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Keiichi Akita - One of the best experts on this subject based on the ideXlab platform.
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anatomic analysis of the whole Articular Capsule of the shoulder joint with reference to the capsular attachment and thickness
Journal of Experimental Orthopaedics, 2018Co-Authors: Daisuke Momma, Akimoto Nimura, Hitomi Fujishiro, Satoru Muro, Takashi Miyamoto, Tadanao Funakoshi, Tomoyuki Mochizuki, Norimasa Iwasaki, Keiichi AkitaAbstract:Although conventional Bankart repair has been the accepted procedure for traumatic anterior glenohumeral instability, the humeral avulsion of the glenohumeral ligament or an elongation of the Capsule remains challenging to decide the appropriate treatment. The anatomical knowledge regarding the whole Capsule of glenohumeral joint is necessary to accurately treat for the capsular disorders. The aims of the current study were to investigate the anatomical features of capsular attachment and thickness in a whole Capsule of glenohumeral joint. We used 13 shoulders in the current study. In 9 shoulders, we macroscopically measured the attachment widths of the capsulolabrum complex on the scapular glenoid, and the attachment widths of the Capsule on the humerus in reference to the scapular origin of the long head of triceps brachii, and the humeral insertion of the rotator cuff tendons. We additionally used 4 cadaveric shoulders, which were embalmed using Thiel’s method, for the analysis of the thickness in a whole Capsule by using micro-CT. The glenoidal attachment of the Articular Capsule appeared to have a consistent width except for the superior part of the origin of the long head of triceps brachii. On the humerus, the Articular Capsule was widely attached to areas without overlying rotator cuffs, with the widest width (17.3 ± 0.9 mm) attached to the axillary pouch. The inferior part of the Capsule, which was consistently thicker than the superior part, continued to the superior part along the glenoid and humeral side edge. The current study showed that the inferior part of the glenohumeral Capsule had a wide humeral attachment from the inferior edge of the subscapularis insertion to the inferior edge of the teres minor insertion via the anatomical neck of the humerus, and the thickness of it was thicker than the superior part of the Capsule.
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Anatomic analysis of the whole Articular Capsule of the shoulder joint, with reference to the capsular attachment and thickness
'Springer Science and Business Media LLC', 2018Co-Authors: Daisuke Momma, Akimoto Nimura, Hitomi Fujishiro, Satoru Muro, Takashi Miyamoto, Tadanao Funakoshi, Tomoyuki Mochizuki, Norimasa Iwasaki, Keiichi AkitaAbstract:Abstract Background Although conventional Bankart repair has been the accepted procedure for traumatic anterior glenohumeral instability, the humeral avulsion of the glenohumeral ligament or an elongation of the Capsule remains challenging to decide the appropriate treatment. The anatomical knowledge regarding the whole Capsule of glenohumeral joint is necessary to accurately treat for the capsular disorders. The aims of the current study were to investigate the anatomical features of capsular attachment and thickness in a whole Capsule of glenohumeral joint. Methods We used 13 shoulders in the current study. In 9 shoulders, we macroscopically measured the attachment widths of the capsulolabrum complex on the scapular glenoid, and the attachment widths of the Capsule on the humerus in reference to the scapular origin of the long head of triceps brachii, and the humeral insertion of the rotator cuff tendons. We additionally used 4 cadaveric shoulders, which were embalmed using Thiel’s method, for the analysis of the thickness in a whole Capsule by using micro-CT. Results The glenoidal attachment of the Articular Capsule appeared to have a consistent width except for the superior part of the origin of the long head of triceps brachii. On the humerus, the Articular Capsule was widely attached to areas without overlying rotator cuffs, with the widest width (17.3 ± 0.9 mm) attached to the axillary pouch. The inferior part of the Capsule, which was consistently thicker than the superior part, continued to the superior part along the glenoid and humeral side edge. Conclusions The current study showed that the inferior part of the glenohumeral Capsule had a wide humeral attachment from the inferior edge of the subscapularis insertion to the inferior edge of the teres minor insertion via the anatomical neck of the humerus, and the thickness of it was thicker than the superior part of the Capsule
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joint Capsule attachment to the extensor carpi radialis brevis origin an anatomical study with possible implications regarding the etiology of lateral epicondylitis
