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Need it like I need a Hole in the Head: A History of the World’s Earliest Neurosurgery

By J. LaValley

Often, when we discuss medical practices of the past, we do so with a certain level of scorn, horror, and disgust. These aren’t unreasonable reactions when thinking of things like bloodletting, strange animal parts and bodily fluids used as poultices (a substance applied to a wound to promote healing), or ingesting mercury to cure any number of ailments. Although some of these concepts appear like quackery best left in the past, others are quite logical, and potentially successful, treatments. One such procedure that gets a bad rep is trepanation. Trepanation, also termed trephination, is defined as ‘the act of drilling, cutting, or scraping a hole in the skull for medical reasons’ (Wade, 2018). This is an old practice that dates back as early as the Neolithic Age (10,000-4,500 BCE) and evidence for it has been found, to some degree, on every populated continent (Ghannaee Arani et al., 2001; Hobert & Binello, 2017; Webb, 1988; Wade, 2018).

Figure 1: Illustration of a skull with different trepanation methods being demonstrated. Numbers indicate: 1) scraping, 2) chiseling a circle, 3) joining of various burr holes, and 4) linear grooves forming a square. (Source: Tullo, 2010 via Charles C Thomas)

Why on earth would you drill a hole in your skull?

Before you recoil in horror, keep in mind that trepanation is actually still performed, in some fashion, in modern medicine. Today, we generally refer to it as either a craniotomy (temporary removal of a section of skull in order to access the brain) or burr holes (small holes drilled into the skull). Craniotomies are generally used to access the brain for a surgical procedure while burr holes are used to feed in tubing to reduce a subdural hematoma, a dangerous build up of blood between the brain and the brain’s lining (Shim et al., 2019). These hematomas can arise for a number of reasons, including head trauma, disease complications, or even chronic conditions such as coagulopathy (a bleeding disorder in which the blood’s ability to form clots is impaired). Without intervention, these will often cause either severe brain trauma or death (Wilberger et al., 1991).

How do we know ancient people were performing this procedure?

The ‘discovery’ of ancient peoples performing this type of procedure came to the attention of western medicine in the late 1800’s and was met with a good amount of scorn. This scorn stemmed mainly from racist ideas of the time period (Gross, 2021). Though the first trepanned skulls were found in Inca burial grounds, few people believed that such ‘primitive’ people could perform this complex surgery – a surgery that in the late 1800’s only had a 10% success rate in hospitals (Gross, 2021). Interestingly, it wasn’t until a Neolithic gravesite was uncovered in France that scientists began believing that ancient peoples were capable of performing this procedure (Gross, 2021). What shocked researchers so much about the Inca was the number of skulls that were found to possess evidence of healing. This indicated that a large percentage of people were surviving this procedure– something that was not the case in their current time. 

The earliest skulls were found in modern day Peru and are dated from 400 BCE-200 BCE, and markers for post-surgical healing put survival rates somewhere around 40% (Kushner et al., 2018). For comparison, in Civil War America, there was a 50-60% survival rate. When you track the skulls in the regions the Inca occupied over time, you see a refinement in technique: the holes get smaller, the extraneous damage is lessened, and the survival rate increases to 91% by 1000 CE (Kushner et al., 2018).

Figure 2: A skull found in Jericho, Palestine, displaying three trepanation holes with visible healing markers, indicating the patient survived the procedure(s). (Source: Wellcome collection via Wellcome Images)

But why such stark differences in survival?

While the Incas’ skill is truly something to be applauded, it should be acknowledged that some of the differences in survival rates were due to the conditions and situations the procedure was performed in. As mentioned, in 19th century hospitals, there was about a 10% success rate for trepanations. However, hospitals at the time were some of the last places you wanted to be if you were ill or injured. Even for lower-limb amputations before the acceptance of germ theory (the idea that microscopic organisms cause specific diseases), survival could range between 75% to an abysmal 50% depending on the hospital (Chaloner et al., 2001; Reilly, 2016). Trepanation in hospitals was also only performed in the most severe situations, such as when people were unlikely to survive without the surgery. This was because in this time period, the practice had gone out of favor and was seen as too high a risk of infection and death. Ironically, the practice of performing surgeries in a hospital setting rather than in a patient’s home seems to have led to an increase in mortality that caused procedures like trepanation to be so high-risk (Gross, 2021). For battlefield care, like in the Civil War, trepanation was still being performed in extremely unclean environments. However, it was a much more common procedure and was utilized in less severe patients, thus explaining the rise in survival to 50-60% (Wade, 2018). The Inca, on the other hand, were performing these procedures in the open air and, at least sometimes, with single-use tools (Chaves-Rivera & Sanchez, 2022). This was significantly cleaner than the protocols in the 1800’s, where you were lucky if your surgeon rinsed his hands between procedures. Even with all of these caveats, it is important to acknowledge what an achievement it was to develop prowess in such a delicate medical procedure. Additionally, it is important to remember that the Inca made a specific and conscious choice to perform surgeries in the open air and with single-use tools. We should not assume these circumstances to be happenstance.

