compoundfractur:

Trephination, or trepanning, is the oldest surgical procedure in the history of humankind. It’s so old that our earliest archeological evidence of the practice dates back to the Neolithic age. Cave paintings depict the procedure as an effort to relieve a type of demonic possession that we would now label epilepsy or a variety of other mental maladies. It was also used to removed broken bits of skull after trauma, and drain blood pooling between the skull and dura matter. The crazy thing about the prehistoric use of puncturing-a-hole-in-your-freaking-skull was that most of the wounds show signs of healing, indicating that these people most often survived the procedure. Other archeological evidence suggests that these people would wear the fragment of skull removed as a charm.

We still trephinate people today, typically to relieve the effects of severe head trauma and for craniectomy (unfortunately if you have this done today they won’t give you the bone to wear as a charm. I figure if I’m letting them crack open my skull the least they could do is give me a souvenir).

Heartbeat in the Brain

Surgeon Conducting a Trephination, from Anothomia Designata per Figures (1345) - Guido da Vigevano (also known as Guido da Pavia)