Sacroiliac screw versus a minimally invasive adjustable plate for Zone II sacral fractures: a retrospective study

Fracture line of the sacrum always involves the Zone II region because sacral foramina are anatomically and physiologically weak regions of the sacrum. The purpose of this study is to compare the therapeutic effects of a sacroiliac screw and a minimally invasive adjustable plate (MIAP) for Zone II sacral fractures.

Patients with unilateral Zone II sacral fractures fixed with a unilateral sacroiliac screw or MIAP from August 2009 to January 2016 were recruited into this study and were divided into two groups: group A (sacroiliac screw) and group B (MIAP). Surgical time, blood loss, frequency of intraoperative fluoroscopy, and relative complications were reviewed. Radiographs and CT scans were routinely acquired to evaluate the fracture displacement and reduction quality. Fracture healing was evaluated in the radiographs at each follow-up. Functional outcome was assessed based upon the Majeed scoring system at the final follow-up.

Thirty-one patients in group A and thirty-nine patients in group B were included in this study. No significant differences in average surgical time (P = 0.221) or blood loss (P = 0.234) were noted between group A and group B. The mean frequency of intraoperative fluoroscopy was 15.74±2.98 in group A and 6.08±1.94 in group B (P = 0.000). All fractures healed well within four months in all patients, and the healing time exhibited no significant difference between the two groups (P = 0.579). Satisfactory rates of reduction quality and functional outcome were not statistically different between the two groups (P > 0.05). The complication rate was 16.13% (5/31) in group A and 5.13% (2/39) in group B (P = 0.222).

MIAP has a fixation effect and exhibits reduction potential for Zone II sacral fractures. Favourable radiographic and functional results could be obtained through the MIAP technique, which is easy to conduct without pre-contouring. Compared with the unilateral S1 sacroiliac screw technique, repeated projections and iatrogenic sacral injury can be avoided.