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Freddie H. Fu - One of the best experts on this subject based on the ideXlab platform.
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The effect of rotator cuff tears on reaction forces at the Glenohumeral Joint.
Journal of orthopaedic research, 2002Co-Authors: I M Parsons, Freddie H. Fu, Maria Apreleva, Savio L.y. WooAbstract:The rotator cuff muscles maintain Glenohumeral stability by compressing the humeral head into the glenoid. Disruption of the rotator cuff compromises concavity compression and can directly affect the loads on the Glenohumeral Joint. The purpose of this study was to quantify the effect of rotator cuff tears on the magnitude and direction of Glenohumeral Joint reaction forces during active shoulder abduction in the scapular plane using nine cadaveric upper extremities. Motion of the full upper extremity was simulated using a dynamic shoulder testing apparatus. Glenohumeral Joint reaction forces were measured by a universal force-moment sensor. Five conditions of rotator cuff tears were tested: Intact, Incomplete Supraspinatus Tear, Complete Supraspinatus Tear, Supraspinatus/Infraspinatus Tear, and Global Tear. Reaction forces at the Glenohumeral Joint were found to steadily increase throughout abduction and peaked at maximum abduction for all conditions tested. There were no significant differences in reaction force magnitude for the intact condition (337 +/- 88 N) or those involving an isolated incomplete tear (296 +/- 83 N) or complete tear (300 +/- 85 N) of the supraspinatus tendon. Extension of tears beyond the supraspinatus tendon into the anterior and posterior aspect of the rotator cuff led to a significant decrease in the magnitude of Joint reaction force (126 +/- 31 N). Similarly, such tears resulted in a significant change in the direction of the reaction force at the Glenohumeral Joint. These results suggest that Joint reaction forces are significantly affected by the integrity of the rotator cuff, specifically, by the transverse force couple formed by the anterior and posterior aspects of the cuff. The quantitative data obtained in this study on the effect of rotator cuff tears on magnitude and direction of the reaction force at the Glenohumeral Joint helps clarify the relationship between Joint motion, Joint compression and stability.
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experimental investigation of reaction forces at the Glenohumeral Joint during active abduction
Journal of Shoulder and Elbow Surgery, 2000Co-Authors: Maria Apreleva, I M Parsons, Jon J P Warner, Freddie H. FuAbstract:Abstract Reaction forces at the Glenohumeral Joint counterbalance the mass moment of the upper extremity during shoulder motion and are directly related to the activity of muscles across the Joint. Because stability of the Glenohumeral Joint depends on compression of the humeral head into the glenoid, reaction forces constitute an important aspect of shoulder biomechanics. The objective of this study was to measure reaction forces at the Glenohumeral Joint during active scapula plane abduction. Furthermore, to clarify the relationship between the deltoid and supraspinatus muscles throughout abduction, this study investigated the effect of 4 variations of applied muscle forces on the magnitude and direction of Glenohumeral reaction forces. We used a dynamic shoulder testing apparatus equipped with a force-moment sensor to directly measure reaction forces. Joint reaction forces increased throughout abduction and peaked at approximately 90° for all testing conditions. The largest reaction forces occurred when the ratio of applied forces favored the supraspinatus tendon, whereas simulated paralysis of the supraspinatus resulted in a significant decrease in Joint compression. There were no differences in direction of the reaction force between testing conditions. The results of this study indicate that the magnitude of Glenohumeral Joint reaction forces varies according to the ratio of forces between the supraspinatus and deltoid muscles. Thus, conditions characterized by either deltoid or supraspinatus dysfunction may result in abnormal loading mechanics at the Glenohumeral Joint. Understanding the relationship between rotator cuff function and Glenohumeral reaction forces will aid in clarifying the importance of muscular activity to shoulder stability and strength as it relates to compression of the humeral head. (J Shoulder Elbow Surg 2000;9:409-17.)
