With some back conditions, specific positions can change the symptoms. These positions are known as biases and they includeflexionand extension.
These biases are also called direction preferences. If your back feels better and/or your symptoms abate when you bend forward, for example, it’s likely that the injury or condition you experience has a flexion bias.
A bias occurs due to the movement of tissue in the joint. With certain position changes, the relationship of space, muscles, tendons, ligaments, cartilage, and bones changes slightly within and around a joint, worsening or relieving painful pressure and compression. And defects in tissues—such as bone spurs or out-of-place structures—will move slightly with position changes as well.
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How Does Flexion Affect Back Pain?
Spinal stenosis, which is a condition that narrows the space in the intervertebral foramen, generally has a flexion bias.Many people who have pain due to spinal stenosis find that bending their spine forward (aka spinal flexion) makes it feel better.
Other conditions that usually have a flexion bias includespondylosisandspondylolisthesis.For injuries and conditions with a flexion bias, symptoms tend to increase when your back is extended (arched).
Extension Bias
The opposite of flexion bias isextension bias. As you can probably guess, an extension bias occurs when the movement of arching your back makes your symptoms feel better.
Examples of conditions that tend to have extension biases are herniated and bulging disc.People who have either of these conditions often find that when they bend forward (into spinal flexion) their symptoms worsen, and when they arch their back, it feels better.
Directional Preferences Help Classify Your Low Back Pain
The non-pathoanatomical system takes its cue (for evaluation and treatment choices) from the symptoms you report and what your therapist observes in your movements. This system is used in theMcKenzie methodand other physical therapy treatment methods.
The pathoanatomical approach to classifying low back pain is based on identifying structural changes and their effects through a physical examination, which includes aneurological examination. Defects in movement, sensation, and reflexes are used to help identify the cause of back pain. And diagnostic tests can visualize structural changes, such as a herniated disc or a compressed nerve.
These two diagnostic systems are used together to help your medical team understand how structural changes in your back are affecting your pain and movements. And all of this is used to help design the best treatment plan for your back pain.
Spinal Flexion and Low Back Pain
6 Sources
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Dunsford A, Kumar S, Clarke S.Integrating evidence into practice: use of Mckenzie-based treatment for mechanical low back pain.J Multidiscip Healthc. 2011;4:393-402. doi:10.2147/JMDH.S24733.Bagley C, MacAllister M, Dosselman L, Moreno J, Aoun SG, El Ahmadieh TY.Current concepts and recent advances in understanding and managing lumbar spine stenosis.F1000Res. 2019;8:F1000 Faculty Rev-137. doi:10.12688/f1000research.16082.1Genevay S, Atlas SJ.Lumbar spinal stenosis.Best Pract Res Clin Rheumatol. 2010;24(2):253–265. doi:10.1016/j.berh.2009.11.001Ferrari S, Vanti C, O’Reilly C.Clinical presentation and physiotherapy treatment of 4 patients with low back pain and isthmic spondylolisthesis.J Chiropr Med. 2012;11(2):94–103. doi:10.1016/j.jcm.2011.11.001Oakley PA, Harrison DE.Lumbar extension traction alleviates symptoms and facilitates healing of disc herniation/sequestration in 6-weeks, following failed treatment from three previous chiropractors: a CBP® case report with an 8 year follow-up.J Phys Ther Sci. 2017;29(11):2051–2057. doi:10.1589/jpts.29.2051Petersen T, Laslett M, Juhl C.Clinical classification in low back pain: best-evidence diagnostic rules based on systematic reviews.BMC Musculoskelet Disord. 2017;18(1):188. doi:10.1186/s12891-017-1549-6
Dunsford A, Kumar S, Clarke S.Integrating evidence into practice: use of Mckenzie-based treatment for mechanical low back pain.J Multidiscip Healthc. 2011;4:393-402. doi:10.2147/JMDH.S24733.
Bagley C, MacAllister M, Dosselman L, Moreno J, Aoun SG, El Ahmadieh TY.Current concepts and recent advances in understanding and managing lumbar spine stenosis.F1000Res. 2019;8:F1000 Faculty Rev-137. doi:10.12688/f1000research.16082.1
Genevay S, Atlas SJ.Lumbar spinal stenosis.Best Pract Res Clin Rheumatol. 2010;24(2):253–265. doi:10.1016/j.berh.2009.11.001
Ferrari S, Vanti C, O’Reilly C.Clinical presentation and physiotherapy treatment of 4 patients with low back pain and isthmic spondylolisthesis.J Chiropr Med. 2012;11(2):94–103. doi:10.1016/j.jcm.2011.11.001
Oakley PA, Harrison DE.Lumbar extension traction alleviates symptoms and facilitates healing of disc herniation/sequestration in 6-weeks, following failed treatment from three previous chiropractors: a CBP® case report with an 8 year follow-up.J Phys Ther Sci. 2017;29(11):2051–2057. doi:10.1589/jpts.29.2051
Petersen T, Laslett M, Juhl C.Clinical classification in low back pain: best-evidence diagnostic rules based on systematic reviews.BMC Musculoskelet Disord. 2017;18(1):188. doi:10.1186/s12891-017-1549-6
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