Pupillometric parameters of alertness during unpredictable but not predictable smooth pursuit neck torsion test are altered in patients with neck pain disorders: a cross-sectional study.

Despite commonly investigated predictable smooth-pursuit neck-torsion tasks (SPNT) in neck pain patients, unpredictable conditions have been seldom investigated but are indicative of preserved oculomotor functions during neck torsion. Although not previously studied, some speculations about compensatory cognitive mechanisms such as increased phasic alertness during unpredictable tasks were suggested. The aim of this study was to investigate eye movement accuracy and pupillometric responses during predictable and unpredictable SPNT test in neck pain patients and asymptomatic controls. Eye movements (gain and SPNT-difference) and pupillometry indicative of tonic (average and relative pupil diameter) and phasic (index of cognitive activity-ICA) alertness were measured in 28 idiopathic neck pain patients and 30 asymptomatic individuals using infrared video-oculography during predictable and unpredictable SPNT test. Gain in unpredictable SPNT test was lower as compared to predictable tasks and presented with similar levels in neutral and neck torsion positions, but not in the predictable SPNT test. ICA was lower during neutral position in all tasks in patients as compared to control group but increased during neck torsion positions in unpredictable tasks. Relative pupil diameters presented with no differences between the groups or neck positions, but the opposite was observed for average pupil diameter. Higher ICA indicates an increase in phasic alertness in neck pain patients despite no alterations in oculomotor control during SPNT test. This is the first study to indicate cognitive deficits in oculomotor task in neck pain patients. The latter could negatively affect other tasks where additional cognitive resources must be involved.

The influence of neck torsion and sequence of cycles on intra-trial reliability of smooth pursuit eye movement test in patients with neck pain disorders.

The sensory mismatch commonly observed in patients with neck pain disorders could alter intra-trial reliability in simple implicit smooth pursuit eye movement tasks. This could be more pronounced when neck is in torsioned position (SPNT). The aim of this study was to explore the effects of neck torsion, target movement velocity and amplitude on intra-trial reliability of smooth pursuit eye movements in patients with neck pain disorders and healthy individuals. SPNT test was evaluated in 32 chronic neck pain patients and 32 healthy controls. Ten cycles were performed using video-oculography at three different velocities (20° s-1, 30° s-1 and 40° s-1) and at three different amplitudes (30°, 40° and 50°) of target movement. Intra-trial reliability and differences between average gain and SPNT difference from the second to fifth cycle and from the sixth to ninth cycle were assessed using ICC3.1 and factorial analysis of variance, respectively. Intra-trial reliability for gain and SPNT difference at all target movement amplitudes and velocities proved to be good to excellent in both observed groups. Patients with neck pain disorders presented with a trend of inferior gain performance between the sixth and ninth cycle at 30° s-1 of target movement as compared to healthy individuals which was only evident when neck was in torsioned position. Although intra-trial reliability of smooth pursuit neck torsion test is good to excellent, the effects of learning are not as pronounced in patients with neck pain disorders.

Pathophysiology behind prolonged whiplash associated disorders: study protocol for an experimental study.

BACKGROUND: There is insufficient knowledge of pathophysiological parameters to understand the mechanism behind prolonged whiplash associated disorders (WAD), and it is not known whether or not changes can be restored by rehabilitation. The aims of the projects are to investigate imaging and molecular biomarkers, cervical kinaesthesia, postural sway and the association with pain, disability and other outcomes in individuals with longstanding WAD, before and after a neck-specific exercise intervention. Another aim is to compare individuals with WAD with healthy controls. METHODS: Participants are a sub-group (n = 30) of individuals recruited from an ongoing randomized controlled study (RCT). Measurements in this experimental prospective study will be carried out at baseline (before intervention) and at a three month follow-up (end of physiotherapy intervention), and will include muscle structure and inflammation using magnetic resonance imaging (MRI), brain structure and function related to pain using functional MRI (fMRI), muscle function using ultrasonography, biomarkers using samples of blood and saliva, cervical kinaesthesia using the "butterfly test" and static balance test using an iPhone app. Association with other measures (self-reported and clinical measures) obtained in the RCT (e.g. background data, pain, disability, satisfaction with care, work ability, quality of life) may be investigated. Healthy volunteers matched for age and gender will be recruited as controls (n = 30). DISCUSSION: The study results may contribute to the development of improved diagnostics and improved rehabilitation methods for WAD. TRIAL REGISTRATION: Clinicaltrial.gov Protocol ID: NCT03664934, initial release 09/11/2018.

