Surgical Treatment and Rediscussion of Day's Classification of Crescent Pelvic Fracture Combined with the Sacral Fracture.

Objective: The aim of this study was to summarize the surgical treatment of crescent pelvic fracture combined with the sacral fracture and rediscuss the Day’s classification in the pelvic crescent fractures. Methods: From May 2012 to May 2019, 24 patients of crescent pelvic fracture combined with the sacral fracture were included in this study (15 males, 9 females, mean age: 46.8 years). In this study, there were 8 cases, whose posterior bone mass was large, involving less than 1/2 of the sacroiliac joint. The lateral position was used and the arc incision along the posterior iliac ridge could be taken, the fracture should be first reduced and fixated with lag screw, and then with reconstruction plate. There were another 16 cases, whose posterior bone mass was small, involving more than 1/2 of the sacroiliac joint. For the patients with less injury of sacroiliac joint posterior ligament, the anterior ring of pelvis was fixated first, then the arc-shaped incision along the posterior iliac ridge on both sides was taken in prone position, the fracture could be reduced and fixated with lag screws and then fixated with tension plate. For the patients with server sacroiliac joint complex injury, the open reduction of anterior and posterior rings of the pelvis was taken in the floating position and fixation or arthrodesis of the sacroiliac joint could be taken. For the patients without obvious displacement of the sacroiliac joint, the anterior and posterior approaches could be used at the same time in the supine position to fixate the sacroiliac joint fixation. In addition, the average operation time, the mean blood loss, displacement differences between preoperation and postoperation, fracture union time and Hannover Scoring System were recorded. Results: The average operation time was 75 mins (range from 40 mins to 160 mins), the mean blood loss was 561.7 ml (range from 300 ml to 1100 ml). Meanwhile, no lumbosacral radiculomyelitis was injured in these cases. The mean follow-up period was 16.1 months (range from 12 months to 36 months) and the mean radiographic healing time was 3.6 months (range from 3 months to 6 months) respectively. Due to Hannover Scoring System, 18 patients were in excellent condition and 6 patients were in good condition. Conclusion: The crescent pelvic fracture combined with the sacral fracture was not included in current Day’s classification. We treated 24 cases of crescent pelvic fracture combined with the sacral fracture and obtained good clinical outcome. Therefore, we posed a new type to complement it to the Day’s classification, which was defined as crescent pelvic fracture combined with sacral fracture. It was helpful for the surgeons to choose suitable approach and implants.