Cervical joint position sense is impaired in older adults

Clinical recognition of the role of the cervical spine in signs and symptoms of altered sensorimotor control

Together with visual and vestibular input the cervical spine is vital for sensorimotor control of head and eye movement control, general body postural stability adjustments and co-ordination. Altered cervical input in persons with neck disorders can lead to signs and symptoms of impaired sensorimotor control across and within several domains. Clinical assessment for differential diagnosis and to direct management of cervical related altered sensorimotor control is clearly required in many patients. This applies not only to patients with neck disorders but also in patients with, for example vestibular disorders or concussion, presenting with signs and symptoms of altered sensorimotor control where the cervical spine may have a role to play. This paper explores the research and current knowledge in relation to clinical measures of cervical related sensorimotor control. The feasibility, responsiveness, comparison to gold standards and potential of clinical measures of cervical related sensorimotor control to assist in differential diagnosis are considered where relevant. Future research directions should examine the full complement of psychometric properties of tests and consideration of any relationships of these measures to pain, dizziness, trauma and functional implications. Development of other measures as well as use in assessing response post management are also important directions. These clinical measures, along with a skilled interview and cervical musculoskeletal examination will enable clinicians to recognise and manage impaired cervical sensorimotor control in patients with neck disorders as well as determine the role of the cervical spine in many patients presenting with signs and symptoms of altered sensorimotor control.

Cervical mobility and cervical proprioception in relation to fall risk among older adults: a prospective cohort study

PURPOSE

Age-related decreases in cervical mobility and proprioception have previously been demonstrated. Potential associations of these deteriorations with fall risk have not been investigated so far. This study aims to compare cervical mobility and proprioception between fallers and non-fallers and prospectively assess the contribution of these parameters in fall risk identification among healthy older adults.

METHODS

95 community-dwelling older adults underwent a cervical screening. Active cervical range of motion (aCROM) was measured using a digital inclinometer and cervical proprioception was assessed by determining joint position error (JPE). Fear of falling was identified through the Iconographical Falls Efficacy Scale (iconFES). Falls were prospectively recorded during a 1-year follow-up period using monthly calendars. Univariate and multivariate logistic regression analyses were conducted to examine the association between these parameters and falls occurrence.

RESULTS

Baseline measurements revealed reduced cervical performance (i.e., smaller aCROM and larger JPE) among individuals who reported at least one fall during the following year ("fallers"). The multivariate logistic regression model contained eight independent variables (age, sex, walking aid, fall history, iconFES, aCROM F, aCROM E and JPE) and correctly classified 77.8% of cases.

CONCLUSION

Although the contribution of cervical parameters to fall risk identification seems to be rather small compared to well-known (though often unmodifiable) major risk factors, further research is needed to elucidate underlying mechanisms of cervical functions in relation to falls. Second, it would be interesting to develop a targeted fall preventive cervical exercise program and assess its effectiveness in terms of falls occurrence.

Neck Pain: Do We Know Enough About the Sensorimotor Control System?

Neck pain is a worldwide health problem. Clarifying the etiology and providing effective interventions are challenging for the multifactorial nature of neck pain. As an essential component of cervical spine function, the sensorimotor control system has been extensively studied in both healthy and pathological conditions. Proprioceptive signals generated from cervical structures are crucial to normal cervical functions, and abnormal proprioception caused by neck pain leads to alterations in neural plasticity, cervical muscle recruitment and cervical kinematics. The long-term sensorimotor disturbance and maladaptive neural plasticity are supposed to contribute to the recurrence and chronicity of neck pain. Therefore, multiple clinical evaluations and treatments aiming at restoring the sensorimotor control system and neural plasticity have been proposed. This paper provides a short review on neck pain from perspectives of proprioception, sensorimotor control system, neural plasticity and potential interventions. Future research may need to clarify the molecular mechanism underlying proprioception and pain. The existing assessment methods of cervical proprioceptive impairment and corresponding treatments may need to be systematically reevaluated and standardized. Additionally, new precise motor parameters reflecting sensorimotor deficit and more effective interventions targeting the sensorimotor control system or neural plasticity are encouraged to be proposed.

