(translated by Spink MS, Lewis GL). Berkeley, CA: University of California Press, 1973 pp 735–777.
Albucasis - Abu al-Qasim Khalaf ibn Abbas al-Zahrawi (936–1013)
If the last bone of the coccyx, which is the sacrum of the tail, breaks, introduce the thumb of your left hand into his anus and reset the bone with the other hand in whatever way is possible and affords the best setting; then apply over it a plaster, and a splint if necessary, and bind it up. And if you perceive a fragment in the fracture, cut down upon it, remove it, and dress the wound as before said, until it heals.
This account of treatment is very similar to that of Paulus Aegineta, though it goes into more detail about manual treatments than Paulus does. The translator of Paulus says (when discussing treatment of fracture of the scapula) "Albucasis and Avicenna, as usual, copy from our author."