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Avneesh Chhabra - One of the best experts on this subject based on the ideXlab platform.
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magnetic resonance neurography of the Lumbosacral Plexus in failed back surgery syndrome
Spine, 2017Co-Authors: Mohammed A Khaleel, Riham Dessouky, Dalia N Khalifa, Hazim I Tantawy, Avneesh ChhabraAbstract:Study Design.Retrospective clinical case series.Objective.To study the role of magnetic resonance neurography (MRN) of the Lumbosacral Plexus in management of patients with failed back surgery syndrome (FBSS).Summary of Background Data.FBSS is one of the major problems in health care, affecting up t
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3d mr neurography of the Lumbosacral Plexus obtaining optimal images for selective longitudinal nerve depiction
American Journal of Neuroradiology, 2016Co-Authors: Cho G Sims, Ethan Boothe, R Joodi, Avneesh ChhabraAbstract:BACKGROUND AND PURPOSE: The number of centers currently performing 3D fat-suppressed isotropic imaging is limited. If the angular orientations of the major Lumbosacral Plexus nerves on 3D isotropic MR neurography could be determined, similar planes could be prescribed during acquisition of 2D or 3D nonisotropic techniques for optimal depiction of various nerves. Our aim was to determine oblique sagittal and coronal angular measurements for longitudinal depiction of Lumbosacral Plexus nerves. Interobserver and intraobserver performance and mean calibers of sciatic and femoral nerves were also determined. MATERIALS AND METHODS: A consecutive series of Lumbosacral Plexus MR neurography examinations with 3D nerve-selective imaging performed during a 10-month period on a 3T scanner were evaluated. Two observers performed reconstructions and angular measurements. Sciatic and femoral nerve diameters were measured. Descriptive statistics and intraclass correlation coefficient correlations were used. RESULTS: There were 52 subjects, 11 men and 41 women. Mean sagittal thecal sac angles for coronal demonstration of Lumbosacral Plexus nerve roots from L1 to S1 for 2 independent observers measured 13.58° ± 2.87° and 13.61° ± 2.18°. Mean sagittal femoral nerve angles were 27.78° ± 4.81° and 28.94° ± 4.49°, and mean sagittal sciatic nerve angles were −10.7° ± 3.75° and −11.82° ± 2.87°. Coronal angular measurements of the femoral and sciatic nerves were similar. The intraclass correlation coefficient was moderate (0.582–0.671) for interobserver performance. For intraobserver performance among various angular measurements, the intraclass correlation coefficient was moderate to good (0.586–0.788). Femoral nerve caliber on MR imaging was almost half that of the sciatic nerve. Mean right femoral nerve thickness was 4.52 ± 1.11 mm and 4.85 ± 0.64 mm for the 2 observers, and mean left femoral nerve thickness was 4.48 ± 0.97 mm and 4.94 ± 0.57 mm. Mean right sciatic nerve thickness was 9.71 ± 1.76 mm and 9.94 ± 0.83 mm, and mean left sciatic nerve thickness was 10.03 ± 1.71 mm and 9.98 ± 0.99 mm. CONCLUSIONS: Angular Lumbosacral Plexus measurements aid in the prescription of different planes on MR imaging for the optimal longitudinal demonstration of nerves.
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incremental value of magnetic resonance neurography of Lumbosacral Plexus over non contributory lumbar spine magnetic resonance imaging in radiculopathy a prospective study
World Journal of Radiology, 2016Co-Authors: Avneesh Chhabra, Sahar J Farahani, Gaurav K Thawait, Vibhor Wadhwa, Allan J Belzberg, John A CarrinoAbstract:Incremental value of magnetic resonance neurography of Lumbosacral Plexus over non-contributory lumbar spine magnetic resonance imaging in radiculopathy: A prospective study
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high resolution 3 t mr neurography of the Lumbosacral Plexus
Radiographics, 2013Co-Authors: Theodoros Soldatos, Gaurav K Thawait, John A Carrino, Roman Guggenberger, Gustav Andreisek, Eric H Williams, Avneesh ChhabraAbstract:The Lumbosacral Plexus comprises a network of nerves that provide motor and sensory innervation to most structures of the pelvis and lower extremities. It is susceptible to various traumatic, inflammatory, metabolic, and neoplastic processes that may lead to lumbrosacral plexopathy, a serious and often disabling condition whose course and prognosis largely depend on the identification and cure of the causative condition. Whereas diagnosis of lumbrosacral plexopathy has traditionally relied on patients' medical history, clinical examination, and electrodiagnostic tests, magnetic resonance (MR) neurography plays an increasingly prominent role in noninvasive characterization of the type, location, and extent of lumbrosacral Plexus involvement and is developing into a useful diagnostic tool that substantially affects disease management. With use of 3-T MR imagers, improved coils, and advanced imaging sequences, which provide exquisite spatial resolution and soft-tissue contrast, MR neurography provides excellent depiction of the lumbrosacral Plexus and its peripheral branches and may be used to confirm a diagnosis of lumbrosacral plexopathy with high accuracy or provide superior anatomic information should surgical intervention be necessary.
