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Sample records for lumbar apophyseal ring

  1. Persistent tight hamstrings following conservative treatment for apophyseal ring fracture in adolescent athletes: critical appraisal.

    PubMed

    Miyagi, Ryo; Sairyo, Koichi; Sakai, Toshinori; Tezuka, Fumitake; Kitagawa, Yasuhiro; Dezawa, Akira

    2014-01-01

    Apophyseal ring fracture is a unique disease in children and adolescents. Its clinical features include low back pain, sciatica, paravertebral muscle spasm and tenderness, restricted back motion, neurological symptoms, and tight hamstrings. For all athletes, body flexibility is one of the most important factors for better performance. Therefore, persistent tight hamstrings has a negative influence on athletic performance. In this report, we present two adolescent athletes with apophyseal ring fracture treated successfully by conservative treatment for severe low back pain (LBP) and leg pain, despite having persistent tight hamstrings for more than one year. Unlike herniated nucleus pulposus, bony fragments in the spinal canal never disappear. Although conservative treatment can alleviate LBP and leg pain, surgical removal of fragments is considered when symptoms such as tight hamstrings and restricted lumbar motion due to canal stenosis are found, particularly in athletes. PMID:25264071

  2. Apophyseal ring fracture associated with two levels extruded disc herniation: case report and review of the literature

    PubMed Central

    da Silva Alvarenga, José Alexandre Lopes; Ueta, Fernando Tadashi Salvioni; Curto, David Del; Ueta, Renato Hiroshi Salvioni; Martins, Delio Eulalio; Wajchenberg, Marcelo; Puertas, Eduardo Barros

    2014-01-01

    ABSTRACT Apophyseal ring fractures are rare injuries that may be associated with lumbar disc herniation in young patients. We report a unique case in the literature of a 15-year-old male patient who played football and was admitted at our service complaining of sciatica radiating into the left leg. An apophysial ring injury of L5 vertebral body was observed. This injury caused two extruded disc herniation in adjacent levels. Surgical procedure was indicated after failure of conservative treatment. PMID:25003931

  3. A posterior ring apophyseal fracture and disc herniation in a 21-year-old competitive basketball player: a case report

    PubMed Central

    Deleo, Trevor; Merotto, Samuel; Smith, Colyn; D’Angelo, Kevin

    2015-01-01

    Objective: To describe the diagnosis and management of a competitive male basketball player with discogenic low back pain and presence of an old posterior ring apophyseal fracture (PRAF). This case will highlight the importance of early recognition and considerations regarding patient management for this differential of radiating low back pain. Clinical Features: A 21-year-old provincial basketball player presented with recurrent radiating low back pain into the left groin and lower limb. After several weeks of persistent symptoms including pain, muscle weakness, and changes in the Achilles deep tendon reflex, imaging was obtained that revealed a large disc extrusion with an old posterior ring apophyseal fracture. In collaboration with a spine surgeon and family physician, the patient was treated using a conservative, multimodal approach. Treatment consisted of graded mobilizations, spinal manipulative therapy, interferential current, and soft tissue therapy to the lumbar spine. Rehabilitation exercises focused on centralizing symptoms and improving strength, proprioception and function of the lower limb. After a period of 8 weeks, the patient was able to complete all activities of daily living without pain in addition to returning to basketball practice. Summary: PRAF is a unique condition in the immature spine and recent evidence suggests that those involved in sports requiring repetitive motion of the lumbar spine may be at increased risk. The astute clinician must consider this differential in young populations presenting with discogenic low back pain, as a timely diagnosis and necessary referral may allow for effective conservative management to reduce symptoms. Equally as important, one must be aware of the complications from PRAF as a contributing source of low back pain and dysfunction into adulthood. Knowing when to refer for advanced imaging and/or a surgical consult given the variable clinical presentation and prognosis is an essential component to care

  4. Lateral Lumbar Interbody Fusion

    PubMed Central

    Hughes, Alexander; Girardi, Federico; Sama, Andrew; Lebl, Darren; Cammisa, Frank

    2015-01-01

    The lateral lumbar interbody fusion (LLIF) is a relatively new technique that allows the surgeon to access the intervertebral space from a direct lateral approach either anterior to or through the psoas muscle. This approach provides an alternative to anterior lumbar interbody fusion with instrumentation, posterior lumbar interbody fusion, and transforaminal lumbar interbody fusion for anterior column support. LLIF is minimally invasive, safe, better structural support from the apophyseal ring, potential for coronal plane deformity correction, and indirect decompression, which have has made this technique popular. LLIF is currently being utilized for a variety of pathologies including but not limited to adult de novo lumbar scoliosis, central and foraminal stenosis, spondylolisthesis, and adjacent segment degeneration. Although early clinical outcomes have been good, the potential for significant neurological and vascular vertebral endplate complications exists. Nevertheless, LLIF is a promising technique with the potential to more effectively treat complex adult de novo scoliosis and achieve predictable fusion while avoiding the complications of traditional anterior surgery and posterior interbody techniques. PMID:26713134

  5. Lateral Lumbar Interbody Fusion.

    PubMed

    Pawar, Abhijit; Hughes, Alexander; Girardi, Federico; Sama, Andrew; Lebl, Darren; Cammisa, Frank

    2015-12-01

    The lateral lumbar interbody fusion (LLIF) is a relatively new technique that allows the surgeon to access the intervertebral space from a direct lateral approach either anterior to or through the psoas muscle. This approach provides an alternative to anterior lumbar interbody fusion with instrumentation, posterior lumbar interbody fusion, and transforaminal lumbar interbody fusion for anterior column support. LLIF is minimally invasive, safe, better structural support from the apophyseal ring, potential for coronal plane deformity correction, and indirect decompression, which have has made this technique popular. LLIF is currently being utilized for a variety of pathologies including but not limited to adult de novo lumbar scoliosis, central and foraminal stenosis, spondylolisthesis, and adjacent segment degeneration. Although early clinical outcomes have been good, the potential for significant neurological and vascular vertebral endplate complications exists. Nevertheless, LLIF is a promising technique with the potential to more effectively treat complex adult de novo scoliosis and achieve predictable fusion while avoiding the complications of traditional anterior surgery and posterior interbody techniques. PMID:26713134

  6. Greater trochanter apophysitis in the adolescent athlete.

    PubMed

    Young, Simon W; Safran, Marc R

    2015-05-01

    Lower limb traction apophysitis is common in young athletes, occurring at sites such as the tibial tubercle (Osgood-Schlatter disease) and distal patella (Sinding-Larsen-Johansson disease). Around the hip, iliac apophysitis is well recognized, but no cases of greater trochanter apophysitis have previously been reported. We describe the case of a 15-year-old male basketball player with a 2-month history of the right hip pain and significant functional limitation. X-rays revealed widening of the greater trochanter apophysis with subchondral sclerosis, consistent with a diagnosis of traction apophysitis. The patient was treated with a period of relative rest and anti-inflammatory medication. He gradually returned to full athletic activity, including basketball, without recurrence of pain or limitation. We describe the first reported case of traction apophysitis of the greater trochanter. The unique muscular anatomy of this apophysis with balanced forces explains the rarity of this condition. If encountered, rest and activity modification is the recommended treatment. PMID:24942622

  7. Bone Scintigraphy and CT Findings in Transverse Process Apophysitis.

    PubMed

    Dua, Sumeet G; Ali, Amjad

    2016-07-01

    A 14-year-old avid gymnast presented with recent onset of increasing lower thoracic back pain. Clinical examination revealed point tenderness at about T10 level. Focal uptake was seen to the left of the midline on a bone scan ordered to exclude stress fracture. Spine CT when read in conjunction with the bone scan revealed apophysitis of the transverse process. Apophysitis of the posterior elements of the vertebrae is a rare cause of back pain in adolescents. PMID:26914575

  8. APOPHYSEAL FRACTURE OR AVULSION OF THE GREATER TROCHANTER

    PubMed Central

    FREITAS, ANDERSON; MACEDO, SÍLVIO LEITE DE

    2016-01-01

    ABSTRACTS The apophyseal fracture or avulsion of the greater trochanter occurs in skeletally immature patients. It has at etiological factors indirect mechanisms (avulsion) and direct mechanisms (trauma on the trochanter), the latter being the most common. The clinical presentation is easily identified and a simple X- ray can confirm the diagnosis. Regardless of the treatment chosen, this pathology has a high correlation with osteonecrosis of the femoral head, even as a rare fact, however with innocent appearance, on this pathology. PMID:27217820

  9. Three-Dimensional Analysis of a Ballet Dancer with Ischial Tuberosity Apophysitis. A Case Study

    PubMed Central

    Pohjola, Hanna; Sayers, Mark; Mellifont, Rebecca; Mellifont, Daniel; Venojärvi, Mika

    2014-01-01

    The purpose of this case study was to describe the three-dimensional biomechanics of common ballet exercises in a ballet dancer with ischial tuberosity apophysitis. This was achieved by comparing kinematics between the symptomatic (i.e. ischial apophyseal symptoms) and contralateral lower limbs, as well as via reported pain. Results suggest consistent differences in movement patterns in this dancer. These differences included: 1) decreased external rotation of contralateral hip, hence a decreased hip contribution to ‘turn out’; 2) increased contralateral knee adduction and internal rotation; 3) an apparent synchronicity in the contralateral lower limb of the decreased hip external rotation and increased knee adduction; and 4) minimal use of ankle plantar/dorsiflexion movement for symptomatic side. Pain related to the left ischial apophysitis was associated with reduced amplitudes especially in fast ballet movements that required large range of motion in flexion and adduction in the left hip joint. These findings suggest that ischial apophysitis may limit dancer’s ballet technique and performance. Key Points The pain related to the left ischial apophysitis was associated with reduced amplitudes especially in fast ballet movements that require large range of motion. This may affect to the lower limbs kinematics, and limit dancer’s technique and performance. Compensatory strategies in the kinetic chain, differences in the joint angles between the lower limbs, traction forces, velocity and amplitude demands should be taken in consideration while training and rehabilitation of the ischial apophyseal injury within classical ballet. PMID:25435780

  10. Three-dimensional analysis of a ballet dancer with ischial tuberosity apophysitis. A case study.

    PubMed

    Pohjola, Hanna; Sayers, Mark; Mellifont, Rebecca; Mellifont, Daniel; Venojärvi, Mika

    2014-12-01

    The purpose of this case study was to describe the three-dimensional biomechanics of common ballet exercises in a ballet dancer with ischial tuberosity apophysitis. This was achieved by comparing kinematics between the symptomatic (i.e. ischial apophyseal symptoms) and contralateral lower limbs, as well as via reported pain. Results suggest consistent differences in movement patterns in this dancer. These differences included: 1) decreased external rotation of contralateral hip, hence a decreased hip contribution to 'turn out'; 2) increased contralateral knee adduction and internal rotation; 3) an apparent synchronicity in the contralateral lower limb of the decreased hip external rotation and increased knee adduction; and 4) minimal use of ankle plantar/dorsiflexion movement for symptomatic side. Pain related to the left ischial apophysitis was associated with reduced amplitudes especially in fast ballet movements that required large range of motion in flexion and adduction in the left hip joint. These findings suggest that ischial apophysitis may limit dancer's ballet technique and performance. Key PointsThe pain related to the left ischial apophysitis was associated with reduced amplitudes especially in fast ballet movements that require large range of motion. This may affect to the lower limbs kinematics, and limit dancer's technique and performance.Compensatory strategies in the kinetic chain, differences in the joint angles between the lower limbs, traction forces, velocity and amplitude demands should be taken in consideration while training and rehabilitation of the ischial apophyseal injury within classical ballet. PMID:25435780

  11. McKenzie treatment versus mulligan sustained natural apophyseal glides for chronic mechanical low back pain

    PubMed Central

    Waqqar, Saira; Shakil-ur-Rehman, Syed; Ahmad, Shakeel

    2016-01-01

    Background and Objective: Chronic mechanical low back pain is common among different age groups and genders. Different manual therapy techniques combined with exercise therapy and electrotherapy modalities play an important role in its management. Our objective was to compare the effects of McKenzie extension exercisesprogram (EEP) versus Mulligan Sustained Natural Apophyseal Glides (SNAGs) for chronic mechanical low back pain (CMLBP). Methods: This randomized control trial (RCT) was conducted at Riphah Physical Rehabilitation Centre, Pakistan Railways General Hospital Rawalpindi, from 1st July to 31st December 2014. The inclusion criteria was patients of both gender and age range 30-70 years with minimum 4 weeks history of CMLBP. A total of 37 patients were screened out as per inclusion criteria and randomly placed into two groups. Twenty patients in group A were treated with Mulligan SNAGs and 17 patients in group B with McKenzie EEP for four weeks at two session per week and single session per day. Visual Analogue Scale (VAS), Oswestry Disability Scale (ODI) and lumber Range of Motion (ROM) were used as an assessment tools and were measured at baseline and at the completion 4 weeks intervention. The data was analyzed with SPSS to draw the statistical and clinical significance of both interventions. Results: At the completion of 4 weeks intervention the pre and post statistical analysis revealed that clinically the McKenzie EEP improved pain (mean 9.12 to 1.46) and disability (73.82 to 6.24) slightly more than Mulligan SNAGs (pain: from 8.85 to 2.55, disability 73.75 to 7.05), while the Mulligan SNAGs improved lumbar ROM more effectively than McKenzie EEP in all directions including flexion, extension, side bending and rotation. Statistically there was no significant difference between the effects of two interventions in managing pain and disability, and improving Lumber ROM. Conclusion: McKenzie EEP is clinically slightly more effective in the management of pain

  12. Traction apophysitis of the fifth metatarsal base in a child: Iselin's disease

    PubMed Central

    Deniz, Gokmen; Kose, Ozkan; Guneri, Bulent; Duygun, Fatih

    2014-01-01

    Although Iselin's disease, apophysitis of the fifth metatarsal base, is not infrequent in clinical practice, it is accepted as a rare cause of lateral foot pain in young adolescents. Usually a simple clinical examination and radiographs are sufficient for diagnosis. We present a patient with Iselin's disease and discuss its clinical and radiographic characteristics, differential diagnosis, aetiopathogenesis and treatment. PMID:24832713

  13. Pubic apophysitis: a previously undescribed clinical entity of groin pain in athletes

    PubMed Central

    Sailly, Matthieu; Whiteley, Rod; Read, John W; Giuffre, Bruno; Johnson, Amanda; Hölmich, Per

    2015-01-01

    Background Sport-related pubalgia is often a diagnostic challenge in elite athletes. While scientific attention has focused on adults, there is little data on adolescents. Cadaveric and imaging studies identify a secondary ossification centre located along the anteromedial corner of pubis beneath the insertions of symphysial joint capsule and adductor longus tendon. Little is known about this apophysis and its response to chronic stress. Aim We report pubic apophysitis as a clinically relevant entity in adolescent athletes. Methods The clinical and imaging findings in 26 highly trained adolescent football players (15.6 years±1.3) who complained of adductor-related groin pain were reviewed. The imaging features (X-ray 26/26, US 9/26, MRI 11/26, CT 7/26) of the pubic apophyses in this symptomatic group were compared against those of a comparison group of 31 male patients (age range 9–30 years) with no known history of groin pain or pelvic trauma, who underwent pelvic CT scans for unrelated medical reasons. Results All symptomatic subjects presented with similar history and physical findings. The CT scans of these patients demonstrated open pubic apophyses with stress-related physeal changes (widening, asymmetry and small rounded cyst-like expansions) that were not observed in the comparison group. No comparison subject demonstrated apophyseal maturity before 21 years of age, and immaturity was seen up to the age of 26 years. Conclusions This retrospective case series identifies pubic apophyseal stress (or ‘apophysitis’) as an important differential consideration in the adolescent athlete who presents with groin pain. PMID:26031648

  14. Late presentation of a subiliacus haematoma after an apophyseal injury of the anterior inferior iliac spine

    PubMed Central

    Khan, Muhammad Asim; Whitaker, Samuel Richard; Ibrahim, Mazin S; Haddad, Fares S

    2014-01-01

    Apophyseal injuries are particularly common in adolescents when the growth spurt that accompanies puberty places increased strain on developing bones and muscles. Bone growth in particular exceeds that of soft tissues resulting in relatively tight musculature and subsequent excessive strain at these sites of tendon insertion into bone. We describe a case of a young athlete who presented with chronic hip pain after an anterior inferior iliac spine apophyseal injury with subsequent haematoma formation under the iliacus muscle. There was no evidence of a bleeding disorder. In view of the late presentation, he was managed non-operatively. This injury requires a low threshold for early cross-sectional imaging. The delay in management in this case did not lead to any long-term sequelae. PMID:24859544

  15. Effects of cervical sustained natural apophyseal glide on forward head posture and respiratory function

    PubMed Central

    Kim, Se-Yoon; Kim, Nan-Soo; Kim, Laurentius Jongsoon

    2015-01-01

    [Purpose] To determine the effects of cervical sustained natural apophyseal glide on forward head posture and respiratory function. [Subjects and Methods] Thirty male and female adults in their 20s with forward head posture were included in the study. The subjects were divided randomly into experimental and control groups (n=15 each). Subjects in the experimental group performed cervical sustained natural apophyseal glide three times/week for four weeks while subjects in the control group did not perform the intervention. The craniovertebral angle, forced vital capacity and forced expiratory volume in the first second, as well as the % predicted value of each measurement were assessed to determine the changes in respiration functions before and after the exercise. [Results] The craniovertebral angle four weeks after the experiment was increased in the experimental group, whereas the control group showed no significant difference compared to baseline. The forced vital capacity, forced expiratory volume in the first second, and the % predicted values thereof were significantly increased in the experimental group four weeks after the experiment, but not in the control group. [Conclusion] Cervical sustained natural apophyseal glide was determined to be effective in improving neck posture and respiratory functions for patients with forward head posture. PMID:26180334

  16. Rings

    SciTech Connect

    Davis, R.L.