How well can we detect cervical driven sensorimotor dysfunction in concussion patients? An observational study comparing patients with idiopathic neck pain, whiplash associated disorders and concussion.

BACKGROUND: Patients with mild traumatic brain injury (mTBI) suffer from sensorimotor impairments. Evidence is emerging that cervical spine plays an important role in mTBI, but it is not known how cervicocephalic kinaesthetic sensibility measured during dynamic unpredictable head movements and measures of position sense, cervical induced postural balance and eye movement control differ between mTBI, whiplash associated disorders (WAD) patients, idiopathic neck pain patients and healthy controls. RESEARCH QUESTION: Are cervical sensorimotor deficits present in mTBI patients and do they differ from sensorimotor deficits found in traumatic and nontraumatic neck pain patients and whether they differ from healthy controls. METHODS: Twenty idiopathic neck pain patients, 18 WAD, 17 mTBI and 20 healthy controls were enroled in the study. Frequency and velocity of centre of pressure movements were measured during parallel stance in the neutral and neck torsion positions, gain and smooth pursuit neck torsion difference of eye movements during smooth pursuit neck torsion test (SPNTT) and cervicocephalic kinaesthesia using Butterfly and head-to-neutral relocation test. RESULTS: Statistically significant differences in postural balance, both tests of cervicocephalic kinaesthesia and SPNTT were observed between healthy controls and all patient groups. No differences were observed between patient groups for SPNTT, Butterfly and head-to-neutral relocation test, but differences were present in postural balance between mTBI and both groups of patients with neck pain disorders. Differences were found in the ML direction for mTBI, but not differences were found for AP direction. SIGNIFICANCE: Results of our study show that mTBI present with similar impairment in cervical driven sensorimotor deficits as patients with neck pain disorders, but they differ from healthy individuals. Clinical practice would benefit from identifying cervical spine related sensorimotor impairments in patients with mTBI. This could enable to design more targeted prevention and rehabilitation programs to minimise cervical spine related disorders in concussion patients.

Oculomotor performance in patients with neck pain: Does it matter which angle of neck torsion is used in smooth pursuit eye movement test and is the agreement between angles dependent on target movement amplitude and velocity?

BACKGROUND: Neck torsion manoeuvre is thought to affect eye movement control via afferent sensory drive in neck pain disorders patients. Literature reports inconsistencies regarding the angle of neck torsion most commonly used across the studies. OBJECTIVES: The goal of this study was to determine the level of agreement in oculomotor performance between two most commonly used neck torsion angles during smooth pursuit neck torsion test (SPNT). DESIGN: A cross-sectional design was used in thirty-two neck pain patients and thirty-two healthy individuals. METHOD: Gain and SPNTdiff were measured during SPNT test at 30° and 45° of neck torsion angle, at 30°, 40° and 50° of target movement amplitudes and three different target movement velocities (20°s-1, 30°s-1 and 40°s-1) using eye tracking device. Bland-Altman plots and correlation analysis were used to study the agreement between the two angles. RESULTS: Small to medium correlations and wide bias confidence intervals suggest medium level of agreement in gain or SPNTdiff between the two neck torsion angles for chronic neck pain patients, but higher in healthy individuals. Higher agreement in gain was observed at lager target movement amplitudes and at slower target movement velocities, however this trend was not observed for SPNTdiff. CONCLUSION: Level of agreement between the two angles in SPNT test depends on the amplitude and velocity of the moving target. In cases when subjects within the same study are not able to perform 45° of neck torsion, 50° amplitude and 20°s-1 velocity of target movement are more suitable to reach higher agreement between the angles.

Is Altered Oculomotor Control during Smooth Pursuit Neck Torsion Test Related to Subjective Visual Complaints in Patients with Neck Pain Disorders?