Journal of Hand Surgery (European Volume), 2014Co-Authors: Akimoto Nimura, Hitomi Fujishiro, Junya Imatani, Yoshiaki Wakabayashi, Hiroyuki Sugaya, Keiichi AkitaAbstract:Purpose To identify the unique anatomical characteristic of the extensor carpi radialis brevis (ECRB) origin and points of differentiation from other extensors and to clarify the specific relationship of the ECRB to the underlying structures. Methods We studied the origin of each extensor macroscopically for its muscular and tendinous parts; to identify the relationship between the ECRB origin and the deeper structures, we also examined the attachment of the joint Capsule under the ECRB origin. Results The ECRB simply originated as a tendon without any muscle, whereas other extensors originated as a mixture of tendon and muscle. At the anterior part of the ECRB origin, the thin attachment of the joint Capsule (average width, 3.3 mm) lay deep to the ECRB and was distinct. However, at the posterodistal portion, the joint Capsule, annular ligament, and supinator were intermingled and originated as a single wide sheet from the humerus (average width, 10.7 mm). Conclusions The anterior part of the ECRB origin was delicate, because the ECRB origin was purely tendinous, and the attachment of the Articular Capsule was thin compared with that of the posterodistal attachment. This thin attachment could be an initial factor leading to the development of lateral epicondylitis. Clinical relevance The results of the current study may enhance magnetic resonance imaging understanding and may help clarify the etiology of the lateral epicondylitis.
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the superior Capsule of the shoulder joint complements the insertion of the rotator cuff
Journal of Shoulder and Elbow Surgery, 2012Co-Authors: Akimoto Nimura, Hiroyuki Sugaya, Tomoyuki Mochizuki, Atsuo Kato, Kumiko Yamaguchi, Atsushi Okawa, Keiichi AkitaAbstract:Background To date, there are no studies about the attachment of the Articular Capsule of the superior shoulder joint. The aim of this study was to measure the width of the attachment of the Articular Capsule on the humerus, and to clarify the anatomy and the relationship to the footprint of the rotator cuff. Methods The attachment of the Articular Capsule on the greater tuberosity was exposed. The width of the attachment of the Capsule and the footprint of the rotator cuff were measured. Results The maximum capsular width was located at the border between the infraspinatus and the teres minor, and measured 9.1 mm. The minimum capsular width was 3.5 mm, and it was located at 10.9 mm posterior to the anterior margin of the greater tuberosity and 1.5 mm anterior to the posterior margin of the supraspinatus. Conclusion Prior studies have overestimated the rotator cuff footprint width due to the lack of discrimination between the actual cuff insertion and Capsule. The attachment of the Articular Capsule of the shoulder joint occupied a substantial area of the greater tuberosity. In pArticular, at the border between the infraspinatus and the teres minor, the very thick attachment of the Articular Capsule compensated for the lack of attachment of muscular components. The thinnest point of the Articular Capsule was 11 mm posterior to the anterior margin of the greater tuberosity and very close to the posterior edge of the tapered insertion of the supraspinatus, which could contribute to the etiology of degenerative rotator cuff tears.
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Positional relationships between the masticatory muscles and their innervating nerves with special reference to the lateral pterygoid and the midmedial and discotemporal muscle bundles of temporalis.
Journal of Anatomy, 2000Co-Authors: Keiichi Akita, Takashi Shimokawa, Tatsuo SatoAbstract:For an accurate assessment of jaw movement, it is crucial to understand the comprehensive formation of the masticatory muscles with special reference to the relationship to the disc of the temporomandibular joint. Detailed dissection was performed on 26 head halves of 14 Japanese cadavers in order to obtain precise anatomical information of the positional relationships between the masticatory muscles and the branches of the mandibular nerve. After complete removal of the bony elements, the midmedial muscle bundle in all specimens and the discotemporal muscle bundle in 6 specimens, derivatives of the temporalis, which insert into the disc were observed. On the anterior area of the Articular Capsule and the disc of the temporomandibular joint, the upper head of the lateral pterygoid, the midmedial muscle bundle of temporalis and the discotemporal bundle of temporalis were attached mediolaterally, and in 3 specimens the posterosuperior margin of the zygomaticomandibularis was attached to the anterolateral area of the disc. It is suggested that these muscles and muscle bundles contribute to various mandibular movements. Although various patterns of the positional relationships between the muscles and muscle bundles and the their innervating nerves are observed in the present study, relative positional relationships of the muscles and muscle bundles and of nerves of the mandibular nerve are consistent. A possible scheme of the developmental formation of the masticatory muscles based on the findings of the positional relationships between the muscles and the nerves is presented.
