Movement control in patients with shoulder instability: a comparison between patients after open surgery and nonoperated patients

The open Latarjet procedure does not affect scapulohumeral rhythm three months postoperatively

BACKGROUND

Although it is considered a sensitive indicator of shoulder disabilities, the scapulohumeral rhythm has not been investigated after anterior glenohumeral stabilization with open Latarjet procedure. This study aimed to assess the short-term influence of glenohumeral stabilization on scapulohumeral rhythm in patients who underwent open Latarjet procedure compared to asymptomatic individuals.

METHODS

A group of male patients who underwent anterior glenohumeral stabilization by open Latarjet procedure and a healthy group were enrolled in this study. An electromagnetic device was used to record scapulothoracic and glenohumeral joint kinematics during dynamic arm elevation and depression in the scapular plane before and three months after surgery. Then, the three-dimensional dynamic scapulohumeral rhythm was computed bilaterally. SPM ANOVAs were used for statistical analysis.

FINDINGS

Twenty-two participants per group were included. The scapulohumeral rhythm of the two groups increased from 1.88 [mean] ± 0.79 [standard deviation] to 2.83 ± 1.52 during the ascending phase, while a decrease followed by a slight increase in the scapulohumeral rhythm were observed during the descending phase. The scapulohumeral rhythm did not significantly differ between the operated and non-operated sides or before and after surgery. When pooling the sides for each group, no significant differences were observed between the groups.

INTERPRETATION

The scapulohumeral rhythm in patients who underwent the Latarjet procedure is not modified three months after surgery and is similar to the scapulohumeral rhythm of asymptomatic individuals. These findings suggest that in addition to restoring glenohumeral stability, the open Latarjet procedure preserves shoulder joint coordination three months postoperatively.

Kinematic descriptors of arm reaching movement are sensitive to hemisphere-specific immediate neuromodulatory effects of transcranial direct current stimulation post stroke

Transcranial direct current stimulation (tDCS) exerts beneficial effects on motor recovery after stroke, presumably by enhancement of adaptive neural plasticity. However, patients with extensive damage may experience null or deleterious effects with the predominant application mode of anodal (excitatory) stimulation of the damaged hemisphere. In such cases, excitatory stimulation of the non-damaged hemisphere might be considered. Here we asked whether tDCS exerts a measurable effect on movement quality of the hemiparetic upper limb, following just a single treatment session. Such effect may inform on the hemisphere that should be excited. Using a single-blinded crossover experimental design, stroke patients and healthy control subjects were assessed before and after anodal, cathodal and sham tDCS, each provided during a single session of reaching training (repeated point-to-point hand movement on an electronic tablet). Group comparisons of endpoint kinematics at baseline-number of peaks in the speed profile (NoP; smoothness), hand-path deviations from the straight line (SLD; accuracy) and movement time (MT; speed)-disclosed greater NoP, larger SLD and longer MT in the stroke group. NoP and MT revealed an advantage for anodal compared to sham stimulation of the lesioned hemisphere. NoP and MT improvements under anodal stimulation of the non-lesioned hemisphere correlated positively with the severity of hemiparesis. Damage to specific cortical regions and white-matter tracts was associated with lower kinematic gains from tDCS. The study shows that simple descriptors of movement kinematics of the hemiparetic upper limb are sensitive enough to demonstrate gain from neuromodulation by tDCS, following just a single session of reaching training. Moreover, the results show that tDCS-related gain is affected by the severity of baseline motor impairment, and by lesion topography.

Risk factors for shoulder injuries in handball: systematic review

BACKGROUND

Handball is a sport with a high number of severe injuries. The shoulder is one of the most commonly injured joints, with an average prevalence of 17-41%.

OBJECTIVE

The primary aim is to identify the most significant risk factors related to shoulder injuries in handball. The secondary aim is to propose recommendations based on the available evidence concerning potential injury prevention strategies.

METHODS

Systematic searches of PubMed, MEDLINE, CINAHL, Proquest, SPORTDiscus, Web of Science, EMBASE, and Scopus were undertaken for peer reviewed articles published between 15 July 1995 and 15 July 2019. The same search strategy was repeated on 24 April 2022. Prospective cohort studies, written in English and published in a journal with a peer-review process aiming to investigate at least one modifiable or/and a non-modifiable potential risk factor for shoulder injuries, specifically in handball players, were included. Only papers published after 1995 were included. The methodological quality of the eligible studies was assessed using the modified version of the Downs and Black Checklist. The Best Evidence Synthesis (BES) approach was used for synthesizing and reporting the results.