Subjective visual complaints are commonly reported in patients with neck pain, but their relation to objectively measured oculomotor functions during smooth pursuit neck torsion tests (SPNTs) has not yet been investigated. The aim of the study was to analyse classification accuracy of visual symptom intensity and frequency based on SPNT results. Forty-three patients with neck pain were referred by orthopaedic outpatient clinics where they were required to fill out 16-item proformas of visual complaints. Infrared video-oculography was used to measure smooth pursuit eye movements during neutral and neck torsion positions. Parameters of gain and SPNT difference (SPNTdiff) were taken into the Naïve Bayes model as classifiers, while intensity and frequency of visual symptoms were taken as predicted class. Intensity and, to a lesser degree, frequency of visual symptoms previously associated with neck pain or focal vision disorders (computer vision syndrome) showed better classification accuracy using gain at neck torsion position, indicating cervical driven visual disturbances. Moreover, SPNTdiff presented with slightly lower classification accuracy as compared to gain at neck torsion position. Our study confirmed the relationship between cervical driven oculomotor deficits and some visual complaints (concentrating to read, words moving on page, blurred vision, difficulty judging distance, sore eyes, heavy eyes, red eyes, and eyes strain).

Relationship between Cervicocephalic Kinesthetic Sensibility Measured during Dynamic Unpredictable Head Movements and Eye Movement Control or Postural Balance in Neck Pain Patients.

Cervical afferent input is believed to affect postural balance and oculomotor control in neck pain patients, but its relationship to cervicocephalic kinesthesia, describing movement sense, has not yet been studied. The aim of this study was to analyze the relationship of two aspects of cervicocephalic kinesthesia to postural balance and oculomotor control in neck torsion positions. Forty-three idiopathic neck pain patients referred from orthopedic outpatient clinics and forty-two asymptomatic controls were enrolled in the study. A force plate was used to measure center-of-pressure movements during parallel stances under neutral and neck torsion maneuvers. Video-oculography was used to assess eye movements during smooth pursuit neck torsion test (SPNTT), while kinesthetic awareness was measured using the Butterfly test and head-to-neutral relocation test. Multiple regression was used to describe relationships between tests. Body sway in the anterior-posterior direction was related to Butterfly parameters but less to the head-to-neutral test. A medium relationship between Butterfly parameters and gain during SPNTT, with less SPNT-difference, was observed, but not for the head-to-neutral test. It can be concluded that specific aspect of neck kinesthetic functions (i.e., movement sense) importantly contributes towards oculomotor and balance control, which is more evident under neck torsion positions in neck pain patients, but is less pronounced in asymptomatic individuals.

Video-oculographic measures of eye movement control in the smooth pursuit neck torsion test can classify idiopathic neck pain patients from healthy individuals: A datamining based diagnostic accuracy study.

BACKGROUND: Idiopathic neck pain patients frequently experience oculomotor disfunctions with deficits in eye movement control between neutral and neck torsion position (SPNT test) being commonly investigated in clinical and research settings. OBJECTIVES: The aim of the study was to determine accuracy of SPNT test in classifying idiopathic neck pain patients. DESIGN: a datamining based diagnostic accuracy study. METHODS: The study was conducted on a referred sample of 38 chronic neck pain patients from orthopaedic outpatient clinic and 40 healthy controls. Video-oculography was used to study gain and SPNTdiff during SPNT test under three target movement velocities and amplitudes and two different angles of neck torsion. A Naïve Bayesian predictive model was used to classify neck pain patients based on gain or SPNTdiff. RESULTS: Gain during two target movement profiles at velocities of 30°s-1 and amplitudes of 30° and 40° under 45° of neck torsion presented with highest area under the curve (0.837), specificity (92%), sensitivity (94%), highest true positive and lowest false negative predicted value. Highest area under the curve (0.760), specificity (50%), sensitivity (71%), highest true positive and lowest false negative values were observed for SPNTdiff at velocities of 30°s-1 and amplitude of 30° applying 45° of neck torsion. CONCLUSION: SPNT test provides useful diagnostic tool for classifying neck pain patients when using single or combination of two target movement profiles. Neck torsion of 45° as opposed to 30° should be used during SPNT test when investigating patients with neck pain disorders.

Inter-Visit Reliability of Smooth Pursuit Neck Torsion Test in Patients with Chronic Neck Pain and Healthy Individuals.

