Do Long-Term Thoracic Adaptations Occur in Pediatric Microtia Patients after Costal Cartilage Harvesting?

Abstract

Background: Among the various reconstructive options for congenital microtia, autologous rib cartilage grafting is widely used due to its favorable long-term aesthetic outcomes. However, concerns persist regarding postoperative chest wall deformities following costal cartilage harvest. This study assesses long-term morphological changes using 3-dimensional chest computed tomography scans, specifically focusing on patients who have reached full skeletal maturity.

Methods: A retrospective review was conducted on patients who underwent microtia reconstruction using rib cartilage graft. Only those who had follow-up computed tomography scans taken at least 5 years postoperatively and were older than 18 years at the time of the scan were included. Thoracic morphology at the costochondral junction midpoint (fifth to ninth ribs) was analyzed using key measurements, including transverse, anteroposterior, and sagittal dimensions, as well as modified Haller indices.

Results: A total of 21 male patients were included, with a mean follow-up period of 101 months. In the operative hemithorax, the costochondral junction midpoint shifted medially (fifth to ninth ribs), posteriorly (sixth rib), and exhibited less descent (sixth to ninth ribs) compared with the nonoperative hemithorax, with significant differences ( P < 0.05). In addition, the operative hemithorax had a smaller cross-sectional area than the nonoperative side (fifth to ninth ribs, P < 0.05). Although significant differences in the modified Haller Index were noted at the xiphisternal level, differences in thoracic height were minimal.

Conclusions: Despite perichondrium-preserving techniques, rib cartilage harvest leads to permanent thoracic asymmetry, particularly in transverse and sagittal dimensions. However, longitudinal compensatory growth appears to mitigate height differences after skeletal maturity. These potential deformities should be discussed with patients during preoperative counseling to ensure informed decision-making.