Lower trapezius muscle strength in individuals with unilateral neck pain

Examination of Myofascial Stiffness and Elasticity in the Upper Trapezius Region in Patients with Unilateral Neck Pain: A Cross-Sectional Study

(1) Background: Globally, neck pain is prevalent, affecting around thirty percent of the population annually. To better understand the influence of pain on the myofascial layers, the present study investigated these on the upper trapezius muscle in unilateral, more severe neck pain. (2) Methods: This study was a cross-sectional study. Forty patients (42.2 ± 14.7) with a confirmed diagnosis of unilateral neck pain were examined using durometry and indentometry. This study evaluated the stiffness, elasticity, and pressure pain threshold of both sides of the neck (symptomatic side: SS; healthy side: HS). Furthermore, the range of motion of the cervical spine (lateral flexion, rotation) was quantified using a digital goniometer. (3) Results: A significant lateral discrepancy was observed in stiffness between groups (durometry: SS-33.76 ± 7.78, HS-29.75 ± 7.45, p < 0.001; indentometry: SS-59.73 ± 33.93, HS-4.18 ± 12.69, p = 0.024). In contrast, no differences were found between the comparison sides of the upper trapezius for the parameter's elasticity (SS-0.101 ± 1.09, HS--0.006 ± 0.29, p = 0.416), cervical spine mobility (lateral flexion: SS-37.08 ± 8.15, HS-37.73 ± 7.61, p = 0.559; rotation: SS-73.55 ± 12.37, HS-72.85 ± 11.10, p = 0.660), and algometry (SS-36.41 ± 17.53, HS-37.22 ± 17.00, p = 0.657). (4) Conclusion: Overall, it can be concluded that more severe neck pain unilaterally shows differences in stiffness on the same side. Future research is needed to investigate the links.

Lower trapezius muscle function in people with and without shoulder and neck pain: a systematic review

CONTEXT

Shoulder and neck pain are leading causes of disability worldwide. Rotator cuff pathology has strong associations with such pain and is extensively targeted by healthcare practitioners. A dysfunctional lower trapezius muscle has also been shown to contribute to neck and shoulder pain, yet it is often overlooked.

OBJECTIVES

This systematic review analyzes those with a history of, or who are currently managing, shoulder or neck pain to indicate differences in measures of lower trapezius function when compared to subjects without that pain.

METHODS

Studies with no age restrictions were included in the study. Studies could determine lower trapezius muscle function with any quantifiable measurement tool or clinical assessment. If the study included a control group (no pain) and a comparator group (pain), and if lower trapezius muscle function was assessed in both, the study was typically included. The significance of the lower trapezius muscle function change was summarized in these pain patients. From a final total of 18 studies identified, level of muscle activity, muscle activation, time to onset, muscle strength, and muscle thickness were reported.

RESULTS

The 18 included articles involved 485 participants with shoulder and/or neck pain and 455 without. Half of the shoulder pain studies (6/12), and all of the neck pain studies (6/6), demonstrated that the lower trapezius had a noticeable impact. The lower trapezius muscle in participants with shoulder and neck pain tended to show decreased muscle strength, and decreased time to onset/latency.

CONCLUSIONS

The findings from this systematic review should be taken into consideration when assessing and treating patients with shoulder and neck pain. Future studies that define the type and duration of shoulder and neck pain, as well as prospectively assessing lower trapezius muscle function in those with and without that pain, are needed.

Cervical and scapula-focused resistance exercise program versus trapezius massage in patients with chronic neck pain: A randomized controlled trial

OBJECTIVE

The purpose of this study was to investigate the effects of resistance exercise in comparison with those of common exercise on chronic neck pain (CNP) to provide useful clinical guidelines for reducing pain or increasing cervical range of motion (ROM), upper trapezius tone, disability level, and quality of life (QOL).

METHODS

The subjects were randomized into a cervical and scapula-focused resistance exercise group (CSREG, n = 21) or trapezius massage group (TMG, n = 20). All groups received a 4-week, five times per week CSRE or TM program for CNP. The visual analogue scale (VAS) score, cervical ROM, myotonometer measures (upper trapezius tone, stiffness, and elasticity), neck disability index (NDI), and short form-36 (SF-36) were identified as the primary outcomes.

