Joint position sense error in people with neck pain: A systematic review

Dizziness, Unsteadiness, Visual Disturbances, and Sensorimotor Control in Traumatic Neck Pain

Synopsis There is considerable evidence to support the importance of cervical afferent dysfunction in the development of dizziness, unsteadiness, visual disturbances, altered balance, and altered eye and head movement control following neck trauma, especially in those with persistent symptoms. However, there are other possible causes for these symptoms, and secondary adaptive changes should also be considered in differential diagnosis. Understanding the nature of these symptoms and differential diagnosis of their potential origin is important for rehabilitation. In addition to symptoms, the evaluation of potential impairments (altered cervical joint position and movement sense, static and dynamic balance, and ocular mobility and coordination) should become an essential part of the routine assessment of those with traumatic neck pain, including those with concomitant injuries such as concussion and vestibular or visual pathology or deficits. Once adequately assessed, appropriate tailored management should be implemented. Research to further assist differential diagnosis and to understand the most important contributing factors associated with abnormal cervical afferent input and subsequent disturbances to the sensorimotor control system, as well as the most efficacious management of such symptoms and impairments, is important for the future. J Orthop Sports Phys Ther 2017;47(7):492-502. Epub 16 Jun 2017. doi:10.2519/jospt.2017.7052.

A videofluoroscopy-based tracking algorithm for quantifying the time course of human intervertebral displacements

The motions of individual intervertebral joints can affect spine motion, injury risk, deterioration, pain, treatment strategies, and clinical outcomes. Since standard kinematic methods do not provide precise time-course details about individual vertebrae and intervertebral motions, information that could be useful for scientific advancement and clinical assessment, we developed an iterative template matching algorithm to obtain this data from videofluoroscopy images. To assess the bias of our approach, vertebrae in an intact porcine spine were tracked and compared to the motions of high-contrast markers. To estimate precision under clinical conditions, motions of three human cervical spines were tracked independently ten times and vertebral and intervertebral motions associated with individual trials were compared to corresponding averages. Both tests produced errors in intervertebral angular and shear displacements no greater than 0.4° and 0.055 mm, respectively. When applied to two patient cases, aberrant intervertebral motions in the cervical spine were typically found to correlate with patient-specific anatomical features such as disc height loss and osteophytes. The case studies suggest that intervertebral kinematic time-course data could have value in clinical assessments, lead to broader understanding of how specific anatomical features influence joint motions, and in due course inform clinical treatments.

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.

Translation and validation of Neck Bournemouth Questionnaire to Brazilian Portuguese

OBJECTIVE

To translate the Neck Bournemouth Questionnaire to Brazilian Portuguese, cross-culturally adapt, and to verify its validity and its reliability.

METHODS

The development of the Brazilian version of Neck Bournemouth Questionnaire (Brazil-NBQ) was based on the guideline proposed by Guillemin. The applied process consisted of translation, back-translation, committee review and pre-test. Sixty-one volunteers presenting neck pain participated in this study. Thirty-five of them participated during pre-testing phase to verify the instrument comprehension, and the remaining 26 took part during psychometric analysis. Psychometric evaluation included interrater and intrarater reliability and construct validity (correlation among Brazil-NBQ, SF-36, Numerical rating score and Neck Disability Index).

RESULTS

Some terms and expressions were changed to obtain cultural equivalence for Brazil-NBQ during the translation phase. The NBQ showed an intrarater ICC of 0.96 and interrater ICC of 0.87. Construct validity analysis showed moderate correlations with SF-36 and strong correlation with Numerical rating score and Neck Disability Index.

CONCLUSION

Neck Bournemouth Questionnaire was translated and culturally adapted to Portuguese language, and it demonstrated to be valid and reliable to evaluate patients' neck pain.

Effects of wearing ankle weight on knee joint repositioning sense in the elderly

[Purpose] To investigate the effects of different ankle weights on knee joint repositioning sense in elderly individuals. [Subjects and Methods] Twenty-one subjects were divided for assessment as follows: young (20–30 years, n=10) and elderly (60–70 years, n=11). Knee joint repositioning error was measured by asking the subjects to reposition the target angle of their knee joints while wearing different ankle weights (0%, 0.5%, 1%, and 1.5%) in an open kinetic chain. The Hawk Digital System (60 Hz; Motion Analysis, Santa Rosa, CA, USA) was used to measure knee joint repositioning error. Differences in knee joint repositioning error between the young and elderly groups according to ankle weight load were examined by using two-way mixed repeated-measures analysis of variance. [Results] The knee joint repositioning error was lower with than without ankle weights in both groups. The error value was lowest with the 1.0% weight, though not significantly. Knee joint repositioning error was significantly higher in the elderly under all the ankle weight conditions. [Conclusion] Knee joint repositioning sense can be improved in elderly individuals by wearing proper ankle weights. However, weights that are too heavy might disturb knee joint positioning sense.

