Rib overgrowth may be a contributing factor for pectus excavatum: Evaluation of prepubertal patients younger than 10years old.

BACKGROUND/PURPOSE: We compared the costal cartilage and rib length between prepubertal patients with symmetric pectus excavatum and age- and sex-matched controls without anterior chest wall depression to evaluate if rib overgrowth is a contributing factor for pectus excavatum

METHODS

The sample included 18 prepubertal patients <10years old with symmetric pectus excavatum and 18 age-and sex-matched controls without chest wall deformity. The full lengths of the fourth to sixth ribs and costal cartilage were measured using three-dimensional volume-rendered computed tomography and curved multiplanar reformatting techniques. The rib and costal cartilage lengths, total combined rib and costal cartilage length, and costal index ([length of cartilage/length of rib]×100 [%]) at the fourth to sixth levels were compared between the groups.

RESULTS

The rib lengths in the patient group were significantly longer than in the control group for the 6th right rib and 4th, 5th, and 6th left ribs. The costal cartilage lengths and costal indices were not different between two groups.

CONCLUSIONS

In patients with symmetric pectus excavatum aged <10years old, several of the ribs were longer than those of controls, suggesting that abnormal rib overgrowth may be a contributing factor responsible for pectus excavatum rather than cartilage overgrowth.