RESULTS

Within-group changes in VAS, cervical ROM, myotonometer measures, NDI, and SF-36 were significant in the CSREG and TMG (P < .05). The between-group changes in VAS, cervical rotation, myotonometer (upper trapezius tone and stiffness), NDI, and SF-36 after intervention showed significant differences between the CSREG and TMG (P < .05).

CONCLUSION

These results suggest that the CSRE program is effective in improving pain, cervical ROM, upper trapezius tone, disability level, and QOL in patients with CNP. More comprehensive studies with longer follow-up durations are needed to better understand the potential effects of the CSRE program in patients with CNP.

Influencing factors of pressure pain hypersensitivity of the upper trapezius in food service workers with nonspecific neck/shoulder myofascial pain: A cross-sectional study

It is unclear which factors contribute to the developing pressure pain hypersensitivity of the upper trapezius, a type of neurophysiological hyperexcitability. The present study investigated the relationship between physical and psychological factors and pressure pain hypersensitivity of the upper trapezius for each sex. In total, 154 individuals with neck/shoulder myofascial pain participated, among 372 food service workers. Participants completed a questionnaire (Beck Depression Inventory, and Borg Rating of Perceived Exertion scale) and were photographed to measure posture. Pressure pain sensitivity, 2 range of motions (cervical lateral bending and rotation), and 4 muscle strengths (serratus anterior, lower trapezius [LT], biceps, and glenohumeral external rotator) were measured by a pressure algometer, iPhone application, and handheld dynamometer, respectively. For each sex, forward multivariate logistic regression was used to test our a priori hypothesis among selected variables that a combination of psychosocial and physical factors contributed to the risk for pressure pain hypersensitivity. In multivariate analyses, LT strength (odds ratio = 0.94, 95% confidence interval = 0.91-0.97, P = .001) was the only significant influencing factor for pressure pain hypersensitivity in men. Dominant painful ipsilateral cervical rotation range of motion (odds ratio = 0.96, 95% confidence interval = 0.92-0.99, P = .037) was the only influencing factor for pressure pain hypersensitivity in women. LT strength and dominant painful ipsilateral cervical rotation range of motion could serve as guidelines for preventing and managing pressure pain hypersensitivity of the upper trapezius in food service workers with nonspecific neck/shoulder myofascial pain.

Twelve-Week Lower Trapezius-Centred Muscular Training Regimen in University Archers

Archery is a fine-motor-skill sport, in which success results from multiple factors including a fine neuromuscular tuning. The present study hypothesised that lower trapezius specific training can improve archers’ performance with concomitant changes in muscle activity and shoulder kinematics. We conducted a prospective study in a university archery team. Athletes were classified into exercise and control groups. A supervised lower trapezius muscle training program was performed for 12 weeks in the exercise group. The exercise program focused on a lower trapezius-centred muscular training. Performance in a simulated game was recorded as the primary outcome, and shoulder muscle strength, kinematics, and surface electromyography were measured and analysed. In the exercise group, the average score of the simulation game increased from 628 to 639 after the training regimens (maximum score was 720), while there were no such increases in the control group. The lower trapezius muscle strength increased from 8 to 9 kgf after training regimens and shoulder horizontal abductor also increased from 81 to 93 body weight% for the exercise group. The upper/lower trapezius ratio decreased from 2.2 to 1.1 after training. The lower trapezius exercise training regimen could effectively improve the performance of an archer with a simultaneous increase in shoulder horizontal abductor and lower trapezius muscle strength.

Trapezius and serratus anterior muscle strength in violinists with unilateral neck pain

BACKGROUND

Weakness of the trapezius and serratus anterior (SA) muscle may be a risk factor for unilateral neck pain.

OBJECTIVE

This study examined the trapezius (upper, middle, and lower) and SA muscle strength ipsilateral and contralateral to the painful side in violinists with unilateral neck pain.

METHOD

Twenty-six female violinists with unilateral neck pain participated in this study. Participants reported the pain intensity and duration and completed the Neck Disability Index (NDI). The strengths of the upper (UT), middle (MT), and lower (LT) trapezius and SA muscles were measured using a handheld dynamometer. Paired t-test was used to compare the strength of the muscles between ipsilateral and contralateral to the painful side within subjects. The relationship between pain intensity, pain duration, and neck disability and strength deficit of the muscle was demonstrated by Pearson's correlation and Spearman's rank correlation.

