Demonstration of central conduction time and neuroplastic changes after cervical lordosis rehabilitation in asymptomatic subjects: a randomized, placebo-controlled trial

Cognitive Load and Dual-Task Performance in Individuals with and without Forward Head Posture

Background: Recent studies have found forward head posture (FHP) is associated with altered physiology. There is a lack of research into whether FHP is associated with altered gait parameters when cognitively challenged. Our hypothesis is that individuals with FHP and those without will demonstrate different responses when undergoing dual-task assessment. Methods: Forty-five asymptomatic participants with FHP, defined as a craniovertebral angle (CVA) < 50°, were matched to forty-five participants with normal head posture (NHP) with a CVA > 55°. Participants walked along a 10 m platform under a control condition (no cognitive load) while an optical motion-capture system assessed gait kinematics. Secondly, participants were assessed under a dual-task cognitive load condition to identify the impact on gait kinematics. Results: Under the single-task condition, there were no significant differences for any gait parameter. In the dual-task condition, 12/13 gait parameters were significantly altered for the FHP vs. NHP group (p < 0.01). A calculation of the dual-task cost (DTC) percentage showed significant increases in all gait parameters in participants with FHP (p < 0.02). Correlations between the CVA and gait parameters were not significant for the single-task condition, but all gait parameters were correlated to CVA for the dual-task condition (p < 0.01). The correlation between CVA and DTC for all gait variables was significant (p < 0.04). Conclusions: This study demonstrates that FHP significantly increases the cognitive cost during walking, highlighting the importance of proper postural alignment for maintaining cognitive function under a dual-task condition.

Utilizing machine learning to predict post-treatment outcomes in chronic non-specific neck pain patients undergoing cervical extension traction

This study explored the application of machine learning in predicting post-treatment outcomes for chronic neck pain patients undergoing a multimodal program featuring cervical extension traction (CET). Pre-treatment demographic and clinical variables were used to develop predictive models capable of anticipating modifications in cervical lordotic angle (CLA), pain and disability of 570 patients treated between 2014 and 2020. Linear regression models used pre-treatment variables of age, body mass index, CLA, anterior head translation, disability index, pain score, treatment frequency, duration and compliance. These models used the sci-kit-learn machine learning library within Python for implementing linear regression algorithms. The linear regression models demonstrated high precision and accuracy, and effectively explained 30-55% of the variability in post-treatment outcomes, the highest for the CLA. This pioneering study integrates machine learning into spinal rehabilitation. The developed models offer valuable information to customize interventions, set realistic expectations, and optimize treatment strategies based on individual patient characteristics as treated conservatively with rehabilitation programs using CET as part of multimodal care.

Two Methods of Forward Head Posture Assessment: Radiography vs. Posture and Their Clinical Comparison

Background: Forward head posture (FHP) and altered cervical lordotic curvatures are common spine displacements often associated with neck pain and disability. Two primary categories for determining FHP exist: radiographic and postural measurements. Methods: This study investigated the correlation between the craniovertebral angle (CVA), the radiographically measured C2-C7 sagittal vertical axis (SVA), and cervical lordosis (absolute rotation angle: ARA C2-C7) in a sample of participants with chronic myofascial pain (CMP). In 120 participants, we performed both a postural measurement of the CVA and a lateral cervical radiograph, where the C2-C7 SVA and ARA C2-C7 were measured. A linear-regression R2 value to assess the correlation between the CVA, C2-C7 SVA, and ARA C2-C7 was sought. Results: A statistically significant weak linear fit was identified (Spearman's r = 0.549; R2 = 0.30, p < 0.001) between the CVA and C2-C7 SVA, having considerable variation between the two measures. A statistically significant linear fit (very weak) was identified for the lordosis ARA C2-C7 and the CVA: Spearman's r = 0.524; R2 = 0.275; p < 0.001. A value of 50° for the CVA corresponded to a value of 20 mm for the C2-C7 SVA on an X-ray. Conclusion: While the CVA and radiographic C2-C7 SVA are weakly correlated in an individual, they seem to represent different aspects of sagittal cervical balance. The CVA cannot replace radiographically measured cervical lordosis. We recommend that more emphasis be given to radiographic measures of sagittal cervical alignment than the CVA when considering patient interventions.

Is Thoracic Kyphosis Relevant to Pain, Autonomic Nervous System Function, Disability, and Cervical Sensorimotor Control in Patients with Chronic Nonspecific Neck Pain?

