TO PERFORM THE FORTIN FINGER TEST
place your finger directly on the area of your pain
with ONE FINGER two times.
According to the results of this study,
if you point to the exact spot where the sacroiliac
joint is located (right or left) each time, your pain
is likely coming from the SI joint. See diagram below
for location of sacroiliac joints.
The SI joints are located immediately
below and to the inside of the posterior superior iliac
spines, which feel like small boney bumps on each side
of your lower back. Either side can be painful.
JD, Falco FJ. The Fortin finger test: an indicator of
sacroiliac pain. Am J Orthop. 1997 Jul;26(7):477-80.