Repeated end range spinal movement while seated abolishes the proprioceptive deficit induced by prolonged flexed sitting posture. A study assessing the statistical and clinical significance of spinal position sense

Rehabilitation Practitioners' Perceptions of Optimal Sitting and Standing Posture in Men with Normal Weight and Obesity

The concepts of "optimal posture (OP)" and "harmful posture (HP)" are commonly used, and specific spinal postures can contribute to back pain. However, quantitative descriptions of optimal and harmful standing (StP) and sitting (SP) postures are currently lacking, particularly for different body mass indices (BMIs). Therefore, this study aimed to identify and quantify the OPs and HPs of StP and SP at different BMIs and investigate the attitudes and beliefs of rehabilitation practitioners toward OPs and HPs. Overall, 552 rehabilitation practitioners were recruited to participate in a questionnaire survey to select the optimal position from seven sitting and five standing postures for each BMI healthy volunteer. The segmental relationships of each posture were qualified using the Vicon software. For normal BMI, the physiotherapists chose two SPs (48.19% and 49.64%) and one StP (80.42%) as the OP. One sitting SP (83.7%) and two standing StPs (43.48% and 48.19%) were selected as optimal for obese BMI. All the most commonly selected OPs had an upright lordotic posture, while the postures with slouched spinal curves or forward head postures were almost all selected as HP. Additionally, 96.74% of participants considered education about optimal SP and StP to be "quite" or "very" important. The OP of the StP and SP postures was mostly based on the vertical alignment of gravity lines and sagittal balance. For obese people, the rehabilitation practitioners' observations may be erroneous, and further physical examination is necessary. Rehabilitation practitioners generally believe that postural education is essential in clinical practice.

Reliability of a three-dimensional spinal proprioception assessment for patients with adolescent idiopathic scoliosis

PURPOSE

Although it is evident that some patients with adolescent idiopathic scoliosis (AIS) have proprioceptive deficit in peripheral joints, knowledge on the proprioceptive function of the deformed spine is limited. Nonetheless, spinal proprioception in AIS may be affected three-dimensionally, prior studies only focussed on evaluating peripheral proprioception in single plane. Therefore, this study aimed to develop a novel spinal proprioception assessment using three-dimensional motion analysis in patients with AIS.

METHODS

Participants were included if they had a primary diagnosis of AIS who did not receive or failed conservative treatments. Three trunk repositioning tests involving flexion-extension, lateral-flexion, and axial-rotation were conducted. A three-dimensional kinematics of the trunk was used as the outcome measures. The proprioceptive acuity was quantified by the repositioning error. The intra-examiner and test-retest reliability were analysed by the intraclass correlation coefficient (ICC).

RESULTS

Fifty-nine patients with AIS were recruited. Regarding the trunk flexion-extension test, the single measure ICC showed moderate reliability (0.46) and the average measures ICC demonstrated good reliability (0.72). As for the trunk lateral-flexion test, the reliability of single measure and average measures ICC was moderate (0.44) and good (0.70) reliability, respectively. For the trunk axial-rotation test, the single measure ICC indicated fair reliability (0.32), while the average measures ICC showed moderate reliability (0.59).

CONCLUSION

This is the first study to evaluate the reliability of novel three-dimensional spinal proprioception assessments in patients with AIS. The trunk flexion-extension repositioning test may be preferable clinical test given its highest reliability.

Investigation of Joint Position Sense and Balance in Individuals With Chronic Idiopathic Neck Pain: A Cross-Sectional Study

OBJECTIVE

The aim of this study was to determine the relationship between joint position sense and static and dynamic balance in female patients with chronic neck pain compared with healthy controls.

METHODS

The study sample comprised 25 female patients with chronic neck pain and 25 healthy (asymptomatic) female controls. Pain severity with the visual analog scale, joint position sense with the laser pointer method, static balance with the Single-Leg Balance Test, and dynamic balance with the Y Balance Test were assessed.

RESULTS

The deviation in cervical joint position sense was greater in extension (P < .001), right rotation (P < .001), and left lateral rotation (P < .05) in the patients with chronic neck pain compared with the healthy controls. The results of the patients with chronic neck pain were worse than the healthy controls in the Single-Leg Balance Test with both eyes open (P < .05) and eyes closed (P < .05). The patients with chronic neck pain had worse dynamic balance only in the anterior direction reach of the left leg (P < .05).

CONCLUSION

Cervical joint position sense and static balance were worse in female patients with chronic idiopathic neck pain when compared with asymptomatic controls. Dynamic balance in all other directions except for the anterior direction was not negatively affected in individuals with chronic idiopathic neck pain.

