Spondylolysis in Inuit skeletons from Arctic Canada

Abstract

Inuit skeletons from archaeological sites in Arctic Canada were examined for the presence of spondylolysis. The largest series represent the Thule culture and historic Inuit from northwest Hudson Bay and Labrador, and Sadlermiut from Southampton Island. The condition was found in 90 individuals, with a total of 120 affected vertebrae producing 198 hemi-arch defect sites.As in other studies, L5 is affected most frequently, followed by L4 and L3, but examples of L1, L2, L6, and S1 involvement are represented. Incomplete separations account for 20% (40) of the 198 defects, and 5% (10) occur at sites other than interarticularis. Affected males outnumber females at a ratio of 2.4 to 1. The condition was found to increase in frequency from adolescence to young adulthood, and then decrease to middle adulthood and decrease again to old adulthood, but the drop in frequency with age in the adult categories is significant only at the .20 level. Where comparisons could be made, the data obtained from the Canadian Inuit closely resemble those obtained from Alaskan Eskimos and Aleuts, especially their closest linguistic relatives, Inupiat speakers in northern Alaska.

Lumbar vertebral morphology and isthmic spondylolysis in a British medieval population

“…Burials here span the 10th-19th centuries AD, but are predominantly from 11th to 14th centuries (Bayliss et al, 2007). This is not the highest known population frequency, as Inuit populations are reported to have a prevalence of 40% or higher (reviews in Merbs, 2002;Fibiger and Knü sel, 2005). Still, it highlights differences among populations in the prevalence of these defects.…”

“…Higher activity levels have been suggested as a potentially influential factor (review in Mays, 2006b), as defects are often more frequent in archaeological than in modern populations (Merbs, 1983;Bridges, 1989;Arriaza, 1997;Merbs, 2002;Fibiger and Knü sel, 2005). Certainly, the occurrence of spondylolysis is influenced by mechanical variables (Nathan, 1959;Wiltse, 1962;Newman, 1963;Wiltse et al, 1975;Cyron et al, 1976;Farfan et al, 1976;Cyron and Hutton, 1978;Cyron et al, 1979;Troup, 1979;Dietrich and Kurowski, 1985).…”

Spondylolysis in a pre‐contact San Francisco Bay population: behavioural and anatomical sex differences

“…Following Merbs (2002), the author noted the presence or absence of the condition, when it occurred, whether the separation was partial or complete, which vertebrae were affected, whether the condition was unilateral (along with the side it occurred on) or bilateral, and whether there was evidence of healing.…”

“…Another interesting twist is that as individuals grow very old, spondylolysis seems to decrease. Merbs (2002) noted that the decrease in spondylolysis rates in older adults could relate to the healing of fractures, and thus prior spondylolysis escapes detection. However, this must be coupled with older individuals ceasing their strenuous activities, since Reiter et al (2006) and Bridges (1989) have both found spondylolysis in elderly individuals.…”

“…Bridges (1989) tied spondylolysis to non-specific activities related to hunting and gathering. Merbs (1983Merbs ( , 1996bMerbs ( , 2002 noted that the high percentage of spondylolysis in Arctic populations is related to heavy labour required to live in those cold climates, such as lifting heavy items, kayaking, paddling and wrestling. Yet, one must note that many anthropologists agree it is difficult to tie specific activities to spondylolysis, and even in sports the predictive rate of spondylolysis with an activity is very low (Bridges, 1989;Merbs, 1996a;Jurmain, 1999).…”