Postural Responses to a Suddenly Released Pulling Force in Older Adults with Chronic Low Back Pain: An Experimental Study.
Chronic low back pain (CLBP), one of the most common musculoskeletal conditions in older adults, might affect balance and functional independence. The purpose of this study was to investigate the postural responses to a suddenly released pulling force in older adults with and without CLBP. Thirty community-dwelling older adults with CLBP and 26 voluntary controls without CLBP were enrolled. Participants were required to stand on a force platform while, with one hand, they pulled a string that was fastened at the other end to a 2-kg or to a 4-kg force in the opposite direction at a random order. The number of times the participants lost their balance and motions of center of pressure (COP) when the string was suddenly released were recorded. The results demonstrated that although the loss of balance rates for each pulling force condition did not differ between groups, older adults with CLBP had poorer postural responses: delayed reaction, larger displacement, higher velocity, longer path length, and greater COP sway area compared to the older controls. Furthermore, both groups showed larger postural responses in the 4-kg pulling force condition. Although aging is generally believed to be associated with declining balance and postural control, these findings highlight the effect of CLBP on reactive balance when responding to an externally generated force in an older population. This study also suggests that, for older adults with CLBP, in addition to treating them for pain and disability, reactive balance evaluation and training, such as reaction and movement strategy training should be included in their interventions. Clinicians and older patients with CLBP need to be made aware of the significance of impaired reactive balance and the increased risk of falls when encountering unexpected perturbations.
Department of Physical Therapy, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
Pei-Yun
PY
Lee
Department of Physical Therapy, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
Sang-I
SI
Lin
Department of Physical Therapy, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
Yu-Ting
YT
Liao
Department of Orthopedic, Tainan Municipal An-Nan Hospital-China Medical University, Tainan, Taiwan.
Ruey-Mo
RM
Lin
Department of Orthopedic, National Cheng Kung University Hospital, Tainan, Taiwan.
Che-Chia
CC
Hsu
Department of Orthopedic, National Cheng Kung University Hospital, Tainan, Taiwan.
Kuo-Yuan
KY
Huang
Department of Physical Therapy, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
Yi-Ting
YT
Chen
Department of Physical Therapy, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
Yi-Ju
http://orcid.org/0000-0003-4082-2634
YJ
Tsai
D000368:Aged; D016022:Case-Control Studies; D059350:Chronic Pain / Q000503:physiopathology; D005260:Female; D018737:Hand Strength / Q000502:physiology; D006801:Humans; D017116:Low Back Pain / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D009068:Movement / Q000502:physiology; D004856:Postural Balance / Q000502:physiology*; D011930:Reaction Time; D013314:Stress, Mechanical