Trepanation
From Wikipedia, the free encyclopedia
18th century French illustration of trepanationTrepanation (also known as trepanning, trephination, trephining or burr hole) is a form of surgery in which a hole is drilled or scraped into the skull, thus exposing the dura mater in order to treat health problems related to intracranial diseases, though in the modern era it is used only to treat epidural and subdural hematomas, as an extreme body modification, and for surgical access for certain other neurosurgical procedures (e.g. intracranial pressure monitoring).
A trepan may also refer to a rock-boring tool used for sinking mine shafts. It is also a kind of industrial drill bit, commonly used to bore large diameter holes in metal and sometimes referred to as a BTA drill. The drill characteristically leaves a core.
Trepanation is also a technique used by Bomb Disposal units where a bore is cut into the sidewall of a bomb and the explosive contents are extracted through a combination of steam and acid bath liquification of bomb contents. UXO trepanation procedures were used mainly after WWII and were developed by the British UXO units.
Trepanation was carried out for both medical reasons and mystical practices for a long time: Evidence of trepanation has been found in prehistoric human remains from Neolithic times onwards, per cave paintings indicating that people believed the practice would cure epileptic seizures, migraines, and mental disorders.[Brothwell, D.R. Digging up Bones. 1963:126] Furthermore, Hippocrates gave specific directions on the procedure from its evolution through the Greek age.
Trepanation in the Old World
Trepanation is perhaps the oldest surgical procedure for which there is evidence[1], and in some areas may have been quite widespread. Out of 120 prehistoric skulls found at one burial site in France dated to 6500 BC, 40 had trepanation holes.[2] Surprisingly, many prehistoric and premodern patients had signs of their skull structure healing; suggesting that many of those that proceeded with the surgery survived their operation.
Trepanation was also practiced in the classical and Renaissance periods. Hippocrates gave specific directions on the procedure from its evolution through the Greek age, and Galen elaborates on the procedure, too. Doctors in ancient Egypt used the scrapings of the skull to create love potions and other concoctions.[citation needed]
During the Middle Ages and the Renaissance, trepanation was practiced as a cure for various ailments, including seizures and skull fractures. The surgeons who performed these trepanations were probably highly skilled because the survival rate of the operations was high and the infection rate was low.[3]
Trepanation in pre-Columbian Mesoamerica
Trepanation in Mesoamerica
In pre-Columbian Mesoamerica, evidence for the practice of trepanation and an assortment of other cranial deformation techniques comes from a variety of sources, including physical cranial remains of pre-Columbian burials, allusions in iconographic artworks and reports from the post-colonial period.
Among New World societies, trephinning is most commonly found in the Andean civilizations such as the Inca.[4] Its prevalence among Mesoamerican civilizations is much lower, at least judging from the comparatively few trepanated crania which have been uncovered.[5]
The archaeological record in Mesoamerica is further complicated by the practice of skull mutilation and modification which was carried out after the death of the subject, in order to fashion "trophy skulls" and the like of captives and enemies. This was a reasonably widespread tradition, illustrated in pre-Columbian art which on occasion depicts rulers adorned with or carrying the modified skulls of their defeated enemies, or of the ritualistic display of sacrificial victims. Several Mesoamerican cultures used a skull-rack (known by its Nahuatl term, tzompantli ) on which skulls were impaled in rows or columns of wooden stakes.
Even so, some evidence of genuine trepanation in Mesoamerica (i.e., where the subject was living) has been recovered.
The earliest archaeological survey[6] published of trepanated crania was a late 19th-century study of several specimens recovered from the Tarahumara mountains by the Norwegian ethnographer Carl Lumholtz.[7] Later studies documented cases identified from a range of sites in Oaxaca and central Mexico, such as Tilantongo, Oaxaca and the major Zapotec site of Monte Alb�n. Two specimens from the Tlatilco civilization's homelands (which flourished around 1400 BCE) indicate the practice has a lengthy tradition.[8]
A study of ten low-status burials from the Late Classic period at Monte Alb�n concluded that the trepanation had been applied non-therapeutically, and, since multiple techniques had been used and since some people had received more than one trepanation, concluded it had been done experimentally. Inferring the events to represent experiments on people until they died, the study interpreted that use of trepanation as an indicator of the stressful sociopolitical climate that not long thereafter resulted in the abandonment of Monte Alban as the primary regional administrative center in the Oaxacan highlands.[citation needed]
Specimens identified from the Maya civilization region of southern Mexico, Guatemala and the Yucat�n peninsula show no evidence of the drilling or cutting techniques found in central and highland Mexico. Instead, the pre-Columbian Maya seemed to have utilised an abrasive technique which ground away at the back of the skull, thinning the bone and sometimes perforating it, similar to the examples from Cholula. Many of the skulls from the Maya region date from the Postclassic period (ca. 950�1400), and include specimens found at Palenque in Chiapas, and recovered from the Sacred Cenote at the prominent Postclassic site of Chichen Itza in northern Yucat�n.[9]
