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Ossama Al-mefty - One of the best experts on this subject based on the ideXlab platform.
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Anatomy of the Nuchal Ligament and its surgical applications.
Neurosurgery, 2007Co-Authors: Paulo A. S. Kadri, Ossama Al-meftyAbstract:OBJECTIVE: Although considered a basic maneuver for neurosurgical procedures, dissection of the musculature of the posterior cervical spine can be a source of complications during surgery. These complications include excessive blood loss, a loss of the plane of dissection, and injury to important structures such as the vertebral artery and nerve roots. Inappropriate closing of the muscular plane might also contribute to leakage of spinal fluid and postoperative deformation of the cervical spine. We review the anatomy of the Nuchal Ligament and describe a technical nuance based on the characteristics of the Ligament's components, which can be used to assure the midline for a bloodless and atraumatic dissection. METHODS: We set out to determine whether or not the Nuchal Ligament could be used as a natural plane of dissection for splitting the posterior cervical musculature. We studied the anatomy of the Nuchal Ligament in five cadavers. RESULTS: The Nuchal Ligament extends from the external occipital protuberance to the spinous process of the seventh cervical vertebra (C7). It is covered by layers of cervical fascia and the aponeurosis of the trapezius muscle. It is composed of two portions: 1) the lamellar portion, an anterior double-layered portion with fatty areolar tissue interposed between its layers that inserts into the medial side of the bifid spinous process of the cervical vertebra; and 2) the funicular portion, a posterior fibrous portion that corresponds to the fusion of the layers of the lamellar portion. CONCLUSION: Several steps can assure that the midline plane is respected, thereby decreasing risk and reducing trauma and blood loss during dissection: 1) dissection of the Nuchal Ligament within the fatty areolar tissue of the lamellar portion, 2) isolation and incision of the funicular portion from inside to outside, and 3) retrograde dissection of the cervicoNuchal muscles attached to the occipital bone in a subperiosteal plane.
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Anatomy of the Nuchal Ligament and its surgical applications.
Neurosurgery, 2007Co-Authors: Paulo A. S. Kadri, Ossama Al-meftyAbstract:Although considered a basic maneuver for neurosurgical procedures, dissection of the musculature of the posterior cervical spine can be a source of complications during surgery. These complications include excessive blood loss, a loss of the plane of dissection, and injury to important structures such as the vertebral artery and nerve roots. Inappropriate closing of the muscular plane might also contribute to leakage of spinal fluid and postoperative deformation of the cervical spine. We review the anatomy of the Nuchal Ligament and describe a technical nuance based on the characteristics of the Ligament's components, which can be used to assure the midline for a bloodless and atraumatic dissection. We set out to determine whether or not the Nuchal Ligament could be used as a natural plane of dissection for splitting the posterior cervical musculature. We studied the anatomy of the Nuchal Ligament in five cadavers. The Nuchal Ligament extends from the external occipital protuberance to the spinous process of the seventh cervical vertebra (C7). It is covered by layers of cervical fascia and the aponeurosis of the trapezius muscle. It is composed of two portions: 1) the lamellar portion, an anterior double-layered portion with fatty areolar tissue interposed between its layers that inserts into the medial side of the bifid spinous process of the cervical vertebra; and 2) the funicular portion, a posterior fibrous portion that corresponds to the fusion of the layers of the lamellar portion. Several steps can assure that the midline plane is respected, thereby decreasing risk and reducing trauma and blood loss during dissection: 1) dissection of the Nuchal Ligament within the fatty areolar tissue of the lamellar portion, 2) isolation and incision of the funicular portion from inside to outside, and 3) retrograde dissection of the cervicoNuchal muscles attached to the occipital bone in a subperiosteal plane.
J K Belknap - One of the best experts on this subject based on the ideXlab platform.