RESULTS

The strengths of the UT, MT, LT, and SA muscles were significantly decreased on the painful side compared with the contralateral side (P< 0.05). Except for correlations between pain intensity and percent strength deficit of the UT and between pain duration and percent strength deficit of the MT (P< 0.05), there were no significant associations between pain intensity, pain duration, or NDI and the percent strength deficit of the UT, MT, LT and SA muscles (P> 0.05).

CONCLUSIONS

These results suggest that decreased UT, MT, LT, and SA muscle strength on the side of the pain should be considered in the rehabilitation of violinists with unilateral neck pain.

Differences in the activity of the shoulder girdle and lower back muscles owing to postural alteration while using a smartphone

The purpose of this study was to clarify the influence of different postures on the activity of the shoulder girdle and lower back muscles while using a smartphone. Sixteen healthy male participants maintained two postures while using a smartphone : a good posture in which the tragus and acromion were closer to the vertical line passing through the greater trochanter, and a poor posture in which the tragus and acromion were farther from the vertical line passing through the greater trochanter. The target muscles were the rhomboid major (Rhom), upper trapezius, middle trapezius, lower trapezius (LT), lumbar erector spinae (LES), and lumbar multifidus (LMF). The activities of the Rhom and LT were significantly lower with poor posture than those with good posture. The activities of LES and LMF were significantly higher with poor posture than those with good posture. The results of this study indicated that poor posture was associated with hypoactivity of the shoulder girdle muscles and hyperactivity of the lower back muscles when compared with good posture. Poor posture for prolonged periods while using a smartphone would lead to malfunction of the shoulder girdle muscles and musculofascial lower back pain. J. Med. Invest. 67 : 274-279, August, 2020.

Examination of Regional Interdependence Theory in Chronic Neck Pain: Interpretations from Correlation of Strength Measures in Cervical and Pain-Free Regions

OBJECTIVE

Impairments present in chronic pain conditions have been reported not to be limited to the painful region. Pain-free regions have also been proposed to be adversely affected as a cause or consequence of the painful condition. The aim of this study was to investigate the association between muscle strength in painful and pain-free regions and chronic neck pain.

DESIGN

A cross-sectional study.

SETTING

Rehabilitation hospital laboratory.

SUBJECTS

One hundred twenty-two patients with chronic neck pain (87 female) and 98 asymptomatic volunteers (52 female) were included in the study.

METHODS

Maximal isometric strength measures of the neck, scapulothoracic, shoulder, trunk, and hip muscles were assessed using a hand-held dynamometer in all participants. Pain intensity and pain-related disability were also assessed in patients through visual analog scale and Neck Disability Index scores, respectively.

RESULTS

Principal component analysis revealed one component for each of the studied regions. Multivariate analysis of variance found neck (d = 0.46), scapulothoracic (d = 0.46), shoulder (d = 0.60), trunk flexor (d = 0.38), extensor (d = 0.36), and hip (d = 0.51) strength components to be lower in the neck pain patients compared with asymptomatic participants (P < 0.01). Logistic and linear regression analyses found the shoulder strength component both to be a significant predictor for neck pain occurrence (β = 0.53, P < 0.01) and to have a considerable effect on pain intensity score (β=-0.20, P = 0.02), respectively.

CONCLUSIONS

The results found that some pain-free regions in addition to the cervical spine to exhibit lower levels of muscular strength in neck pain patients. These findings support the regional interdependence theory, which proposes that impairments are not limited to the painful area and are possibly mediated by central mechanisms.

