Bone scan/single-photon emission computed tomography findings in pectus excavatum following the nuss operation

The Nuss operation is popular worldwide as a minimally invasive surgery for alleviating pectus excavatum. However, information regarding the stress and strain on the deformed ribs after the operation is lacking. A bone scan is a superior imaging method to detect rib fractures. In this study we examined the findings of 99mTc-diphosphonate bone scan and single-photon emission computed tomography (SPECT) in pectus excavatum patients with a history of the Nuss operation. The bone scan and SPECT images of patients with a history of the Nuss operation for pectus excavatum from March 2012 to January 2013 were retrospectively reviewed. Bone scans and SPECT images of 20 patients (3 females, 17 males; mean age 15±9 years) were examined at baseline and after the Nuss operation. The mean time interval between the Nuss operation and postoperative bone scan and SPECT was 26±13 days. Baseline bone scan and SPECT images showed caved-in appearance in the anterior chest wall, but no definite abnormal activity. After the Nuss operation, multifocal and/or diffuse increased activities were observed at the costochondral junctions and anterior/anteroaxillary areas of both rib cages and sternum. The bone scan/SPECT images in patients following the Nuss operation for pectus excavatum demonstrated abnormally increased bone uptake in the rib cage and/or sternum. This abnormal bone uptake was possibly due to minute fractures caused by constant/repetitive stress and direct injury by a metal bar to the bony thorax after the Nuss operation.