RESULTS

1849 studies were identified, of which 8 were included. A total of 2536 (males = 1354, females = 1182) participants of which 2522 were handball athletes, were included. Four of the eight studies were rated as high methodological quality studies (> 85%) while the rest were rated as medium (50-85%). The risk factors for shoulder injuries in handball identified in the studies were strength imbalances (n = 6), glenohumeral range of motion (ROM) imbalances (n = 5), scapular dyskinesis (n = 5), incorrect dosage of training load (n = 2), previous injury (n = 1), sex (n = 2), player's position, school grade, playing level (n = 1), altered shoulder joint position sense (n = 1).

CONCLUSION

Overall, from all the risk factors evaluated, there was strong evidence that the weakness of the shoulder external rotator muscles and the female sex increase the probability of shoulder injury in handball athletes. Nevertheless, the evidence for the other risk factors was moderate due to the methodological quality and the limited number of studies.

PROTOCOL REGISTRATION

PROSPERO ID: CRD42020138233.

Proprioception: How is it affected by shoulder pain? A systematic review

INTRODUCTION

Proprioception encompasses the submodalities of joint position sense (JPS), kinesthesia, sense of force, and velocity. Owing to the vast mobility of the shoulder, it heavily relies on an intact sense of proprioception. Moreover, shoulder injuries are associated with a decreased sense of proprioception. What remains unclear is how shoulder proprioception is affected by pain and competing nociceptive senses.

PURPOSE OF THE STUDY

To summarize the literature evaluating the relationship between pain and shoulder proprioception.

METHODS

A literature review was conducted from inception until 22 October 2018, using electronic databases (PubMed, Web of Science, Scopus, EBSCO, CINAHL, and Embase). Retrieved citations were screened for eligibility, and methodological quality was assessed using the Newcastle-Ottawa Scale (NOS).

RESULTS

Eleven studies were included (n = 447 participants with shoulder pain, n = 20 with experimentally induced pain [EIP]/n = 600 painful shoulders and n = 20 [EIP]). The mean methodological quality of the studies was good (76%). Five studies investigated active JPS, four investigated passive JPS, six investigated kinesthesia, sense of force was measured in one study, and no study investigated sense of velocity. There is moderate evidence for impaired kinesthesia and low evidence for reduced sense of force among painful shoulders. Conflicting evidence is seen for the other proprioceptive submodalities.

CONCLUSION

The overall impact of pain on shoulder JPS remains unclear, while moderate evidence for an affected sense of kinesthesia is possible. There is low evidence for an impaired sense of force among painful shoulders. Standardization between studies is lacking, limiting the range of our conclusions. Further investigation is required into well-controlled and pain-induced studies to better understand the influence of pain on shoulder proprioception.

Motion quality in rotator cuff tear using an inertial measurement unit: new parameters for dynamic motion assessment

PURPOSE

This study aimed to (1) figure out the difference in motion smoothness between a nonpathologic shoulder and the other with a rotator cuff tear by measuring the angular velocity using an inertial measurement unit (IMU) sensor and (2) propose the parameters to describe the difference because there is no literature on this topic.

MATERIAL AND METHODS

We enrolled patients with rotator cuff disease diagnosed by magnetic resonance imaging. The intact shoulder of participants was compared with the shoulder with rotator cuff tear by using IMU on the basis of the parameters that establish motion smoothness: the number of peaks, the peak velocity-to-mean velocity ratio (PV/MV), and the number of sign reversals. In addition, subgroup analysis was performed with respect to tear size (small to medium vs. large to massive). In addition, correlations with the American Shoulder and Elbow Surgeons score and symptom duration (months) were evaluated.

RESULTS

Among 24 patients (15 males, 9 females), all 3 parameters for the motion quality of patients with a rotator cuff tear exhibited significant difference. The parameters showed a significant difference between the small to medium tear group and the large to massive tear group. A negative correlation was found between symptom duration and parameters of motion quality, except for PV/MV.

CONCLUSIONS

Motion quality assessment using IMU showed a marked difference in the shoulder with a rotator cuff tear compared with the intact shoulder. Hence, IMU-based parameters for dynamic motion quality could be considered as an option for assessing the function of the shoulder.