Effects of experimental pain on the cervical spine reposition errors

BACKGROUND

Healthy subjects showed normal variance of cervical spine reposition errors of approximately 2 degrees. Effects of experimental pain on cervical spine reposition errors were unknown; thus, the purpose of this study was to investigate the effects of experimental pain on cervical spine reposition errors.

METHODS

A repeated measured study design was applied. Thirty healthy subjects (12 males) were recruited. Reposition errors were extracted from upright cervical positions before and after cervical flexion movement in healthy subjects before and during experimental neck pain. Cervical spine reposition errors were calculated based on anatomical landmarks of each cervical joint. Reposition errors were extracted in degrees as constant errors and absolute errors for further statistical analysis. Repeated measures analysis of variance (RM-ANOVA) was applied to analyse experimental pain effects on either constant errors or absolute errors of different cervical joints.

RESULTS

The cervical spine showed non-significant difference in reposition errors regarding the constant errors (P>0.05) while larger reposition errors regarding the absolute errors during experimental pain compared to before experimental pain (P<0.001). In addition, the pain level joint (C4/C5) and its adjacent joints (C3/C4 and C5/C6) indicated larger reposition errors regarding absolute errors (P=0.035, P=0.329 and P=0.103, respectively).

CONCLUSIONS

This study firstly investigated the cervical spine reposition errors in experimental neck pain and further found the joints adjacent to the pain level showed larger errors compared to the distant joints regarding absolute errors. It may imply that the larger reposition errors in specific cervical joint indicate probable injury or pain existed adjacent to the joints.

Joint position error after neck protraction-retraction movements in healthy office workers: a cross-sectional study

Since the upper cervical spine (UCS) has been regarded to be distinct from the lower cervical spine (LCS), joint position error (JPE) needs to be tested separately for both regions. The purpose of this study was to investigate the JPE after cervical protraction/retraction movements, involving opposite movements of extension and flexion for the UCS and LCS. These movements are frequently performed during office work. Cervical JPEs were tracked in thirty healthy office workers while performing four tests of cervical pro-retraction movements with variations in vision and movement direction, and assessed using the Kinect head tracker (Microsoft Corp), placed in front of each participant. The JPE was expressed in constant (CE), absolute (AE) and variable errors (VE). Multilevel linear models evaluated main and interaction effects of vision, movement direction, cervical region and sex. Slightly larger JPEs have been found in the UCS. Vision showed no effect on any outcome variable. No effect exceeded typical measurement errors reported for the Kinect head tracker. This study showed, that JPEs after pro-retraction movements of the head and neck may differ for UCS and LCS. The differences were small and not beyond measurement error reported for the Kinect.

Age-related kinematic performance should be considered during fast head-neck rotation target task in individuals aged from 8 to 85 years old

