AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 98:203-209 (1995) Brief Communication: Earliest Cranial Surgery in North America GARY D. RICHARDS Department of Anthropology, Laboratory for Human Evolutionary Studies, University of California, Berkeley, California 94720-3712 KEY WORDS pericranii Prehistory, California, Vascular anomalies, Sinus ABSTRACT The archaeological evidence of ancient cranial surgery is limited to cases of trepanation and cauterization. I report here on the only known case of cranial surgery in direct association with the osseous image of a nontrauma-induced soft tissue lesion (sinus pericranii). This case, from Alameda County, California (Late Middle Period, ca. 300-500 AD), is the earliest and only definitive evidence of invasive surgery from prehistoric North America.' Because this individual presents the only bony evidence of cranial surgery other than trepanation or cauterization, it contributes substantially to our extremely limited understanding of medical practices in preliterate societies. 0 1995 Wiley-Liss, Inc. More than a century ago, Paul Broca published the first evidence of prehistoric cranial surgery (Broca, 1867). This evidence from Cuzco, Peru, was soon followed by descriptions of other apparent cases of trepanation (cranial vault fenestration) from numerous worldwide localities (Lisowski, 1967; Prunieres, 1874). Subsequently, a second form of surgery, cauterization (localized cranial vault burning), was described in French populations of Neolithic age (Manouvrier, 1895; Moodie, 1921). These are the only types of prehistoric cranial surgeries documented. An overview of the relationship between primitive and modern surgical practice is provided by Ackerknecht ( 1947x2 In North America, the evidence of cranial surgery is limited to 20 purported cases of pre-Columbian trepanation (Canada = 12; USA = 8) (Cosgrove, 1929; Cybulski, 1980; Griffin, 1976; Hinsdale and Cappannari, 1940; Hinsdale and Greenman, 1936; Kidd, 1946; Leechman, 1944; Miller, 1994a,b, 1995; Moodie, 1930; Morse, 1978; Nieburger, 1978; Powell, 1970; Shapiro, 1927; Stewart, 1957; Stone and Miles, 1990; Wakefield and Dellinger, 1939). With a single exception (Miller, 1994a,b, 19951, however, none of these cases shows evidence of a directly asso0 1995 WILEY-LISS, INC. ciated fracture, lesion, or anomaly (Cybulski, 1978, 1980; HrdliEka, 1932; Ortner and Putschar, 1985; Stewart, 1957, 1975a,b; Stone and Miles, 1990). Miller (1994a,b, 1995) presents two cases that she considers to demonstrate trepanation following scalping. While these cases are provocative, the bony evidence does not allow for elimination of nonsurgical trauma as a source of the cranial perforations. Therefore, none of the available examples can be considered a surgical intervention; rather, they can be ascribed to postmortem trepanation, trauma, natural (taphonomic) processes, or pathological processes (Cybulski, 1978, 1980; HrdliEka, 1939; Leechman, 1944; Stewart, 1957, 1957a,b, 1976; Wakefield and Dellinger, 1939). Historically, the presence of two features, Received September 15, 1994; accepted May 8, 1995. 'Throughout this work, all reference to North American evidence excludes cases from south ofthe border between the United States and Mexico. 2Here and in what follows, surgery denotes any procedurek) that would generally fail in the domain of the modern Western surgeon Address reprint requests to Gary D. Richards, Department of Anthropology, University ofCalifornia, Berkeley, CA 94720-3712. 204 G.D. RICHARDS cicatrization (healing)of the bone and associated evidence of a pre-existing lesion, has been considered diagnostic of surgical intervention intended to remove diseased or destroyed tissues. Numerous examples of trepanation in association with cranial fractures and, possibly, some cases of osteoperiostitis following trauma-induced periosteal destruction are known from other geographic regions. My literature review indicates that no prehistoric examples exist, worldwide, which unambiguously demonstrate the association of non-traumainduced lesions with evidence of cranial surgery (Ackerknecht, 1947; Cave, 1940; Fletcher, 1882; Gillman, 1876, 1885; Janssens, 1970; Moodie, 1923; Mufiiz and McGee, 1897; Nadaillac, 1894; Parrot, 1881; Piggot, 1940; Rogers, 1938; Smith, 1924; Tello, 1912). Alternatively, note that some preexisting conditions may be aggravated by trauma, and that this may have provided the rationale for surgery (see below). MATERIALS AND METHODS The focus of this report is a n individual recovered in 1924 during salvage excavations at the Emeryville Shellmound, Alameda County, California (CA-Ala-309; Fig. 1). The remains consist of the skull of a male individual (Phoebe Hearst Museum