Does Harrington instrumentation improve pulmonary function in adolescents with idiopathic scoliosis? A meta-analysis.

A meta-analysis of the effects of Harrington instrumentation on vital capacity in adolescent patients with idiopathic scoliosis was conducted in an attempt to clarify the conflicting conclusions of different studies. Thirty-eight studies were assessed. Those that did not prevent sufficient statistical information and those that did not allow for normal growth during the interval between tests were excluded. The five studies remaining for analysis, involving a total of 173 patients, showed an increase in mean vital capacity ranging from 2% to 11% of predicted vital capacity. The weighted mean effect size for the five studies analyzed was 0.22 with 95% confidence intervals of 0.01-0.43. The authors conclude that Harrington instrumentation leads to a small but statistically significant improvement in vital capacity.