The Experts below are selected from a list of 1155 Experts worldwide ranked by ideXlab platform
Min Zhao - One of the best experts on this subject based on the ideXlab platform.
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biomechanical comparison of anterior Oblique Ligament versus dorsal radial Ligament reconstruction of the trapeziometacarpal joint
Chinese Journal of Hand Surgery, 2017Co-Authors: Jingda Liu, Liang Zhao, Min ZhaoAbstract:Objective To compare the axial shortening resistance of anterior Oblique Ligament and dorsal radial Ligament reconstruction of trapeziometacarpal joint after trapezium excision for the patients with osteoarthritis of trapeziometacarpal joint, and to determine which method was more stable. Methods Twenty cases of male adult fresh cadaver hand specimens were dissected. After the trapezium excision, ten cases of anterior Oblique Ligament and ten cases of dorsal radial Ligament were reconstructed using half bundle of flexor carpi radialis tendon. Biomechanical testing was performed to obtain maximum load when the first metacarpal sinking 10 mm and to determine which Ligament reconstruction method yielded larger axial shortening resistance. Results After the trapezium excision, the maximum load of the dorsal radial Ligament reconstruction when the first metacarpal sinking 10 mm was (67.67±7.98) N and that of the anterior Oblique Ligament reconstruction was (77.11±8.25) N. The difference between two groups was significant (P<0.05). Conclusion After the trapezium excision, anterior Oblique Ligament reconstruction using flexor carpi radialis tendon can achieve more stable trapeziometacarpal joint. We should reconstruct the anterior Oblique Ligament firstly. Key words: Thumb; Carpometacarpal joints; Ligaments; Biomechanics
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Biomechanical comparison of anterior Oblique Ligament versus dorsal radial Ligament reconstruction of the trapeziometacarpal joint
Chinese Journal of Hand Surgery, 2017Co-Authors: Jingda Liu, Liang Zhao, Min ZhaoAbstract:Objective To compare the axial shortening resistance of anterior Oblique Ligament and dorsal radial Ligament reconstruction of trapeziometacarpal joint after trapezium excision for the patients with osteoarthritis of trapeziometacarpal joint, and to determine which method was more stable. Methods Twenty cases of male adult fresh cadaver hand specimens were dissected. After the trapezium excision, ten cases of anterior Oblique Ligament and ten cases of dorsal radial Ligament were reconstructed using half bundle of flexor carpi radialis tendon. Biomechanical testing was performed to obtain maximum load when the first metacarpal sinking 10 mm and to determine which Ligament reconstruction method yielded larger axial shortening resistance. Results After the trapezium excision, the maximum load of the dorsal radial Ligament reconstruction when the first metacarpal sinking 10 mm was (67.67±7.98) N and that of the anterior Oblique Ligament reconstruction was (77.11±8.25) N. The difference between two groups was significant (P
Elisabet Hagert - One of the best experts on this subject based on the ideXlab platform.
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Ultrastructure and Innervation of Thumb Carpometacarpal Ligaments in Surgical Patients With Osteoarthritis
Clinical orthopaedics and related research, 2014Co-Authors: Nathalie Mobargha, Amy L. Ladd, Cassie A. Ludwig, Elisabet HagertAbstract:Background The complex configuration of the thumb carpometacarpal (CMC-1) joint relies on musculotendinous and Ligamentous support for precise circumduction. Ligament innervation contributes to joint stability and proprioception. Evidence suggests abnormal Ligament innervation is associated with osteoarthritis (OA) in large joints; however, little is known about CMC-1 Ligament innervation characteristics in patients with OA. We studied the dorsal radial Ligament (DRL) and the anterior Oblique Ligament (AOL), Ligaments with a reported divergent presence of mechanoreceptors in nonosteoarthritic joints.
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Thumb carpometacarpal Ligaments inside and out: a comparative study of arthroscopic and gross anatomy from the robert a. Chase hand and upper limb center at stanford university.
