Decreased neck muscle strength is highly associated with pain in cervical dystonia patients treated with botulinum toxin injections

Effects of an integrated neuromuscular inhibition technique program on neck muscle strength and endurance in individuals with chronic mechanical neck pain

BACKGROUND

The aim of this study was to investigate whether the application of the integrated neuromuscular inhibition technique (INIT) combined with therapeutic exercise (TE) can provide faster and greater improvement in maximum isometric strength and isometric endurance of the neck muscles in patients with chronic mechanical neck pain (CMNP).

METHODS

In this 10-week, single-blind clinical trial, 40 participants (men and women) with CMNP were divided into two groups. The intervention group (IG) followed a TE program in combination with the INIT, while the control group (CG) followed the same TE program without the INIT technique. Changes in maximum isometric strength and isometric endurance of the neck muscles were evaluated before, during, and after the intervention, with follow-up measurements taken at 1, 3, and 6 months after the intervention. Analysis of variance with repeated measures was applied.

RESULTS

Both groups showed a significant improvement in all dependent measures after the intervention (p < .05). These changes were maintained for both groups 6 months after the intervention. However, the IG showed a greater improvement in the maximum isometric strength of neck flexion and an improved craniocervical flexion test score compared with the CG.

CONCLUSION

The combination of TE and INIT had a positive effect on neck muscle strength and endurance in individuals suffering from CMNP as compared with TE alone.

Long-term quality of life in cervical dystonia after treatment with abobotulinum toxin A: a 2-year prospective study

BACKGROUND

The short-term quality of life (QoL) in cervical dystonia (CD) after treating with abobotulinum toxin A (Abo-BTX A) and neubotulinum toxin A (Neu-BTX A) have been studied in Thai CD patients. However; the long-term study has not been published.

OBJECTIVE

The aim of the present study was to determine long-term improvement of the health-related quality of life (HRQoL) after eight injections of Abo-BTX A over 2 years in CD patients.

PATIENTS AND METHODS

A 2-year prospective study on the QoL of CD patients, as measured by HRQoL, before and after receiving eight injections of Abo-BTX A at 3-month intervals over a 2-year treatment period was performed. The disease-specific HRQoL was assessed before and after the treatment by using the Cervical Dystonia Impact Profile-58 (CDIP-58) questionnaire. The general HRQoL was assessed by using the Medical Outcomes 36-Item Short Form Health Survey (SF-36), while depressive disorder screening was assessed by using the Center of Epidemiologic Studies-Depression (CES-D) questionnaire. The SF-36 and CES-D questionnaire were administered before treatment and every 3 months before the next injection for a 2-year period.

RESULTS

A total of 20 CD patients were enrolled from January 2013 to December 2015. CDIP-58 showed a significant improvement after long-term injections of Abo-BTX A in all domains (P < 0.001). However, only vitality domain of SF-36, which assessed general HRQoL, showed a significant improvement after long-term injections (P = 0.037). There was no prevalence of depressive disorder in all patients (CES-D score <20) in this study.

CONCLUSION

The Abo-BTX A injections at 3-month intervals over a 2-year period improved the CDIP-58 scores, which assess disease-specific HRQoL, as well as an increased vitality domain of general HRQoL. No patient suffered from depression in this study.

Quality of life in cervical dystonia after treatment with botulinum toxin A: a 24-week prospective study

OBJECTIVE

This study aimed to identify possible improvements in disease-specific health-related quality of life (HRQoL) after multiple injections of botulinum toxin A over 24 weeks in Thai cervical dystonia (CD) patients.

MATERIALS AND METHODS

A 24-week prospective study comparing HRQoL of Thai CD patients before and after multiple injections of botulinum toxin A at 3-month intervals was performed. Disease-specific HRQoL was assessed by using the Cervical Dystonia Impact Profile-58 questionnaire (CDIP-58) and the Craniocervical Dystonia Questionnaire-24 (CDQ-24). General HRQoL was assessed by using the Medical Outcomes' 36-Item Short Form Health Survey (SF-36) and the EuroQoL 5-dimension questionnaire (EQ-5D). All the assessments were performed before and after the 24-week treatment period.

