Forward Head Posture Found to be a Primary Cause of Altered Sensori-Motor Control and Excitability of the Autonomic Nervous System
By: Deed E. Harrison, DC
Recently, the CBP NonProfit and Cairo University research team published in the Journal Gait and Posture. Their article was entitled: “Is forward head posture relevant to autonomic nervous system function and cervical sensorimotor control? Cross sectional study” and authored by Professor Ibrahim M. Moustafa and colleagues.1 Importantly, this is really a break-through investigation documenting that forward head posture (FHP) is a strong driver of altered-abnormal sensori-motor control and increased amplitude (strength-activity) in the autonomic nervous system (ANS).
In its essence, sensori-motor control is the ability of the brain and nervous system to process different sources of external stimuli (sight, sound, touch, taste, smell) and rapidly transform this sensori input into an output of muscle or motor activity. For example, if you were in the mountains hiking a back country trail and a loud, strange animal sound is heard to your right, your brain immediately processes this into a multitude of actions-reactions such as turning your body or neck sharply towards the direction of the noise and getting ready for a possible fight or flight response. To this end, the sensori-motor system has evolved over millennia and is constantly learning, developing, and adapting to the tasks that an individual performs both physically and cognitively.
Causes of Altered Sensor-Motor Control
The sensori-motor system involves complex interactions between the brain and visual, auditory, muscular, ligamentous, and skin receptors. Because the sensori-motor system is constantly evolving for good or bad in each person, it is important to engage in activities that promote an efficient system. Small and large motor tasks involving hand eye-coordination activities, balance activities, regular functional fitness, etc. are all important as part of a weekly regimen to increase the efficiency of the functionality of the sensori-motor system. Problematically, injuries to the individual components of the sensori-motor system can cause a cascading effect where the entire system can go awry. For example, inner ear infections can cause serious balance and posture control problems in people leading to abnormal walking, dizziness, and nausea to name a few.
Regarding the spine, it is known that injuries to the joints, ligaments, discs, and muscles of the spine will cause abnormalities of the sensori-motor control system. Thus, motor vehicle crashes, falls injuring the head, neck and spine joints may potentially create detrimental long-term problems with sensori-motor control. Joint range of motion, muscle strength and endurance are also known to have influences on the sensori-motor system. However, until recently, the effect of abnormal posture alignment on the sensori-motor system has not been precisely documented.
Figure 1. Forward Head Posture Measurement using PostureScreen. Image ©Copyright CBP Seminars. Reprinted with Permission. All rights reserved.
New Break Through Randomized Trial
Recently a breakthrough case control trial was conducted at Cairo University in Egypt and co-authored by CBP NonProfit President Dr. Deed Harrison, DC. The Cairo University team was led by Professor Ibrahim Moustafa, PT, PhD.
Clinical features: The study investigated 160 participants aged between 20-35 years. The participants were matched for important
- clinical and physical characteristics and all of them were asymptomatic, without neck pain, headaches, etc. The participants were divided into those with forward head posture and those without forward head posture. Figure 1 depicts forward head posture and shows the measurement used in the study. When forward head posture increases in a person, angle A (figure 1) becomes increasingly smaller, oppositely, when head posture becomes more normal, angle A increases. The cut point for normal head posture in studies is 55 degrees and larger.2 In the new, current trial, Moustafa et al1 used less than 50 degrees for abnormal forward head posture and above 55 degrees for normal aligned head posture.
Assessments: There are a variety of methods to assess the function and efficiency of the sensori-motor control system. Moustafa and colleagues1 chose to use 4 primary assessments including:
- a measurement of the ability to reposition joints in a certain movement and neutral posture termed head repositioning accuracy,
- the ability to control the center of gravity of the body on a balance stability dynamic platform,
- a measurement of the efficiency of the eyes and the cervical spine to control and coordinate movement called the smooth pursuit neck torsion test,
- and they included an assessment of the efficiency of the autonomic nervous system looking at the speed and strength of the sympathetic skin resistance response.
Important Findings and Conclusion: The study findings are very important in the assessment of and treatment of patients with cervical spine and task performance problems. Reading the study, it becomes apparent that abnormal head and neck alignment are at the root cause of many neuro-musculo-skeletal disorders. Specifically, the study by Moustafa and colleagues1 identified the following main features:
- Forward head posture negatively affects cervical sensorimotor control.
- Forward head posture negatively affects the autonomic nervous system.
- There is strong correlation between the CVA (forward head posture) and cervical sensorimotor outcomes.
- There is strong correlation between the CVA (forward head posture) and skin sympathetic outcomes.
How Can You Get Help for Altered Posture, Altered Sensori-motor control, and Other Health Disorders?
Chiropractic BioPhysics® (CBP®) trained corrective care Chiropractic Physicians are located throughout the United States and in several international locations. CBP Technique clinicians have helped thousands of people throughout the world realign their posture and cervical spines back to health, and eliminate a potential source of altered movement, balance, dizziness, chronic neck pain, chronic headaches, general pain syndromes, and a wide range of other health conditions. If you are serious about your health and the health of your loved ones, contact a CBP trained provider today to see if you qualify for care. See www.CBPpatient.com for providers in your area.
- Moustafa IM, Youssef A, Ahbouch A, Tamim M, Harrison DE. Is forward head posture relevant to autonomic nervous system function and cervical sensorimotor control? Cross sectional study. Gait and Posture 2020; 77: 29-35.
- C.H.T. Yip, T.T.W. Chiu, A.T.K. Poon, The relationship between head posture and severity and disability of patients with neck pain, Man. Ther. 13 (2008) 148–154, https://doi.org/10.1016/j.math.2006.11.002.