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Slump Test: Effect of Contralateral Knee Extension on Response Sensations in Asymptomatic Subjects and Cadaver Study
Michael Shacklock1, Brian Yee, Tom Van Hoof
1*Department of Physical and Rehabilitation Medicine, Kuopio University Hospital, Kuopio, Finland†Mercer University Physical Therapy Program, Atlanta, Georgia‡Ghent University, Ghent, Belgium§Amedisys Home Healthcare, Duluth, Georgia¶Gentiva Health Services, Seattle, Washington||Restore Health Group, Rosewell, Georgia**Neurodynamic Solutions, Adelaide, South Australia, Australia††Josip Juraj Strossmayer University of Osijek, Faculty of Medicine, Orthopaedic and Rehabilitation Hospital "Prim. dr.Martin Horvat", Rovinj, Croatia‡‡Department of Physical and Rehabilitation Medicine, Tampere University Hospital, Tampere, Finland§§Department of Orthopaedic, Traumatology and Hand Surgery, Kuopio University Hospital, Kuopio, Finland.
Study Design:
Part 1: A randomized, single-blind study on the effect of contralateral knee extension on sensations produced by the slump test (ST) in asymptomatic subjects. Part 2: A cadaver study simulating the nerve root behavior of part 1.
Objective:
Part 1: Test if contralateral knee extension consistently reduces normal stretch sensations with the ST.Part 2: Ascertain in cadavers an explanation for the results.
Summary Of Background Data:
In asymptomatic subjects, contralateral knee extension reduces stretch sensations with the ST. In sciatica patients, contralateral SLR also can temporarily reduce sciatica. We studied this methodically in asymptomatic subjects before considering a clinical population.
Methods:
Part 1: Sixty-one asymptomatic subjects were tested in control (ST), sham, or intervention (contralateral ST) groups and their sensation response intensity compared.Part 2: Caudal tension was applied to the L5 nerve root of 3 cadavers and tension behavior of the contralateral neural tissue recorded visually.
Results:
Part 1: Reduction of stretch sensations occurred in the intervention group but not in control and sham groups (P ≤ 0.001).Part 2: Tension in the contralateral lumbar nerve roots and dura reduced in a manner consistent with the responses in the intervention (contralateral ST) group.
Conclusion:
Part 1: In asymptomatic subjects, normal thigh stretch sensations with the ST reduced consistently with the contralateral ST, showing that this is normal and may now be compared with patients with sciatica.Part 2: Contralateral reduction in lumbar neural tension with unilateral application of tension-producing movements also occurred in cadavers, supporting the proposed explanatory hypothesis.