Visual disturbances are commonly reported in patients with neck pain. Smooth pursuit neck torsion (SPNT) test performed in neutral position and with trunk rotated under the stationary head has been used to discriminate between those with cervical component and those without. However, no studies investigated the reliability of the SPNT-test in patients with chronic neck pain and healthy controls. The aim of this study was to assess inter-visit reliability of the SPNT-test while applying different amplitudes and velocities of target movement. Thirty-two controls and thirty-one patients were enrolled in the study. The SPNT-test was performed in neutral position and through 45° torsion positions. The test was performed at 20°/s, 30°/s and 40°/s velocities and at 30°, 40° and 50° amplitudes of cyclic sinusoidal target movements. Interclass correlation coefficient and smallest detectable change were calculated for parameters of gain and SPNT-differences. In patients, moderate to good reliability was observed for gain at 40° and 50° amplitudes and for 20°/s and 30°/s velocities, while moderate to excellent reliability for gain was observed in controls. Both groups presented with moderate to good reliability for SPNT-difference. Our findings imply that amplitudes of 40° and 50° and velocities of 20°/s and 30°/s are the most reliable and should be applied in future studies assessing oculomotor functions during the SPNT test.

Postural balance and oculomotor control are influenced by neck kinaesthetic functions in elite ice hockey players.

BACKGROUND: Research indicates that neck kinaesthetic awareness plays an important role in oculomotor and balance control, however the relationship has not been studied in athletes. As performance in ice hockey demands visual perception acuity during skating, while constantly shifting between unilateral and bilateral stances in sports specific posture more in-depth relationship should be studied. RESEARCH QUESTION: What is the relationship between neck kinaesthetic awareness, postural balance and eye movement control in professional ice hockey players and non-trained individuals? METHODS: In this observational study, centre-of-pressure was measured using force plate in twenty-eight hockey players and thirty non-trained participants during different stances in eyes-opened and eyes-closed conditions. Butterfly test and Head-to-Neutral Relocation test were performed to assess neck kinaesthesia. Horizontal smooth pursuit eye movements were measured using video-oculography. Linear regression was used to determine the relationship between neck kinaesthesia, body sway and oculomotor control. RESULTS: Time-on-target in Butterfly test was able to predict low to medium proportions of variance in amplitude and velocity parameters for single leg stances in hockey players (R2 = .220-.698). Head-to-Neutral Relocation test was able to predict low to medium proportion of variance in average eye movement velocity during first 100 milliseconds of smooth pursuit initiation for both groups (R2 = .262-.541). SIGNIFICANCE: Findings from our study suggest that cervical spine afferent input plays an important role in maintaining unilateral postural balance in hockey players, with less evidence presented in controls. Sports specific posture or upper body loading could lead to adaptations in neck proprioception, not frequently considered when searching for balance related injury risk factors or performance deficits. Our study suggests, that in addition to balance control, neck kinaesthesia can also affect oculomotor performance which was present in both groups. This is especially evident when initiating changes in eye movement direction.

Altered scapular orientation during arm elevation in patients with insidious onset neck pain and whiplash-associated disorder.

STUDY DESIGN: Controlled laboratory study using a cross-sectional design. OBJECTIVES: To investigate whether there is a pattern of altered scapular orientation during arm elevation in patients with insidious onset neck pain (IONP) and whiplash-associated disorder (WAD) compared to asymptomatic people. BACKGROUND: Altered activity in the axioscapular muscles and impairments in scapular orientation are considered to be important features in patients with cervical disorders. Scapular orientation has until now not been investigated in these patients. METHODS: A 3-dimensional tracking device measured scapular orientation during arm elevation in patients with IONP (n = 21) and WAD (n = 23). An asymptomatic group was selected for comparison (n = 20). RESULTS: The groups demonstrated a significantly reduced clavicle retraction on the dominant side compared to the nondominant side. The WAD group demonstrated an increased elevation of the clavicle compared to the asymptomatic group and the IONP group, and reduced scapular posterior tilt on the nondominant side compared to the IONP group. CONCLUSION: Altered dynamic stability of the scapula may be present in patients with cervical disorders, which may be an important mechanism for maintenance of recurrence or exacerbation of symptoms in these patients. Patients with cervical disorders may demonstrate a difference in impairments, based on their diagnosis of IONP or WAD.

Sensorimotor function and dizziness in neck pain: implications for assessment and management.