Throwing performance in water polo is related to in-water shoulder proprioception

Water polo players require a high level of upper-extremity strength, flexibility and coordination to achieve a peak level of throwing performance. Increased levels of shoulder proprioceptive acuity, strength and range of motion (ROM) have been previously associated with higher sporting performance. A coach-rating scale, used to quantify an athlete's kicking proficiency in soccer; was adapted in the current study to measure each coach's subjective expert opinion regarding athletes' throwing mechanics, velocity, and accuracy. To examine this hypothesis shoulder proprioception acuity of 18 water polo players was measured both in-water and on-land using an AMEDA apparatus and correlated with coach-rated throwing performance and clinical measures of shoulder strength and ROM. There was a moderate positive correlation between the in-water and the on-land proprioception acuity (r = 0.47, p < 0.05). The in-water score showing a strong positive correlation with coach rated throwing mechanics (r = 0.68, p < 0.05) and velocity (r = 0.75, p = 0.02), suggesting that superior proprioception acuity contributed to fast, mechanically-efficient throwing. These findings support the notion that in-water proprioceptive acuity is an important determinant of the throwing performance achieved by water polo athletes and its measurement may be a valuable adjunct to current athlete screening.

Anterior Shoulder Instability: A Systematic Review of the Quality and Quantity of the Current Literature for Surgical Treatment

Background

Anterior shoulder instability is the most common sequela of shoulder dislocation and can result in repeated dislocations or subluxation of the glenohumeral joint. Anterior shoulder instability can be treated conservatively or surgically with several procedures.

Purpose

To date, arthroscopic Bankart is the most common surgical procedure for the treatment of anterior shoulder instability. No previous studies have compared all anterior shoulder surgical procedures. In this study, the authors performed a systematic review of journal articles describing all surgical procedures for anterior shoulder instability to determine the scientific evidence and level of recommendation.

Study Design

Systematic review; Level of evidence, 4.

Method

A comprehensive literature search was conducted (July 19, 2016) with 4 reputed databases: PubMed, EMBASE, the Cochrane databases, and Web of Science. The articles found in the literature search were screened by 2 reviewers on the basis of their titles, abstracts, and full text. Data were extracted from relevant studies, and potentially relevant records were selected for full-text review. Included articles were classified according to their scientific quality (level of evidence, 1-5). The studies were then combined for each surgical procedure, and a grade of recommendation was assigned for each procedure: grade A, treatment recommendation based on level 1 evidence studies; B, based on level 2 or 3 evidence studies; C, based on level 4 or 5 evidence and could represent conflicting results; or I, insufficient evidence to recommend a treatment. As such, the grade of recommendation provides a summary score for the quality and quantity of available literature to support the surgical procedures reviewed here.

Results

The systematic literature review generated 11,281 articles. After screening, 655 articles were included. Results revealed 31 surgical procedures for shoulder instability following dislocation: 10 surgical procedures were given an A or B recommendation; 11, a C recommendation; and 10, an I recommendation.

Conclusion

This review identified many surgical procedures to treat anterior shoulder instability. Ten of these surgical procedures had an abundant amount of published articles to describe their safety and efficacy. Arthroscopic Bankart and open Bankart were the most commonly reported procedures that cite satisfactory postoperative outcomes and limited complications. Publications on the other surgical procedures were less common. Surgeons should be careful when recommending surgery, and they should choose the appropriate surgical procedure based on evidence-based literature.

Shoulder proprioception: How is it measured and is it reliable? A systematic review

STUDY DESIGN

Systematic review.

INTRODUCTION

Constituents of proprioception include our awareness of the position (joint position sense [JPS]) and motion (kinesthesia) of our limbs in space. Proprioceptive deficits are associated with musculoskeletal disorders but remain a challenge to quantify, particularly at the shoulder.

PURPOSE OF THE STUDY

To report the psychometric values of validity, reliability, and responsiveness for shoulder JPS and/or kinesthesia protocols.

METHODS

A review of 5 databases was conducted from inception to July 2016 for studies reporting a psychometric property of a shoulder proprioception protocol. The included studies were evaluated using the QualSyst checklist and COSMIN 4-point scale.

RESULTS

Twenty-one studies were included, yielding 407 participants and 553 evaluated shoulders (n). The included studies support excellent methodological scores using the QualSyst checklist (88.1 ± 9.9%) and good psychometric scores with the COSMIN for reliability (71.1%) and moderate-to-low quality score (50%) for criterion validity. Weighted average intraclass correlation coefficients (ICCs) for intrarater reliability were highest for passive JPS and kinesthesia, ICC = 0.92 ± 0.07 (n = 214) and ICC = 0.92 ± 0.04 (n = 74), respectively. The most reliable movement and tool are internal rotation at 90° of abduction, ICC = 0.88 ± 0.01 (n = 53), and the dynamometer, ICC = 0.92 ± 0.88 (n = 225). Only 2 studies quantify an aspect of validity and no responsiveness indices were reported among the included studies.

