Are sinuses shock absorbers?
As discussed previously, sinuses or a vaulted frontal could absorb shocks to the brain by two general mechanisms: (1) dissipating the energy of impact before it reaches the endocranial cavity; and (2) directing strain (and stress) away from the bone lining the endocranial cavity. Evidence supporting such a protective function was mixed. If sinuses (or a vaulted frontal) have a major role in storing energy, models with these structures should show elevated strain energy in the frontal. Strain energy was always greatest for models with sinuses, appearing to support their suggested role in shock absorption. But a vaulted frontal alone did not always confer an advantage – under double-horn loading in particular, models with solid vaulted frontals stored a much lower proportion of the strain energy within the frontal than did the model with unvaulted frontals. Thus, a sinus in combination with a vaulted frontal, rather than a vaulted frontal alone, was needed to maximize the shock absorptio
