Growth patterns of Labrador Inuit youth: II. Skeletal age.

Few studies have been conducted on skeletal maturity of circumpolar populations despite its importance as background knowledge to orthopedic and orthodontic procedures or for other medical problems involving endocrine disturbances. The purpose of this study was to compare skeletal age with chronological age of Labrador Inuit youth aged between 5-18 years and to compare these results with data from a national survey of United States youth. The sample included 32% (n = 100) of the Inuit youth living in Nain, Labrador, Canada (Male = 41, female = 59). Hand wrist radiographs, collected during a field study in 1991, were used to estimate bone age using the Greulich and Pyle bone specific method. The mean relative Inuit skeletal ages increased almost consistently with chronological age but showed considerable individual variation as shown by the 95% confidence intervals. The pattern of growth of skeletal vs chronological age was similar to the National Center for Health Statistics data but the tempo was slower. The Z-scores for mean male relative bone ages ranged from -0.7 to -1.9 and for females from -0.6 to -1.4. The results indicated that Inuit males started to reach adult skeletal maturity levels by the chronological age of 17 years 9 months, and Inuit females by 15 years 8 months. Generally, Inuit skeletal ages were delayed by 10-24 months behind the reference atlas skeletal ages and 9-22 months behind the Inuit chronological ages.(ABSTRACT TRUNCATED AT 250 WORDS)