SYNOPSIS: The term sensorimotor describes all the afferent, efferent, and central integration and processing components involved in maintaining stability in the postural control system through intrinsic motor-control properties. The scope of this paper is to highlight the sensorimotor deficits that can arise from altered cervical afferent input. From a clinical orthopaedic perspective, the peripheral mechanoreceptors are the most important in functional joint stability; but in the cervical region they are also important for postural stability, as well as head and eye movement control. Consequently, conventional musculoskeletal intervention approaches may be sufficient only for patients with neck pain and minimal sensorimotor proprioceptive disturbances. Clinical experience and research indicates that significant sensorimotor cervical proprioceptive disturbances might be an important factor in the maintenance, recurrence, or progression of various symptoms in some patients with neck pain. In these cases, more specific and novel treatment methods are needed which progressively address neck position and movement sense, as well as cervicogenic oculomotor disturbances, postural stability, and cervicogenic dizziness. In this commentary we review the most relevant theoretical and practical knowledge on this matter and implications for clinical assessment and management, and we propose future directions for research. LEVEL OF EVIDENCE: Level 5.

Women with late whiplash syndrome have greatly reduced load-bearing of the cervical spine. In-vivo biomechanical, cross-sectional, lateral radiographic study.

BACKGROUND: No study has been conducted to ascertain whether the load-bearing capacity of the cervical spine is reduced in vivo in late whiplash syndrome (LWS). AIM: To compare the segmental cervical angular values across C0-C6, between two conditions: without versus with external axial load upon the head in three groups of women. DESIGN: A single-blind, age-Body Mass Index (BMI) matched, radiographic, cross-sectional study. SETTING: Radiographic Department at a University Hospital. POPULATION: One hundred eighty-two women, aged between 18-50 years were enrolled. METHODS: Participants were divided into 3 groups: a group with LWS (N.=62) and two control groups: a chronic insidious neck pain (IONP) group (N.=60) and an asymptomatic group (N.=60). Prior to and on the same day as the radiographic examination took place, BMI in kg/m2 was recorded and all participants answered the Neck Disability Index (NDI). The two symptomatic groups answered also three other pain and disability questionnaires. RESULTS: Analysis of variance (mixed-model ANOVA) for repeated measures was used for comparison. Significant differences between groups, and the two conditions tested was revealed, but only within the asymptomatic and the IONP groups (P<0.0001), but not within the LWS group (P=0.9433). Unexpectedly the women with LWS adopted a rigid horizontal translation strategy when external load was applied upon their head. The inter-rater and intra-rater segmental measurements were highly reliable. Women with LWS scored significantly higher on all questionnaires. CONCLUSIONS: The results of this study strongly indicate that the load-bearing capacity of the cervical spine is reduced in vivo in women with LWS. The study shows, for the first time, that the cervical spine in women with LWS predominately functions such as a rigid cylinder when loaded. CLINICAL REHABILITATION IMPACT: The study implies that the cervical column is extremely weak in the LWS and that the superficial neck muscles, which are designed to move the head-neck, must compensate and act as rigid stabilizers. This causes great joint reaction forces through the cervical spine and its injured inert structures maintaining the pain and disability, as the results of the questionnaires show.

The long-term course of deficient cervical kinaesthesia following a whiplash injury has a tendency to seek a physiological homeostasis. A prospective study.

BACKGROUND: No research exists for the long-term course of deficient cervical kinaesthesia following a whiplash injury. Prior results depicted two divergent courses of deficient cervical kinaesthesia at 1 year. OBJECTIVES: First, to determine the actual course(s) of untreated deficient cervical kinaesthesia from 1 year to 6-8 years post-collision and second, to investigate the association between the test results versus self-reported disability. DESIGN: A follow-up study was conducted to measure persons who had experienced whiplash from January 2007-September 2009. METHOD: The two clinical tests for cervical kinaesthesia, the Head-Neck Relocation (HNR) test and the Fly test are conceptualised to measure two distinct "percepts" of neck proprioception: position sense and movement sense, respectively. In both tests, the mean error of three trials was calculated for each individual and represented the kinaesthetic accuracy. These values were used for analysis. RESULTS: Forty-one participants out of an initial forty-seven (response rate = 87.2%) were able to participate at the 6-8 years follow-up. The two divergent courses at 12 months had a tendency to seek a physiological homeostasis at the 6-8 years follow-up. Overall, very slight improvements were revealed in disability levels between the 2 assessment points. CONCLUSIONS: Untreated deficient cervical kinaesthesia has a tendency to seek a physiological homeostasis somewhere from 1 year to 6-8 years post-collision. We therefore recommend that cervical kinaesthesia be monitored and treated early, as deficient cervical kinaesthesia may lead to adaptive compensatory patterns secondary to the remaining functional kinaesthetic deficits.