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proinflammatory cytokine and chemokine gene expression profiles in subcutaneous and visceral adipose tissue depots of insulin resistant and insulin sensitive light breed horses
Journal of Veterinary Internal Medicine, 2010Co-Authors: T A Burns, R J Geor, Margaret C Mudge, L J Mccutcheon, K W Hinchcliff, J K BelknapAbstract:Background: Insulin resistance has been associated with risk of laminitis in horses. Genes coding for proinflammatory cytokines and chemokines are expressed more in visceral adipose tissue than in subcutaneous adipose tissue of insulin-resistant (IR) humans and rodents. Hypothesis/Objectives: To investigate adipose depot-specific cytokine and chemokine gene expression in horses and its relationship to insulin sensitivity (SI). Animals: Eleven light breed mares. Methods: Animals were classified as IR (SI = 0.58 ± 0.31 × 10−4 L/min/mU; n = 5) or insulin sensitive (IS; SI = 2.59 ± 1.21 × 10−4 L/min/mU; n = 6) based on results of a frequently sampled intravenous glucose tolerance test. Omental, retroperitoneal, and mesocolonic fat was collected by ventral midline celiotomy; incisional Nuchal Ligament and tail head adipose tissue biopsy specimens were collected concurrently. The expression of tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, IL-6, plasminogen activator inhibitor-1 (PAI-1), and monocyte chemoattractant protein-1 (MCP-1) in each depot was measured by real-time quantitative polymerase chain reaction. Data were analyzed by 2-way analysis of variance for repeated measures (P < .05). Results: No differences in TNF-α, IL-1β, IL-6, PAI-1, or MCP-1 mRNA concentrations were noted between IR and IS groups for each depot. Concentrations of mRNA coding for IL-1β (P= .0005) and IL-6 (P= .004) were significantly higher in Nuchal Ligament adipose tissue than in other depots. Conclusions and Clinical Importance: These data suggest that the Nuchal Ligament depot has unique biological behavior in the horse and is more likely to adopt an inflammatory phenotype than other depots examined. Visceral fat may not contribute to the pathogenesis of obesity-related disorders in the horse as in other species.
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Proinflammatory Cytokine and Chemokine Gene Expression Profiles in Subcutaneous and Visceral Adipose Tissue Depots of Insulin‐Resistant and Insulin‐Sensitive Light Breed Horses
Journal of veterinary internal medicine, 2010Co-Authors: T A Burns, R J Geor, Margaret C Mudge, L J Mccutcheon, K W Hinchcliff, J K BelknapAbstract:Background: Insulin resistance has been associated with risk of laminitis in horses. Genes coding for proinflammatory cytokines and chemokines are expressed more in visceral adipose tissue than in subcutaneous adipose tissue of insulin-resistant (IR) humans and rodents. Hypothesis/Objectives: To investigate adipose depot-specific cytokine and chemokine gene expression in horses and its relationship to insulin sensitivity (SI). Animals: Eleven light breed mares. Methods: Animals were classified as IR (SI = 0.58 ± 0.31 × 10−4 L/min/mU; n = 5) or insulin sensitive (IS; SI = 2.59 ± 1.21 × 10−4 L/min/mU; n = 6) based on results of a frequently sampled intravenous glucose tolerance test. Omental, retroperitoneal, and mesocolonic fat was collected by ventral midline celiotomy; incisional Nuchal Ligament and tail head adipose tissue biopsy specimens were collected concurrently. The expression of tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, IL-6, plasminogen activator inhibitor-1 (PAI-1), and monocyte chemoattractant protein-1 (MCP-1) in each depot was measured by real-time quantitative polymerase chain reaction. Data were analyzed by 2-way analysis of variance for repeated measures (P < .05). Results: No differences in TNF-α, IL-1β, IL-6, PAI-1, or MCP-1 mRNA concentrations were noted between IR and IS groups for each depot. Concentrations of mRNA coding for IL-1β (P= .0005) and IL-6 (P= .004) were significantly higher in Nuchal Ligament adipose tissue than in other depots. Conclusions and Clinical Importance: These data suggest that the Nuchal Ligament depot has unique biological behavior in the horse and is more likely to adopt an inflammatory phenotype than other depots examined. Visceral fat may not contribute to the pathogenesis of obesity-related disorders in the horse as in other species.
Kozo Nakamura - One of the best experts on this subject based on the ideXlab platform.
