Spinal posture is the position of the spine in the human body. It is debated what the optimal spinal posture is,[1] and whether poor spinal posture causes lower back pain.[2] Good spinal posture may help develop balance, strength and flexibility.[3][4]
Neutral spine
editLooking directly at the front or back of the body, the 33 vertebrae in the spinal column should appear completely vertical. From a side view, the cervical (neck) region of the spine (C1–C7) is bent inward, the thoracic (upper back) region (T1–T12) bends outward, and the lumbar (lower back) region (L1–L5) bends inward. The sacrum (tailbone area) (S1–S5 fused) and coccyx (on average 4 fused) rest between the pelvic bones.[5] A neutral pelvis is in fact slightly anteriorly rotated which means the anterior superior iliac spines should be just in front of the pubic symphysis not in the same vertical line.[6]
Posture abnormalities
editIn medicine and occupations concerned with physical fitness, the concept of good posture is referred to as "neutral spine".[7] In this context, proper posture or "neutral spine", is the proper alignment of the body between postural extremes. Deviations from neutral alignment are identified as excessive curvature or reduction in curvature. Rarely do these deviations in curvature occur in only one plane; however, they are typically referred to in this manner.[8] In the anterior/posterior view, deviation from vertical results in abnormal lateral curvature of the spine called scoliosis. In the sagittal view, excessive curvature in the cervical region is cervical lordosis, in the thoracic region thoracic kyphosis, and in the lumbar region lumbar lordosis. Reduction in curvature is typically termed flat back if present in the thoracic region and lumbar kyphosis if present in the lumbar region.[5] In posture analysis, the spine is compared to a plumb line to detect the aforementioned abnormalities. From the anterior/posterior view this plumb line should run vertically down the midline of the body dividing it symmetrically into right and left halves indicating even weight distribution on left and right sides. From the sagittal view the plumb line should bisect the ear, odontoid process of C2, the cervical vertebral bodies, the center of the glenohumeral joint, the lumbar vertebral bodies, the center of the acetabulum, just posterior to the patella, and through the tarsals of the feet.[9] This sagittal line of reference theoretically indicates even distribution of weight between the front and the back of the body.
Quantifying abnormalities
editScoliosis is well established and even evaluated at an early age. It is typically quantified using the standardized Cobb angle method. This method consists of measuring the degree of deformity by the angle between two successive vertebrae. The Cobb method was accepted by the Scoliosis Research Society (SRS) in 1966. It serves as the standard method for quantification of scoliosis deformities.[8] Sagittal plane posture aberrations such as cervical and lumbar lordosis and thoracic kyphosis have yet to be quantified due to considerable inter-individual variability in normal sagittal curvature.[10] The Cobb method was also one of the first techniques used to quantify sagittal deformity. As a 2D measurement technique it has limitations and new techniques are being proposed for measurement of these curvatures.[8] Most recently, 3D imaging techniques using computed tomography (CT) and magnetic resonance (MR) have been attempted. These techniques are promising but lack the reliability and validity necessary to be used as a reference for clinical purposes.[8]
References
edit- ^ O'Sullivan, Kieran; O'Sullivan, Peter; O'Sullivan, Leonard; Dankaerts, Wim (2012). "What do physiotherapists consider to be the best sitting spinal posture?". Manual Therapy. 17 (5): 432–437. doi:10.1016/j.math.2012.04.007. PMID 22608170.
- ^ Swain, Christopher T.V.; Pan, Fumin; Owen, Patrick J.; Schmidt, Hendrik; Belavy, Daniel L. (2020). "No consensus on causality of spine postures or physical exposure and low back pain: A systematic review of systematic reviews". Journal of Biomechanics. 102: 109312. doi:10.1016/j.jbiomech.2019.08.006. PMID 31451200. S2CID 201756091.
- ^ "How to Correct Posture Exercises - Sydney Sports and Exercise Physiology". ssep.com.au. 2020-07-11. Retrieved 2024-02-06.
- ^ https://studenthealth.sa.ucsb.edu/sites/default/files/2021-03/posture.pdf [bare URL PDF]
- ^ a b Marieb, E. N. (2001), Human Anatomy & Physiology, San Francisco, CA: Pearson Education Inc., Publishing as Benjamin Cummings, pp. 215–216
- ^ Kendal, F. P.; McCreary, E. K.; Provance, P. G.; Rodgers, M. M.; Romani, W A. (2005), Muscles Testing and Function with Posture and Pain (5th Edition), Baltimore, MD: Lippincott Williams & Wilkins, pp. 49–65
- ^ Webster, Deborah, The Neutral Spine, wellbridge.com, archived from the original on 2007-08-22
- ^ a b c d Vrtovec, T.; Pernus, F.; Likar, B. (2009), "A review of methods for quantitative evaluation of spinal curvature.", European Spine Journal, 18 (5): 593–605, doi:10.1007/s00586-009-0913-0, PMC 3233998, PMID 19247697
- ^ Kritz, E. N.; Croin (2008), Static Posture Assessment Screen of Athletes: Benefits and Considerations., Journal of Strength and Conditioning, pp. 18–27
- ^ Roussouly, P.; Gollogly, S.; Berthonnaud, E.; Dimnet, J. (2005), "Classification of the Normal Variation in the Sagittal Alignment of the Human Lumbar Spine and Pelvis in the Standing Position", Spine, 30 (3): 346–353, doi:10.1097/01.brs.0000152379.54463.65, PMID 15682018, S2CID 20997025