RESULTS

A total of 20 CD patients were enrolled in this study from April to December 2011. CDIP-58 and CDQ-24 scores, which assess disease-specific HRQoL, showed a significant improvement after 24 weeks of treatment by botulinum toxin A (P<0.001). However, EQ-5D and SF-36 scores, which assess general HRQoL, showed no significant improvement after the treatment (P>0.05).

CONCLUSION

CD patients' disease-specific HRQoL improved after being treated with multiple botulinum toxin A injections. However, general HRQoL was not improved.

Reduced Neck Muscle Strength and Altered Muscle Mechanical Properties in Cervical Dystonia Following Botulinum Neurotoxin Injections: A Prospective Study

Objective

To evaluate changes in the strength and mechanical properties of neck muscles and disability in patients with cervical dystonia (CD) during a 12-week period following botulinum neurotoxin (BoNT) injections.

Methods

Eight patients with CD volunteered for this prospective clinical cohort study. Patients had received BoNT injections regularly in neck muscles at three-month intervals for several years. Maximal isometric neck strength was measured by a dynamometer, and the mechanical properties of the splenius capitis were evaluated using two myotonometers. Clinical assessment was performed using the Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) before and at 2, 4, 8, and 12 weeks after the BoNT injections.

Results

Mean maximal isometric neck strength at two weeks after the BoNT injections decreased by 28% in extension, 25% in rotation of the affected side and 17% in flexion. At four weeks, muscle stiffness of the affected side decreased by 17% and tension decreased by 6%. At eight weeks, the muscle elasticity on the affected side increased by 12%. At two weeks after the BoNT injections, the TWSTRS-severity and TWSTRS-total scores decreased by 4.3 and 6.4, respectively. The strength, muscle mechanical properties and TWSTRS scores returned to baseline values at 12 weeks.

Conclusions

Although maximal neck strength and muscle tone decreased after BoNT injections, the disability improved. The changes observed after BoNT injections were temporary and returned to pre-injection levels within twelve weeks. Despite having a possible negative effect on function and decreasing neck strength, the BoNT injections improved the patients reported disability.

Cervical range of motion and strength in 4,293 young male adults with chronic neck pain

PURPOSE

The correlation of cervical biomechanics and neck pain in young patients has, to date, only been described in terms of small cohorts. This study focuses on the correlation of chronic neck pain and cervical biomechanics.

METHODS

Neck pain, cervical range of motion (CROM) and maximal cervical torque were recorded in 746 patients with conservatively treated chronic neck pain and 3,547 participants of physiotherapy training without chronic neck pain aged 16-32 years.

RESULTS

The "neck pain" group had a highly significant (s < 0.001) higher neck disability index (44.7 vs. 10.4%), longer history of neck pain (3.47 vs. 0.59 years), higher pain intensity (VAS 5.93 vs. 0.93), higher pain frequency (VAS 6.98 vs. 1.09). No differences of CROM and maximal torque in the sagittal, frontal and transverse plane were found.

CONCLUSION

This study describes the largest cohort of biomechanical data of the cervical spine in young adult recorded to date. The findings demonstrate that no correlation was found between neck pain, CROM and maximal torque in the study cohort. On this basis, we conclude that the CROM and maximal cervical torque should not be used as indicators to measure the progress of chronic neck pain in physiotherapy training and sports medicine for the young adult.