Kinematic behavior during fast cervical rotations is a useful parameter for assessing sensorimotor control performances in neck-pain patients. However, the influence of age in asymptomatic individuals from children to older people still needs to be explored. Our aim was to assess the impact of age on sensorimotor control performance of the head-neck with execution time and kinematic variables (time of task, mean speed/acceleration/deceleration, overshoots (OSs), minimum/maximum speed) during standardized fast rotation target task using the DidRen Laser test. A total of 80 volunteers were stratified in four different age-groups: Children (8–14 years): n = 16; Young Adults (18–35 years): n = 29; Old Adults (36–64 years): n = 18; Seniors (65–85 years): n = 17. Results showed that to perform the test, Children were slower (69.0 (60.6–87.3)s) compared to Young Adults (49.6 (45.6–55.6)s) with p < 0.001, and Old Adults (51.7 (48.4–55.8)s) with p < 0.001. It was also slower in Seniors (57 (52.3–67.6)s) compared to Young Adults with p < 0.013. Mean speed was slower in Children (9.4 ± 2.3 °s⁻¹) and Seniors (10.6 ± 2.4 °s⁻¹) compared to Young Adults (13.7 ± 1.9 °s⁻¹) with p < 0.001 and Old Adults (13.3 ± 2.4 °s⁻¹) with p < 0.001. Mean acceleration was slower for Children (8.4(7.6–10.2) °s⁻²) compared to Young Adults (11.1 (8.8–15.3) °s⁻²) with p < 0.016, and Old Adults (12.0(8.4–15.3) °s⁻²) with p < 0.015. Mean deceleration was slower for Children (−1.9(−2.6–1.4) °s⁻²) compared to Young Adults (−2.9(−3.7–2.5) °s⁻²) with p < 0.001 and Old Adults (−3.2(−3.7–2.3) °s⁻²) with p < 0.003. The DidRen Laser test allows us to discriminate age-specific performances for mean speed, acceleration and deceleration. Seniors and Children needed to be slower to become as precise as Young Adults and Old Adults. No difference was observed for OSs which assesses accuracy of movement. Age should therefore be considered as a key parameter when analyzing execution time and kinematic results during DidRen Laser test. These normative data can therefore guide clinicians in the assessment of subjects with neck pain.

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.

Cervical spine reposition errors after cervical flexion and extension

BACKGROUND

Upright head and neck position has been frequently applied as baseline for diagnosis of neck problems. However, the variance of the position after cervical motions has never been demonstrated. Thus, it is unclear if the baseline position varies evenly across the cervical joints. The purpose was to assess reposition errors of upright cervical spine.

METHODS

Cervical reposition errors were measured in twenty healthy subjects (6 females) using video-fluoroscopy. Two flexion movements were performed with a 20 s interval, the same was repeated for extension, with an interval of 5 min between flexion and extension movements. Cervical joint positions were assessed with anatomical landmarks and external markers in a Matlab program. Reposition errors were extracted in degrees (initial position minus reposition) as constant errors (CEs) and absolute errors (AEs).

RESULTS

Twelve of twenty-eight CEs (7 joints times 4 repositions) exceeded the minimal detectable change (MDC), while all AEs exceeded the MDC. Averaged AEs across the cervical joints were larger after 5 min' intervals compared to 20 s intervals (p < 0.05).

CONCLUSIONS

This is the first study to demonstrate single joint reposition errors of the cervical spine. The cervical spine returns to the upright positions with a 2° average absolute difference after cervical flexion and extension movements in healthy adults.

Accuracy of Different Modalities to Record Natural Head Position in 3 Dimensions: A Systematic Review

PURPOSE

Three-dimensional (3D) images are taken with positioning devices to ensure a patient's stability, which, however, place the patient's head into a random orientation. Reorientation of images to the natural head position (NHP) is necessary for appropriate assessment of dentofacial deformities before any surgical planning. The aim of this study was to review the literature systematically to identify and evaluate the various modalities available to record the NHP in 3 dimensions and to compare their accuracy.

MATERIALS AND METHODS

A systematic literature search of the PubMed, Cochrane Library and Embase databases, with no limitations on publication time or language, was performed in July 2015. The search and evaluations of articles were performed in 4 rounds. The methodologies, accuracies, advantages, and limitations of various modalities to record NHP were examined.

RESULTS

Eight articles were included in the final review. Six modalities to record NHP were identified, namely 1) stereophotogrammetry, 2) facial markings along laser lines, 3) clinical photographs and the pose from orthography and scaling with iterations (POSIT) algorithm, 4) digital orientation sensing, 5) handheld 3D camera measuring system, and 6) laser scanning. Digital orientation sensing had good accuracy, with mean angular differences from the reference within 1° (0.07 ± 0.49° and 0.12 ± 0.54°, respectively). Laser scanning was shown to be comparable to digital orientation sensing. The method involving clinical photographs and the POSIT algorithm was reported to have good accuracy, with mean angular differences for pitch, roll, and yaw within 1° (-0.17 ± 0.50°). Stereophotogrammetry was reported to have the highest reliability, with mean angular deviations in pitch, roll, and yaw for active and passive stereophotogrammetric devices within 0.1° (0.004771 ± 0.045645° and 0.007572 ± 0.079088°, respectively).

