Upper cervical range of motion is impaired in patients with temporomandibular disorders

Comparison of Machine Learning Algorithms Fed with Mobility-Related and Baropodometric Measurements to Identify Temporomandibular Disorders

Temporomandibular disorders (TMDs) refer to a group of conditions that affect the temporomandibular joint, causing pain and dysfunction in the jaw joint and related muscles. The diagnosis of TMDs typically involves clinical assessment through operator-based physical examination, a self-reported questionnaire and imaging studies. To objectivize the measurement of TMD, this study aims at investigating the feasibility of using machine-learning algorithms fed with data gathered from low-cost and portable instruments to identify the presence of TMD in adult subjects. Through this aim, the experimental protocol involved fifty participants, equally distributed between TMD and healthy subjects, acting as a control group. The diagnosis of TMD was performed by a skilled operator through the typical clinical scale. Participants underwent a baropodometric analysis by using a pressure matrix and the evaluation of the cervical mobility through inertial sensors. Nine machine-learning algorithms belonging to support vector machine, k-nearest neighbours and decision tree algorithms were compared. The k-nearest neighbours algorithm based on cosine distance was found to be the best performing, achieving performances of 0.94, 0.94 and 0.08 for the accuracy, F1-score and G-index, respectively. These findings open the possibility of using such methodology to support the diagnosis of TMDs in clinical environments.

The effectiveness of cervical rehabilitation interventions for pain in adults with myogenic temporomandibular disorders: A systematic review and meta-analysis

OBJECTIVE

Little evidence exists for the most effective conservative treatment approach for adults with myogenic temporomandibular disorders (MTMD). We aim to assess the effectiveness of cervical rehabilitation interventions on pain intensity and sensitivity in adults with MTMD compared to comparison intervention such as placebo, sham treatment, education or no intervention.

METHODS

For this systematic review and meta-analysis, we searched PubMed, EMBASE, Medline, PEDro databases, forward and backward citations and grey literature studies through PROSPERO, clinical trials and data registries without language or date restrictions between inception and 1 December 2021. We selected randomised controlled trials (RCTs) based on adult populations with MTMD who had a cervical rehabilitation intervention which was defined as any conservative intervention targeting the anatomical structures of the cervical spine. The primary outcome measures for pain were self-reported pain intensity and pain sensitivity through the pressure pain threshold (PPT) of the masseter and temporalis muscles. Secondary outcome measures of maximal mouth opening (on MMO) were included. Included studies were assessed for bias with the Cochrane risk of bias tool for randomised trials. Evidence from RCTs was synthesised to determine treatment effect size as differences between standardised mean difference (SMD) for changes in pain intensity, PPT and MMO comparing adults with MTMD who were treated with cervical rehabilitation interventions compared to a control group. This study is registered on Prospero, number CRD 42021289299.

RESULTS

Our general search yielded 2647 studies where seven RCTs met eligibility criteria with low to some concerns in their risk of bias. Pain intensity (five studies, n = 223, SMD -0.98, 95% CI -1.67 to -0.28, I2 = 79%), PPT of the masseter muscle (six studies, n = 395, SMD 0.64, 95% CI 0.43 to 0.86, I2 = 90%) and the temporalis muscles (five studies, n = 295, SMD 0.76, 95% CI 0.07 to 1.45, I2 = 84%) showed large treatment effect estimates favouring cervical rehabilitation interventions compared to no treatment, sham cervical treatment, patient education or non-cervical neuromuscular techniques. Compared to control interventions, one type of cervical rehabilitation intervention, cervical manual therapy alone or in combination with a neck exercise program was associated with statistically significant, large treatment effect estimates on pain intensity (four studies, n = 203, SMD -1.52, 95% CI -2.50 to -0.55).

CONCLUSIONS

This review found that in the short-term, cervical rehabilitation interventions especially upper cervical MT alone or in combination with a neck exercise program are effective in improving multiple pain outcomes in adults with MTMD. However, further research is needed to measure the long-term effects of this type of intervention.

Evaluation of the effect of different kinds of treatment modalities for temporomandibular joint pain and its relevance to chronic cervical pain: A randomized controlled trial

AIM

The aim of this study was to evaluate the effect of different treatment modalities for temporomandibular joint (TMJ) pain and their relevance to chronic cervical pain after 12 months.

SETTINGS AND DESIGN

This was a randomized controlled trial.

MATERIALS AND METHODS

Forty-eight participants with chronic cervical and TMJ pain were selected using research diagnostic criteria and randomized into four groups (n = 12), which included control, soft splints, transcutaneous electrical nerve stimulation (TENS), and low-level laser (LLL). The cervical and TMJ pain was recorded using visual analog scale (VAS) scores at baseline, 3 months, 6 months, and 12 months. Occlusal equilibration was done for all groups except for the control.

STATISTICAL ANALYSIS USED

The mean pain scores were statistically analyzed using one-way analysis of variance and posthoc test.

RESULTS

The mean VAS scores in TMJ pain patients between the four groups at baseline and at final follow-up were 7.27 ± 1.29 in Group 1, 7.53 ± 0.70 in Group 2, 7.76 ± 0.80 in Group 3, and 7.61 ± 0.61 in Group 4. The mean difference between Groups 1 and 3, Groups 1 and 4, and Groups 2 and 3 was statistically significant (P < 0.00). Pearson correlation test yielded a mild and negative correlation between TMJ and cervical pain.

CONCLUSION

TENS and LLL were found to be equally effective in reducing pain in the jaw joint region, followed by soft splints, and there was no correlation between TMJ and cervical pain.

Efficacy of a strength-based exercise program in patients with chronic tension type headache: a randomized controlled trial

Background

Strength-based exercise is widely used to treat tension-type headache, but the evidence of its benefit is unclear. This study aims to analyze the efficacy of a strength-based exercise program in patients with chronic tension-type headaches.

Methods

A randomized controlled trial with a 12-week strength-based exercise program, with chronic tension-type headache. The headache characteristics (which were the primary outcomes: frequency, duration, and intensity), cervical muscle thickness at rest or contraction of multifidus and longus-colli muscle, cervical range of motion, pain pressure threshold of temporalis, upper trapezius, masseter, tibialis muscle and median nerve, and cervical craniocervical flexion test were assessed at baseline and 12-weeks of follow-up in the intervention group (n = 20) and the control group (n = 20) was performed on 40 patients (85% women, aged 37.0 ± 13.3 years).