Neck and back muscle chains hypomobility in women with migraine

OBJECTIVE

To compare the mobility of neck and back flexor and extensor muscle chains in women with migraine, chronic migraine and headache-free.

METHODS

This is a cross-sectional study. The muscle chain test was performed based on the theoretical assumptions of the Busquet method, in women with migraine (MG, n = 24), chronic migraine (CMG, n = 36) and headache-free (CG, n = 27). The evaluation of neck and back mobility was performed by an examiner expert in the Busquet method with the aid of cervical range of motion (CROM®) device (neck muscles) and the Tiltmeter® application (back muscles).

RESULTS

Compared to woman headache-free, women with migraine (MD = -12° [CI95% = -19°, -5°] and chronic migraine (MD = -15° [CI95% = -21°, -8°] present reduced mobility in the neck extensor muscle chain. Also, in the back extensor muscle chain, migraine vs headache-free (MD = -9° [CI95% = -15°, -2°]) and chronic migraine vs headache-free (MD = -10° [CI95% = -16°, -4°]) and in the back flexor muscle chain, migraine vs headache-free (MD = -6° [CI95% = -10°, -0.1°]) and chronic migraine vs headache-free (MD = -7 [CI95% = -11°, -2°]), with an effect sizes varying between 1.19 e 2.38. No difference was found between groups for neck flexor muscle chain.

CONCLUSION

Women with migraine and chronic migraine have hypomobility of the neck and back extensor muscle chains, and of the back flexor chain.

Lumbo-pelvic proprioception in sitting is impaired in subgroups of low back pain-But the clinical utility of the differences is unclear. A systematic review and meta-analysis

BACKGROUND

Altered spinal postures and altered motor control observed among people with non-specific low back pain have been associated with abnormal processing of sensory inputs. Evidence indicates that patients with non-specific low back pain have impaired lumbo-pelvic proprioceptive acuity compared to asymptomatic individuals.

OBJECTIVE

To systematically review seated lumbo-pelvic proprioception among people with non-specific low back pain.

METHODS

Five electronic databases were searched to identify studies comparing lumbo-pelvic proprioception using active repositioning accuracy in sitting posture in individuals with and without non-specific low back pain. Study quality was assessed by using a modified Downs and Black's checklist. Risk of bias was assessed using an adapted tool for cross-sectional design and case-control studies. We performed meta-analysis using a random effects model. Meta-analyses included subgroup analyses according to disability level, directional subgrouping pattern, and availability of vision during testing. We rated the quality of evidence using the GRADE approach.

RESULTS

16 studies met the eligibility criteria. Pooled meta-analyses were possible for absolute error, variable error, and constant error, measured in sagittal and transverse planes. There is very low and low certainty evidence of greater absolute and variable repositioning error in seated tasks among non-specific low back pain patients overall compared to asymptomatic individuals (sagittal plane). Subgroup analyses indicate moderate certainty evidence of greater absolute and variable error in seated tasks among directional subgroups of adults with non-specific low back pain, along with weaker evidence (low-very low certainty) of greater constant error.

DISCUSSION

Lumbo-pelvic proprioception is impaired among people with non-specific low back pain. However, the low certainty of evidence, the small magnitude of error observed and the calculated "noise" of proprioception measures, suggest that any observed differences in lumbo-pelvic proprioception may be of limited clinical utility.

PROSPERO-ID

CRD42018107671.

Lower spinal postural variability during laptop-work in subjects with cervicogenic headache compared to healthy controls

Spinal postural variability (SPV) is a prerequisite to prevent musculoskeletal complaints during functional tasks. Our objective was to evaluate SPV in cervicogenic headache (CeH) since CeH is characterized by such complaints. A non-randomized repeated-measure design was applied to compare SPV between 18 participants with reporting CeH aged 29–51 years, and 18 matched controls aged 26–52 years during a 30-min-laptop-task. Habitual spinal postures (degrees) of the cervical, thoracic and lumbar spine were analysed using 3D-Vicon motion analysis. SPV, to express variation in mean habitual spinal posture, was deducted from the postural analysis. Mean SPV of each spinal segment was lower in the CeH-group compared to the control-group. Within the CeH-group, SPV of all except one spinal segment (lower-lumbar) was higher compared to the group’s mean SPV. Within the control-group, SPV was more comparable to the group’s mean SPV. SPV differed between groups. Averaging data resulted in decreased SPV in the CeH-group compared to the control-group during the laptop-task. However, the higher within-group-SPV in the CeH-group compared to the group’s mean SPV accentuated more postural heterogeneity. It should be further determined if addressing individual SPV is a relevant intervention.

