Scoliosis and Pectus Excavatum in Adolescents: Does the Nuss Procedure Affect the Scoliotic Curvature?

Background: Pectus excavatum (PE) is known to be associated with adolescent idiopathic scoliosis (AIS). The correction of severe PE requires a mini-invasive procedure (MIRPE), with a metal bar positioned and left in the chest for 3 years. Adolescence seems to be the more appropriate time not only for MIRPE but also for AIS peak progression. This study was designed to answer the question whether, in adolescents, MIRPE could affect mild/moderate AIS. Methods: We carried out a meta-analysis focused on defining the natural progression of untreated AIS. Inclusion criteria were as follows: AIS patients -age 10-18 years old -Cobb angle <40°-none treated as orthotics/electrostimulation/surgery. The expected outcome was the percentage of patients who improved, worsened, or hold steady of their condition at follow-up. Between 2008 and 2014, we followed up a cohort of 67 adolescents with severe PE treated with MIRPE, assessing whether AIS underwent a modification in the period between bar insertion and removal. Results: Meta-analysis included 9 studies with 1641 AIS patients. Although heterogeneous (I2 = 99.5%, P < .0001), the overall percentage of progression for untreated AIS was 42.5% (CI 18.2%-72.2%). In our follow-up group who underwent MIRPE, 34 out of 67 patients had concurrent AIS with a Cobb angle >10° (range 10°-45°). We demonstrated that MIRPE had a favorable effect on AIS, with a mean improvement of 1.5° (CI 0.64-2.44; P = .0011). Conclusion: In our PE patients with AIS, MIRPE had a beneficial effect also on the spine. From our preliminary results, it seems that MIRPE should be offered during puberty as a timely option for treating PE and stabilizing mild/moderate scoliosis progression, when concurrent.