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Thay Q. Lee - One of the best experts on this subject based on the ideXlab platform.
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Biomechanical comparison of an intramedullary and extramedullary Free-Tissue Graft reconstruction of the acromioclavicular joint complex.
Clinics in orthopedic surgery, 2013Co-Authors: Rishi Garg, Gregory J. Adamson, Pooya Javidan, Thay Q. LeeAbstract:BACKGROUND: Several different surgical techniques have been described to address the coracoclavicular (CC) ligaments in acromioclavicular (AC) joint injuries. However, very few techniques focus on reconstructing the AC ligaments, despite its importance in providing stability. The purpose of our study was to compare the biomechanical properties of two Free-Tissue Graft techniques that reconstruct both the AC and CC ligaments in cadaveric shoulders, one with an extramedullary AC reconstruction and the other with an intramedullary AC reconstruction. We hypothesized intramedullary AC reconstruction will provide greater anteroposterior translational stability and improved load to failure characteristics than an extramedullary technique. METHODS: Six matched cadaveric shoulders underwent translational testing at 10 N and 15 N in the anteroposterior and superoinferior directions, under AC joint compression loads of 10 N, 20 N, and 30 N. After the AC and CC ligaments were transected, one of the specimens was randomly assigned the intramedullary Free-Tissue Graft reconstruction while its matched pair received the extramedullary Graft reconstruction. Both reconstructed specimens then underwent repeat translational testing, followed by load to failure testing, via superior clavicle distraction, at a rate of 50 mm/min. RESULTS: Intramedullary reconstruction provided significantly greater translational stability in the anteroposterior direction than the extramedullary technique for four of six loading conditions (p < 0.05). There were no significant differences in translational stability in the superoinferior direction for any loading condition. The intramedullary reconstructed specimens demonstrated improved load to failure characteristics with the intramedullary reconstruction having a lower deformation at yield and a higher ultimate load than the extramedullary reconstruction (p < 0.05). CONCLUSIONS: Intramedullary reconstruction of the AC joint provides greater stability in the anteroposterior direction and improved load to failure characteristics than an extramedullary technique. Reconstruction of the injured AC joint with an intramedullary Free Tissue Graft may provide greater strength and stability than other currently used techniques, allowing patients to have improved clinical outcomes.
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Intramedullary acromioclavicular ligament reconstruction strengthens isolated coracoclavicular ligament reconstruction in acromioclavicular dislocations.
The American journal of sports medicine, 2010Co-Authors: Guillem Gonzalez-lomas, Gregory J. Adamson, Pooya Javidan, Tony Lin, Orr Limpisvasti, Thay Q. LeeAbstract:BackgroundTechniques for reconstruction of the dislocated acromioclavicular (AC) joint abound. Most, however, do not address the injured AC ligaments and capsule. Evidence exists supporting the horizontal stabilizing effect of these ligaments on the AC joint. A novel AC and coracoclavicular (CC) reconstruction technique with an intramedullary Free-Tissue Graft secured by suture buttons is low-profile, technically straightforward, and reproducible.HypothesisA novel intramedullary AC reconstruction will strengthen an isolated Free-Tissue reconstruction of the CC ligaments.Study DesignControlled laboratory study.MethodsSix cadaveric matched pair shoulders were tested with a custom testing system. Anterior-posterior and superior-inferior AC joint displacements (mm) were measured with AC joint compressions of 10 N, 20 N, and 30 N, and with translational loads of 10 N and 15 N. The same measurements were made after performing either a Free-Tissue tendon alloGraft CC reconstruction, or a Free-Tissue Graft recons...