Sincerity of effort versus feigned movement control of the cervical spine in patients with whiplash-associated disorders and asymptomatic persons: a case-control study.

STUDY DESIGN: Cross-sectional design. OBJECTIVES: To investigate whether the Fly Test can be used to differentiate patients with whiplash-associated disorders (WAD) from asymptomatic persons who deliberately feign symptoms and from WAD patients exaggerating symptoms. BACKGROUND: The lack of valid clinical tests makes it difficult to detect a justifiable cause for compensation claims in traumatic neck-pain disorders. METHODS: The Fly Test recorded the accuracy of neck movements in patients with WAD (n = 34) and asymptomatic persons (n = 31). The participants followed a moving "Fly" on a computer screen with a cursor from sensors mounted on the head. Two conditions were tested, sincere versus feigned efforts. In the former, the participants moved their neck as accurately as possible. In the latter, a short text was presented describing a fictitious accident (asymptomatic group) or imagining more intense pain/suffering (WAD group), and the test was performed as affected by these more serious conditions. Amplitude accuracy (AA), time on target (ToT) and jerk index (JI) were compared across patterns, conditions and groups. RESULTS: The sincere effort in the WAD group was significant compared to the feigned effort of the asymptomatic group (p < 0.001). For AA, correct categorization of 81.5% of the performances was made, where a mean score above 5.5 mm differentiated feigned versus sincere efforts in asymptomatic and WAD groups (sensitivity 79.4%, specificity 67.7%). For ToT, score above 11% indicated correctly categorized WAD patients (sensitivity 82.4%, specificity 64.5%). CONCLUSION: The Fly Test can provide clinicians a clue when patients with mild to moderate pain/disability are feigning or exaggerating symptoms.

Reliability of ultrasonography for the cervical multifidus muscle in asymptomatic and symptomatic subjects.

A test-retest and inter-tester study was designed to assess the reliability of ultrasonography to depict the size of the cervical multifidus muscle in asymptomatic and symptomatic subjects. Ten asymptomatic women (range 19-48 years) and 10 women with chronic whiplash associated disorder (WAD), grade II, (range 19-49 years), matched for height and weight participated. The women were imaged by ultrasonography on two separate occasions by two different testers. On each occasion the cross-sectional area (CSA), and the transverse versus the anterior-posterior dimensions (shape ratio) at the C4 level were measured. The repeated measurements of the CSA were plotted against their means to reveal the limit of agreement. Good agreement was found for the asymptomatic group measurements and the intra-tester agreement for the symptomatic group. The inter-tester agreement for the symptomatic group was questionable. The size of the multifidus muscle was significantly reduced in the symptomatic group ( P<0.05 ). The results indicate that loss of clarity of the fascial layer between the semispinalis cervicis muscle and the cervical multifidus muscle may be a diagnostic sign of muscle atrophy. Ultrasonography can be used to precisely measure the size of the cervical multifidus muscle at the C4-level in asymptomatic young female subjects; it is also reliable for symptomatic subjects if the same tester performs the measurements. Additional criteria are recommended to improve the inter-tester agreement for symptomatic subjects.

Database of movement control in the cervical spine. Reference normal of 182 asymptomatic persons.

In this study, the first normative database of movement control in the cervical spine has been established. For this purpose the Fly Test was used, which is a reliable and valid clinical test capable of detecting deficient movement control of the cervical spine in patients with neck pain and its associated disorders. One hundred and eighty-two asymptomatic persons, eighty-three men and ninety-nine women, aged 16-74 years, divided into six age groups, were recruited. The Fly Test, using a 3-space Fastrak device, recorded the accuracy of cervical spine movements when tracking three incrementally difficult movement patterns. Amplitude accuracy (AA), directional accuracy (DA), and jerk index (JI) were compared across patterns and age groups. A multivariate analysis of variance revealed a significant effect for age (p < 0.001) but not gender (p > 0.05). Lower accuracy for AA and DA in all three movement patterns was observed in the groups of subjects aged 55-64 and 65-74 years, and also for JI in the easy and medium patterns. Knowledge of normative values for the Fly Test is important and useful in identifying impaired movement control and monitoring the effectiveness of treatment interventions in patients with neck pain of traumatic and non-traumatic origin.

Two different courses of impaired cervical kinaesthesia following a whiplash injury. A one-year prospective study.