    1989-01-01

    The essence of vortex physics is that at certain low-energy scales elementary excitations of a point particle theory can behave like strings rather than particles. Vortices are the resulting string-like solutions; their thickness sets the distance scale beyond which physics is string-like rather than particle-like. String degrees of freedom are massless in the sense that excitations on a string can have an arbitrarily low frequency. Non-string degrees of freedom correspond to massive particles and are absent from the low energy spectrum. This article considers only field theories with vortices at low energies. The possible existence of a class of solitons in these vortex theories will be discussed. They are vortex rings: they are localized and finite in energy, and able to carry the quantum numbers of point particles. Rings are thus particle-like solutions of a vortex theory, which is itself a limit of a point particle field theory.

  17. [Lumbar hernia].

    PubMed

    Teiblum, Sandra Sofie; Hjørne, Flemming Pii; Bisgaard, Thue

    2010-03-22

    Lumbar hernia is a rare condition. Lumbar hernia should be considered a rare differential diagnosis to unexplained back pain. Symptoms are scarce and diffuse and can vary with the size and content of the hernia. As there is a 25% risk of incarceration, operation is indicated even in asymptomatic hernias. We report a case of lumbar hernia in a woman with a slow growing mass in the lumbar region. She presented with pain and a computed tomography confirmed the diagnosis. She underwent open surgery and fully recovered with recurrence within the first half year. PMID:20334799

  18. Acromial apophysitis in a 13-year-old adolescent boy: a common condition in an uncommon location

    PubMed Central

    Quinlan, Erin; Bogar, William C.

    2012-01-01

    Objective Traction apophysitis is a common condition in physically active and skeletally immature adolescents. This case study describes the clinical presentation and plain film imaging of traction apophysitis of the acromion process of the scapula. Clinical Features A physically active 13-year-old adolescent boy presented to a chiropractic physician with an acute onset of moderate shoulder pain. Plain film radiographs of the shoulder were performed that revealed fragmentation, sclerosis, and irregularity of the left acromial apophysis. Intervention and Outcome The patient was treated with conservative therapy for 10 weeks, with complete resolution of symptoms. Follow-up radiographs 9 weeks later revealed no radiographic change in the appearance of the apophysis; however, clinical symptoms were absent. The apophyseal growth cartilage is the most vulnerable site in the muscle-tendon unit in the skeletally immature patient and is more susceptible to very small avulsion fractures. Repetitive microtrauma following chronic overuse at a tendon insertion site in a skeletally immature patient may result in traction apophysitis. Conclusions Acromial apophysitis should be included in the differential diagnosis when presented with a young active patient with shoulder pain. Early treatment with restriction of activities is important in the prevention of permanent injury to the acromial cartilaginous growth plate. This case demonstrates that a prompt diagnosis can be made with a careful history, physical examination, and conventional imaging. PMID:23204953

  19. Lumbar spine CT scan

    MedlinePlus

    CAT scan - lumbar spine; Computed axial tomography scan - lumbar spine; Computed tomography scan - lumbar spine; CT - lower back ... stopping.) A computer creates separate images of the spine area, called slices. These images can be stored, ...

  20. Lumbar Osteotomy.

    PubMed

    Wood, Kirkham B

    2016-04-01

    When a patient presents with spine problems, the spine surgeon would do well to avoid use of, reliance on, and acceptance of radiographs as the sole or primary source of information. Measurement of pelvic incidence and lumbar lordosis, although crucial, does not take into account the effort the patient must make to move, the level of involvement of other parts of the body, and the history of previous procedures and outcomes. Radiographs may show pathology that is not consistent with the appearance of the patient. How should we assess this situation? PMID:27015064

  1. Lumbar paraganglioma.

    PubMed

    Dillard-Cannon, Erika; Atsina, Kofi-Buaku; Ghobrial, George; Gnass, Esteban; Curtis, Mark T; Heller, Joshua

    2016-08-01

    Spinal paragangliomas (SP) are benign and overall rare extra-adrenal neuroendocrine tumors often diagnosed during workup for lower back pain. Complete surgical resection achieves both symptomatic relief and cure. We present a 32-year-old man with a longstanding history of lumbago and bilateral lower extremity pain found to have a lumbar paraganglioma at the level of the L3 vertebrae. The clinical, histopathological, and radiological characteristics are described, including the rare finding of superficial siderosis on MRI of the brain. A laminectomy with microscopic dissection of the intradural mass achieved complete debulking without evidence of residual tumor. Excellent prognosis can be achieved with complete surgical resection of SP without the need for adjuvant therapy. Therefore, care should be taken to distinguish these spinal tumors from those that appear similar but are more aggressive. As such, the radiological finding of superficial siderosis should raise the suspicion for SP when a vascular intradural extramedullary spinal tumor is observed. PMID:27032749

  2. The relationship of calcaneal apophyseal ossification and Sanders hand scores to the timing of peak height velocity in adolescents.

    PubMed

    Nicholson, A D; Sanders, J O; Liu, R W; Cooperman, D R

    2015-12-01

    The accurate assessment of skeletal maturity is essential in the management of orthopaedic conditions in the growing child. In order to identify the time of peak height velocity (PHV) in adolescents, two systems for assessing skeletal maturity have been described recently; the calcaneal apophyseal ossification method and the Sanders hand scores. The purpose of this study was to compare these methods in assessing skeletal maturity relative to PHV. We studied the radiographs of a historical group of 94 healthy children (49 females and 45 males), who had been followed longitudinally between the ages of three and 18 years with serial radiographs and physical examination. Radiographs of the foot and hand were undertaken in these children at least annually between the ages of ten and 15 years. We reviewed 738 radiographs of the foot and 694 radiographs of the hand. PHV was calculated from measurements of height taken at the time of the radiographs. Prior to PHV we observed four of six stages of calcaneal apophyseal ossification and two of eight Sanders stages. Calcaneal stage 3 and Sanders stage 2 was seen to occur about 0.9 years before PHV, while calcaneal stage 4 and Sanders stage 3 occurred approximately 0.5 years after PHV. The stages of the calcaneal and Sanders systems can be used in combination, offering better assessment of skeletal maturity with respect to PHV than either system alone. PMID:26637689

  3. Lumbar (Open) Microscopic Discectomy

    MedlinePlus

    ... the most common surgical treatment for ruptured or herniated discs of the lumbar spine. When the outer wall ... a slipped or bulging disc. (See discussion of herniated disc for more information.) Once the inner disc material ...

  4. Herniated Lumbar Disc

    MedlinePlus

    ... 50. A herniated lumbar disc may also cause back pain, although back pain alone (without leg pain) can have many causes ... 90% success); surgery is less effective in relieving back pain. Nonsurgical treatment Your doctor may prescribe nonsurgical treatments ...

  5. Lumbar MRI scan

    MedlinePlus

    ... may need a lumbar MRI if you have: Low back pain that does not get better after treatment Leg ... spine Injury or trauma to the lower spine Low back pain and a history or signs of cancer Multiple ...

  6. [Congenital lumbar hernia].

    PubMed

    Peláez Mata, D J; Alvarez Muñoz, V; Fernández Jiménez, I; García Crespo, J M; Teixidor de Otto, J L

    1998-07-01

    Hernias in the lumbar region are abdominal wall defects that appear in two possible locations: the superior lumbar triangle of Grynfelt-Lesshaft and the inferior lumbar triangle of Petit. There are 40 cases reported in the pediatric literature, and only 16 are considered congenital, associated with the lumbocostovertebral syndrome and/or meningomyelocele. A new case is presented. A premature newborn with a mass in the left flank that increases when the patient cries and reduces easily. The complementary studies confirm the diagnosis of lumbar hernia and reveal the presence of lumbocostovertebral syndrome associated. At the time of operation a well defined fascial defect at the superior lumbar triangle of Grynfelt-Lesshaft is primarily closed. The diagnosis of lumbar hernia is not difficult to establish but it is necessary the screening of the lumbocostovertebral syndrome. We recommend the surgical treatment before 12 months of age; the objective is to close the defect primarily or to use prosthetic material if necessary. PMID:12602034

  7. Failure of the human lumbar motion-segments resulting from anterior shear fatigue loading.

    PubMed

    Skrzypiec, Daniel M; Nagel, Katrin; Sellenschloh, Kay; Klein, Anke; Püschel, Klaus; Morlock, Michael M; Huber, Gerd

    2016-08-01

    An in-vitro experiment was designed to investigate the mode of failure following shear fatigue loading of lumbar motion-segments. Human male lumbar motion-segments (age 32-42 years, n=6) were immersed in Ringer solution at 37°C and repeatedly loaded, using a modified materials testing machine. Fatigue loading consisted of a sinusoidal shear load from 0 N to 1,500 N (750 N±750 N) applied to the upper vertebra of the motion-segment, at a frequency of 5 Hz. During fatigue experiments, several failure events were observed in the dynamic creep curves. Post-test x-ray, CT and dissection revealed that all specimens had delamination of the intervertebral disc. Anterior shear fatigue predominantly resulted in fracture of the apophyseal processes of the upper vertebrae (n=4). Exposure to the anterior shear fatigue loading caused motion-segment instability and resulted in vertebral slip corresponding to grade I and 'mild' grade II spondylolisthesis, as observed clinically. PMID:26829975

  8. Failure of the human lumbar motion-segments resulting from anterior shear fatigue loading

    PubMed Central

    SKRZYPIEC, Daniel M.; NAGEL, Katrin; SELLENSCHLOH, Kay; KLEIN, Anke; PÜSCHEL, Klaus; MORLOCK, Michael M.; HUBER, Gerd

    2016-01-01

    An in-vitro experiment was designed to investigate the mode of failure following shear fatigue loading of lumbar motion-segments. Human male lumbar motion-segments (age 32–42 years, n=6) were immersed in Ringer solution at 37°C and repeatedly loaded, using a modified materials testing machine. Fatigue loading consisted of a sinusoidal shear load from 0 N to 1,500 N (750 N±750 N) applied to the upper vertebra of the motion-segment, at a frequency of 5 Hz. During fatigue experiments, several failure events were observed in the dynamic creep curves. Post-test x-ray, CT and dissection revealed that all specimens had delamination of the intervertebral disc. Anterior shear fatigue predominantly resulted in fracture of the apophyseal processes of the upper vertebrae (n=4). Exposure to the anterior shear fatigue loading caused motion-segment instability and resulted in vertebral slip corresponding to grade I and ‘mild’ grade II spondylolisthesis, as observed clinically. PMID:26829975

  9. Planetary Rings

    NASA Astrophysics Data System (ADS)

    Esposito, Larry

    2014-03-01

    Preface: a personal view of planetary rings; 1. Introduction: the allure of the ringed planets; 2. Studies of planetary rings 1610-2013; 3. Diversity of planetary rings; 4. Individual ring particles and their collisions; 5. Large-scale ring evolution; 6. Moons confine and sculpt rings; 7. Explaining ring phenomena; 8. N-body simulations; 9. Stochastic models; 10. Age and evolution of rings; 11. Saturn's mysterious F ring; 12. Uranus' rings and moons; 13. Neptune's partial rings; 14. Jupiter's ring-moon system after Galileo and New Horizons; 15. Ring photometry; 16. Dusty rings; 17. Concluding remarks; Afterword; Glossary; References; Index.

  10. The Prevalence and Clinical Characteristics of Medial Epicondyle Apophysitis in Juvenile Baseball Player - Ultrasonographic Assessment of 2,926 Cases

    PubMed Central

    Otoshi, Kenichi

    2016-01-01

    Objectives: Apophysitis of humeral medial epicondyle, often referred to as “Little Leaguer’s Elbow, is one of the major throwing injuries in juvenile baseball players as common as osteochondritis dissecans of humeral capitellum. Repetitive valgus stress to the skeletally immature elbow can result in fragmentation, hypertrophy, or separation of the medial epicondyle apophysis, and these injuries may induce elbow pain and adversely influence on elbow function and throwing performance. Although several reports have described various morphological variations of the medial epicondyle apophysis, little is known about the natural course and clinical significance of these variations. The purpose of this study was to investigate the prevalence of these variations in each age group and clarify the association with elbow pain using the large epidemiologic data from medical check-ups of juvenile baseball players. Methods: Of 3,626 juvenile baseball players aged 6 to 17 years, 2,926 players were enrolled in this study. Experience of elbow pain was rated by self-completed questionnaires. Ultrasonographic assessment was used to assess the morphological variations of the antero-inferior medial epicondyle (MEC) and humeral capitellum. Regarding MEC lesion, enthesis of medial ulnar collateral ligament (MUCL) was classified into four types: normal, irregular (IR), fragmentation (FG), and hypertrophy (HT). Osteochondral lesion (OCL) of humeral capitellum was judged by the irregularity or fragmentation of subchondral bone. The prevalence of these lesions was investigated in each age group and evaluated the influence on elbow pain using multivariable logistic regression analysis. Results: The overall prevalence of MEC lesions and capitellum OCL was 49.9% (IR:6.7%, FG:11.7%, HT:31.5%) and 2.1%, respectively. The prevalence of IR and FG gradually increased until reaching its highest at 11-12 years of age. At 12-17 years of age, the prevalence of IR was decreased with age, whereas that

  11. Planetary Rings

    NASA Astrophysics Data System (ADS)

    Esposito, Larry W.

    2011-07-01

    Preface; 1. Introduction: the allure of ringed planets; 2. Studies of planetary rings 1610-2004; 3. Diversity of planetary rings; 4. Individual ring particles and their collisions; 5. Large-scale ring evolution; 6. Moons confine and sculpt rings; 7. Explaining ring phenomena; 8. N-Body simulations; 9. Stochastic models; 10. Age and evolution of rings; 11. Saturn's mysterious F ring; 12. Neptune's partial rings; 13. Jupiter's ring-moon system after Galileo; 14. Ring photometry; 15. Dusty rings; 16. Cassini observations; 17. Summary: the big questions; Glossary; References; Index.

  12. Lumbar Spinal Stenosis.

    PubMed

    Feeney, Richard

    2016-06-01

    Questions from patients about pain conditions and analgesic pharmacotherapy and responses from authors are presented to help educate patients and make them more effective self-advocates. In reply to a question, lumbar spinal stenosis, commonly a multifactorial disease that can have profound functional consequences, is considered, along with a discussion of physical and pharmacologic treatments and quality of life. PMID:27145444

  13. Lumbar corsets can decrease lumbar motion in golf swing.

    PubMed

    Hashimoto, Koji; Miyamoto, Kei; Yanagawa, Takashi; Hattori, Ryo; Aoki, Takaaki; Matsuoka, Toshio; Ohno, Takatoshi; Shimizu, Katsuji

    2013-01-01

    Swinging a golf club includes the rotation and extension of the lumbar spine. Golf-related low back pain has been associated with degeneration of the lumbar facet and intervertebral discs, and with spondylolysis. Reflective markers were placed directly onto the skin of 11young male amateur golfers without a previous history of back pain. Using a VICON system (Oxford Metrics, U.K.), full golf swings were monitored without a corset (WOC), with a soft corset (SC), and with a hard corset (HC), with each subject taking 3 swings. Changes in the angle between the pelvis and the thorax (maximum range of motion and angular velocity) in 3 dimensions (lumbar rotation, flexion-extension, and lateral tilt) were analyzed, as was rotation of the hip joint. Peak changes in lumbar extension and rotation occurred just after impact with the ball. The extension angle of the lumbar spine at finish was significantly lower under SC (38°) or HC (28°) than under WOC (44°) conditions (p < 0.05). The maximum angular velocity after impact was significantly smaller under HC (94°/sec) than under SC (177°/sec) and WOC (191° /sec) conditions, as were the lumbar rotation angles at top and finish. In contrast, right hip rotation angles at top showed a compensatory increase under HC conditions. Wearing a lumbar corset while swinging a golf club can effectively decrease lumbar extension and rotation angles from impact until the end of the swing. These effects were significantly enhanced while wearing an HC. Key pointsRotational and extension forces on the lumbar spine may cause golf-related low back painWearing lumbar corsets during a golf swing can effectively decrease lumbar extension and rotation angles and angular velocity.Wearing lumbar corsets increased the rotational motion of the hip joint while reducing the rotation of the lumbar spine. PMID:24149729

  14. Lumbar Corsets Can Decrease Lumbar Motion in Golf Swing

    PubMed Central

    Hashimoto, Koji; Miyamoto, Kei; Yanagawa, Takashi; Hattori, Ryo; Aoki, Takaaki; Matsuoka, Toshio; Ohno, Takatoshi; Shimizu, Katsuji

    2013-01-01

    Swinging a golf club includes the rotation and extension of the lumbar spine. Golf-related low back pain has been associated with degeneration of the lumbar facet and intervertebral discs, and with spondylolysis. Reflective markers were placed directly onto the skin of 11young male amateur golfers without a previous history of back pain. Using a VICON system (Oxford Metrics, U.K.), full golf swings were monitored without a corset (WOC), with a soft corset (SC), and with a hard corset (HC), with each subject taking 3 swings. Changes in the angle between the pelvis and the thorax (maximum range of motion and angular velocity) in 3 dimensions (lumbar rotation, flexion-extension, and lateral tilt) were analyzed, as was rotation of the hip joint. Peak changes in lumbar extension and rotation occurred just after impact with the ball. The extension angle of the lumbar spine at finish was significantly lower under SC (38°) or HC (28°) than under WOC (44°) conditions (p < 0.05). The maximum angular velocity after impact was significantly smaller under HC (94°/sec) than under SC (177°/sec) and WOC (191° /sec) conditions, as were the lumbar rotation angles at top and finish. In contrast, right hip rotation angles at top showed a compensatory increase under HC conditions. Wearing a lumbar corset while swinging a golf club can effectively decrease lumbar extension and rotation angles from impact until the end of the swing. These effects were significantly enhanced while wearing an HC. Key points Rotational and extension forces on the lumbar spine may cause golf-related low back pain Wearing lumbar corsets during a golf swing can effectively decrease lumbar extension and rotation angles and angular velocity. Wearing lumbar corsets increased the rotational motion of the hip joint while reducing the rotation of the lumbar spine. PMID:24149729

  15. Lumbar spinal stenosis.

    PubMed Central

    Ciricillo, S F; Weinstein, P R

    1993-01-01

    Lumbar spinal stenosis, the results of congenital and degenerative constriction of the neural canal and foramina leading to lumbosacral nerve root or cauda equina compression, is a common cause of disability in middle-aged and elderly patients. Advanced neuroradiologic imaging techniques have improved our ability to localize the site of nerve root entrapment in patients presenting with neurogenic claudication or painful radiculopathy. Although conservative medical management may be successful initially, surgical decompression by wide laminectomy or an intralaminar approach should be done in patients with serious or progressive pain or neurologic dysfunction. Because the early diagnosis and treatment of lumbar spinal stenosis may prevent intractable pain and the permanent neurologic sequelae of chronic nerve root entrapment, all physicians should be aware of the different neurologic presentations and the treatment options for patients with spinal stenosis. Images PMID:8434469

  16. [Lumbar spinal angiolipoma].

