Elsevier

Manual Therapy

Volume 13, Issue 4, August 2008, Pages 300-306
Manual Therapy

Original article
Lower lumbar spine axial rotation is reduced in end-range sagittal postures when compared to a neutral spine posture

https://doi.org/10.1016/j.math.2007.01.016Get rights and content

Abstract

Sports such as rowing, gymnastics, cycling and fast bowling in cricket that combine rotation with spine flexion and extension are known to carry greater risk of low back pain (LBP). Few studies have investigated the capacity of the lumbar spine to rotate in various sagittal positions, and further, these studies have generated disparate conclusions. The purpose of this study was to determine whether the range of lower lumbar axial rotation (L3–S2) is decreased in end-range flexion and extension postures when compared to the neutral spine posture. Eighteen adolescent female rowers (mean age=14.9 years) with no history of LBP were recruited for this study. Lower lumbar axial rotation was measured by an electromagnetic tracking system (3-Space Fastrak™) in end-range flexion, extension and neutral postures, in sitting and standing positions. There was a reduction in the range of lower lumbar axial rotation in both end-range extension and flexion (p<0.001) postures when compared to neutral. Further, the range of lower lumbar axial rotation measurements in flexion when sitting was reduced when compared to standing (p=0.013). These findings are likely due to the anatomical limitations of the passive structures in end-range sagittal postures.

Introduction

A number of studies have shown an increased prevalence of low back pain (LBP) (predominantly at the lower lumbar spine) amongst adolescent athletes in sports such as rowing, gymnastics, cycling and fast bowling in cricket. These sports involve high mechanical spinal loading in association with coupled flexion/extension and axial rotation of the lumbar spine and medium to high volumes of training and competition (Tertti et al., 1990; Burnett et al., 1996, Burnett et al., 2004; Balagué et al., 1999).

Recently, Perich et al. (2006) examined a large group of adolescent female rowers (N=356) and found the LBP point-prevalence to be 47.5%. In comparison an age, height, weight, socio-economic and physical activity matched non-rowing control group had LBP point-prevalence of 15.5%. In the rowers group, 64% of subjects reported that rowing in a sweep eight (rowing on one side of the body including spinal rotation) brought on or exacerbated their pain, whilst rowing in a single scull (14%) or quadruple scull (37%) (rowing on both sides of the body) pain was less common. Similarly, Burnett et al. (2004) reported that cyclists with chronic low back pain (chronic LBP) had a trend towards greater flexion/rotation of the lower lumbar spine during the crank cycle whilst riding seated on a wind trainer when compared to cyclists without LBP. At the other extreme, fast bowlers in cricket whose spines are exposed to high volumes of extension/side bending/rotational stress experience greater low back pain (LBP) and a higher risk of pathological spinal changes than non-bowlers (Burnett et al., 1996, Burnett et al., 1998; Ranson et al., 2005). These data are strongly suggestive of flexion or extension loading coupled with rotation and or side bending as a dominant factor in the aetiology and exacerbation of LBP in these specific populations.

It has been proposed that the risk of tissue strain is increased at end-range of spinal motion where the passive spinal structures are maximally loaded (Panjabi, 1992a, Panjabi, 1992b). The addition of rotation to a spinal segment that is already fully flexed or extended may result in increased tissue loading as passive spinal structures (bone, ligament and disc) may be limiting movement. In contrast, when the spine is loaded or rotated within a more neutral position of the motion segment, there may be more compliance within the passive spinal structures (Panjabi, 1992a, Panjabi, 1992b) therefore, reducing the risk of tissue strain. These considerations are consistent with the concept of neutral spine control, which is considered to be important in minimising spinal tissue strain.

Although spinal rotation represents a known risk factor for spinal injury, few studies have investigated the biomechanics of lumbar axial rotation in sagittal postures. Previous in vivo studies have reported reduced lumbar axial rotation in forward flexion when compared to upright sitting and standing (Gunzburg et al., 1991). Previous in vitro studies have reported reduced lumbar axial rotation in extension compared to neutral (Haberl et al., 2004) and a trend towards reduced axial rotation in flexion (Gunzburg et al., 1991; Haberl et al., 2004). In these studies it was not reported where in the sagittal plane (relative to end range), lumbar axial rotation was measured.

To our knowledge, no study has yet investigated the magnitude of lumbar axial rotation available in vivo, in neutral when compared to end-range flexed and extended postures. Mid-range and end-range flexed and extended postures are typical in sporting activities where LBP is common (Caldwell et al., 2003; Burnett et al., 2004; Perich et al., 2006; Ranson et al., 2005, Ranson et al., 2007). Therefore, the purpose of this study was to determine whether the range of lower lumbar axial rotation differed in end-range flexed and extended postures when compared to a neutral spine posture in sitting and standing positions. This research question was examined in a group of adolescent female rowers.