Shogo Kikuta - One of the best experts on this subject based on the ideXlab platform.
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A new variant ligament of the atlantooccipital joint: the lateral oblique atlantooccipital ligament
European Spine Journal, 2019Co-Authors: Shogo Kikuta, Joe Iwanaga, Rod J Oskouian, R. Shane TubbsAbstract:Purpose During routine dissection of the anterior craniocervical junction (CCJ), a variant ligament just anterior to the Articular Capsule of the atlantooccipital joint was observed. To our knowledge, no literature has previously described this ligament. Therefore, the aim of this study was to clarify the anatomy, incidence, and biomechanics of this undescribed structure of the anterior atlantooccipital joint. Methods Twenty-six sides from 13 fresh-frozen adult cadavers were used for this study and the morphology of the variant ligament examined. When present, its length, width, thickness, and the angle from the midline of the CCJ were measured. Results The variant ligament identified, when present, is distinct and located anterior to the atlantooccipital joint Capsule traveling between the occipital bone and the transverse process of the atlas. The ligament was found on 12 of 26 sides (46.2%). The mean length of the ligament was 32.0 ± 5.5 mm. The ligament became taut with contralateral lateral flexion and the ipsilateral rotation of the atlantooccipital joint. Conclusions We propose that this ligament may be termed the lateral oblique atlantooccipital ligament. To date, this structure has not been described in any textbooks or reports in the extant medical literature. Although its function is not clear, based on its course and connections, it might function as a secondary stabilizer of the atlantooccipital joint. As the stability of the craniocervical junction is of paramount importance, knowledge of normal and variant anatomical structures in this region is important for the surgeon treating patients with pathology of this region. Graphical abstract These slides can be retrieved under Electronic Supplementary Material.
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a new variant ligament of the atlantooccipital joint the lateral oblique atlantooccipital ligament
European Spine Journal, 2019Co-Authors: Shogo Kikuta, Joe Iwanaga, Rod J Oskouian, Shane R TubbsAbstract:Purpose During routine dissection of the anterior craniocervical junction (CCJ), a variant ligament just anterior to the Articular Capsule of the atlantooccipital joint was observed. To our knowledge, no literature has previously described this ligament. Therefore, the aim of this study was to clarify the anatomy, incidence, and biomechanics of this undescribed structure of the anterior atlantooccipital joint.
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a new variant ligament of the atlantooccipital joint the lateral oblique atlantooccipital ligament
European Spine Journal, 2019Co-Authors: Shogo Kikuta, Joe Iwanaga, Rod J Oskouian, Shane R TubbsAbstract:During routine dissection of the anterior craniocervical junction (CCJ), a variant ligament just anterior to the Articular Capsule of the atlantooccipital joint was observed. To our knowledge, no literature has previously described this ligament. Therefore, the aim of this study was to clarify the anatomy, incidence, and biomechanics of this undescribed structure of the anterior atlantooccipital joint. Twenty-six sides from 13 fresh-frozen adult cadavers were used for this study and the morphology of the variant ligament examined. When present, its length, width, thickness, and the angle from the midline of the CCJ were measured. The variant ligament identified, when present, is distinct and located anterior to the atlantooccipital joint Capsule traveling between the occipital bone and the transverse process of the atlas. The ligament was found on 12 of 26 sides (46.2%). The mean length of the ligament was 32.0 ± 5.5 mm. The ligament became taut with contralateral lateral flexion and the ipsilateral rotation of the atlantooccipital joint. We propose that this ligament may be termed the lateral oblique atlantooccipital ligament. To date, this structure has not been described in any textbooks or reports in the extant medical literature. Although its function is not clear, based on its course and connections, it might function as a secondary stabilizer of the atlantooccipital joint. As the stability of the craniocervical junction is of paramount importance, knowledge of normal and variant anatomical structures in this region is important for the surgeon treating patients with pathology of this region. These slides can be retrieved under Electronic Supplementary Material.
Shane R Tubbs - One of the best experts on this subject based on the ideXlab platform.
