Role of triangular osteosynthesis in vertically unstable transforaminal sacrum fractures: clinical and radiological outcomes.

PURPOSE: We aim to report clinical and radiological results of triangular osteosynthesis for a homogenous group of vertically unstable transforaminal sacral fractures.

METHODS

Between 2013 and 2018, 22 consecutive patients with unstable sacral fractures were treated with triangular osteosynthesis consisting of iliosacral screw augmented by spinopelvic fixation. Patients were followed up prospectively as a single cohort. Bone union, complications, clinical and radiological outcomes were investigated.

RESULTS

Mean follow-up was 3.1 years (12-76 months). There was one bilateral fracture. Two patients underwent anterior plating for pubic symphyseal disruption. Based on Majeed and Iowa pelvic scores, 13 patients had excellent, seven had good and two had fair clinical outcome. All the patients could perform squatting, sitting cross-legged and kneeling without any restrictions. There were no additional neurological injuries. One patient had non-union of sacral fracture, one patient had deep infection, one patient had marginal wound necrosis and two patients complained of pain related to implant prominence. Two patients had connecting rod backout. All but one patient attained pre-operative work status.

CONCLUSION

Triangular osteosynthesis is a reliable procedure in treating unstable transforaminal sacral fractures. It permits early weight-bearing and facilitates faster functional recovery. Careful attention to details such as sacral dysmorphism, soft tissue injury, implant placement and anterior pelvic injury helps in keeping complications to an acceptable rate.