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Biomechanical Evaluation of the Acromioclavicular Capsular Ligaments and Reconstruction with an Intramedullary Free Tissue Graft
The American journal of sports medicine, 2010Co-Authors: Jason A. Freedman, Gregory J. Adamson, Christopher N.h. Bui, Thay Q. LeeAbstract:BackgroundMultiple techniques have been reported to treat chronic acromioclavicular joint injuries. However, many have failed to restore native stability, and few have addressed reconstructing the acromioclavicular ligaments.HypothesisAn intramedullary Free semitendinosus Graft reconstruction of the acromioclavicular ligaments will demonstrate joint stability comparable with that of the intact acromioclavicular joint.Study DesignControlled laboratory study.MethodsSix matched pairs of cadaveric specimens with only the acromioclavicular capsule/ligament intact were tested at 10 N and 15 N in the anteroposterior and superoinferior directions under acromioclavicular joint compression loads of 10 N, 20 N, and 30 N. One of each pair randomly underwent reconstruction of the acromioclavicular ligaments with an intramedullary Free semitendinosus Graft, and the translational testing was repeated. Both the intact and reconstructed specimens then underwent load-to-failure testing via superior clavicle distraction at ...
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Free Tissue Graft Reconstruction of the Acromioclavicular Joint: A New Technique
Techniques in Shoulder and Elbow Surgery, 2008Co-Authors: Gregory J. Adamson, Jason A. Freedman, Thay Q. LeeAbstract:Acromioclavicular (AC) joint injuries are commonly encountered in the contact athlete. Although most may be treated nonoperatively, more severe AC dislocations require surgical stabilization. Many procedures describe repair or reconstruction of the AC joint, focusing mainly on treatment of the ruptured coracoclavicular ligaments. Clinical results have been mixed, often reporting significant complications, postoperative clavicle subluxation, and patient dissatisfaction. In addition, cadaveric testing data often demonstrate inferior biomechanical properties, compared with the native AC joint. Multiple studies have concluded that the AC ligaments are important constraints to clavicle translation, and their reconstruction should be considered in the treatment of AC joint injuries. Despite these findings, there are few techniques reported that address the AC ligaments. This report describes a new procedure for the treatment of AC injuries, involving a Free Tissue intramedullary Graft reconstruction of the AC ligaments, in addition to reconstruction of the coracoclavicular ligaments. By recreating the principal ligamentous structures, stability of the AC joint may be restored.
Gregory J. Adamson - One of the best experts on this subject based on the ideXlab platform.
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Biomechanical comparison of an intramedullary and extramedullary Free-Tissue Graft reconstruction of the acromioclavicular joint complex.
Clinics in orthopedic surgery, 2013Co-Authors: Rishi Garg, Gregory J. Adamson, Pooya Javidan, Thay Q. LeeAbstract:BACKGROUND: Several different surgical techniques have been described to address the coracoclavicular (CC) ligaments in acromioclavicular (AC) joint injuries. However, very few techniques focus on reconstructing the AC ligaments, despite its importance in providing stability. The purpose of our study was to compare the biomechanical properties of two Free-Tissue Graft techniques that reconstruct both the AC and CC ligaments in cadaveric shoulders, one with an extramedullary AC reconstruction and the other with an intramedullary AC reconstruction. We hypothesized intramedullary AC reconstruction will provide greater anteroposterior translational stability and improved load to failure characteristics than an extramedullary technique. METHODS: Six matched cadaveric shoulders underwent translational testing at 10 N and 15 N in the anteroposterior and superoinferior directions, under AC joint compression loads of 10 N, 20 N, and 30 N. After the AC and CC ligaments were transected, one of the specimens was randomly assigned the intramedullary Free-Tissue Graft reconstruction while its matched pair received the extramedullary Graft reconstruction. Both reconstructed specimens then underwent repeat translational testing, followed by load to failure testing, via superior clavicle distraction, at a rate of 50 mm/min. RESULTS: Intramedullary reconstruction provided significantly greater translational stability in the anteroposterior direction than the extramedullary technique for four of six loading conditions (p < 0.05). There were no significant differences in translational stability in the superoinferior direction for any loading condition. The intramedullary reconstructed specimens demonstrated improved load to failure characteristics with the intramedullary reconstruction having a lower deformation at yield and a higher ultimate load than the extramedullary reconstruction (p < 0.05). CONCLUSIONS: Intramedullary reconstruction of the AC joint provides greater stability in the anteroposterior direction and improved load to failure characteristics than an extramedullary technique. Reconstruction of the injured AC joint with an intramedullary Free Tissue Graft may provide greater strength and stability than other currently used techniques, allowing patients to have improved clinical outcomes.