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a new dynamic testing apparatus to study Glenohumeral Joint motion
Journal of Biomechanics, 1995Co-Authors: Richard E Debski, Patrick J Mcmahon, William O Thompson, Jon J P Warner, Freddie H. FuAbstract:A dynamic shoulder testing apparatus has been developed to examine unconstrained Glenohumeral Joint motion in human cadaveric full upper extremities. Six computer-controlled hydraulic cylinders are used to simulate muscle action, while the corresponding tendon excursions and six-degree of freedom Joint motion are measured. Trials showed that the testing apparatus creates highly reproducible Glenohumeral Joint motion in the scapular plane. The apparatus can be used to examine the function of the shoulder musculature and capsuloligamentous structures during normal and pathologic motion at the Glenohumeral Joint.
Eric L Sauers - One of the best experts on this subject based on the ideXlab platform.
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Glenohumeral Joint laxity and stiffness in the functional throwing position of high school baseball pitchers
Journal of Athletic Training, 2006Co-Authors: Scott D Crawford, Eric L SauersAbstract:Context: Repetitive overhead throwing has been theorized to result in chronic adaptations to the capsuloligamentous restraints of the Glenohumeral Joint. Objective: To compare Glenohumeral Joint laxity and stiffness between the throwing and nonthrowing shoulders of high school baseball pitchers. Design: Repeated measures. Setting: High school athletic training facilities. Patients or Other Participants: Twenty-two asymptomatic high school baseball pitchers (age = 16.50 ± 0.74 years, height = 178.51 ± 7.66 cm, mass = 75.43 ± 13.24 kg) from a sample of convenience. Main Outcomes Measure(s): We used computerized stress arthrometry to measure Glenohumeral Joint laxity and stiffness. Anterior Glenohumeral Joint laxity and stiffness measures were obtained with the shoulder in 90° of abduction and both neutral rotation and 90° of external rotation. Posterior laxity and stiffness measures were obtained with the shoulder in 90° of abduction and neutral rotation. Results: No clinically significant differences were found for Glenohumeral laxity or stiffness between sides. However, a statistically significant main effect for position was present for both laxity and stiffness. Anterior Glenohumeral Joint laxity in the 90° external rotation position was significantly decreased and stiffness was increased in this position compared with the anterior at neutral and posterior at neutral positions. Conclusions: Glenohumeral Joint laxity decreases and stiffness increases in the functional throwing position of 90° of abduction and 90° of external rotation. No clinically significant side-to-side differences or directional differences were found in high school baseball pitchers.
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instrumented measurement of Glenohumeral Joint laxity reliability and normative data
Knee Surgery Sports Traumatology Arthroscopy, 2001Co-Authors: Eric L Sauers, Paul A Borsa, Derald E Herling, Rick D StanleyAbstract:This study assessed shoulder laxity using an instrumented arthrometer. We compared anterior and posterior translations at various force levels to determine the reliability of our measurement technique and to provide normative data in healthy shoulders. Fifty shoulders were assessed for Glenohumeral Joint laxity in two directions (anterior and posterior) and at four force levels (67, 89, 111, and 134 N). The dependent measure was Joint displacement. Laxity values were widely, yet normally, distributed in our group of healthy shoulders. Intraclass correlation coefficients revealed excellent between-trial reliability (0.92) and fair between-session (0.73) and between-examiner (0.74) reliability. The average standard error of measurement between trials (0.56 mm), sessions (1.5 mm), and examiners (1.7 mm) demonstrated an unprecedentedly high degree of precision for quantifying Glenohumeral Joint laxity. Paired t tests revealed no significant laxity differences between sides (P>0.05), indicating bilateral symmetry. A 2 (direction) × 4 (force) analysis of variance revealed significant differences in laxity between directions (P<0.0001) and force levels (P<0.0001). Our results show that our instrumented technique for quantifying Glenohumeral Joint laxity is precise and reproducible. Posterior translation was significantly greater than anterior, and a significant increase in translation was observed between increasing levels of force.
