Three-dimensional motion of the scapula and shoulder during activities of daily living

Assessing Smoothness of Arm Movements With Jerk: A Comparison of Laterality, Contraction Mode and Plane of Elevation. A Pilot Study

Measuring the quality of movement is a need and a challenge for clinicians. Jerk, defined as the quantity of acceleration variation, is a kinematic parameter used to assess the smoothness of movement. We aimed to assess and compare jerk metrics in asymptomatic participants for 3 important movement characteristics that are considered by clinicians during shoulder examination: dominant and non-dominant side, concentric and eccentric contraction mode, and arm elevation plane. In this pilot study, we measured jerk metrics by using Xsens^® inertial measurement units strapped to the wrists for 11 different active arm movements (ascending and lowering phases): 3 bilateral maximal arm elevations in sagittal, scapular and frontal plane; 2 unilateral functional movements (hair combing and low back washing); and 2 unilateral maximal arm elevations in sagittal and scapular plane, performed with both arms alternately, right arm first. Each arm movement was repeated 3 times successively and the whole procedure was performed 3 times on different days. The recorded time series was segmented with semi-supervised algorithms. Comparisons involved the Wilcoxon signed rank test (p < 0.05) with Bonferroni correction. We included 30 right-handed asymptomatic individuals [17 men, mean (SD) age 31.9 (11.4) years]. Right jerk was significantly less than left jerk for bilateral arm elevations in all planes (all p < 0.05) and for functional movement (p < 0.05). Jerk was significantly reduced during the concentric (ascending) phase than eccentric (lowering) phase for bilateral and unilateral right and left arm elevations in all planes (all p < 0.05). Jerk during bilateral arm elevation was significantly reduced in the sagittal and scapular planes versus the frontal plane (both p < 0.01) and in the sagittal versus scapular plane (p < 0.05). Jerk during unilateral left arm elevation was significantly reduced in the sagittal versus scapular plane (p < 0.05). Jerk metrics did not differ between sagittal and scapular unilateral right arm elevation. Using inertial measurement units, jerk metrics can well describe differences between the dominant and non-dominant arm, concentric and eccentric modes and planes in arm elevation. Jerk metrics were reduced during arm movements performed with the dominant right arm during the concentric phase and in the sagittal plane. Using IMUs, jerk metrics are a promising method to assess the quality of basic shoulder movement.

The effect of unsupported arm elevations on regional chest wall volumes and thoracoabdominal asynchrony in patients with chronic obstructive pulmonary disease

Objective: To compare the effect of unsupported arm elevation (UAE) in different planes on chest wall volumes, thoracoabdominal asynchrony (TAA), ventilatory demands, dyspnea, and arm fatigue in patients with chronic obstructive pulmonary disease (COPD) and healthy subjects. Methods: Twenty-one patients with COPD and healthy-matched subjects performed UAE in shoulder flexion, scaption, abduction, and resting. Pulmonary total and regional chest wall volumes (V_RCp), abdominal rib cage volume, abdominal volume, TAA, and ventilatory demands during arm positions were measured using optoelectronic plethysmography. Results: In both groups, V_RCp and TAA were significantly affected during UAEs compared with the resting position. The healthy subjects had significantly decreased V_RCp (L) (p < 0.05) during scaption (0.14 ± 0.07) and abduction (0.15 ± 0.06) than during flexion (0.18 ± 0.07) and no significantly different TAA between UAEs. The COPD group had no significantly different V_RCp between UAEs, had significantly increased TAA (p < 0.05) during scaption (31.1°±9.5°) and abduction (32.3°±9.9°) than during flexion (29.7°±9.1°); and had significantly worse V_RCp (p = 0.007), TAA (p = 0.0001), ventilatory demands (p < 0.05), dyspnea ((p = 0.03), and arm fatigue (p = 0.002). Conclusions: In patients with COPD, UAE in different planes similarly restricted the upper chest wall volume. Shoulder scaption and abduction significantly impaired TAA, ventilation, dyspnea, and arm fatigue compared with flexion. These results may help to select the appropriate UAE during physical activities.

