Abstract
Purpose
It has been shown that the conus medullaris displaces significantly and consistently in response to both unilateral and bilateral SLRs. Point of interest is represented by whether the magnitude of this displacement can be predicted in asymptomatic subjects. The purpose was to investigate whether any correlations existed between demographic and anthropometric factors and hip flexion angle with magnitude of conus medullaris displacement with the unilateral and bilateral SLR. This was done following the notion that there is the possibility that cord movement may contain aspects of predictability in asymptomatic subjects.
Methods
Using the same methods as in our previous MRI studies, we further investigated whether any correlations existed between age, height, weight, BMI or hip flexion angle and magnitude of conus medullaris displacement with the unilateral and bilateral SLR.
Results
Moderate to strong positive correlation was found between degree of hip flexion and magnitude of conus medullaris caudal displacement with unilateral and bilateral SLRs and CuMeD. A negligible inverse correlation between subjects’ height and magnitude of conus medullaris displacement in response to unilateral SLR was found, while no correlation (r < 0.1) emerged with bilateral SLR and CuMeD. No correlation was found for other values such as age, weight or BMI.
Conclusions
The data show that in in vivo and structurally intact asymptomatic volunteers, the degree of hip flexion may have strong predictive values for magnitude of neural displacement in response to unilateral and bilateral SLRs. This provides further justification to its quantification in clinical settings. Magnitude of conus medullaris displacement in response to unilateral and bilateral SLRs is not likely to be predicted from easily clinically collectable measures such as age, height, weight and BMI. This study offers information relevant to investigation of prediction of neuromechanical responses in neurodynamic tests.
Similar content being viewed by others
References
Charnley J (1951) Orthopaedic sign in the diagnosis of disc protrusion: with special reference to the straight-leg-raising test. Lancet 27:186–192
Smith SA, Massie JB, Chesnut R, Garfin SR (1993) Straight leg raising: anatomical effects on the spinal nerve root without and with fusion. Spine 18(8):992–999
Jonsson B, Stromqvist B (1995) The straight leg raising test and the severity of symptoms in lumbar disc herniation: a preoperative and postoperative evaluation. Spine 20(1):27–30
Inman VT, Saunders JB (1942) The clinico-anatomical aspects of the lumbosacral region. Radiology 38:669–678
Falconer MA, McGeorge M, Begg AC (1948) Observations of the cause and mechanism of symptom production in sciatica and low back pain. J Neurol Neurosurg Psychiatry 11:12–26
Goddard MD, Reid JD (1965) Movements induced by straight leg raising in the lumbosacral region. J Neurol Neurosurg Psychiatry 28:12–18
Breig A, Troup JDG (1979) Biomechanical considerations in the straight-leg-raising test. Cadaveric and clinical studies of the effects of medial hip rotation. Spine 4(3):242–250
Gilbert KK, Brismée JM, Collins DL et al (2007) 2006 young investigator award winner: lumbosacral nerve root displacement and strain: part 1. A novel measurement technique during straight leg raise in unembalmed cadavers. Spine 32(14):1513–1520
Gilbert KK, Brismée JM, Collins DL et al (2007) 2006 young investigator award winner: lumbosacral nerve root displacement and strain: part 2. A comparison of 2 straight leg raise conditions in unembalmed cadavers. Spine 32(14):1521–1525
Kobayashi S, Shizu N, Suzuki Y, Asai T, Yoshizawa H (2003) Changes in nerve root motion and intraradicular blood flow during an intraoperative straight-leg-raising test. Spine 28(13):1427–1434
Kobayashi S, Takeno K, Yayama T et al (2010) Pathomechanisms of sciatica in lumbar disc herniation: effect of periradicular adhesive tissue on electrophysiological values by an intraoperative straight leg raising test. Spine 35(22):2004–2014
Rade M, Könönen M, Vanninen R et al (2014) In vivo magnetic resonance imaging measurement of spinal cord displacement in the thoracolumbar region of asymptomatic subjects: part 1: straight leg raise test. Spine 39(16):1288–1293
Rade M, Könönen M, Vanninen R et al (2014) In vivo magnetic resonance imaging measurement of spinal cord displacement in the thoracolumbar region of asymptomatic subjects: part 2: comparison between unilateral and bilateral straight leg raise tests. Spine 39(16):1294–1300
Porter RW, Trailescu IF (1990) Diurnal changes in straight leg raising. Spine 15(2):103–106
Conflict of interest
We wish to confirm that there are no known conflicts of interest associated with this publication and there has been no significant financial support for this work that could have influenced its outcome. More specifically, we did not receive funding for this work from any of the following organizations: National Institutes of Health (NIH); Wellcome Trust; Howard Hughes Medical Institute (HHMI); and others.
Ethical standard
We further confirm that any aspect of the work covered in this manuscript that has involved human patients has been conducted with the ethical approval of the Research Ethical Committee of Kuopio University Hospital, approval number 79/2012, and that such approvals are acknowledged within the manuscript.
Author information
Authors and Affiliations
Corresponding author
Additional information
We, the authors, confirm that we have given due consideration to the protection of intellectual property associated with this work and that there are no impediments to publication, including the timing of publication, with respect to intellectual property. In doing so, we confirm that we have followed the regulations of our institutions concerning intellectual property.
Rights and permissions
About this article
Cite this article
Rade, M., Könönen, M., Marttila, J. et al. Correlation analysis of demographic and anthropometric factors, hip flexion angle and conus medullaris displacement with unilateral and bilateral straight leg raise. Eur Spine J 25, 724–731 (2016). https://doi.org/10.1007/s00586-015-3861-x
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00586-015-3861-x