CONCLUSIONS

This systematic review showed that recording the NHP in 3 dimensions with a digital orientation sensor has good accuracy. Laser scanning was found to have comparable accuracy to digital orientation sensing, but routine clinical use was limited by its high cost and low portability. Stereophotogrammetry and the method using a single clinical photograph and the POSIT algorithm were potential alternatives. Nevertheless, clinical trials are needed to verify their applications in patients. Preferably, digital orientation sensor should be used as a reference for comparison with new proposed methods of recording the NHP in future research.

Evidence of Impaired Proprioception in Chronic, Idiopathic Neck Pain: Systematic Review and Meta-Analysis

BACKGROUND

Despite common use of proprioceptive retraining interventions in people with chronic, idiopathic neck pain, evidence that proprioceptive dysfunction exists in this population is lacking. Determining whether proprioceptive dysfunction exists in people with chronic neck pain has clear implications for treatment prescription.

PURPOSE

The aim of this study was to synthesize and critically appraise all evidence evaluating proprioceptive dysfunction in people with chronic, idiopathic neck pain by completing a systematic review and meta-analysis.

DATA SOURCES

MEDLINE, CINAHL, PubMed, Allied and Complementary Medicine, EMBASE, Academic Search Premier, Scopus, Physiotherapy Evidence Database (PEDro), and Cochrane Collaboration databases were searched.

STUDY SELECTION

All published studies that compared neck proprioception (joint position sense) between a chronic, idiopathic neck pain sample and asymptomatic controls were included.

DATA EXTRACTION

Two independent reviewers extracted relevant population and proprioception data and assessed methodological quality using a modified Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) statement.

DATA SYNTHESIS

Thirteen studies were included in the present review. Meta-analysis on 10 studies demonstrated that people with chronic neck pain perform significantly worse on head-to-neutral repositioning tests, with a moderate standardized mean difference of 0.44 (95% confidence interval=0.25, 0.63). Two studies evaluated head repositioning using trunk movement (no active head movement thus hypothesized to remove vestibular input) and showed conflicting results. Three studies evaluated complex or postural repositioning tests; postural repositioning was no different between groups, and complex movement tests were impaired only in participants with chronic neck pain if error was continuously evaluated throughout the movement.

LIMITATIONS

A paucity of studies evaluating complex or postural repositioning tests does not permit any solid conclusions about them.

CONCLUSIONS

People with chronic, idiopathic neck pain are worse than asymptomatic controls at head-to-neutral repositioning tests.

Contribution of Head Position, Standing Surface, and Vision to Postural Control in Community-Dwelling Older Adults

Postural control requires the integration of sensorimotor information to maintain balance and to properly position and orient the body in response to external stimuli. Age-related declines in peripheral and central sensory and motor function contribute to postural instability and falls. This study investigated the contribution of head position, standing surface, and vision on postural sway in 26 community-dwelling older adults. Participants were asked to maintain a stable posture under conditions that varied standing surface, head position, and the availability of visual information. Significant main and interaction effects were found for all three factors. Findings from this study suggest that postural sway responses require the integration of available sources of sensory information. These results have important implications for fall risks in older adults and suggest that when standing with the head extended and eyes closed, older adults may place themselves at risk for postural disequilibrium and loss of balance.

Sensorimotor function of the cervical spine in healthy volunteers

BACKGROUND

Sensorimotor mechanisms are important for controlling head motion. However, relatively little is known about sensorimotor function in the cervical spine. This study investigated how age, gender and variations in the test conditions affect measures of position sense, movement sense and reflex activation in cervical muscles.