A longitudinal study was conducted to observe persons with neck pain after motor vehicle collisions. The aims were to reveal the prospective development of cervical kinaesthesia and to investigate the association between the test results and self-reported pain and disabilities. Two different cervical kinaesthetic tests, the Fly test and the Head-Neck Relocation test, measured movement control and the relocation accuracy of the cervical spine, respectively. Self-assessment measures included pain intensity (VAS), neck pain and disability (NDI), fear of re-injury (TAMPA) and psychological distress (GHQ-28). Seventy-four subjects entered the study, but 47 were eligible, as they participated in all 4 measurements at 1, 3, 6 and 12 months post-collision. According to the performances on the two kinaesthetic tests, the subjects could be classified into improvement and non-improvement groups, respectively. The result revealed, for the first time, two different courses of deficient cervical kinaesthesia. About half of the participants showed significant deteriorating performances in both kinaesthetic tests throughout the year (p < 0.002), while the other half improved their performances (p < 0.02). Generally, the relationships between the kinaesthetic tests and the self-assessment scores were not significant, irrespective of the performances on the two kinaesthetic tests. Accordingly, the results of the questionnaires correlated poorly or weakly with the kinaesthetic test results at all assessment points. The need for developing a new questionnaire, capturing the symptoms prevalent in patients with neck pain and cervical sensorimotor impairments is urgent. What determines the two different kinaesthetic courses need to be scrutinised in future research.

Assessment and validation of prognostic models for poor functional recovery 12 months after whiplash injury: a multicentre inception cohort study.

Uncertainty surrounds prognostic factors after whiplash injury. Previously we identified a prognostic model for 6-month pain-related disability in a cohort of 80 participants with acute whiplash. Predictors included initial disability, older age, decreased cold pain thresholds, decreased neck rotation movement, posttraumatic stress symptoms and decreased sympathetic vasoconstriction. The objective of this study was to externally validate this model. In a multicentre inception cohort study, 286 participants with acute whiplash (I, II or III) were assessed at <3 weeks and 12 months after injury. The Neck Disability Index (NDI) was the outcome. Observed and predicted NDI scores were generated using the published equation of the original model. Model discrimination between participants with no or mild disability from those with moderate to severe disability was examined by receiver operating characteristic curves. Initial NDI and cold pain threshold predicted current observed 12-month NDI scores (r(2) = 0.50, 95% confidence interval 0.42 to 0.58). There was a significant site effect, and the estimated marginal mean ± SE of 12-month NDI for Iceland (27.6 ± 1.79%) was higher than the other 3 sites (Melbourne 11.2 ± 5.03%, Canada 16.4 ± 2.36%, Brisbane 16.8 ± 1.17%). After adjusting for site, age and Impact of Events Scale scores regained significance (r(2) = 0.56, 95% confidence interval 0.48 to 0.64). The tested model was not precise in predicting NDI as a continuous variable. However, it found good accuracy to discriminate participants with moderate to severe disability at 12 months (area under the receiver operating characteristic curve 0.89 [95% confidence interval 0.84-0.94], P<.001) which is clinically useful.

Altered alignment of the shoulder girdle and cervical spine in patients with insidious onset neck pain and whiplash-associated disorder.

Clinical theory suggests that altered alignment of the shoulder girdle has the potential to create or sustain symptomatic mechanical dysfunction in the cervical and thoracic spine. The alignment of the shoulder girdle is described by two clavicle rotations, i.e, elevation and retraction, and by three scapular rotations, i.e., upward rotation, internal rotation, and anterior tilt. Elevation and retraction have until now been assessed only in patients with neck pain. The aim of the study was to determine whether there is a pattern of altered alignment of the shoulder girdle and the cervical and thoracic spine in patients with neck pain. A three-dimensional device measured clavicle and scapular orientation, and cervical and thoracic alignment in patients with insidious onset neck pain (IONP) and whiplash-associated disorder (WAD). An asymptomatic control group was selected for baseline measurements. The symptomatic groups revealed a significantly reduced clavicle retraction and scapular upward rotation as well as decreased cranial angle. A difference was found between the symptomatic groups on the left side, whereas the WAD group revealed an increased scapular anterior tilt and the IONP group a decreased clavicle elevation. These changes may be an important mechanism for maintenance and recurrence or exacerbation of symptoms in patients with neck pain.