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Instrumented measurement of Glenohumeral Joint laxity: reliability and normative data
Knee Surgery Sports Traumatology Arthroscopy, 2001Co-Authors: Eric L Sauers, Paul A Borsa, Derald E Herling, Rick D StanleyAbstract:This study assessed shoulder laxity using an instrumented arthrometer. We compared anterior and posterior translations at various force levels to determine the reliability of our measurement technique and to provide normative data in healthy shoulders. Fifty shoulders were assessed for Glenohumeral Joint laxity in two directions (anterior and posterior) and at four force levels (67, 89, 111, and 134 N). The dependent measure was Joint displacement. Laxity values were widely, yet normally, distributed in our group of healthy shoulders. Intraclass correlation coefficients revealed excellent between-trial reliability (0.92) and fair between-session (0.73) and between-examiner (0.74) reliability. The average standard error of measurement between trials (0.56 mm), sessions (1.5 mm), and examiners (1.7 mm) demonstrated an unprecedentedly high degree of precision for quantifying Glenohumeral Joint laxity. Paired t tests revealed no significant laxity differences between sides (P>0.05), indicating bilateral symmetry. A 2 (direction) × 4 (force) analysis of variance revealed significant differences in laxity between directions (P
Jon J P Warner - One of the best experts on this subject based on the ideXlab platform.
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Glenohumeral Joint cartilage contact in the healthy adult during scapular plane elevation depression with external humeral rotation
Journal of Biomechanics, 2014Co-Authors: Jon J P Warner, Daniel Frank Massimini, Guoan LiAbstract:Abstract The shoulder (Glenohumeral) Joint has the greatest range of motion of all human Joints; as a result, it is particularly vulnerable to dislocation and injury. The ability to non-invasively quantify in-vivo articular cartilage contact patterns of Joints has been and remains a difficult biomechanics problem. As a result, little is known about normal in-vivo Glenohumeral Joint contact patterns or the consequences that surgery has on altering them. In addition, the effect of quantifying Glenohumeral Joint contact patterns by means of proximity mapping, both with and without cartilage data, is unknown. Therefore, the objectives of this study are to (1) describe a technique for quantifying in-vivo Glenohumeral Joint contact patterns during dynamic shoulder motion, (2) quantify normal Glenohumeral Joint contact patterns in the young healthy adult during scapular plane elevation depression with external humeral rotation, and (3) compare Glenohumeral Joint contact patterns determined both with and without articular cartilage data. Our results show that the inclusion of articular cartilage data when quantifying in-vivo Glenohumeral Joint contact patterns has significant effects on the anterior–posterior contact centroid location, the superior–inferior contact centroid range of travel, and the total contact path length. As a result, our technique offers an advantage over Glenohumeral Joint contact pattern measurement techniques that neglect articular cartilage data. Likewise, this technique may be more sensitive than traditional 6-Degree-of-Freedom (6-DOF) Joint kinematics for the assessment of overall Glenohumeral Joint health. Lastly, for the shoulder motion tested, we found that Glenohumeral Joint contact was located on the anterior–inferior glenoid surface.
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experimental investigation of reaction forces at the Glenohumeral Joint during active abduction
Journal of Shoulder and Elbow Surgery, 2000Co-Authors: Maria Apreleva, I M Parsons, Jon J P Warner, Freddie H. FuAbstract:Abstract Reaction forces at the Glenohumeral Joint counterbalance the mass moment of the upper extremity during shoulder motion and are directly related to the activity of muscles across the Joint. Because stability of the Glenohumeral Joint depends on compression of the humeral head into the glenoid, reaction forces constitute an important aspect of shoulder biomechanics. The objective of this study was to measure reaction forces at the Glenohumeral Joint during active scapula plane abduction. Furthermore, to clarify the relationship between the deltoid and supraspinatus muscles throughout abduction, this study investigated the effect of 4 variations of applied muscle forces on the magnitude and direction of Glenohumeral reaction forces. We used a dynamic shoulder testing apparatus equipped with a force-moment sensor to directly measure reaction forces. Joint reaction forces increased throughout abduction and peaked at approximately 90° for all testing conditions. The largest reaction forces occurred when the ratio of applied forces favored the supraspinatus tendon, whereas simulated paralysis of the supraspinatus resulted in a significant decrease in Joint compression. There were no differences in direction of the reaction force between testing conditions. The results of this study indicate that the magnitude of Glenohumeral Joint reaction forces varies according to the ratio of forces between the supraspinatus and deltoid muscles. Thus, conditions characterized by either deltoid or supraspinatus dysfunction may result in abnormal loading mechanics at the Glenohumeral Joint. Understanding the relationship between rotator cuff function and Glenohumeral reaction forces will aid in clarifying the importance of muscular activity to shoulder stability and strength as it relates to compression of the humeral head. (J Shoulder Elbow Surg 2000;9:409-17.)
