What are the fused articular processes of the sacrum called?

• A. Median Sacral Crest
• B. Lateral Sacral Crest
• C. Intermediate Sacral Crest
• D. Sacral Tuberosity

Answer: (C)

The dorsal crests on the sacrum come from the fused parts of the original vertebrae. The intermediate sacral crest specifically is formed by the fusion of the articular processes of the sacral segments. That makes it the ridge you feel running along the back between the sacral foramina, reflecting where the articular joints between the segments once stood. This is distinct from the median sacral crest, which is the fusion of the spinous processes, and the lateral sacral crest, which is the fusion of the transverse processes. The sacral tuberosity is a separate rough area where ligaments attach, not formed by fused articular processes.