J Manipulative Physiol Ther. 2015 (Mar); 38 (3): 167–178 ~ FULL TEXT
Ibrahim M. Moustafa, PT, PhD, Aliaa A. Diab, PT, PhD
Basic Science Department,
Faculty of Physical Therapy,
Cairo University, Giza, Egypt.
Objective The purpose of this study was to determine the immediate and long-term effects of a multimodal program, with the addition of forward head posture correction, in patients with chronic discogenic lumbosacral radiculopathy.
Methods This randomized clinical study included 154 adult patients (54 females) who experienced chronic discogenic lumbosacral radiculopathy and had forward head posture. One group received a functional restoration program, and the experimental group received forward head posture corrective exercises. Primary outcomes were the Oswestry Disability Index (ODI). Secondary outcomes included the anterior head translation, lumbar lordosis, thoracic kyphosis, trunk inclination, lateral deviation, trunk imbalance, surface rotation, pelvic inclination, leg and back pain scores, and H-reflex latency and amplitude. Patients were assessed at 3 intervals (pretreatment, 10-week posttreatment, and 2-year follow-up).
Results A general linear model with repeated measures indicated a significant group × time effect in favor of the experimental group on the measures of ODI (F = 89.7; P < .0005), anterior head translation (F = 23.6; P < .0005), H-reflex amplitude (F = 151.4; P < .0005), H-reflex latency (F = 99.2; P < .0005), back pain (F = 140.8; P < .0005), and leg pain (F = 72; P < .0005). After 10 weeks, the results revealed an insignificant difference between the groups for ODI (P = .08), back pain (P = .29), leg pain (P = .019), H-reflex amplitude (P = .09), and H-reflex latency (P = .098). At the 2-year follow-up, there were significant differences between the groups for all variables adopted for this study (P < .05).
Conclusions The addition of forward head posture correction to a functional restoration program seemed to positively affect disability, 3-dimensional spinal posture parameters, back and leg pain, and S1 nerve root function of patients with chronic discogenic lumbosacral radiculopathy.
From the FULL TEXT Article:
Lumbosacral radiculopathy associated with disk herniation is one of the most common health-related complaints.  It is a disorder associated with delayed recovery, persistent disability, and increased health care utilization and costs.  Despite the high prevalence of this condition,  its conservative treatment has been a challenge  because there is no strong evidence for the effectiveness of most treatments, particularly in long-term management. 
The challenge that clinicians face results from focusing on pathoanatomy as one of the most common etiological factors of back pain, ignoring the significant role of dysfunction. It is important to address Murphy's concept,  which states that “pathoanatomy and dysfunction often interact to produce clinical symptoms.” In terms of biomechanical dysfunction, there is a growing interest in the quantification of abnormal asymmetrical posture. [7-11] Abnormal posture is one of the most important etiological factors associated with low back pain. [12, 13]
Studies have reported that many postural reflexes such as the vestibulocollic reflex, cervicocollic reflex, pelvo-ocular reflex, vestibuloocular reflex, cervico-ocular reflex, and cervical somatosensory input are located or occur in the head and neck region.  Given the high incidence of forward head posture, especially in older adults,  a correction of this abnormal posture must achieve optimal postural correction in which the spine orients itself according to the normalized reference point. 
One component lacking in nearly all forms of lumbar radiculopathy treatment is the effect of the cervical spine in determining spinal posture closely linked to low back pain. [12, 13] To the best of our knowledge, only 1 published randomized controlled trial has addressed head posture correction and its effect on spinal posture, and that study was limited to adolescent idiopathic scoliotic patients. 
Although the effect that forward head posture has on the entire nervous system has been reported, [17, 18] there are few controlled studies evaluating the effect of abnormal head posture on lumbar nerve root function. The current evidence to support the role of forward head posture correction in patients with lumbar disk herniation radiculopathy lacks the experimental data to support a cause-and-effect relationship and interventional outcomes. The purpose of this study was to evaluate the immediate and long-term effects of a multimodal program, with the addition of forward head posture correction, on disability, 3-dimensional spinal posture parameters, back and leg pain, and S1 nerve root function of patients with chronic discogenic lumbosacral radiculopathy.