CONCLUSION

Based on the results of the included studies, the evaluation of shoulder proprioception is most reliable when using a passive protocol with an isokinetic dynamometer for internal rotation at 90° of shoulder abduction. Standardized protocols addressing the psychometric properties of shoulder proprioception measures are needed.

LEVEL OF EVIDENCE

Level 1a: systematic review.

Translational movement within the glenohumeral joint at different rotation velocities as seen by cine MRI

BACKGROUND

The glenohumeral joint is subjected to opposing forces when the direction of shoulder motion is changed, accelerating and decelerating to make the movements. The influence of motion velocity or acceleration on translation of the humeral head has not been evaluated although direction and distance of humeral head translation has been analyzed in real time in normal shoulders. We hypothesized that, in a normal shoulder, the humeral head does not deviate significantly or suddenly during active shoulder rotation regardless of motion velocity. The purpose of this study was to clarify normal intraarticular kinematics of humeral head position and translation during axial shoulder rotation with the arm by the side of the body at different rotational velocities using cine magnetic resonance imaging (MRI).

METHODS

Both shoulders of ten healthy adults (mean age group between 27.80 ± 6.05 years) were used in this study. Prior to MRI scan, dynamic glenohumeral stability was confirmed by physical examination. The glenohumeral joint was scanned during active shoulder rotation at three angular velocities (low, medium and high velocities), with the arm by the side of the body by real-time cine MRI while recording with the help of a video camera. Translation of the humeral head and rotation angles on MR imaging and video camera were measured to match shoulder rotational positions.

RESULTS

There were no statistical differences of the humeral head position and translation among three rotation velocities (p > 0.05). Translation of the humeral head was distributed from 1.44 ± 2.45 mm anteriorly to 0.65 ± 1.84 mm posteriorly at low velocity, from 0.74 ± 1.92 mm anteriorly to 0.75 ± 2.17 mm posteriorly at medium velocity, and from 2.62 ± 2.19 anteriorly to 1.17 ± 1.44 mm posteriorly at high velocity.

CONCLUSIONS

Translation of the humeral head was shown to undergo no significant change throughout the ranges of internal and external rotation, or among different rotational velocities in dynamic stability of the glenohumeral joint.

Digital data acquisition of shoulder range of motion and arm motion smoothness using Kinect v2

BACKGROUND

Range of motion (ROM) is a clinically important parameter in evaluating joint function. However, dynamic evaluation to determine the quality of the arm motion using digitized measurement is often overlooked during clinical assessment. We evaluated the accuracy of Kinect v2 (Microsoft, Redmond, WA, USA) as a digital tool for measuring shoulder ROM objectively and proposed a concept of motion smoothness reflecting the quality of arm motion.

METHODS

Ten male participants were included in a 2-stage experiment. First, shoulder ROM was measured in 4 static poses (flexion, abduction, external rotation, and internal rotation) with Kinect v2, a 3-dimensional (3D) motion analysis system, and goniometry. Second, participants performed a point-to-point arm motion as naturally as possible. Kinematic data were collected with Kinect v2 and the 3D motion analysis system and then postprocessed to acquire parameters related to motion smoothness, including peak to mean velocity ratio, acceleration to movement time ratio, and number of peaks.

RESULTS

Kinect v2 resulted in very good agreement of ROM measurement (r > 0.9) with the 3D motion analysis (95% limits of agreement < ±8°) compared with goniometry (95% limits of agreement < ±10°). Kinect v2 also showed a good correlation and agreement of measurement of motion quality parameters compared with the 3D motion analysis (peak to mean velocity ratio, acceleration to movement time ratio, and number of peaks: r = 0.769, discrepancy = ±0.1; r = 0.922, discrepancy = ±5%; and mean = 1 ± 0, respectively).

CONCLUSIONS

We show that Kinect v2 can be used as a reliable tool to measure shoulder ROM and arm motion smoothness.

Scapular dyskinesis after Latarjet procedure

BACKGROUND

Because of detachment of the pectoralis minor and variation of the vector of the conjoint tendons, we hypothesized that the Latarjet procedure may alter scapular position and motion. The purpose of this study was to evaluate scapular position and motion in patients who underwent a Latarjet or a modified iliac crest bone graft transfer (ICBGT) procedure (J-bone graft).

METHODS

Forty-six consecutive patients treated for recurrent anterior shoulder dislocation between 2010 and 2012 were retrospectively enrolled. Twenty-three were treated with a Latarjet and 23 with an ICBGT procedure. Twenty Latarjet and 20 ICBGT patients were available at a mean follow-up of 20 months (min, 12; max, 60). We recorded the Western Ontario Instability Index, the Rowe Score, and the Subjective Shoulder Value. Scapulothoracic position was studied according to the dyskinesis yes/no method. Intraobserver and interobserver reliability of the dyskinesis assessment was assessed.