Journal of wrist surgery, 2013Co-Authors: Andrew Y Zhang, Elisabet Hagert, Sarah Van Nortwick, Jeffrey Yao, Amy L. LaddAbstract:Purpose We propose to identify and correlate arthroscopic internal Ligaments with external Ligaments, providing an accurate roadmap for arthroscopic Ligament and joint anatomy. Ligamentous laxity is considered an important risk factor in developing the common basilar arthritis of the thumb. Controversy exists as to the precise Ligamentous anatomy of the thumb carpometacarpal (CMC) joint (CMC-I); description of the internal arthroscopic anatomy is limited. Methods We performed CMC-I joint arthroscopy using the 1-Ulnar (1U) and thenar portals in five cadavers, seeking to identify the following seven Ligaments arthroscopically: the superficial anterior Oblique Ligament (sAOL), deep anterior Oblique Ligament (dAOL), ulnar collateral Ligament (UCL), dorsal trapeziometacarpal Ligament (DTM-1), posterior Oblique Ligament (POL), dorsal central Ligament (DCL), and dorsal radial Ligament (DRL). After grading articular changes of the trapezium, we passed Kirschner wires (K-wires) (0.028) outside-in to mark the arthroscopic insertion of each Ligament on the trapezium. Gross dissection was performed to confirm the wire placement; the anatomic identity and position of joint stabilizing Ligaments, and the location of frequently used portals. Results The volar Ligaments-the sAOL, dAOL, and UCL-were highly variable in their arthroscopic appearance and precise location. The sAOL is a thin veil of membranous tissue that variably drapes across the anterior joint capsule. The reported dAOL and UCL, in our study, correlated to a thickened portion of this veil around the volar beak and was not consistently identified with gross dissection. In contrast, the arthroscopic appearance and location of the dorsal Ligaments-DTM-I, POL, DCL, and DRL-were consistent in all specimens. Conclusion Our study further defines and correlates the arthroscopic and external Ligamentous anatomy of the CMC-I joint.
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macroscopic and microscopic analysis of the thumb carpometacarpal Ligaments a cadaveric study of Ligament anatomy and histology
Journal of Bone and Joint Surgery American Volume, 2012Co-Authors: Amy L. Ladd, Elisabet HagertAbstract:Background: Stability and mobility represent the paradoxical demands of the human thumb carpometacarpal joint, yet the structural origin of each functional demand is poorly defined. As many as sixteen and as few as four Ligaments have been described as primary stabilizers, but controversy exists as to which Ligaments are most important. We hypothesized that a comparative macroscopic and microscopic analysis of the Ligaments of the thumb carpometacarpal joint would further define their role in joint stability. Methods: Thirty cadaveric hands (ten fresh-frozen and twenty embalmed) from nineteen cadavers (eight female and eleven male; average age at the time of death, seventy-six years) were dissected, and the supporting Ligaments of the thumb carpometacarpal joint were identified. Ligament width, length, and thickness were recorded for morphometric analysis and were compared with use of the Student t test. The dorsal and volar Ligaments were excised from the fresh-frozen specimens and were stained with use of a triple-staining immunofluorescent technique and underwent semiquantitative analysis of sensory innervation; half of these specimens were additionally analyzed for histomorphometric data. Mixed-effects linear regression was used to estimate differences between Ligaments. Results: Seven principal Ligaments of the thumb carpometacarpal joint were identified: three dorsal deltoid-shaped Ligaments (dorsal radial, dorsal central, posterior Oblique), two volar Ligaments (anterior Oblique and ulnar collateral), and two ulnar Ligaments (dorsal trapeziometacarpal and intermetacarpal). The dorsal Ligaments were significantly thicker (p < 0.001) than the volar Ligaments, with a significantly greater cellularity and greater sensory innervation compared with the anterior Oblique Ligament (p < 0.001). The anterior Oblique Ligament was consistently a thin structure with a histologic appearance of capsular tissue with low cellularity. Conclusions: The dorsal deltoid Ligament complex is uniformly stout and robust; this Ligament complex is the thickest morphometrically, has the highest cellularity histologically, and shows the greatest degree of sensory nerve endings. The hypocellular anterior Oblique Ligament is thin, is variable in its location, and is more structurally consistent with a capsular structure than a proper Ligament. Clinical Relevance: Delineation of the structural and microscopic anatomy of the Ligaments of the thumb carpometacarpal joint provides further evidence regarding the stability and mobility of this joint that is often affected by osteoarthritis.
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Innervation patterns of thumb trapeziometacarpal joint Ligaments.
