Sacro-Iliac Joint Sensory Block and Radiofrequency Ablation: Assessment of Bony Landmarks Relevant for Image-Guided Procedures

Figure 4

Variation in the shape and size of the posterior sacral foramina. (a) and (b) photographs of male sacra; (c) and (d) photographs of female sacra.

(a)

(b)

(c)

(d)