RESULTS

Intraobserver and interobserver reliability of scapula dyskinesis assessment was high (Latarjet: intratester, κ = 0.84; intertester, κ = 0.75; ICBGT: intratester, κ = 0.78; intertester, κ = 0.71). Scapular dyskinesis was observed after 5 of 20 Latarjet and after 0 of 20 ICBGT procedures (P = .047). Patients with dyskinesis had lower scores (Western Ontario Instability Index, P = .043; Rowe, P = .047; Subjective Shoulder Value, P = .046), but no statistically significant difference was found between the Latarjet and ICBGT groups. Two of the 5 scapular dyskinesis patients reached the SICK (Scapular malposition, Inferior medial scapular winging, Coracoid tenderness, and scapular dysKinesis) scapula syndrome definition.

CONCLUSIONS

Scapular dyskinesis was found in 5 of 20 patients who underwent a Latarjet procedure. Dyskinesis may be related to the detachment of the pectoralis minor, and variation of the vector and the working length of the coracobrachialis and the short head of the biceps.

Pain intensity attenuates movement control of the lumbar spine in low back pain

INTRODUCTION

Pain intensity attenuates muscular activity, proprioception, and tactile acuity, with consequent changes of joint kinematics. People suffering from low back pain (LBP) frequently show movement control impairments of the lumbar spine in sagittal plane. This cross-sectional, observational study investigated if the intensity of LBP attenuates lumbar movement control. The hypothesis was that lumbar movement control becomes more limited with increased pain intensity.

METHODS

The effect of LBP intensity, measured with a numeric rating scale (NRS), on lumbar movement control was tested using three movement control tests. The lumbar range of motion (ROM), the ratio of lumbar and hip ROM as indicators of direction specific movement control, and the recurrence and determinism of repetitive lumbar movement patterns were assessed in ninety-four persons suffering from LBP of different intensity and measured with an inertial measurement unit system. Generalized linear models were fitted for each outcome.

RESULTS

Lumbar ROM (+ 0.03°, p = 0.24) and ratio of lumbar and hip ROM (0.01, p = 0.84) were unaffected by LBP intensity. Each one point increase on the NRS resulted in a decrease of recurrence and determinism of lumbar movement patterns (-3.11 to -0.06, p ⩽ 0.05).

DISCUSSION

Our results indicate changes in movement control in people suffering from LBP. Whether decreased recurrence and determinism of lumbar movement patterns are intensifiers of LBP intensity or a consequence thereof should be addressed in a future prospective study.

Upper limb kinematics after arthroscopic and open shoulder stabilization

BACKGROUND

Shoulder joint stability mediated by proprioception is often quantified by arm repositioning tests (i.e., static end-position accuracy), overlooking ongoing movement quality. This study assessed movement quality by adopting smoothness-related kinematic descriptors. We compared performance of healthy controls with that of patients in arthroscopic shoulder stabilization and open shoulder stabilization groups. We hypothesized that arm kinematics after arthroscopic intervention would more closely resemble healthy movements compared with patients after open shoulder stabilization surgery.

METHODS

Healthy controls (N = 14) were compared with patients after arthroscopic shoulder stabilization (N = 10) and open shoulder stabilization (N = 12). Right-hand dominant subjects (the affected side in patients) performed 135 unconstrained 3-dimensional pointing movements toward visual targets (seen through pinhole goggles; i.e., no arm vision). Arm kinematic data were recorded and offline analyzed to obtain hand tangential velocity profiles further used to compute the acceleration-to-movement time ratio, peak-to-mean velocity ratio, and number of velocity peaks ("symmetry," "proportion," and "fragmentation" features, respectively). Parametric and nonparametric statistics were used for comparisons (P ≤ .05).

RESULTS

Control and arthroscopic shoulder stabilization groups presented similar acceleration-to-movement time ratio and peak-to-mean velocity ratio. Both groups differed from the open shoulder stabilization group (P = .001). Distributions of velocity peaks for control and arthroscopic shoulder stabilization groups were similar, whereas open shoulder stabilization and control subjects differed significantly (P = .028).

CONCLUSIONS

Movement quality mediated by proprioception in arthroscopic shoulder stabilization patients matches that of healthy controls, whereas performance in open shoulder stabilization patients seems inferior compared with that in healthy controls, as assessed by smoothness-related measures (less symmetrical, more fragmented movements).