Skip Nav Destination
Close Modal
Update search
Filter
- Title
- Author
- Author Affiliations
- Full Text
- Abstract
- Keyword
- DOI
- ISBN
- ISBN-10
- ISSN
- EISSN
- Issue
- Volume
- References
- Conference Volume
- Paper No
Filter
- Title
- Author
- Author Affiliations
- Full Text
- Abstract
- Keyword
- DOI
- ISBN
- ISBN-10
- ISSN
- EISSN
- Issue
- Volume
- References
- Conference Volume
- Paper No
Filter
- Title
- Author
- Author Affiliations
- Full Text
- Abstract
- Keyword
- DOI
- ISBN
- ISBN-10
- ISSN
- EISSN
- Issue
- Volume
- References
- Conference Volume
- Paper No
Filter
- Title
- Author
- Author Affiliations
- Full Text
- Abstract
- Keyword
- DOI
- ISBN
- ISBN-10
- ISSN
- EISSN
- Issue
- Volume
- References
- Conference Volume
- Paper No
Filter
- Title
- Author
- Author Affiliations
- Full Text
- Abstract
- Keyword
- DOI
- ISBN
- ISBN-10
- ISSN
- EISSN
- Issue
- Volume
- References
- Conference Volume
- Paper No
Filter
- Title
- Author
- Author Affiliations
- Full Text
- Abstract
- Keyword
- DOI
- ISBN
- ISBN-10
- ISSN
- EISSN
- Issue
- Volume
- References
- Conference Volume
- Paper No
NARROW
Format
Journal
Article Type
Conference Series
Subject Area
Topics
Date
Availability
1-11 of 11
Carrie A. Voycheck
Close
Follow your search
Access your saved searches in your account
Would you like to receive an alert when new items match your search?
Sort by
Proceedings Papers
Proc. ASME. SBC2008, ASME 2008 Summer Bioengineering Conference, Parts A and B, 923-924, June 25–29, 2008
Paper No: SBC2008-193013
Abstract
The glenohumeral joint is the most dislocated major joint in the body with most dislocations occurring anteriorly. [1] The anterior band of the inferior glenohumeral ligament (AB-IGHL) is the primary passive restraint to dislocation and experiences the highest strains during these events. [2,3] It has been found that injuries to the capsule following dislocation include permanent deformation, which increases joint mobility and contributes to recurrent instability. [4] Many current surgical repair techniques focus on plicating redundant tissue following injury. However, these techniques are inadequate as 12–25% of patients experience pain and instability afterwards and thus may not fully address all capsular tissue pathologies resulting from dislocation. [5] Therefore, the objective of this study was to determine the effect of permanent deformation on the mechanical properties of the AB-IGHL during a tensile elongation. Improved understanding of the capsular tissue pathologies resulting from dislocation may lead to new repair techniques that better restore joint stability and improve patient outcome by placating the capsule in specific locations.
Proceedings Papers
Proc. ASME. SBC2007, ASME 2007 Summer Bioengineering Conference, 911-912, June 20–24, 2007
Paper No: SBC2007-176345
Abstract
The glenohumeral joint is the most dislocated major joint in the body and the axillary pouch of the glenohumeral capsule is the primary stabilizer at the extreme ranges of external rotation. [1] Procedures to repair the capsule following dislocation result in 12–25% of patients still experiencing pain and instability. [2] Studies performing clinical exams have found inconsistent data on differences between males and females. Increased laxity in the glenohumeral joint of females has been found as well as overall hypermobility when compared to males. [3,4] However, others have found no differences in overall joint stiffness between genders. [5] These findings suggest that a difference in the mechanical properties might exist between genders. Therefore, the objective of this study was to determine the effects of gender on the mechanical properties of the axillary pouch during tensile loading. A combined experimental and computational approach was used to evaluate the properties of the tissue. This data could potentially be utilized to improve surgical procedures and necessitate gender-specific repair techniques.
Journal Articles
Journal:
Journal of Biomechanical Engineering
Article Type: Research-Article
J Biomech Eng. March 2014, 136(3): 031003.