Local and Widespread Pressure Pain Hyperalgesia Is Not Side Specific in Females with Unilateral Neck Pain that Can Be Reproduced during Passive Neck Rotation

Current evidence for widespread hyperalgesia in non-specific neck pain (NSNP) is unclear. It is currently recommended to group NSNP patients according to pain-provoking movements. The aim of this study was to investigate local and widespread pain sensitivity in females with unilateral NSNP that is reproducible during passive neck rotation compared with matched controls, and to compare the side specific effect of pain location on pressure pain sensitivity among females with unilateral NSNP. Thirty-six females with unilateral NSNP evoked during passive ipsilateral (n = 20) or contralateral (n = 16) rotation toward the painful side were compared with 20 controls. Participants reported their pain intensity at rest and during passive neck rotation and completed the Neck Disability Index. Pressure pain thresholds (PPTs) were assessed bilaterally over the anterior scalene; the sternocleidomastoid; the levator scapulae; lateral to the spinous process of C6; the median, ulnar, and radial nerves; and the tibialis anterior. The ANOVA revealed lower PPTs in females with unilateral NSNP compared with the controls (all at p < 0.001), but no differences were found between the sides, nor was there any Group × side interaction. Among females with NSNP, those with higher pain intensity during ipsilateral rotation toward the painful side showed lower PPTs over the anterior scalene, median nerve, ulnar nerve, and tibialis anterior (all, p < 0.05) than females with higher pain intensity during contralateral rotation toward the painful side. These findings demonstrated bilateral local and widespread pressure pain hyperalgesia in females with unilateral NSNP that was reproducible during passive neck rotation compared with controls. There was no side specific effect of pain location on PPTs among females with unilateral NSNP.

A Comparison Between the Effects of Scapulothoracic Mobilization Plus Physical Therapy With Physical Therapy Alone in Patients With Mechanical Neck Pain: A Randomized Clinical Trial

Objective

The purpose of this study was to compare the effects of scapulothoracic (ST) mobilization plus physical therapy (PT) with PT alone in patients with mechanical neck pain.

Methods

This double-blinded randomized clinical trial was conducted at Shiraz School of Rehabilitation Sciences and involved 46 patients with mechanical neck pain and scapular dyskinesia. The patients were randomly assigned to the ST mobilization + PT group (scapulothoracic mobilization and physical therapy) or the PT group (physical therapy treatment) by a computer-generated randomized table of numbers. Both groups received 5 sessions of treatment during 1 week. Pain intensity and grip strength were evaluated 3 times: baseline, after the first session, and after the fifth session. Furthermore, functional disability of the upper limbs and the neck were evaluated before and at the fifth session.

Results

The results showed that the pain intensity was reduced and grip strength increased significantly after the first session (P = .01) and at the end of the treatment (P = .01) in the ST mobilization + PT group in comparison with the PT group. Also, the mean difference of upper limb (P = .01) and neck disability (P = .02) decreased significantly in the ST mobilization + PT group in comparison with the PT group.

Conclusion

Scapulothoracic mobilization in combination with physical therapy may be superior to physical therapy alone in reducing pain intensity, maximizing grip strength, and reducing upper limb and neck disability in mechanical neck pain.

Predictors of upper trapezius pain with myofascial trigger points in food service workers: The STROBE study

Shoulder pain occurs commonly in food service workers (FSWs) who repetitively perform motions of the upper limbs. Myofascial trigger points (MTrPs) on the upper trapezius (UT) are among the most common musculoskeletal shoulder pain syndromes. This study determined the psychological, posture, mobility, and strength factors associated with pain severity in FSWs with UT pain due to MTrPs.In this cross-sectional study, we measured 17 variables in 163 FSWs with UT pain due to MTrPs: a visual analog scale (VAS) pain score, age, sex, Borg rating of perceived exertion (BRPE) scale, beck depression inventory, forward head posture angle, rounded shoulder angle (RSA), shoulder slope angle, scapular downward rotation ratio, cervical lateral-bending side difference angle, cervical rotation side difference angle, glenohumeral internal rotation angle, shoulder horizontal adduction angle, serratus anterior (SA) strength, lower trapezius (LT) strength, bicep strength, and glenohumeral external rotator strength, in 163 FSWs with UT pain due to MTrPs.The model for factors influencing UT pain with MTrPs included SA strength, age, BRPE, LT strength, and RSA as predictor variables that accounted for 68.7% of the variance in VAS (P < .001) in multiple regression models with a stepwise selection procedure. The following were independent variables influencing the VAS in the order of standardized coefficients: SA strength (β = -0.380), age (β = 0.287), BRPE (β = 0.239), LT strength (β = -0.195), and RSA (β = 0.125).SA strength, age, BRPE, LT strength, and RSA variables should be considered when evaluating and intervening in UT pain with MTrPs in FSWs.

