A radiological study of the coccyx and sacral vertebra was carried out in 1,000 healthy individuals, and in 500 individuals suffering from coccygeal pain. In terms of the age distribution of individuals suffering from coccygodynia, the peak of the distribution curve was found at fourth decade. Morphologically, the incidence of dislocation type was as follows: In the normal group, it was 2.6% in males, and 5.2% in females; in the traumatic group, the dislocation type was 5.1% in males, and 8.1% in females, in the idiopathic group, it was 4.8% in males, and 11.1% in females. The sacro-coccygeal angle was greater in the female than in the male. From these results it may be concluded that there is a greater occurrence of idiopathic coccygeal regional pain among females, owing to certain motor disadvantages affecting body movement, as well as possible hormonal imbalance and morphological abnormalities.