Allan D Levi - One of the best experts on this subject based on the ideXlab platform.
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an anatomical study of the Lumbosacral Plexus as related to the minimally invasive transpsoas approach to the lumbar spine
Journal of Neurosurgery, 2009Co-Authors: Davi D M Benglis, Steve Vanni, Allan D LeviAbstract:OBJECT: Minimally invasive anterolateral approaches to the lumbar spine are options for the treatment of a number of adult degenerative spinal disorders. Nerve injuries during these surgeries, although rare, can be devastating complications. With an increasing number of spine surgeons utilizing minimal access retroperitoneal surgery to treat lumbar problems, the frequency of complications associated with this approach will likely increase. The authors sought to better understand the location of the lumbar contribution of the Lumbosacral Plexus relative to the disc spaces encountered when performing the minimally invasive transpsoas approach, also known as extreme lateral interbody fusion or direct lateral interbody fusion. METHODS: Three fresh cadavers were placed lateral, and a total of 3 dissections of the lumbar contribution of the Lumbosacral Plexus were performed. Radiopaque soldering wire was then laid along the anterior margin of the nerve fibers and the exiting femoral nerve. Markers were placed at the disc spaces and lateral fluoroscopy was used to measure the location of the lumbar Plexus along each respective disc space in the lumbar spine (L1-2, L2-3, L3-4, and L4-5). RESULTS: The Lumbosacral Plexus was found lying within the substance of the psoas muscle between the junction of the transverse process and vertebral body and exited along the medial edge of the psoas distally. The Lumbosacral Plexus was most dorsally positioned at the posterior endplate of L1-2. A general trend of progressive ventral migration of the Plexus on the disc space was noted at L2-3, L3-4, and L4-5. Average ratios were calculated at each level (location of the Plexus from the dorsal endplate to total disc length) and were 0 (L1-2), 0.11 (L2-3), 0.18 (L3-4), and 0.28 (L4-5). CONCLUSIONS: This anatomical study suggests that positioning the dilator and/or retractor in a posterior position of the disc space may result in nerve injury to the Lumbosacral Plexus, especially at the L4-5 level. The risk of injuring inherent nerve branches directed to the psoas muscle as well as injury to the genitofemoral nerve do still exist.
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an anatomical study of the Lumbosacral Plexus as related to the minimally invasive transpsoas approach to the lumbar spine
Journal of Neurosurgery, 2009Co-Authors: Davi D M Benglis, Steve Vanni, Allan D LeviAbstract:Object Minimally invasive anterolateral approaches to the lumbar spine are options for the treatment of a number of adult degenerative spinal disorders. Nerve injuries during these surgeries, although rare, can be devastating complications. With an increasing number of spine surgeons utilizing minimal access retroperitoneal surgery to treat lumbar problems, the frequency of complications associated with this approach will likely increase. The authors sought to better understand the location of the lumbar contribution of the Lumbosacral Plexus relative to the disc spaces encountered when performing the minimally invasive transpsoas approach, also known as extreme lateral interbody fusion or direct lateral interbody fusion. Methods Three fresh cadavers were placed lateral, and a total of 3 dissections of the lumbar contribution of the Lumbosacral Plexus were performed. Radiopaque soldering wire was then laid along the anterior margin of the nerve fibers and the exiting femoral nerve. Markers were placed at ...
Maria Siemionow - One of the best experts on this subject based on the ideXlab platform.
