04/06/2026
Low back pain isn’t always from the disc. The sacroiliac (SI) joints can also be a major pain source, sometimes alone, sometimes alongside issues like L4-L5 or L5-S1 disc bulges.
Simple palpation helps differentiate: tenderness at L4-L5 points to disc involvement, while pain at the SI joints suggests they’re contributing too. This matters because treatment approaches are different for each.