Results

Between baseline and week-12 of follow-up the intervention group showed statistically significant differences compared to control group in the following primary outcomes: duration and intensity of headaches. In addition, the intervention group improved the thickness of deep cervical muscles, reduced the peripheral sensitization, and improved the strength of deep cervical flexors.

Conclusion

A 12-week strength training of neck and shoulder region induced changes in pain intensity and duration, and physical-related factors in patients with TTH. Future interventions are needed to investigate if normalization of pain characteristics and physical factors can lead to an increase of headache-related impact.

Evaluation and management of temporomandibular disorders. Part 2: an orthopaedic physical therapy update on examination and clinical reasoning

Temporomandibular (TM) disorders afflict many people globally and, despite the presence of existing peer-reviewed material that assists conservative orthopedic providers, recent advances in knowledge indicate that updated resources are required for students, clinicians, and educators. This two-part series builds off previously published material to present newer supplementary information that can be useful during the evaluation and management processes. Content in Part 1 of this series includes a discussion about the factors that have been shown to contribute to TM disorders, an updated perspective of relevant pain science, a discussion of self-report outcome measures, and various different topics related to the examination of patients with TM disorders. Part 2 addresses information related to the temporomandibular joint disc, joint hypermobility, oral splints, and clinical reasoning. In combination with other available publications, this two-part series provides clinicians an opportunity to improve their delivery of effective and efficient clinical services for people diagnosed with TM disorders.

Cervical Range of Motion Analysis Performed with an Accelerometer: A Study of Intersession Reliability for Dental Practice

During the clinical examination of subjects with temporomandibular disorders (TMDs), the dentist sometimes must evaluate the cervical spine, due to the anatomical and functional connections between the cervical portion of the spine and the stomatognathic apparatus. The accelerometer is a device that evaluates the Range of Motion (ROM) of the main movements of the head on the neck. To date, only a few studies have investigated the repeatability of the use of the accelerometer in the assessment of cervical ROM. Therefore, the present longitudinal observational study analyzed the repeatability of acquired cervical movements on a sample of volunteer subjects who underwent accelerometer testing. A sample of 32 subjects was tested twice within 14 days to assess cervical ROM using a standardized protocol based on a review of existing literature. The results show that the examination is reliable for all the positions of the jaw, except for the parameters regarding the asymmetries of rotation and bending. In conclusion, the accelerometer can be considered a reliable tool for evaluating the active cervical ROM. However, further studies will be necessary to make better evaluations.

Do Temporomandibular Disorder Patients with Joint Pain Exhibit Forward Head Posture? A Cephalometric Study

Purpose

To evaluate head and cervical posture in individuals with or without temporomandibular disorders (TMDs) and to assess the correlations between pain, severity of symptoms, and posture.

Methods

A total of 384 patients (129 males and 255 females) was included. The Fonseca Anamnestic Index (FAI) was used to assess the severity and prevalence of TMD and the presence of temporomandibular joint (TMJ) pain. Patients were divided into three groups: the TMD-free group, TMD without TMJ pain group, and TMD with TMJ pain group. Subsequently, the patients with TMJ pain were further divided into mild TMD and moderate/severe TMD groups. Nine parameters were traced on cephalograms to characterize the head and cervical posture.

Results

TMD patients with TMJ pain showed increased forward head posture (FHP) than patients without TMJ pain and TMD-free subjects. No significant difference was observed between the TMD patients without TMJ pain and TMD-free subjects. In the TMD patients with the TMJ pain group, the moderate/severe TMD patients demonstrated increased FHP compared to mild TMD patients. TMD patients with joint pain had greater CVT/RL (B = 3.099), OPT/RL (B = 2.117), and NSL/C2' (B = 4.646) than the patients without joint pain after adjusting for confounding variables (P < 0.05).

Conclusion

TMD patients with TMJ pain showed increased FHP compared to other groups, and FHP became more significant as TMD severity increased in male patients, indicating the FHP might play an important role in the development of TMJ pain. In the clinical assessment of TMD, the patients' abnormal head and cervical posture might be considered.

Temporomandibular disorder prevalence and its association with oral parafunctions, neck pain, and neck function in healthcare students: A cross-sectional study

OBJECTIVE

To determine the temporomandibular disorder (TMD) prevalence in female students and to assess its association with oral parafunctions, neck pain, and function.

METHODS

One hundred forty-four participants were included. The severity of TMD was assessed with Fonseca's Anamnestic Index (FAI). The oral parafunctions were self-reported with the Oral Behaviors Checklist (OBC). Neck pain and neck function were recorded with the Core Outcome Measure Index (COMI). The Spearman correlation analysis was used for statistical analysis.

RESULTS

Seventy participants (48.6%) had mild TMD. All participants had a positive OBC score, which indicated an oral parafunction. A moderate correlation between TMD and oral parafunctions (p < 0.001) was detected.

DISCUSSION

TMD is common in female healthcare students, and its presence is associated with oral parafunctions, neck pain, and function. It is recommended to evaluate oral health habits and neck pain and function in females with TMD.

Improvement of cervical spine mobility and stance stability by wearing a custom-made mandibular splint in male recreational athletes

OBJECTIVES

The range of motion (ROM) of the cervical spine and postural stability are important for an economical and motorically adequate adaptation of the body to any situation. Therefore, this study aims to analyze whether these two components of postural and movement control can be influenced by means of a splint in a centric position compared to habitual occlusion.

METHODS

38 recreational male athletes volunteered. Cervical spine ROM was recorded using an ultrasound system and the a pressure measuring plate for postural stability (length of center of pressure (CoP) movement, area of CoP). The two dental occlusion conditions employed were the habitual occlusion and wearing a splint in an idealized, condylar position close to the centric position. Level of significance was set at ρ ≤ 0.05.

RESULTS

The cervical spine mobility increased significantly by wearing the splint regarding rotation to the left (+3.9%) and right (+2.7%) and lateral flexion to the left (+4.4%) and right (+6.7%). Wearing the splint reduced the area of sway deflections by about 31.5% in the bipedal stance and by about 2.4% (left) and 28.2% (right) in the unipedal stance. The CoP trace was reduced in the sagittal plane by approximately 8.2% in the right single-leg stance.

CONCLUSIONS

The major findings seem to demonstrate that wearing a splint that keeps the jaw close to the centric relation may increase the cervical ROM and may improve balance stability in male recreational athletes. Changing the jaw relation in athletes can possibly aid the release of performance potentials by improving coordination skills.