    PubMed

    Isla, Alberto; Ortega Martinez, Rodrigo; Pérez López, Carlos; Gómez de la Riva, Alvaro; Mansilla, Beatriz

    2016-01-01

    Spinal angiolipomas are fairly infrequent benign tumours that are usually located in the epidural space of the thoracic column and represent 0.14% to 1.3% of all spinal tumours. Lumbar angiolipomas are extremely rare, representing only 9.6% of all spinal extradural angiolipomas. We report the case of a woman who complained of a lumbar pain of several months duration with no neurological focality and that had intensified in the last three days without her having had any injury or made a physical effort. The MR revealed an extradural mass L1-L2, on the posterior face of the medulla, decreasing the anteroposterior diameter of the canal. The patient symptoms improved after surgery. Total extirpation of the lesion is possible in most cases, and the prognosis is excellent even if the lesion is infiltrative. For this reason, excessively aggressive surgery is not necessary to obtain complete resection. PMID:27263067

  17. LUMBAR DISC HERNIATION

    PubMed Central

    Vialle, Luis Roberto; Vialle, Emiliano Neves; Suárez Henao, Juan Esteban; Giraldo, Gustavo

    2015-01-01

    Lumbar disc herniation is the most common diagnosis among the degenerative abnormalities of the lumbar spine (affecting 2 to 3% of the population), and is the principal cause of spinal surgery among the adult population. The typical clinical picture includes initial lumbalgia, followed by progressive sciatica. The natural history of disc herniation is one of rapid resolution of the symptoms (four to six weeks). The initial treatment should be conservative, managed through medication and physiotherapy, sometimes associated with percutaneous nerve root block. Surgical treatment is indicated if pain control is unsuccessful, if there is a motor deficit greater than grade 3, if there is radicular pain associated with foraminal stenosis, or if cauda equina syndrome is present. The latter represents a medical emergency. A refined surgical technique, with removal of the extruded fragment and preservation of the ligamentum flavum, resolves the sciatic symptoms and reduces the risk of recurrence over the long term. PMID:27019834

  18. Lumbar spine chordoma

    PubMed Central

    Hatem, M.A.

    2015-01-01

    Chordoma is a rare tumor arising from notochord remnants in the spine. It is slow-growing, which makes it difficult to diagnose and difficult to follow up after treatment. Typically, it occurs in the base of the skull and sacrococcygeal spine; it rarely occurs in other parts of the spine. CT-guided biopsy of a suspicious mass enabled diagnosis of lumbar spine chordoma.

  19. Lumbar spinal surgery - series (image)

    MedlinePlus

    ... of bones (vertebrae) separated by soft cushions (intervertebral discs). ... Lumbar (lower back) spine disease is usually caused by herniated ... bodies (osteophytes), which compress spinal nerves, trauma, and ...

  20. The effect of sustained natural apophyseal glide (SNAG) combined with neurodynamics in the management of a patient with cervical radiculopathy: a case report.

    PubMed

    Anandkumar, Sudarshan

    2015-02-01

    This case report describes a 47-year-old female who presented with complaints of pain in the right elbow radiating down to the thumb. Physical examination revealed symptom reproduction with Spurling A test, upper limb neurodynamic testing-1 and right cervical rotation along with reduced symptoms with neck distraction. Clinical diagnosis of cervical radiculopathy (CR) was made based on a clinical prediction rule. This case report speculates a potentially first-time description of successful conservative management of CR in a patient utilizing simultaneous combination of sustained natural apophyseal glide and neurodynamic mobilization. Immediate improvements were seen in pain, cervical range of motion and functional abilities. The patient was discharged from physical therapy by the second week after four treatment sessions with complete pain resolution maintained at a four-month follow-up period. PMID:25329587

  1. Planetary rings

    SciTech Connect

    Greenberg, R.; Brahic, A.

    1984-01-01

    Among the topics discussed are the development history of planetary ring research, the view of planetary rings in astronomy and cosmology over the period 1600-1900, the characteristics of the ring systems of Saturn and Uranus, the ethereal rings of Jupiter and Saturn, dust-magnetosphere interactions, the effects of radiation forces on dust particles, the collisional interactions and physical nature of ring particles, transport effects due to particle erosion mechanisms, and collision-induced transport processes in planetary rings. Also discussed are planetary ring waves, ring particle dynamics in resonances, the dynamics of narrow rings, the origin and evolution of planetary rings, the solar nebula and planetary disk, future studies of the planetary rings by space probes, ground-based observatories and earth-orbiting satellites, and unsolved problems in planetary ring dynamics.

  2. Upper lumbar disk herniations.

    PubMed

    Cedoz, M E; Larbre, J P; Lequin, C; Fischer, G; Llorca, G

    1996-06-01

    Specific features of upper lumbar disk herniations are reviewed based on data from the literature and from a retrospective study of 24 cases treated surgically between 1982 and 1994 (seven at L1-L2 and 17 at L2-L3). Clinical manifestations are polymorphic, misleading (abdominogenital pain suggestive of a visceral or psychogenic condition, meralgia paresthetica, isolated sciatica; femoral neuralgia is uncommon) and sometimes severe (five cases of cauda equina syndrome in our study group). The diagnostic usefulness of imaging studies (radiography, myelography, computed tomography, magnetic resonance imaging) and results of surgery are discussed. The risk of misdiagnosis and the encouraging results of surgery are emphasized. PMID:8817752

  3. Mimickers of lumbar radiculopathy.

    PubMed

    Grimm, Bennett Douglas; Blessinger, Brian Joseph; Darden, Bruce Vaiden; Brigham, Craig D; Kneisl, Jeffrey S; Laxer, Eric B

    2015-01-01

    Orthopaedic surgeons frequently treat patients who report pain that radiates from the back into the lower extremity. Although the most common etiology is either a herniated disk or spinal stenosis, a myriad of pathologies can mimic the symptoms of radiculopathy, resulting in differences in the clinical presentation and the workup. Therefore, the clinician must be able to distinguish the signs and symptoms of lumbar radiculopathy from pathologies that may have a similar presentation. Being cognizant of these other possible conditions enables the physician to consider a breadth of alternative diagnoses when a patient presents with radiating lower extremity pain. PMID:25538126

  4. Herniated lumbar disc

    PubMed Central

    2011-01-01

    Introduction Herniated lumbar disc is a displacement of disc material (nucleus pulposus or annulus fibrosis) beyond the intervertebral disc space. The highest prevalence is among people aged 30 to 50 years, with a male to female ratio of 2:1. There is little evidence to suggest that drug treatments are effective in treating herniated disc. Methods and outcomes We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of drug treatments, non-drug treatments, and surgery for herniated lumbar disc? We searched: Medline, Embase, The Cochrane Library, and other important databases up to June 2010 (Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). Results We found 37 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions. Conclusions In this systematic review, we present information relating to the effectiveness and safety of the following interventions: acupuncture, advice to stay active, analgesics, antidepressants, bed rest, corticosteroids (epidural injections), cytokine inhibitors (infliximab), discectomy (automated percutaneous, laser, microdiscectomy, standard), exercise therapy, heat, ice, massage, muscle relaxants, non-steroidal anti-inflammatory drugs (NSAIDs), percutaneous disc decompression, spinal manipulation, and traction. PMID:21711958

  5. Saturn's rings

    NASA Technical Reports Server (NTRS)

    2000-01-01

    When seen from the unlit side, the rings of Saturn present a much different appearance from that familiar to telescopic observers. Relatively opaque areas like the B Ring turn black, while lightly populated zones, such as the C Ring and the Cassini Division, prove to excellent diffuse transmitters of sunlight. The A Ring, with intermediate opacity, is at an intermediate level of brightness.

  6. Outcome of Salvage Lumbar Fusion after Lumbar Arthroplasty

    PubMed Central

    Deutsch, Harel

    2014-01-01

    Study Design Retrospective review. Purpose This study aims to define the role of lumbar fusion for persistent back pains after the lumbar disc replacement. Overview of Literature Little is written about lumbar fusion after optimally placed lumbar arthroplasty in patients with persistent lower back pains. Methods Retrospective review of cases of lumbar artificial disc requiring subsequent fusion because of persistent back pains despite optimally placed artificial discs. Outcomes were evaluated using Oswestry Disability Index (ODI) and visual analogue scale (VAS). Clinical improvements indicated 25% improvement in ODI and VAS values. Results Five patients met the study criteria. The mean baseline ODI for the five patients was 52. The mean baseline VAS scores for back and leg pains were 76 and 26, respectively. All the five patients had optimally placed prosthesis. The indication for surgery was the constant low back pains found in all the patients. Revision surgery involved disc explantation and fusion in two of the patients and posterolateral fusion without removing the prosthesis in three. None of the patients achieved adequate pain control after the revision surgery despite the solid bony fusion documented by postoperative computed tomography. The mean ODI value after the fusion was 55. The mean values for back and leg pains VAS were 72 and 30, respectively. Conclusions Lack of good pain relief after successful lumbar artifical disc replacements may indicate different etiology for the back pains. The spine-treating surgeons should have a high threshold level to perform salvage fusion at that level. PMID:24596600

  7. Saturn's Rings

    NASA Astrophysics Data System (ADS)

    Cuzzi, J. N.

    2014-12-01

    The rings are changing before our eyes; structure varies on all timescales and unexpected things have been discovered. Many questions have been answered, but some answers remain elusive (see Cuzzi et al 2010 for a review). Here we highlight the major ring science progress over the mission to date, and describe new observations planned for Cassini's final three years. Ring Composition and particle sizes: The rings are nearly all water ice with no other ices - so why are they reddish? The C Ring and Cassini Division are "dirtier" than the more massive B and A Rings, as shown by near-IR and, recently, microwave observations. Particle sizes, from stellar and radio occultations, vary from place to place. Ring structure, micro and macro: numerous spiral density waves and ubiquitous "self-gravity wakes" reveal processes which fostered planet formation in the solar system and elsewhere. However, big puzzles remain regarding the main ring divisions, the C Ring plateau structures, and the B Ring irregular structure. Moonlets, inside and out, seen and unseen: Two gaps contain sizeable moonlets, but more gaps seem to contain none; even smaller embedded "propeller" objects wander, systematically or randomly, through the A ring. Rubble pile ringmoons just outside the rings may escaped from the rings, and the recently discovered "Peggy" may be trying this as we watch. Impact bombardment of the rings: Comet fragments set the rings to rippling on century-timescales, and boulders crash through hourly; meanwhile, the constant hail of infalling Kuiper belt material has a lower mass flux than previously thought. Origin and Age of the Rings: The ring mass and bombardment play key roles. The ring mass is well known everywhere but in the B Ring (where most of it is). New models suggest how tidal breakup of evolving moons may have formed massive ancient rings, of which the current ring is just a shadow. During its last three years, the Cassini tour profile will allow entirely new

  8. Vascular ring

    MedlinePlus

    ... with aberrant subclavian and left ligamentum ateriosus; Congenital heart defect - vascular ring; Birth defect heart - vascular ring ... accounts for less than 1% of all congenital heart problems. The condition occurs as often in males ...

  9. Neptune's rings

    NASA Technical Reports Server (NTRS)

    1999-01-01

    This 591-second exposure of the rings of Neptune were taken with the clear filter by the Voyager 2 wide-angle camera. The two main rings are clearly visible and appear complete over the region imaged. Also visible in this image is the inner faint ring and the faint band which extends smoothly from the ring roughly halfway between the two bright rings. Both of these newly discovered rings are broad and much fainter than the two narrow rings. The bright glare is due to over-exposure of the crescent on Neptune. Numerous bright stars are evident in the background. Both bright rings have material throughout their entire orbit, and are therefore continuous. The Voyager Mission is conducted by JPL for NASA's Office of Space Science and Applications.

  10. [Congenital lumbar hernia and bilateral renal agenesis].

    PubMed

    Barrero Candau, R; Garrido Morales, M

    2007-04-01

    We report a new case of congenital lumbar hernia. This is first case reported of congenital lumbar hernia and bilateral renal agenesis. We review literature and describe associated malformations reported that would be role out in every case of congenital lumbar hernia. PMID:17650728

  11. Planetary Rings

    NASA Astrophysics Data System (ADS)

    Gordon, M. K.; Araki, S.; Black, G. J.; Bosh, A. S.; Brahic, A.; Brooks, S. M.; Charnoz, S.; Colwell, J. E.; Cuzzi, J. N.; Dones, L.; Durisen, R. H.; Esposito, L. W.; Ferrari, C.; Festou, M.; French, R. G.; Giuliatti-Winter, S. M.; Graps, A. L.; Hamilton, D. P.; Horanyi, M.; Karjalainen, R. M.; Krivov, A. V.; Krueger, H.; Larson, S. M.; Levison, H. F.; Lewis, M. C.; Lissauer, J. J.; Murray, C. D.; Namouni, F.; Nicholson, P. D.; Olkin, C. B.; Poulet, F.; Rappaport, N. J.; Salo, H. J.; Schmidt, J.; Showalter, M. R.; Spahn, F.; Spilker, L. J.; Srama, R.; Stewart, G. R.; Yanamandra-Fisher, P.

    2002-08-01

    The past two decades have witnessed dramatic changes in our view and understanding of planetary rings. We now know that each of the giant planets in the Solar System possesses a complex and unique ring system. Recent studies have identified complex gravitational interactions between the rings and their retinues of attendant satellites. Among the four known ring systems, we see elegant examples of Lindblad and corotation resonances (first invoked in the context of galactic disks), electromagnetic resonances, spiral density waves and bending waves, narrow ringlets which exhibit internal modes due to collective instabilities, sharp-edged gaps maintained via tidal torques from embedded moonlets, and tenuous dust belts created by meteoroid impact onto, or collisions between, parent bodies. Yet, as far as we have come, our understanding is far from complete. The fundamental questions confronting ring scientists at the beginning of the twenty-first century are those regarding the origin, age and evolution of the various ring systems, in the broadest context. Understanding the origin and age requires us to know the current ring properties, and to understand the dominant evolutionary processes and how they influence ring properties. Here we discuss a prioritized list of the key questions, the answers to which would provide the greatest improvement in our understanding of planetary rings. We then outline the initiatives, missions, and other supporting activities needed to address those questions, and recommend priorities for the coming decade in planetary ring science.

  12. Lumbar reservoir for intrathecal chemotherapy.

    PubMed

    Dyck, P

    1985-06-15

    The Ommaya ventricular reservoir has been the standby of intrathecal chemotherapy for more than a decade, in spite of some specific drawbacks. A general anaesthetic is often required. The scalp must be shaven. Ventricular puncture may not always be easy and keeping the ventricular catheter patent is sometimes difficult. Hence the author has adapted a commercially available lumbar peritoneal shunt system to function as a lumbar intrathecal reservoir. The procedure is simple and can be performed expeditiously under local anaesthesia. To date, eight cases have received intrathecal chemotherapy by this means. PMID:3838918

  13. Lumbar discogram resulting from lumbar interlaminar epidural injection.

    PubMed

    Huang, Jeffrey; Kwa, Andre

    2004-06-01

    Lumbar discography is a diagnostic modality to determine whether the intervertebral disc is the cause of pain. The injection of radiopaque contrast into the nucleus pulposus of the disc can reveal the internal details of the disc. We describe a case of inadvertent lumbar discogram resulting from an attempted lumbar interlaminar epidural injection at L5-S1 under fluoroscopy. The patient did not have a postdural puncture headache or nerve root irritation. The potential triangle in the lateral aspect of spinal cord may be the explanation for this situation, because this triangle is composed of the exiting nerve root laterally, the lateral margin of the dura medially, and the pedicle as its base. The L5-S1 disc is located in the center of the triangle. In our case, the Tuohy needle was placed possibly in the center of the triangle, too laterally to puncture the dura. Hence, the patient did not suffer from postdural puncture headache. The needle was probably inferior to the nerve root, and no obvious nerve root trauma or irritation occurred. This potential triangle may provide alternative access for lumbar discography at the L5-S1 level. PMID:15261324

  14. Lumbar discography: an update.

    PubMed

    Anderson, Mark W

    2004-01-01

    and then come back to reinject more contrast into the disk in question. As radiologists, we tend to focus on the technical aspects of a procedure and the anatomic/morphologic information it provides. However, it cannot be emphasized enough that when performing lumbar discography, the assessment of the patient's pain response during the injection is the most important component of the procedure, and requires not only technical skills, but an understanding of how best to avoid some of the pitfalls that can lead to inaccurate results. PMID:14976837

  15. Planetary Rings

    NASA Technical Reports Server (NTRS)

    Cuzzi, Jeffrey N.

