Abstract:

BACKGROUND: Sacroiliac screw has been widely used in the treatment of the sacroiliac joint dislocation, but it cannot achieve strong mechanical intensity due to its poor biomechanical properties.
OBJECTIVE: To explore the mechanical intensity and clinical efficacy of posterior nail-rod for the treatment of sacroiliac joint dislocation.
METHODS: ①Twelve cadaveric pelvis specimens, six males and six females, were selected to make the sacroiliac joint dislocation model and pubic symphysis separation model by cutting off the sacroiliac joint ligaments and pubic symphysis structure. Specimens were randomly divided into two groups: iliosacral screw fixation group and pelvis posterior single nail-rod fixation group, specimens in the two groups were fixed with iliosacral screw and pelvis posterior single nail-rod respectively. ②The clinical indications of ingle nail-rod system were set up, and the clinical data of 16 sacroiliac joint dislocation patients were collected, Mears image evaluation standard and pelvic fractures Majeed curative effect were used to assess data statistics and score.
RESULTS AND CONCLUSION: In the same load, the displacement, axial stiffness, ultimate-load and yield-load of the posterior single nail-rod group were larger than those of iliosacral screw group (P < 0.05). All the 16 patients were followed-up for an average of 23.2 months (3-45 months). According to Mears image standard, there were 13 cases of anatomical replacement, and 3 cases in satisfaction. Pelvic fractures Majeed score was 60 to 100 points, 82 points in average; the good rate of C1 type fracture was 82%, and good rate of C2 type fracture was 80%. Compared with iliosacral screw fixation, the single nail-rod fixation for the treatment of sacroiliac joint dislocation has reliable strength stiffness and clinical curative effect.