Evaluation of pediatric trigger thumb in the Hispanic population at a southwest urban medical center.

BACKGROUND: Possible ethnic differences in the incidence of trigger thumb have not been studied in the literature. The authors' purpose was to examine the demographic characteristics of pediatric trigger thumb at a large urban medical center with a diverse patient population.

METHODS: The electronic medical records were reviewed for all children with trigger digit seen at Children's Medical Center Hand Clinic in Dallas from September of 2005 to May of 2008. All patients with trigger thumb were included in the study, and patients with trigger digit(s) alone were excluded. Population distributions were analyzed using chi-square analysis. Relative incidences were calculated and compared using the binomial method of standard error calculation.

RESULTS: A total of 97 patients with trigger digit(s) were identified. Of those, there were 87 patients with 96 trigger thumbs. The ethnic distribution of the trigger thumb group was 18 percent white, 7 percent black, 56 percent Hispanic, and 18 percent other. During the same time period, the authors' clinic evaluated 6667 new patients with an ethnic distribution of 26 percent white, 18 percent black, 38 percent Hispanic, and 18 percent other. A chi-square analysis comparing the ratios of the two groups revealed a value of p = 0.004. Overall trigger thumb incidence in our clinic was 1.3 percent, with ethnic breakdown of white, 0.9 percent; black, 0.5 percent; Hispanic, 1.9 percent; and other, 1.3 percent. The standard error was 0.14 percent, with a 95 percent confidence interval of 1.02 to 1.58 percent.

CONCLUSIONS: There was a higher incidence of trigger thumb in the Hispanic population. A lower incidence among blacks with trigger thumb was also noted.