Deep Cervical Muscles and Functionality in Patients with Chronic Tension-Type Headache: An Observational Study

Background and objectives: Chronic tension-type headache (TTH) is the type of headache with the highest prevalence. The involvement of musculoskeletal structures in TTH is supported by evidence in the scientific literature. Among these, deep cervical muscle strength appears to be related to the function of the cervical spine and the clinical characteristics of TTH. This study aimed to correlate anatomical, functional, and psychological variables in patients with TTH. Materials and methods: An observational descriptive study was carried out with 22 participants diagnosed with TTH for at least six months. The characteristics of headaches, including ultrasound-based deep neck flexor and extensor muscle thickness, range of motion (ROM), and pressure pain threshold (PPT), were recorded. We also conducted the Pain Vigilance and Awareness Questionnaire (PVAQ) and the Craniocervical Flexion Test (CCFT). Results: Moderate-large negative correlations were found between the PVAQ and the muscle thickness of right deep flexors contracted (r = -0.52; p = 0.01), left multifidus contracted (r = -0.44; p = 0.04), right multifidus at rest (r = -0.48; p = 0.02), and right multifidus contracted (r = -0.45; p = 0.04). Moderate-large positive correlations were found between the CCFT score and the left cervical rotation ROM (r = 0.53; p = 0.01), right cervical rotation ROM (r = 0.48; p = 0.03), muscle thickness of left multifidus contracted (r = 0.50; p = 0.02), and muscle thickness of right multifidus at rest (r = 0.51; p = 0.02). The muscle thickness of the contracted right deep cervical flexors showed a moderate negative correlation with headache intensity (r = -0.464; p = 0.03). No correlations were found between PPT and the rest of the variables analyzed. Conclusions: In patients with TTH, a higher thickness of deep cervical muscles was associated with higher ROM and higher scores in the CCFT. In turn, the thickness of deep cervical muscles showed negative correlations with pain hypervigilance and headache intensity. These results contribute to a better understanding of the physical and psychosocial factors contributing to the development of TTH, which is useful for implementing appropriate prevention and treatment measures.

Alterations in kinematics of temporomandibular joint associated with chronic neck pain

BACKGROUND

Temporomandibular disorder (TMD) is an umbrella term for pain and dysfunction of the temporomandibular joint (TMJ) and its associated structures. Patients with TMD show changes in TMJ kinematics and masticatory muscle activation. TMD is commonly comorbid with non-specific chronic neck pain (NCNP), which may be one of the risk factors for TMD.

OBJECTIVES

This study aimed to investigate whether patients with NCNP have altered TMJ kinematics and masticatory muscle activity.

METHODS

This was a cross-sectional exploratory study including 19 healthy participants and 20 patients with NCNP but without TMD symptoms. TMJ kinematics was measured during mouth opening and closing, jaw protrusion and jaw lateral deviation. Surface electromyography was used to record the muscle activity of the anterior temporalis, masseter, sternocleidomastoid and upper trapezius while clenching. Furthermore, cervical posture, cervical range of motion (ROM) and pressure-pain threshold of the neck and masticatory muscles were measured.

RESULTS

Compared with the healthy group, the NCNP group showed significantly reduced upper cervical rotation ROM (p = .041) and increased condylar path length (p = .02), condylar translation (opening p = .034, closing p = .011) and mechanical pain sensitivity of the upper trapezius (p = .018). Increased condylar translation was significantly correlated with reduced upper cervical mobility and poor cervical posture (r = -0.322 to -0.397; p = .012-.046).

CONCLUSION

Increased condylar translation and path length in patients with NCNP may indicate poor control of TMJ articular movement, which may result from neck pain or may be a compensation for limited neck mobility. Evaluation of excessive TMJ translation may be considered in patients with NCNP.

Association of cervical spine signs and symptoms with temporomandibular disorders in adults: a systematic review protocol

OBJECTIVE

The objective of this systematic review is to assess the evidence of association of cervical spine signs and symptoms with temporomandibular disorders (TMD). This will help to lend credence to mechanisms supporting the association in order to improve care strategies for this condition.

INTRODUCTION

The association of cervical spine impairments (in relation to neck posture, cervical spine mobility, muscle tenderness, muscle activity, and neck disability) with TMD has been widely discussed in the literature. Clarification of this relationship is important for health professionals to better assess and treat TMD.

INCLUSION CRITERIA

Eligible studies will include participants aged 18 years and over, with a diagnosis of TMD from the Research and Diagnostic Criteria for Temporomandibular Disorders or a revised version. Exclusion criteria will be participants with previous temporomandibular joint surgery, history of trauma or fracture in the temporomandibular joint or the craniomandibular system; serious comorbid conditions such as cancer, rheumatic disease, and neurological problems; primary cervical spine disorders such as disc herniation or spinal degenerative changes; or systemic disease such as ankylosing spondylitis.

METHODS

The search for articles will be conducted in the databases PubMed, PEDro, CINAHL, Web of Science, and Embase, without language or time restrictions. Two independent reviewers will review the title, abstract, and full texts of identified studies; select studies against the inclusion criteria; assess the methodological quality of eligible studies using critical appraisal tools; and perform data extraction. Relevant quantitative data will be pooled with statistical meta-analysis, when possible.

SYSTEMATIC REVIEW REGISTRATION NUMBER

PROSPERO CRD42019123698.

Efficacy of different combinations of physiotherapy techniques compared to exercise and patient education in temporomandibular disorders: A randomized controlled study

OBJECTIVE

This study aims to investigate the efficacy of different types of physiotherapy approaches in individuals with cervical myofascial painful temporomandibular disorders (TMDs).

METHODS

Seventy-five participants with myofascial pain of jaw muscles and cervical myofascial pain were randomized into three groups: exercise group (E), low-level laser therapy group (LLLT), and manual pressure release group (MPR). All patients were assessed before treatment and after 12 sessions of treatment.

RESULTS

Significant improvement was seen in all groups' pressure pain threshold (PPT) values (p < 0.01). Some masticatory and neck muscles' PPT changes in MRP and LLLT groups were significantly higher than the exercise group (p < 0.05).

CONCLUSION

Exercise therapy is an effective approach for treatment of TMDs. Additionally, LLLT combined with exercise and MPR combined with exercise have better effects than only exercise therapy. Multimodal treatment approaches should include exercise to achieve better results in clinical practice.

