Initial experience with 3D printing in the use of customized Nuss bars in pectus excavatum surgery

Pectus excavatum (PE) surgical repair according to Nuss procedure is based on the intrathoracic insertion of one (or more) metallic bars for anatomical defect repair. Number of bars, bar length, bar shape, and thoracic insertion site are established during surgery, according to patient morphology, CT-scan, and especially the surgeon's experience.

To assess the usefulness of the design, simulation, and 3D printing of customized Nuss bars for each patient.

A prospective descriptive study of all patients undergoing PE surgery under 3D printing from June to December 2019 was carried out. Curvature, bar length, and optimal intercostal space were designed based on diagnostic CT-scan, and they were 3D printed full size. The resulting model was reproduced preoperatively on the usual prosthetic material, sterilized, and kept until surgery.

The study cohort consisted of 6 patients. Median age was 15 years old (interquartile range: 14.25-15.25), median Haller index was 4.05 (interquartile range: 3.5-4.49), and repair index was 36.98% (interquartile range: 33.86-38.48%). A Nuss bar was introduced in all cases, without requiring removal or re-insertion. Median operating time was 79.5 minutes (interquartile range: 72.5-103). No postoperative complications were noted during follow-up (12 months).

The preoperative design of Nuss bars with customized shape and size facilitates surgical planning. It also allows for the most optimal and accurate morphological repair possible, according to patient anatomy, thus reducing the risk of requiring removal and/or re-insertion, and therefore, of surgical complications.