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anatomic variations of brachial and Lumbosacral Plexus models in different rat strains
Microsurgery, 2017Co-Authors: Adam Bobkiewicz, Joanna Cwykiel, Maria SiemionowAbstract:Purpose Selection of an appropriate model for preclinical assessment of new methods of peripheral nerve injury management is crucial. This report presents anatomic variations within brachial and Lumbosacral Plexuses in three selected rat strains Sprague Dawley (Hsd:Sprague Dawley SD), Lewis (LEW/SsNHsd), and Athymic Nude (Hsd:RH-Foxn1rnu) rats. Methods Based on their strain eighteen rats were divided into three groups. A total of 90 brachial Plexus nerves (axillary, musculocutaneous, median, ulnar, and radial nerves) and 72 Lumbosacral Plexus nerves (sciatic, tibial, common peroneal, and sural nerves) were analyzed for the length, diameter and correlation with the body weight. A detailed anatomic course of each nerve within the brachial and Lumbosacral Plexuses was outlined. Results The sural nerve was the longest nerve in all studied rat strains, whereas the sciatic nerve had the largest diameter. Comparison of all the nerves' length demonstrated that the Lewis rat sciatic and sural nerves were significantly shorter (P < 0.05). No significant differences in nerve diameters were found among the analyzed rat strain groups. Significant correlation was revealed between the length of sciatic nerve and the rats' weight, which is irrelevant to the rats' genetic background. Conclusions This study confirmed that nerves' length within rat's brachial and Lumbosacral Plexus depends on the inter-individual variations within the rat strains rather than on the differences in the peripheral nerve development, which is inherent to the specific rat strain. Correlation between the nerve length and body weight, suggests that bigger rats should be considered for studies requiring access to the long nerves. © 2016 Wiley Periodicals, Inc. Microsurgery, 2016.
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Anatomic variations of brachial and Lumbosacral Plexus models in different rat strains.
Microsurgery, 2016Co-Authors: Adam Bobkiewicz, Joanna Cwykiel, Maria SiemionowAbstract:Purpose Selection of an appropriate model for preclinical assessment of new methods of peripheral nerve injury management is crucial. This report presents anatomic variations within brachial and Lumbosacral Plexuses in three selected rat strains Sprague Dawley (Hsd:Sprague Dawley SD), Lewis (LEW/SsNHsd), and Athymic Nude (Hsd:RH-Foxn1rnu) rats. Methods Based on their strain eighteen rats were divided into three groups. A total of 90 brachial Plexus nerves (axillary, musculocutaneous, median, ulnar, and radial nerves) and 72 Lumbosacral Plexus nerves (sciatic, tibial, common peroneal, and sural nerves) were analyzed for the length, diameter and correlation with the body weight. A detailed anatomic course of each nerve within the brachial and Lumbosacral Plexuses was outlined. Results The sural nerve was the longest nerve in all studied rat strains, whereas the sciatic nerve had the largest diameter. Comparison of all the nerves' length demonstrated that the Lewis rat sciatic and sural nerves were significantly shorter (P
Davi D M Benglis - One of the best experts on this subject based on the ideXlab platform.
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an anatomical study of the Lumbosacral Plexus as related to the minimally invasive transpsoas approach to the lumbar spine
Journal of Neurosurgery, 2009Co-Authors: Davi D M Benglis, Steve Vanni, Allan D LeviAbstract:OBJECT: Minimally invasive anterolateral approaches to the lumbar spine are options for the treatment of a number of adult degenerative spinal disorders. Nerve injuries during these surgeries, although rare, can be devastating complications. With an increasing number of spine surgeons utilizing minimal access retroperitoneal surgery to treat lumbar problems, the frequency of complications associated with this approach will likely increase. The authors sought to better understand the location of the lumbar contribution of the Lumbosacral Plexus relative to the disc spaces encountered when performing the minimally invasive transpsoas approach, also known as extreme lateral interbody fusion or direct lateral interbody fusion. METHODS: Three fresh cadavers were placed lateral, and a total of 3 dissections of the lumbar contribution of the Lumbosacral Plexus were performed. Radiopaque soldering wire was then laid along the anterior margin of the nerve fibers and the exiting femoral nerve. Markers were placed at the disc spaces and lateral fluoroscopy was used to measure the location of the lumbar Plexus along each respective disc space in the lumbar spine (L1-2, L2-3, L3-4, and L4-5). RESULTS: The Lumbosacral Plexus was found lying within the substance of the psoas muscle between the junction of the transverse process and vertebral body and exited along the medial edge of the psoas distally. The Lumbosacral Plexus was most dorsally positioned at the posterior endplate of L1-2. A general trend of progressive ventral migration of the Plexus on the disc space was noted at L2-3, L3-4, and L4-5. Average ratios were calculated at each level (location of the Plexus from the dorsal endplate to total disc length) and were 0 (L1-2), 0.11 (L2-3), 0.18 (L3-4), and 0.28 (L4-5). CONCLUSIONS: This anatomical study suggests that positioning the dilator and/or retractor in a posterior position of the disc space may result in nerve injury to the Lumbosacral Plexus, especially at the L4-5 level. The risk of injuring inherent nerve branches directed to the psoas muscle as well as injury to the genitofemoral nerve do still exist.