Scapulothoracic muscle strength in individuals with neck pain

BACKGROUND

People with neck pain often present with weakness in the scapulothoracic muscles. Few studies have examined lower trapezius (LT), middle trapezius (MT) and serratus anterior (SA) muscle strength in individuals with neck pain, nor compared strength to asymptomatic individuals.

OBJECTIVES

The aim of this study was to examine LT, MT and SA muscle strength in individuals with chronic neck pain.

METHODS

Descriptive cross sectional design. Twenty two individuals with chronic neck pain and 17 asymptomatic individuals were included. Participants were asked to complete a screening questionnaire, Neck Disability Index, and underwent manual muscle testing for the LT, MT, and SA muscles bilaterally. Data analyses included paired and comparative independent t-tests.

RESULTS

For individuals with neck pain, significant within subject differences in strength between sides for the LT (P< 0.01) and MT (P< 0.01) were present. In contrast, no within subject difference between sides for the asymptomatic group was found for any muscle. Individuals with neck pain were significantly weaker than asymptomatic individuals for the LT (p= 0.02), MT (p= 0.03), and SA (p= 0.01) on their side of neck pain, but not on their non-painful side.

CONCLUSIONS

Significant within subject differences were found between sides for the LT and MT while significant between group differences were identified for all three muscles tested.

A Comparison of the Effects of Stabilization Exercises Plus Manual Therapy to Those of Stabilization Exercises Alone in Patients With Nonspecific Mechanical Neck Pain: A Randomized Clinical Trial

STUDY DESIGN

Randomized clinical trial.

BACKGROUND

Little is known about the efficacy of providing manual therapy in addition to cervical and scapulothoracic stabilization exercises in people with mechanical neck pain (MNP). Objectives To compare the effects of stabilization exercises plus manual therapy to those of stabilization exercises alone on disability, pain, range of motion (ROM), and quality of life in patients with MNP.

METHODS

One hundred two patients with MNP (18-65 years of age) were recruited and randomly allocated into 2 groups: stabilization exercise without (n = 51) and with (n = 51) manual therapy. The program was carried out 3 days per week for 4 weeks. The Neck Disability Index, visual analog pain scale, digital algometry of pressure pain threshold, goniometric measurements, and Medical Outcomes Study 36-Item Short-Form Health Survey were used to assess participants at baseline and after 4 weeks.

RESULTS

Improvements in Neck Disability Index score, night pain, rotation ROM, and the Medical Outcomes Study 36-Item Short-Form Health Survey score were greater in the group that received stabilization exercise with manual therapy compared to the group that only received stabilization exercise. Between-group differences (95% confidence interval) were 2.2 (0.1, 4.3) points for the Neck Disability Index, 1.1 (0.0, 2.3) cm for pain at night measured on the visual analog scale, -4.3° (-8.1°, -0.5°) and -5.0° (-8.2°, -1.7°) for right and left rotation ROM, respectively, and -2.9 (-5.4, -0.4) points and -3.1 (-6.2, 0.0) points for the Medical Outcomes Study 36-Item Short-Form Health Survey physical and mental components, respectively. Changes in resting and activity pain, pressure pain threshold, and cervical extension or lateral flexion ROM did not differ significantly between the groups. Pressure pain threshold increased only in those who received stabilization exercise with manual therapy (P<.05).

CONCLUSION

The results of this study suggest that stabilization exercises with manual therapy may be superior to stabilization exercises alone for improving disability, pain intensity at night, cervical rotation motion, and quality of life in patients with MNP.

LEVEL OF EVIDENCE

Therapy, level 1b.

Scapulothoracic Muscle Strength Changes Following a Single Session of Manual Therapy and an Exercise Programme in Subjects with Neck Pain

INTRODUCTION

Scapulothoracic muscle weakness has been associated with neck pain (NP). Little evidence exists regarding lower trapezius (LT), middle trapezius (MT) and serratus anterior (SA) strength in this population. LT strength changes have been observed following thoracic manipulation in healthy subjects. The purpose of the present study was to examine scapulothoracic strength changes following cervical manipulation in subjects with NP.