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Intramedullary acromioclavicular ligament reconstruction strengthens isolated coracoclavicular ligament reconstruction in acromioclavicular dislocations.
The American journal of sports medicine, 2010Co-Authors: Guillem Gonzalez-lomas, Gregory J. Adamson, Pooya Javidan, Tony Lin, Orr Limpisvasti, Thay Q. LeeAbstract:BackgroundTechniques for reconstruction of the dislocated acromioclavicular (AC) joint abound. Most, however, do not address the injured AC ligaments and capsule. Evidence exists supporting the horizontal stabilizing effect of these ligaments on the AC joint. A novel AC and coracoclavicular (CC) reconstruction technique with an intramedullary Free-Tissue Graft secured by suture buttons is low-profile, technically straightforward, and reproducible.HypothesisA novel intramedullary AC reconstruction will strengthen an isolated Free-Tissue reconstruction of the CC ligaments.Study DesignControlled laboratory study.MethodsSix cadaveric matched pair shoulders were tested with a custom testing system. Anterior-posterior and superior-inferior AC joint displacements (mm) were measured with AC joint compressions of 10 N, 20 N, and 30 N, and with translational loads of 10 N and 15 N. The same measurements were made after performing either a Free-Tissue tendon alloGraft CC reconstruction, or a Free-Tissue Graft recons...
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biomechanical comparison of a modified weaver dunn and a Free Tissue Graft reconstruction of the acromioclavicular joint complex
American Journal of Sports Medicine, 2010Co-Authors: Michael G Michlitsch, Allyson A Estess, Gregory J. Adamson, Marilyn Pink, James A ShankwilerAbstract:Background: Most surgical reconstructions of the separated acromioclavicular joint do not address the injured ligaments and capsule of the acromioclavicular joint.Purpose: This study was undertaken to compare the biomechanical characteristics of a modified Weaver-Dunn reconstruction and an intramedullary acromioclavicular joint reconstruction that uses a Free-Tissue Graft for reconstruction of both the coracoclavicular and acromioclavicular ligaments.Study Design: Controlled laboratory study.Methods: Each pair of 6 matched pairs of cadaveric shoulders was randomly selected for a modified Weaver-Dunn reconstruction on 1 side and the contralateral side was used for Free-Tissue Graft reconstruction of the coracoclavicular and acromioclavicular ligamentous complexes. Anterior-posterior and superior-inferior acromioclavicular joint translation (in millimeters) was measured with acromioclavicular joint compressions of 10, 20, and 30 N, and with translational loads of 10 and 15 N both before and after acromiocla...
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Biomechanical Evaluation of the Acromioclavicular Capsular Ligaments and Reconstruction with an Intramedullary Free Tissue Graft
The American journal of sports medicine, 2010Co-Authors: Jason A. Freedman, Gregory J. Adamson, Christopher N.h. Bui, Thay Q. LeeAbstract:BackgroundMultiple techniques have been reported to treat chronic acromioclavicular joint injuries. However, many have failed to restore native stability, and few have addressed reconstructing the acromioclavicular ligaments.HypothesisAn intramedullary Free semitendinosus Graft reconstruction of the acromioclavicular ligaments will demonstrate joint stability comparable with that of the intact acromioclavicular joint.Study DesignControlled laboratory study.MethodsSix matched pairs of cadaveric specimens with only the acromioclavicular capsule/ligament intact were tested at 10 N and 15 N in the anteroposterior and superoinferior directions under acromioclavicular joint compression loads of 10 N, 20 N, and 30 N. One of each pair randomly underwent reconstruction of the acromioclavicular ligaments with an intramedullary Free semitendinosus Graft, and the translational testing was repeated. Both the intact and reconstructed specimens then underwent load-to-failure testing via superior clavicle distraction at ...