of Anthropology (PHMA); 12/3619),determined to have been 30 ( 5 5 ) years of age. Determination of the individual’s sex follows criteria outlined in Bass (1987). The age determination is based on dental calcification and eruption patterns (Ubelaker, 1978), providing a n age assessment of >21 years of age, and on comparable dental wear, providing a n age assessment of 25-35 years of age, as sequenced for this sample population by myself. The latter process is based on the entire skeletal series from the Ala-309 locality for which cranial and postcranial indicators of age are available. The dentitions of these individuals were sequenced with reference to wear stages provided by Brothwell (1981). Age determinations provided for the Brothwell (1981) series were modified for consistency with the Ala-309 sample population. I examined crania from Peru (n = 1,000: PHMA), of which 32 (3.2%) had a total of 53 Fig. 1. Locality map showing the Emeryville Shellmound (CA-Ala-309: 0) and some larger sheilmounds (0) formerly present around the San Francisco Bay. trepanations. These individuals were examined in order to evaluate the relationship of vascular hypertrophy to pathological processes of the cranial vault. The level of vascular response, as delimited by observable bony impression(s), to surgical interventions (trepanations)was also evaluated. Individuals included in the Peruvian series derive from multiple prehistoric sites in the following Peruvian localities; Allangay, Ancon, Cajabanba, Chala, Chancay, Chanchan, Chicama, Chincha, Cuzco, Ica, Lima Valley, Limatambo, Marca Hua, Moche, Mochica, Ocucaje, Ocucye, Oroaa, Pachacama, Pampa Pac, Pampa Qui, Pisco, Supe, Tarmatamb, Trujillo, Viracocha, and Yauca. The Emeryville remains are dated to 300500 AD on the basis of associated Sherwood Phase (Late Middle Period) artifacts, including the co-occurrence of Olivella Oval Saddle (type F2b) and Square Saddle (type F3a) beads and edge-incised but unperforated rectangular abalone ornaments. Artifact dating is based on regional seriation studies that incorporate numerous carbon-14 and obsidian hydration dates from other local mounds (Fig. 1: Bennyhoff, 1986). Recent PREHISTORIC SURGERY carbon-14 dating of a n associated abalone (Haliotis rufescens)pendant produced a n age estimate of 950 -C 50 years BP (AA10587). This inconsistent age determination indicates a high level of carbonate contamination in the shell sample. 205 sistent with cuts made by stone tools (Bunn, 1981, 1984; Oliver, 1989; Potts and Shipman, 1981; Shipman and Rose, 1983a,b). Striae were both preceded and removed in places by the slicing or chiseling action of a sharp implement. The latter processes resulted in the removal of minimal amounts of osseous tissue. Nearly complete DESCRIPTION removal of the ectocranial surface occurred The skull suffered restricted areas of post- superolaterally, however, due to a boring or mortem erosional damage, but bone in the drilling action (Fig. 2B,C). affected area is well preserved and easily Obsidian microchips were embedded in observed in postmortem fracture sections. I n the bone during the boring or drilling proa n ovate area (2.0 x 4.0 cm) on the frontal cess. Two microchips are embedded in what bone's midline, cultural activity is superim- now constitutes the superficial lamella to apposed on a region of bony response to patho- proximately one-half their thickness. A third logical processes (Fig. 2A-C). This region ev- microchip is embedded in the deeper lamelidences high vascularity, being dominated by lae of the ectocranial cortex (Fig. 2B-Cl). large vascular impressions. The ectocranial Examination of the microchips and sursurface is marked by a prominent, U-shaped rounding bone with a light microscope (XOdefect resulting from expansion of pericra- 80) demonstrates that all three are firmly nial and emissary vessels. These vascular embedded in compact cortical bone. That impressions enter the diploic space supero- these microchips are embedded in the bone laterally, where the entire ectocranial sur- and are distinct from potentially adhering face is absent. The pericranial and emissary sediments is further supported by their convascular impressions are also connected to tinued presence following two separate enlarged diploic channels via a series of cleanings (1924, 1991). Cleaning occurred small foramina in the impressions. The en- prior to recognition of the cultural activity docranial surface does not show deep vascu- and in all probability resulted in the loss of lar erosion but rather a n increase in the other microchips. Embedded microchips are number and diameter of foramina (>2.0 not known in other cases of prehistoric surmm) exiting the affected diploic space. No gery. Their