The association between specific temporomandibular disorders and cervicogenic headache

BACKGROUND AND AIMS

Upper neck signs, symptoms and hypomobility have been shown to present with a higher prevalence in patients with temporomandibular disorders (TMDs). However, there is currently no evidence of an association between specific TMDs and cervicogenic headache (CGH). Therefore, the aim of this study was to evaluate the odds ratio and the relative risk of CGH in patients with specific TMDs.

METHOD

116 participants, including 74 patients with TMD (pain-related/intraarticular/mixed TMD) and 42 healthy controls took part in this study. The TMD diagnosis was made by senior faculty members of the Dental School according to the Diagnostic Criteria for TMD, while the cervical diagnosis was made by a qualified senior physical therapist. The analysis comprised the evaluation of the odds ratio of CGH among patients with TMD and the relative risk (RR) for CGH during 14-24 months of follow-up.

RESULTS

Significantly higher odds ratios of cervicogenic headache were found among pain-related and mixed TMD (12.17 and 10.76, respectively) versus healthy controls. During the 14-24 months of follow-up, there was no significant difference of relative risk for CGH among patients with TMD versus healthy controls.

SUMMARY AND CONCLUSIONS

The results support a clear clinical association between painful TMD (pain-related and mixed TMD) and cervicogenic headache.

Orthodontic Treatment and Craniocervical Posture in Patients with Temporomandibular Disorders: An Observational Study

Orthodontic treatment acts through the application of forces and/or by stimulating and redirecting the functional forces within the craniofacial complex. Considering the interrelationship between craniomandibular and craniocervical systems, this intervention may alter craniocervical posture. Thus, our aim is to (a) compare craniocervical posture, hyoid bone position, and craniofacial morphology before, after, and also in the contention phase at least one year after the orthodontic treatment, in patients with temporomandibular disorders and (b) to verify whether the presence of condylar displacement, the skeletal class, or the facial biotype interferes with the abovementioned outcomes. To do so an observational, analytical, longitudinal, and retrospective design study was carried out. A non-probabilistic convenience sampling method was applied. The sample consisted of clinical records of patients diagnosed with temporomandibular disorders in order to compare pre-orthodontic treatment with post-orthodontic treatment (n = 42) and contention phase data (n = 26). A cephalometric analysis of several variables was performed. The p-value was set as 0.05. When the pre- and post-orthodontic treatment data were analyzed, there were statistically significant changes in variables concerning craniocervical posture (CV angle, C0-C1, and AA-PNS) and also concerning hyoid bone position (C3-Rgn). When pre- and post-orthodontic treatment and contention phase data were analyzed the variables concerning craniocervical posture (C0-C1, CVT/Ver, NSL/OPT, NSL/CVT, NSL/Ver; OPT/CVT, OPT/Ver) and facial biotype had statistically significant changes. This allowed us to conclude that in the sample studied, there were significant differences regarding hyoid bone position (pre- versus post-orthodontic treatment) and craniocervical posture (pre- versus post-orthodontic versus contention), with the craniocervical posture being prone to return to basal values. The presence of condylar displacement was found to significantly increase the H-H1 distance in the three moments of evaluation. Facial biotype was found to significantly increase the NSL/Ver angle on hypodivergent compared to hyperdivergent in the contention phase.

Cervical musculoskeletal disorders in patients with temporomandibular dysfunction: A systematic review and meta-analysis

OBJECTIVE

To verify which are the neck musculoskeletal disorders presented by individuals with temporomandibular disorders (TMD).

METHODS

It is a systematic review and meta-analysis that were included cohort, case-control and cross-section studies that analyzed the presence of cervical musculoskeletal disorders in individuals with TMD, with age between 18 and 55 years. The searches were carried out in the databases: Medline/PubMed, Cinahl, Web of Science, Cochrane, Lilacs and Scopus; and there was no linguistic or temporal restriction. The evidence quality was evaluated by GRADE system and methodological quality by Newcastle-Ottawa Quality Assessment Scale (NOS) and the risk of publication bias assessed by the funnel plot graph. The data was quantitatively analyzed by the meta-analysis using the mean differences (MD) as an effect measure.

RESULTS

There were included 21 manuscripts in the synthesis, of theses 16 were evaluated by meta-analysis with methodological quality ranging from poor to excellent by NOS scale. Individuals with TMD present lower endurance of extensor neck muscle compared to TMD-free (MD = -194.66s [95%CI: 212.44;-176.88]), with moderate to excellent quality. As, upper neck hymobility on the right (MD = -8.59° (95%CI: -10.43°;-6.75°) and left (MD = -7.99° (95%CI: -9.63°;-6.35°), and in all global neck movements. Also, individuals with TMD presented worse self-reported neck disability (MD = 7.91 (95%CI: 7.39; 8.43)) compared to free-TMD.

CONCLUSION

There is moderate and strong evidence that patients with TMD present lower endurance of extensor neck muscle, global and upper neck hypomobility, worse self-reported neck disability, however, their cranio-cervical posture is similar to individuals without TMD, based on a moderate to excellent methodological quality.

SYSTEMATIC REVIEW REGISTRATION NUMBER

PROSPERO CRD42018103918.

Craniocervical and Cervical Spine Features of Patients with Temporomandibular Disorders: A Systematic Review and Meta-Analysis of Observational Studies

To assess neck disability with respect to jaw disability, craniocervical position, cervical alignment, and sensorimotor impairments in patients with temporomandibular disorders (TMD), a systematic review and meta-analysis of observational studies trials were conducted. The meta-analysis showed statistically significant differences in the association between neck disability and jaw disability (standardized mean difference (SMD), 0.72 (0.56-0.82)). However, results showed no significant differences for cervical alignment (SMD, 0.02 (-0.31-0.36)) or for the craniocervical position (SMD, -0.09 (-0.27-0.09)). There was moderate evidence for lower pressure pain thresholds (PPT) and for limited cervical range of motion (ROM). There was limited evidence for equal values for maximal strength between the patients with TMD and controls. There was also limited evidence for reduced cervical endurance and conflicting evidence for abnormal electromyographic (EMG) activity and motor control in TMD patients. Results showed a clinically relevant association between cervical and mandibular disability in patients with TMD. Regarding sensory-motor alterations, the most conclusive findings were observed in the reduction of PPT and cervical ROM, with moderate evidence of their presence in the patients with TMD. Lastly, the evidence on impaired motor control and cervical EMG activity in patients with TMD was conflicting.

