The Surgical Treatment Of Sacral Fracture (Denis Ⅱ Fracture) With Sacral Neurological Damage And Applied Anatomy Of Presacral Foramen Region

Objective: To explore the surgical treament of scaral fracture (Denis II ) and provide anatomical data for posterior approach enlargement for sacral nerve canal. Methods:Posterior approach enlargement for sacral nerve canal--a newsurgical procedure to Denis II sacral fracture was used in 11 cases. The blood vessels, sacral nerve of presacral region and piriformis were observed and measured on 26 adult cadaveric specimens. Results: (1) 11 patients were followed up from 3 to 42 months with an average of 16 months. According to the BMRC score system the excellent result was obtained in 9 cases, good in 1 case, no change in 1 case. (2) Lateral sacral artery usually has two branches and its branches enter the anterior sacral foramen. (3) The point of superior gluteal artery go through sacral plexus is 29. 99 7. 25mm lateral to the AB line, -11.33 9.86 inferior to the S,. (4) Lateral sacral vein anastomoses with superior gluteal vein. The presacral veniplex has wide souse and is full of anastomosis. (5) The angle of S1, S2, S3, S4 lateral to AB line is 63. 13 11. 65 , 71.24 11. 78 , 70.24 11.26 , 79. 69 16. 17 respectively. (6) The superior edge of piriformis is -11.46 11.02mm, 12. 65 10.00mm to S1, S2 on AB line. The distance between the point that S1 nerve crossing the superior edge of piriformis and S1 is 22. 85 9. 81mm. Conclusions: The new surgical approach may be a ideal approach to treat sacral neurological damage of scaral fracture (Denis II). The operation preferably go flowing the angle of sacral nerve and can stop when meet the piriformis.