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a new dynamic testing apparatus to study Glenohumeral Joint motion
Journal of Biomechanics, 1995Co-Authors: Richard E Debski, Patrick J Mcmahon, William O Thompson, Jon J P Warner, Freddie H. FuAbstract:A dynamic shoulder testing apparatus has been developed to examine unconstrained Glenohumeral Joint motion in human cadaveric full upper extremities. Six computer-controlled hydraulic cylinders are used to simulate muscle action, while the corresponding tendon excursions and six-degree of freedom Joint motion are measured. Trials showed that the testing apparatus creates highly reproducible Glenohumeral Joint motion in the scapular plane. The apparatus can be used to examine the function of the shoulder musculature and capsuloligamentous structures during normal and pathologic motion at the Glenohumeral Joint.
P M Rozing - One of the best experts on this subject based on the ideXlab platform.
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the Glenohumeral Joint rotation centre in vivo
Journal of Biomechanics, 2000Co-Authors: M. Stokdijk, Jochem Nagels, P M RozingAbstract:Within the framework of the current call for standardization in upper extremity research, three methods to determine the Glenohumeral Joint rotation centre in vivo were tested. Therefore, subjects performed humeral movements, while a 3D electromagnetic tracking device registered the motion of the humerus with respect to the scapula. For the first method to estimate the Glenohumeral Joint rotation centre five scapular bony landmarks served as input to regression equations. The second method fitted a sphere through the humeral position data and the third method calculated the rotation centre determining an optimal helical axis. The experiment consisted of two parts, at first one subject was measured 10 times, subsequently one observer measured 10 subjects twice and another observer measured these subjects once. The first part of the experiment demonstrated that all methods are capable to reproduce the rotation centre within 4 mm, but the location of the centre differed significantly between methods (p<0.001). The second part, showed that inter- and intra-observer reliability was sufficiently for the sphere-fitting method and for the helical-axes method. The two observations of one observer differed significantly (p<0.008) using the regression method. The authors prefer the helical-axes method, it is a reliable and valid method which can be applied in movement registration of healthy subjects and patients with a shoulder endoprosthesis, it can be applied in hinge Joints to determine a rotation axis instead of a rotation centre which is desirable in standardized upper extremity research, and calculation time is short.
Takeo Nagura - One of the best experts on this subject based on the ideXlab platform.
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THREE-DIMENSIONAL ANTHROPOMETRIC ANALYSIS OF THE Glenohumeral Joint IN A NORMAL ASIAN POPULATION
2018Co-Authors: Noboru Matsumura, Takuji Iwamoto, Kensuke Ochi, Kazuki Sato, Takeo NaguraAbstract:IntroductionFor anatomical reconstruction in shoulder arthroplasty, it is important to understand normal Glenohumeral geometry. Unfortunately, however, the details of the Glenohumeral Joint in Asian populations have not been sufficiently evaluated. There is a racial difference in body size, and this difference probably results in a difference in Glenohumeral size.The purpose of this study was to evaluate three-dimensional geometry of the Glenohumeral Joint in the normal Asian population and to clarify its morphologic features.MethodsAnthropometric analysis of the Glenohumeral Joint was performed using computed tomography scans of 160 normal shoulders from healthy volunteers in age from 20 to 40 years. Using OsiriX MD, Geomagic Studio, and AVIZO software, the dimensions of humeral head width, humeral head diameter, glenoid height, glenoid width, and glenoid diameter were analyzed three-dimensionally (Figure 1). In diameter analyses, the humeral head was assumed to be a sphere and the glenoid was to fit a s...
