Use of a customised 3D-printed external splint for the correction of a severe pectus excavatum in a 3-month-old kitten

Background: Pectus excavatum is a rare congenital or developmental deformity of the chest wall that has been reported in both dogs and cats. The clinical symptoms vary in severity and are correlated with the grade of the deformity. The most severe cases are at a very high risk of intra- and post-operative complications that could be fatal. Case Description: A 3-month-old kitten was presented for severe dyspnea and exercise intolerance. After the radiographic diagnosis of severe pectus excavatum, a splint was designed based on the computed tomography scan of the kitten. A locking mechanism was applied on a dedicated pocket on the splint and secured with commercial glue. Five sutures were placed, the most caudal three with a surgical approach to the corresponding sternebra. The three caudal traction sutures were progressively tensioned during the first 2 weeks, and then tied. The splint was removed 1 month postoperatively; neither surgical nor splint-associated complications were observed. The kitten well tolerated the splint and the owner reported no further episodes of dyspnea or exercise intolerance. Vertebral and frontosagittal indexes were 3.2 and 9.1 at presentation, respectively, and 10.2 and 2.0 at 4 months postoperatively. Conclusion: The use of a patient-specific 3D-printed external splint associated with a progressive correction of the pectus excavatum can be a better solution for the treatment of severe cases of pectus excavatum, where a sudden distension of the rib cage could cause re-expansion injuries