Measurements of axial rotation and translation of the fragments in thirty patients with fractures of the femoral shaft and condylar regions, using a specially designed electrogoniometer and cineroentgenography, were made while patients were in bed (in skeletal traction, in suspension without traction, and in a cast-brace), and while they walked in a cast-brace. Rotation in bed was less in the cast-brace than in traction or suspension, and with two exceptions was less walking in the cast-brace than in traction in bed. Translation during weight-bearing in the cast-brace was least with the supracondylar-intercondylar and mid-shaft comminuted fractures, and most with the mid-shaft transverse fractures. Based on these observations, we concluded that closed reduction and early ambulation in a cast-brace are best suited for fractures in the distal part of the femur and for comminuted multifragmented fractures in the middle and proximal part of the shaft.