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an anatomical study of the Lumbosacral Plexus as related to the minimally invasive transpsoas approach to the lumbar spine
Journal of Neurosurgery, 2009Co-Authors: Davi D M Benglis, Steve Vanni, Allan D LeviAbstract:Object Minimally invasive anterolateral approaches to the lumbar spine are options for the treatment of a number of adult degenerative spinal disorders. Nerve injuries during these surgeries, although rare, can be devastating complications. With an increasing number of spine surgeons utilizing minimal access retroperitoneal surgery to treat lumbar problems, the frequency of complications associated with this approach will likely increase. The authors sought to better understand the location of the lumbar contribution of the Lumbosacral Plexus relative to the disc spaces encountered when performing the minimally invasive transpsoas approach, also known as extreme lateral interbody fusion or direct lateral interbody fusion. Methods Three fresh cadavers were placed lateral, and a total of 3 dissections of the lumbar contribution of the Lumbosacral Plexus were performed. Radiopaque soldering wire was then laid along the anterior margin of the nerve fibers and the exiting femoral nerve. Markers were placed at ...
Aimin Chen - One of the best experts on this subject based on the ideXlab platform.
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unaffected contralateral s1 transfer for the treatment of Lumbosacral Plexus avulsion
Injury-international Journal of The Care of The Injured, 2014Co-Authors: Yongchuan Li, Liangyu Zhao, Aimin ChenAbstract:Abstract Introduction This study describes a new surgical strategy for Lumbosacral Plexus avulsion by transfer of the unaffected contralateral S1 nerve root. Methods A surgical reconstruction of the sacral nerve was performed on a 10-year-old boy with left Lumbosacral Plexus avulsion. The unaffected S1 nerve root (right side) is severed extradurally for transfer. A 25-cm long nerve graft from the common peroneal nerve of the affected side was used as donor nerve. One end of the nerve graft was anastomosed to the proximal stump of the right-sided extradural S1 nerve. The distal end of the nerve graft was divided into two fascicles and anastomosed to the left-sided inferior gluteal nerve and the branch of the sciatic nerve innervating the left-sided hamstrings. Results According to motor score of the British Medical Research Council (MRC) system, the strength of glutei and hamstrings improved to the level of M3 1.5 years after surgery. Conclusions The extradural S1 nerve root in the unaffected side can be considered as a suitable donor nerve for transfer in patients with root avulsion of the lumbar or sacral nerve Plexus.
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contralateral l 6 nerve root transfer to repair Lumbosacral Plexus root avulsion experimental study in rhesus monkeys
Journal of Neurosurgery, 2013Co-Authors: Aimin ChenAbstract:Object Nerve transfer is used for brachial Plexus injuries but has rarely been applied to repairs in the lower extremities. The aim of this study was to evaluate the feasibility and effectiveness of using the contralateral L-6 nerve root to repair Lumbosacral Plexus root avulsions. Methods Eighteen rhesus monkeys were randomized into 3 groups. In the experimental group, the left L4–7 and S-1 nerve roots were avulsed and the right L-6 nerve root was transferred to the left inferior gluteal nerve and the sciatic nerve branch innervating the hamstrings. In the control group, the left L4–7 and S-1 nerve roots were avulsed and nerve transfer was not performed. In the sham operation group, the animals underwent a procedure that did not involve nerve avulsion and nerve transfer. Functional outcomes were measured by electrophysiological study, muscle mass investigation, and histological study. Results The mean amplitudes of the compound muscle action potentials from the gluteus maximus and biceps femoris in the e...
