Shoulder Joint Position Sense Research Articles

Evaluation of shoulder joint position sense in both asymptomatic and rehabilitated professional rugby players and matched controls

Objective To assess if joint position sense (JPS) in the shoulder differed between un-injured rugby players, matched control subjects and previously injured rehabilitated rugby players. Design Mixed design. Setting University biomechanics laboratory. Participants 15 asymptomatic professional rugby union players, 15 previously injured professional rugby union players, 15 asymptomatic matched non-rugby playing controls had their JPS assessed. Main outcome measures JPS was assessed using two criterion angles in the 90° shoulder abduction position (45° and 80° external rotation). Results The study found a significant difference between groups in error score ( p = 0.02). The testing angle also had a significant effect on error score ( p = 0.002), with greater error scores occurring in the mid range position. Conclusion This study showed rugby players to have better JPS than controls, indicating JPS might not be related to injury risk. Poor JPS appears to be related to injury, players having sustained an injury have decreased JPS despite surgery and/or rehabilitation and returning to sport without incident.

Effect of taping on the shoulders of Australian football players

Background: Taping of the shoulder is common in many sports, particularly Australian football, a contact sport that often involves marking (catching) the ball overhead and has a high incidence of...

Reduced scapular muscle control and impaired shoulder joint position sense in subjects with chronic shoulder stiffness

The purpose of the present study was to determine (1) if joint position sense (JPS) in subjects with shoulder stiffness (SS) differs from that in controls; (2) if, when JPS is reduced in SS, it is related to scapular muscular activities in the mid/end ranges of motion; and (3) if a person’s function is associated with his or her level of JPS. Eighteen subjects with unilateral SS and 18 controls were included. Each subject performed abduction by self-selecting an end/mid range position. The electromagnetic motion-capturing system collected kinematic data while surface electromyography collected muscle activities (upper trapezius, lower trapezius, and serratus anterior muscles). Subjects were asked to move the upper limb to the target position (end/mid range) accurately without visual guidance. Reduced JPS was observed in subjects with SS (2.7 degrees in mid range, p < 0.05). The JPS was enhanced by an increased scapula muscular activation level in the end range of motion ( R = −0.61 for SS and −0.41 for controls) and by coordination among muscles’ activation in the mid-range of motion ( R = −0.87 for SS and R = −0.53 for controls). Impaired JPS was also related to self-reported functional status ( R = −0.56) in subjects with SS. Shoulder JPS in subjects with chronic SS is impaired in comparison with controls. In the mid-range motion, the coordination of scapula muscular activation is related to shoulder JPS. Impaired JPS is also function-related in subjects with SS. These findings suggest that the coordination among scapula muscles’ activation were important to consider in the rehabilitation of patients with chronic SS.

Unconstrained shoulder joint position sense does not change with body orientation

Our knowledge of the role of muscle activation on proprioception is incomplete. Previous work has either focused on comparing active and passive motions or manipulated both muscle activation and joint angles simultaneously. We conducted an experiment at the shoulder in which subjects' trunks were tilted backwards to decouple joint angle from joint torque. Twenty three healthy subjects underwent testing in an unconstrained joint position sense task. Kinematics were measured with a magnetic tracking device. The joint position sense task consisted of subjects moving their arms to a predetermined orientation in space with the help of visual feedback from the magnetic tracking device presented to the subjects through a head-mounted display. Subjects were then asked to reproduce the presented joint position in the absence of visual feedback. The protocol was performed under two tilts: upright and trunk tilted back 45 degrees. This allowed for a comparison of joint position sense at different joint angles (at the same resistive torque) and at different resistive torques (at the same joint angles). When comparing these two tilts, we found that matching based on elevation angle demonstrated no significant difference, while matching based on torques did find differences. These results implicate elevation angle at the shoulder as playing a more important role in modulating joint position sense than joint torque.

Does a tackling task effect shoulder joint position sense in rugby players?

Objective To assess the effect of a simulated tackling task on shoulder joint position sense (JPS) in rugby players. The study also aimed to assess if differences in JPS occurred between mid range and end of range JPS, and if the tackling task had angle-specific effects on these values. Design Repeated measures. Setting University human performance laboratory. Participants Twenty-two asymptomatic professional rugby union players. Main outcome measures JPS was assessed using two criterion angles in the 90° shoulder abduction position (45° and 80° external rotation) prior to and following a simulated tackling task. Results Prior to the tackling task JPS (absolute error scores) was worse at the 45° than 80° criterion angle ( p<0.05). Following the tackling task absolute error scores were significantly increased at the 80° angle ( p<0.001), with no significant change at the 45° angle ( p>0.05), and no significant difference was present for error scores between angles ( p=0.74). Conclusions This study found JPS to be significantly reduced following a fatiguing task. But this change was only true for the end of range position, with JPS in the mid range not changing. If the mechanoreceptors are unable to accurately report shoulder position in the outer range (stretch) position due to repetitive tackling, then there is a potential for the anterior structures to become stressed before any compensatory muscle contraction can take place. These results highlight the presence of sensorimotor system deficits following repeated tackling. These deficits are proposed to contribute to overuse injuries and micro-instability of the glenohumeral joint which may be related to the increasing rate of shoulder injuries in rugby.

