Passive Shoulder External Rotation Research Articles

The Clinical Utility of the Seated Wall Angel as a Test with Scoring.

The seated wall angel (SWA) is an intervention to improve upper quarter mobility but has not been described as a clinical test with scoring. To explore the clinical utility of the SWA as a test with scoring. The authors hypothesized that SWA test scores would be lower on the injured than uninjured side, improve over time, and show stronger association with patient-reported shoulder function than shoulder mobility tests. Prospective cohort. Patients diagnosed with anterior shoulder instability and referred to physical therapy participated. Testing occurred after physical therapy examination (initial) and six weeks later (follow-up). Rehabilitation was not controlled. Testing included clinical tests (SWA, passive shoulder external rotation range of motion, total arc of motion) and patient-reported outcomes including the American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form, (ASES) and the Western Ontario Shoulder Instability Index (WOSI). The SWA test was scored 0 to 3 points bilaterally based on number of body contacts with the wall (i.e., elbows and fingertips, posterior fingers, posterior forearm). Passive range of motion was measured with a standard goniometer. SWA scores were compared between sides at initial testing and compared between testing timepoints on the injured side. Associations among injured side clinical test values and patient-reported outcome scores were examined. Mean (SD) SWA score on the injured side was significantly lower than the uninjured side at initial testing [1.6 (1.0) vs 2.2 (1.1), p = 0.045] and significantly increased at follow-up testing [2.4 (1.0), p = 0.041]. Only SWA test score was significantly correlated with ASES (r=0.597) and WOSI (r=-0.648) scores at initial testing, and SWA test score was significantly correlated with WOSI score at follow-up testing (r=-0.611). The clinical utility of the SWA test is supported by distinguishing the injured and uninjured sides and having stronger associations with patient-reported shoulder function than shoulder mobility tests.

Defining the glenohumeral range of motion required for overhead shoulder mobility: an observational study.

Recovery of overhead mobility after shoulder surgery is time-consuming and important for patient satisfaction. Overhead stretching and mobilization of the scapulothoracic and glenohumeral (GH) joints are common treatment interventions. The isolated GH range of motion (ROM) of flexion, abduction, and external rotation required to move above 120° of global shoulder flexion in the clinical setting remains unclear. This study clarified the GH ROM needed for overhead mobility. The timely development of shoulder ROM in patients after shoulder surgery was analyzed. Passive global shoulder flexion, GH flexion, abduction, and external rotation ROM were measured using goniometry and visually at 2-week intervals starting 6-week postsurgery until the end of treatment. Receiver operating characteristic curves were used to identify the GH ROM cutoff values allowing overhead mobility. A total of 21 patients (mean age 49 years; 76% men) after rotator cuff repair (71%), Latarjet shoulder stabilization (19%), and arthroscopic biceps tenotomy (10%) were included. The ROM cutoff value that accurately allowed overhead mobility was 83° for GH flexion and abduction with the area under the curve (AUC) ranging from 0.90 to 0.93 (p < 0.001). The cutoff value for GH external rotation was 53% of the amount of movement on the opposite side (AUC 0.87, p < 0.001). Global shoulder flexion above 120° needs almost full GH flexion and abduction to be executable. External rotation ROM seems less important as long as it reaches over 53% of the opposite side.

Permanent Brachial Plexus Birth Injury: Helsinki Shoulder Protocol.

Passive shoulder exercises from birth and ultrasound screening from 3 to 12 months. Botox is given to shoulder internal rotators and a bracing commenced, if alpha-angle exceeds 30°, or passive shoulder external rotation is below 70 degrees. Plexus reconstruction is recommended to children with root avulsion(s) on magnetic resonance imaging or 3-month Toronto Test Score < 3.5. Specific neurotization is recommended to children without avulsions, but lack of progress in healing. Shoulder dysplasia was diagnosed in 49% of 270 patients with permanent brachial plexus birth injury in our catchment area from 1995 to 2021. The age at detection of shoulder dysplasia dropped from mean 5.4 years in children born before 2000 to mean 3.9 months in children born after 2009. Botox was given to 57% of the patients born after 2009. Rate of shoulder relocation decreased from 28 to 7% while mean active shoulder external rotation in adduction increased from 2 to 46°.