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the Nuchal Ligament restrains cervical spine flexion
Spine, 2004Co-Authors: Katsushi Takeshita, Erik T K Peterson, Donita I Bylskiaustrow, Alvin H Crawford, Kozo NakamuraAbstract:STUDY DESIGN A biomechanical study using a cadaver model was conducted to define the function of the Nuchal Ligament in the restraint of flexion of the cervical spine. OBJECTIVE To test the hypothesis that surgical resection of the Nuchal Ligament significantly reduces the structural restraints to cervical flexion. SUMMARY OF BACKGROUND DATA Although previous studies have examined the role of the posterior Ligaments and capsules on cervical stability, no prior study has quantified the biomechanical significance of the Nuchal Ligament. The clinical significance may include progressive loss of lordosis or even kyphosis after trauma or posterior surgical procedures such as laminectomy, laminoplasty, or tumor resection. METHODS Cervical spines from the occiput to the first thoracic vertebra were harvested from 12 human cadavers. Specimens were tested under 3 conditions: all Ligaments intact, after resection of the Nuchal Ligament, and then after additional resection of the supraspinous, interspinous, and yellow Ligaments. Flexion moments were applied; load and displacement were measured. Changes in flexion range of motion and tangent stiffness between treatment conditions were statistically compared. RESULTS The flexion range increased 28% after removing the Nuchal Ligament. After subsequent resections, the flexion range increased 52% compared with intact (P <0.005). Tangent stiffness decreased 27% after Nuchal Ligament resection; after all resections, stiffness was 35% lower than intact (P <0.05). CONCLUSION Resection of the Nuchal Ligament increased the flexion range of motion and decreased stiffness in flexion. Injury to the Nuchal Ligament may increase the risk of cervical spine instability and malalignment.
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The Nuchal Ligament restrains cervical spine flexion.
Spine, 2004Co-Authors: Katsushi Takeshita, Erik T K Peterson, Alvin H Crawford, Donita I. Bylski-austrow, Kozo NakamuraAbstract:STUDY DESIGN A biomechanical study using a cadaver model was conducted to define the function of the Nuchal Ligament in the restraint of flexion of the cervical spine. OBJECTIVE To test the hypothesis that surgical resection of the Nuchal Ligament significantly reduces the structural restraints to cervical flexion. SUMMARY OF BACKGROUND DATA Although previous studies have examined the role of the posterior Ligaments and capsules on cervical stability, no prior study has quantified the biomechanical significance of the Nuchal Ligament. The clinical significance may include progressive loss of lordosis or even kyphosis after trauma or posterior surgical procedures such as laminectomy, laminoplasty, or tumor resection. METHODS Cervical spines from the occiput to the first thoracic vertebra were harvested from 12 human cadavers. Specimens were tested under 3 conditions: all Ligaments intact, after resection of the Nuchal Ligament, and then after additional resection of the supraspinous, interspinous, and yellow Ligaments. Flexion moments were applied; load and displacement were measured. Changes in flexion range of motion and tangent stiffness between treatment conditions were statistically compared. RESULTS The flexion range increased 28% after removing the Nuchal Ligament. After subsequent resections, the flexion range increased 52% compared with intact (P
Paulo A. S. Kadri - One of the best experts on this subject based on the ideXlab platform.
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Anatomy of the Nuchal Ligament and its surgical applications.
Neurosurgery, 2007Co-Authors: Paulo A. S. Kadri, Ossama Al-meftyAbstract:OBJECTIVE: Although considered a basic maneuver for neurosurgical procedures, dissection of the musculature of the posterior cervical spine can be a source of complications during surgery. These complications include excessive blood loss, a loss of the plane of dissection, and injury to important structures such as the vertebral artery and nerve roots. Inappropriate closing of the muscular plane might also contribute to leakage of spinal fluid and postoperative deformation of the cervical spine. We review the anatomy of the Nuchal Ligament and describe a technical nuance based on the characteristics of the Ligament's components, which can be used to assure the midline for a bloodless and atraumatic dissection. METHODS: We set out to determine whether or not the Nuchal Ligament could be used as a natural plane of dissection for splitting the posterior cervical musculature. We studied the anatomy of the Nuchal Ligament in five cadavers. RESULTS: The Nuchal Ligament extends from the external occipital protuberance to the spinous process of the seventh cervical vertebra (C7). It is covered by layers of cervical fascia and the aponeurosis of the trapezius muscle. It is composed of two portions: 1) the lamellar portion, an anterior double-layered portion with fatty areolar tissue interposed between its layers that inserts into the medial side of the bifid spinous process of the cervical vertebra; and 2) the funicular portion, a posterior fibrous portion that corresponds to the fusion of the layers of the lamellar portion. CONCLUSION: Several steps can assure that the midline plane is respected, thereby decreasing risk and reducing trauma and blood loss during dissection: 1) dissection of the Nuchal Ligament within the fatty areolar tissue of the lamellar portion, 2) isolation and incision of the funicular portion from inside to outside, and 3) retrograde dissection of the cervicoNuchal muscles attached to the occipital bone in a subperiosteal plane.
