A Clinical Study of the Distribution and Morphology of Harris Lines

Harris lines are commonly used in bioarcheology to infer lifestyle in ancient populations; however, their etiology and identification parameters are still under debate. The aim of this study is to observe the distribution of the lesions in a contemporary clinical sample to address their association with etiological factors, age, biological sex, and biogeographical origin. The sample consisted of 561 living individuals from Italy (n = 268) and Sri Lanka (n = 293). Radiographic images of long bones (humerus, radius, ulna, femur, tibia, fibula), and information on biological sex and age were collected. Statistical analysis was conducted using Fisher's test, chi-square tests, and odds ratios. Harris lines were significantly more frequent in bones of the lower limb (p < 0.001), and among Sri Lankan (32%) rather than Italian-grown individuals (20%) (p = 0.001). No statistically significant differences between sexes were observed (p = 0.790). No linear trend was found in the distribution of the lesions among age groups; however, their presence was attested among the oldest individuals (>80 years), challenging assumptions about bone remodeling and the evanescence of Harris lines. Additionally, morphological variation in radiopaque lesions was documented. The equal distribution between sexes is coherent with the characteristics and the contextual information of the samples, where no sex-based disparities are reported. This sheds new light on the impact of female biological buffering, as well as enforcing the interpretative role of Harris lines in detecting inequalities between females and males. The differences observed among the two geographical subgroups may be related to the socioeconomic context of growth, highlighting the capacity of Harris lines to reflect variations in access to resources.