Sacral orientation and Scheuermann's kyphosis

Area of Science:

• Orthopedics and skeletal biology.
• Biomechanical analysis of spinal deformities.

Background:

• Scheuermann's kyphosis is a spinal deformity characterized by excessive outward curvature.
• The role of sacral anatomical orientation (SAO) in the development of spinal deformities is not fully understood.

Purpose of the Study:

• To investigate the relationship between spinal alignment and sacral anatomical orientation (SAO) in skeletal populations.
• To compare SAO values in individuals with Scheuermann's kyphosis to those with normal spinal alignment.

Main Methods:

• Screened 2025 skeletons for Scheuermann's disease based on specific vertebral wedging criteria.
• Measured SAO using a defined angle on 185 individuals with normal spines and 183 with Scheuermann's kyphosis.
• Analyzed SAO differences between the two groups.

Main Results:

• Identified 183 cases (9%) of Scheuermann's kyphosis among the screened skeletons.
• Found that the sacrum was significantly more horizontally oriented in individuals with Scheuermann's kyphosis (SAO: 44.44° ± 9.7°) compared to controls (SAO: 50° ± 9.9°).
• The difference in SAO between groups was statistically significant (p < 0.001).

Conclusions:

• A horizontally oriented sacrum is associated with Scheuermann's kyphosis.
• Altered spinal biomechanics resulting from a more horizontal sacrum may contribute to the development of Scheuermann's kyphosis.