    1994-01-01

    Just over two decades ago, Jim Pollack made a critical contribution to our understanding of planetary ring particle properties, and resolved a major apparent paradox between radar reflection and radio emission observations. At the time, particle properties were about all there were to study about planetary rings, and the fundamental questions were, why is Saturn the only planet with rings, how big are the particles, and what are they made of? Since then, we have received an avalanche of observations of planetary ring systems, both from spacecraft and from Earth. Meanwhile, we have seen steady progress in our understanding of the myriad ways in which gravity, fluid and statistical mechanics, and electromagnetism can combine to shape the distribution of the submicron-to-several-meter size particles which comprise ring systems into the complex webs of structure that we now know them to display. Insights gained from studies of these giant dynamical analogs have carried over into improved understanding of the formation of the planets themselves from particle disks, a subject very close to Jim's heart. The now-complete reconnaissance of the gas giant planets by spacecraft has revealed that ring systems are invariably found in association with families of regular satellites, and there is ark emerging perspective that they are not only physically but causally linked. There is also mounting evidence that many features or aspects of all planetary ring systems, if not the ring systems themselves, are considerably younger than the solar system

  16. Management of lumbar spinal stenosis.

    PubMed

    Lurie, Jon; Tomkins-Lane, Christy

    2016-01-01

    Lumbar spinal stenosis (LSS) affects more than 200,000 adults in the United States, resulting in substantial pain and disability. It is the most common reason for spinal surgery in patients over 65 years. Lumbar spinal stenosis is a clinical syndrome of pain in the buttocks or lower extremities, with or without back pain. It is associated with reduced space available for the neural and vascular elements of the lumbar spine. The condition is often exacerbated by standing, walking, or lumbar extension and relieved by forward flexion, sitting, or recumbency. Clinical care and research into lumbar spinal stenosis is complicated by the heterogeneity of the condition, the lack of standard criteria for diagnosis and inclusion in studies, and high rates of anatomic stenosis on imaging studies in older people who are completely asymptomatic. The options for non-surgical management include drugs, physiotherapy, spinal injections, lifestyle modification, and multidisciplinary rehabilitation. However, few high quality randomized trials have looked at conservative management. A systematic review concluded that there is insufficient evidence to recommend any specific type of non-surgical treatment. Several different surgical procedures are used to treat patients who do not improve with non-operative therapies. Given that rapid deterioration is rare and that symptoms often wax and wane or gradually improve, surgery is almost always elective and considered only if sufficiently bothersome symptoms persist despite trials of less invasive interventions. Outcomes (leg pain and disability) seem to be better for surgery than for non-operative treatment, but the evidence is heterogeneous and often of limited quality. PMID:26727925

  17. Effect of Lumbar Stabilization and Dynamic Lumbar Strengthening Exercises in Patients With Chronic Low Back Pain

    PubMed Central

    Moon, Hye Jin; Kim, Dae Ha; Kim, Ha Jeong; Cho, Young Ki; Lee, Kwang Hee; Kim, Jung Hoo; Choi, Yoo Jung

    2013-01-01

    Objective To compare the effects of lumbar stabilization exercises and lumbar dynamic strengthening exercises on the maximal isometric strength of the lumbar extensors, pain severity and functional disability in patients with chronic low back pain (LBP). Methods Patients suffering nonspecific LBP for more than 3 months were included prospectively and randomized into lumbar stabilization exercise group (n=11) or lumbar dynamic strengthening exercise group (n=10). Exercises were performed for 1 hour, twice weekly, for 8 weeks. The strength of the lumbar extensors was measured at various angles ranging from 0° to 72° at intervals of 12°, using a MedX. The visual analog scale (VAS) and the Oswestry Low Back Pain Disability Questionnaire (ODQ) were used to measure the severity of LBP and functional disability before and after the exercise. Results Compared with the baseline, lumbar extension strength at all angles improved significantly in both groups after 8 weeks. The improvements were significantly greater in the lumbar stabilization exercise group at 0° and 12° of lumbar flexion. VAS decreased significantly after treatment; however, the changes were not significantly different between the groups. ODQ scores improved significantly in the stabilization exercise group only. Conclusion Both lumbar stabilization and dynamic strengthening exercise strengthened the lumbar extensors and reduced LBP. However, the lumbar stabilization exercise was more effective in lumbar extensor strengthening and functional improvement in patients with nonspecific chronic LBP. PMID:23525973

  18. Lumbar epidural varices: An unusual cause of lumbar claudication.

    PubMed

    Subbiah, Meenakshisundaram; Yegumuthu, Krishnan

    2016-01-01

    Lumbar epidural varices can also present with radiculopathy similar to acute intervertebral disc prolapse (IVDP). However as the magnetic resonance imaging (MRI) in these patients are usually normal without significant compressive lesions of the nerve roots, the diagnosis is commonly missed or delayed leading to persistent symptoms. We present a rare case of acute severe unilateral claudication with a normal MRI unresponsive to conservative management who was treated surgically. The nerve root on the symptomatic side was found to be compressed by large anterior epidural varices secondary to an abnormal cranial attachment of ligamentum flavum. Decompression of the root and coagulation of the varices resulted in complete pain relief. To conclude, lumbar epidural varices should be considered in the differential diagnosis of acute onset radiculopathy and claudication in the absence of significant MRI findings. PMID:27512228

  19. Lumbar epidural varices: An unusual cause of lumbar claudication

    PubMed Central

    Subbiah, Meenakshisundaram; Yegumuthu, Krishnan

    2016-01-01

    Lumbar epidural varices can also present with radiculopathy similar to acute intervertebral disc prolapse (IVDP). However as the magnetic resonance imaging (MRI) in these patients are usually normal without significant compressive lesions of the nerve roots, the diagnosis is commonly missed or delayed leading to persistent symptoms. We present a rare case of acute severe unilateral claudication with a normal MRI unresponsive to conservative management who was treated surgically. The nerve root on the symptomatic side was found to be compressed by large anterior epidural varices secondary to an abnormal cranial attachment of ligamentum flavum. Decompression of the root and coagulation of the varices resulted in complete pain relief. To conclude, lumbar epidural varices should be considered in the differential diagnosis of acute onset radiculopathy and claudication in the absence of significant MRI findings. PMID:27512228

  20. Assessment of Lumbar Lordosis and Lumbar Core Strength in Information Technology Professionals

    PubMed Central

    Mehta, Roma Satish; Dabadghav, Rachana; Rairikar, Savita; Shayam, Ashok; Sancheti, Parag

    2016-01-01

    Study Design Observational study. Purpose To correlate lumbar lordosis and lumbar core strength in information technology (IT) professionals. Overview of Literature IT professionals have to work for long hours in a sitting position, which can affect lumbar lordosis and lumbar core strength. Methods Flexicurve was used to assess the lumbar lordosis, and pressure biofeedback was used to assess the lumbar core strength in the IT professionals. All subjects, both male and female, with and without complaint of low back pain and working for two or more years were included, and subjects with a history of spinal surgery or spinal deformity were excluded from the study. Analysis was done using Pearson's correlation. Results For the IT workers, no correlation was seen between lumbar lordosis and lumbar core strength (r=–0.04); however, a weak negative correlation was seen in IT people who complained of pain (r=–0.12), while there was no correlation of lumbar lordosis and lumbar core in IT people who had no complains of pain (r=0.007). Conclusions The study shows that there is no correlation of lumbar lordosis and lumbar core strength in IT professionals, but a weak negative correlation was seen in IT people who complained of pain. PMID:27340529

  1. [Spontaneous resolution of a lumbar disc herniation].

    PubMed

    Gelabert-González, M; Serramito-García, R; Aran-Echabe, E; García-Allut, A

    2007-04-01

    Lumbar disc herniation is a common cause of lower leg radiculopathy and the most effective methods of treatment remain in question. Both surgical and nonsurgical treatments may provide a successful outcome in appropriately selected patients. The spontaneous resolution of herniated lumbar discs is a well-established phenomenon. The authors present a case of spontaneous regression of a herniated lumbar nucleus pulpous in a patient with radiculopathy. PMID:17497061

  2. Nerve Wrapping of the Sciatic Nerve With Acellular Dermal Matrix in Chronic Complete Proximal Hamstring Ruptures and Ischial Apophyseal Avulsion Fractures

    PubMed Central

    Haus, Brian M.; Arora, Danny; Upton, Joseph; Micheli, Lyle J.

    2016-01-01

    Background: Patients with chronic injuries of the proximal hamstring can develop significant impairment because of weakness of the hamstring muscles, sciatic nerve compression from scar formation, or myositis ossificans. Purpose: To describe the surgical outcomes of patients with chronic injury of the proximal hamstrings who were treated with hamstring repair and sciatic neurolysis supplemented with nerve wrapping with acellular dermal matrix. Study Design: Retrospective case series; Level of evidence, 4. Methods: Fifteen consecutive patients with a diagnosis of chronic complete proximal hamstring rupture or chronic ischial tuberosity apophyseal avulsion fracture (mean age, 39.67 years; range, 14-69 years) were treated with proximal hamstring repair and sciatic neurolysis supplemented with nerve wrapping with acellular dermal matrix. Nine patients had preoperative sciatica, and 6 did not. Retrospective chart review recorded clinical outcomes measured by the degree of pain relief, the rate of return to activities, and associated postoperative complications. Results: All 15 patients were followed in the postoperative period for an average of 16.6 months. Postoperatively, there were 4 cases of transient sciatic nerve neurapraxia. Four patients (26%) required postoperative betamethasone sodium phosphate (Celestone Soluspan) injectable suspension USP 6 mg/mL. Among the 9 patients with preoperative sciatica, 6 (66%) had a good or excellent outcome and were able to return to their respective activities/sports; 3 (33%) had persistent chronic pain. One of these had persistent sciatic neuropathy that required 2 surgical reexplorations and scar excision after development of recurrent extraneural scar formation. Among the 6 without preoperative sciatica, 100% had a good or excellent outcomes and 83% returned to their respective activities/sports. Better outcomes were observed in younger patients, as the 3 cases of persistent chronic sciatic pain were in patients older than 45

  3. The human lumbar dorsal rami.

    PubMed Central

    Bogduk, N; Wilson, A S; Tynan, W

    1982-01-01

    The L 1-4 dorsal rami tend to form three branches, medial, lateral, and intermediate, which are distributed, respectively, to multifidus, iliocostalis, and longissimus. The intertransversarii mediales are innervated by a branch of the dorsal ramus near the origin of the medial branch. The L 4 dorsal ramus regularly forms three branches while the L 1-3 levels the lateral and intermediate branches may, alternatively, arise from a short common stem. The L 5 dorsal ramus is much longer than the others and forms only a medial and an intermediate branch. Each lumbar medial branch innervates two adjacent zygapophysial joints and ramifies in multifidus, supplying only those fascicles which arise from the spinous process with the same segmental number as the nerve. The comparative anatomy of the lumbar dorsal rami is discussed and the applied anatomy with respect to 'rhizolysis', 'facet denervation' and diagnostic paraspinal electromyography is described. PMID:7076562

  4. Vascular rings.

    PubMed

    Backer, Carl L; Mongé, Michael C; Popescu, Andrada R; Eltayeb, Osama M; Rastatter, Jeffrey C; Rigsby, Cynthia K

    2016-06-01

    The term vascular ring refers to congenital vascular anomalies of the aortic arch system that compress the esophagus and trachea, causing symptoms related to those two structures. The most common vascular rings are double aortic arch and right aortic arch with left ligamentum. Pulmonary artery sling is rare and these patients need to be carefully evaluated for frequently associated tracheal stenosis. Another cause of tracheal compression occurring only in infants is the innominate artery compression syndrome. In the current era, the diagnosis of a vascular ring is best established by CT imaging that can accurately delineate the anatomy of the vascular ring and associated tracheal pathology. For patients with a right aortic arch there recently has been an increased recognition of a structure called a Kommerell diverticulum which may require resection and transfer of the left subclavian artery to the left carotid artery. A very rare vascular ring is the circumflex aorta that is now treated with the aortic uncrossing operation. Patients with vascular rings should all have an echocardiogram because of the incidence of associated congenital heart disease. We also recommend bronchoscopy to assess for additional tracheal pathology and provide an assessment of the degree of tracheomalacia and bronchomalacia. The outcomes of surgical intervention are excellent and most patients have complete resolution of symptoms over a period of time. PMID:27301603

  5. Laparoscopic total extraperitoneal repair of lumbar hernia

    PubMed Central

    Lim, Man Sup; Lee, Hae Wan; Yu, Chang Hee

    2011-01-01

    Lumbar hernia is a rare surgical entity without a standard method of repair. With advancements in laparoscopic techniques, successful lumbar herniorrhaphy can be achieved by the creation of a completely extraperitoneal working space and secure fixation of a wide posterior mesh. We present a total extraperitoneal laparoendoscopic repair of lumbar hernia, which allowed for minimal invasiveness while providing excellent anatomical identification, easy mobilization of contents and wide secure mesh fixation. A total extraperitoneal method of lumbar hernia repair by laparoscopic approach is feasible and may be an ideal option. PMID:22111086

  6. Lumbar lordosis of extinct hominins.

    PubMed

    Been, Ella; Gómez-Olivencia, Asier; Kramer, Patricia A

    2012-01-01

    The lordotic curvature of the lumbar spine (lumbar lordosis) in humans is a critical component in the ability to achieve upright posture and bipedal gait. Only general estimates of the lordotic angle (LA) of extinct hominins are currently available, most of which are based on the wedging of the vertebral bodies. Recently, a new method for calculating the LA in skeletal material has become available. This method is based on the relationship between the lordotic curvature and the orientation of the inferior articular processes relative to vertebral bodies in the lumbar spines of living primates. Using this relationship, we developed new regression models in order to calculate the LAs in hominins. The new models are based on primate group-means and were used to calculate the LAs in the spines of eight extinct hominins. The results were also compared with the LAs of modern humans and modern nonhuman apes. The lordotic angles of australopithecines (41° ± 4), H. erectus (45°) and fossil H. sapiens (54° ± 14) are similar to those of modern humans (51° ± 11). This analysis confirms the assumption that human-like lordotic curvature was a morphological change that took place during the acquisition of erect posture and bipedalism as the habitual form of locomotion. Neandertals have smaller lordotic angles (LA = 29° ± 4) than modern humans, but higher angles than nonhuman apes (22° ± 3). This suggests possible subtle differences in Neandertal posture and locomotion from that of modern humans. PMID:22052243

  7. Retroperitoneal laparoscopic bilateral lumbar sympathectomy.

    PubMed

    Segers, B; Himpens, J; Barroy, J P

    2007-06-01

    The first retroperitoneal lumbar sympathectomy was performed in 1924 by Julio Diez. The classic procedure for sympathectomy is open surgery. We report a unilateral laparoscopic retroperitoneal approach to perform bilateral lumbar sympathectomy. This approach was performed for a 43-year-old man with distal arterial occlusive disease and no indication for direct revascularization. His predominant symptoms were intermittent claudication at 100 metres and cold legs. The patient was placed in a left lateral decubitus position. The optical system was placed first in an intra-abdominal position to check that the trocars were well positioned in the retroperitoneal space. The dissection of retroperitoneum was performed by CO2 insufflation. The inferior vena cava was reclined and the right sympathetic chain was individualized. Two ganglia (L3-L4) were removed by bipolar electro-coagulation. The aorta was isolated on a vessel loop and careful anterior traction allowed a retro-aortic pre-vertebral approach between the lumbar vessels. The left sympathetic chain was dissected. Two ganglia (L3-L4) were removed by bipolar electro-coagulation. PMID:17685269

  8. Storage Rings

    SciTech Connect

    Fischer, W.

    2011-01-01

    Storage rings are circular machines that store particle beams at a constant energy. Beams are stored in rings without acceleration for a number of reasons (Tab. 1). Storage rings are used in high-energy, nuclear, atomic, and molecular physics, as well as for experiments in chemistry, material and life sciences. Parameters for storage rings such as particle species, energy, beam intensity, beam size, and store time vary widely depending on the application. The beam must be injected into a storage ring but may not be extracted (Fig. 1). Accelerator rings such as synchrotrons are used as storage rings before and after acceleration. Particles stored in rings include electrons and positrons; muons; protons and anti-protons; neutrons; light and heavy, positive and negative, atomic ions of various charge states; molecular and cluster ions, and neutral polar molecules. Spin polarized beams of electrons, positrons, and protons were stored. The kinetic energy of the stored particles ranges from 10{sup -6} eV to 3.5 x 10{sup 12} eV (LHC, 7 x 10{sup 12} eV planned), the number of stored particles from one (ESR) to 1015 (ISR). To store beam in rings requires bending (dipoles) and transverse focusing (quadrupoles). Higher order multipoles are used to correct chromatic aberrations, to suppress instabilities, and to compensate for nonlinear field errors of dipoles and quadrupoles. Magnetic multipole functions can be combined in magnets. Beams are stored bunched with radio frequency systems, and unbunched. The magnetic lattice and radio frequency system are designed to ensure the stability of transverse and longitudinal motion. New technologies allow for better storage rings. With strong focusing the beam pipe dimensions became much smaller than previously possible. For a given circumference superconducting magnets make higher energies possible, and superconducting radio frequency systems allow for efficient replenishment of synchrotron radiation losses of large current electron or

  9. [Neonatal occlusion due to a lumbar hernia].