Functional range of motion in the upper extremity and trunk joints: Nine functional everyday tasks with inertial sensors

BACKGROUND

Functional range of motion is defined as the required range of motions for individuals to maintain maximal independence, along with optimal conditions for activities of daily living. Intervention plans for rehabilitation are directed towards the acquisition of anatomical range of motion. However, this isn't always possible based on person's etiology, prognosis, or severity of disease.

RESEARCH QUESTION

The aim of this study is to determine functional range of motion during different unilateral, bilateral symmetrical and bimanual asymmetrical tasks of activities of daily living.

METHODS

Participants completed nine basic activities of daily living (hand to head, hanging jacket, eating, wallet placement to back pocket, washing hands and face, removing belt, water pouring, brushing teeth) linked according to International Classification of Functioning, Disability and Health, while joint kinematics of the trunk and upper extremity were recorded with inertial measurement units. Peak values of mean joint angles were determined for each activities of daily living. MVN BIOMECH Awinda MTW2-3A7G6 sensors (Xsens Technologies B.V. Enschede, Netherlands) were used for 3D kinematic analysis of activities.

RESULTS

Forty-six healthy subjects (right-dominant) were included in this study. Range of motion requirements of all activities were defined 37.85° extension, 91.18° flexion, 1.25° adduction, 39.45° abduction, 63.6° internal rotation, 21.8° external rotation in the dominant shoulder, 124.17° flexion in the dominant elbow, 40.29° extension, 23.66° flexion, 18.31° supination, 12.56° pronation, 18.27 ulnar deviation and, 18.36° radial deviation in the dominant wrist. Maximum trunk range of motions were found to be 29.75° flexion in C7-T1, 10.74° flexion in T12-L1, and 24.16° flexion in L5-S1.

SIGNIFICANCE

It is thought that the results of this research will contribute to the determination of normative data needed for surgical interventions, technological rehabilitation devices and task-spesific rehabilitation programs which based patient's motor skill level.

Simulated activities of daily living do not replicate functional upper limb movement or reduce movement variability

Kinematic assessments of the upper limb during activities of daily living (ADLs) are used as an objective measure of upper limb function. The implementation of ADLs varies between studies; whilst some make use of props and define a functional target, others use simplified tasks to simulate the movements in ADLs. Simulated tasks have been used as an attempt to reduce the large movement variability associated with the upper limb. However, it is not known whether simulated tasks replicate the movements required to complete ADLs or reduce movement variability. The aim of this study is to evaluate the use of simulated tasks in upper limb assessments in comparison to functional movements. Therefore answering the following questions: Do simulated tasks replicate the movements required of the upper limb to perform functional activities? Do simulated tasks reduce intra- and inter-subject movement variability? Fourteen participants were asked to perform five functional tasks (eat, wash, retrieve from shelf, comb and perineal care) using two approaches: a functional and a simulated approach. Joint rotations were measured using an optoelectronic system. Differences in movement and movement variability between functional and simulated tasks were evaluated for the thorax, shoulder, elbow/forearm and wrist rotations. Simulated tasks did not accurately replicate the movements required for ADLs and there were minimal differences in movement variability between the two approaches. The study recommends the use of functional tasks with props for future assessments of the upper limb.

Range of Motion Requirements for Upper-Limb Activities of Daily Living

OBJECTIVE

We quantified the range of motion (ROM) required for eight upper-extremity activities of daily living (ADLs) in healthy participants.

METHOD

Fifteen right-handed participants completed several bimanual and unilateral basic ADLs while joint kinematics were monitored using a motion capture system. Peak motions of the pelvis, trunk, shoulder, elbow, and wrist were quantified for each task.

RESULTS

To complete all activities tested, participants needed a minimum ROM of -65°/0°/105° for humeral plane angle (horizontal abduction-adduction), 0°-108° for humeral elevation, -55°/0°/79° for humeral rotation, 0°-121° for elbow flexion, -53°/0°/13° for forearm rotation, -40°/0°/38° for wrist flexion-extension, and -28°/0°/38° for wrist ulnar-radial deviation. Peak trunk ROM was 23° lean, 32° axial rotation, and 59° flexion-extension.