The Relationship Between Frailty and Functional Outcomes, Range of Motion, and Reoperation After Reverse Total Shoulder Arthroplasty for Proximal Humerus Fracture.

The objective of this study was to investigate whether frailty is associated with functional outcomes, motion, and reoperation at a minimum of 2 years after reverse total shoulder arthroplasty (rTSA) for proximal humerus fracture. We performed a retrospective study of 153 patients who underwent rTSA for proximal humerus fracture at two level 1 trauma centers from 2003 to 2018 with minimum 2-year follow-up. Frailty was assessed using the modified 5-item frailty index (mFI). The primary outcome variable was the American Shoulder and Elbow Surgeons (ASES) shoulder score at minimum 2-year follow-up. The secondary outcome variables were the Shoulder Pain and Disability Index (SPADI), the Shoulder Subjective Value (SSV), the 0 to 10 numeric rating scale (NRS) pain score, surgical complication, and reoperation. Bivariate comparisons were made between mFI and outcome variables. The mean age of the 153 patients was 70 years, and 76% were women. Forty patients (26%) had a mFI score of 0, 65 patients (42%) had a mFI score of 1, 40 patients (26%) had a mFI score of 2, and 8 patients (5%) had a mFI score of 3. Twenty-seven patients (18%) had complications, and 21 patients (14%) underwent reoperation. At minimum 2-year follow-up, mFI was not associated with ASES shoulder score, SPADI, SPADI pain or disability subscales, SSV, NRS pain score, active and passive shoulder forward flexion, abduction, and external rotation, complication, or reoperation. Provided they survive the initial physiologic insults of trauma and surgery, patients with higher mFI scores treated with rTSA for proximal humerus fracture can expect similar medium-term restoration of shoulder function. [Orthopedics. 2023;46(5):274-279.].

Understanding frozen shoulder in the hemiparetic arm after stroke

Frozen shoulder is more common in the weakened hemiparetic shoulder post stroke than in the general population. Increasing age, micro-vascular co-morbidities and the presence of subluxation make the soft tissue of the hemiparetic shoulder more susceptible to injury and inflammation. Inflammation can trigger fibrosis of the shoulder ligamentous capsule due to a disruption of joint homeostasis. It is this fibrosis that results in the common presenting features of frozen shoulder, namely restriction of passive shoulder external rotation, abduction and internal rotation. Spasticity of shoulder adductors and internal rotators is also common in hemiparesis and is hard to differentiate from frozen shoulder. Diagnostic lateral pectoralis nerve blocks (DNBs) may help to differentiate between the two. However, several muscles often contribute to shoulder adductor and internal rotator spasticity, so there is a risk of false positives with DNBs. Frozen shoulder is still largely a clinical diagnosis after assessment and exclusion of other possibilities. In cases of Frozen shoulder, daily movements of the shoulder joint within tolerable pain limits can help to restore joint homeostasis and lead to reduced pain. Steroid injection (either alone or as part of a hydrodilatation injection) when inflammation is present can also reduce pain and improve range when used in combination with physiotherapy.

Clinical shoulder measurements related to joint loads in collegiate pitchers

Pitchers are prone to upper extremity injury due to repetitive high joint loads. Clinical measures of shoulder strength and range of motion (ROM) have shown links to injury risk in pitchers, however, these factors have rarely been studied in relation to throwing joint loads. The purpose of this study was to identify which clinical ROM and isokinetic strength variables were related to peak shoulder and elbow joint torques in collegiate pitchers. Thirty-three healthy collegiate pitchers participated in this study. Fastball velocity, shoulder concentric and eccentric strength, and passive shoulder ROM variables were analyzed using a Lasso regression to determine what factors influenced shoulder internal rotation torque and elbow varus torque. Fastball velocity was selected by the Lasso as indicator of increased shoulder and elbow torque. Passive shoulder external rotation ROM was also selected as an important factor in joint loading with increased shoulder external rotation ROM being related to lower joint loads. The bilateral ratio of shoulder internal rotator concentric strength was related to peak shoulder and elbow torques with an increase in the bilateral ratio of shoulder strength leading to reduced joint torques. Increases in the eccentric external rotator to concentric internal rotator strength (functional ratio) of the dominant arm and increases in dominant arm eccentric internal rotator strength were both related to increases in each joint torque. Results from the study indicate that pitch speed, passive shoulder external rotation ROM, and the isokinetic shoulder strength profile including internal rotator strength and functional strength ratio of pitchers are related to joint loading during the pitch and may be important to monitor in relation to injury risk and/or during rehabilitation. These results provide insight into the role that both shoulder ROM and rotator cuff strength play in the dynamic stabilization of the elbow and shoulder during pitching.