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Free Tissue Graft Reconstruction of the Acromioclavicular Joint: A New Technique
Techniques in Shoulder and Elbow Surgery, 2008Co-Authors: Gregory J. Adamson, Jason A. Freedman, Thay Q. LeeAbstract:Acromioclavicular (AC) joint injuries are commonly encountered in the contact athlete. Although most may be treated nonoperatively, more severe AC dislocations require surgical stabilization. Many procedures describe repair or reconstruction of the AC joint, focusing mainly on treatment of the ruptured coracoclavicular ligaments. Clinical results have been mixed, often reporting significant complications, postoperative clavicle subluxation, and patient dissatisfaction. In addition, cadaveric testing data often demonstrate inferior biomechanical properties, compared with the native AC joint. Multiple studies have concluded that the AC ligaments are important constraints to clavicle translation, and their reconstruction should be considered in the treatment of AC joint injuries. Despite these findings, there are few techniques reported that address the AC ligaments. This report describes a new procedure for the treatment of AC injuries, involving a Free Tissue intramedullary Graft reconstruction of the AC ligaments, in addition to reconstruction of the coracoclavicular ligaments. By recreating the principal ligamentous structures, stability of the AC joint may be restored.
James A Shankwiler - One of the best experts on this subject based on the ideXlab platform.
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biomechanical comparison of a modified weaver dunn and a Free Tissue Graft reconstruction of the acromioclavicular joint complex
American Journal of Sports Medicine, 2010Co-Authors: Michael G Michlitsch, Allyson A Estess, Gregory J. Adamson, Marilyn Pink, James A ShankwilerAbstract:Background: Most surgical reconstructions of the separated acromioclavicular joint do not address the injured ligaments and capsule of the acromioclavicular joint.Purpose: This study was undertaken to compare the biomechanical characteristics of a modified Weaver-Dunn reconstruction and an intramedullary acromioclavicular joint reconstruction that uses a Free-Tissue Graft for reconstruction of both the coracoclavicular and acromioclavicular ligaments.Study Design: Controlled laboratory study.Methods: Each pair of 6 matched pairs of cadaveric shoulders was randomly selected for a modified Weaver-Dunn reconstruction on 1 side and the contralateral side was used for Free-Tissue Graft reconstruction of the coracoclavicular and acromioclavicular ligamentous complexes. Anterior-posterior and superior-inferior acromioclavicular joint translation (in millimeters) was measured with acromioclavicular joint compressions of 10, 20, and 30 N, and with translational loads of 10 and 15 N both before and after acromiocla...
Pooya Javidan - One of the best experts on this subject based on the ideXlab platform.
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Biomechanical comparison of an intramedullary and extramedullary Free-Tissue Graft reconstruction of the acromioclavicular joint complex.