Sample of radiographic findings at the 3 intervals of measurement.
This randomized controlled trial compared the outcomes of lumbosacral radiculopathy disability, pain, neurophysiological parameters, and 3-dimensional postural measures in a group receiving a forward head correction exercise program and a functional restoration program to a group receiving only a functional restoration program. The comparison between the experimental and standard care groups in the AHT and 3-dimensional posture parameters revealed significant differences at the 2 follow-up points. The results of the lumbar radiculopathy management outcomes such as disability, leg and back pain intensity, and neurophysiological parameters after 10 weeks indicate that the intervention programs succeed. At the 2-year follow-up, the statistically significant changes favoring the outcomes of the experimental group provide objective evidence that biomechanical dysfunction in terms of abnormal head posture and not lumbosacral pathoanatomy alone influences the long-term outcome measures of lumbosacral radiculopathy.
Although we could not find any literature data directly evaluating the effect of forward head posture correction and consequently restoring of normal global spinal posture in the management of lumbosacral radiculopathy, the current results agree on the concept of During et al,  who highlighted the role of abnormal posture in the generation of low back pain. This concept makes sense and agrees with Endo et al,  who stated that quantitative assessment of spinal alignment provides a better understanding of the pathophysiology of lumbar disk herniation. Overall, the role of posture correction in the management of back disorders is an interesting concept often highlighted in many articles. [12, 13, 22] However, this concept was not more than suggestions and recommendations points with no applied strategy.
In our study, we found that the experimental group that received forward head posture corrective exercises experienced significant changes in the posture parameters in the sagittal, transverse, and coronal planes. These significant changes may suggest that the cervical spine has an important role in global spinal posture.
The restoration of normal posture may be a direct consequence for restoring the normal afferentation process. It has been proposed that as the position of the head migrates forward or away from the body's vertical axis, increased strain is placed upon the muscles of the head, neck, and shoulders. This abnormal head posture results in joint dysfunctions that lead to abnormal afferent information (dysafferentation). [35, 36]
On theoretic grounds, it can be assumed that posture is largely maintained by reflexive, involuntary control. These reflexive components for postural control are found in skin and joint receptors, somatic graviceptors, and baroreceptors throughout the body. Because much of the reflexive postural control mechanisms are housed or occur within the head and neck region primarily,  disturbance of neurologic regulation of static upright human posture is possibly associated with forward head posture.
These results follow those reported by Diab,  who examined the role of head posture on the 3-dimensional spinal posture parameters and reported that “forward head correction was effective in improving the scoliotic posture in transverse, coronal, and sagittal planes.” These results are in agreement with neurophysiological studies that have identified a neurologic regulation of static upright human posture that is largely dependent on head posture [37, 38] and, consequently, the normal afferentation process.
Applying a functional restoration program alone or in conjunction with forward head posture corrective exercises appears to be approximately equal in successfully improving the disability, leg and back pain intensity, and neurophysiological findings after 10 weeks of treatment. At the 2-year follow-up, the results revealed statistically significant changes favoring the outcomes of the experimental group for the previous variables.
After 10 weeks of treatment, the marked improvement in symptoms and functional ability and resolving the neurophysiological findings are similar to those reported in a case study that showed the effectiveness of this type of exercise-based rehabilitation of patients with lumbar disk herniation radiculopathy.  Generally, evidence is moderate to strong that multidisciplinary rehabilitation reduces disability and pain in patients with chronic pain of the low back compared with usual care or nonmultidisciplinary treatment. [39, 40] Although there is significant variation in the precise content of different described functional restoration programs, they typically follow the identical principles of rehabilitation.
After 10 weeks of treatment, it was surprising that the addition of forward head posture correction to a functional restoration program did not produce a significantly (statistically) better effect than the functional restoration program across all outcomes given the preliminary evidence of significant role of normal posture in normalizing the afferentation process. There is no clear explanation for these findings, but we can speculate that a sustained postural imbalance can result in establishment of a state of continuous asymmetric loading. Once it is established and maintained beyond a critical threshold for weight and time, there will be increases in the degenerative changes in the muscles, ligaments, bony structures, and neural elements.  Most important, when the asymmetry is reversed and the unbalanced loading is thereby corrected by restoring normal posture, the reversible of these degenerative changes or even its improvement will need time. These interesting findings are in agreement with a previous study that reported decrease in pain intensity scale after 6-month follow-up compared to 10-week posttreatment.  Diab identified more decrease in functional index scale after 3-month follow-up compared to 10-week posttreatment. 
