Trepanation (also known as trepanning , trephination , trephining or making a burr hole ) is a medical intervention in which a hole is drilled or scraped into the human skull, exposing the dura mater in order to treat health problems related to intracranial diseases. It may also refer to any "burr" hole created through other body surfaces, including nail beds. It is often used to relieve pressure beneath a surface. A trephine is an instrument used for cutting out a round piece of skull bone.
Evidence of trepanation has been found in prehistoric human remains from Neolithic times onwards. Cave paintings indicate that people believed the practice would cure epileptic seizures, migraines, and mental disorders. The bone that was trepanned was kept by the prehistoric people and probably worn as a charm to keep evil spirits away. Evidence also suggests that trepanation was primitive emergency surgery after head wounds to remove shattered bits of bone from a fractured skull and clean out the blood that often pools under the skull after a blow to the head. Such injuries were typical for primitive weaponry such as slings and war clubs.
There is some contemporary use of the term. In modern eye surgery a trephine instrument is used in corneal transplant surgery. The procedure of drilling a hole through a fingernail or toenail is also known as trephination. It is performed by a physician or surgeon to relieve the pain associated with a sub-ungual hematoma (blood under the nail); a small amount of blood is expressed through the hole and the pain associated with the pressure is partially alleviated.
History
Main article: History of medicineOld World
See also: Prehistoric medicineTrepanation is perhaps the oldest surgical procedure for which there is forensic evidence, 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. Many prehistoric and premodern patients had signs of their skull structure healing; suggesting that many of those subjected to the surgery survived.
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 also elaborates on the procedure.
During the Middle Ages and the Renaissance, trepanation was practiced as a cure for various ailments, including seizures and skull fractures. Out of eight skulls with trepanations from the 6th-8th centuries found in southwestern Germany, seven skulls show clear evidence of healing and survival after trepanation suggesting that the survival rate of the operations was high and the infection rate was low.
Pre-Columbian Mesoamerica
Main article: Trepanation in MesoamericaIn 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, trepanning is most commonly found in the Andean civilizations such as the pre-Incan culture such as the Paracas Ica situated in what now is Ica located South of Lima. Its prevalence among Mesoamerican civilizations is much lower, at least judging from the comparatively few trepanated crania that have been uncovered.
The archaeological record in Mesoamerica is further complicated by the practice of skull mutilation and modification carried out after the death of the subject, to fashion "trophy skulls" and the like of captives and enemies. This was a widespread tradition, illustrated in pre-Columbian art that occasionally 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 survived.
The earliest archaeological survey published of trepanated crania was a late 19th-century study of several specimens recovered from the Tarahumara mountains by the Norwegian ethnographer Carl Lumholtz. 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 Albán. Two specimens from the Tlatilco civilization's homelands (which flourished around 1400 BC) indicate the practice has a lengthy tradition.
A study of ten low-status burials from the Late Classic period at Monte Albán 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.
Specimens identified from the Maya civilization region of southern Mexico, Guatemala and the Yucatán Peninsula show no evidence of the drilling or cutting techniques found in central and highland Mexico. Instead, the pre-Columbian Maya apparently used an abrasive technique that ground away at the back of the skull, thinning the bone and sometimes perforating it, similar to the examples from Cholula. Many 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 Yucatán.
Modern medicine
Trepanation is a treatment used for epidural and subdural hematomas, and for surgical access for certain other neurosurgical procedures, such as intracranial pressure monitoring. Modern surgeons generally use the term craniotomy for this procedure. The removed piece of skull is typically replaced as soon as possible. If the bone is not replaced, then the procedure is considered a craniectomy. Trepanation instruments are now available with diamond coated rims (Diamond Bone Cutting System), which are less traumatic than the classical trephines with sharp teeth. They are smooth to soft tissues and cut only bone.
Voluntary trepanation
Although widely considered today to be pseudoscience, the practice of trepanation for other purported medical benefits continues. Moreover recent research on the increase in cranial compliance following on trepanation, with resulting increase in blood flow, seems to vindicate some of the claims widely considered mere pseudoscience.
The most prominent folk theory for these benefits is offered by Dutchman Bart Huges (alternatively spelled Bart Hughes). He is sometimes called Dr. Bart Hughes although he did not complete his medical degree. Hughes claims that trepanation increases "brain blood volume" and thereby enhances cerebral metabolism in a manner similar to cerebral vasodilators such as ginkgo biloba. No published results have supported these claims.
Other modern practitioners of trepanation claim that it holds other medical benefits, such as a treatment for depression or other psychological ailments. In 2000, two men from Cedar City, Utah were prosecuted for practicing medicine without a license after they performed a trepanation on an English woman to treat her chronic fatigue syndrome and depression.
However, individuals may practice non-emergency trepanation for psychic purposes. A prominent proponent of the modern view is Peter Halvorson, who drilled a hole in the front of his own skull to increase "brain blood volume".
In a chapter of his book, Eccentric Lives & Peculiar Notions , John Michell describes a British group that advocates self-trepanation to allow the brain access to more space and oxygen. The chapter is called "The People With Holes in their Heads". Michell cites Bart Huges as pioneered the idea of trepanation specifically his 1962 monograph, Homo Sapiens Correctus , as most cited by advocates of self-trepanation. Among other arguments, he contends that children have a higher state of consciousness and since children's skulls are not fully closed one can return to an earlier, childlike state of consciousness by self-trepanation. Further, by allowing the brain to f
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