Clinics in orthopedic surgery, 2013Co-Authors: Rishi Garg, Gregory J. Adamson, Pooya Javidan, Thay Q. LeeAbstract:BACKGROUND: Several different surgical techniques have been described to address the coracoclavicular (CC) ligaments in acromioclavicular (AC) joint injuries. However, very few techniques focus on reconstructing the AC ligaments, despite its importance in providing stability. The purpose of our study was to compare the biomechanical properties of two Free-Tissue Graft techniques that reconstruct both the AC and CC ligaments in cadaveric shoulders, one with an extramedullary AC reconstruction and the other with an intramedullary AC reconstruction. We hypothesized intramedullary AC reconstruction will provide greater anteroposterior translational stability and improved load to failure characteristics than an extramedullary technique. METHODS: Six matched cadaveric shoulders underwent translational testing at 10 N and 15 N in the anteroposterior and superoinferior directions, under AC joint compression loads of 10 N, 20 N, and 30 N. After the AC and CC ligaments were transected, one of the specimens was randomly assigned the intramedullary Free-Tissue Graft reconstruction while its matched pair received the extramedullary Graft reconstruction. Both reconstructed specimens then underwent repeat translational testing, followed by load to failure testing, via superior clavicle distraction, at a rate of 50 mm/min. RESULTS: Intramedullary reconstruction provided significantly greater translational stability in the anteroposterior direction than the extramedullary technique for four of six loading conditions (p < 0.05). There were no significant differences in translational stability in the superoinferior direction for any loading condition. The intramedullary reconstructed specimens demonstrated improved load to failure characteristics with the intramedullary reconstruction having a lower deformation at yield and a higher ultimate load than the extramedullary reconstruction (p < 0.05). CONCLUSIONS: Intramedullary reconstruction of the AC joint provides greater stability in the anteroposterior direction and improved load to failure characteristics than an extramedullary technique. Reconstruction of the injured AC joint with an intramedullary Free Tissue Graft may provide greater strength and stability than other currently used techniques, allowing patients to have improved clinical outcomes.
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Intramedullary acromioclavicular ligament reconstruction strengthens isolated coracoclavicular ligament reconstruction in acromioclavicular dislocations.
The American journal of sports medicine, 2010Co-Authors: Guillem Gonzalez-lomas, Gregory J. Adamson, Pooya Javidan, Tony Lin, Orr Limpisvasti, Thay Q. LeeAbstract:BackgroundTechniques for reconstruction of the dislocated acromioclavicular (AC) joint abound. Most, however, do not address the injured AC ligaments and capsule. Evidence exists supporting the horizontal stabilizing effect of these ligaments on the AC joint. A novel AC and coracoclavicular (CC) reconstruction technique with an intramedullary Free-Tissue Graft secured by suture buttons is low-profile, technically straightforward, and reproducible.HypothesisA novel intramedullary AC reconstruction will strengthen an isolated Free-Tissue reconstruction of the CC ligaments.Study DesignControlled laboratory study.MethodsSix cadaveric matched pair shoulders were tested with a custom testing system. Anterior-posterior and superior-inferior AC joint displacements (mm) were measured with AC joint compressions of 10 N, 20 N, and 30 N, and with translational loads of 10 N and 15 N. The same measurements were made after performing either a Free-Tissue tendon alloGraft CC reconstruction, or a Free-Tissue Graft recons...
Michael G Michlitsch - One of the best experts on this subject based on the ideXlab platform.
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biomechanical comparison of a modified weaver dunn and a Free Tissue Graft reconstruction of the acromioclavicular joint complex
American Journal of Sports Medicine, 2010Co-Authors: Michael G Michlitsch, Allyson A Estess, Gregory J. Adamson, Marilyn Pink, James A ShankwilerAbstract:Background: Most surgical reconstructions of the separated acromioclavicular joint do not address the injured ligaments and capsule of the acromioclavicular joint.Purpose: This study was undertaken to compare the biomechanical characteristics of a modified Weaver-Dunn reconstruction and an intramedullary acromioclavicular joint reconstruction that uses a Free-Tissue Graft for reconstruction of both the coracoclavicular and acromioclavicular ligaments.Study Design: Controlled laboratory study.Methods: Each pair of 6 matched pairs of cadaveric shoulders was randomly selected for a modified Weaver-Dunn reconstruction on 1 side and the contralateral side was used for Free-Tissue Graft reconstruction of the coracoclavicular and acromioclavicular ligamentous complexes. Anterior-posterior and superior-inferior acromioclavicular joint translation (in millimeters) was measured with acromioclavicular joint compressions of 10, 20, and 30 N, and with translational loads of 10 and 15 N both before and after acromiocla...