Bridging the gap between temporomandibular disorders, static balance impairment and cervicogenic dizziness: Posturographic and clinical outcomes

Several studies have investigated the possible influence of temporomandibular disorders (TMD) on body posture and whether cervical spine disorders, such as cervicogenic dizziness (CGD) could play an additional role in affecting static balance. The purpose of this study was to analyze static postural behavior by means of static posturography, in patients affected by either TMD or CGD alone or by both conditions, and to compare findings with a group of healthy subjects. Significant changes in posturographic parameters were found among the three groups of patients and when compared with controls. When the three study groups were compared to each other, subjects affected by a combination of TMD and CGD showed worse postural performances with respect to subjects affected by CGD or TMD alone. Correlations with self-perceived dizziness, anxiety, depression and jaw functionality, investigated by means of validated questionnaires, were found among all patient groups. These results provide new evidences for the presence of static balance alterations in patients suffering from TMD with and without associated cervical spine impairment, by using a reliable diagnostic technique. Further studies are needed in order to identify any causal relation between these two disorders.

Effectiveness of physical therapy in addition to occlusal splint in myogenic temporomandibular disorders: protocol of a randomised controlled trial

INTRODUCTION

Temporomandibular disorders (TMDs) are considered a collection of musculoskeletal conditions involving the masticatory muscles, the temporomandibular joint and associated structures. The myogenous group appears to represent the most frequently diagnosed category. In the context of a multimodal approach, splint therapy and musculoskeletal physiotherapy are often considered as a preferred therapy. The purpose of this study will be to investigate the effects of musculoskeletal physiotherapy combined with occlusal splint and education versus occlusal splint and education alone in the treatment of chronic myogenous TMD on pain and mandibular range of motion.

METHODS AND ANALYSIS

All consecutive adults complaining of TMDs presented to the Department of Biomedical and Neuromotor Sciences of the University of Bologna will be considered eligible. Inclusion criteria shall be based on the presence of myogenous TMDs, as diagnosed through clinical examination in reference to the international diagnostic criteria of TMDs. Randomisation, concealed allocation, blinded assessment and intention-to-treat analysis will be employed. The splint therapy will consist of the use of the splint every night and concurrent delivery of an educational programme; the protocol shall have a duration of three consecutive months. The combined musculoskeletal physiotherapy, splint therapy and education will additionally consist of manual therapy techniques and exercise; such protocol shall consist of a duration of three consecutive months, inclusive of 10 sessions for the enhanced elements. All outcome measures will be collected at baseline, after treatment and at a 6 months follow-up.

ETHICS AND DISSEMINATION

Ethical approval has been obtained from the Independent Ethic Committee in Clinical Research of AUSL Bologna-Italy (47/2018/SPER/AUSLBO). Pursuant to applicable rules,we will obtain informed consent from each participant and collect data anonymously to maintain privacy. Results will be disseminated to clinicians and researchers through peer-reviewed publications and conferences.

TRIAL REGISTRATION NUMBER

NCT03726060.

Relationship between specific temporomandibular disorders and impaired upper neck performance

Upper neck impairments are more prevalent in patients with temporomandibular disorders (TMDs) but the differences between specific types of TMDs are unclear. This study evaluated the distribution of such impairments among different forms of TMD. In total, 116 participants (86 women and 30 men, age range 21-75 yr) were investigated. Forty-two individuals had no TMDs and were assigned to the control group. The remaining 74 patients were assigned to one of three groups based on the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) findings: pain-related (n = 37); intra-articular (n = 17); or mixed (combined pain-related and intra-articular) (n = 20). Analyses of impairments included between-group comparisons of key parameters of upper neck performance (active/passive mobility and muscular capabilities) and pain (subjective neck disability and pain sensitivity). Patients in the pain-related and mixed TMD groups were found to have decreased upper neck mobility in the cervical flexion-rotation test compared with patients in intra-articular and control groups, as well as poorer capabilities of the deep neck flexor muscles in the cranio-cervical flexion test compared to the control group. It was concluded that patients with pain-related TMD diagnoses are more likely to experience significant upper-neck hypomobility and poor muscular capabilities than patients with intra-articular diagnoses of TMD.

Temporomandibular disorders and cervicogenic dizziness: Relations between cervical range of motion and clinical parameters

OBJECTIVE

To analyze the cervical range of motion (CROM) and clinical parameters in patients affected by myogenous temporomandibular disorders (TMD), cervicogenic dizziness (CGD), both TMD and CGD (TMD/CGD), and a group of healthy subjects (HS).

METHODS

CROM degrees, Dizziness Handicap Inventory (DHI), Tampa Scale for Kinesiophobia (TSK-17), Hospital Anxiety and Depression Scale (HADS), and Jaw Functional Limitation Scale 20 (JFLS-20) scores were compared between 46 TMD patients, 49 CGD subjects, 43 TMD/CGD patients, and 98 HS.

RESULTS

TMD/CGD and CGD patients demonstrated significantly lower CROM degrees and higher DHI, TSK-17, and HADS values when compared to TMD patients. TMD/CGD and TMD patients demonstrated higher JFLS-20 values when compared to CGD and HS. Significant negative correlations were found in TMD/CGD and TMD patients between JFLS-20 and CROM in flexion and extension.

DISCUSSION

Present findings demonstrated a relation between spine movement impairment and TMD.

International consensus on the most useful assessments used by physical therapists to evaluate patients with temporomandibular disorders: A Delphi study

OBJECTIVE

To identify assessment tools used to evaluate patients with temporomandibular disorders (TMD) considered to be clinically most useful by a panel of international experts in TMD physical therapy (PT).

METHODS

A Delphi survey method administered to a panel of international experts in TMD PT was conducted over three rounds from October 2017 to June 2018. The initial contact was made by email. Participation was voluntary. An e-survey, according to the Checklist for Reporting Results of Internet E-Surveys (CHERRIES), was posted using SurveyMonkey for each round. Percentages of responses were analysed for each question from each round of the Delphi survey administrations.