CONCLUSION

Full upper-limb kinematics were calculated for several ADLs. This methodology can be used in future studies as a basis for developing normative databases of upper-extremity motions and evaluating pathology in populations.

Range of Motion Requirements for Upper-Limb Activities of Daily Living

OBJECTIVE

We quantified the range of motion (ROM) required for eight upper-extremity activities of daily living (ADLs) in healthy participants.

METHOD

Fifteen right-handed participants completed several bimanual and unilateral basic ADLs while joint kinematics were monitored using a motion capture system. Peak motions of the pelvis, trunk, shoulder, elbow, and wrist were quantified for each task.

RESULTS

To complete all activities tested, participants needed a minimum ROM of -65°/0°/105° for humeral plane angle (horizontal abduction-adduction), 0°-108° for humeral elevation, -55°/0°/79° for humeral rotation, 0°-121° for elbow flexion, -53°/0°/13° for forearm rotation, -40°/0°/38° for wrist flexion-extension, and -28°/0°/38° for wrist ulnar-radial deviation. Peak trunk ROM was 23° lean, 32° axial rotation, and 59° flexion-extension.

CONCLUSION

Full upper-limb kinematics were calculated for several ADLs. This methodology can be used in future studies as a basis for developing normative databases of upper-extremity motions and evaluating pathology in populations.

Dynamic comparison of segmentary scapulohumeral rhythm between athletes with and without impingement syndrome

Background:

Patients who have shoulder pain usually have compensatory or contributory deviation of shoulder motion during arm elevation. In the traditional scapulohumeral rhythm, the share of the acromioclavicular (AC) and the sternoclavicular (SC) joint movements and also the role of AC internal rotation angle are unknown.

Objectives:

The main purpose of this study was to measure and compare the segmentary scapulohumeral rhythm (SSHR) during scapular arm elevation at a steady rotational speed in athletes with and without impingement syndrome.

Patients and Methods:

Using a speedometer, the maximum speed of arm elevation was measured in 21 men in each of the involved and uninvolved groups. Using fluoroscopy on the dominant side, SSHR during scapular arm elevation at a rotational speed equal to 1/30 of maximum speed was compared between the two groups. The ratio of glenohumeral (GH) elevation angle to AC rotation angle in the scapular plane was considered as SSHR.

Results:

The maximum speed of arm elevation between the two groups was significantly different (P < 0.001). The rhythm of the involved group significantly exceeded the rhythm of the uninvolved group in a part of the first quarter range of the arm elevation. SSHR during arm elevation in the uninvolved group did not change significantly (P = 0.845); however, it decreased significantly in the involved group (P = 0.024).

Conclusions:

Speed differences between the two groups were probably due to the pain in some ranges of arm elevation. SSHR in the involved group probably changed in order to compensate downward rotation of the scapula in the resting position. Study of the AC upward rotation range can be misleading; therefore, the study of scapulohumeral rhythm is recommended.

A new description of scapulothoracic motion during arm movements in healthy subjects

The participation of scapula motion in arm movement is clinically well known and recent three dimensional (3D) analyses using kinematic techniques have confirmed its importance. Scapular motion relative to the thorax has a theoretical maximum of 6 degrees of freedom (DoF), resulting from rotations at both clavicular joints (3 rotational DoF each). However, most recent kinematic studies have only analysed the 3D rotations of the scapula relative to the thorax. In the present study, the 3D translations of the barycentre of the scapula were considered in order to complete the description of movement at the shoulder complex. Eight healthy subjects performed arm elevation in the sagittal and frontal planes, simulated activities of daily living (hair combing and back washing) and maximum voluntary scapula movement (forward and backward rolling). Measurements were recorded using a 6 DoF electromagnetic device and the acromial method of analysis was used. The results showed that 3D scapular rotations and translation of its barycentre were functionally consistent for all tasks. A principal component analysis (PCA) yielded three factors, explaining 97.6% of the variance. The first two factors (protraction and shrug, according to clinical descriptions) combined rotations and translations, consistent with the hypothesis that the scapula rolls over the curved thoracic surface. The third factor related to lateral-medial rotation, thus representing rotation in the plane tangential to the thorax. The PCA suggested that scapular motion can be described using these 3 DoF. This should be studied in a larger group of individuals, including patients with pathological conditions.

