In the DB group , side-to-side anterior tibial shifts at a pressure of 124 N ( medians = 1.3 mm and 2.1 mm for DB and SB groups , respectively ; p = 0.0007 ) and at a pressure of 250 N ( DB group = 2.1 mm ; SB group = 3.1 mm ; p < 0.0001 ) were significantly different from the corresponding values in the SB group .