Effects of moveable platform training in preventing slip-induced falls in older adults

Abstract

Identifying effective interventions is vital in preventing slip-induced fall accidents in older adults. The purpose of the current study was to evaluate the efficacy of moveable platform training in improving recovery reactions and reducing fall frequency in older adults. Twenty-four older adults were recruited and randomly assigned to two groups (training and control). Both groups underwent three sessions including baseline slip, training, and transfer of training on a slippery surface. Both groups experienced two slips on a slippery surface, one during the baseline and the other (after 2 weeks) during the transfer of training session. In the training session, the training group underwent twelve simulated slips using a moveable platform while the control group performed normal walking trials. Kinematic, kinetic, and EMG data were collected during all the sessions. Results indicated a reduced incidence of falls in the training group during the transfer of training trial as compared to the control group. The training group was able to transfer proactive and reactive control strategies learned during training to the second slip trial. The proactive adjustments include increased center-of-mass velocity and transitional acceleration after training. Reactive adjustments include reduction in muscle onset and time to peak activations of knee flexors and ankle plantar flexors, reduced ankle and knee coactivation, reduced slip displacement, and reduced time to peak knee flexion, trunk flexion, and hip flexion velocities. In general, the results indicated a beneficial effect of perturbation training in reducing slip severity and recovery kinematics in healthy older adults.

Figure 1

a. Experimental set-up for the baseline and transfer of training session including the walkway, harness, markers, two force plates (F1 and F2), and motion capture system,b. Experimental lay-out of moveable platform training set-up with the motorized platform and force plate.

Figure 2

Experimental sessions for the control and the moveable platform training groups

Figure 3

Experimental protocol for moveable platform training consisting of 24 trials of blocked slipand no slip trials (12), and randomized slip and no slip trials (12).

Figure 4

Changes in slip severity measures from Slip1 to Slip2 between control and moveable platform training group. Note. Statistics were performed on the difference values (Slip2 – Slip1). *p < 0.05, **p < 0.01.

Figure 5

Slip events of the perturbed (PerSide) foot and the unperturbed (UnSide) foot during Slip2 trial for training and control group. The graph only contains data from successful recovery. (TO- unperturbed foot toe off, PerHC- heel contact of the slipping foot).

Figure 6

Mean ± 1 SD of peak ankle and knee coactivity from T1- T12 slip training trials (training group), and from Slip1 and Slip2 trials (control and training group).

Figure 7

Mean ± 1 SD of center-of-mass velocity and transitional acceleration of whole body COM (TA) at heel contact from T1- T12 slip training trials (training group), and from Slip1 and Slip2 trials(control and training group).