Shoulder Internal Rotation Contracture Formation in Surgically Managed C5, C6 Brachial Plexus Birth Injuries: Neurotmetic Lesions Fare Worse Than Avulsions.

A typical feature in infants with severe C5-C6 brachial plexus birth injury (BPBI) requiring nerve repair is the formation of shoulder internal rotation contracture (IRC). The underlying pathophysiological mechanism is unknown, and the sequelae can be difficult to treat. The severity of the IRC differs among children. C5-C6 lesions are heterogeneous at the root level. Our null hypothesis was that the type of root-level lesion (axonotmesis or neurotmesis versus avulsion) was not associated with the extent of IRC formation over time in children with upper-trunk BPBI. We performed a retrospective analysis of all patients with upper-trunk BPBI who underwent primary surgery of the C5 and/or C6 spinal nerves between 1990 and 2020 and had follow-up of at least 2 years. The primary outcome was passive shoulder external rotation (ER) in adduction at 1, 3, 5, 7, and 15 years of age. The secondary outcome was whether additional shoulder surgery was performed. The relationship between the nature of the C5-C6 lesion and IRC formation was analyzed using linear mixed models. The Kaplan-Meier method was used to estimate the cumulative risk of secondary shoulder procedures. In total, 322 patients were analyzed; mean follow-up was 7.2 ± 4.6 years. The C5-C6 root lesion type was significantly related to the passive range of ER (overall test in linear mixed model, p = 0.007). Children with avulsion of C5 and C6 (n = 21) had, on average, 18° (95% confidence interval [CI], 6.3° to 30°) less IRC formation than those with neurotmesis of C5 and C6 (n = 175) and 17° (2.9° to 31°) less than those with neurotmesis of C5 and avulsion of C6 (n = 34). IRC formation did not differ between the neurotmesis C5-C6 and neurotmesis C5-avulsion C6 groups. Secondary shoulder procedures were performed in 77 patients (10-year risk, 28% [95%CI, 23% to 34%]). Shoulder IRC formation in infants with BPBI with surgically treated C5-C6 lesions occurs to a lesser degree if the C5 root is avulsed than when C5 is neurotmetic. This finding provides insight into the possible causative pathoanatomy and may ultimately lead to strategies to mitigate IRC. Prognostic Level III . See Instructions for Authors for a complete description of levels of evidence.

Passive mobilisation of the shoulder in subacute stroke patients with persistent arm paresis: A randomised multiple treatment trial.

BackgroundPerforming a careful but effective mobilisation of the hemiplegic shoulder is essential for optimal muscle activation and to preserve the passive range of motion (PROM) needed to perform functional tasks. Studies concerning passive mobilisation of the post-stroke shoulder are scarce.ObjectivesA randomised multiple treatment trial was conducted to compare the effects of different mobilisation techniques on shoulder PROM.MethodEleven participants with upper limb paresis in the subacute phase after stroke underwent three different mobilisation techniques (3 × 4 weeks):(1) combined soft-tissue mobilisation in the scapular plane, (2) scapular mobilisation without glenohumeral movement, (3) angular glenohumeral mobilisation in the frontal plane. Depending on the randomisation, the order of the techniques changed. Differences in outcome measures (PROM shoulder, shoulder pain, spasticity of shoulder muscles and biceps, trunk impairment scale and Fugl-Meyer assessment) were calculated between the beginning and end of each intervention period.ResultsUsing combined soft-tissue mobilisation in patients in the subacute phase after stroke with persistent arm paresis resulted in an increased passive shoulder external rotation (p = 0.006). An average increase of 6.82° (± 9.20°) for shoulder external rotation was noted, whilst after the two other techniques, passive external rotation decreased (scapular mobilisation −7.27° ± 10.81°; angular mobilisation −5.45° ± 11.72°).ConclusionThese preliminary findings, suggest that combined soft-tissue mobilisation technique might improve the PROM for external shoulder rotation in subacute stroke patients with persistent arm paresis.Clinical implicationsPerforming a specific mobilisation technique might have positive effects on shoulder PROM. Research including larger sample sizes is necessary to confirm these findings and define the underlying mechanisms.