Higher comorbidity, poor functional status and higher health care utilization in veterans with prevalent total knee arthroplasty or total hip arthroplasty

The objective of this study was to compare comorbidity, functional ability, and health care utilization in veterans with total knee arthroplasty (TKA) or total hip arthroplasty (THA) versus matched control populations. A cohort of veterans using Veterans Affairs (VA) healthcare system reported limitations in six activities of daily living (ADLs; bathing, dressing, eating, walking, transferring, and using the toilet), demographics, and physician-diagnosed comorbidity. VA databases provided healthcare utilization and International Classification of Diseases-9/Common procedure terminology codes for TKA/THA. Patients were classified as: (1) primary TKA; (2) primary THA; (3) combination group (>or=1 procedure); and (4) control veteran population (no THA/TKA). Multivariable regression analyses compared the risk or counts of ADL limitation and in-/out-patient visits. After multivariable adjustment, TKA, THA or combination groups had significantly higher prevalence of the following compared to veteran controls: arthritis, diabetes, or heart disease (p < 0.0001 each), severe (>or=3) ADL limitation (33%, 42%, 42% vs. 24%; p < 0.0001), and annual hospitalization rate (24%, 19%, 26% vs. 16%, p < 0.0001). Annual outpatient surgery visits were more (2.5, 2.3, 2.3 vs. 2, p = 0.01) and risk of any mental health outpatient visit was lower (12%, 11%, 12% vs. 18%, p = 0.0039). All ADLs, except eating, were significantly more limited in arthroplasty groups (p <or= 0.0009). Severe ADL limitation was more prevalent in veterans with arthroplasty than in two age-matched US cohorts: 13.4 times in >or=65 years; and 1.2-, 1.6-, and 4-fold in >or=85, 75-84, and 65-74 years. Poorer function and higher comorbidity and utilization in veterans with TKA/THA suggest that this group is appropriate for interventions targeted at improving function and decreasing utilization.

Maximal voluntary isometric neck strength deficits in adults with whiplash-associated disorders and association with pain and fear of movement

STUDY DESIGN

Controlled laboratory study using a cross-sectional, repeated-measures design.

OBJECTIVES

To quantify maximal voluntary isometric neck forces in healthy subjects and individuals with whiplash-associated disorder (WAD), using an objective measurement system to evaluate the test-retest properties of these strength measurements and to assess the links between neck strength, pain, kinesiophobia, and catastrophizing in patients with WAD.

BACKGROUND

The prognosis of WAD is difficult to predict due to a lack of objective measurement methods and to our limited understanding of the role of psychological factors in the development of chronic WAD symptoms.

METHODS AND MEASURES

Fourteen subjects with chronic WAD grade I or II and an age-matched, healthy group (n = 28) participated in this study. Cervical strength was measured with the Multi-Cervical Unit (MCU) in 6 directions, and pain was measured with a visual analog scale. Individuals in the WAD group completed the Neck Disability Index (NDI), the Tampa Scale for Kinesiophobia (TSK), and the Pain Catastrophizing Scale (PCS).

RESULTS

Significant deficits in strength were observed for the individuals in the WAD group compared to the healthy group, particularly in extension, retraction, and left lateral flexion (P<.05). The MCU demonstrated good intratester reliability for the healthy group (ICC = 0.80-0.92) and the WAD group (ICC = 0.85-0.98), and small standard errors of measurement for both groups. No significant association was found between neck strength and NDI, TSK, and PCS.

CONCLUSION

The MCU demonstrated good test-retest properties for healthy subjects and individuals with WAD. Cervical strength was lower in individuals with WAD; however, the strength deficits were not clearly linked with psychological factors.

Focal dystonia, with special reference to writer's cramp

If focal dystonia affects the hand muscles writer's cramp will result, but also other types of activity when the task involves repetitive movements such as typing and playing the piano. Writer's cramp is described, both simple and dystonic, and also the possibility of genetic causes, especially in the latter group. The characteristics of the electromyogram in this condition are discussed. The possible causes of focal dystonia and writer's cramp are reviewed: both the role of excitatory and inhibitory mechanisms and how these may influence treatment. Various treatments have been tried, and the most effective seems to be the use of botulinum toxin. However, if this does not relieve the symptoms, operations such as stereotactic lesions of the basal ganglia may be justified.