The Journal of hand surgery, 2012Co-Authors: Elisabet Hagert, Julia Lee, Amy L. LaddAbstract:Purpose The human thumb trapeziometacarpal (TM) joint is a unique articulation that allows stability during pinch and grip and great degrees of mobility. Because the saddle-shaped articulating surfaces of the TM joint are inherently unstable, joint congruity depends on the action of restraining Ligaments and periarticular muscles. From other joints, it is known that proprioceptive and neuromuscular joint stability depend on afferent information from nerve endings within Ligaments. We hypothesize that the TM joint Ligaments may similarly be innervated, indicating a possible proprioceptive function of the joint. Methods We harvested 5 TM joint Ligaments in entirety from 10 fresh-frozen cadaver hands with no or only minor signs of osteoarthritis and suture-marked them for proximal-distal orientation. The Ligaments harvested were the dorsal radial, dorsal central, posterior Oblique, ulnar collateral, and anterior Oblique Ligaments. After paraffin-sectioning, we stained the Ligaments using a triple-antibody immunofluorescent technique and analyzed them using immunofluorescence microscopy. Results Using the triple-stain technique, mechanoreceptors could be classified as Pacinian corpuscles, Ruffini endings, or Golgi-like endings. The 3 dorsal Ligaments had significantly more nerve endings than the 2 volar Ligaments. Most of the nerve endings were close to the bony attachments and significantly closer ( P = .010) to the metacarpal insertion of each Ligament. The anterior Oblique Ligament had little to no innervation in any of the specimens analyzed. Discussion The TM joint Ligaments had an abundance of nerve endings in the dorsal Ligaments but little to no innervation in the anterior Oblique Ligament. The Ruffini ending was the predominant mechanoreceptor type, with a greater density in the mobile metacarpal portion of each Ligament. Clinical relevance Presence of mechanoreceptors in the dorsal TM joint Ligaments infers a proprioceptive function of these Ligaments in addition to their biomechanical importance in TM joint stability.
Jingda Liu - One of the best experts on this subject based on the ideXlab platform.
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biomechanical comparison of anterior Oblique Ligament versus dorsal radial Ligament reconstruction of the trapeziometacarpal joint
Chinese Journal of Hand Surgery, 2017Co-Authors: Jingda Liu, Liang Zhao, Min ZhaoAbstract:Objective To compare the axial shortening resistance of anterior Oblique Ligament and dorsal radial Ligament reconstruction of trapeziometacarpal joint after trapezium excision for the patients with osteoarthritis of trapeziometacarpal joint, and to determine which method was more stable. Methods Twenty cases of male adult fresh cadaver hand specimens were dissected. After the trapezium excision, ten cases of anterior Oblique Ligament and ten cases of dorsal radial Ligament were reconstructed using half bundle of flexor carpi radialis tendon. Biomechanical testing was performed to obtain maximum load when the first metacarpal sinking 10 mm and to determine which Ligament reconstruction method yielded larger axial shortening resistance. Results After the trapezium excision, the maximum load of the dorsal radial Ligament reconstruction when the first metacarpal sinking 10 mm was (67.67±7.98) N and that of the anterior Oblique Ligament reconstruction was (77.11±8.25) N. The difference between two groups was significant (P<0.05). Conclusion After the trapezium excision, anterior Oblique Ligament reconstruction using flexor carpi radialis tendon can achieve more stable trapeziometacarpal joint. We should reconstruct the anterior Oblique Ligament firstly. Key words: Thumb; Carpometacarpal joints; Ligaments; Biomechanics
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Biomechanical comparison of anterior Oblique Ligament versus dorsal radial Ligament reconstruction of the trapeziometacarpal joint
Chinese Journal of Hand Surgery, 2017Co-Authors: Jingda Liu, Liang Zhao, Min ZhaoAbstract:Objective To compare the axial shortening resistance of anterior Oblique Ligament and dorsal radial Ligament reconstruction of trapeziometacarpal joint after trapezium excision for the patients with osteoarthritis of trapeziometacarpal joint, and to determine which method was more stable. Methods Twenty cases of male adult fresh cadaver hand specimens were dissected. After the trapezium excision, ten cases of anterior Oblique Ligament and ten cases of dorsal radial Ligament were reconstructed using half bundle of flexor carpi radialis tendon. Biomechanical testing was performed to obtain maximum load when the first metacarpal sinking 10 mm and to determine which Ligament reconstruction method yielded larger axial shortening resistance. Results After the trapezium excision, the maximum load of the dorsal radial Ligament reconstruction when the first metacarpal sinking 10 mm was (67.67±7.98) N and that of the anterior Oblique Ligament reconstruction was (77.11±8.25) N. The difference between two groups was significant (P
Lars Engebretsen - One of the best experts on this subject based on the ideXlab platform.
