Browse > Article
http://dx.doi.org/10.12674/ptk.2014.21.1.037

Comparison of Buttock Pressure and Pelvic Tilting Angle During Typing in Subjects With and Without Unilateral Low Back Pain  

Hwang, Ui-Jae (Dept. of Physical Therapy, The Graduate School, Yonsei University)
Kim, Si-Hyun (Dept. of Physical Therapy, The Graduate School, Yonsei University)
Choi, Houng-Sik (Dept. of Physical Therapy, Division of Health Science, Hanseo University)
Kwon, Oh-Yun (Dept. of Physical Therapy, College of Health Science, Yonsei University)
Publication Information
Physical Therapy Korea / v.21, no.1, 2014 , pp. 37-46 More about this Journal
Abstract
Asymmetric sitting posture may cause asymmetric buttock pressure and unilateral low back pain (LBP). The purpose of this study was to compare the differences of buttock pressure between both sides, and pelvic angle (sagittal and coronal planes) during typing in a sitting position on a pressure mat (Baltube) in individuals with and without unilateral LBP. Ten subjects with unilateral LBP and ten subjects without unilateral LBP were recruited for this study. Buttock pressure was measured using a pressure mat and pelvic angles were measured using a palpation meter. The subjects performed typing in a sitting posture for 30 minutes. Pressure data were collected and averaged at initial term (from start to first minutes) and final term (last minutes of 30 minutes). Angles of pelvic tilting were measured after 30 minutes typing. Pressure asymmetry values (difference in pressure between both sides) were calculated at the initial and final terms. A two-way analysis of variance was used to compare the differences between the initial and final pressure asymmetry values in subjects with and without unilateral LBP. An independent t-test was applied to compare the pelvic tilt angles between the two groups. To compare the change of pressure from the initial term to the final term between the symptomatic and asymptomatic sides in the unilateral LBP group, a paired t-test was applied. In the unilateral LBP group, the pressure asymmetric value at the final term was significantly greater than that of the initial term (p<.05). The angle of pelvic tilting in coronal plane was significantly greater in the unilateral back pain group compared to the without unilateral LBP group (p<.05), however, there was no significant difference in the angle of pelvic tilting in the sagittal plane between the two groups (p>.05). In the unilateral LBP group, the change of pressure from the initial term to the final term was significantly less in the symptomatic side (-6.90 mmHg) than the asymptomatic side (5.10 mmHg). This asymmetric sitting posture may contribute to unilateral LBP in the sitting position. Further studies are needed to determine if asymmetric weight bearing in sitting causes unilateral LBP or if unilateral back pain causes asymmetric weight bearing, and if the correction of asymmetric weight bearing in sitting can reduce unilateral LBP.
Keywords
Buttock pressure; Pelvic tilting angle; Sitting posture; Typing; Unilateral low back pain;
Citations & Related Records
연도 인용수 순위
  • Reference
1 Williams MM, Hawley JA, Mckenzie RA et al. A comparison of the effects of two sitting postures on back and referred pain. Spine (Phila Pa 1976). 1991;16(10):1185-1191.   DOI
2 Womersley L, May S. Sitting posture of subjects with postural backache. J Manipulative Physiol Ther. 2006;29(3):213-218.   DOI   ScienceOn
3 Maughan EF, Lewis JS. Outcome measures in chronic low back pain. Eur Spine J. 2010;19(9): 1484-1494.   DOI
4 Nachemson A. Toward a better understanding of back pain: A review of the mechanics of the lumbar disc. Rheumatol Rehabil. 1975;14(3):129-143.   DOI
5 Marshall P, Murphy B. Delayed abdominal muscle onsets and self-report measures of pain and disability in chronic low back pain. J Electromyogr Kinesiol. 2010;20(5):833-839.   DOI   ScienceOn
6 Park SY, Yoo YG. Effects of a posture-sensing air seat device (PSASD) on kinematics and trunk muscle activity during continuous computer work. J Physiol Anthropol. 2011;30(4):147-151.   DOI
7 Riegger-Krugh C, Keysor JJ. Skeletal malalignments of the lower quarter: Correlated and compensatory motions and postures. J Orthop Sports Phys Ther. 1996;23(2):164-170.   DOI
8 Sauter SL, Schleifer LM, Knutson SJ. Work posture, workstation design, and musculoskeletal discomfort in a VDT data entry task. Hum Factors. 1991;33(2):151-167.   DOI
9 McCaw ST, Bates BT. Biomechanical implications of mild leg length inequality. Br J Sports Med. 1991;25(1):10-13.   DOI   ScienceOn