Shoulder joint position sense after thermal, open, and arthroscopic capsulorrhaphy for recurrent anterior instability

Identifying the optimal surgical treatment for recurrent, anterior glenohumeral instability remains a challenge. Our purpose was to compare shoulder joint position sense among open, arthroscopic, and thermal capsulorrhaphy patients after repair of recurrent anterior instability and to compare these patients to healthy, control subjects. Sixty-seven adults (45 post-surgical patients, 22 controls) volunteered to participate in the study. We evaluated both the surgically repaired and contralateral shoulders of 45 capsulorrhaphy patients (28 men, 17 women) and compared their results with the normal bilateral shoulders of 22 age-matched controls (11 men, 11 women). Accuracy of joint position sense was quantified via passive reproduction of target positions set at 60% and 90% of each subject's maximum passive external rotation (ER(max)). We observed no significant differences in joint position sense between the repaired shoulders and the contralateral normal shoulders of all groups of capsulorrhaphy patients. Open and thermal capsulorrhaphy patients demonstrated significantly better (P </= .05) repaired-limb joint position sense (5.4 degrees +/- 3.3 degrees and 5.6 degrees +/- 3.3 degrees , respectively) than arthroscopic patients (9.2 degrees +/- 3.7 degrees ) and control subjects (8.1 degrees +/- 4.0 degrees ). These results indicate that joint position sense was similar in the repaired shoulders and uninjured shoulders of each group of capsulorrhaphy patients. The mechanism responsible for heightened position sense in open and thermal capsulorrhaphy patients is unknown, but may result from capsular retensioning and muscular scarring. The long-term implications of this outcome deserve further attention.

Recovery of Joint Position Sense in the Shoulder after Muscle Fatigue

Context:Fatigue of the shoulder rotator muscles may negatively affect joint position sense (JPS) and ultimately lead to injury.Objective:Recovery of shoulder JPS after muscle fatigue.Design:A repeated-measures study.Setting:Musculoskeletal research laboratory.Patients:Thirteen subjects participated in joint position error tests and isokinetic concentric strength assessment in shoulder rotation, before and after rotator muscle fatigue.Interventions:Local muscle fatigue was induced using isokinetic concentric contractions of the shoulder rotator muscles.Main Outcome Measurements:Shoulder rotator strength and JPS error signals were measured before fatigue, immediately after fatigue, and every ten minutes thereafter for one hour.Results:Before shoulder rotation muscle fatigue, the accuracy of shoulder JPS was 2.79 ± 1.67 degrees. After muscle fatigue, the accuracy decreased to 6.39 ± 2.90 degrees. Shoulder JPS was influenced up to 40 minutes after muscle fatigue, but shoulder strength was only affected for 10 minutes after muscle fatigue.Conclusions:Proprioceptive recovery was slower than strength following fatigue of the shoulder rotators.

Shoulder joint position sense improves with elevation angle in a novel, unconstrained task

Proprioception, encompassing the submodalities of kinesthesia and joint position sense, is important in the maintenance of joint stability, especially in the shoulder. The purpose of this study was to examine the effects of plane and elevation angle on unconstrained shoulder joint position sense. Twenty-two subjects (12 male, 10 female) without a history of shoulder pathology were recruited from a university campus. Subjects attempted to replicate, with respect to plane and elevation angles, various target positions. Target positions consisted of five plane angles at 90 degrees of arm elevation and five arm elevation angles in the scapular plane. All target positions were tested twice to assess the reliability of the measurement. Intraclass correlation coefficients were generally low across target positions, possibly owing to the novelty and demanding nature of the task. No differences in repositioning errors were observed between plane angles (p = 0.255). Repositioning errors decreased linearly as the elevation angle increased from 30 degrees to 90 degrees (p = 0.007) and increased again from 90 degrees to 110 degrees of elevation (p = 0.029). Our results suggest that unconstrained joint position sense may be enhanced with increased muscular activation levels. Further, afferent feedback from musculotendinous mechanoreceptors may dominate over that from capsuloligamentous sources in unconstrained movements.

Cryotherapy does not impair shoulder joint position sense

Dover G, Powers ME. Cryotherapy does not impair shoulder joint position sense. Arch Phys Med Rehabil 2004;85:1241–6. Objective To determine the effects of a cryotherapy treatment on shoulder proprioception. Design Crossover design with repeated measures. Setting University athletic training and sports medicine research laboratory. Participants Thirty healthy subjects (15 women, 15 men). Intervention A 30-minute cryotherapy treatment. Main outcome measures Joint position sense was measured in the dominant shoulder by using an inclinometer before and after receiving 30 minutes of either no ice or a 1-kg ice bag application. Skin temperature was measured below the tip of the acromion process and recorded every 5 minutes for the entire 30 minutes and immediately after testing. Three different types of error scores were calculated for data analyses and used to determine proprioception. Results Separate analyses of absolute, constant, and variable error failed to identify changes in shoulder joint proprioception as a function of the cryotherapy application. Conclusions Application of an ice bag to the shoulder does not impair joint position sense. The control of proprioception at the shoulder may be more complex than at other joints in the body. Clinical implications may involve modifying rehabilitation considerations when managing shoulder injuries.

The Efficacy of Modern Technology to Improve Healthy and Injured Shoulder Joint Position Sense

Assessment and enhancement of joint position sense is an inexact science at best. Anew method of evaluating and improving this sense using motion-tracking technology that incorporates computer visualization graphics was examined. Injured and healthy subjects were evaluated for their abilities to determine shoulder joint position, after abduction, in two tasks. The first was active reproduction of a passively placed angle. The second was visual reproduction of such an angle. A training protocol was added to determine the effectiveness of proprioceptive training in conjunction with 3-D visualization techniques. The primary findings were (a) a significant difference (p = .05) in the level of joint position sense in injured vs. healthy subjects; (b) significantly less accurate reproduction of larger shoulder abduction vs. the smaller movement in the active reproduction task; (c) significantly greater ability to accurately reproduce angles actively vs. visually; and (d) that proprioception training using 3-D visualization techniques significantly increased active and visual reproductions of passively placed angles.