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Injuries to the Medial Collateral Ligament and Associated Medial Structures of the Knee
The Journal of bone and joint surgery. American volume, 2010Co-Authors: Coen A. Wijdicks, Chad J Griffith, Steinar Johansen, Lars Engebretsen, Robert F. LapradeAbstract:*The superficial medial collateral Ligament and other medial knee stabilizers-i.e., the deep medial collateral Ligament and the posterior Oblique Ligament-are the most commonly injured Ligamentous structures of the knee. *The main structures of the medial aspect of the knee are the proximal and distal divisions of the superficial medial collateral Ligament, the meniscofemoral and meniscotibial divisions of the deep medial collateral Ligament, and the posterior Oblique Ligament. *Physical examination is the initial method of choice for the diagnosis of medial knee injuries through the application of a valgus load both at full knee extension and between 20 degrees and 30 degrees of knee flexion. *Because nonoperative treatment has a favorable outcome, there is a consensus that it should be the first step in the management of acute isolated grade-III injuries of the medial collateral Ligament or such injuries combined with an anterior cruciate Ligament tear. *If operative treatment is required, an anatomic repair or reconstruction is recommended.
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medial knee injury part 2 load sharing between the posterior Oblique Ligament and superficial medial collateral Ligament
American Journal of Sports Medicine, 2009Co-Authors: Coen A. Wijdicks, Robert F. Laprade, Chad J Griffith, Steinar Johansen, Stanislav I Spiridonov, Bryan M Armitage, Lars EngebretsenAbstract:BackgroundThere is limited information regarding directly measured load responses of the posterior Oblique and superficial medial collateral Ligaments in isolated and multiple medial knee Ligament injury states.HypothesesTensile load responses from both the superficial medial collateral Ligament and the posterior Oblique Ligament would be measurable and reproducible, and the native load-sharing relationships between these Ligaments would be altered after sectioning of medial knee structures.Study DesignDescriptive laboratory study.MethodsTwenty-four nonpaired, fresh-frozen adult cadaveric knees were distributed into 3 sequential sectioning sequences. Buckle transducers were applied to the posterior Oblique Ligament and the proximal and distal divisions of the superficial medial collateral Ligament; 10 N·m valgus moments and 5 N·m internal and external rotation torques were applied at 0°, 20°, 30°, 60°, and 90° of knee flexion.ResultsWith an applied valgus and external rotation moment, there was a signific...
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part 2 load sharing between the posterior Oblique Ligament and superficial medial collateral Ligament
2009Co-Authors: Coen A. Wijdicks, Robert F. Laprade, Chad J Griffith, Steinar Johansen, Stanislav I Spiridonov, Bryan M Armitage, Lars EngebretsenAbstract:Results: With an applied valgus and external rotation moment, there was a significant load increase on the posterior Oblique Ligament compared with the intact state after sectioning all other medial knee structures. With an applied external rotation torque, there was a significant load decrease on the proximal division of the superficial medial collateral Ligament from the intact state after sectioning all other medial knee structures. With an applied external rotation torque, the distal division of the superficial medial collateral Ligament experienced a significant load increase from the intact state after sectioning the posterior Oblique Ligament and the meniscofemoral division of the deep medial collateral Ligament. Conclusion: This study found alterations in the native load-sharing relationships of the medial knee structures after injury. Sectioning both the primary and secondary restraints to valgus and internal/external rotation of the knee alters the intricate load- sharing relationships that exist between the medial knee structures. Clinical Significance: In cases in which surgical repair or reconstruction is indicated, consideration should be placed on repair- ing or reconstructing all injured medial knee structures to restore the native load-sharing relationships among these medial knee structures.
