The Mechanism and Function of Lumbosacral Orthoses

描述（由申请人提供）：本研究通过测试四种假设，探讨腰骶矫形器（LSOs）在治疗下腰痛（LBP）中的新机制和功能。这些假设是基于lso增强脊柱稳定性的基本原理，在此背景下尚未考虑到这一点。LSO为腰椎提供了额外的稳定性，因此，LBP患者将(i)与“无LSO”相比，佩戴LSO时表现出较少的躯干对抗性肌肉共同收缩；（ii）与“无LSO”相比，佩戴LSO时躯干突然负荷的肌肉数量更少，潜伏期更长；（iii）与不佩戴LSO相比，佩戴LSO时走路的步态更接近正常模式。（iv）与没有佩戴LSO的情况相比，佩戴LSO时腰椎本体感觉增强。将从耶鲁大学脊柱服务诊所招募20名LBP受试者作为实验组和20名对照LBP受试者来检验每个假设。实验组受试者佩戴LSO 4-6周。所有受试者将每两周进行一次有和没有LSO的测试，在三个单独的实验中验证每个假设。这些实验将包括：(1)解决假设(i)和（ii）的肌电图实验，(2)解决假设（iii）的步态实验，以及(3)解决假设（iv）的本体感觉实验。

DESCRIPTION (provided by applicant): New mechanisms and function of lumbosacral orthoses (LSOs) in the management of low back pain (LBP) are explored in this application by testing four hypotheses. These hypotheses are based on the rationale of LSO-enhanced spine stability, which has not been considered in this context before. The LSO provides additional stability to the lumbar spine and, therefore, patients with LBP will (i) exhibit less trunk antagonistic muscle co-contraction when wearing the LSO as compared to the "No LSO" condition, (ii) respond with a smaller number of muscles and longer latency to sudden trunk loading when wearing the LSO as compared to the "No LSO" condition, (iii) walk with gait closer resembling a normal pattern when wearing the LSO as compared to walking without the LSO, and (iv) exhibit enhanced proprioception in the lumbar spine when wearing the LSO as compared to the "No LSO" condition. Twenty LBP subjects for the experimental group and 20 control LBP subjects will be recruited from the Yale Spine Service clinics to test each hypothesis. The subjects in the experimental group will wear the LSO for 4-6 weeks. All subjects will be tested every two weeks with and without the LSO in 3 separate experiments to address each hypothesis. These experiments will consist of (1) the EMG Experiment to address hypotheses (i) and (ii), (2) the Gait Experiment to address hypothesis (iii), and (3) the Proprioception Experiment to address hypothesis (iv). New research developments will allow us to overcome several methodological and conceptual difficulties to make the proposed research now feasible. Therefore, the application of the following features will distinguish the proposed research from past studies: (i) the concept and quantification of spine stability, (ii) an experimental design tuned to detect very small LSO effects in EMG activity, (iii) a novel, submaximal exertion procedure for normalizing EMG data for patients with LBP, who are reluctant or unable to exert maximum effort, and (iv) a long-term (4-6 weeks) study, which may be necessary for acclimatization to the LSO. The results from these studies could be used in formulating rational guidelines for the prescription of LSOs as well as for improving their designs. In addition, data generated from the proposed research will also carry-over into advancing our understanding of the mechanisms and function of ergonomic lumbar supports.