'Snapping hip' and sacroiliac sprain: example of a cause-effect relationship.

A case history demonstrating a cause-effect relationship between sacroiliac sprain and a 'snapping hip' is presented. Periodic iliac manipulation is shown to eliminate crepitus elicited by simultaneous active or passive extension of the knee and hip. The significance of this case history as evidence of the efficacy of iliac manipulation in the management of sacroiliac syndrome is discussed.