Notions of "optimal" posture are loaded with meaning. Perceptions of sitting posture among asymptomatic members of the community

BACKGROUND

Notions of "optimal" posture are widespread in modern society and strongly interconnected with preconceived beliefs.

OBJECTIVES

To quantitatively evaluate spinal posture among members of the community during habitual sitting, and when asked to assume an "optimal" posture.

DESIGN

Observational study.

METHODS

Marker-based kinematic analyses of the head, spine, and pelvis were conducted on 100 individuals. Habitual sitting posture and self-perceived "optimal" posture, and whether participants believed that their habitual sitting reflected an "optimal" posture, were evaluated. The Wilcoxon signed-rank test assessed angular differences between the two postures adopted. Exploratory post-hoc analyses were conducted by using the Mann-Whitney U test to assess differences between genders.

RESULTS

None of the participants stated that their habitual sitting was "optimal". Statistically significant differences were observed in most of the measured angles (p < 0.001) between habitual and self-perceived "optimal" posture. In habitual sitting posture, a significant interaction with gender was found only in the thoracolumbar (p < 0.05) and pelvic (p < 0.001) angles, with small effect sizes. In self-perceived "optimal" posture females were more extended in the head, upper thoracic, lower thoracic, lumbar and pelvic (p < 0.01) regions, than the males.

CONCLUSIONS

A group of young, asymptomatic participants, consistently changed their habitual sitting posture to a more upright posture when asked to assume an "optimal" sitting posture, although the amount of change observed varied between spinal regions. These findings also highlight gender differences in not just habitual sitting posture, but also the degree to which habitual sitting posture is modified when trying to assume an "optimal" sitting posture.

Physiotherapist perceptions of optimal sitting and standing posture

BACKGROUND

Assessment of, and advice about, spinal posture is common when people with spinal pain present to physiotherapists. Most descriptions regarding optimal spinal posture have been qualitative in nature.

OBJECTIVES

To determine the beliefs of physiotherapists regarding optimal sitting and standing posture.

DESIGN

Online survey.

METHOD

544 Greek physiotherapists selected an optimal sitting (choice of seven) and standing (choice of five) posture, while providing justification for their choice.

RESULTS

Education regarding optimal sitting and standing posture was considered "considerably" or "very" important by 93.9% of participants. Three different sitting postures, and two different standing postures, were selected as the optimal posture by 97.5% and 98.2% of physiotherapists respectively. While this reflects a lack of complete consensus on optimal posture, the most commonly selected postures were all some variation of upright lordotic sitting, in contrast slouched spinal curves (sitting) or forward head posture (sitting and standing) almost never being selected as optimal. Interestingly, participants used similar arguments (e.g. natural curves, muscle activation) to justify their selection regardless of the spinal configuration of each selected posture.

CONCLUSIONS

These results reinforce previous data suggesting that upright lordotic sitting postures are considered optimal, despite a lack of strong evidence that any specific posture is linked to better health outcomes. While postural re-education may play a role in the management of spinal pain for some patients, awareness of such widespread and stereotypical beliefs regarding optimal posture may be useful in clinical assessment and management.

Disturbance of neck proprioception and feed-forward motor control following static neck flexion in healthy young adults

The highly complex proprioceptive system provides neuromuscular control of the mobile cervical spine. Static neck flexion can induce the elongation of posterior tissues and altered afferent input from the mechanoreceptors. The purpose of this study was to examine the effect of prolonged static neck flexion on neck proprioception and anticipatory postural adjustments. Thirty-eight healthy participants (20 females and 18 males) between the ages of 20-35 years with no history of neck, low back, and shoulder pain enrolled in this study. Neck proprioception and anticipatory muscle activity were tested before and after 10-min static neck flexion. For assessment of neck proprioception, each participant was asked to perform 10 trials of the cervicocephalic relocation test to the neutral head position after active neck rotation to the left and right sides. Anticipatory postural adjustments were evaluated during a rapid arm flexion test. Following the flexion, the absolute and variable errors in head repositioning significantly increased (p < 0.05). The results also showed that there was a significant delay in the onset of myoelectric activity of the cervical erector spinae muscles after flexion (p = 0.001). The results of this study suggested that a 10-min static flexion can lead to changes in the neck proprioception and feed-forward control due to mechanical and neuromuscular changes in the viscoelastic cervical spine structures. These changes in sensory-motor control may be a risk factor for neck pain and injury.