METHODS

Forty healthy volunteers (19M/21F, aged 19-59 years) participated. Position sense was assessed by determining repositioning errors in upright and flexed neck postures during tests performed in 25%, 50% and 75% cervical flexion. Movement sense was assessed by detecting thresholds to passive flexion and extension at velocities between 1 and 25°s(-1). Reflexes were assessed by determining the latency and amplitude of reflex activation in trapezius and sternocleidomastoid muscles. Reliability was evaluated from intraclass correlation coefficients.

FINDINGS

Mean repositioning errors ranged from 1.5° to 2.6°, were greater in flexed than upright postures (P=0.006) and in people aged over 25 years (P=0.05). Time to detect head motion decreased with increasing velocity (P<0.001) and was lower during flexion than extension movements (P=0.002). Reflexes demonstrated shorter latency (P<0.001) and greater amplitude (P=0.009) in trapezius compared to sternocleidomastoid, and became slower and weaker with age. None of the measures were influenced by gender. Reliability was good for movement sense measures, but was influenced by the test conditions when assessing position sense.

INTERPRETATION

Increased repositioning errors and slower reflexes in older subjects suggest that sensorimotor function in the cervical spine becomes impaired with age. In position sense tests, reliability was influenced by the test conditions with mid-range flexion movements, performed in standing, providing the most reliable measurements.

Determine the effect of neck muscle fatigue on dynamic visual acuity in healthy young adults

[Purpose] The aim of this study was to determine whether neck muscle fatigue affects dynamic visual acuity in healthy young participants. [Subjects and Methods] This study was a double-blinded, prospective, randomized, controlled trial. Thirty healthy young subjects (ages 21 to 30 years) participated in the study. Participants were randomly divided into an experimental group (n=15) and a control group (n=15). The experimental group performed an exercise designed to induce neck muscle fatigue and the control group preformed non-fatiguing sham exercises. [Results] There were significant differences in mean dynamic visual acuity between the two groups (0.26±0.11 LogMar versus 0.003±0.02 LogMar). Subjects in the experimental group showed a significant decline in their dynamic visual acuity compared with the control group. Dynamic visual acuity strongly correlated with neck muscle fatigue (r = 0.79). No significant differences in joint position error were observed between the two groups and no significant correlations between joint position error and neck muscle fatigue were observed (r = 0.23). [Conclusion] The results of this study suggest that neck muscle fatigue negatively impacts dynamic visual acuity. Although not statistically significant, cervical spine proprioception as measured by the joint position error in the experimental group was diminished after fatigue.

Discrimination of Amount of Spinal Flexion for Movements Made with and without Vision after Lumbar Disc Replacement

Discrimination of differences between small lumbar flexion movements made when standing may differ depending on whether vision is available. Dependence on general vision during trunk movements may be increased following surgery, in which an intervertebral disc is replaced with a prosthetic disc. This study investigated whether the availability of vision changed discrimination of small differences in lumbar forward flexion movement when standing for patients with lumbar disc replacement and healthy peers. 20 volunteers without a history of back pain and 20 with disc replacement undertook a 100-trial sequence of forward flexion movements to a set of physical stops, making an absolute judgement as to the position after each movement. General (nontarget) vision during the movement was available or removed randomly trial by trial. Availability of vision did not affect discrimination of flexion movements of the lumbar spine either in normal healthy individuals or those with disc replacement.

Effects of vision and tactile stimulation of the neck on postural control during unperturbed stance and cervical joint position sense in young asymptomatic adults

STUDY DESIGN

Before and after intervention trials.

OBJECTIVE

To evaluate the effects of visual input and tactile stimulation of the neck on postural control during unperturbed stance and cervical joint position sense.

SUMMARY OF BACKGROUND DATA

Although beneficial effects on lower-limb joints proprioception have been reported when vision was available and when tactile stimulation was applied around lower-limb joints, there has hitherto been no study investigating whether and how vision and tactile stimulation applied to the neck could modify postural control during unperturbed stance and joint position sense.