Location of brachial plexus birth injury affects functional outcomes in a rat model.

Brachial plexus birth injury (BPBI) results in shoulder and elbow paralysis with shoulder internal rotation and elbow flexion contracture as frequent sequelae. The purpose of this study was to develop a technique for measuring functional movement and examine the effect of brachial plexus injury location (preganglionic and postganglionic) on functional movement outcomes in a rat model of BPBI, which we achieved through integration of gait analysis with musculoskeletal modeling and simulation. Eight weeks following unilateral brachial plexus injury, sagittal plane shoulder and elbow angles were extracted from gait recordings of young rats (n = 18), after which rats were sacrificed for bilateral muscle architecture measurements. Musculoskeletal models reflecting animal-specific muscle architecture parameters were used to simulate gait and extract muscle fiber lengths. The preganglionic neurectomy group spent significantly less (p = 0.00116) time in stance and walked with significantly less (p < 0.05) elbow flexion and shoulder protraction in the affected limb than postganglionic neurectomy or control groups. Linear regression revealed no significant linear relationship between passive shoulder external rotation and functional shoulder protraction range of motion. Despite significant restriction in longitudinal muscle growth, normalized functional fiber excursions did not differ significantly between groups. In fact, when superimposed on a normalized force-length curve, neurectomy-impaired muscle fibers (except subscapularis) accessed regions of the curve that overlapped with the control group. Our results suggest the presence of compensatory motor control strategies during locomotion following BPBI. The clinical implications of our findings support emphasis on functional movement analysis in treatment of BPBI, as functional and passive outcomes may differ substantially.

Shoulder internal rotation contracture in brachial plexus birth injury: proximal or distal subscapularis release?

In cases of brachial plexus birth injury with internal rotation contracture of the shoulder, the subscapularis muscle may be released proximally, from the subscapular fossa, or distally, along with periarticular soft tissues arthroscopic to the glenohumeral joint. We hypothesized that the indication for each procedure would rely primarily on patients' bone remodeling potential and periarticular soft-tissue contractures, performing proximal releases in patients aged < 4 years and periarticular distal releases in older patients. The purpose of this study was to analyze the outcomes such a strategy could provide. All patients presenting with brachial plexus birth injury-related shoulder internal rotation contractures who underwent a subscapularis release were included; in addition, to restore the joint axial balance, the infraspinatus was systematically reanimated with a tendon transfer (ie, latissimus dorsi or lower trapezius) during the same operating time. Chartreview yielded preoperative and postoperative clinical and radiographic measurements, including active and passive rangeof motion of the shoulder in external rotation (ER) with the arm at the side of the body, the modified Mallet score, glenoid version, and the percentageof the humeral head arthroscopicto the middle of the glenoid process. Between July 2012 and January 2018, 28 children were operated on at our institution. In patients who underwent proximal subscapularis release(n = 13), significant improvements were observed regarding active shoulder ER, passive shoulder ER, the modified Mallet score, glenoid version, and the percentage of the humeral head arthroscopic to the middle of the glenoid process, averaging 58° ± 32° (P < .0001), 56° ± 20° (P < .0001), 9.7 ± 3.1 points (P = .0006), 15° ± 10° (P = .0034), and 24% ± 20% (P = .0113), respectively, after a mean follow-up period of 4 years. Following distal release procedures (n = 15), these improvements averaged 26° ± 29° (P = .0024), 27° ± 28°(P = .0011), 3.3 ± 4.1 points (P = .0049), 2° ± 17° (P = .4086), and 4% ± 18% (P = .215), respectively, after a mean follow-up period of 3 years. When combined with axial rebalancing of the joint, the proximal release of the subscapularis muscle appears to be sufficient to provide satisfactory functional outcomes in patients with great bone remodeling potential and supple periarticular soft tissues. In older patients, a more comprehensive release of the glenohumeral joint's arthroscopic aspect seems to provide lower but still significant clinical improvements.

