Differentiating between rhinosinusitis and mastoiditis surgery from postmortem medical training: A study of two identified skulls and hospital records from early 20th century Coimbra, Portugal

•This study presents evidence of medical procedures to rhinosinusitis and mastoiditis during the first half of the 20th century in Coimbra (Portugal).•Confirmed evidence of surgical trepanation to treat rhinosinusitis may suggest lesions that can identify possible frontal sinus disease in other osteological assemblages.•The osteological examples in this study are framed in their respective medical contexts in the Coimbra University Hospitals.

Differentiating between medical procedures performed antemortem, perimortem or postmortem in skeletal remains can be a major challenge. This work aims to present evidence of procedures to treat rhinosinusitis (RS) and mastoiditis, suggest criteria for the diagnosis of frontal sinus disease, and frame the individuals described in their medical historical context. In the International Exchange collection, the skull (878) of a 24-year-old male, who died in 1933 due to frontal sinusitis and meningitis, presents evidence of a trepanation above the right frontonasal suture, and micro/macroporosity on the superciliary arches. The available Coimbra University Hospitals archives (1913-1939) reported that 46 females and 59 males (aged 15 months-84 y.o., x̄ = 35.33) underwent surgery to treat RS, primarily by trepanation (94.3%). In a search for similar evidence in the collection, the skull of a 42-year-old female (85), who died in 1927 due to sarcoma in the abdomen, shows four quadrangular holes located above the right supraorbital notch, right and left maxilla, and left mastoid process. The number/location of the holes and cut marks point to postmortem medical training (possible dissection). This paper discusses the value of information from historical contexts to differentiate between surgery and medical training in the paleopathological record.