There is great interest in thoracic kyphosis, as it is thought to be a contributor to neck pain, neck disability, and sensorimotor control measures; however, this has not been completely investigated in treatment or case control studies. This case control design investigated participants with non-specific chronic neck pain. Eighty participants with a defined hyper-kyphosis (>55°) were compared to eighty matched participants with normal thoracic kyphosis (<55°). Participants were matched for age and neck pain duration. Hyper-kyphosis was further categorized into two distinct types: postural kyphosis (PK) and Scheuermann's kyphosis (SK). Posture measures included formetric thoracic kyphosis and the craniovertebral angle (CVA) to assess forward head posture. Sensorimotor control was assessed by the following measures: smooth pursuit neck torsion test (SPNT), overall stability index (OSI), and left and right rotation repositioning accuracy. A measure of autonomic nervous system function included the amplitude and latency of skin sympathetic response (SSR). Differences in variable measures were examined using the Student's t-test to compare the means of continuous variables between the two groups. One-way ANOVA was used to compare mean values in the three groups: postural kyphosis, Scheuermann's kyphosis, and normal kyphosis group. Pearson correlation was used to evaluate the relationship between participant's thoracic kyphosis magnitude (in each group separately and as an entire population) and their CVA, SPNT, OSI, head repositioning accuracy, and SSR latency and amplitude. Hyper-kyphosis participants had a significantly greater neck disability index compared to the normal kyphosis group (p < 0.001) with the SK group having greatest disability (p < 0.001). Statistically significant differences between the two kyphosis groups and the normal kyphosis group for all the sensorimotor measured variables were identified with the SK group having the most decreased efficiency of the measures in the hyper-kyphosis group, including: SPNT, OSI, and left and right rotation repositioning accuracy. In addition, there was a significant difference in neurophysiological findings for SSR amplitude (entire sample of kyphosis vs. normal kyphosis, p < 0.001), but there was no significant difference for SSR latency (p = 0.07). The CVA was significantly greater in the hyper-kyphosis group (p < 0.001). The magnitude of the thoracic kyphosis correlated with worsening CVA (with the SK group having the smallest CVA; p < 0.001) and the magnitude of the decreased efficiency of the sensorimotor control measures and the amplitude and latency of the SSR. The PK group, overall, showed the greatest correlations between thoracic kyphosis and measured variables. Participants with hyper-thoracic kyphosis exhibited abnormal sensorimotor control and autonomic nervous system dysfunction compared to those with normal thoracic kyphosis.

Does Forward Head Posture Influence Somatosensory Evoked Potentials and Somatosensory Processing in Asymptomatic Young Adults?

The current investigation used somatosensory evoked potentials (SEPs) to assess differences in sensorimotor integration and somatosensory processing variables between asymptomatic individuals with and without forward head posture (FHP). We assessed different neural regions of the somatosensory pathway, including the amplitudes of the peripheral N9, spinal N13, brainstem P14, peak-to-peak amplitudes of parietal N20 and P27, and frontal N30 potentials. Central conduction time (N13-N20) was measured as the difference in peak latencies of N13 and N20. We measured these variables in 60 participants with FHP defined as a craniovertebral angle (CVA) < 50° and 60 control participants matched for age, gender, and body mass index (BMI) with normal FHP defined as CVA > 55°. Differences in variable measures were examined using the parametric t-test. Pearson's correlation was used to evaluate the relationship between the CVA and sensorimotor integration and SEP measurements. A generalized linear model (GLM) was used to compare the SEP measures between groups, with adjustment for educational level, marital status, BMI, and working hours per week. There were statistically significant differences between the FHP group and control group for all sensorimotor integration and SEP processing variables, including the amplitudes of spinal N13 (p < 0.005), brainstem P14 (p < 0.005), peak-to-peak amplitudes of parietal N20 and P27 (p < 0.005), frontal N30 potentials (p < 0.005), and the conduction time N13-N20 (p = 0.004). The CVA significantly correlated with all measured neurophysiological variables indicating that as FHP increased, sensorimotor integration and SEP processing became less efficient. FHP group correlations were: N9 (r = -0.44, p < 0.001); N13 (r = -0.67, p < 0.001); P14 (r = -0.58, p < 0.001); N20 (r = -0.49, p = 0.001); P27 (r = -0.58, p < 0.001); N30 potentials (r = -0.64, p < 0.001); and N13-N20 (r = -0.61, p < 0.001). GLM identified that increased working hours adversely affected the SEP measures (p < 0.005), while each 1° increase in the CVA was associated with improved SEP amplitudes and more efficient central conduction time (N13-N20; p < 0.005). Less efficient sensorimotor integration and SEP processing may be related to previous scientific reports of altered sensorimotor control and athletic skill measures in populations with FHP. Future investigations should seek to replicate our findings in different spine disorders and symptomatic populations in an effort to understand how improving forward head posture might benefit functional outcomes of patient care.