Double nerve transfer for restoring external rotation of the glenohumeral joint after neonatal brachial plexus injury.

The probability of spontaneous recovery of shoulder external rotation in neonatal brachial plexus injury (NBPI) is very low after the age of 18 months. We report the outcomes of double nerve transfers to restore active external rotation of the glenohumeral joint in children with NBPI after this age. Retrospective analysis of 20 children of mean age of 23.8 months with a mean follow-up of 14.8 months. Inclusion criteria were: age > 18 months, full passive glenohumeral external rotation in abduction, and absence of severe joint deformity on MRI. The spinal accessory nerve was transferred to the infraspinatus motor branch and the long head of the triceps motor branch to the teres minor motor branch. Anterior shoulder release was associated when passive shoulder external rotation in adduction (pERADD) was <30° (n = 13, Group R vs. Group N-no release n = 7). Active shoulder elevation and external rotation in abduction (aERABD) of the glenohumeral joint were evaluated pre- and postoperatively. All children except two in Group R, recovered aERABD 4-6 months after surgery. Mean postoperative aERABD was 70 ± 32.4 and 82.9 ± 11.1° and shoulder elevation gain was 24.6 ± 22.2 and 27.1 ± 29.2° for Group R and N, respectively, without statistically significant differences. Late nerve transfers to external rotator muscles are effective in children with NBPI. This might be explained not only by muscle reinnervation, but also by the interruption of a previous co-contraction or developmental apraxia. Therapeutic IV.

SHOULDER RANGE OF MOTION CHARACTERISTICS IN DIVISION III COLLEGIATE SOFTBALL AND BASEBALL PLAYERS

Adaptive changes may occur to the throwing shoulder of overhead athletes that can influence range-of-motion (ROM). Shoulder ROM characteristics of Division III softball (SB) and baseball (BB) players are unique. To report the passive ROM characteristics of Division III SB and BB players and identify similarities and differences between these two populations. Descriptive, observational research on measurement. Participants included healthy Division III BB (n = 50) and SB (n = 24) players. Passive shoulder internal rotation (IR) and external rotation (ER) ROM were measured in the supine position with the arm in 90 ° of abduction and the scapula stabilized. Descriptive statistics and frequency distributions were used to describe ROM. Paired and independent t-tests were also used to compare throwing and non-throwing shoulder ROM for athletes of each sport and to compare the shoulder ROM of SB and BB players, respectively. The IR and ER ROM for BB players throwing shoulders (IR 54.1 ± 10.9 °; ER 94.1 ± 9.1 °) were significantly different (p < 0.001) from their non-throwing shoulders (IR 63.3 ± 11.1 °; ER 87.6 ± 9.2 °) while SB players were not (p = .06 & .08, respectively). Compared to the BB players, the throwing shoulder of SB players demonstrated statistically significantly higher IR ROM (p < .001, mean difference = 11.8 °, 95% CI: 6.4-17.2 °) as well as higher total range of motion (TRM) (p < .001, mean difference = 14.4 °, 95% CI: 8.6-20.2 °) when compared to BB players. Glenohumeral internal rotation deficit (GIRD) was significantly higher in BB players when compared to SB players (p = .042, 95% CI: .2-10.8 °). There were no significant differences in IR, ER, TRM, GIRD and ER gain between SB or BB pitchers and all other field positions (p > .05). SB players have more ROM and bilateral symmetry when compared to BB players. TRMD occurred more often than GIRD in BB players, indicating that they did not adaptively gain the same amount of ER while losing IR. The throwing shoulder ROM characteristics of both SB and BB players in this study were not influenced by the player's position (pitcher vs. field player). Level III.