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a new variant ligament of the atlantooccipital joint the lateral oblique atlantooccipital ligament
European Spine Journal, 2019Co-Authors: Shogo Kikuta, Joe Iwanaga, Rod J Oskouian, Shane R TubbsAbstract:Purpose During routine dissection of the anterior craniocervical junction (CCJ), a variant ligament just anterior to the Articular Capsule of the atlantooccipital joint was observed. To our knowledge, no literature has previously described this ligament. Therefore, the aim of this study was to clarify the anatomy, incidence, and biomechanics of this undescribed structure of the anterior atlantooccipital joint.
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a new variant ligament of the atlantooccipital joint the lateral oblique atlantooccipital ligament
European Spine Journal, 2019Co-Authors: Shogo Kikuta, Joe Iwanaga, Rod J Oskouian, Shane R TubbsAbstract:During routine dissection of the anterior craniocervical junction (CCJ), a variant ligament just anterior to the Articular Capsule of the atlantooccipital joint was observed. To our knowledge, no literature has previously described this ligament. Therefore, the aim of this study was to clarify the anatomy, incidence, and biomechanics of this undescribed structure of the anterior atlantooccipital joint. Twenty-six sides from 13 fresh-frozen adult cadavers were used for this study and the morphology of the variant ligament examined. When present, its length, width, thickness, and the angle from the midline of the CCJ were measured. The variant ligament identified, when present, is distinct and located anterior to the atlantooccipital joint Capsule traveling between the occipital bone and the transverse process of the atlas. The ligament was found on 12 of 26 sides (46.2%). The mean length of the ligament was 32.0 ± 5.5 mm. The ligament became taut with contralateral lateral flexion and the ipsilateral rotation of the atlantooccipital joint. We propose that this ligament may be termed the lateral oblique atlantooccipital ligament. To date, this structure has not been described in any textbooks or reports in the extant medical literature. Although its function is not clear, based on its course and connections, it might function as a secondary stabilizer of the atlantooccipital joint. As the stability of the craniocervical junction is of paramount importance, knowledge of normal and variant anatomical structures in this region is important for the surgeon treating patients with pathology of this region. These slides can be retrieved under Electronic Supplementary Material.
Donald Resnick - One of the best experts on this subject based on the ideXlab platform.
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accessory head of biceps brachii muscle anatomy histology and mri in cadavers
American Journal of Roentgenology, 2010Co-Authors: Ramon Gheno, Cristiane S Zoner, Florian M Buck, Marcelo A C Nico, Parviz Haghighi, Debra Trudell, Donald ResnickAbstract:OBJECTIVE: The purpose of our study is to describe and define an anatomic variation located close to the bicipital groove using MRI with gross anatomic and histologic correlation in cadavers. MATERIALS AND METHODS: Ten fresh male human shoulders were harvested and used in this investigation. They were derived from persons with a mean age of death of 78.9 years (age range, 58-92 years). MR arthrography using proton density-weighted sequences was used to obtain images in axial, coronal, and sagittal planes. After imaging, the specimens were cut in axial, coronal, and sagittal sections using a band saw. The slices were then photographed to allow correlation with the MR arthrographic images, followed by histologic analysis. RESULTS: Two anomalous tendons, both intimate with the tendon of the long head of the biceps brachii muscle in the bicipital groove, were recognized. The origin of both tendons was in the greater tuberosity near the Articular Capsule. These structures had a muscular belly that was joined with the other biceps bellies. At the level of the bicipital groove, the anomalous tendons appeared as hypointense structures in proton density-weighted images, with a mostly flat morphology in axial and coronal planes. The average dimensions of these structures were 45.5 (craniocaudal)x6.2 (anteroposterior)x0.85 (mediolateral) mm. CONCLUSION: The MR images, gross anatomic inspection, and histologic information led us to conclude that these anomalous structures were accessory heads of the biceps brachii muscle.
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accessory head of biceps brachii muscle anatomy histology and mri in cadavers
American Journal of Roentgenology, 2010Co-Authors: Ramon Gheno, Cristiane S Zoner, Florian M Buck, Marcelo A C Nico, Parviz Haghighi, Debra Trudell, Donald ResnickAbstract:OBJECTIVE. The purpose of our study is to describe and define an anatomic variation located close to the bicipital groove using MRI with gross anatomic and histologic correlation in cadavers.MATERIALS AND METHODS. Ten fresh male human shoulders were harvested and used in this investigation. They were derived from persons with a mean age of death of 78.9 years (age range, 58–92 years). MR arthrography using proton density–weighted sequences was used to obtain images in axial, coronal, and sagittal planes. After imaging, the specimens were cut in axial, coronal, and sagittal sections using a band saw. The slices were then photographed to allow correlation with the MR arthrographic images, followed by histologic analysis.RESULTS. Two anomalous tendons, both intimate with the tendon of the long head of the biceps brachii muscle in the bicipital groove, were recognized. The origin of both tendons was in the greater tuberosity near the Articular Capsule. These structures had a muscular belly that was joined wit...
