Spondylolysis and associated spondylolisthesis in Eskimo and Athabascan populations.

Roentgenographic and anthropologic studies have shown a high incidence of spondylolysis in Eskimo populations. It is uncertain whether this is related to a genetic predisposition or to environmental factors. This study of recent roentgenograms and demographic characteristics of patients of the authors' institution notes a lower incidence in Eskimo populations than prior skeletal and roentgenographic studies. An attempt is made to quantitate the contributions of environmental factors and genetic predisposition. A higher incidence was found in full-blooded Eskimos than in part-blooded Eskimos. Rural-dwelling Eskimos had a higher incidence than urban-dwelling Eskimos. Eskimo subpopulations had a greater incidence than Athabascan Indians. Eskimos with spondylolysis were significantly more likely to have an associated spondylolisthesis than Athabascans with spondylolysis. Symptoms in the Eskimo population related to spondylolysis and associated spondylolisthesis rarely warrant surgical intervention.