Paper No: BIO-13-1173
Published Online: February 13, 2014
Abstract
Previously developed experimental methods to characterize micro-structural tissue changes under planar mechanical loading may not be applicable for clinically relevant cases. Such limitation stems from the fact that soft tissues, represented by two-dimensional surfaces, generally do not undergo planar deformations in vivo. To address the problem, a method was developed to directly predict changes in the collagen fiber distribution of nonplanar tissue surfaces following 3D deformation. Assuming that the collagen fiber distribution was known in the un-deformed configuration via experimental methods, changes in the fiber distribution were predicted using 3D deformation. As this method was solely based on kinematics and did not require solving the stress balance equations, the computational efforts were much reduced. In other words, with the assumption of affine deformation, the deformed collagen fiber distribution was calculated using only the deformation gradient tensor (obtained via an in-plane convective curvilinear coordinate system) and the associated un-deformed collagen fiber distribution. The new method was then applied to the glenohumeral capsule during simulated clinical exams. To quantify deformation, positional markers were attached to the capsule and their 3D coordinates were recorded in the reference position and three clinically relevant joint positions. Our results showed that at 60deg of external rotation, the glenoid side of the posterior axillary pouch had significant changes in fiber distribution in comparison to the other sub-regions. The larger degree of collagen fiber alignment on the glenoid side suggests that this region is more prone to injury. It also compares well with previous experimental and clinical studies indicating maximum principle strains to be greater on the glenoid compared to the humeral side. An advantage of the new method is that it can also be easily applied to map experimentally measured collagen fiber distribution (obtained via methods that require flattening of tissue) to their in vivo nonplanar configuration. Thus, the new method could be applied to many other nonplanar fibrous tissues such as the ocular shell, heart valves, and blood vessels.
Proceedings Papers
Proc. ASME. SBC2011, ASME 2011 Summer Bioengineering Conference, Parts A and B, 643-644, June 22–25, 2011
Paper No: SBC2011-53507
Abstract
Glenohumeral joint stability is maintained by a combination of active and passive soft tissue structures and osteoarticular contact. Anatomical structures that contribute to each of these categories include the rotator cuff muscles, the glenohumeral capsule, and the contact between the articular surfaces of the humeral head and glenoid of the scapula, respectively. Dislocation may result in injury to one or more of these stabilizing components requiring the other structures to account for the deficit. For example, previous research has shown that a torn supraspinatus tendon results in increased bony contact forces during glenohumeral abduction. [1] Another common injury resulting from dislocation is permanent deformation of the glenohumeral capsule as the capsule is the primary static restraint to anterior translation in positions of external rotation. [2] Increased joint translations and rotations usually occur following permanent deformation [3] indicating a loss in joint stability provided by the capsule. These changes in joint kinematics following dislocation imply that differences in the contact forces between the humerus and scapula may exist as well. Irregular contact between two articular surfaces can lead to abnormal wear and an increased risk of osteoarthritis when left untreated. Therefore, the objective of this work was to assess the affect of anterior dislocation on glenohumeral joint stability by determining the in situ force in the glenohumeral capsule and the bony contact forces between the humerus and scapula during a simulated clinical exam at three joint positions in the intact and injured joint.
Proceedings Papers
Proc. ASME. SBC2011, ASME 2011 Summer Bioengineering Conference, Parts A and B, 903-904, June 22–25, 2011
Paper No: SBC2011-53492
Abstract
The glenohumeral joint is frequently dislocated causing injury to the glenohumeral capsule (axillary pouch (AP), anterior band of the inferior glenohumeral ligament (AB-IGHL), posterior band of the inferior glenohumeral ligament (PB-IGHL), posterior (Post), and anterosuperior region (AS)). [1, 2] The capsule is a passive stabilizer to the glenohumeral joint and primarily functions to resist dislocation during extreme ranges of motion. [3] When unloaded, the capsule consists of randomly oriented collagen fibers, which play a pertinent role in its function to resist loading in multiple directions. [4] The location of failure in only the axillary pouch has been shown to correspond with the highest degree of collagen fiber orientation and maximum principle strain just prior to failure. [4, 5] However, several discrepancies were found when comparing the collagen fiber alignment between the AB-IGHL, AP, and PB-IGHL. [3,6,7] Therefore, the objective was to determine the collagen fiber alignment and maximum principal strain in five regions of the capsule during uniaxial extension to failure and to determine if these parameters could predict the location of tissue failure. Since the capsule functions as a continuous sheet, we hypothesized that maximum principal strain and peak collagen fiber alignment would correspond with the location of tissue failure in all regions of the glenohumeral capsule.