METHODS

Twenty-two subjects with NP and 17 asymptomatic control (AC) subjects underwent strength testing of the LT, MT and SA using a hand-held dynamometer. Subjects with NP were treated with passive intervertebral neck manipulation and neck range of motion exercises. The AC group received no intervention. Strength testing was repeated after manipulation, then 48 and 96 hours later. Change scores were calculated for strength over time. Paired t-tests were done for strength change between painful and non-painful sides in the NP group. Independent t-tests were done for strength change between the NP group and AC group.

RESULTS

There was no significant difference between groups for age, gender, hand dominance or body mass index. Mean (standard deviation) symptom duration for subjects in the NP group was 43.27 (62.71) months. There was no significant difference in strength change over time between painful and non-painful sides in the NP group for any muscle; however, there was a significant difference in strength change over time between those in the NP group and AC group for the LT (p < 0.01), SA (p < 0.01) and MT (p < 0.01).

DISCUSSION

Scapulothoracic muscle strength improvements were observed in both extremities following passive intervertebral neck manipulation and neck range of motion exercises. Improvements lasted up to 96 hours following manipulation, even though no strengthening exercises were prescribed.

CONCLUSIONS

Manipulation and range of motion should be considered as a component of intervention programmes for patients with NP and scapulothoracic muscle weakness. Future studies should compare manipulation alone to exercise alone to determine impact on strength. Copyright © 2016 The Authors Musculoskeletal Care Published by John Wiley & Sons Ltd.

Decreased thickness of the lower trapezius muscle in patients with unilateral neck pain

INTRODUCTION

Thickness of the lower trapezius muscle in patients with neck pain has not been established. We examined the thickness of the lower trapezius muscle in patients with and without unilateral neck pain.

METHODS

Twenty women with unilateral (right) neck pain and 20 matched controls participated in the study. Thickness of the lower trapezius muscles was measured bilaterally at rest (0 ° and 120 ° of shoulder abduction) and during contraction (120 ° of shoulder abduction) using ultrasound imaging.

RESULTS

The neck pain group had smaller thickness of the lower trapezius muscle on the painful side compared with controls both at rest and during contraction (P < 0.05). However, the percentage change in the lower trapezius thickness from rest to contraction (120 ° of shoulder abduction) was not different between groups (P > 0.05).

CONCLUSIONS

Patients with neck pain had smaller thickness of the lower trapezius muscle on the painful side compared with healthy controls. Muscle Nerve 54: 439-443, 2016.

A slouched body posture decreases arm mobility and changes muscle recruitment in the neck and shoulder region

PURPOSE

Long-term use of unfavorable postures, congenital deformations and degenerative processes associated with aging or disease may generate an increased thoracic curvature resulting in pain and disability. We wanted to examine whether a slouched postural alignment with increased thoracic kyphosis changes the shoulder kinematics and muscle activity in upper trapezius (UT), lower trapezius (LT) and serratus anterior (SA) during arm elevation. The aim was to determine if a slouched posture influences range of motion, muscle activation patterns, maximal muscle activity and the total muscle work required when performing arm elevations.

METHOD

Twelve male subjects (23.3 ± 1.5 years) performed maximum arm elevations in upright and slouched postures. A combined 3D movement and EMG system recorded arm movements and spine curvature simultaneously with EMG activity in the UT, LT and SA.

RESULTS

Slouched posture affected the biomechanical conditions by significantly decreasing maximum arm elevation by ~15° (p < 0.001) and decreasing arm movement velocity by ~8 % during movements upwards (p < 0.001) and downwards (p = 0.034). The peak muscle activity increased in all muscles: UT (p = 0.034, +32.3 %), LT (p = 0.001, +48.6 %) and SA (p = 0.007, +20.9 %). The total muscle work increased significantly in the slouched posture during movements upwards: UT (p = 0.003, +36.6 %), LT (p < 0.001, +89.0 %), SA (p = 0.002, +19.4 %) and downwards: UT (p = 0.012, +29.8 %) and LT (p < 0.001, +122.5 %).

CONCLUSION

An increased thoracic kyphosis was found associated with marked increased physical costs when performing arm movements. Hence, patients suffering from neck-shoulder pain and disability should be investigated and treated for defective thoracic curvature issues.