… the practice of performing surgeries in a hospital setting rather than in a patient’s home seems to have led to an increase in mortality that caused procedures like trepanation to be so high-risk

Why were ancient people performing these procedures?

While the scientific community of the 1800’s ultimately accepted that historical people were in fact successfully performing these surgeries, they still questioned why they were being performed at all. A notion was introduced, and can still be found today, that it was a religious or spiritual practice. This is a theme often observed throughout history; if the purpose of an object, archeological site, or practice is unknown, or we don’t believe the people of the time could possibly use it the way we would today, then it is fettered with the label “for ritual purposes” (Bower, 2018). However, researchers are moving away from this idea (Arnott, 2003). Based on examinations of extant skulls and historical texts on the subject, the general consensus has become that trepanation was used to either treat head injuries or illnesses (Arnott, 2003; Gross, 2021). Looking at texts written by Hippocrates and Galen from ancient Greece and Rome, we find detailed instructions and medical indications for performing trepanation. They most commonly recommended this procedure for head trauma, including what we now call subdural hematomas. Galen, building off of the work done by Hippocrates, was also able to recognize that the biggest risk of head trauma was due to the pressure it could cause in the brain rather than the damage to the skull itself, which he noted resulted in symptoms like nausea and altered mental states (Missios, 2007).

This is not to say that there is no situation in which trepanation could have been used as a spiritual or religious practice, or at least influenced by religious beliefs of the time. From 150 CE to 17th century Europe, trepanation was also reportedly employed for treatment of epilepsy (Gross, 2021; Asadi-Pooya & Rostami, 2017). This treatment was meant to ‘release the spirits’ trapped in the skull that were causing the condition. For a couple hundred years since the 17th century, trepanation was also used to treat madness thought to be caused by similar spirits plaguing the mentally ill (Gross, 2021). Early reports of trepanation from regions in Kenya also remark that it was done to ‘prevent them being plagued in their afterlives by a flow of rheum from the head’ (Gross, 2021). However, it should be noted that modern members and descendants of the tribe referenced in this quote dismiss this notion and state it is done for medical purposes, such as head trauma and headaches caused by swelling. In Kenya, some tribes’ healers still perform this procedure today for treatment of injuries and illness (Gross, 2021). Another point of evidence for spiritual purposes of trepanation is the amulets found in various locations around the world, made from human skull pieces that look very similar to those that would have been pulled from trepanned skulls found nearby. Again, it is worth noting this could have simply been a byproduct of a necessary procedure and some could have been carved from individuals’ skulls who were already deceased (Gross, 2021).

What is important to remember is that many of these assumptions of a spiritual motive behind ancient trepanation could stem from racist ideas or assumptions that ancient people were incapable of modern reasoning. Even papers addressing the fact that trepanation seemed to coincide with evidence of head trauma assumes that the people performing the surgeries were doing so to ‘release spirits’, rather than assuming that these people realized the act of making these holes saved the patient (Prioreschi, 1991). Assuming that our ancient ancestors were incapable of reasoning is a common and disproven assumption, thus, these discussions of spiritual motive for trepanation must be viewed with a wider lens (Villa & Roebroeks, 2014).  

… many of these assumptions of a spiritual motive behind ancient trepanation could stem from racist ideas or assumptions that ancient people were incapable of modern reasoning

Why is the history of trepanation important?

Trepanation is the earliest known example of what would ultimately become neurosurgery and, arguably, neuroscience. It is also a remarkable example of how innovative and logical our ancestors were. We often give medical practitioners of the past a bad rep, as it is easy to look back and scoff at what today would be ridiculous treatments for simply cured ailments. How could they possibly think that ‘bad air’ caused disease, or that you don’t need to clean the blood off your instruments before you use them again? But they were working off the information they had, just like we are today. It is arrogant to think that the people of the future will not look back on some of our medical practices and scoff at what we see as ‘modern’ medicine.

Trepanation shows us the strengths of human logic and observation. It makes an excellent example of how all of our current knowledge is built off of the mistakes and successes of the past. We did not get to our current level of medicine without a lot of trial and error, and the fact that we currently are able to perform complex neurosurgery is built off the backs of our ancestors’ efforts. Finally, trepanation is an important example of why we shouldn’t underestimate the people of the past. Writing things off as only for a ritualistic purpose strips humanity of the remarkable feats of survival they have been able to achieve. Remember that when we talk of humans of the past, we are talking about people identical to us – just with a different set of information at their fingertips.