The radiographic quantification of scapular malalignment after malunion of displaced clavicular shaft fractures

BACKGROUND

Malunion after displaced fractures of the clavicle can result in varying degrees of scapular malalignment and potentially scapular winging. The purpose of our study was to quantify the scapular malalignment in patients with midshaft clavicle malunions showing scapular winging.

METHODS

Eighteen patients with symptomatic midshaft clavicle malunions showing scapular winging were identified and underwent standardized computed tomography scanning of the thorax. Specific bony landmarks on the clavicle and scapula were digitized, allowing generation of 3-dimensional points. These points were acquired bilaterally so that relative translations comparing the malunited side with the contralateral side could be obtained. Statistical analysis using a paired t test was performed.

RESULTS

The mean time from fracture to examination was 42.9 months. There were 15 men and 3 women with a mean age of 41.6 years. The mean clavicular shortening was 21.1 mm (P = .0000004). The acromion of the affected scapula on average translated 24.3 mm. The components of this translation were medial, 11.9 mm (P = .00008); inferior, 20.7 mm (P = .0009); and anterior, 4.6 mm (P = .02). Posterior bony landmarks on the scapula including the superior and inferior angles of the scapula translated a total of 9.9 mm and 5.9 mm, respectively.

CONCLUSION

This is the first study to document the degree of scapular malalignment in patients with symptomatic clavicle malunions showing scapular winging. The acromion closely follows the distal clavicular fragment and translates medially, inferiorly, and anteriorly. The translations of the superior and inferior angles of the scapula are quite variable in magnitude and direction, and on average, these angles translate substantially less than the acromion.

Kinematic analysis of dynamic shoulder motion in patients with reverse total shoulder arthroplasty

BACKGROUND

Reverse total shoulder arthroplasty (rTSA) has been used to treat patients with irreparable rotator cuff dysfunction. Despite the proven clinical efficacy, there is minimal information regarding the underlying changes to the shoulder kinematics associated with this construct. Therefore, we sought to examine the kinematics of dynamic shoulder motion in patients with well-functioning rTSA.

METHODS

We tested 12 healthy subjects and 17 patients with rTSA. All rTSA patients were able to elevate their arms to at least 90° and received the implant as the primary arthroplasty at least 6 months before testing. On average, the rTSA patients elevated their arms to 112° ± 12° (mean ± SD) and reported an American Shoulder and Elbow Surgeons outcome score of 90.6 ± 6.3. A 3-dimensional electromagnetic motion capture device was used to detect the dynamic motion of the trunk, scapula, and humerus during bilateral active shoulder elevation along the sagittal, scapular, and coronal planes.

RESULTS

In both healthy and rTSA shoulders, the majority of the humeral-thoracic motion was provided by the glenohumeral motion. Therefore, the ratio of glenohumeral to scapulothoracic (ST) motion was always greater than 1.62 during elevation along the scapular plane. In comparison to healthy subjects, however, the contribution of ST motion to overall shoulder motion was significantly increased in the rTSA shoulders. This increased contribution was noted in all planes of shoulder elevation and was maintained when weights were attached to the arm.

CONCLUSION

Kinematics of the rTSA shoulders are significantly altered, and more ST motion is used to achieve shoulder elevation.