Effectiveness of dry needling on the lower trapezius in patients with mechanical neck pain: a randomized controlled trial

OBJECTIVE

To evaluate the effect of dry needling into a myofascial trigger point (MTrP) in the lower trapezius muscle of patients with mechanical idiopathic neck pain.

DESIGN

A single-center, randomized, double-blinded controlled study.

SETTING

Patients were recruited from the student population of a local hospital by advertisement in the university clinic from January 2010 to December 2011.

PARTICIPANTS

Patients (N=72) with unilateral neck pain, neck pain for ≥3 months, and active trigger points in the lower trapezius muscle were randomly assigned to 1 of 2 treatment groups. All the patients completed the study.

INTERVENTIONS

Dry needling in an MTrP in the lower trapezius muscle, or dry needling in the lower trapezius muscle but not at an MTrP.

MAIN OUTCOME MEASURES

The visual analog scale (VAS), Neck Pain Questionnaire (NPQ), and pressure-pain threshold (PPT) were assessed before the intervention and 1 week and 1 month postintervention.

RESULTS

Treatment with dry needling of the lower trapezius muscle close to the MTrP showed decreases in pain and PPT as well as an improvement in the degree of disability (P<.001) compared with the baseline and control group measurements (P<.001). The dry-needling technique performed in the MTrP showed more significant therapeutic effects (P<.001).

CONCLUSIONS

The application of dry needling into an active MTrP of the lower trapezius muscle induces significant changes in the VAS, NPQ, and PPT levels compared with the application of dry needling in other locations of the same muscle in patients with mechanical neck pain.

Intraexaminer reliability of hand-held dynamometry in the upper extremity: a systematic review

OBJECTIVE

To summarize and appraise the literature on the intraexaminer reliability of hand-held dynamometry (HHD) in the upper extremity.

DATA SOURCES

MEDLINE, CINAHL, and EMBASE were searched for relevant studies published up to December 2011. In addition, experts were contacted, and journals and reference lists were hand searched.

STUDY SELECTION

To be included in the review, articles needed to (1) use a repeated-measures, within-examiner(s) design; (2) include symptomatic or asymptomatic individuals, or both; (3) use HHD to measure muscle strength in any of the joints of the shoulder, elbow, or wrist with the "make" or the "break" technique; (4) report measurements in kilogram, pound, or torque; (5) use a device that is placed between the examiner's hand and the subject's body; and (6) present estimates of intraexaminer reliability.

DATA EXTRACTION

Quality assessment and data extraction were performed by 2 reviewers independently.

DATA SYNTHESIS

Fifty-four studies were included, of which 26 (48%) demonstrated acceptable intraexaminer reliability. Seven high-quality studies showed acceptable reliability for flexion and extension of the elbow in healthy subjects. Conflicting results were found for shoulder external rotation and abduction. Reliability for all other movements was unacceptable. Higher estimates were reached for within-sessions reliability and if means of trials were used.

CONCLUSIONS

Intraexaminer reliability of HHD in upper extremity muscle strength was acceptable only for elbow measurements in healthy subjects. We provide specific recommendations for future research. Physical therapists should not rely on HHD measurements for evaluation of treatment effects in patients with upper extremity disorders.

The relevance of scapular dysfunction in neck pain: a brief commentary

Synopsis Though our understanding of motor disorders and mechanical neck pain has advanced, the role of scapular dysfunction in mechanical neck pain remains enigmatic. The biomechanical interdependence between the neck and scapula and the potentially deleterious consequences of scapular dysfunction in the cervical region are biomechanically plausible. Yet the relevance of observed scapular dysfunction in patients with neck pain is still inadequately explained by research. However, studies investigating the association between scapular function and neck pain are beginning to emerge. The purpose of this paper was to review the current knowledge of this topic and consider the implications for clinical practice. Level of Evidence Therapy, level 5.

Isometric shoulder strength reference values for physically active collegiate males and females

Background:

It is common clinical practice to assess muscle strength during examination of patients following shoulder injury or surgery. Strength comparisons are often made between the patient’s injured and uninjured shoulders, with the uninjured side used as a reference without regard to upper extremity dominance. Despite the importance of strength measurements, little is known about expected normal baselines of the uninjured shoulder. The purpose of this study was to report normative values for isometric shoulder strength for physically active college-age men and women without history of shoulder injury.

