Comparison of single- and dual-rod techniques for posterior spinal instrumentation in the treatment of adolescent idiopathic scoliosis.

STUDY

DESIGN

Two groups of patients undergoing posterior spinal instrumentation and arthrodesis for treatment of adolescent idiopathic scoliosis were reviewed retrospectively.

OBJECTIVE

To compare intraoperative concerns (operative time and blood loss), complications, and outcome in patients undergoing single or double posterior rod instrumentation for treatment of adolescent idiopathic scoliosis.

SUMMARY OF BACKGROUND DATA: The current treatment of idiopathic scoliosis includes posterior spinal instrumentation and arthrodesis. The standard configuration is a rectangular construct of dual rods connected by cross-links. Use of a single rod with multiple fixation points has been proposed as an alternative method to decrease operative time and blood loss, and to avoid late deep infections.

METHODS

In this study, 21 patients underwent posterior instrumentation using a standard dual-rod construct, and 25 patients underwent posterior instrumentation using a solitary rod with multiple fixation points. Patients were assessed after a minimum 2-year follow-up period.

RESULTS

No significant differences were found in blood loss, operative time, or overall frequency of long-term complications. Although not statistically significant, the trend was toward implant prominence in the double-rod group and implant failure in the single-rod group. Implant failure occurred only in instrumentations extending into the lumbar spine. There was no statistical difference in curve progression.

CONCLUSIONS

Single-rod instrumentation and dual-rod constructs offered similar curve correction, blood loss, and operative time. However, single-rod instrumentation may be more prone to implant failure when extended into the lumbar spine.