    PubMed

    Hunald, F A; Ravololoniaina, T; Rajaonarivony, M F V; Rakotovao, M; Andriamanarivo, M L; Rakoto-Ratsimba, H

    2011-10-01

    A Petit lumbar hernia is an uncommon hernia. Congenital forms are seen in children. Incarceration may occur as an unreducible lumbar mass, associated with bilious vomiting and abdominal distention. Abdominal X-ray shows sided-wall bowel gas. In this case, reduction and primary closure must be performed as emergency repair. PMID:21868206

  10. The lumbar shield: a preliminary report.

    PubMed

    Feild, J R; McHenry, H

    1978-01-01

    Postoperative perineural adhesions between the lumbar nerve root and the partially removed intervertebral disc are thought to be a cause of failure of the standard operative procedure for the removal of a ruptured lumbar intervertebral disc. Attempts have been made to reduce postoperative perineural adhesions by the use of epidural muscle, fat, gelatin sponge, silicone, and steroids. The present communication introduces a new implantable silicone device, a lumbar shield, designed to: (a) provide a radiopaque marker on the dorsal perimeter of the excavated lumbar disc so that the presence or absence of a recurrent disc herniation can easily be determined on plain postoperative x-ray films, (b) provide ready access to the operative site in the event of a recurrent disc herniation, (c) prevent postoperative perineural adhesions between the lumbar dura and the nerve root and the partially removed intervertebral disc, and (d) prevent postoperative adhesions between the lumbar dura and the nerve root and the paraspinal muscles. Satisfactory results of lumbar disc surgery over the past 44 years have occurred in about 90% of routine patients. The value of the lumbar shield in 82 patients (59 routine and 23 workmen's compensation/medicolegal patients) followed for 6 months is described. A satisfactory result, i.e., relief of pain or the presence of occasional postoperative pain, occurred in 85% of routine patients at 1 month, 97% at 3 months, and 95% at 6 months. PMID:683493

  11. Lumbar Epidural Varix Mimicking Disc Herniation

    PubMed Central

    Bursalı, Adem; Guvenal, Ahmet Burak; Yaman, Onur

    2016-01-01

    Lumbar radiculopathy is generally caused by such well-recognized entity as lumbar disc herniation in neurosurgical practice; however rare pathologies such as thrombosed epidural varix may mimic them by causing radicular symptoms. In this case report, we present a 26-year-old man with the complaint of back and right leg pain who was operated for right L4–5 disc herniation. The lesion interpreted as an extruded disc herniation preoperatively was found to be a thrombosed epidural varix compressing the nerve root preoperatively. The nerve root was decompressed by shrinking the lesion with bipolar thermocoagulation and excision. The patient's complaints disappeared in the postoperative period. Thrombosed lumbar epidural varices may mimic lumbar disc herniations both radiologically and clinically. Therefore, must be kept in mind in the differential diagnosis of lumbar disc herniations. Microsurgical techniques are mandatory for the treatment of these pathologies and decompression with thermocoagulation and excision is an efficient method. PMID:27446525

  12. Lumbar Epidural Varix Mimicking Disc Herniation.

    PubMed

    Bursalı, Adem; Akyoldas, Goktug; Guvenal, Ahmet Burak; Yaman, Onur

    2016-07-01

    Lumbar radiculopathy is generally caused by such well-recognized entity as lumbar disc herniation in neurosurgical practice; however rare pathologies such as thrombosed epidural varix may mimic them by causing radicular symptoms. In this case report, we present a 26-year-old man with the complaint of back and right leg pain who was operated for right L4-5 disc herniation. The lesion interpreted as an extruded disc herniation preoperatively was found to be a thrombosed epidural varix compressing the nerve root preoperatively. The nerve root was decompressed by shrinking the lesion with bipolar thermocoagulation and excision. The patient's complaints disappeared in the postoperative period. Thrombosed lumbar epidural varices may mimic lumbar disc herniations both radiologically and clinically. Therefore, must be kept in mind in the differential diagnosis of lumbar disc herniations. Microsurgical techniques are mandatory for the treatment of these pathologies and decompression with thermocoagulation and excision is an efficient method. PMID:27446525

  13. Ring Galaxies

    NASA Astrophysics Data System (ADS)

    Dennefeld, M.; Materne, J.

    1980-09-01

    Among the 338 exotic, intriguing and/or fascinating objects contained in Arp's catalogue of peculiar galaxies, two, Arp 146 and 147, are calling special attention as a presumably separate class of objects displaying closed rings with almost empty interior. It is difficult to find out when, historically speaking, attention was called first to this type of object as a peculiar class, but certainly ga1axies with rings were widely found and recognized in the early sixties, ul}der others by Vorontsov-Velyaminov (1960), Sandage (1961) in the Hubble Atlas or de Vaucouleurs (1964) in the first reference catalogue of ga1axies. The most recent estimates by Arp and Madore (1977) from a search on about 200 Schmidt plates covering 7,000 square degrees give 3.6 per cent of ring galaxies among 2,784 peculiar galaxies found. However, despite the mythological perfection associated with a circle, some ordering is necessary before trying to understand the nature of such objects. This is particularly true because a large fraction of those galaxies with rings are probably normal spiral galaxies of type RS or S(r) as defined by de Vaucouleurs, where the spiral arms are simply "closing the circle". A good example of such "ordinary" galaxy is NGC 3081 in the Hubble Atlas .

  14. Plexiform Schwannoma of Lumbar Region

    PubMed Central

    Parihar, Asmita; Verma, Sarika; Suri, Tarun; Agarwal, Anil; Bansal, Kalpana

    2015-01-01

    Plexiform schwannoma is an unusual peripheral nerve sheath tumor. It can mimic plexiform neurofibroma. A five-year-old girl presented with painful swelling in left lumbar region. Radiologic investigations showed a multinodular tumor in the subcutaneous plane of lumbosacral region. A complete excision and histopathologic examination revealed a plexiform tumor composed of hypocellular and hypercellular areas with verocay bodies. The tumor cells showed strong positivity for S-100 protein, rendering a final diagnosis of plexiform schwannoma. The child has been free of recurrence in 12-month follow-up. PMID:26064806

  15. ISASS Policy Statement – Lumbar Artificial Disc

    PubMed Central

    Garcia, Rolando

    2015-01-01

    Purpose The primary goal of this Policy Statement is to educate patients, physicians, medical providers, reviewers, adjustors, case managers, insurers, and all others involved or affected by insurance coverage decisions regarding lumbar disc replacement surgery. Procedures This Policy Statement was developed by a panel of physicians selected by the Board of Directors of ISASS for their expertise and experience with lumbar TDR. The panel's recommendation was entirely based on the best evidence-based scientific research available regarding the safety and effectiveness of lumbar TDR. PMID:25785243

  16. Lumbar stenosis: clinical case☆☆☆

    PubMed Central

    Sá, Pedro; Marques, Pedro; Alpoim, Bruno; Rodrigues, Elisa; Félix, António; Silva, Luís; Leal, Miguel

    2014-01-01

    Lumbar stenosis is an increasingly common pathological condition that is becoming more frequent with increasing mean life expectancy, with high costs for society. It has many causes, among which degenerative, neoplastic and traumatic causes stand out. Most of the patients respond well to conservative therapy. Surgical treatment is reserved for patients who present symptoms after implementation of conservative measures. Here, a case of severe stenosis of the lumbar spine at several levels, in a female patient with pathological and surgical antecedents in the lumbar spine, is presented. The patient underwent two different decompression techniques within the same operation. PMID:26229836

  17. [Occupation and lumbar disk prolapse].

    PubMed

    Jensen, M V; Tüchsen, F

    1995-03-13

    All Danish occupational groups were screened for an increased risk of hospitalization due to a prolapsed lumbar intervertebral disc (PLID) (ICD-8: 725.11). A cohort of all gainfully employed Danes aged 20 to 59 years in 1981 was followed-up for 10 years for first hospitalization with PLID. A Standardized Hospitalization Ratio was calculated using all economically active persons as the reference group. Male groups with an elevated risk were found in building and construction, the iron and metal industry, in the food and nutrition sector and in occupational driving. Almost all groups of professional drivers had an elevated risk. Female groups with an elevated risk were mainly found in the same industries, but home helps, service workers in the private sector and sewing machine operators also had an elevated risk. We conclude that there are significant and systematic differences between occupational groups as concerns the risk of hospital admission due to PLID. PMID:7725550

  18. Lumbar Epidural Varix Mimicking Perineural Cyst

    PubMed Central

    Pusat, Serhat; Kural, Cahit; Aslanoglu, Atilla; Kurt, Bulent

    2013-01-01

    Lumbar epidural varices are rare and usually mimick lumbar disc herniations. Back pain and radiculopathy are the main symptoms of lumbar epidural varices. Perineural cysts are radiologically different lesions and should not be confused with epidural varix. A 36-year-old male patient presented to us with right leg pain. The magnetic resonance imaging revealed a cystic lesion at S1 level that was compressing the right root, and was interpreted as a perineural cyst. The patient underwent surgery via right L5 and S1 hemilaminectomy, and the lesion was coagulated and removed. The histopathological diagnosis was epidural varix. The patient was clinically improved and the follow-up magnetic resonance imaging showed the absence of the lesion. Lumbar epidural varix should be kept in mind in the differential diagnosis of the cystic lesions which compress the spinal roots. PMID:23741553

  19. Spontaneous resolution of lumbar vertebral eosinophilic granuloma.

    PubMed

    Bavbek, M; Atalay, B; Altinörs, N; Caner, H

    2004-02-01

    Eosinophilic granuloma (EG) is a rare disease but is more common in adults than children. It's often self-limiting. Spinal involvement is rare. It is the localized and most benign form of Langerhans' cell histiocytosis (previously known as histiocytosis X), characterised by lytic lesions in one or more bones. Spontaneous resolution of vertebral body lesions is very rare. In this case, the patient had one EG in a cervical vertebra and a similar lesion in a lumbar vertebra. This case is important because it featured a symptomatic lesion in the cervical spine accompanied by an asymptomatic lesion in a lumbar vertebra. We treated the cervical lesion by surgical fusion and followed the lumbar lesion up conservatively, with the patient in a corset. After 8 years of follow-up, control MRI showed that the lumbar lesion had spontaneously resolved. PMID:14963750

  20. Ringing wormholes

    SciTech Connect

    Konoplya, R.A.; Molina, C.

    2005-06-15

    We investigate the response of traversable wormholes to external perturbations through finding their characteristic frequencies and time-domain profiles. The considered solution describes traversable wormholes between the branes in the two brane Randall-Sundrum model and was previously found within Einstein gravity with a conformally coupled scalar field. The evolution of perturbations of a wormhole is similar to that of a black hole and represents damped oscillations (ringing) at intermediately late times, which are suppressed by power-law tails (proportional to t{sup -2} for monopole perturbations) at asymptotically late times.

  1. Posteroanterior versus anteroposterior lumbar spine radiology

    SciTech Connect

    Tsuno, M.M.; Shu, G.J. )

    1990-03-01

    The posteroanterior view of the lumbar spine has important features including radiation protection and image quality; these have been studied by various investigators. Investigators have shown that sensitive tissues receive less radiation dosage in the posteroanterior view of the spine for scoliosis screening and intracranial tomography without altering the image quality. This paper emphasizes the importance of the radiation safety aspect of the posteroanterior view and shows the improvement in shape distortion in the lumbar vertebrae.

  2. Asystole during lumbar discectomy: a case report.

    PubMed

    Chauhan, Vikas; Tiwari, Ankita; Rath, Girija Prasad; Banik, Sujoy

    2016-06-01

    Hemodynamic derangements have been reported after surgery involving upper cervical spine. Similar observations, however, are rare during a lumbar spine surgery. We share our experience in a patient who had 2 episodes of bradycardia leading to transient asystole while undergoing lumbar discectomy for prolapsed intervertebral disc. The risk of life-threatening hemodynamic disturbances during seemingly uncomplicated surgery in prone position has been emphasized. PMID:27185724

  3. Automatic Lumbar Spondylolisthesis Measurement in CT Images.

    PubMed

    Liao, Shu; Zhan, Yiqiang; Dong, Zhongxing; Yan, Ruyi; Gong, Liyan; Zhou, Xiang Sean; Salganicoff, Marcos; Fei, Jun

    2016-07-01

    Lumbar spondylolisthesis is one of the most common spinal diseases. It is caused by the anterior shift of a lumbar vertebrae relative to subjacent vertebrae. In current clinical practices, staging of spondylolisthesis is often conducted in a qualitative way. Although meyerding grading opens the door to stage spondylolisthesis in a more quantitative way, it relies on the manual measurement, which is time consuming and irreproducible. Thus, an automatic measurement algorithm becomes desirable for spondylolisthesis diagnosis and staging. However, there are two challenges. 1) Accurate detection of the most anterior and posterior points on the superior and inferior surfaces of each lumbar vertebrae. Due to the small size of the vertebrae, slight errors of detection may lead to significant measurement errors, hence, wrong disease stages. 2) Automatic localize and label each lumbar vertebrae is required to provide the semantic meaning of the measurement. It is difficult since different lumbar vertebraes have high similarity of both shape and image appearance. To resolve these challenges, a new auto measurement framework is proposed with two major contributions: First, a learning based spine labeling method that integrates both the image appearance and spine geometry information is designed to detect lumbar vertebrae. Second, a hierarchical method using both the population information from atlases and domain-specific information in the target image is proposed for most anterior and posterior points positioning. Validated on 258 CT spondylolisthesis patients, our method shows very similar results to manual measurements by radiologists and significantly increases the measurement efficiency. PMID:26849859

  4. An update on the management of chronic lumbar discogenic pain.

    PubMed

    Manchikanti, Laxmaiah; Hirsch, Joshua A

    2015-09-01

    Lumbar degenerative disc disease without disc herniation, also known as discogenic pain, is an elusive diagnosis of chronic low back pain. Lumbar provocation discography and fusion surgery have been frequently utilized for several decades as the gold standards for the diagnosis and treatment of symptomatic lumbar discogenic pain, though controversial, based on conjecture, rather than evidence. In addition to lumbar fusion, various other operative and nonoperative modalities of treatments are available in managing chronic lumbar discogenic pain. This review provides an updated assessment of the management of chronic lumbar discogenic pain with a critical look at the many modalities of treatments that are currently available. PMID:26255722

  5. A Comparative Study of Lateral Lumbar Interbody Fusion and Posterior Lumbar Interbody Fusion in Degenerative Lumbar Spondylolisthesis

    PubMed Central

    Hughes, Alexander P.; Sama, Andrew A.; Girardi, Federico P.; Lebl, Darren R.; Cammisa, Frank P.

    2015-01-01

    Study Design Level 4 retrospective review. Purpose To compare the radiographic and clinical outcomes between posterior lumbar interbody fusion (PLIF) and lateral lumbar interbody fusion (LLIF) with posterior segmental spinal instrumentation (SSI) for degenerative lumbar spondylolisthesis. Overview of Literature Both PLIF and LLIF have been performed for degenerative spondylolisthesis with good results, but no study has directly compared these two techniques so far. Methods The electronic medical and radiographic records of 78 matched patients were analyzed. In one group, 39 patients underwent PLIF with SSI at 41 levels (L3-4/L4-5), while in the other group, 39 patients underwent the LLIF procedure at 48 levels (L3-4/L4-5). Radiological outcomes such as restoration of disc height and neuroforaminal height, segmental lumbar lordosis, total lumbar lordosis, incidence of endplate fracture, and subsidence were measured. Perioperative parameters were also recorded in each group. Clinical outcome in both groups was assessed by the short form-12, Oswestry disability index and visual analogue scale scores. The average follow-up period was 16.1 months in the LLIF group and 21 months in the PLIF group. Results The restoration of disc height, foraminal height, and segmental lumbar lordosis was significantly better in the LLIF group (p<0.001). The duration of the operation was similar in both groups, but the average blood loss was significantly lower in the LLIF group (p<0.001). However, clinical outcome scores were similar in both groups. Conclusions Safe, effective interbody fusion can be achieved at multiple levels with neuromonitoring by the lateral approach. LLIF is a viable treatment option in patients with new onset symptoms due to degenerative spondylolisthesis who have had previous lumbar spine surgery, and it results in improved sagittal alignment and indirect foraminal decompression. PMID:26435782

  6. Mucus-secreting 'signet-ring' cells in CSF revealing the site of primary cancer.

    PubMed Central

    Agnelli, G.; Gresele, P.

    1980-01-01

    A case is reported of leptomeningeal carcinomatosis in which identification of mucus-secreting 'signet-ring' carcinoma cells in the CSF allowed diagnosis of an otherwise asymptomatic gastric cancer. When lumbar puncture is performed, careful cytological examination of the CSF should be carried out in any undiagnosed patient with neurological symptoms and signs. Images Fig. 1 Fig. 2 PMID:6267573

  7. 49 CFR 572.85 - Lumbar spine flexure.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... rotate from its initial position in accordance with Figure No. 18 of § 572.21 (49 CFR part 572) by 40... lumbar cable by tightening the adjustment nut for the lumbar vertebrae until the spring is compressed...

  8. 49 CFR 572.85 - Lumbar spine flexure.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... rotate from its initial position in accordance with Figure No. 18 of § 572.21 (49 CFR part 572) by 40... lumbar cable by tightening the adjustment nut for the lumbar vertebrae until the spring is compressed...

  9. 49 CFR 572.85 - Lumbar spine flexure.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... rotate from its initial position in accordance with Figure No. 18 of § 572.21 (49 CFR part 572) by 40... lumbar cable by tightening the adjustment nut for the lumbar vertebrae until the spring is compressed...

  10. 49 CFR 572.85 - Lumbar spine flexure.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... rotate from its initial position in accordance with Figure No. 18 of § 572.21 (49 CFR part 572) by 40... lumbar cable by tightening the adjustment nut for the lumbar vertebrae until the spring is compressed...