Methods:

University students—546 males (18.8 ± 1.0 years, 75.3 ± 12.2 kg) and 73 females (18.7 ± 0.9 years, 62.6 ± 7.0 kg)—underwent thorough shoulder evaluations by an orthopaedic surgeon and completed bilateral isometric strength measurements with a handheld dynamometer. Variables measured included internal rotation, external rotation, abduction, supine internal rotation and external rotation at 45°, and lower trapezius in prone flexion.

Results:

Significant differences were found between the dominant and nondominant shoulder for internal rotation, internal rotation at 45°, abduction, and prone flexion in males and in internal rotation at 45° and prone flexion for females (P ≤ 0.01).

Upper extremity strength characteristics in female recreational tennis players with and without lateral epicondylalgia

STUDY DESIGN

Descriptive, cross-sectional.

OBJECTIVES

To compare static strength characteristics of the upper extremity musculature in female recreational tennis players with lateral epicondylalgia to those of nonsymptomatic tennis players and a control group of women who did not play tennis.

BACKGROUND

There is a paucity of research describing the relationship between lateral epicondylalgia and strength characteristics of the upper extremity musculature, despite the functional relationship between the shoulder, elbow, and wrist.

METHODS

Sixty-three women were recruited into 3 groups (n = 21 per group): symptomatic tennis players (STP) with lateral epicondylalgia, nonsymptomatic tennis players, and controls. Data collection was performed during a single session, during which the strength of selected muscle groups of the dominant upper extremity was measured using a combination of force transducers. Strength ratios of selected muscle groups were then calculated.

RESULTS

The STP group reported median pain level of 3/10 on a numeric pain rating scale and a symptom duration of 16 weeks. The STP group had weaker lower trapezius strength (mean difference, -9.0 N; 95% confidence interval [CI]: -13.5, -4.4) and wrist extensor strength (-12.7 N; 95% CI: -24.4, -1.1), and a higher shoulder internal/external rotation strength ratio (0.19; 95% CI: 0.02, 0.35) and upper/lower trapezius strength ratio (1.32; 95% CI: 0.41, 2.23), compared to those of the nonsymptomatic group. Compared to the control group, the STP group demonstrated a significantly higher shoulder internal/external rotation strength ratio (0.21; 95% CI: 0.04, 0.38) and wrist flexion/extension strength ratio (0.14; 95% CI: 0.01, 0.27).

CONCLUSION

In this group of recreational female tennis players, significant differences in strength and strength ratio characteristics were identified. Although the design of the study precludes establishing a cause-and-effect relationship, the results suggest further study and treatment of the muscle groups of interest.

Reliability and group differences in quantitative cervicothoracic measures among individuals with and without chronic neck pain

Background

Clinicians frequently rely on subjective categorization of impairments in mobility, strength, and endurance for clinical decision-making; however, these assessments are often unreliable and lack sensitivity to change. The objective of this study was to determine the inter-rater reliability, minimum detectable change (MDC), and group differences in quantitative cervicothoracic measures for individuals with and without chronic neck pain (NP).

Methods

Nineteen individuals with NP and 20 healthy controls participated in this case control study. Two physical therapists performed a 30-minute examination on separate days. A handheld dynamometer, gravity inclinometer, ruler, and stopwatch were used to quantify cervical range of motion (ROM), cervical muscle strength and endurance, and scapulothoracic muscle length and strength, respectively.

Results

Intraclass correlation coefficients for inter-rater reliability were significantly greater than zero for most impairment measures, with point estimates ranging from 0.45 to 0.93. The NP group exhibited reduced cervical ROM (P ≤ 0.012) and muscle strength (P ≤ 0.038) in most movement directions, reduced cervical extensor endurance (P = 0.029), and reduced rhomboid and middle trapezius muscle strength (P ≤ 0.049).

Conclusions

Results demonstrate the feasibility of obtaining objective cervicothoracic impairment measures with acceptable inter-rater agreement across time. The clinical utility of these measures is supported by evidence of impaired mobility, strength, and endurance among patients with NP, with corresponding MDC values that can help establish benchmarks for clinically significant change.