Acute and Longitudinal Effects of Pitching on Passive Range of Motion in Division I Athletes

PURPOSE: To assess passive range of motion (ROM) measurements acutely over time and how this acute change alters over the course of a baseball season. METHODS: Seven healthy male NCAA Division I baseball pitchers were measured prior to the start of the season. Each pitcher was assessed for passive shoulder and elbow ROM, with measurements taken after each pitching bout during the season. Pitching bouts were allotted to early season, mid-season, or late season. In addition to ROM measurements, pitch volume, pitch type, and ball velocity were also collected for analysis. RESULTS: Following a pitching bout, passive shoulder external rotation decreased by 7% (p = 0.000) during the early season. However, passive shoulder internal rotation was significantly reduced during the early season (-37%; p = 0.001), mid-season (-30%; p = 0.000), and late season (-42%; p= 0.000). Further, total motion also decreased during the early season (-12%; p= 0.000), mid-season (-6%; p= 0.000), and late season (-9%; p= 0.000). In terms of pitch type, increasing the volume of fastballs thrown had a moderate correlation with loss of passive shoulder external rotation during the late season (r= -0.705). Increasing the volume of curveballs thrown had a moderate correlation with total motion lost during the late season (r= -0.665) as well as with passive elbow extension lost during mid-season (r= -0.760). CONCLUSIONS: Passive ROM is significantly impacted immediately after throwing. This decrease continues to be present throughout all parts of the baseball season. Moreover, a moderate correlation of fastballs and curveballs to losses in passive ROM indicates that attention to pitch type may be warranted, particularly during the middle and latter parts of the baseball season.

Low Range of Shoulders Horizontal Abduction Predisposes for Shoulder Pain in Competitive Young Swimmers.

The prevalence of shoulder pain (SP) among competitive swimmers is high, and may profoundly restrict their ability to compete. This prospective cohort study investigated the association between 3 blocks of performance factors (anthropometric characteristics, sport experience and training regimen) and the presence of SP. The aims of the present study were: (a): to determine the profile of shoulder flexibility in young swimmers, (b) to analyze whether a restricted range of movement (ROM) could be a predictor of subsequent SP in young swimmers. 24 competitive young swimmers were measured in the 2016 pre-season. Measures of passive maximal shoulder extension (SE), flexion (SF), horizontal abduction (SHAB), abduction (SAB), horizontal adduction (SHADD), external (SER) and internal (SIR) rotation ROMs were taken. SP was prospectively monitored during the subsequent season using questionnaires. The data was analyzed via a binary logistic regression and ROC curves were calculated. At the follow-up, 16 swimmers (50%) had developed unilateral SP. Only reduced SHAB ROM was associated with SP [SP group 36.6° vs. pain-free group 41.5°; p = 0.005, d = -0.96 (moderate effect sizes)]. Using the coordinates of the curves, the angle of SHAB ROM that most accurately identified individuals at risk of developing SP was determined to be 39° (sensibility 0.656 and 0.375 specificity). Swimmers with limited ROM (≤39°) have 3.6 times higher risk of developing SP than swimmers with normal ROM (>39°). This study clearly shows that low range of SHAB is a risk factor for developing SP in competitive young swimmers. In the studied data, a SHAB range of 39° was found to be the most appropriate cut-off point for prognostic screening.

A COMPARATIVE STUDY OF PASSIVE SHOULDER ROTATION RANGE OF MOTION, ISOMETRIC ROTATION STRENGTH AND SERVE SPEED BETWEEN ELITE TENNIS PLAYERS WITH AND WITHOUT HISTORY OF SHOULDER PAIN

Glenohumeral internal rotation deficit and external rotation strength have been associated with the development of shoulder pain in overhead athletes. To examine the bilateral passive shoulder rotational range of motion (ROM), the isometric rotational strength and unilateral serve speed in elite tennis players with and without shoulder pain history (PH and NPH, respectively) and compare between dominant and non-dominant limbs and between groups. Cohort study. Fifty-eight elite tennis players were distributed into the PH group (n = 20) and the NPH group (n = 38). Serve velocity, dominant and non-dominant passive shoulder external and internal rotation (ER and IR) ROM, total arc of motion (TAM: the sum of IR and ER ROM), ER and IR isometric strength, bilateral deficits and ER/IR strength ratio were measured in both groups. Questionnaires were administered in order to classify characteristics of shoulder pain. The dominant shoulder showed significantly reduced IR ROM and TAM, and increased ER ROM compared to the non-dominant shoulder in both groups. Isometric ER strength and ER/IR strength ratio were significantly lower in the dominant shoulder in the PH group when compared with the NPH group. No significant differences between groups were found for serve speed. These data show specific adaptations in the IR, TAM and ER ROM in the dominant shoulder in both groups. Isometric ER muscle weakness and ER/IR strength ratio deficit appear to be associated with history of shoulder injuries in elite tennis players. It would be advisable for clinicians to use the present information to design injury prevention programs. 2.