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THREE-DIMENSIONAL ANTHROPOMETRIC ANALYSIS OF THE Glenohumeral Joint IN A NORMAL ASIAN POPULATION
Journal of Bone and Joint Surgery-british Volume, 2016Co-Authors: Noboru Matsumura, Takuji Iwamoto, Kensuke Ochi, Kazuki Sato, Takeo NaguraAbstract:Introduction For anatomical reconstruction in shoulder arthroplasty, it is important to understand normal Glenohumeral geometry. Unfortunately, however, the details of the Glenohumeral Joint in Asian populations have not been sufficiently evaluated. There is a racial difference in body size, and this difference probably results in a difference in Glenohumeral size. The purpose of this study was to evaluate three-dimensional geometry of the Glenohumeral Joint in the normal Asian population and to clarify its morphologic features. Methods Anthropometric analysis of the Glenohumeral Joint was performed using computed tomography scans of 160 normal shoulders from healthy volunteers in age from 20 to 40 years. Using OsiriX MD, Geomagic Studio, and AVIZO software, the dimensions of humeral head width, humeral head diameter, glenoid height, glenoid width, and glenoid diameter were analyzed three-dimensionally (Figure 1). In diameter analyses, the humeral head was assumed to be a sphere and the glenoid was to fit a sphere (Figure 2–3). Sex differences in height, humeral length, humeral head width, humeral head diameter, glenoid height, glenoid width, and glenoid diameter were compared using Mann-Whitney U tests. The correlations between sides and among the respective parameters in the Glenohumeral dimensions were evaluated with Spearman rank correlation tests. The significance level was set at 0.05 for all analyses. Results Average height and humeral length of the volunteers were 164.7 ± 9.7 cm and 29.1 ± 1.8 cm respectively. The normal Asian Glenohumeral Joint has average humeral head width of 41.4 ± 3.7 mm, humeral head diameter of 42.9 ± 3.6 mm, glenoid height of 31.5 ± 2.8 mm, glenoid width of 23.1 ± 2.4 mm, and glenoid diameter of 62.0 ± 6.8 mm. The humeral head and glenoid were significantly larger in males than in females ( p p =0.359). The average ratio of the glenoid radius to the humeral head radius was 144.9% ± 12.2%, and the ratio was significantly larger in females than in males ( p =0.026). The Glenohumeral size was well correlated between the two sides, and there were direct correlations among the heights, humeral length, humeral head size, and glenoid size ( p Conclusions The present study revealed that the values of Glenohumeral dimensions were uniform in both males and females with a strong correlation between the dominant shoulder and the nondominant shoulder. Since there are direct correlations among height, humeral length, and the size of the Glenohumeral Joint, we can also predict the Glenohumeral size of patients from their respective heights. The present results would be useful to determine the size of implants and to improve clinical outcomes of shoulder arthroplasty for Glenohumeral Joints of Asian patients. The size of the Asian Glenohumeral Joint was obviously smaller than that reported in the past literature including black and Caucasian populations. Some shoulder prostheses that are designed in Europe or America and are widely used worldwide could be oversized for small females.
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three dimensional anthropometric analysis of the Glenohumeral Joint in a normal japanese population
Journal of Shoulder and Elbow Surgery, 2016Co-Authors: Noboru Matsumura, Takuji Iwamoto, Kensuke Ochi, Kazuki Sato, Kiyohisa Ogawa, Takeo NaguraAbstract:Background An understanding of normal Glenohumeral geometry is important for anatomical reconstruction in shoulder arthroplasty. Unfortunately, the details of the Glenohumeral Joint in Asian populations have not been sufficiently evaluated. The purpose of this study was to evaluate the 3-dimensional geometry of the Glenohumeral Joint in the normal Japanese population and to clarify its morphologic features. Methods Anthropometric analysis of the Glenohumeral Joint was performed using computed tomography scans of 160 normal shoulders from healthy Japanese volunteers. The Glenohumeral dimensions and orientation were analyzed 3-dimensionally. Sex differences and correlations between sides and among the respective parameters in the Glenohumeral dimensions were evaluated. Results The normal Japanese humeral head has an average width of 41.4 mm, thickness of 13.2 mm, diameter of 42.9 mm, retroversion of 32°, and inclination of 135°. The glenoid has an average height of 31.5 mm, width of 23.1 mm, diameter of 62.0 mm, retroversion of 0°, and inferior inclination of 2°. The values of the Glenohumeral dimensions were uniform in men and women, and the humeral head and glenoid were larger in men than in women. The Glenohumeral size was well correlated between the 2 sides, and there were direct correlations among the heights, humeral length, humeral head size, and glenoid size. Conclusions The present study revealed the Glenohumeral geometry in the normal Japanese population. The present results would be useful to determine the size of implants and to improve the design of shoulder prostheses that reflect the normal anatomy of the Asian Glenohumeral Joint.
