What Can We Learn About Ribs and Vertebra Growth from an Osteological Collection

This is one of the first studies to use normative data from an osteological collection to make inferences about growth and development of the human ribs and thorax. Thirty-two pediatric spine and rib specimens from the Hamann-Todd Osteology Collection of the Cleveland Museum of Natural History were studied. There was symmetry and coupled growth between the upper and lower thoracic ribs. The mid-thoracic ribs appeared to grow linearly as rapidly as seen in the distal femur and increased in volume by the mathematical representation of a logarithmic spiral, similar to how other rigid biological structures grow in volume. The vertebral canal is relatively large in the cervical and lumbar spine compared to the thoracic spine, likely for neural protection, while accomodating for greater motion. Unlike other studies that have shown 95 % of the spinal canal area has been completed by age 5 years, our studies show that the canal is 95 % of adult area by age 10 years. However, the spinal canal continues to increase in cross-sectional area up to about age 15 years. Like the spinal canal area, the thoracic spine neurocentral synchondrosis remains partially open through age 17 years.