Effect of EMG-triggered neuromuscular electrical stimulation with bilateral arm training on hemiplegic shoulder pain and arm function after stroke: a randomized controlled trial

BackgroundHemiplegic shoulder pain is a frequent complication after stroke, leading to limited use of the affected arm. Neuromuscular electrical stimulation (NMES) and transcutaneous electrical nerve stimulation (TENS) are two widely used interventions to reduce pain, but the comparative efficacy of these two modalities remains uncertain. The purpose of this research was to compare the immediate and retained effects of EMG-triggered NMES and TENS, both in combination with bilateral arm training, on hemiplegic shoulder pain and arm function of stroke patients.MethodsA single-blind, randomized controlled trial was conducted at two medical centers. Thirty-eight patients (25 males and 13 females, 60.75 ± 10.84 years old, post stroke duration 32.68 ± 53.07 months) who had experienced a stroke more than 3 months ago at the time of recruitment and hemiplegic shoulder pain were randomized to EMG-triggered NMES or TENS. Both groups received electrical stimulation followed by bilateral arm training 3 times a week for 4 weeks. The primary outcome measures included a vertical Numerical Rating Scale supplemented with a Faces Rating Scale, and the short form of the Brief Pain Inventory. The secondary outcome measures were the upper-limb subscale of the Fugl-Meyer Assessment, and pain-free passive shoulder range of motion. All outcomes were measured pretreatment, post-treatment, and at 1-month after post-treatment. Two-way mixed repeated measures ANOVAs were used to examine treatment effects.ResultsCompared to TENS with bilateral arm training, the EMG-triggered NMES with bilateral arm training was associated with lower pain intensity during active and passive shoulder movement (P =0.007, P =0.008), lower worst pain intensity (P = 0.003), and greater pain-free passive shoulder abduction (P =0.001) and internal rotation (P =0.004) at follow-up. Both groups improved in pain at rest (P =0.02), pain interference with daily activities, the Fugl-Meyer Assessment, and pain-free passive shoulder flexion and external rotation post-treatment (P < 0.001) and maintained the improvement at follow-up (P < 0.001), except for resting pain (P =0.08).ConclusionsEMG-triggered NMES with bilateral arm training exhibited greater immediate and retained effects than TENS with bilateral arm training with respect to pain and shoulder impairment for chronic and subacute stroke patients with hemiplegic shoulder pain.Trial registrationNCT01913509.

Muscular and glenohumeral changes in the shoulder after brachial plexus birth palsy: an MRI study in a rat model

BackgroundShoulder abnormalities are the major cause of morbidity in upper brachial plexus birth palsy (BPBP). We developed a rat model of upper trunk BPBP and compared our findings to previously reported animal models and to clinical findings in humans.MethodsForty-three 5-day-old newborn rats underwent selective upper trunk neurectomy of the right brachial plexus and were studied 3 to 20 weeks after surgery. The passive shoulder external rotation was measured and the shoulder joint was assessed bilaterally by a 7.2T MRI bilaterally.ResultsWe found a marked decrease in passive shoulder external rotation, associated with a severe subscapularis muscle atrophy and contracture. None however developed the typical pattern of glenohumeral dysplasia.ConclusionsIn contradiction with previous reports, our study shows that the rat model is not adequate for preclinical studies of shoulder dysplasia. However, it might serve as a useful model for studies analyzing shoulder contracture occurring after upper BPBP.

The role of subscapularis muscle denervation in the pathogenesis of shoulder internal rotation contracture after neonatal brachial plexus palsy: A study in a rat model

We assessed the role of subscapularis muscle denervation in the development of shoulder internal rotation contracture in neonatal brachial plexus injury. Seventeen newborn rats underwent selective denervation of the subscapular muscle. The rats were evaluated at weekly intervals to measure passive shoulder external rotation. After 4 weeks, the animals were euthanized. The subscapularis thickness was measured using 7.2T MRI axial images. The subscapularis muscle was then studied grossly, and its mass was registered. The fiber area and the area of fibrosis were measured using collagen-I inmunostained muscle sections. Significant progressive decrease in passive shoulder external rotation was noted with a mean loss of 58° at four weeks. A significant decrease in thickness and mass of the subscapularis muscles in the involved shoulders was also found with a mean loss of 69%. Subscapularis muscle fiber size decreased significantly, while the area of fibrosis remained unchanged. Our study shows that subscapularis denervation, per se, could explain shoulder contracture after neonatal brachial plexus injury, though its relevance compared to other pathogenic factors needs further investigation.

