Distal radial growth plate injury and positive ulnar variance in nonelite gymnasts.

To assess the prevalence of stress injury to the distal radial growth plate and of positive ulnar variance in a nonelite gymnast population, we administered a radiographic survey and questionnaire to 44 skeletally immature nonelite gymnasts (27 girls and 17 boys). The subjects trained an average of 11.9 hours per week. Radiographic findings consistent with stress injury of the distal radial physis were found in 25% (11 of 44) of participants. Ulnar variance was found to be more positive in the gymnasts when compared with age-predicted norms. An average side-to-side difference in ulnar variance of 0.9 mm was observed. Radiographic findings of stress injury to the growth plate and the amount of ulnar variance were not associated with age, sex, training intensity, wrist pain, height, or weight. There was also no significant relationship between ulnar variance and radiographic findings. The mean ulnar variance in nonelite gymnasts was between that measured for elite gymnasts and nongymnasts. These results indicate that stress injury of the distal radial growth plate occurs in a significant percentage of nonelite gymnasts. It also appears that ulnar variance is more positive than would otherwise be predicted, suggesting growth inhibition of the distal radius, a growth stimulation of the ulna, or a combination of both.