Post-concussion syndrome and concussion incidence improved in a pro rugby player following cervical spine rehab: case study and 6-year follow-up

Aim

To report improvements in post-concussion syndrome and concussion incidence following cervical spinal alignment correction.

Case presentation

A 27-year-old professional rugby player with 20 documented concussions presented with abnormal cervical spinal alignment and post-concussion syndrome. After 30 sessions of cervical rehabilitation, health outcomes improved. Post-treatment radiographs showed improved cervical lordosis from -13.5° to -37.4° (ideal is -42°) and right head translation from -22.7 to -11.3 mm (ideal is 0 mm). 2-year follow-up radiographs and 6-year follow-up health outcomes showed post-treatment improvements were maintained. The patient reported two documented concussions in the 6 years following treatment while maintaining the same lifestyle and professional rugby career.

Conclusion

Correction of abnormal cervical spinal alignment may help athletes with post-concussion syndrome and reduce risk of concussion.

Re-establishing the cervical lordosis after whiplash: a Chiropractic Biophysics® spinal corrective care methods pre-auto injury and post-auto injury case report with follow-up

[Purpose] To document the re-establishment of the cervical lordosis following radiographically verified altered sagittal plane alignment both prior to, and following a motor vehicle collision. [Participant and Methods] A 16-year-old male presented for a non-motor collision complaint of low back pain. Initial lateral cervical radiograph demonstrated cervical hypo-lordosis. The patient was treated with a 6-week plan (18 visits) utilizing Chiropractic BioPhysics® (CBP) methods to increase the cervical lordosis. Eight months later the patient presented with new complaints as a result of a motor collision. The cervical lordosis straightened. The patient received another round of similar treatment to improve the lordosis. There was also a 6.5-month follow-up. [Results] The initial round of treatment achieved a 21° improvement in cervical lordosis. The motor vehicle collision caused a loss of 15° of lordosis. The second round of treatment achieved a 12.5° improvement in lordosis that was demonstrated to be maintained at a 6.5-month follow-up. [Conclusions] This case illustrates how a whiplash event occurring during a motor vehicle collision subluxated the cervical spine. It was also shown that CBP methods reliably corrected the lordosis after two separate treatment programs using specialized methods. Beyond trauma, radiographic screening of specific cervical subluxation is recommended following all motor collisions.

Sensorimotor integration, cervical sensorimotor control, and cost of cognitive-motor dual tasking: Are there differences in patients with chronic whiplash-associated disorders and chronic idiopathic neck pain compared to healthy controls?

PURPOSE

The current investigation aimed to compare the sensorimotor integration, sensorimotor control, and cost of cognitive-motor dual task during walking, in persons with chronic WAD as compared to matched chronic idiopathic neck pain and normal healthy controls.

METHODS

A cross-sectional, case control design comparing 30 participants in each of two study groups (chronic WAD and chronic idiopathic neck pain) to a matched control group was conducted. Measurements included: (1) the cranio-vertebral angle (CVA), (2) left and right rotation head repositioning accuracy (HRA), (3) frontal N30 amplitudes to assess sensorimotor integration, (4) dual cognitive gait cost (DCGC).

RESULTS

A statistically significant difference for the CVA was found between groups: WAD 36.8° ± 3.4, chronic pain 44.5° ± 1.5, and controls 47.1° ± 4; p < 0.05. MANOVA revealed significant group differences for the N30 amplitude (p < 0.05), where the WAD group had the greatest amplitude. Statistically significant differences among the three groups were found for HRA left and right where the WAD group had the greatest error, (p < 0.05). Post hoc tests revealed that the WAD group had the highest dual-task cost during walking, (p < 0.05). Significant linear correlations between the CVA and N30 amplitude, HRA, and DCGC were identified in all 3 groups, (p < 0.05).

