Lara Allet1, Hogene Kim2, James Ashton-Miller3, Trina De Mott4, James K Richardson4. 1. Department of Physiotherapy, University of Applied Sciences of Western Switzerland, Geneva, Switzerland; Department of Physical Medicine & Rehabilitation, University of Michigan, Ann Arbor, MI, USA; Health Care Directorate, University Hospitals and University of Geneva, Geneva, Switzerland. Electronic address: lara.allet@hesge.ch. 2. Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA. 3. Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA; Department of Mechanical Engineering, Biomechanics Research Laboratory, University of Michigan, Ann Arbor, MI, USA. 4. Department of Physical Medicine & Rehabilitation, University of Michigan, Ann Arbor, MI, USA.
Abstract
AIMS: Distal symmetric polyneuropathy increases fall risk due to inability to cope with perturbations. We aimed to 1) identify the frontal plane lower limb sensorimotor functions which are necessary for robustness to a discrete, underfoot perturbation during gait; and 2) determine whether changes in the post-perturbed step parameters could distinguish between fallers and non fallers. METHODS:Forty-two subjects (16 healthy old and 26 with diabetic PN) participated. Frontal plane lower limb sensorimotor functions were determined using established laboratory-based techniques. The subjects' most extreme alterations in step width or step length in response to a perturbation were measured. In addition, falls and fall-related injuries were prospectively recorded. RESULTS: Ankle proprioceptive threshold (APrT; p=.025) and hip abduction rate of torque generation (RTG; p=.041) independently predicted extreme step length after medial perturbation, with precise APrT and greater hip RTG allowing maintenance of step length. Injured subjects demonstrated greater extreme step length changes after medial perturbation than non-injured subjects (percent change = 18.5 ± 9.2 vs. 11.3 ± 4.57; p = .01). CONCLUSIONS: The ability to rapidly generate frontal plane hip strength and/or precisely perceive motion at the ankle is needed to maintain a normal step length after perturbation, a parameter which distinguishes between subjects sustaining a fall-related injury and those who did not.
RCT Entities:
AIMS: Distal symmetric polyneuropathy increases fall risk due to inability to cope with perturbations. We aimed to 1) identify the frontal plane lower limb sensorimotor functions which are necessary for robustness to a discrete, underfoot perturbation during gait; and 2) determine whether changes in the post-perturbed step parameters could distinguish between fallers and non fallers. METHODS: Forty-two subjects (16 healthy old and 26 with diabetic PN) participated. Frontal plane lower limb sensorimotor functions were determined using established laboratory-based techniques. The subjects' most extreme alterations in step width or step length in response to a perturbation were measured. In addition, falls and fall-related injuries were prospectively recorded. RESULTS: Ankle proprioceptive threshold (APrT; p=.025) and hip abduction rate of torque generation (RTG; p=.041) independently predicted extreme step length after medial perturbation, with precise APrT and greater hip RTG allowing maintenance of step length. Injured subjects demonstrated greater extreme step length changes after medial perturbation than non-injured subjects (percent change = 18.5 ± 9.2 vs. 11.3 ± 4.57; p = .01). CONCLUSIONS: The ability to rapidly generate frontal plane hip strength and/or precisely perceive motion at the ankle is needed to maintain a normal step length after perturbation, a parameter which distinguishes between subjects sustaining a fall-related injury and those who did not.
Authors: John D England; Gary S Gronseth; Gary Franklin; Robert G Miller; Arthur K Asbury; Gregory T Carter; Jeffrey A Cohen; Morris A Fisher; James F Howard; Laurence J Kinsella; Norman Latov; Richard A Lewis; Phillip A Low; Austin J Sumner Journal: Arch Phys Med Rehabil Date: 2005-01 Impact factor: 3.966
Authors: K M Venkat Narayan; James P Boyle; Theodore J Thompson; Stephen W Sorensen; David F Williamson Journal: JAMA Date: 2003-10-08 Impact factor: 56.272
Authors: James K Richardson; James T Eckner; Lara Allet; Hogene Kim; James A Ashton-Miller Journal: Am J Phys Med Rehabil Date: 2017-01 Impact factor: 2.159