  11. Minimally invasive procedures on the lumbar spine.

    PubMed

    Skovrlj, Branko; Gilligan, Jeffrey; Cutler, Holt S; Qureshi, Sheeraz A

    2015-01-16

    Degenerative disease of the lumbar spine is a common and increasingly prevalent condition that is often implicated as the primary reason for chronic low back pain and the leading cause of disability in the western world. Surgical management of lumbar degenerative disease has historically been approached by way of open surgical procedures aimed at decompressing and/or stabilizing the lumbar spine. Advances in technology and surgical instrumentation have led to minimally invasive surgical techniques being developed and increasingly used in the treatment of lumbar degenerative disease. Compared to the traditional open spine surgery, minimally invasive techniques require smaller incisions and decrease approach-related morbidity by avoiding muscle crush injury by self-retaining retractors, preventing the disruption of tendon attachment sites of important muscles at the spinous processes, using known anatomic neurovascular and muscle planes, and minimizing collateral soft-tissue injury by limiting the width of the surgical corridor. The theoretical benefits of minimally invasive surgery over traditional open surgery include reduced blood loss, decreased postoperative pain and narcotics use, shorter hospital length of stay, faster recover and quicker return to work and normal activity. This paper describes the different minimally invasive techniques that are currently available for the treatment of degenerative disease of the lumbar spine. PMID:25610845

  12. A musculoskeletal model for the lumbar spine.

    PubMed

    Christophy, Miguel; Faruk Senan, Nur Adila; Lotz, Jeffrey C; O'Reilly, Oliver M

    2012-01-01

    A new musculoskeletal model for the lumbar spine is described in this paper. This model features a rigid pelvis and sacrum, the five lumbar vertebrae, and a rigid torso consisting of a lumped thoracic spine and ribcage. The motion of the individual lumbar vertebrae was defined as a fraction of the net lumbar movement about the three rotational degrees of freedom: flexion-extension lateral bending, and axial rotation. Additionally, the eight main muscle groups of the lumbar spine were incorporated using 238 muscle fascicles with prescriptions for the parameters in the Hill-type muscle models obtained with the help of an extensive literature survey. The features of the model include the abilities to predict joint reactions, muscle forces, and muscle activation patterns. To illustrate the capabilities of the model and validate its physiological similarity, the model's predictions for the moment arms of the muscles are shown for a range of flexion-extension motions of the lower back. The model uses the OpenSim platform and is freely available on https://www.simtk.org/home/lumbarspine to other spinal researchers interested in analyzing the kinematics of the spine. The model can also be integrated with existing OpenSim models to build more comprehensive models of the human body. PMID:21318374

  13. Percutaneous endoscopic lumbar discectomy - early clinical experience.

    PubMed

    Hirano, Yoshitaka; Mizuno, Junichi; Takeda, Masaaki; Itoh, Yasunobu; Matsuoka, Hidenori; Watanabe, Kazuo

    2012-01-01

    We report our early clinical experience with percutaneous endoscopic lumbar discectomy (PELD) for herniated nucleus pulposus (HNP) in the lumbar spine. We introduced PELD to our clinical practice in June 2009. A total of 311 patients with degenerative lumbar spine disease were treated in our hospital up to August 2011. Thirty-seven patients with lumbar HNP were treated by PELD. PELD was carried out under local anesthesia, and the endoscope was continuously irrigated with saline. Twenty-eight patients were treated through the transforaminal approach, 5 were treated through the interlaminar approach, and 4 were treated through the extraforaminal approach. Surgery was discontinued due to uncontrollable intraoperative pain or anatomical inaccessibility in one case of the interlaminar approach and 2 cases of the extraforaminal approach. In the other 34 patients, the elapsed time of surgery was 34 to 103 minutes (mean 62.4 minutes). Extracorporeal blood loss was insignificant. Immediate symptom relief was achieved in all patients, and postoperative magnetic resonance imaging revealed sufficient removal of the HNP. The length of the postoperative hospital stay was 1 or 2 days in all patients. The surgical method of PELD is completely different from percutaneous nucleotomy, and the aim is to directly remove the HNP with minimum damage to the musculoskeletal structure. Although this study is based on our early clinical outcomes, PELD seemed to be a promising minimally invasive surgery for HNP in the lumbar spine. PMID:23006872

  14. Economic impact of minimally invasive lumbar surgery

    PubMed Central

    Hofstetter, Christoph P; Hofer, Anna S; Wang, Michael Y

    2015-01-01

    Cost effectiveness has been demonstrated for traditional lumbar discectomy, lumbar laminectomy as well as for instrumented and noninstrumented arthrodesis. While emerging evidence suggests that minimally invasive spine surgery reduces morbidity, duration of hospitalization, and accelerates return to activites of daily living, data regarding cost effectiveness of these novel techniques is limited. The current study analyzes all available data on minimally invasive techniques for lumbar discectomy, decompression, short-segment fusion and deformity surgery. In general, minimally invasive spine procedures appear to hold promise in quicker patient recovery times and earlier return to work. Thus, minimally invasive lumbar spine surgery appears to have the potential to be a cost-effective intervention. Moreover, novel less invasive procedures are less destabilizing and may therefore be utilized in certain indications that traditionally required arthrodesis procedures. However, there is a lack of studies analyzing the economic impact of minimally invasive spine surgery. Future studies are necessary to confirm the durability and further define indications for minimally invasive lumbar spine procedures. PMID:25793159

  15. 49 CFR 572.19 - Lumbar spine, abdomen and pelvis.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 7 2014-10-01 2014-10-01 false Lumbar spine, abdomen and pelvis. 572.19 Section 572.19 Transportation Other Regulations Relating to Transportation (Continued) NATIONAL HIGHWAY...-Year-Old Child § 572.19 Lumbar spine, abdomen and pelvis. (a) The lumbar spine, abdomen, and...

  16. 49 CFR 572.19 - Lumbar spine, abdomen and pelvis.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 7 2010-10-01 2010-10-01 false Lumbar spine, abdomen and pelvis. 572.19 Section 572.19 Transportation Other Regulations Relating to Transportation (Continued) NATIONAL HIGHWAY...-Year-Old Child § 572.19 Lumbar spine, abdomen and pelvis. (a) The lumbar spine, abdomen, and...

  17. 49 CFR 572.19 - Lumbar spine, abdomen and pelvis.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 7 2012-10-01 2012-10-01 false Lumbar spine, abdomen and pelvis. 572.19 Section 572.19 Transportation Other Regulations Relating to Transportation (Continued) NATIONAL HIGHWAY...-Year-Old Child § 572.19 Lumbar spine, abdomen and pelvis. (a) The lumbar spine, abdomen, and...

  18. Asymmetric dipolar ring

    DOEpatents

    Prosandeev, Sergey A.; Ponomareva, Inna V.; Kornev, Igor A.; Bellaiche, Laurent M.

    2010-11-16

    A device having a dipolar ring surrounding an interior region that is disposed asymmetrically on the ring. The dipolar ring generates a toroidal moment switchable between at least two stable states by a homogeneous field applied to the dipolar ring in the plane of the ring. The ring may be made of ferroelectric or magnetic material. In the former case, the homogeneous field is an electric field and in the latter case, the homogeneous field is a magnetic field.

  19. Cervical Meningomyelitis After Lumbar Epidural Steroid Injection.

    PubMed

    Lee, Yujin; Kim, Joon-Sung; Kim, Ji Yeon

    2015-06-01

    Epidural steroid injections (ESI) are a common treatment for back pain management. ESI-related complications have increased with the growing number of procedures. We report a case of cervical meningomyelitis followed by multiple lumbar ESI. A 60-year-old male with diabetes mellitus presented to our hospital with severe neck pain. He had a history of multiple lumbar injections from a local pain clinic. After admission, high fever and elevated inflammatory values were detected. L-spine magnetic resonance imaging (MRI) revealed hematoma in the S1 epidural space. Antibiotic treatment began under the diagnosis of a lumbar epidural abscess. Despite the treatment, he started to complain of weakness in both lower extremities. Three days later, the weakness progressed to both upper extremities. C-spine MRI revealed cervical leptomeningeal enhancement in the medulla oblongata and cervical spinal cord. Removal of the epidural abscess was performed, but there was no neurological improvement. PMID:26161360

  20. Use of autologous growth factors in lumbar spinal fusion.

    PubMed

    Lowery, G L; Kulkarni, S; Pennisi, A E

    1999-08-01

    The results of spinal fusion, especially posteriorly above the lumbosacral junction, have been mixed. Autologous growth factor concentrate (AGF) prepared by ultraconcentration of platelets contains multiple growth factors having a chemotactic and mitogenic effect on mesenchymal stem cells and osteoblasts and may play a role in initiating bone healing. The purpose of this retrospective study is to review our results with AGF in lumbar spinal fusions. To date, AGF has been used in 39 patients having lumbar spinal fusion. The study group consisted of the first 19 consecutive cases to allow at least 6 months follow-up. The average follow-up was 13 months (range 6 to 18 months). Follow-up compliance was 91%. There were 7 men and 12 women. Average age was 52 years (range 30-72 years). Nine patients had prior back surgery. There were 8 smokers. AGF was used in posterior (n = 15) or anterior intradiscal (n = 4) fusions. AGF was used with autograft and coraline hydroxyapatite in all posterior fusions, and autograft, coral, and intradiscal spacer (carbon fiber spinal fusion cages or Synthes femoral ring) in intradiscal fusions. Posterior stabilization was used in all cases. Eight cases were single-level fusions, 6 were two-level, and 1 was a three-level fusion. Autologous iliac crest bone graft was taken in 14 cases and local autograft used in 5 cases. Posteriorly, a total of 23 levels were fused; of these, nine were at L5-S1, eight at L4-L5, five at L3-L4, and one at L2-L3. No impending pseudoarthroses were noted on plain radiographic examination at last follow-up visit. Solid fusion was confirmed in 3 patients having routine hardware removal, and in 2 patients who had surgery at an adjacent level. There was one posterior wound infection, which was managed without sequelae. When used as an adjunct to autograft, AGF offers theoretical advantages that need to be examined in controlled studies. Further study is necessary to determine whether coralline hydroxyapatite used as a

  1. [Lumbar disc herniation and andrological diseases].

    PubMed

    Jin, Bao-fang

    2015-10-01

    Lumbar disc herniation is a common male disease. In the past, More academic attention was directed to its relationship with lumbago and leg pain than to its association with andrological diseases. Studies show that central lumber intervertebral disc herniation may cause cauda equina injury and result in premature ejaculation, erectile dysfunction, chronic pelvic pain syndrome, priapism, and emission. This article presents an overview on the correlation between central lumbar intervertebral disc herniation and andrological diseases, focusing on the aspects of etiology, pathology, and clinical progress, hoping to invite more attention from andrological and osteological clinicians. PMID:26665671

  2. Progression of a lumbar disc extrusion.

    PubMed

    Crowell, Michael S; Alitz, Curtis

    2014-11-01

    The patient was a 34-year-old woman who was referred to a physical therapist for a chief complaint of progressively worsening right buttock pain with paresthesias of the right posterior thigh and calf. Prior magnetic resonance imaging of the patient's lumbar spine revealed a large left paracentral disc extrusion at L5-S1. Following physical therapist intervention, the patient reported a new onset of left posterior thigh pain, with paresthesias of the dorsolateral aspect of the left foot. Repeat magnetic resonance imaging of the patient's lumbar spine revealed an increase in the size of the disc extrusion at L5-S1. PMID:25361862

  3. Return to Play After Lumbar Spine Surgery.

    PubMed

    Cook, Ralph W; Hsu, Wellington K

    2016-10-01

    Surgical management of lumbar spine conditions can produce excellent outcomes in athletes. Microdiscectomy for lumbar disc herniation has favorable outcomes; most athletes return to play at preoperative performance levels. Direct pars repair is successful in younger athletes, with high rates of return to play for a variety of fixation techniques. Fusion in athletes with scoliosis is a negative predictor. There are few evidence-based return to play criteria. Athletes should demonstrate full resolution of symptoms and flexibility, endurance, and strength before returning to play. Deciding when to return an athlete to sport depends on particular injury sustained, sport, and individual factors. PMID:27543402

  4. Ligamentum flavum hematoma in the lumbar spine.

    PubMed

    Yamaguchi, Satoshi; Hida, Kazutoshi; Akino, Minoru; Seki, Toshitaka; Yano, Shunsuke; Iwasaki, Yoshinobu

    2005-05-01

    A 62-year-old male presented with a rare case of ligamentum flavum hematoma manifesting as low back pain and gait difficulty beginning 1 month before consulting our institute. He had no history of lumbar spine surgery or lumbar puncture. However, he might have suffered forgotten back injury while practicing martial arts. Magnetic resonance imaging showed a heterogeneous intensity mass lesion with a cystic component at the L3-4 levels. The lesion was totally removed through a hemilaminectomy. Intraoperative and histological findings confirmed the diagnosis of old hematoma with granulomatous change in the ligamentum flavum. Postoperatively, his low back pain and gait difficulty resolved within a few days. PMID:15914970

  5. Mini-open anterior lumbar interbody fusion.

    PubMed

    Gandhoke, Gurpreet S; Ricks, Christian; Tempel, Zachary; Zuckerbraun, Brian; Hamilton, D Kojo; Okonkwo, David O; Kanter, Adam S

    2016-07-01

    In deformity surgery, anterior lumbar interbody fusion provides excellent biomechanical support, creates a broad surface area for arthrodesis, and induces lordosis in the lower lumbar spine. Preoperative MRI, plain radiographs, and, when available, CT scan should be carefully assessed for sacral slope as it relates to pubic symphysis, position of the great vessels (especially at L4/5), disc space height, or contraindication to an anterior approach. This video demonstrates the steps in an anterior surgical procedure with minimal open exposure. The video can be found here: https://youtu.be/r3bC4_vu1hQ . PMID:27364424

  6. Microdiscectomy for a Paracentral Lumbar Herniated Disk.

    PubMed

    Millhouse, Paul W; Schroeder, Gregory D; Kurd, Mark F; Kepler, Christopher K; Vaccaro, Alexander R; Savage, Jason W

    2016-02-01

    Lumbar disk herniations occur frequently and are often associated with leg pain, weakness, and paresthesias. Fortunately, the natural outcomes of radiculopathy due to a disk herniation are generally favorable, and the vast majority of patients improve with nonoperative care. Surgical intervention is reserved for patients who have significant pain that is refractory to at least 6 weeks of conservative care, patients who have a severe or progressive motor deficit, or patients who have any symptoms of bowel or bladder dysfunction. This paper reviews the preoperative and postoperative considerations, as well as the surgical technique, for a microdiscectomy for a lumbar intervertebral disk herniation. PMID:26710186

  7. DEGENERATIVE STENOSIS OF THE LUMBAR SPINE

    PubMed Central

    Zylbersztejn, Sérgio; Spinelli, Leandro de Freitas; Rodrigues, Nilson Rodinei; Werlang, Pablo Mariotti; Kisaki, Yorito; Rios, Aldemar Roberto Mieres; Bello, Cesar Dall

    2015-01-01

    This paper presents an update on degenerative stenosis of the lumbar spine, which is a common pathological condition among patients over the age of 65 years. The anamnesis and physical examination need to be precise, since radiography often only provides indirect signs. Magnetic resonance imaging is necessary if the symptoms persist. The treatment for lumbar stenosis is a matter of controversy. However, there seems to be some benefit from surgical treatment rather than conservative treatment, such that surgery brings improvements in symptoms and functions for a period of up to two years. PMID:27042635

  8. Saturn's Spectacular Ring System

    NASA Technical Reports Server (NTRS)

    Lissauer, Jack J.; DeVincenzi, Donald (Technical Monitor)

    2001-01-01

    Saturn's beautiful rings have fascinated astronomers since they were first observed by Galileo in 1610. The main rings consist of solid particles mostly in the 1 cm - 10 m range, composed primarily of water ice. The ring disk is exceptionally thin - the typical local thickness of the bright rings is tens of meters, whereas the diameter of the main rings is 250,000 km! The main rings exhibit substantial radial variations "ringlets", many of which are actively maintained via gravitational perturbations from Saturn's moons. Exterior to the main rings lie tenuous dust rings, which have little mass but occupy a very large volume of space. This seminar will emphasize the physics of ring-moon interactions, recent advances in our understanding of various aspects of the rings obtained from observations taken during 1995 when the rings appeared edge-on to the Earth and then to the Sun, and observations in subsequent years from HST.

  9. [Relationship between lumbosacral multifidus muscle and lumbar disc herniation].

    PubMed

    Chen, Wei-ye; Wang, Kuan; Yuan, Wei-an; Zhan, Hong-sheng

    2016-06-01

    As a common disease in clinical, the treatment of lumbar disc herniation (LDH) focused on local intervertebral disc, such as surgery and other interventional therapy treatment, but postoperative complications and recurrence rate has been a difficult problem in the field of profession. With the development of spine biomechanics and anatomy, researches on lumbar herniation also increased. Researchers discovered that the incidence and prognosis of LDH were inseparable with local muscle and soft tissue. As the deep paraspinal muscles, multifidus muscle plays an important role to make lumbar stability. Its abnormal function could reduce the stable of lumbar spine, and the chronic lumbar disease could also lead to multifidus muscle atrophy. PMID:27534095

  10. Lateral Lumbar Interbody Fusion: Indications, Outcomes, and Complications.

    PubMed

    Kwon, Brian; Kim, David Hanwuk

    2016-02-01

    Lateral lumbar interbody fusion is a minimally invasive spinal fusion technique that uses the retroperitoneal approach to the anterior spinal column. Mechanical and technical results of the technique compare favorably with those of anterior lumbar interbody fusion in regard to large graft placement, graft volumes, and early initial stability. Lateral lumbar interbody fusion uses the transpsoas approach and traverses near the lumbar plexus. It is not, however, without its unique complications. Groin pain or numbness is well tolerated and often temporary; however, quadriceps palsy can be long-lasting and debilitating. Rarer but serious complications include vascular and visceral injury. Lateral lumbar interbody fusion has been used successfully to treat common degenerative spinal conditions such as spinal instability, stenosis, scoliosis, and degenerative disk disease. While understanding of the lumbar plexus and the technical challenges of the procedure improves, lateral lumbar interbody fusion will continue to provide safe and successful clinical outcomes with less morbidity than traditional procedures. PMID:26803545

  11. Current Status of Lumbar Interbody Fusion for Degenerative Spondylolisthesis

    PubMed Central

    TAKAHASHI, Toshiyuki; HANAKITA, Junya; OHTAKE, Yasufumi; FUNAKOSHI, Yusuke; OICHI, Yuki; KAWAOKA, Taigo; WATANABE, Mizuki

    2016-01-01

    Instrumented lumbar fusion can provide immediate stability and assist in satisfactory arthrodesis in patients who have pain or instability of the lumbar spine. Lumbar adjunctive fusion with decompression is often a good procedure for surgical management of degenerative spondylolisthesis (DS). Among various lumbar fusion techniques, lumbar interbody fusion (LIF) has an advantage in that it maintains favorable lumbar alignment and provides successful fusion with the added effect of indirect decompression. This technique has been widely used and represents an advancement in spinal instrumentation, although the rationale and optimal type of LIF for DS remains controversial. We evaluated the current status and role of LIF in DS treatment, mainly as a means to augment instrumentation. We addressed the basic concept of LIF, its indications, and various types including minimally invasive techniques. It also has acceptable biomechanical features, and offers reconstruction with ideal lumbar alignment. Postsurgical adverse events related to each LIF technique are also addressed. PMID:27169496

  12. Stirling engine piston ring

    DOEpatents

    Howarth, Roy B.

    1983-01-01

    A piston ring design for a Stirling engine wherein the contact pressure between the piston and the cylinder is maintained at a uniform level, independent of engine conditions through a balancing of the pressure exerted upon the ring's surface and thereby allowing the contact pressure on the ring to be predetermined through the use of a preloaded expander ring.

