KE McCAFFERTY, DM MITTLER, DP VAN GERVEN AND SG SHERIDAN, Department of Anthropology, University of Colorado, Boulder

Previous analyses of degenerative joint disease (DJD) in skeletal populations have established an association between subsistence behaviors and the expression and development of DJD.  The Hohokam, with a well documented agricultural economy, provide an excellent opportunity to investigate this further.  The purpose of this research was to examine the pattern of DJD, specifically vertebral osteophytosis, and its relationship to patterns of subsistence and reproduction at the Hohokam site of Pueblo Grande.

Vertebral column from 30 females and 31 males were selected for analysis.  Ages ranged from 18 to 50+ years.  Severity of osteophyte development was scored using a six stage, ordinal scale, modified from Kilgore (1985) and Chapman (1972).  A between and within vertebral region analysis was completed comparing the location and severity of vertebral osteophytosis across age and sex categories.

The results demonstrate a high incidence of vertebral DJD in the Pueblo Grande population with 93% of the females and 90% of the males exhibiting at least slight (stage I) osteophytosis.  Analysis by vertebral region showed a heightened rate of moderate to severe lesion development in the lumbar vertebrae for both males and females.  Within the lumbar spine, L4 is the most severely affected.  This patterns of increased lumbar and particularly L4 involvement is most likely to occur when the lower back is exposed to impulse loading associated with load carrying.

Analysis by sex revealed a higher female incidence for all stages of osteophytosis for all ages, through the vertebral column.  This pattern is consistent with the combined effects of rapid premenopausal osteopenia  (Kuzawa, et al., 1991) related to reproductive stress, and the strains of load carrying associated with both subsistence and reproduction.  This interpretation is supported further by a significantly higher frequency of vertebral body lesions and prolapsed vertebrae in the female sample.