10 Sahrmann S. Diagnosis and Treatment of Movement Impairment Syndromes. 1st ed. St Louis, MO, Mosby, 2002:106-108.
11 Van Dieen, De Looze HP, Hermans V. Effects of dynamic office chairs on trunk kinematics, trunk extensor EMG and spinal shrinkage. Ergonomics. 2001;44(1):739-750.   DOI
12 Vergara M, Page A. Relationship between comfort and back posture and mobility in sitting-posture. Appl Ergon. 2002;33(1):1-8.   DOI   ScienceOn
13 Egan DA, Al-Eisa E. Pelvic skeletal asymmetry, postural control, and the association with low back pain: A review of the evidence. Crit Rev Phys Rehabil Med. 1999;11:299-338.
14 Watanabe S, Eguchi A, Kobara K, et al. Influence of trunk muscle co-contraction on spinal curvature during sitting for desk work. Electromyogr Clin Neurophysiol. 2007;47(6):273-278.
15 Gadge K, Innes E. An investigation into the immediate effects on comfort, productivity and posture of the bambach saddle seat and a standard office chair. Work. 2007;29(3):189-203.
16 Egan DA, Cole J, Twomey L. The standing forward flexion test: An inaccurate determinant of sacroiliac joint dysfunction. Physiotherapy. 1996; 82(4):236-242.   DOI   ScienceOn
17 Faul F, Erdfelder E, Lang AG, et al. G*power 3: A flexible statistical power analysis program for the social, behavioral, and biomedical sciences. Behav Res Methods. 2007;39(2):175-191.   DOI   ScienceOn
18 Dankaerts W, O'Sullivan P, Burnett A, et al. Differences in sitting postures are associated with non specific chronic low back pain disorders when sub classified. Spine (Phila Pa 1976). 2006;31(6):698-704.   DOI   ScienceOn
19 Grundy PF, Roberts CJ. Does unequal leg length cause back pain? A case-control study Lancet. 1984;2(8397):256-258.
20 Hagins M, Brown M, Cook C, et al. Intratester and intertester reliability of the palpation meter (palm) in measuring pelvic position. J Man Manip Ther. 1998;6(3):130-136.   DOI   ScienceOn
21 Knutson GA. Incidence of foot rotation, pelvic crest unleveling, and supine leg length alignment asymmetry and their relationship to self-reported back pain. J Manipulative Physiol Ther. 2002;25 (2):110E.
22 Al-Eisa E, Egan D, Wassersug R. Fluctuating asymmetry and low back pain. Evol Hum Behav. 2004;25(1):31-37.   DOI
23 Lee JH, Yoo WG. Changes in gluteal pressure and pelvic inclination angles after continuous cross-legged sitting. Work. 2011;40(2):247-252.
24 Aaras A, Fostervold KI, Ro O, et al. Postural load during VDU work: A comparison between various work postures. Ergonomics. 1997;40(II): 1255-1268.   DOI   ScienceOn
25 Al-Eisa E, Egan D, Deluzio K, et al. Effects of pelvic skeletal asymmetry on trunk movement: Three dimensional analysis in healthy individuals versus patients with mechanical low back pain. Spine (Phila Pa 1976). 2006;31(3): E71-E79.   DOI
26 Beneck GJ, Kulig K. Multifidus atrophy is localized and bilateral in active persons with chronic unilateral low back pain. Arch Phys Med Rehabil. 2012;93(2):300-306.   DOI