Luminous visualisation of the fused triangular sacrum with the coccyx below it

Conditions by region

Pelvis & Tailbone (Sacral) Conditions

The sacrum and tailbone sit at the base of the spine, wedged between the pelvic bones. Problems here are routinely mistaken for ordinary lower back pain, but the pattern of pain — and what relieves it — tends to be different.

1 guide in this section.

SI Joint Pain as a Spine Mimic
Pain from the SI joint, where your pelvis meets the base of your spine, is commonly mistaken for a lumbar disc or nerve problem.

This article is general education, not medical advice. It cannot account for your history, imaging, or examination — talk to a qualified clinician about your own care.

Pelvis & Tailbone (Sacral) Conditions

Pelvis & Tailbone (Sacral) condition guides

SI Joint Pain as a Spine Mimic