A 10-DEGREE OF FREEDOM EXOSKELETON REHABILITATION ROBOT WITH ERGONOMIC SHOULDER ACTUATION MECHANISM

Due to the advantages of more intensiveness, long duration, repeatability, and task-orientation, robot-assistant training has become a promising technology in stroke rehabilitation. Regarding the upper extremity, the natural coordination called shoulder rhythm is the most challenge to the design of ergonomic shoulder exoskeleton. Based on kinematic analysis of movement of shoulder complex, a 10-degree-of-freedom (DoF) exoskeleton rehabilitation robot with six-DoF shoulder actuation mechanism driven by pneumatic muscle through Bowden cable transmitting force is proposed. The kinematic relationship between shoulder girdle motion and the humerus flexion/retroflexion and abduction/adduction was described. The compact mechanisms for cable tension and cable disconnect/connect respectively were proposed to realize the cable automatic tension and drive-unit/manipulating-unit detachment. In order to verify the manipulability of the proposed robot during assisting patient with performing activities of daily living (ADLs), the performance criteria, i.e., normalized dexterity measure and manipulability ellipsoid, are used to evaluate and compare with human upper extremity. The evaluated results confirm the ergonomic design of shoulder mechanism of the rehabilitation robot that can provide approximate dexterity of human upper extremity in ADLs.

Quantifying scapula orientation and its influence on maximal hand force capability and shoulder muscle activity

BACKGROUND

Non-neutral scapular orientations are often implicated as potential causes of shoulder pathologies. However, their specific influence on shoulder functional capabilities is largely unknown. This study objectively measured scapular orientation and quantified its influence on shoulder muscle activity levels and hand force capabilities during vertical and horizontal manual exertions.

METHODS

Ten healthy male university students performed 24 exertions in combinations of scapular orientation (protracted, neutral and retracted), exertion direction (up, down, medial, lateral) and intensity (maximal or 40N). Scapular orientation was quantified using an acromion marker cluster method. An orientation by intensity repeated measures ANOVA identified differences in quantified scapular orientation. A two-way multivariate ANOVA identified the influence of scapular orientation and hand force direction on muscle activity and hand force capability.

FINDINGS

Participants assumed consistent retracted, neutral, and protracted scapular orientations during exertions, and these three orientations were different from each other (F(2,99)=158.57; P-value: 0.0001). Scapular orientation and exertion direction influenced muscle recruitment almost universally (P-value: 0.05). Scapular orientation did not influence hand force capability (F(2,99)=1.34; P-value: 0.05), but a hand force direction effect on force existed (F(3,99)=144.19; P-value: 0.0001).

INTERPRETATION

These findings support recommendations of health practitioners who advocate neutral scapular orientations to reduce injury risk, as a neutral orientation achieved a balanced overall muscle use pattern between retraction and protraction. Also, lowered muscle activity and higher maximal forces suggest that downward exertion forces may be preferable when possible.

The snapping scapula: diagnosis and treatment

As a largely under-recognized problem, snapping scapula stems from the disruption of normal mechanics in scapulothoracic articulation. It is especially common in the young, active patient population, and symptoms are frequently seen with overhead and throwing motions. Understanding the anatomy of the scapula and surrounding neurovascular structures is crucial in making a differential diagnosis and providing both nonoperative and surgical treatments. Common causes of snapping scapula include bursitis, muscle abnormality, and bony or soft-tissue abnormalities. Anatomic variations, such as excessive forward curvature of the superomedial border of the scapula, may also be a cause for snapping. Benign tumor conditions of the scapula can also predispose one to snapping scapula syndrome and should be thoroughly investigated during the course of treatment. Patients with snapping scapula syndrome typically present with a history of pain with overhead activities. Snapping scapula is associated with audible and palpable crepitus near the superomedial border of the scapula. Various imaging studies may be used to rule out soft-tissue and bony masses, which may cause impingement at the scapulothoracic articulation. In most cases nonoperative treatment is curative and includes physical therapy for scapular muscle strengthening and nonsteroidal anti-inflammatory medications. Corticosteroid injections may also be used for therapeutic and diagnostic purposes. In most cases overuse injuries and repetitive strains respond well to nonoperative treatments. When nonoperative measures fail, surgery is a proven modality, especially if a soft-tissue or bony mass is implicated. Both open and arthroscopic techniques have been described with predictable results.