  13. Actin Rings of Power.

    PubMed

    Schwayer, Cornelia; Sikora, Mateusz; Slováková, Jana; Kardos, Roland; Heisenberg, Carl-Philipp

    2016-06-20

    Circular or ring-like actin structures play important roles in various developmental and physiological processes. Commonly, these rings are composed of actin filaments and myosin motors (actomyosin) that, upon activation, trigger ring constriction. Actomyosin ring constriction, in turn, has been implicated in key cellular processes ranging from cytokinesis to wound closure. Non-constricting actin ring-like structures also form at cell-cell contacts, where they exert a stabilizing function. Here, we review recent studies on the formation and function of actin ring-like structures in various morphogenetic processes, shedding light on how those different rings have been adapted to fulfill their specific roles. PMID:27326928

  14. New Dust Belts of Uranus: One Ring, Two Ring, Red Ring, Blue Ring

    SciTech Connect

    de Pater, I; Hammel, H B; Gibbard, S G; Showalter, M R

    2006-02-02

    We compare near-infrared observations of the recently discovered outer rings of Uranus with HST results. We find that the inner ring, R/2003 U 2, is red, whereas the outer ring, R/2003 U 1, is very blue. Blue is an unusual color for rings; Saturn's enigmatic E ring is the only other known example. By analogy to the E ring, R/2003 U 1 is probably produced via impacts into the embedded moon Mab, which apparently orbits at a location where non-gravitational perturbations favor the survival and spreading of sub-micron sized dust. R/2003 U 2 more closely resembles Saturn's G ring.

  15. Footprint mismatch in lumbar total disc arthroplasty.

    PubMed

    Gstoettner, Michaela; Michaela, Gstoettner; Heider, Denise; Denise, Heider; Liebensteiner, Michael; Bach, Christian Michael; Michael, Bach Christian

    2008-11-01

    Lumbar disc arthroplasty has become a popular modality for the treatment of degenerative disc disease. The dimensions of the implants are based on early published geometrical measurements of vertebrae; the majority of these were cadaver studies. The fit of the prosthesis in the intervertebral space is of utmost importance. An undersized implant may lead to subsidence, loosening and biomechanical failure due to an incorrect center of rotation. The aim of the present study was to measure the dimensions of lumbar vertebrae based on CT scans and assess the accuracy of match in currently available lumbar disc prostheses. A total of 240 endplates of 120 vertebrae were included in the study. The sagittal and mediolateral diameter of the upper and lower endplates were measured using a digital measuring system. For the levels L4/L5 and L5/S1, an inappropriate size match was noted in 98.8% (Prodisc L) and 97.6% (Charite) with regard to the anteroposterior diameter. Mismatch in the anterior mediolateral diameter was noted in 79.3% (Prodisc L) and 51.2% (Charite) while mismatch in the posterior mediolateral diameter was observed in 91.5% (Prodisc L) and 78% (Charite) of the endplates. Surgeons and manufacturers should be aware of the size mismatch of currently available lumbar disc prostheses, which may endanger the safety and efficacy of the procedure. Larger footprints of currently available total disc arthroplasties are required. PMID:18791748

  16. Footprint mismatch in lumbar total disc arthroplasty

    PubMed Central

    Michaela, Gstoettner; Denise, Heider; Liebensteiner, Michael

    2008-01-01

    Lumbar disc arthroplasty has become a popular modality for the treatment of degenerative disc disease. The dimensions of the implants are based on early published geometrical measurements of vertebrae; the majority of these were cadaver studies. The fit of the prosthesis in the intervertebral space is of utmost importance. An undersized implant may lead to subsidence, loosening and biomechanical failure due to an incorrect center of rotation. The aim of the present study was to measure the dimensions of lumbar vertebrae based on CT scans and assess the accuracy of match in currently available lumbar disc prostheses. A total of 240 endplates of 120 vertebrae were included in the study. The sagittal and mediolateral diameter of the upper and lower endplates were measured using a digital measuring system. For the levels L4/L5 and L5/S1, an inappropriate size match was noted in 98.8% (Prodisc L) and 97.6% (Charite) with regard to the anteroposterior diameter. Mismatch in the anterior mediolateral diameter was noted in 79.3% (Prodisc L) and 51.2% (Charite) while mismatch in the posterior mediolateral diameter was observed in 91.5% (Prodisc L) and 78% (Charite) of the endplates. Surgeons and manufacturers should be aware of the size mismatch of currently available lumbar disc prostheses, which may endanger the safety and efficacy of the procedure. Larger footprints of currently available total disc arthroplasties are required. PMID:18791748

  17. Partial Facetectomy for Lumbar Foraminal Stenosis

    PubMed Central

    Kang, Kevin; Rodriguez-Olaverri, Juan Carlos; Razi, Afshin; Farcy, Jean Pierre

    2014-01-01

    Background. Several different techniques exist to address the pain and disability caused by isolated nerve root impingement. Failure to adequately decompress the lumbar foramen may lead to failed back surgery syndrome. However, aggressive treatment often causes spinal instability or may require fusion for satisfactory results. We describe a novel technique for decompression of the lumbar nerve root and demonstrate its effectiveness in relief of radicular symptoms. Methods. Partial facetectomy was performed by removal of the medial portion of the superior facet in patients with lumbar foraminal stenosis. 47 patients underwent the procedure from 2001 to 2010. Those who demonstrated neurogenic claudication without spinal instability or central canal stenosis and failed conservative management were eligible for the procedure. Functional level was recorded for each patient. These patients were followed for an average of 3.9 years to evaluate outcomes. Results. 27 of 47 patients (57%) reported no back pain and no functional limitations. Eight of 47 patients (17%) reported moderate pain, but had no limitations. Six of 47 patients (13%) continued to experience degenerative symptoms. Five of 47 patients (11%) required additional surgery. Conclusions. Partial facetectomy is an effective means to decompress the lumbar nerve root foramen without causing spinal instability. PMID:25110591

  18. A hundred years of lumbar puncture.

    PubMed

    Dugacki, V

    1992-01-01

    In the years 1991 and 1992 the 100th anniversary of the announcement of the lumbar puncture method (1891) and 150th anniversary of the birth of its inventor Heinrich Irenaeus Quincke (1842) are celebrated. In the article a short review is given of the development of this method. PMID:1463808

  19. Endoscopic inter laminar management of lumbar disease

    PubMed Central

    Yadav, Yad Ram; Parihar, Vijay; Kher, Yatin; Bhatele, Pushp Raj

    2016-01-01

    Discectomy for lumbar disc provides faster relief in acute attack than does conservative management. Long-term results of open, microscopy-, and endoscopy-assisted discectomy are same. Early results of endoscopy-assisted surgery are better as compared to that of open surgery in terms of better visualization, smaller incision, reduced hospital stay, better education, lower cost, less pain, early return to work, and rehabilitation. Although microscopic discectomy also has comparable advantages, endoscopic-assisted technique better addresses opposite side pathology. Inter laminar technique (ILT) and trans foraminal technique (TFT) are two main endoscopic approaches for lumbar pathologies. Endoscopy-assisted ILT can be performed in recurrent, migrated, and calcified discs. All lumbar levels including L5-S1 level, intracanalicular, foraminal disc, lumbar canal and lateral recess stenosis, multiple levels, and bilateral lesions can be managed by ILT. Migrated, calcified discs, L5-S1 pathology, lumbar canal, and lateral recess stenosis can be better approached by ILT than by TFT. Most spinal surgeons are familiar with anatomy of ILT. It can be safely performed in foramen stenosis and in uncooperative and anxious patients. There is less risk of exiting nerve root damage, especially in short pedicles and in presence of facet osteophytes as compared to TFT. On the other hand, ILT is more invasive than TFT with more chances of perforations of the dura matter, pseudomeningocele formation, and cerebrospinal fluid fistula in early learning curve. Obtaining microsurgical experience, attending workshops, and suitable patient selection can help shorten the learning curve. Once adequate skill is acquired, this procedure is safe and effective. The surgeon must be prepared to convert to an open procedure, especially in early learning curve. Spinal endoscopy is likely to achieve more roles in future. Endoscopy-assisted ILT is a safer alternative to the microscopic technique. PMID

  20. Optimizing Thomson's jumping ring

    NASA Astrophysics Data System (ADS)

    Tjossem, Paul J. H.; Brost, Elizabeth C.

    2011-04-01

    The height to which rings will jump in a Thomson jumping ring apparatus is the central question posed by this popular lecture demonstration. We develop a simple time-averaged inductive-phase-lag model for the dependence of the jump height on the ring material, its mass, and temperature and apply it to measurements of the jump height for a set of rings made by slicing copper and aluminum alloy pipe into varying lengths. The data confirm a peak jump height that grows, narrows, and shifts to smaller optimal mass when the rings are cooled to 77 K. The model explains the ratio of the cooled/warm jump heights for a given ring, the reduction in optimal mass as the ring is cooled, and the shape of the mass resonance. The ring that jumps the highest is found to have a characteristic resistance equal to the inductive reactance of the set of rings.

  1. Jupiter's Main Ring/Ring Halo

    NASA Technical Reports Server (NTRS)

    1997-01-01

    A mosaic of four images taken through the clear filter (610 nanometers) of the solid state imaging (CCD) system aboard NASA's Galileo spacecraft on November 8, 1996, at a resolution of approximately 46 kilometers (28.5 miles) per picture element (pixel) along Jupiter's rings. Because the spacecraft was only about 0.5 degrees above the ring plane, the image is highly foreshortened in the vertical direction. The images were obtained when Galileo was in Jupiter's shadow, peering back toward the Sun; the ring was approximately 2.3 million kilometers (1.4 million miles) away. The arc on the far right of the image is produced when sunlight is scattered by small particles comprising Jupiter's upper atmospheric haze. The ring also efficiently scatters light, indicating that much of its brightness is due to particles that are microns or less in diameter. Such small particles are believed to have human-scale lifetimes, i.e., very brief compared to the solar system's age.

    Jupiter's ring system is composed of three parts - - a flat main ring, a lenticular halo interior to the main ring, and the gossamer ring, outside the main ring. The near and far arms of Jupiter's main ring extend horizontally across the mosaic, joining together at the ring's ansa, on the figure's far left side. The near arm of the ring appears to be abruptly truncated close to the planet, at the point where it passes into Jupiter's shadow. Some radial structure is barely visible across the ring's ansa (top image). A faint mist of particles can be seen above and below the main rings. This vertically extended 'halo' is unusual in planetary rings, and is probably caused by electromagnetic forces pushing the smallest grains out of the ring plane. Because of shadowing, the halo is not visible close to Jupiter in the lower right part of the mosaic. To accentuate faint features in the bottom image of the ring halo, different brightnesses are shown through color. Brightest features are white or yellow and the

  2. On semi ring bornologies

    NASA Astrophysics Data System (ADS)

    Imran, A. N.; Rakhimov, I. S.; Husain, Sh. K. Said

    2016-06-01

    Our main focus in this work is to introduce new structure bornological semi rings. This generalizes the theory of algebraic semi rings from the algebraic setting to the framework of bornological sets. We give basic properties for this new structure. As well as, We study the fundamental construction of bornological semi ring as product, inductive limits and projective limits and their extensions on bornological semi ring. Additionally, we introduce the category of bornological semi rings and study product and pullback (fiber product) in the category of bornological semi rings.

  3. A methodology for quantifying seated lumbar curvatures.

    PubMed

    Leitkam, Samuel T; Bush, Tamara Reid; Li, Mingfei

    2011-11-01

    To understand the role seating plays in the support of posture and spinal articulation, it is necessary to study the interface between a human and the seat. However, a method to quantify lumbar curvature in commercially available unmodified seats does not currently exist. This work sought to determine if the lumbar curvature for normal ranges of seated posture could be documented by using body landmarks located on the anterior portion of the body. The development of such a methodology will allow researchers to evaluate spinal articulation of a seated subject while in standard, commercially available seats and chairs. Anterior measurements of boney landmarks were used to quantify the relative positions of the ribcage and pelvis while simultaneous posterior measurements were made of lumbar curvature. The relationship between the anterior and the posterior measures was compared. The predictive capacity of this approach was evaluated by determining linear and second-order regressions for each of the four postures across all subjects and conducting a leave-one-out cross validation. The relationships between the anterior and posterior measures were approximated by linear and second-order polynomial regressions (r(2 ) =  0.829, 0.935 respectively) across all postures. The quantitative analysis showed that openness had a significant relationship with lumbar curvature, and a first-order regression was superior to a second-order regression. Average standard errors in the prediction were 5.9° for the maximum kyphotic posture, 9.9° for the comfortable posture, 12.8° for the straight and tall, and 22.2° for the maximum lordotic posture. These results show predictions of lumbar curvature are possible in seated postures by using a motion capture system and anterior measures. This method of lumbar curvature prediction shows potential for use in the assessment of seated spinal curvatures and the corresponding design of seating to accommodate those curvatures; however

  4. Lumbar spinal epidural arteriovenous fistula with perimedullary venous drainage after endoscopic lumbar surgery

    PubMed Central

    Murakami, Toshiharu; Wada, Takeshi; Kichikawa, Kimihiko; Nakase, Hiroyuki

    2015-01-01

    Spinal epidural arteriovenous fistulas (AVFs) with perimedullary venous drainage are rare. This report describes a case of lumbar epidural AVF in a patient with a history of endoscopic lumbar discectomy at the same level 8 years prior to presenting with progressive myelopathy secondary to retrograde venous reflux into the perimedullary vein. A 69-year-old man presented with progressive lower extremity weakness and sensory disturbance and loss of sphincter control 8 years after endoscopic lumbar discectomy for a disc herniation at L4–5 level. Magnetic resonance imaging showed spinal cord edema and dilated intradural perimedullary vessels. Spinal angiography revealed an epidural AVF at the site of the previous endoscopic lumbar surgery with intradural perimedullary venous drainage. The fistula was successfully occluded via endovascular transarterial embolization, and the patient had stabilization of his neurological deficits. Lumbar spinal epidural AVFs, especially those associated with iatrogenic trauma, are rare. Endoscopic surgical procedure can occlude the epidural venous plexus and disturb venous drainage, thereby inducing local venous hypertension and leading to epidural AVF with perimedullary venous drainage. This type of pathology should be considered within the differential diagnosis of delayed neurological deterioration after spinal surgery. PMID:25948114

  5. Symptomatic Pneumocephalus after Lumbar Disc Surgery: a Case Report

    PubMed Central

    Kizilay, Zahir; Yilmaz, Ali; Ismailoglu, Ozgur

    2015-01-01

    Symptomatic pneumocephalus is frequently seen after traumatic fracture of the skull base bone. However, it has rarely been reported after spinal surgery and its mechanism has not been fully explained. In this paper, we present a 30 year old male patient who had lumbar discectomy due to a symptomatic midline lumbar disc herniation. He had developed symptomatic pneumocephalus after the lumbar disc surgery associated with application of a vacuum suction device. We present and discuss our patient in the light of the literatures.

  6. New dust belts of Uranus: one ring, two ring, red ring, blue ring.

    PubMed

    de Pater, Imke; Hammel, Heidi B; Gibbard, Seran G; Showalter, Mark R

    2006-04-01

    We compared near-infrared observations of the recently discovered outer rings of Uranus with Hubble Space Telescope results. We find that the inner ring, R/2003 U 2, is red, whereas the outer ring, R/2003 U 1, is very blue. Blue is an unusual color for rings; Saturn's enigmatic E ring is the only other known example. By analogy to the E ring, R/2003 U 1 is probably produced by impacts into the embedded moon Mab, which apparently orbits at a location where nongravitational perturbations favor the survival and spreading of submicron-sized dust. R/2003 U 2 more closely resembles Saturn's G ring, which is red, a typical color for dusty rings. PMID:16601188

  7. Hemophilic pseudotumor of the first lumbar vertebra.

    PubMed

    Nachimuthu, Gurusamy; Arockiaraj, Justin; Krishnan, Venkatesh; Sundararaj, Gabriel David

    2014-11-01

    Hemophilic pseudotumor involving the spine is extremely uncommon and presents a challenging problem. Preoperative planning, angiography, intra and perioperative monitoring with factor VIII cover and postoperative care for hemophilic pseudotumor is vital. Recognition of the artery of Adamkiewicz in the thoracolumbar junction helps to avoid intraoperative neurological injury. We report the case of a 26-year-old male patient with hemophilia A, who presented with a massive pseudotumor involving the first lumbar vertebra and the left iliopsoas. Preoperative angiography revealed the artery of Adamkiewicz arising from the left first lumbar segmental artery. Excision of pseudotumor was successfully carried out with additional spinal stabilization. At 2 years followup, there was no recurrence and the patient was well stabilized with a satisfactory functional status. Surgical excision gives satisfactory outcome in such cases. PMID:25404776

  8. Hemophilic pseudotumor of the first lumbar vertebra

    PubMed Central

    Nachimuthu, Gurusamy; Arockiaraj, Justin; Krishnan, Venkatesh; Sundararaj, Gabriel David

    2014-01-01

    Hemophilic pseudotumor involving the spine is extremely uncommon and presents a challenging problem. Preoperative planning, angiography, intra and perioperative monitoring with factor VIII cover and postoperative care for hemophilic pseudotumor is vital. Recognition of the artery of Adamkiewicz in the thoracolumbar junction helps to avoid intraoperative neurological injury. We report the case of a 26-year-old male patient with hemophilia A, who presented with a massive pseudotumor involving the first lumbar vertebra and the left iliopsoas. Preoperative angiography revealed the artery of Adamkiewicz arising from the left first lumbar segmental artery. Excision of pseudotumor was successfully carried out with additional spinal stabilization. At 2 years followup, there was no recurrence and the patient was well stabilized with a satisfactory functional status. Surgical excision gives satisfactory outcome in such cases. PMID:25404776

  9. [Idiopathic Lumbar Hernia: A Case Report].

