In a retrospective survey of eighty-two children with supracondylar
fractures of the humerus, forty were found to have sufficient clinical and
roentgenographic data to classify the fractures as varus or valgus, and to
determine the carrying angles at end result. The initial displacement
(varus or valgus) of the distal fragment correlated with the final carrying
angle, but the use of internal fixation, the adequacy of reduction achieved
and the duration of traction or immobilization did not. The sixteen varus
supracondylar fractures immobilized with the forearm in supination had a
mean varus deformity of about 16 degrees, whereas the eight immobilized in
pronation had a varus deformity of only 3 degrees. The findings in the few
valgus fractures suggested that the valgus angulation was less at follow-up
if they had been immobilized in supination. Dissection of eight cadaver
limbs and electromyographic studies of one normal limb suggested that the
position of the forearm affects the result by altering muscle tension.