Rod J Oskouian - One of the best experts on this subject based on the ideXlab platform.
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A new variant ligament of the atlantooccipital joint: the lateral oblique atlantooccipital ligament
European Spine Journal, 2019Co-Authors: Shogo Kikuta, Joe Iwanaga, Rod J Oskouian, R. Shane TubbsAbstract:Purpose During routine dissection of the anterior craniocervical junction (CCJ), a variant ligament just anterior to the Articular Capsule of the atlantooccipital joint was observed. To our knowledge, no literature has previously described this ligament. Therefore, the aim of this study was to clarify the anatomy, incidence, and biomechanics of this undescribed structure of the anterior atlantooccipital joint. Methods Twenty-six sides from 13 fresh-frozen adult cadavers were used for this study and the morphology of the variant ligament examined. When present, its length, width, thickness, and the angle from the midline of the CCJ were measured. Results The variant ligament identified, when present, is distinct and located anterior to the atlantooccipital joint Capsule traveling between the occipital bone and the transverse process of the atlas. The ligament was found on 12 of 26 sides (46.2%). The mean length of the ligament was 32.0 ± 5.5 mm. The ligament became taut with contralateral lateral flexion and the ipsilateral rotation of the atlantooccipital joint. Conclusions We propose that this ligament may be termed the lateral oblique atlantooccipital ligament. To date, this structure has not been described in any textbooks or reports in the extant medical literature. Although its function is not clear, based on its course and connections, it might function as a secondary stabilizer of the atlantooccipital joint. As the stability of the craniocervical junction is of paramount importance, knowledge of normal and variant anatomical structures in this region is important for the surgeon treating patients with pathology of this region. Graphical abstract These slides can be retrieved under Electronic Supplementary Material.
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a new variant ligament of the atlantooccipital joint the lateral oblique atlantooccipital ligament
European Spine Journal, 2019Co-Authors: Shogo Kikuta, Joe Iwanaga, Rod J Oskouian, Shane R TubbsAbstract:Purpose During routine dissection of the anterior craniocervical junction (CCJ), a variant ligament just anterior to the Articular Capsule of the atlantooccipital joint was observed. To our knowledge, no literature has previously described this ligament. Therefore, the aim of this study was to clarify the anatomy, incidence, and biomechanics of this undescribed structure of the anterior atlantooccipital joint.
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a new variant ligament of the atlantooccipital joint the lateral oblique atlantooccipital ligament
European Spine Journal, 2019Co-Authors: Shogo Kikuta, Joe Iwanaga, Rod J Oskouian, Shane R TubbsAbstract:During routine dissection of the anterior craniocervical junction (CCJ), a variant ligament just anterior to the Articular Capsule of the atlantooccipital joint was observed. To our knowledge, no literature has previously described this ligament. Therefore, the aim of this study was to clarify the anatomy, incidence, and biomechanics of this undescribed structure of the anterior atlantooccipital joint. Twenty-six sides from 13 fresh-frozen adult cadavers were used for this study and the morphology of the variant ligament examined. When present, its length, width, thickness, and the angle from the midline of the CCJ were measured. The variant ligament identified, when present, is distinct and located anterior to the atlantooccipital joint Capsule traveling between the occipital bone and the transverse process of the atlas. The ligament was found on 12 of 26 sides (46.2%). The mean length of the ligament was 32.0 ± 5.5 mm. The ligament became taut with contralateral lateral flexion and the ipsilateral rotation of the atlantooccipital joint. We propose that this ligament may be termed the lateral oblique atlantooccipital ligament. To date, this structure has not been described in any textbooks or reports in the extant medical literature. Although its function is not clear, based on its course and connections, it might function as a secondary stabilizer of the atlantooccipital joint. As the stability of the craniocervical junction is of paramount importance, knowledge of normal and variant anatomical structures in this region is important for the surgeon treating patients with pathology of this region. These slides can be retrieved under Electronic Supplementary Material.
