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Positive Ulnar Variance

How much variance is tolerated before symptoms ensue? A study of 163 distal forearm physeal fractures in patients who averaged 11.6 years old (range 5 to 17) at the time of injury were followed up for an average of 25.5 years (range 14 to 46). At follow-up, all the patients were fully asymptomatic, except for the 10 patients who had forearm bone growth failure of more than 1 cm.[22] Therefore, radioulnar discrepancy of less than 1 cm is often well tolerated and does not require routine operative management unless symptoms are present.

Positive ulnar variance is usually more symptomatic than negative ulnar variance. Positive variance is due to growth arrest of the radius and relative overgrowth of the ulna. Most patients complain of ulnar-sided wrist pain with exacerbation during ulnar deviation and/or forearm rotation. In addition, the appearance of the elongated ulna is a common complaint. The standard tests for instability and impaction in the adult are applicable …