trephination

Trephination, or trepanation, is a surgical procedure that creates an opening in the skull. It is one of the oldest known medical operations; archaeological finds show its use in Neolithic skulls dating to about 7000 BCE in Europe, the Americas, and Africa. The procedure involves removing a circular section of bone or making a burr hole to expose the skull and underlying meninges. Historically, trephination has been performed for various reasons, including the relief of intracranial pressure after brain injury, treatment of seizures, headaches, or other conditions thought to be caused by supernatural forces. In many cases, skeletal remains show signs of postoperative healing, indicating that the patient survived for some period after the operation.

Techniques varied: early methods used stone, copper, or bronze instruments to cut or chip away bone, while later cultures employed more refined metal tools. A circular piece of bone might be removed, or a hole could be drilled and widened. In modern medicine, the analogous procedures are burr holes and craniotomies, performed with high-speed drills and specialized instruments under sterile conditions. The goal is to access the cranial cavity to treat injury, relieve pressure, evacuate hematomas, or place devices, while trying to minimize damage to the brain.

Trephination is now largely historical in many contexts, replaced by contemporary neurosurgical techniques. Nevertheless, it remains of interest in anthropology and history as evidence of early surgical skill and attempts to treat brain disorders. Complications include infection, hemorrhage, brain injury, and, in modern practice, irreversible neurological deficit, although when performed for appropriate indications with modern care, outcomes have improved significantly compared with historical rates.