws in lower cervical spine during procedure.

[Analysis of complications in scoliosis surgery].

OBJECTIVE: To analyze the complications occurred in scoliosis surgery and evaluate its prevention strategy. METHODS: From June 2002 to May 2007, 86 cases of idiopathic scoliosis were treated. There were 21 male and 65 female with an average age of 17.8 years(range, from 8 to 22 years). According to Lenke classification, 33 cases were type 1, 10 type 2, 18 type 3, 5 type 4, 10 type 5 and 10 type 6. Five cases were Risser 0 to I, 20 cases II to III, 61 cases 1V to V. Cobb angles were from 45 degrees to 85 degrees (mean 60.35 degrees). The pedicle screw technique was used to correct all the scoliasis, and the results and complications were studied. RESULTS: The average operation time was 3.2 hours and average blood loss volume was 1000 ml (800-2400 ml), 924 pedicle screws were inserted and the average postoperative Cobb angle was 18.46 degrees. All the patients were followed up for 5 to 40 months(mean 20.5 months). The complications were as following: 1 case of spinal cord injury; 25 screws misplaced; 2 cases of nerve root injury; 1 case of pleura injury; 1 case of superior mesenteric artery syndrome; 3 cases of wound infection; 2 cases of trunk decompensation; 1 case of junction kyphosis; 3 cases of implant loosening; 2 cases of pseudarthrosis; 1 case of crankshaft phenomenon; 2 cases of flatback syndrome. CONCLUSION: Many kinds of complications may occur in scoliosis surgery. Exactitude procedures of diagnosis and surgery for the scoliosis are the key to decrease and prevent the complications related to the operation.