Use of Botulinum Toxin Type A in the Management of Neonatal Brachial Plexus Palsy

To evaluate functional outcomes and the impact on surgical interventions after the use of botulinum neurotoxin type A (BoNT-A) for muscle imbalance, cocontractions, or contractures with neonatal brachial plexus palsy. A retrospective cohort study. A brachial plexus center in a tertiary children's hospital. Fifty-nine patients with neonatal brachial plexus palsy (75 injection procedures, 91 muscles and/or muscle groups) received BoNT-A injections (mean age at injection, 36.2 months; range, 6-123 months; 31 boys; 30 right-sided injuries, 28 left-sided injuries, 1 bilateral injury). Data collected retrospectively from medical records, from procedure notes andclinic visits before BoNT-A use, at≤6 months follow-up (BoNT-A active [BA]) andat≥7 months follow-up (BoNT-A not active [BNA]) included demographics, injection indication, side, and site(s), previous surgical history, occupational therapy and/or physical therapy plan, and outcome measurements. Outcomes assessed before and after injections included active and passive range of motion, Mallet and Toronto scores, parent comments about arm function, preinjection surgical considerations, and postinjection surgical history. Injection procedures included 51 to shoulder internal rotators, 15 triceps, 15 pronator teres, 9 biceps, and 1 flexor carpi ulnaris. Active and passive shoulder external rotation (SER) range of motion improved after shoulder internal rotator injections (P=.0003 and P= .002, respectively), as did Mallet scores with BA; the latter were sustained with BNA. Surgical intervention was averted, modified, or deferred after BoNT-A in 45% (n= 20) under surgical consideration before BoNT-A. Active elbow flexion improved in 67% (P= .005), sustained BNA (P= .004) after triceps injections; 2 of 7 patients averted surgery. Active supination improved with BA (P= .002), with gains sustained BNA (P=.016). Passive elbow extension improved after biceps injections by an average 17° (P= .004) BA, although not sustained BNA. BoNT-A is an effective adjunct to therapy and surgery in managing muscle imbalance, cocontractions, and contractures in neonatal brachial plexus palsy. Use of BoNT-A can result in averting, modifying, or deferring surgical interventions in a number of affected children.

The role of muscle imbalance in the pathogenesis of shoulder contracture after neonatal brachial plexus palsy: a study in a rat model

An internal rotation contracture of the shoulder is common after neonatal brachial plexus injuries due to subscapularis shortening and atrophy. It has been explained by 2 theories: muscle denervation and muscle imbalance between the internal and external rotators of the shoulder. The goal of this study was to test the hypothesis that muscle imbalance alone could cause subscapularis changes and shoulder contracture. We performed selective neurectomy of the suprascapular nerve in 15 newborn rats to denervate only the supraspinatus and the infraspinatus muscles, leaving the subscapularis muscle intact. After 4 weeks, passive shoulder external rotation was measured and a 7.2-T magnetic resonance imaging scan of the shoulders was used to determine changes in the infraspinatus and subscapularis muscles. The subscapularis muscle was weighed to determine the degree of mass loss. An additional group of 10 newborn rats was evaluated to determine the sectional muscle fiber size and muscle area of fibrosis by use of images from type I collagen immunostaining. There was a significant decrease in passive shoulder external rotation, with a mean loss of 66°; in the thickness of the denervated infraspinatus, with a mean loss of 40%; and in the thickness and weight of the non-denervated subscapularis, with mean losses of 28% and 25%, respectively. No differences were found in subscapularis muscle fiber size and area of fibrosis between shoulders after suprascapular nerve injury. Our study supports the theory that shoulder muscle imbalance is a cause of shoulder contracture in patients with neonatal brachial plexus palsy.