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Anatomy of the Nuchal Ligament and its surgical applications.
Neurosurgery, 2007Co-Authors: Paulo A. S. Kadri, Ossama Al-meftyAbstract:Although considered a basic maneuver for neurosurgical procedures, dissection of the musculature of the posterior cervical spine can be a source of complications during surgery. These complications include excessive blood loss, a loss of the plane of dissection, and injury to important structures such as the vertebral artery and nerve roots. Inappropriate closing of the muscular plane might also contribute to leakage of spinal fluid and postoperative deformation of the cervical spine. We review the anatomy of the Nuchal Ligament and describe a technical nuance based on the characteristics of the Ligament's components, which can be used to assure the midline for a bloodless and atraumatic dissection. We set out to determine whether or not the Nuchal Ligament could be used as a natural plane of dissection for splitting the posterior cervical musculature. We studied the anatomy of the Nuchal Ligament in five cadavers. The Nuchal Ligament extends from the external occipital protuberance to the spinous process of the seventh cervical vertebra (C7). It is covered by layers of cervical fascia and the aponeurosis of the trapezius muscle. It is composed of two portions: 1) the lamellar portion, an anterior double-layered portion with fatty areolar tissue interposed between its layers that inserts into the medial side of the bifid spinous process of the cervical vertebra; and 2) the funicular portion, a posterior fibrous portion that corresponds to the fusion of the layers of the lamellar portion. Several steps can assure that the midline plane is respected, thereby decreasing risk and reducing trauma and blood loss during dissection: 1) dissection of the Nuchal Ligament within the fatty areolar tissue of the lamellar portion, 2) isolation and incision of the funicular portion from inside to outside, and 3) retrograde dissection of the cervicoNuchal muscles attached to the occipital bone in a subperiosteal plane.
Mecit Kantarci - One of the best experts on this subject based on the ideXlab platform.
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a sesamoid ossicle of the Nuchal Ligament mimicking spinous avulsion fracture
The Spine Journal, 2016Co-Authors: Ihsan Yuce, Berhan Pirimoglu, Gokhan Polat, Recep Sade, Mucahit Emet, Mecit KantarciAbstract:A 25-year-old man who suffered a traffic accident was admitted to our emergency department. Computer tomography was performed. Computer tomography images showed an osseous structure mimicking avulsion fracture at the level of C5–C6 (Fig. 1). There was no bone defect corresponding to spinous process and so, the diagnosis was consistent with sesamoid ossicles of the Nuchal Ligament. Sesamoid ossicles of the Nuchal Ligament are an anatomical variant that are usually asymptomatic. Prominent differential diagnosis includes avulsion fractures of the spinal processes and myositis ossificans. Focal well-defined osseous masses, well-circumscribed with regular shape, are in favor of sesamoid ossicle of Nuchal Ligament, whereas triangular dense bony fragment with bony defect of the adjacent spinous process are in favor of spinous process fracture. Ihsan Yuce, MD Berhan Pirimoglu, MD Gokhan Polat, MD Recep Sade, MD Mucahit Emet, MD Mecit Kantarci, MD, PhD Department of Radiology, School of Medicine Ataturk University 25100 Erzurum, Turkey Department of Emergency Medicine, School of Medicine Ataturk University 25100 Erzurum, Turkey