Proceedings Papers
Proc. ASME. SBC2011, ASME 2011 Summer Bioengineering Conference, Parts A and B, 587-588, June 22–25, 2011
Paper No: SBC2011-53835
Abstract
Glenohumeral dislocation is a significant clinical problem and often results in injury to the anteroinferior (anterior band of the inferior glenohumeral ligament (AB-IGHL) and axillary pouch) glenohumeral capsule. [1] However, clinical exams to diagnose capsular injuries are not reliable [2] and poor patient outcome still exists following repair procedures. [3] Validated finite element models of the glenohumeral capsule may be able to improve diagnostic and repair techniques; however, improving the accuracy of these models requires adequate constitutive models to describe capsule behavior. The collagen fibers in the anteroinferior capsule are randomly oriented [4], thus the material behavior of the glenohumeral capsule has been described using isotropic models. [5,6] A structural model consisting of an isotropic matrix embedded with randomly aligned collagen fibers proved to better predict the complex capsule behavior than an isotropic phenomenological model [7] indicating that structural models may improve the accuracy of finite element models of the glenohumeral joint. Many structural models make the affine assumption (local fiber kinematics follow global tissue deformation) however an approach to account for non-affine fiber kinematics in structural models has been recently developed [8]. Evaluating the affine assumption for the capsule would aid in developing an adequate constitutive model. Therefore, the objective of this work was to assess the affine assumption of fiber kinematics in the anteroinferior glenohumeral capsule by comparing experimentally measured preferred fiber directions to the affine-predicted fiber directions.
Proceedings Papers
Proc. ASME. SBC2011, ASME 2011 Summer Bioengineering Conference, Parts A and B, 495-496, June 22–25, 2011
Paper No: SBC2011-53831
Abstract
The anteroinferior glenohumeral capsule (anterior band of the inferior glenohumeral ligament (AB-IGHL), axillary pouch) limits anterior translation, particularly in positions of external rotation, and as a result is frequently injured during anterior dislocation. [1,2] A common capsular injury is permanent tissue deformation, however, the extent and effects of this injury are difficult to evaluate as the deformation cannot be seen using diagnostic imaging. In addition, clinical exams to diagnose this injury are not reliable [3] and poor patient outcome still exists following repair procedures. [4] Previous experimental models have observed increased joint mobility following permanent tissue deformation. [5] While other models have quantified the permanent deformation using nonrecoverable strain [6], no model has correlated the amount of tissue damage to altered capsule function. Understanding the relationship between the extent of tissue damage and changes in capsule function following anterior dislocation could aid surgeons in diagnosing and treating anterior instability. Therefore, the objectives of this work were to 1) quantify the nonrecoverable strain in the anteroinferior capsule resulting from an anterior dislocation and 2) evaluate capsule function (strain distribution in anteroinferior capsule, anterior translation) during a simulated clinical exam at three joint positions, in the intact and injured joint.
Proceedings Papers
Proc. ASME. SBC2011, ASME 2011 Summer Bioengineering Conference, Parts A and B, 1287-1288, June 22–25, 2011
Paper No: SBC2011-53840
Abstract
The glenohumeral joint is the most frequently dislocated major joint in the body with about 2% of the population dislocating their shoulders between the ages of 18 and 70 [1]. About 80% of these shoulder dislocations occur in the anterior direction, and they most commonly occur in the apprehension position, which is characterized by 60° of glenohumeral abduction and 60° of external rotation [2]. The most common pathology associated with dislocation is instability due to permanent deformation [3]. Current surgical repair techniques for shoulder dislocations are inadequate with about 25% of patients still experiencing pain and instability after surgery [4]. By assessing the strain distribution, it is possible to determine the stabilizing function of the various capsular regions. In addition, surgeons could benefit from knowing the location and extent of tissue damage when placating the capsule during repair procedures. Therefore, the objective of this study was to determine the location and extent of injury to the anteroinferior capsule during anterior dislocation by quantifying the strain at dislocation and the non-recoverable strain following dislocation.