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Written by Julia LaValley
Illustrated by Melis Cakar
Edited by Zoë Dobler, Chris Gabriel, and Honoreé Brewton

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References:

Arnott, R., Finger, S., & Smith, C. (Eds.). (2003). Trepanation. CRC Press. https://doi.org/10.1201/b16983 

Asadi-Pooya, A. A., & Rostami, C. (2017). History of surgery for temporal lobe epilepsy. Epilepsy & Behavior, 70, 57–60. https://doi.org/10.1016/j.yebeh.2017.02.020

Bower, B. (2018, February 6). Ancient kids’ toys have been hiding in the archaeological record. https://www.sciencenews.org/article/ancient-toys-kids-archaeological-record

Bronze Age skull from Jericho, Palestine, 2200-2000. (n.d.). Wellcome Collection. Retrieved July 25, 2023, from https://wellcomecollection.org/works/va96ydta

Chaloner, E. J., Flora, H. S., & Ham, R. J. (2001). Amputations at the London Hospital 1852-1857. Journal of the Royal Society of Medicine, 94(8), 409–412. https://doi.org/10.1177/014107680109400812

Chaves-Rivera, A., & Sanchez, T. (2022). Trepanation Reveals the Success of the Incas. ACS. https://www.facs.org/for-medical-professionals/news-publications/news-and-articles/bulletin/november-december-2022-volume-107-issue-11/from-the-archives/

Ghannaee Arani, M., Fakharian, E., & Sarbandi, F. (2012). Ancient Legacy of Cranial Surgery. Archives of Trauma Research, 1(2), 72–74. https://doi.org/10.5812/atr.6556

Gross, C. (2021, June 11). A Hole in the Head: A Complete History of Trepanation. The MIT Press Reader. https://thereader.mitpress.mit.edu/hole-in-the-head-trepanation/

Hobert, L., & Binello, E. (2017). Trepanation in Ancient China. World Neurosurgery, 101, 451–456. https://doi.org/10.1016/j.wneu.2016.10.051

Kushner, D. S., Verano, J. W., & Titelbaum, A. R. (2018). Trepanation Procedures/Outcomes: Comparison of Prehistoric Peru with Other Ancient, Medieval, and American Civil War Cranial Surgery. World Neurosurgery, 114, 245–251. https://doi.org/10.1016/j.wneu.2018.03.143

Missios, S. (2007). Hippocrates, Galen, and the uses of trepanation in the ancient classical world. Neurosurgical Focus, 23(1), 1–9. https://doi.org/10.3171/FOC-07/07/E11

Prioreschi, P. (1991). Possible Reasons for Neolithic Skull Trephining. Perspectives in Biology and Medicine, 34(2), 296–303. https://doi.org/10.1353/pbm.1991.0028

Reilly, R. F. (2016). Medical and surgical care during the American Civil War, 1861–1865. Proceedings (Baylor University. Medical Center), 29(2), 138–142. https://doi.org/10.1080/08998280.2016.11929390

Shim, Y. W., Lee, W. H., Lee, K. S., Kim, S. T., Paeng, S. H., & Pyo, S. Y. (2019). Burr Hole Drainage versus Small Craniotomy of Chronic Subdural Hematomas. Korean Journal of Neurotrauma, 15(2), 110–116. https://doi.org/10.13004/kjnt.2019.15.e25

Tullo, E. (2010). Trepanation and roman medicine: A comparison of osteoarchaeological remains, material culture and written texts. The Journal of the Royal College of Physicians of Edinburgh, 40, 165–171. https://doi.org/10.4997/JRCPE.2010.215

Villa, P., & Roebroeks, W. (2014). Neandertal Demise: An Archaeological Analysis of the Modern Human Superiority Complex. PLOS ONE, 9(4), e96424. https://doi.org/10.1371/journal.pone.0096424

Wade, L. (2018). South America’s Inca civilization was better at skull surgery than Civil War doctors. https://www.science.org/content/article/south-america-s-inca-civilization-was-better-skull-surgery-civil-war-doctors

Webb, S. G. (1988). Two possible cases of trephination from Australia. American Journal of Physical Anthropology, 75(4), 541–548. https://doi.org/10.1002/ajpa.1330750411

Wilberger, J. E., Harris, M., & Diamond, D. L. (1991). Acute subdural hematoma: Morbidity, mortality, and operative timing. Journal of Neurosurgery, 74(2), 212–218. https://doi.org/10.3171/jns.1991.74.2.0212 

Author

  • Julia LaValley

    Julia is a PhD student in the Neuroscience and Behavior program at UMass Amherst. Her research involves using florescent imaging paired with immunohistochemistry and in situ hybridization to investigate the neural centers responsible for sensory processing and motor control in invertebrate mollusks. In addition to her research, she is also active in the science policy and science communication fields. Outside of work, Julia enjoys going for hikes with her dogs, reading sci-fi, and trying new recipes. For more information, please visit her profile. (https://www.linkedin.com/in/julia-lavalley/)

Julia LaValley

Julia is a PhD student in the Neuroscience and Behavior program at UMass Amherst. Her research involves using florescent imaging paired with immunohistochemistry and in situ hybridization to investigate the neural centers responsible for sensory processing and motor control in invertebrate mollusks. In addition to her research, she is also active in the science policy and science communication fields. Outside of work, Julia enjoys going for hikes with her dogs, reading sci-fi, and trying new recipes. For more information, please visit her profile. (https://www.linkedin.com/in/julia-lavalley/)