RESULTS

Twenty-three experts (completion rate: 23/25) completed all three rounds of the survey for three clinical test categories: 1) questionnaires, 2) pain screening tools and 3) physical examination tests. The following was the consensus-based decision regarding the identification of the clinically most useful assessments. (1) Four of 9 questionnaires were identified: Jaw Functional Limitation (JFL-8), Mandibular Function Impairment Questionnaire (MFIQ), Tampa Scale for Kinesiophobia for Temporomandibular disorders (TSK/TMD) and the neck disability index (NDI). (2) Three of 8 identified pain screening tests: visual analog scale (VAS), numeric pain rating scale (NRS) and pain during mandibular movements. (3) Eight of 18 identified physical examination tests: physiological temporomandibular joint (TMJ) movements, trigger point (TrP) palpation of the masticatory muscles, TrP palpation away from the masticatory system, accessory movements, articular palpation, noise detection during movement, manual screening of the cervical spine and the Neck Flexor Muscle Endurance Test.

CONCLUSION

After three rounds in this Delphi survey, the results of the most used assessment tools by TMD PT experts were established. They proved to be founded on test construct, test psychometric properties (reliability/validity) and expert preference for test clusters. A concordance with the screening tools of the diagnostic criteria of TMD consortium was noted. Findings may be used to guide policymaking purposes and future diagnostic research.

Intra-rater and inter-rater reliability of cervical active range of movement in young asymptomatic adults using inertial sensors

Objectives: Current literature is scarce about the use of an inertial sensor to measure cervical active range of motion (aROM). The objective of the present study is to determine inter- and intra-reliability in the measurement of cervical aROM using inertial sensors in asymptomatic individuals.Materials and methods: Twenty asymptomatic individuals participated in the study. Two different physiotherapists measured each participant for cervical aROM (6 movements). The sequence of movements and the explanations given were standardized. The rater's order of measurement was randomized.Results: For the intra-rater results, the intraclass correlation coefficient (ICC) values for all cervical movements were good for Rater A (ICC >0.90) and Rater B (ICC >0.90). For the inter-rater results, the ICC values were above 0.75 for all movements, indicating a good level of reliability. Also, values obtained in SEM, MDC₉₀ and LOA indicate good agreement.Conclusion: The data obtained in this study suggest that inertial sensors can be used in clinics due to their high intra- and inter-rater ICC (>0.80). Also, its low economic cost, easy handling, and various utilities make this tool a useful alternative in the measurement of cervical aROM.

Upper cervical spine abnormalities as a radiographic index in the diagnosis and treatment of temporomandibular disorders

OBJECTIVE

The aim of this study was to investigate the clinical characteristics and treatment outcomes of patients with temporomandibular disorders (TMD) according to the presence of upper cervical spine abnormalities and craniofacial morphology.

STUDY DESIGN

Clinical examinations were conducted on 43 patients with TMD. Upper cervical spine characteristics (fusion, posterior arch deficiency [PAD], and craniofacial morphology) reflecting head-and-neck posture were evaluated on lateral cephalograms. Condylar bone changes in the temporomandibular joint were evaluated by using cone beam computed tomography. Clinical characteristics and treatment outcomes after 1 year of conservative therapy were statistically analyzed between groups, according to the presence of upper cervical spine abnormalities.

RESULTS

Pain on neck muscle palpation was more frequent in patients with cervical fusion (P = .019) and with either fusion or PAD (P = .004) before treatment. Patients with PAD had smaller comfortable mouth opening ranges compared with those without the deficiency (P = .044) before treatment and smaller comfortable (P = .020) and maximum (P = .021) mouth opening ranges after treatment. Patients with PAD also had mouth opening limitation (P = .028) and pain on masticatory muscle palpation (P = .014) more frequently after treatment compared with patients without the deficiency.

CONCLUSIONS

Associations exist between upper cervical spine characteristics and treatment outcomes in patients with TMD, suggesting such parameters as a possible radiographic index in TMD diagnosis and treatment.

Preclinical Signs of a Temporomandibular Disorder in Female Patients With Episodic Cervicogenic Headache Versus Asymptomatic Controls: A Cross-Sectional Study

BACKGROUND

The International Classification of Headache Disorders, 3rd Edition, accepted "headache attributed to temporomandibular disorders" as a valid headache. The neurophysiologic interplay between cervical structures and the temporomandibular joint, however, might also suggest that a temporomandibular disorder could develop in patients with cervicogenic headache.

OBJECTIVE

To compare the presence of preclinical temporomandibular signs between female patients with episodic cervicogenic headache and a control group.

DESIGN

Case-controlled cross-sectional design.

SETTING

Institutional setting: Hasselt University.

PARTICIPANTS

Twenty-two women (mean age ± SD: 20.7 ± 2.5 years) with episodic cervicogenic headache, without temporomandibular signs and 22 matched (gender, age, level of education, occupation) asymptomatic controls (21 ± 2.3 years).

METHODS

(Un)assisted temporomandibular range of motion, pressure pain thresholds, painful palpations were examined and the level of perceived stress was measured.

MAIN OUTCOME MEASUREMENTS

Temporomandibular range of motion (mm), pressure pain thresholds (kPa/cm²), painful palpations (yes/no), and level of perceived stress (Perceived Stress Scale).

RESULTS

Maximal mouth-opening was significantly smaller in the headache group (P <.05; effect size [ES] -0.45). Palpation of the masseter resulted in significantly more positive pain responses in the headache group at the left (P = .009; ES ∞) and right (P = .002;ES 17.5) origin, left (P = .004; ES 14.54) and right (P = .03; ES 5.71) body and left (P < .001; ES 12) insertion. Significantly lower pressure pain thresholds on the left and right anterior (P = .03; ES -0.33 resp. P = .02; ES -0.35), central (P = .003; ES 1.02 resp. P = .02; ES 0.79) and right posterior (P = .03; ES 0.62) temporalis and right tibialis anterior (P = .03; ES -0.33) were measured in the headache group. The level of perceived stress was significantly higher (P = .02) in the headache group.

CONCLUSIONS

Patients with episodic cervicogenic headache present with signs of a preclinical temporomandibular disorder and sensitization. The smaller range of motion, lower pressure pain thresholds, and higher levels of stress accentuate the multidimensionality of the problem.

LEVEL OF EVIDENCE

IV.

Impact of orthognathic surgery on the body posture

BACKGROUND

Postural control is classically described as being based on the visual, vestibular, and proprioceptive musculo-articular sensory systems. The influence of mandibular proprioception on postural stabilization remains controversial. Most previous studies analyzed how postural stability is influenced by partial changes in mandibular proprioception (dental occlusion and jaw position).

