At @ weeks after surgery there were no significant differences between usual care and HEP , respectively , for pain ( @ and @ ; @ % CI mean difference -LSB- MD -RSB- -@ , @ ) , physical function ( @ and @ ; @ % CI MD -@ , @ ) , knee flexion ( @ and @ ; @ % CI MD -@ , @ ) , knee extension ( -@ and -@ ; @ % CI MD -@ , @ ) , or the @-foot walk time ( @ and @ seconds ; @ % CI MD -@ , @ seconds ) .