Cervico-ocular Reflex Is Increased in People With Nonspecific Neck Pain

BACKGROUND

Neck pain is a widespread complaint. People experiencing neck pain often present an altered timing in contraction of cervical muscles. This altered afferent information elicits the cervico-ocular reflex (COR), which stabilizes the eye in response to trunk-to-head movements. The vestibulo-ocular reflex (VOR) elicited by the vestibulum is thought to be unaffected by afferent information from the cervical spine.

OBJECTIVE

The aim of the study was to measure the COR and VOR in people with nonspecific neck pain.

DESIGN

This study utilized a cross-sectional design in accordance with the STROBE statement.

METHODS

An infrared eye-tracking device was used to record the COR and the VOR while the participant was sitting on a rotating chair in darkness. Eye velocity was calculated by taking the derivative of the horizontal eye position. Parametric statistics were performed.

RESULTS

The mean COR gain in the control group (n=30) was 0.26 (SD=0.15) compared with 0.38 (SD=0.16) in the nonspecific neck pain group (n=37). Analyses of covariance were performed to analyze differences in COR and VOR gains, with age and sex as covariates. Analyses of covariance showed a significantly increased COR in participants with neck pain. The VOR between the control group, with a mean VOR of 0.67 (SD=0.17), and the nonspecific neck pain group, with a mean VOR of 0.66 (SD=0.22), was not significantly different.

LIMITATIONS

Measuring eye movements while the participant is sitting on a rotating chair in complete darkness is technically complicated.

CONCLUSIONS

This study suggests that people with nonspecific neck pain have an increased COR. The COR is an objective, nonvoluntary eye reflex and an unaltered VOR. This study shows that an increased COR is not restricted to patients with traumatic neck pain.

Disc height loss and restoration via injectable hydrogel influences adjacent segment mechanics in-vitro

BACKGROUND

Height loss can have a profound influence on the local mechanical environment of the disc. While disc height loss is incorporated into scales of degeneration, its direct influence on spine kinematics is unclear. Further, there is a need for minimally invasive techniques to restore disc height; injectable hydrogels are a potential solution. Tandem investigation of disc height loss and subsequent restoration will enhance understanding of spine dysfunction and aberrant movement.

METHODS

Twenty porcine spine specimens with two functional segments were tested in repeated flexion and extension. Relative angular displacement of each segment was measured with full specimen disc height, disc height loss in one of the segments (superior or inferior), and disc height restoration via hydrogel injection.

FINDINGS

Disc height loss decreased the range of motion at the affected segment and increased the range of motion at the adjacent segment. Relative angular displacement decreased at the affected segment by 13.8% (SD=5.3%) and 4.5% (SD=2.1%) for specimens with height loss in the superior and inferior discs respectively. Hydrogel injection was able to restore segmental kinematics to the pre-injury state, with 12.7% (SD=5.5%) and 6.4% (SD=4.2%) of motion regained at the affected segment for superior and inferior disc height loss specimens respectively.

INTERPRETATION

Acute disc height loss reduces motion at an affected segment, while increasing motion at an adjacent segment in-vitro; relative motion appears to be governed by local stiffness. Injectable hydrogels show promise in their ability to restore kinematics to segments with disc height loss.

Evaluating the neck joint position sense error with a standard computer and a webcam

Joint Position Sense Error (JPSE) is a measure of cervical spine proprioception, and a simple method for measuring the JPSE could help in monitoring and evaluating the outcomes of rehabilitation of people with neck pain. In this study we demonstrate preliminary results of a method for measuring JPSE that does not require the participant to wear any equipment. Based on free publicly available head tracking software, compatible with any webcam, we developed a webpage which instructs the participant in performing a self-administered version of the test. The aim of this proof-of-concept study was to demonstrate the viability of this system. We compared our absolute error values (3.68 ± 1.2° after extension, 3.46 ± 1.66° after flexion, 3.89 ± 2.34° after rotation to the left and 4.02 ± 1.82°after rotation to the right) to values from literature, finding that our results do not differ from those of 6 out of 11 studies (which used more complex and expensive setups). The results indicate that our system allows assessment of the JPSE with a standard computer. Being based on a website, the system has potential for telemedicine use. Further research is required to validate the system before it can be recommended for use in clinical practice.