METHODS

The effects of visual input and tactile stimulation of the neck on postural control during unperturbed stance (Experiments 1 and 2) and cervical joint position sense (Experiments 3 and 4) were assessed in four separate experiments. During these experiments, two experimental tasks (a postural task during unperturbed stance and the CRT to NHP) were executed without (No vision) and with the availability of the vision (Vision) and without (No tactile stimulation condition) and with the application of strips of adhesive bandage to the skin over and around the neck (Tactile stimulation condition). Twelve different subjects participated in the four experiments.

RESULTS

For experiments 1 and 2, decreased centre of foot pressure displacements were observed in the Vision relative to the No vision and in the Tactile stimulation relative to the No tactile stimulation condition. For experiments 3 and 4, more accurate and more consistent repositioning performances were observed in the Vision relative to the No vision and in the Tactile stimulation relative to the No tactile stimulation condition, as indicated by decreased absolute and variable errors, respectively.

CONCLUSION

Altogether, our results suggest that subjects were able to take advantage of vision and increased neck cutaneous information provided by the by strips of adhesive bandage applied to the neck to improve postural control during unperturbed stance and cervical joint position sense.

Degradation of cervical joint position sense following muscular fatigue in humans

STUDY DESIGN

Before and after intervention trials.

OBJECTIVE

To investigate the effect of cervical muscular fatigue on joint position sense.

SUMMARY OF BACKGROUND DATA

Although fatigue-related degradation of proprioceptive acuity at lower and upper limbs is well documented, to date no study has investigated whether muscular fatigue induced at the neck could modify joint position sense.

METHODS

A total of 9 young healthy adults were asked to perform the cervicocephalic relocation test to the neutral head position, that is, to relocate the head on the trunk, as accurately as possible, after full active cervical rotation to the left and right sides. This experimental task was executed in 2 conditions of No fatigue and Fatigue of the scapula elevator muscles. Absolute and variable errors were used to assess the cervical joint repositioning accuracy and consistency, respectively.

RESULTS

Less accurate and less consistent repositioning performances were observed in Fatigue relative to No fatigue condition, as indicated by increased absolute and variable errors, respectively.

CONCLUSION

Results of the present experiment evidence that cervical joint position sense, assessed through the cervicocephalic relocation test to the neutral head position, is degraded by muscular fatigue.

The effect of free fly expertise on cervical joint position sense: a pilot study

This study aimed to assess the effect of free fly expertise on cervical joint position sense. To this aim, four young elite freeflyers and 20 young sportsmen nonfreeflyers were asked to perform the cervicocephalic relocation test to the neutral head position. During the test, they had to reposition their head in a neutral position on their trunk, as accurately as possible, after full active cervical rotation to the left and right. Absolute and variable errors were used to assess accuracy and consistency of the repositioning for the two groups. Absolute and variable errors observed in the group of freeflyers were significantly lower than those observed in the group of nonfreeflyers. These results suggest a more accurate and consistent head repositioning performance in the group of freeflyers than in the group of nonfreeflyers. The present findings suggest that the cervical joint position sense could be improved through extensive specific sports training.

Cervical proprioception is sufficient for head orientation after bilateral vestibular loss

The aim was to investigate the relative importance of cervical proprioception compared to vestibular input for head movements on trunk. Subjects with bilateral vestibulopathy (n = 11) were compared to healthy controls (n = 15). We studied their ability to move the head accurately to reproduce four specified target positions in the horizontal yaw plane (neutral head position, 10 degrees target, 30 degrees target, and 30 degrees target with oscillating movements applied during target introduction). Repositioning ability was calculated as accuracy (constant error, the mean of signed differences between introduced and reproduced target) and precision (variable error, the standard deviation of differences between introduced and reproduced targets). Subjects with bilateral vestibulopathy did not differ significantly from controls in their ability to reproduce different target positions. When the 30 degrees target position was introduced with oscillating movements, overshoot diminished and accuracy improved in both groups, although only statistically significantly when performed towards the right side. The results suggest that at least in some conditions, accurate head on trunk orientation can be achieved without vestibular information and that cervical somato-sensory input is either up-regulated as a compensatory mechanism after bilateral vestibular loss or is important for such tasks.