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force measurements on the posterior Oblique Ligament and superficial medial collateral Ligament proximal and distal divisions to applied loads
American Journal of Sports Medicine, 2009Co-Authors: Chad J Griffith, Robert F. Laprade, Coen A. Wijdicks, Steinar Johansen, Bryan M Armitage, Lars EngebretsenAbstract:BackgroundThere is limited information regarding load responses of the posterior Oblique and superficial medial collateral Ligaments to applied loads.HypothesesThe degree of knee flexion affects loads experienced by the posterior Oblique Ligament and both divisions of the superficial medial collateral Ligament. The posterior Oblique Ligament provides significant resistance to valgus and internal rotation forces near knee extension. Different load responses are experienced by proximal and distal divisions of the superficial medial collateral Ligament.Study DesignDescriptive laboratory study.MethodsTwenty-four nonpaired, fresh-frozen cadaveric knees were tested. Buckle transducers were applied to the proximal and distal divisions of the superficial medial collateral and posterior Oblique Ligaments. Applied loads at 0°, 20°, 30°, 60°, and 90° of knee flexion consisted of 10 N.m valgus loads, 5 N .m internal and external rotation torques, and 88 N anterior and posterior drawer loads.ResultsExternal rotation t...
Amy L. Ladd - One of the best experts on this subject based on the ideXlab platform.
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Ultrastructure and Innervation of Thumb Carpometacarpal Ligaments in Surgical Patients With Osteoarthritis
Clinical orthopaedics and related research, 2014Co-Authors: Nathalie Mobargha, Amy L. Ladd, Cassie A. Ludwig, Elisabet HagertAbstract:Background The complex configuration of the thumb carpometacarpal (CMC-1) joint relies on musculotendinous and Ligamentous support for precise circumduction. Ligament innervation contributes to joint stability and proprioception. Evidence suggests abnormal Ligament innervation is associated with osteoarthritis (OA) in large joints; however, little is known about CMC-1 Ligament innervation characteristics in patients with OA. We studied the dorsal radial Ligament (DRL) and the anterior Oblique Ligament (AOL), Ligaments with a reported divergent presence of mechanoreceptors in nonosteoarthritic joints.
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Thumb carpometacarpal Ligaments inside and out: a comparative study of arthroscopic and gross anatomy from the robert a. Chase hand and upper limb center at stanford university.
Journal of wrist surgery, 2013Co-Authors: Andrew Y Zhang, Elisabet Hagert, Sarah Van Nortwick, Jeffrey Yao, Amy L. LaddAbstract:Purpose We propose to identify and correlate arthroscopic internal Ligaments with external Ligaments, providing an accurate roadmap for arthroscopic Ligament and joint anatomy. Ligamentous laxity is considered an important risk factor in developing the common basilar arthritis of the thumb. Controversy exists as to the precise Ligamentous anatomy of the thumb carpometacarpal (CMC) joint (CMC-I); description of the internal arthroscopic anatomy is limited. Methods We performed CMC-I joint arthroscopy using the 1-Ulnar (1U) and thenar portals in five cadavers, seeking to identify the following seven Ligaments arthroscopically: the superficial anterior Oblique Ligament (sAOL), deep anterior Oblique Ligament (dAOL), ulnar collateral Ligament (UCL), dorsal trapeziometacarpal Ligament (DTM-1), posterior Oblique Ligament (POL), dorsal central Ligament (DCL), and dorsal radial Ligament (DRL). After grading articular changes of the trapezium, we passed Kirschner wires (K-wires) (0.028) outside-in to mark the arthroscopic insertion of each Ligament on the trapezium. Gross dissection was performed to confirm the wire placement; the anatomic identity and position of joint stabilizing Ligaments, and the location of frequently used portals. Results The volar Ligaments-the sAOL, dAOL, and UCL-were highly variable in their arthroscopic appearance and precise location. The sAOL is a thin veil of membranous tissue that variably drapes across the anterior joint capsule. The reported dAOL and UCL, in our study, correlated to a thickened portion of this veil around the volar beak and was not consistently identified with gross dissection. In contrast, the arthroscopic appearance and location of the dorsal Ligaments-DTM-I, POL, DCL, and DRL-were consistent in all specimens. Conclusion Our study further defines and correlates the arthroscopic and external Ligamentous anatomy of the CMC-I joint.