presence here is believed to relate other pathological processes are apparent on to the unique nature of the pathologic lesion either gross or radiographic inspection. In and to derive from microfracturing of the sum, the bony evidence is an isolated, well- tool's edge during a n attempt to remove the demarcated region of abnormally large vas- main vascular trunk with a boring or drillcular impressions connected superolaterally ing action. to enlarged diploic vascular channels. Ectocranial porosity surrounding portions The superimposed cultural activity con- of the lesion and the presence of necrotic sists of a n extensive series of inferomedially and resorbed trabeculae a t the superolateral directed parallel striations and plateaus oc- edge of the defect indicates the presence of curring only between arms of the U-shaped septic necrosis. Apart from surgical intervascular markings (Fig. 2B,C). Striations ex- vention, no other processes are apparent tend from a n intimate contact with the su- that account for the necrosis. Extended surperomedial extent of the vascular markings vival is not indicated due to the lack of a to the extreme inferomedial extent of the significant halo of porosity (Stewart, 1956, vascular impressions. Striae do not cross or 1957) and remodeling of the affected area. enter the vascular markings (Fig. 2B,C). The These features are helpful in gauging postmedial-most portion is marked only by mul- operative survival in cases of scalp removal. tiple, finely incised linear striae. Under a Remarkably, however, the possibility of poststandard light microscope ( x 0-80), the operative surgical closure of the scalp exists striae exhibit shoulder effects and small stri- in this case (Fig. 2A). Closure of the wound ations within the main striae, criteria con- following a surgical procedure encourages Fig. 2. A,Three-quarter view of the frontal region of the study individual (PHMA 12/3619). The external circumference of the vascular impressions is marked by open arrows. The extent of the incision(?)or skin flap(?) is marked by closed arrows. Note the overall symmetry and the discrete nonvascular boundary in the region marked by closed arrows. Minor amounts of periosteal bone deposition occur at the inferolateral extent of the lesion (1).B: Closeup view of the cultural activity and vascular impressions. Two methods of bone removal are documented in the long linear cuts, indicating a slicing motion (l),and the more flattened areas, indicating the use of a chisel-like motion (2). A third method of bone removal occurs where the main vascular trunk formerly exited the diploic space (3). The associated “foramen” is now ringed with cuts resulting from a boring or drilling action. C: Line drawing of the detail observed in Figure 2B. Obsidian microchips are embedded in the bone (1). Observe the rampart on the medial surface of the vascular impression and note that the cuts do not enter or cross it (2). Formation of a halo of porosity indicates the presence of a septic necrosis, which is in its early stages as denoted by the patchy and limited extent of ectocranial porosity (3). PREHISTORIC SURGERY 207 crania from Peru clearly shows that this is a distinct vascular condition and not a normal response to surgical insult. Ethnohistorical accounts document that certain native North American groups were well versed in, and regularly applied, surgiDISCUSSION cal principles (Freeman, 1918). Setting of Virulent soft tissue infections and rapidly fractures, reduction of dislocations, removal growing cysts or boils are unlikely causes of of projectiles, and the cleaning, suturing, the pathological condition given the level and management of suppurative wounds of periosteal and cortical involvement. were among the procedures practiced. Given Chronic, localized low-grade infections, this wound’s symmetry (Fig. 2A), the nature slow-growing cysts, congenital or trauma- of the lesion, and the historic record of heminduced vascular conditions, or benign tu- orrhage control in native groups, it is possimors of the scalp are more likely causes. ble that the surgical wound was cauterized These conditions could produce general pres- or packed to promote coagulation and slow sure atrophy of cortical bone without signifi- hemorrhage (Freeman, 1918; Hefferman, cant periosteal reaction. Evidence of such 1896; Rifiinson-Mann, 1988). Evidence reatrophy is not apparent but may have ex- garding the medical knowledge of the diisted prior to bone removal procedures. The verse native San Francisco Bay populations hypervascularity suggests the condition is essentially nonexistent. The ethnohistory probably results from sinus pericranii, a vas- of similar but regionally and temporally recular anomaly. This