Section snippets

Subjects

This study utilised a cross-sectional repeated measures design, with 18 asymptomatic adolescent female rowers (mean±SD, age 14.9±0.9 years, mass 58.5±9.7 kg, height 1.69±0.08 m) recruited from a total population of approximately 400 female rowers from the Independent Girls Schools’ Sports Association in Western Australia. Potential subjects were initially identified by the Head of the Physical Education department in each participating school and those with no LBP were randomly selected and

Results

The single measure SEM values ranged between 0.7° and 2.4° and for each subject, the two trials for each condition were averaged. This approach was justified as the reliability for all variables describing the magnitude of axial rotation in all positions and postures was acceptable when considering the magnitude of the differences measured in the study (as detailed below). Further, there were no significant differences between the magnitude of left and right axial rotation in any of the

Discussion

Panjabi, 1992a, Panjabi, 1992b proposed the concept of the “neutral zone” where a region of high flexibility or relative laxity exists in neutral spine postures. In contrast, the “elastic zone” is defined as a region of high stiffness, where significant internal resistance to motion is provided. In flexion, this resistance is thought to be provided by the posterior fibres of the annulus and the posterior ligaments (Gunzburg et al., 1991, Gunzburg et al., 1992; Pearcy, 1993) whilst in extension

Conclusion

The results of this study demonstrate that reduced range of lower lumbar axial rotation exists in end-range flexion and extension postures when compared to a neutral spine posture, in both sitting and standing positions in a group of adolescent females. Further, there was a reduction of axial rotation in flexion when sitting was compared with standing. The reduction in axial rotation in end-range postures is likely to be due to the increased stiffness of the passive spinal structures in the

Acknowledgements

The authors thank, for their kind assistance throughout this study, Dr. Ritu Gupta for statistical advice and Ms. Debra Perich for liaising with the schoolgirl rowing program.

The authors declare the experiments of the study comply with the current laws of the country in which they were performed, with ethics approval obtained from the Institutional Human Research Ethics Committee and parents/guardians were required to provide their informed consent.

References (29)

  • G.G. Gregersen et al.

    An in vivo study of the axial rotation of the human thoracolumbar spine

    Journal of Bone and Joint Surgery

    (1967)
  • R. Gunzburg et al.

    Axial rotation of the lumbar spine and the effect of flexion; an in vitro and in vivo biomechanical study

    Spine

    (1991)
  • R. Gunzburg et al.

    Role of the capsulo-ligamentous structures in rotation and combined flexion-rotation of the lumbar spine

    Journal of Spinal Disorders

    (1992)
  • H. Haberl et al.

    Kinematic response of lumbar functional spinal units to axial torsion with and without superimposed compression and flexion/extension

    European Spine Journal

    (2004)
  • Cited by (40)

    • Lumbar axial rotation kinematics in men with non-specific chronic low back pain

      2019, Clinical Biomechanics
      Citation Excerpt :

      During data collection, each lumbar motion was standardized as follows: 1. Lumbar rotation in upright standing - the participant stood with his feet parallel, shoulder width apart, with his arms crossed and hands resting on his shoulders (Burnett et al., 2008) (Fig. 1). The participant was then asked to randomly rotate his shoulders to his preferred right or left side as far and as fast as possible without moving his feet.

    • Effect of static neck flexion in cervical flexion-relaxation phenomenon in healthy males and females

      2016, Journal of Bodywork and Movement Therapies
      Citation Excerpt :

      The variations in seated posture may result in differences in cervical spine posture (Black et al., 1996; Burnett et al., 2009), so subjects were asked to maintain their own neutral lumbar lordosis with an upright and neutral head posture. The neutral lordosis was considered as the mid-point between the end-range flexion and extension values (Burnett et al., 2008) and this was distinguished by experience physiotherapist. Therefore seated posture was standardized according to neutral lumbar lordosis.

    • Repeatability of kinematic and electromyographical measures during standing and trunk motion: How many trials are sufficient?

      2015, Journal of Electromyography and Kinesiology
      Citation Excerpt :

      The number of trials was selected based on a review of the literature. Typically, three trials or less have been used in previous literature (Burnett et al., 2008; Dankaerts et al., 2009; Edmondston et al., 2007a; Lariviere et al., 2000; Peach et al., 1998; Willems et al., 1996). While it may have been ideal to collect data for more than ten trials, the expectations for the time commitment of participants are limited to an extent (Sparto and Parnianpour, 2001).

    • Impact of lumbar spine posture on thoracic spine motion and muscle activation patterns

      2014, Human Movement Science
      Citation Excerpt :

      The reflective markers on the plates adhered to the spinous processes were used to define four rigid segments: upper-thoracic (T1–T4), mid-thoracic (T5–T8), lower-thoracic (T9–T12), and the lumbar segment (L1–PSISs) (Nairn et al., 2013). Electromyographical signals were collected bilaterally from eight muscles: external oblique (15 cm lateral to the umbilicus at a 45° angle (Marras & Mirka, 1993; McGill, 1991)); internal oblique (below external oblique and approximately midway between the anterior superior iliac spine and symphysis pubis, above the inguinal ligament (Cholewicki & McGill, 1996)); rectus abdominis (3 cm lateral to midline of abdomen, 2 cm above umbilicus (Drake, Fischer, Brown, & Callaghan, 2006; Marras & Mirka, 1993)); latissimus dorsi (most lateral portion of the muscle at the T9 level (Drake et al., 2006; McGill, 1991)); upper-thoracic erector spinae (ES) (largest muscle mass approximately 2.5 cm lateral to T4 spinous process (Burnett et al., 2008)); lower-thoracic ES (largest muscle mass approximately 4 cm lateral to T9 spinous process (Drake et al., 2006; McGill, 1991)); lumbar ES (largest muscle mass approximately 4 cm lateral to L3 spinous process (Drake et al., 2006; McGill, 1991)); and the superficial fibers of lumbar multifidus (multifidus: at L5 parallel to a line connecting the PSIS and L1–L2 interspinous space (Dankaerts, O’Sullivan, Burnett, & Straker, 2006)). The signals were differentially amplified (frequency response 10–1000 Hz, common mode rejection 115 dB at 60 Hz, input impedance 10 GΩ; two of model AMT-8, Bortec, Calgary, Canada), and converted from an analog to digital signal at a rate of 2400 Hz (Vicon MX motion capture system, Vicon Systems Ltd., Oxford, UK).

    View all citing articles on Scopus
    View full text