CONCLUSIONS

Compared to both a matched control group and chronic neck pain group, whiplash-injured persons have greater forward head posture, greater error in sensorimotor control, and an altered ability to perform a motor task with a simultaneous cognitive task.

Does Improvement towards a Normal Cervical Sagittal Configuration Aid in the Management of Lumbosacral Radiculopathy: A Randomized Controlled Trial

A randomized controlled study with a six-month follow-up was conducted to investigate the effects of sagittal head posture correction on 3D spinal posture parameters, back and leg pain, disability, and S1 nerve root function in patients with chronic discogenic lumbosacral radiculopathy (CDLR). Participants included 80 (35 female) patients between 40 and 55 years experiencing CDLR with a definite hypolordotic cervical spine and forward head posture (FHP) and were randomly assigned a comparative treatment control group and a study group. Both groups received TENS therapy and hot packs, additionally, the study group received the Denneroll cervical traction orthotic. Interventions were applied at a frequency of 3 x per week for 10 weeks and groups were followed for an additional 6-months. Radiographic measures included cervical lordosis (CL) from C2–C7 and FHP; postural measurements included: lumbar lordosis, thoracic kyphosis, trunk inclination, lateral deviation, trunk imbalance, surface rotation, and pelvic inclination. Leg and back pain scores, Oswestry Disability Index (ODI), and H-reflex latency and amplitude were measured. Statistically significant differences between the groups at 10 weeks were found: for all postural measures, CL (p = 0.001), AHT (p = 0.002), H-reflex amplitude (p = 0.007) and latency (p = 0.001). No significant difference for back pain (p = 0.2), leg pain (p = 0.1) and ODI (p = 0.6) at 10 weeks were identified. Only the study group’s improvements were maintained at the 6-month follow up while the control groups values regressed back to baseline. At the 6-month follow-up, it was identified in the study group that improved cervical lordosis and reduction of FHP were found to have a positive impact on 3D posture parameters, leg and back pain scores, ODI, and H-reflex latency and amplitude.

Is the cervical lordosis a key biomechanical biomarker in cervicogenic headache?: a Chiropractic Biophysics® case report with follow-up

[Purpose] To present the successful structural improvement in cervical lordosis in a patient suffering from cervicogenic headache having cervical kyphosis. [Participant and Methods] A 26 year old female presented with the primary complaint of headache. Radiography demonstrated a cervical kyphosis. Chiropractic BioPhysics^® methods were used to restore the cervical spine alignment. Twenty-five treatments were given over 8 weeks. A 2.5 year follow-up was also reported. [Results] Radiography showed a dramatic increase in cervical lordosis following initial treatment. The patient also reported substantial reductions in headache frequency and severity as well as other bodily improvements, reduced disability and improved quality of life. The long-term follow-up showed a maintenance of lordosis correction and patient wellness. [Conclusion] A cervical kyphosis was reversed back to a normal lordosis in 8 weeks and coincided with dramatic resolution of cervicogenic headache in a young female. The cervical lordosis may be a key biomechanical biomarker in cervicogenic headache.

Improving the cervical lordosis relieves neck pain and chronic headaches in a pediatric: a Chiropractic Biophysics® (CBP®) case report with a 17-month follow-up

[Purpose] To present the case of a dramatic improvement in the cervical lordosis and relief from chronic headaches and neck pain in a pediatric having a recent neck trauma. [Participant and Methods] A 10 year old male presented with recent neck trauma, neck pain and pre-existing chronic headaches. Cervical range of motion was limited with pain. X-ray analysis showed dramatic loss of cervical lordosis and an acute atlantoaxial rotatory fixation. Chiropractic Biophysics technique methods incorporating spinal manual adjustments, cervical extension traction and corrective exercises were used to restore normal cervical lordosis. Treatments were performed intensively over 6.5-weeks, with a 17-month long-term follow-up. [Results] The pediatric patient responded well to treatment with near complete resolution of cranio-cervical complaints. The cervical lordosis was corrected to age-appropriate magnitude, the coronal symmetry was restored, and both were maintained after nearly 1.5 years. [Conclusion] Chiropractic Biophysics technique which includes the cervical extension traction using the pediatric Denneroll orthotic was effective in restoring lordosis in a pediatric patient with cervical kyphosis and chronic headaches presenting with recent neck pains from a traumatic origin. Routine X-ray of the cervical spine is recommended for patients presenting with craniocervical symptoms as spine alignment is often overlooked as pathognomonic for these conditions.