Proceedings Papers
Proc. ASME. SBC2010, ASME 2010 Summer Bioengineering Conference, Parts A and B, 463-464, June 16–19, 2010
Paper No: SBC2010-19044
Abstract
The glenohumeral joint is frequently dislocated in the anterior direction causing injury to the anteroinferior (axillary pouch, anterior band of the inferior glenohumeral ligament (AB-IGHL)) capsule. [1, 2] When unloaded, the axillary pouch consists of randomly oriented collagen fibers. These fibers play a pertinent role in its function to resist loading in multiple directions during dislocation at the extreme ranges of motion. [3] Maximum principle strain directions in the anteroinferior capsule have been shown to align with the AB-IGHL during increasing external rotation, suggesting that the collagen fibers may become more aligned with loading as well. [4] In addition, at positions of increased external rotation, the peak maximum principle strains in the capsule correspond to the location of a common capsular failure known as the Bankart lesion. [4] Further, an increase in collagen fiber alignment with load in the supraspinatus tendon has been shown in the toe region of the load-elongation curve. [5] Therefore, it was hypothesized that increases in the collagen fiber alignment and maximum principle strain would correlate with the location of tissue failure. The objective of this work was to determine the collagen fiber alignment and maximum principle strain in the axillary pouch during uniaxial extension to failure and to determine if these parameters could predict the location of tissue failure.
Proceedings Papers
Proc. ASME. SBC2010, ASME 2010 Summer Bioengineering Conference, Parts A and B, 321-322, June 16–19, 2010
Paper No: SBC2010-19267
Abstract
The glenohumeral joint suffers more dislocations than any other joint, most of which occur in the anterior direction. The anterior band of the inferior glenohumeral ligament (AB-IGHL) is the primary restraint to these dislocations and as a result experiences the highest strains during these events. [1] Injuries to the capsule following dislocation include permanent tissue deformation that increases joint mobility and contributes to recurrent instability. [2] This deformation can be quantified by measuring nonrecoverable strain. [3] Simulated injury of the capsule results in permanently elongated tissue and nonrecoverable strain. Current surgical repair techniques are subjective and may not fully address all capsular tissue pathologies resulting from dislocation. Surgeons typically repair the injured capsule by plicating the stretched-out tissue; however, these techniques are inadequate with 23% of patients needing an additional repair. [4] Quantitative data on the changes in the biomechanical properties of the capsule following dislocation may help to predict the amount of capsular tissue to plicate for restoring normal stability. Therefore, the objectives of this study were to quantify changes in stiffness and material properties of the AB-IGHL tissue sample following simulated injury (creation of nonrecoverable strain).
Proceedings Papers
Proc. ASME. SBC2010, ASME 2010 Summer Bioengineering Conference, Parts A and B, 685-686, June 16–19, 2010
Paper No: SBC2010-19258
Abstract
The shoulder is the most dislocated major joint in the body; approximately 2% of the population will dislocate their glenohumeral joint between the ages of 18 and 70 [1]. Hill-Sachs lesions, compression fractures resulting from the impaction of the posteroloateral humeral head against the solid anterior rim of the glenoid, occur in roughly 30–40% of all anterior dislocations. Humeral head defects have been linked to postoperative recurrent dislocations and overall instability of the shoulder following stabilization procedures for the capsule [2]. However, the forces and deformations required to create these lesions during shoulder dislocation should be identified to properly develop injury models and new repair techniques. Therefore, the objective of this study was to determine the forces required to create bony lesions on the humeral head and quantify the size of the resulting lesions. In order to achieve this objective, a repeatable testing protocol was developed to consistently produce Hill Sachs lesions.