RESEARCH QUESTION

In the present experiment, we asked whether drastic mandibular changes, resulting from orthognathic surgery (including dental, joint and muscular efferents), modify postural control.

METHODS

The analyzes were performed in 22 patients tested before, and 2.5 months, after orthognathic surgery for treatment of dysmorphic jaws. Experiments were performed under 4 experimental conditions: 2 visual conditions: Eyes Open (EO) and Eyes Closed (EC), and 2 occlusal conditions: Occlusion (OC: mandible positioned by the contact of the teeth), and Rest Position (RP: mandible positioned by the muscles without tooth contact). The analyses focused on head orientation in the frontal plane and on postural stabilization in a static task, consisting of standing upright.

RESULTS

The results show that, 2.5 months after orthognathic surgery, head orientation in the frontal plane was improved, since patient's external intercanthal lines became closer to the true horizontal line when they were tested EC and in OC condition. Postural responses, based on the wavelet transformation data, highlight an improvement in maintaining an upright stance for all the tested sensory conditions. However, such improvement was greater in the EC and RP conditions.

SIGNIFICANCE

These results show, for the first time, that after drastic mandibular changes, the weight of proprioceptive cues linked to the mandibular system may be so enhanced that it may constitute a new reference frame to orient the head in space, in darkness, and improve static postural stabilization, even in the presence of visual cues.

The C0-C2 axial rotation test: normal values, intra- and inter-rater reliability and correlation with the flexion rotation test in normal subjects

OBJECTIVES

Impairment in upper cervical spine mobility is associated with cervicogenic headache severity and disability. Measures of such mobility include the flexion-rotation test (FRT), which requires full cervical flexion and may be influenced by lower cervical spine dysfunction. The C0-C2 axial rotation test also evaluates upper cervical mobility but normal values and reliability have not been reported. Our objective is to determine normal values, and intra-rater and inter-rater reliability of the C0-C2 axial rotation test.

METHODS

Two therapists independently evaluated the FRT and C0-C2 axial rotation test with an iPhone compass application on 32 asymptomatic subjects with mean age 40.53 (SD 11.64) years on two occasions. Measurement procedures were standardized; and order of testing randomized.

RESULTS

For the FRT and C0-C2 axial rotation test reliability was high (ICC > 0.88). For rater one, Mean range to the left during the FRT and C0-C2 axial rotation test was 45.0° (6.04) and 14.43° (2.94), respectively, while range to the right was 44.6° (6.57) and 15.44° (2.68). For the FRT and C0-C2 axial rotation test the standard error of measurement was at most 2°, while the minimum detectable change was at most 4°. A strong positive correlation exists between the FRT and C0-C2 axial rotation test (r = 0.84, P < 0.01).

DISCUSSION

The range recorded during the C0-C2 axial rotation test and FRT have high levels of reliability when evaluated using an iPhone. The strong correlation between the FRT and C0-C2 axial rotation test indicate that both may be measuring similar constructs, but each test needs to be referenced to normal values.

Postural stability in subjects with temporomandibular disorders and healthy controls: A comparative assessment

PURPOSE OF THE STUDY

The influence of the stomatognathic apparatus on body posture is a continuously discussed topic with contrasting results. The aim of this study is to analyze differences in postural stability between subjects with and without myogenous TMD.

METHODS

25 subjects affected by myogenous TMD according with DC/TMD (6 males, 19 females; mean age 31.75±6.68years) and a healthy control group of 19 subjects (4 Males, 15 Females; mean age 27.26±3.85years) were enrolled in the study. Both groups underwent a posturo-stabilometric force platform exam under different mandibular and visual conditions. Sway area and sway velocity of the COP (Center Of foot Pressure) posturo-stabilometric parameters were evaluated and compared applying Mann-U-Whitney statistical test.

RESULTS

The sway area and sway velocity parameters resulted statistically significantly higher in the TMD group (sway area p<0.01; sway velocity p<0.05) in mandibular maximum intercuspation and rest positions with eyes open.

CONCLUSIONS

This study demonstrates a significant difference in body postural stability between subjects with myogenous TMD and healthy controls. In particular, sway area and sway velocity postural parameters are increased in these subjects.

Cervical flexion-rotation test and physiological range of motion - A comparative study of patients with myogenic temporomandibular disorder versus healthy subjects

BACKGROUND

Temporomandibular Disorders (TMD) refer to several common clinical disorders which involve the masticatory muscles, the temporomandibular joint (TMJ) and the adjacent structures. Although neck signs and symptoms are found with higher prevalence in TMD patients compared to the overall population, whether limitation of cervical mobility is an additional positive finding in this cohort is still an open question.

OBJECTIVE

To compare the physiological cervical range of motion (CROM) and the extent of rotation during cervical flexion (flexion-rotation test, FRT) in people with TMD (muscular origin) and healthy control subjects.

METHOD

The range of motion of the neck and FRT was measured in 20 women with myogenic TMD and 20 age matched healthy controls.

RESULTS

Women with myogenic TMD had significantly lower FRT scores compared to their matched healthy women. No difference was found between groups in CROM in any of the planes of movement. The FRT was positive (less than 32°) in 90% of the TMD participants versus 5% in the healthy control but the findings were not correlated with TMD severity.

CONCLUSION

The results point out a potential involvement of the upper cervical joints (c1-c2) in women with myogenic TMD.

Does altered mandibular position and dental occlusion influence upper cervical movement: A cross-sectional study in asymptomatic people

OBJECTIVE

Gross mandibular position and masticatory muscle activity have been shown to influence cervical muscles electromyographic activity. The purpose of this study was to investigate the influence of three different mandible positions including conscious occlusion, tongue tip against the anterior hard palate (Palate tongue position) and natural resting position (Rest), on sagittal plane cervical spine range of motion (ROM) as well as the flexion-rotation test (FRT) in asymptomatic subjects.

MATERIALS AND METHODS

An experienced single blinded examiner evaluated ROM using an Iphone in 22 subjects (7 females; mean age of 29.91years, SD 5.44).