Although there were no statistically significant differences between groups with any of the lumbosacral management outcome measures (ODI, H-reflex parameters, and back and leg pain), the precision of the point estimates of the treatment effects must be considered. At the 10-week follow-up, the percentage of improvement was 11% for ODI. This value meets the threshold for meaningful clinically important change of the ODI (8-12 percentage points). Despite the minor improvement, we cannot confidently exclude a treatment effect for these variables at these time points. 
At the 2-year follow-up, the statistically significant changes favoring the outcomes of the experimental group for the previous variables may suggest an important role for head posture and, consequently, 3-dimensional global spinal posture. These changes exceed the threshold for meaningful clinically important change of the all variables adopted for this study. Thus, we cannot confidently exclude the clinical treatment effect for forward head posture correction at these specific time points. Specifically, although the functional restoration program highlighted the role of appropriate diagnosis and psychosocial and deconditioning factors in contrast to the traditional functional restoration approach, its diagnostic role was limited to the pathology of each patient, [42, 43] ignoring the role of biomechanical dysfunction as represented by forward head posture. This biomechanical dysfunction is thought to have physiological consequences with their effects on the inflow of sensory information to the central nervous system.
Harrison et al  have shown that abnormal cervical posture alters the mechanical properties of the spinal cord and nerve roots, which may change the firing patterns of the neurons that comprise these structures. It is clear that the somatosensory system of the neck may influence the motor control of the neck, eyes, limbs, and respiratory muscles and possibly the activity of some preganglionic sympathetic nerves. 
The continuous asymmetrical loading from biomechanical dysfunction represented by forward head and sagittal, transverse, and coronal abnormal spinal posture may explain the significant decline in all of the measured variables for the standard care group at the 2-year follow-up. This explanation is largely supported by Stemper et al,  who reported that abnormal spinal curvatures enhance the likelihood of whiplash injury and may have long-term clinical and biomechanical implications.
Similarly, Troyanovich et al  noted that correction of spinal posture might be related to the long-term health of the spine. Abnormal posture elicits abnormal stress and strain in many structures, including bones, intervertebral disks, facet joints, musculotendinous tissues, and neural elements that are considered predisposing factors for pain. These findings concurred with those of Dolphens et al,  who concluded that global spinal posture, especially of gross body segments, is required to achieve significant clinical improvement.
Another study showed that when posture abnormalities are more pronounced, compensatory strategies may no longer be effective, and disability may occur.  Recently, Kamitani et al have confirmed that the shape of a person's spinal column may predict their risk for disability in old age and thus their need for home assistance.  More specifically, upright posture is considered as a first-class lever mechanical system, such as a teeter-totter or seesaw.  The continuous asymmetrical loading from biomechanical dysfunction one side of the fulcrum requires a proportionate contraction of the muscles on the opposite side of the fulcrum to maintain upright posture. This counterbalance contraction of the muscles is both fatiguing to the muscle and increases the compressive loads on the fulcrum tissues that are considered predisposing factors for pain. Cailliet  explains how the constant contraction in the counterbalancing muscles creates a cascade that leads to muscle fatigue, inflammation, fibrosis, and eventually to functional disability.
Neurophysiologically, our results follow those of Harrison,  who reported that “abnormal posture of any part of the spinal column will induce abnormal stresses in the entire cord and nervous system while the normal posture will minimize these stresses.” On theoretic grounds, it can be assumed that postures of cervical spine will have direct effects on the thoracic cord, lumbar cord, and lumbosacral nerve roots. This concept was supported by many studies, which concluded that, with flexion of cervical spine, longitudinal stress and strain were found at all levels down to the lumbar spine. [52-54]
In contrast to our findings, a recent systematic review that investigated the relationship and effect of posture parameters on low back pain reported that postural abnormalities were of minor importance.  Similarly, an epidemiologic study of Dieck et al  reported that none of postural discrepancies in the posterior plane was associated with a subsequent report of low back pain, mid back pain, or neck pain.
