Learning to Resist Gait-Slip Falls: Long-Term Retention in Community-Dwelling Older Adults  Tanvi Bhatt , PT, PhD, Feng Yang , PhD, Yi-Chung Pai , MPT, PhD  Archives of Physical Medicine and Rehabilitation  Volume 93, Issue 4, Pages 557-564 (April 2012) DOI: 10.1016/j.apmr.2011.10.027 Copyright © 2012 American Congress of Rehabilitation Medicine Terms and Conditions

Fig 1 A flow diagram demonstrating subject recruitment and progress through the various phases of the study. Subjects were excluded if T score on calcaneal ultrasound was greater than −1.5 and if mobility score quantified by the Timed Up and Go test was greater than 13.5 seconds. Intervention consisted of the repeated slip-nonslip training protocol. Ancillary slip was a single slip given to subjects in the dual-session group. Archives of Physical Medicine and Rehabilitation 2012 93, 557-564DOI: (10.1016/j.apmr.2011.10.027) Copyright © 2012 American Congress of Rehabilitation Medicine Terms and Conditions

Fig 2 (A) The protocol is shown for the 2 groups: single-session and dual-session perturbation training. Note that both groups received similar initial session perturbation training at 0 week (0wk). Both groups received a retest consisting of a single slip at the 6-month interval. The dual-session group received the initial training followed by an ancillary session consisting of a single slip at the 3-month interval. The perturbation training consisted of 24 slips total delivered in block and random fashion. Blocks of slip trials are shown in gray, blocks of nonslip trials (NS) in white, and the block of mixed slip and nonslip trials is shown by vertical lines. The sequence of trials comprised 10 initial nonslip trials, followed by a block of 8 slips, a block of 3 nonslip trials, a second block of 8 slips, a second block of 3 nonslip trials, then a mixed block of 8 slip and 7 nonslip trials. All trials were unannounced, and subjects were only aware that a slip “may or may not occur.” (B) Video sequence demonstration of an older subject who fell after a slip after stepping on the low-friction platform that was released unexpectedly during walking, shortly after right touchdown. The sequence was taken from the first slip of the initial training session on which the subject experienced a fall. (C) Video sequence of the same subject when he returned after a 6-month interval after initial session. Note that the subject did not experience a fall or a balance loss but was able to successfully continue walking under slip conditions (ie, platform released). (D) Video sequence of another subject on the first slip of training session demonstrating a BLOB with a compensatory recovery step landing posterior to the slipping limb. For B, C, and D, images 1 through 3 correspond to events of right touchdown preceding onset of slip, postslip liftoff, and touchdown of contralateral limb. B1–4 corresponds to fall termination, C1–4 to slipping foot liftoff, and D1–4 to trailing foot liftoff. Archives of Physical Medicine and Rehabilitation 2012 93, 557-564DOI: (10.1016/j.apmr.2011.10.027) Copyright © 2012 American Congress of Rehabilitation Medicine Terms and Conditions

Fig 3 Incidence of (A) falls and (B) backward balance loss in percentage (%), (C) postslip stability and (D) hip height (mean + SD), demonstrated on the first slip and last slip of the initial training session (S1 and S24, respectively) and the 6-month retest slip (6-mo) for the 2 participating groups: single session (training only, open squares) and dual session (training + ancillary session; filled circles). These variables are also demonstrated for the dual-session group on the ancillary single slip at the 3-month interval (3-mo). *P<.05 and **P<.01 for the independent and paired t tests performed. Solid lines indicate comparisons within single-session group and dashed lines within dual-session group. Archives of Physical Medicine and Rehabilitation 2012 93, 557-564DOI: (10.1016/j.apmr.2011.10.027) Copyright © 2012 American Congress of Rehabilitation Medicine Terms and Conditions