RESULTS

Intra-rater reliability for range recorded was good for the FRT with ICC (intraclass correlation) 0.95 (95% CI: 0.88-0.98) and good for sagittal plane cervical ROM with ICC 0.90 (95% CI: 0.77-0.96). A repeated measures ANOVA determined that mean ROM recorded during the FRT differed significantly between assessment points (F(1.99, 41.83) = 19.88, P < 0.001). Bonferroni Post hoc tests revealed that both conscious Occlusion and Palate tongue position elicited a significant large reduction in ROM recorded during the FRT from baseline (p < 0.01). Despite this, one activation strategy did not influence ROM more than the other. An additional repeated measures ANOVA determined that mean sagittal cervical ROM did not significantly vary between assessment points (F(2, 42) = 8.18, P = 0.08).

CONCLUSION

This current study provided further evidence for the influence of the temporomandibular region on upper cervical ROM. Results suggest that clinicians should focus on the natural mandible rest position when evaluating upper cervical mobility.

Changes in cervical movement impairment and pain following orofacial treatment in patients with chronic arthralgic temporomandibular disorder with pain: A prospective case series

The purpose of this study was to investigate the influence of isolated temporomandibular joint (TMJ) manual therapy on pain and range of motion (ROM) of the TMJ and cervical spine including flexion-rotation test (FRT) in people suffering chronic pain arising from chronic arthralgic temporomandibular disorder (TMD). An experienced clinician managed a case series of 12 patients with TMD (mean duration 28.6 months +/- 26.9). The intervention comprised four-weekly sessions of transverse medial accessory TMJ mobilization and advice. Patients were examined prior to and one-week following the intervention period. Outcome measures included jaw disability (JFLS-20), jaw pain measured by Visual Analogue Scale (VAS), maximal mouth opening ROM, cervical ROM including FRT, and pain during cervical movement. A paired t-test revealed significant improvement following the intervention in disability (p < 0.001), VAS pain score at rest (p < 0.001) and at maximum mouth opening (p < 0.001), jaw opening ROM (p < 0.001), FRT ROM to the left (p = 0.024) and right (p = 0.001). In contrast, no significant change was identified for total cervical ROM (p = 0.905). After the intervention, five patients (41.66%) had no pain at rest or at maximal mouth opening, and all had a negative FRT. The effect sizes indicate a moderate to strong, clinically significant effect for all variables apart from total cervical ROM. While a case series cannot identify a cause and effect relationship, these results provide preliminary evidence for the influence of TMJ manual therapy on measures of TMD including pain, as well as upper but not whole cervical movement and associated pain in patients with a diagnosis of TMJ arthralgia.

Influence of the mandibular position on the active cervical range of motion of healthy subjects analyzed using an accelerometer

OBJECTIVE

The aim of this study is to analyze the influence of the mandibular positions (habitual rest position, habitual maximum intercuspation, habitual maximum intercuspation with clenching, and mandibular position with cotton rolls) on the active cervical range of motion (ROM) (flexion-extension, lateroflexions, rotations) using an accelerometer in a sample of healthy subjects.

METHODS

A total of 21 (14 M, 7 F) healthy volunteers aged from 18 to 27 years (mean age 23.88 ± 2.34 years; mean weight 67.86 ± 11.38 kg; mean height 172.52 ± 9.00 cm) underwent a cervical range of movement examination using a 9-axis accelerometer. A one-way ANOVA analysis was performed in order to statistically evaluate the effective influence of the mandibular position on the recorded parameters.

RESULTS

The analysis showed no statistically significant differences (all p-values > 0.1) with variations smaller than three degrees among the different mandibular positions.

DISCUSSION

The mandibular position seems to have no influence on the active cervical ROM in healthy subjects. Further studies are needed to assess the usefulness of the accelerometer in the cervical analysis of temporomandibular disorder subjects.

Do subjects with acute/subacute temporomandibular disorder have associated cervical impairments: A cross-sectional study

BACKGROUND

There is preliminary evidence of cervical musculoskeletal impairment in some temporomandibular disorder (TMD) pain states.

OBJECTIVES

To determine whether people with TMD, classified as either mild or moderate/severe TMD, have more cervical signs of dysfunction than healthy subjects.

DESIGN

Cross-sectional survey.

METHOD

Based on the Conti Amnestic Questionnaire and examination of the temporomandibular joint (Axis I classification of the Research Diagnostic Criteria for TMD), of 144 people examined 59 were classified to a mild TMD group, 40 to a moderate/severe TMD group and 45 to an asymptomatic control group without TMD. Subjects were evaluated for signs of cervical musculoskeletal impairment and disability including the Neck Disability Index, active cervical range of motion, the Flexion-Rotation Test, mechanical pain threshold of the upper trapezius and obliquus capitis inferior muscles, Cranio-Cervical Flexion test and passive accessory movements of the upper 3 cervical vertebrae.

RESULTS

According to cervical musculoskeletal dysfunction, the control group without TMD were consistently the least impaired and the group with moderate/severe TMD were the most impaired. These results suggest, that the more dysfunction and pain is identified in the temporomandibular region, the greater levels of dysfunction is observable on a number of cervical musculoskeletal function tests. The pattern of cervical musculoskeletal dysfunction is distinct to other cervical referred pain phenomenon such as cervicogenic headache.

CONCLUSION

These findings provide evidence that TMD in an acute/subacute pain state is strongly related with certain cervical spine musculoskeletal impairments which suggests the cervical spine should be examined in patients with TMD as a potential contributing factor.

Chronic Neck Pain and Cervico-Craniofacial Pain Patients Express Similar Levels of Neck Pain-Related Disability, Pain Catastrophizing, and Cervical Range of Motion

Background. Neck pain (NP) is strongly associated with cervico-craniofacial pain (CCFP). The primary aim of the present study was to compare the neck pain-related disability, pain catastrophizing, and cervical and mandibular ROM between patients with chronic mechanical NP and patients with CCFP, as well as asymptomatic subjects. Methods. A total of 64 participants formed three groups. All participants underwent a clinical examination evaluating the cervical range of motion and maximum mouth opening, neck disability index (NDI), and psychological factor of Pain Catastrophizing Scale (PCS). Results. There were no statistically significant differences between patients with NP and CCFP for NDI and PCS (P > 0.05). One- way ANOVA revealed significant differences for all ROM measurements. The post hoc analysis showed no statistically significant differences in cervical extension and rotation between the two patient groups (P > 0.05). The Pearson correlation analysis shows a moderate positive association between NDI and the PCS for the group of patients with NP and CCFP. Conclusion. The CCFP and NP patient groups have similar neck disability levels and limitation in cervical ROM in extension and rotation. Both groups had positively correlated the NDI with the PCS.