pericranial lesion is gen- moved California groups documents only the erally believed to be of congenital origin practice of blood-letting (Yokuts, Gabrielino) (uarix communicans) but may appear follow- and the application of various plants and ing head trauma (uarix spurius communi- plant extracts in the treatment of ailments cans), although the underlying vascular (Gabrielino: Kroeber, 1976). These were auganomaly is probably already present (Cour- mented by ritualized activities, including ville, 1947). Sinus pericranii presents as a n the sucking-out of disease objects and the asymptomatic swelling of the scalp which blowing of smoke (Kroeber, 1976). The usual is usually about 2.0-3.0 cm long. Palpable purpose of these procedures was the removal rarefication of the ectocranial cortex due to of a contained entity(s), a practice docupressure atrophy, resulting from increasing mented in California and most regions of vessel size, is present in this condition. The the world (Clements, 1932; Lisowski, 1967; enlarged pericranial, emissary and diploic Margetts, 1967). The lesion’s benign nature vessels are connected to the superior sagittal indicates that invasive procedures were not sinus by a series of smaller vessels that feed undertaken to alleviate actual, a s opposed blood into the sinus at a n abnormal pressure to perceived, symptoms. This individual may or rate (Courville, 1947). This condition is have suffered from another condition that similar to a n arteriovenous (cirsoid) aneu- led to surgery on this outward sign of a conrysm but is smaller, less impressive, and not tained entity(s1. Supporting this is the fact accompanied by a persistent roaring (bruit) that sinus pericranii is a rare condition in the ears (Courville and Rocovich, 1946). (Courville and Rocovich, 1946; Hahn, 1928) Differential diagnoses include hemangioma and one unlikely to have been frequently encountered in prehistoric populations. and recently acquired cirsoid aneurysm. In evaluating prehistoric surgical interventions, one must consider the possibility CONCLUSION that osteological manifestations of pathologic processes are a consequence of cultural Results of the cultural activity preserved modifications undertaken for symbolic rea- in the cranial remains bear directly on our sons alone. The hypervascularity would then extremely limited understanding of medicohave to be attributed to normal healing fol- surgical and medicoreligious practices in lowing surgical insult. My examination of this group and related groups. In a wider healing by minimizing bony response to trauma and infection. This, then, makes it difficult to detect such events and to determine the length of postprocedure survival. 208 G.D. RICHARDS context, the preserved resultant of this activity provides insight into questions both of the spread of surgical knowledge, for both medical and religious reasons, and of the independent development of this knowledge in geographically distributed population centers. While trepanation is frequently broadly defined in prehistoric contexts (Clements, 1932; Margetts, 1967), intervention in this case is not a trepanation (sensu stricto). Bone removal in this instance resulted from aggressive surgical intervention, most probably dictated by the surgeon’s response to the profuse and steady bleeding following removal of the expanded veins. While the anatomical evidence and current medical knowledge provide little rationale for intervention in this case, its occurrence is clearly documented. This individual from California provides the only prehistoric evidence, worldwide, of a n attempt to remove a non-trauma-induced soft tissue defect. ACKNOWLEDGMENTS I thank Tim D. White, Rebecca S. Jabbour, Susan C. Anton, David R. Begun, F. Clark Howell, Douglas H. Ubelaker, John W. Verano, Rose Tyson, James A. Bennyhoff, and Larin Pesavento for discussion and review of the manuscript; Gene Prince and PHMA staff, University of California a t Berkeley (UCB) for access to skeletal, photographic, and artifactual material; Betty Clark, Cowell Memorial Hospital, UCB and Will Forbes, University of the Pacific, School of Dentistry for radiographs. Funding for curating the Berkeley Primate Skeletal Collection was provided by National Science Foundation (NSF) Systematic Collections grant BNS8907967. NSF and the University ofArizona provided and funded the carbon-14 age determination. LITERATURE CITED Ackerknecht EH (1947) Primitive surgery. Am. Anthropol. 49:25-45. Bass WM (1987) Human Osteology: A Laboratory and Field Manual. Columbia: Missouri Archaeological Society. Bennyhoff JA (1986) The Emeryville site, viewed 93 years later. Arch. Calif. Prehist. 6:65-74. 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