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macroscopic and microscopic analysis of the thumb carpometacarpal Ligaments a cadaveric study of Ligament anatomy and histology
Journal of Bone and Joint Surgery American Volume, 2012Co-Authors: Amy L. Ladd, Elisabet HagertAbstract:Background: Stability and mobility represent the paradoxical demands of the human thumb carpometacarpal joint, yet the structural origin of each functional demand is poorly defined. As many as sixteen and as few as four Ligaments have been described as primary stabilizers, but controversy exists as to which Ligaments are most important. We hypothesized that a comparative macroscopic and microscopic analysis of the Ligaments of the thumb carpometacarpal joint would further define their role in joint stability. Methods: Thirty cadaveric hands (ten fresh-frozen and twenty embalmed) from nineteen cadavers (eight female and eleven male; average age at the time of death, seventy-six years) were dissected, and the supporting Ligaments of the thumb carpometacarpal joint were identified. Ligament width, length, and thickness were recorded for morphometric analysis and were compared with use of the Student t test. The dorsal and volar Ligaments were excised from the fresh-frozen specimens and were stained with use of a triple-staining immunofluorescent technique and underwent semiquantitative analysis of sensory innervation; half of these specimens were additionally analyzed for histomorphometric data. Mixed-effects linear regression was used to estimate differences between Ligaments. Results: Seven principal Ligaments of the thumb carpometacarpal joint were identified: three dorsal deltoid-shaped Ligaments (dorsal radial, dorsal central, posterior Oblique), two volar Ligaments (anterior Oblique and ulnar collateral), and two ulnar Ligaments (dorsal trapeziometacarpal and intermetacarpal). The dorsal Ligaments were significantly thicker (p < 0.001) than the volar Ligaments, with a significantly greater cellularity and greater sensory innervation compared with the anterior Oblique Ligament (p < 0.001). The anterior Oblique Ligament was consistently a thin structure with a histologic appearance of capsular tissue with low cellularity. Conclusions: The dorsal deltoid Ligament complex is uniformly stout and robust; this Ligament complex is the thickest morphometrically, has the highest cellularity histologically, and shows the greatest degree of sensory nerve endings. The hypocellular anterior Oblique Ligament is thin, is variable in its location, and is more structurally consistent with a capsular structure than a proper Ligament. Clinical Relevance: Delineation of the structural and microscopic anatomy of the Ligaments of the thumb carpometacarpal joint provides further evidence regarding the stability and mobility of this joint that is often affected by osteoarthritis.
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Innervation patterns of thumb trapeziometacarpal joint Ligaments.
The Journal of hand surgery, 2012Co-Authors: Elisabet Hagert, Julia Lee, Amy L. LaddAbstract:Purpose The human thumb trapeziometacarpal (TM) joint is a unique articulation that allows stability during pinch and grip and great degrees of mobility. Because the saddle-shaped articulating surfaces of the TM joint are inherently unstable, joint congruity depends on the action of restraining Ligaments and periarticular muscles. From other joints, it is known that proprioceptive and neuromuscular joint stability depend on afferent information from nerve endings within Ligaments. We hypothesize that the TM joint Ligaments may similarly be innervated, indicating a possible proprioceptive function of the joint. Methods We harvested 5 TM joint Ligaments in entirety from 10 fresh-frozen cadaver hands with no or only minor signs of osteoarthritis and suture-marked them for proximal-distal orientation. The Ligaments harvested were the dorsal radial, dorsal central, posterior Oblique, ulnar collateral, and anterior Oblique Ligaments. After paraffin-sectioning, we stained the Ligaments using a triple-antibody immunofluorescent technique and analyzed them using immunofluorescence microscopy. Results Using the triple-stain technique, mechanoreceptors could be classified as Pacinian corpuscles, Ruffini endings, or Golgi-like endings. The 3 dorsal Ligaments had significantly more nerve endings than the 2 volar Ligaments. Most of the nerve endings were close to the bony attachments and significantly closer ( P = .010) to the metacarpal insertion of each Ligament. The anterior Oblique Ligament had little to no innervation in any of the specimens analyzed. Discussion The TM joint Ligaments had an abundance of nerve endings in the dorsal Ligaments but little to no innervation in the anterior Oblique Ligament. The Ruffini ending was the predominant mechanoreceptor type, with a greater density in the mobile metacarpal portion of each Ligament. Clinical relevance Presence of mechanoreceptors in the dorsal TM joint Ligaments infers a proprioceptive function of these Ligaments in addition to their biomechanical importance in TM joint stability.