Any contradictory findings between the association of posture and low back pain in the previous studies might be because of a lack of uniform classification and measurement, as most of the previous research was based on 2-dimensional posture analyses and poor experimental design because the previous contradictory findings were drawn from correlational studies that lacked a cause and effect relationship.
At the 2-year follow-up, it may be speculated that the patient improved because of the normal course of the lumbosacral radiculopathy. However, we found no statistically significant changes in the standard care group's outcomes. In this regard, Haugen et al  showed that 44% to 47% of the patients with sciatica who were referred for secondary care had a nonsuccessful outcome at 1 year and 39% to 42% at 2 years. The recurrence of radicular pain is relatively common after nonsurgical treatment of lumbar disc herniation. 
Limitations of the Study
The primary limitation for this study was the lack of investigator blinding. We educated physiotherapists and participants regarding the validity of both treatment arms and informed them that both should have a realistic potential for benefiting participants. We will inform them that there was no existing evidence to suggest that 1 treatment approach was superior to the other. Every effort was made to standardize treatment and assessment protocols to minimize potential bias from a lack of blinding. Blinding an independent outcomes assessor is highly recommended for future research. The different number of sessions provided to each group could be perceived as limitations of the trial. Attention-control visits can be used as a model in the design of future studies to control time and interaction with the physiotherapist and the effects of touching the patients. Another limitation is that the selection of patients was limited to lumbar hyperlordotic patients. Lumbar hyperlordosis is a common posture aberration in chronic low back pain patients,  and this abnormal posture may result from activation of the pelvo-ocular reflex to compensate for a forward head position,  which is the major concern in this study. The invasive nature of radiologic assessment was one of the major limitations in this study. However, radiologists strived to minimize the risk factor of x-rays by the use of high-frequency equipment to minimize the exposure times, shielding and filtration to block or reduce the x-ray beam from affecting sensitive tissues and areas of nondiagnostic interest, rare earth (intensifying) screens to decrease x-ray exposure by 50%, collimation to narrow the x-ray beam to include areas of interest only, and increased kilovoltage and minimized milliamperage to further reduce the x-ray dosage. Another limitation was the long-term follow-up period. However, it is admitted that structural correction with consequently functional changes requires a somewhat greater length of time than is required for symptomatic improvement. 
No attempt was made to control for the medications taken by the participants, which included opioid and nonopioid analgesics and nonsteroidal anti-inflammatory drugs. Medication use was similar at baseline, and no significant difference was found between the groups for the number of participants who managed pain with medication at the end of the 10-week treatment period. The only difference was found at the 2-year follow-up. This study did not test for psychological variables, which possibly influence the treatment outcomes, but this question may interest to address in further studies. Future research may investigate home care compliance rates and whether the extra training had any influence on compliance. Further studies also can be taken up using the same intervention procedures and parameters for other low back disorders.
Within these limitations, the unique contribution of our study is that it evaluated the independent effect that structural rehabilitation with forward head posture correction has on long-term global spinal posture in the transverse, coronal, and sagittal planes and on other outcome measures related to lumbar radiculopathy including disability, back and leg pain intensity, and S1 nerve root function, which, to the best of our knowledge, has not been previously reported. We hypothesized that the results of this study introduce new guidelines in the treatment of lumbosacral radiculopathy.
Adding forward head posture corrective exercises to a functional restoration program had a short- and long-term positive effect on 3-dimensional spinal posture in patients with chronic discogenic lumbosacral radiculopathy. After 10 weeks of treatment, the 2 treatment arms appeared to be equally successful in improving the lumbar radiculopathy management outcomes including disability, leg and back pain intensity, and neurophysiological findings. The long-term analysis, at the 2-year follow-up, revealed statistically significant changes favoring the outcome of the experimental group, including disability; neurophysiological findings represented in the H-reflex amplitude and H-reflex latency; and 3-dimensional postural parameters in terms of trunk inclination, lumbar lordosis, thoracic kyphosis, trunk imbalance, pelvic inclination, and surface rotation.