Does postoperative shoulder imbalance affect patient reported functional outcomes after posterior surgical correction of adolescent idiopathic scoliosis? A systematic review and meta-analysis.

Purpose: Failure to balance the shoulders whilst surgically correcting AIS has been reported in many publications as being associated with negative PROMS. However, the evidence to support this, in our opinion, is limited. The purpose of this study was to systematically review the literature and perform a meta-analysis to identify whether postoperative shoulder imbalance affects patient reported outcome measures.

Methods: A systematic review and meta-analysis was conducted on the available literature comparing clinical and/or radiographic features of postoperative shoulder imbalance following surgery for AIS with patient reported outcome measures.

Results: Thirteen studies with 924 patients were included. The mean follow-up was 3.7 years (2-16). The incidence of radiographic PSI was 30.1% and clinical PSI was 22.7%. A mix of validated (most commonly used SRS-22) and nonvalidated PROMs were used. Studies using radiographic PSI assessment showed no difference in PROMs for most validated scores. Clinical assessment studies showed that patients with even shoulders were also unsatisfied with their appearance. Meta-analysis of the extractable and analysable data showed no significant difference in PSI vs No-PSI in SRS-22.

Conclusion: Contrary to popular belief, the findings of this systematic review and meta-analysis demonstrate that PSI is not associated with negative PROM using validated outcome measures.