    PubMed

    Tsujino, Takuya; Inamoto, Teruo; Matsunaga, Tomohisa; Uchimoto, Taizo; Saito, Kenkichi; Takai, Tomoaki; Minami, Koichiro; Takahara, Kiyoshi; Nomi, Hayahito; Azuma, Haruhito

    2015-11-01

    A 68-year-old woman, complained of an indolent lump about 60 × 70 mm in size in the left lower back. We conducted a computed tomography scan, which exhibited a hernia of Gerota'sfascia-commonly called superior lumbar hernia. In the right lateral position, the hernia contents were observed to attenuate, hence only closure of the hernial orifice was conducted by using Kugel patch, without removal of the hernia sack. Six months after the surgery, she has had no relapse of the hernia. Superior lumbar hernia, which occurs in an anatomically brittle region in the lower back, is a rare and potentially serious disease. The urologic surgeon should bear in mind this rarely seen entity. PMID:26699890

  10. Primary lumbar extradural hemangiosarcoma in a dog.

    PubMed

    Paek, Matthew; Glass, Eric; Kent, Marc; Clifford, Craig A; De Lahunta, Alexander

    2015-01-01

    A 9 yr old castrated male golden retriever weighing 36 kg was presented for evaluation of progressive left pelvic limb paresis and fecal and urinary incontinence. MRI demonstrated an extradural, ovoid mass compressing the lumbar spinal cord. Surgical excision of the mass was performed. Histologically, the mass was consistent with hemangiosarcoma with no involvement of the adjacent vertebrae. The dog underwent a doxorubicin-based chemotherapy protocol with the addition of oral cyclophosphamide. After completion of chemotherapy, the dog was evaluated q 4 mo for restaging. Clinicopathological evidence of primary tumor recurrence or metastatic disease was not detected for 15 mo after initial diagnosis and treatment. To the authors' knowledge, this is the first report of a primary extradural hemangiosarcoma in the lumbar vertebral column in a dog. The clinical presentation, diagnosis, treatment, and outcome are also discussed. PMID:25955146

  11. [Vascular complications associated with lumbar spinal surgery].

    PubMed

    Riedemann-Wistuba, M; Alonso-Pérez, M; Llaneza-Coto, J M

    2016-01-01

    Although there are currently less invasive techniques available for the treatment of spinal injuries, open surgery is still required in many cases. Vascular injuries occurring during lumbar spine surgery, although uncommon, are of great importance due to their potential gravity. Clinical manifestations vary from an acute hemorrhagic shock that needs urgent treatment to save the patient's life, to insidious injuries or an asymptomatic evolution, and should be studied to choose the best therapeutic alternative. Four cases are reported that represent this range of possibilities and emphasize the importance of a careful surgical technique during lumbar spine interventions, and the need for high clinical suspicion, essential for the early diagnosis of these vascular complications. The current therapeutic options are also discussed. PMID:25662569

  12. Intradural herniation of lumbar intervertebral discs.

    PubMed

    Hodge, C J; Binet, E F; Kieffer, S A

    1978-12-01

    A case of intradural rupture of a lumbar intervertebral disc is reported, and the literature is reviewed. The majority of intradural disc herniations occur at the L4--5 level. These patients usually have neurologic deficits more severe than those found in the much more common extradural disc herniations. The myelographic picture varies from an irregularly marginated intradural lesion overlying the disc space to a complete block. The common factor allowing intradural disc herniation is probably dense adhesions between the dura and the posterior longitudinal ligament, preventing the more common lateral extradural disc herniation. Intradural disc herniation should be included in the differential diagnosis of lumbar intradural lesions causing nerve root or cauda equina compression. PMID:741242

  13. Saturn's F-Ring

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This narrow-angle camera image of Saturn's F Ring was taken through the Clear filter while at a distance of 6.9 million km from Saturn on 8 November 1980. The brightness variations of this tightly-constrained ring shown here indicate that the ring is less uniform in makeup than the larger rings. JPL managed the Voyager Project for NASA's Office of Space Science

  14. Neptune - full ring system

    NASA Technical Reports Server (NTRS)

    1989-01-01

    This pair of Voyager 2 images (FDS 11446.21 and 11448.10), two 591-s exposures obtained through the clear filter of the wide angle camera, show the full ring system with the highest sensitivity. Visible in this figure are the bright, narrow N53 and N63 rings, the diffuse N42 ring, and (faintly) the plateau outside of the N53 ring (with its slight brightening near 57,500 km).

  15. Lumbar nerve root: the enigmatic eponyms.

    PubMed

    Dyck, P

    1984-01-01

    Man's quest for recognition has not escaped the physician, whose contributions to medicine perpetuate his name in print. It is a final grasp for professional immortality, which for men like Imhotep and Hippocrates, has prevailed for millennia. This fervor was particularly evident in the latter 19th century, which created a flurry of eponyms, often two or more physicians publishing the same clinical observation. This article reviews the eponym epidemic as it relates to lumbar radiculopathy. PMID:6372123

  16. Weightlifter Lumbar Physiology Health Influence Factor Analysis of Sports Medicine

    PubMed Central

    Zhang, Xiangyang

    2015-01-01

    Chinese women's weightlifting project has been in the advanced world level, suggests that the Chinese coaches and athletes have many successful experience in the weight lifting training. Little weight lifting belongs to high-risk sports, however, to the lumbar spine injury, some young good athletes often due to lumbar trauma had to retire, and the national investment and athletes toil is regret things. This article from the perspective of sports medicine, weightlifting athletes training situation analysis and put forward Suggestions, aimed at avoiding lumbar injury, guarantee the health of athletes. In this paper, first of all to 50 professional women's weightlifting athletes doing investigation, found that 82% of the athletes suffer from lumbar disease symptoms, the reason is mainly composed of lumbar strain, intensity is too large, motion error caused by three factors. From the Angle of sports medicine and combined with the characteristics of the structure of human body skeleton athletes lumbar structural mechanics analysis, find out the lumbar force's two biggest technical movement, study, and regulate the action standard, so as to minimize lumbar force, for athletes to contribute to the health of the lumbar spine. PMID:26981162

  17. Design concepts in lumbar total disc arthroplasty

    PubMed Central

    Bellini, Chiara M.; Zweig, Thomas; Ferguson, Stephen; Raimondi, Manuela T.; Lamartina, Claudio; Brayda-Bruno, Marco; Fornari, Maurizio

    2008-01-01

    The implantation of lumbar disc prostheses based on different design concepts is widely accepted. This paper reviews currently available literature studies on the biomechanics of TDA in the lumbar spine, and is targeted at the evaluation of possible relationships between the aims of TDA and the geometrical, mechanical and material properties of the various available disc prostheses. Both theoretical and experimental studies were analyzed, by a PUBMED search (performed in February 2007, revised in January 2008), focusing on single level TDA. Both semi-constrained and unconstrained lumbar discs seem to be able to restore nearly physiological IAR locations and ROM values. However, both increased and decreased ROM was stated in some papers, unrelated to the clinical outcome. Segmental lordosis alterations after TDA were reported in most cases, for both constrained and unconstrained disc prostheses. An increase in the load through the facet joints was documented, for both semi-constrained and unconstrained artificial discs, but with some contrasting results. Semi-constrained devices may be able to share a greater part of the load, thus protecting the surrounding biological structure from overloading and possible early degeneration, but may be more susceptible to wear. The next level of development will be the biomechanical integration of compression across the motion segment. All these findings need to be supported by long-term clinical outcome studies. PMID:18946684

  18. Linear Lumbar Localized Lysis of Elastic Fibers

    PubMed Central

    Tschen, Jaime A.

    2013-01-01

    Background: The absence or loss of elastic fibers in the skin is referred to as dermal elastolysis. Purpose: This paper describes a woman with a distinctive clinical presentation of mid-dermal elastolysis characterized morphologically by multiple horizontal raised bands on the lower back. Methods: A 20-year-old Filipino woman presented with multiple asymptomatic, flesh-colored, raised, firm, linear, cord-like bands on the lumbar area of her back. There were neither similar lesions elsewhere nor a family member with this condition. Results: Microscopic examination of the raised band showed nearly complete absence of elastic fibers in the mid dermis. In contrast, a biopsy of symmetrically located normal-appearing skin showed a uniform distribution of elastic fibers throughout the dermis. Linear lumbar localized elastolysis is a descriptive designation that accurately reflects a correlation of the clinical and pathological changes of this condition. Conclusion: The clinical differential of raised horizontal cord-like bands on the lower back (without a family history of an inherited elastic fiber disorder, a prior history of trauma, or a significant change in weight or exercise habit) includes linear focal elastosis and linear lumbar localized elastolysis. Microscopic evaluation of a Verhoeff-van Gieson stained lesion specimen (which may be accompanied by a biopsy of normal-appearing skin for comparison) will readily differentiate these conditions. The former is usually characterized by increased elastic fibers, whereas the latter, as in this patient, shows a paucity or absence of elastic fibers in the mid dermis. PMID:23882313

  19. The Jumping Ring Experiment

    ERIC Educational Resources Information Center

    Baylie, M.; Ford, P. J.; Mathlin, G. P.; Palmer, C.

    2009-01-01

    The jumping ring experiment has become central to liquid nitrogen shows given as part of the outreach and open day activities carried out within the University of Bath. The basic principles of the experiment are described as well as the effect of changing the geometry of the rings and their metallurgical state. In general, aluminium rings are…

  20. Saturn's F-Ring

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This narrow-angle camera image of Saturn's F Ring was taken through the Clear filter while at a distance of 0.75 million km from Saturn on 12 November 1980. The kinks and braids of this tightly-constrained ring are visible along with the outer edge of the A Ring. JPL managed the Voyager Project for NASA's Office of Space Science.

  1. Rings Around Uranus

    ERIC Educational Resources Information Center

    Maran, Stephen P.

    1977-01-01

    Events leading up to the discovery of the rings of Uranus are described. The methods used and the logic behind the methods are explained. Data collected to prove the existence of the rings are outlined and theories concerning the presence of planetary rings are presented. (AJ)

  2. Lumbar discal cyst with spontaneous regression and subsequent occurrence of lumbar disc herniation.

    PubMed

    Takeshima, Yasuhiro; Takahashi, Toshiyuki; Hanakita, Junya; Watanabe, Mizuki; Kitahama, Yoshihiro; Kuraishi, Keita; Uesaka, Toshio; Minami, Manabu; Nakase, Hiroyuki

    2011-01-01

    A 39-year-old man presented with an extremely rare discal cyst at the L3-4 level manifesting as a left L4 radiculopathy. Two months after onset, he suffered right L4 radiculopathy with new lumbar disc protrusion. Five months after medical treatment, the patient's symptoms improved, and the discal cyst showed complete regression on magnetic resonance imaging. Most cases of discal cyst are surgically treated, with only two previous cases of spontaneous regression. The present case suggests clinical and radiological recovery of symptomatic lumbar discal cyst can be obtained by only conservative therapy. PMID:22123489

  3. MRI Evaluation of Lumbar Disc Degenerative Disease

    PubMed Central

    Patel, Rupal; Mehta, Chetan; Patel, Narrotam

    2015-01-01

    Introduction: Lower back pain secondary to degenerative disc disease is a condition that affects young to middle-aged persons with peak incidence at approximately 40 y. MRI is the standard imaging modality for detecting disc pathology due to its advantage of lack of radiation, multiplanar imaging capability, excellent spinal soft-tissue contrast and precise localization of intervertebral discs changes. Aims and Objective: To evaluate the characterization, extent, and changes associated with the degenerative lumbar disc disease by Magnetic Resonance Imaging. Study Design: Cross-sectional and observational study. Materials and Methods: A total 109 patients of the lumbar disc degeneration with age group between 17 to 80 y were diagnosed & studied on 1.5 Tesla Magnetic Resonance Imaging machine. MRI findings like lumbar lordosis, Schmorl’s nodes, decreased disc height, disc annular tear, disc herniation, disc bulge, disc protrusion and disc extrusion were observed. Narrowing of the spinal canal, lateral recess and neural foramen with compression of nerve roots observed. Ligamentum flavum thickening and facetal arthropathy was observed. Result: Males were more commonly affected in Degenerative Spinal Disease & most of the patients show loss of lumbar lordosis. Decreased disc height was common at L5-S1 level. More than one disc involvement was seen per person. L4 – L5 disc was the most commonly involved. Annular disc tear, disc herniation, disc extrusion, narrowing of spinal canal, narrowing of lateral recess, compression of neural foramen, ligamentum flavum thickening and facetal arthropathy was common at the L4 –L5 disc level. Disc buldge was common at L3 – L4 & L4 – L5 disc level. Posterior osteophytes are common at L3 - L4 & L5 –S1 disc level. L1- L2 disc involvement and spondylolisthesis are less common. Conclusion: Lumbar disc degeneration is the most common cause of low back pain. Plain radiograph can be helpful in visualizing gross anatomic changes in

  4. Lumbar disk herniation surgery: outcome and predictors.

    PubMed

    Sedighi, Mahsa; Haghnegahdar, Ali

    2014-12-01

    Study Design A retrospective cohort study. Objectives To determine the outcome and any differences in the clinical results of three different surgical methods for lumbar disk herniation and to assess the effect of factors that could predict the outcome of surgery. Methods We evaluated 148 patients who had operations for lumbar disk herniation from March 2006 to March 2011 using three different surgical techniques (laminectomy, microscopically assisted percutaneous nucleotomy, and spinous process osteotomy) by using Japanese Orthopaedic Association (JOA) Back Pain Evaluation Questionnaire, Resumption of Activities of Daily Living scale and changes of visual analog scale (VAS) for low back pain and radicular pain. Our study questionnaire addressed patient subjective satisfaction with the operation, residual complaints, and job resumption. Data were analyzed with SPSS version 16.0 (SPSS, Inc., Chicago, Illinois, United States). Statistical significance was set at 0.05. For statistical analysis, chi-square test, Mann-Whitney U test, Kruskal-Wallis test, and repeated measure analysis were performed. For determining the confounding factors, univariate analysis by chi-square test was used and followed by logistic regression analysis. Results Ninety-four percent of our patients were satisfied with the results of their surgeries. VAS documented an overall 93.3% success rate for reduction of radicular pain. Laminectomy resulted in better outcome in terms of JOA Back Pain Evaluation Questionnaire. The outcome of surgery did not significantly differ by age, sex, level of education, preoperative VAS for back, preoperative VAS for radicular pain, return to previous job, or level of herniation. Conclusion Surgery for lumbar disk herniation is effective in reducing radicular pain (93.4%). All three surgical approaches resulted in significant decrease in preoperative radicular pain and low back pain, but intergroup variation in the outcome was not achieved. As indicated

  5. Jovian Ring System Mosaic

    NASA Technical Reports Server (NTRS)

    2000-01-01

    NASA's Galileo spacecraft acquired this mosaic of Jupiter's ring system (top) when the spacecraft was in Jupiter's shadow looking back toward the Sun. Jupiter's ring system (inset diagram) is composed of three parts: an outermost gossamer ring, a flat main ring, and an innermost donut-shaped halo. These rings are made up of dust-sized particles that are blasted off of the nearby inner satellites by small impacts. This image was taken on November 9, 1996 at a distance of 2.3 million kilometers (1.4 million miles).

  6. Saturn's largest ring.

    PubMed

    Verbiscer, Anne J; Skrutskie, Michael F; Hamilton, Douglas P

    2009-10-22

    Most planetary rings in the Solar System lie within a few radii of their host body, because at these distances gravitational accelerations inhibit satellite formation. The best known exceptions are Jupiter's gossamer rings and Saturn's E ring, broad sheets of dust that extend outward until they fade from view at five to ten planetary radii. Source satellites continuously supply the dust, which is subsequently lost in collisions or by radial transport. Here we report that Saturn has an enormous ring associated with its outer moon Phoebe, extending from at least 128R(S) to 207R(S) (Saturn's radius R(S) is 60,330 km). The ring's vertical thickness of 40R(S) matches the range of vertical motion of Phoebe along its orbit. Dynamical considerations argue that these ring particles span the Saturnian system from the main rings to the edges of interplanetary space. The ring's normal optical depth of approximately 2 x 10(-8) is comparable to that of Jupiter's faintest gossamer ring, although its particle number density is several hundred times smaller. Repeated impacts on Phoebe, from both interplanetary and circumplanetary particle populations, probably keep the ring populated with material. Ring particles smaller than centimetres in size slowly migrate inward and many of them ultimately strike the dark leading face of Iapetus. PMID:19812546

  7. Dust and Planetary Rings

    NASA Astrophysics Data System (ADS)

    Siddiqui, Muddassir

    ABSTRACT Space is not empty it has comic radiations (CMBR), dust etc. Cosmic dust is that type of dust which is composed of particles in space which vary from few molecules to 0.1micro metres in size. This type of dust is made up of heavier atoms born in the heart of stars and supernova. Mainly it contains dust grains and when these dust grains starts compacting then it turns to dense clouds, planetary ring dust and circumstellar dust. Dust grains are mainly silicate particles. Dust plays a major role in our solar system, for example in zodiacal light, Saturn's B ring spokes, planetary rings at Jovian planets and comets. Observations and measurements of cosmic dust in different regions of universe provide an important insight into the Universe's recycling processes. Astronomers consider dust in its most recycled state. Cosmic dust have radiative properties by which they can be detected. Cosmic dusts are classified as intergalactic dusts, interstellar dusts and planetary rings. A planetary ring is a ring of cosmic dust and other small particles orbiting around a planet in flat disc shape. All of the Jovian planets in our solar system have rings. But the most notable one is the Saturn's ring which is the brightest one. In March 2008 a report suggested that the Saturn's moon Rhea may have its own tenuous ring system. The ring swirling around Saturn consists of chunks of ice and dust. Most rings were thought to be unstable and to dissipate over course of tens or hundreds of millions of years but it now appears that Saturn's rings might be older than that. The dust particles in the ring collide with each other and are subjected to forces other than gravity of its own planet. Such collisions and extra forces tend to spread out the rings. Pluto is not known to have any ring system but some Astronomers believe that New Horizons probe might find a ring system when it visits in 2015.It is also predicted that Phobos, a moon of Mars will break up and form into a planetary ring

  8. [Dorso-lumbar pain caused by a schmorl hernia].

    PubMed

    Esteban Navarro, Pedro Luis; García Casas, Oscar; Girvent Montllor, Francesc

    2008-09-01

    Thoracic and lumbar spine conditions cause primarily mechanical back pain, although the clinician has to ensure that the symptoms are not from another etiology. We present the case of a patient with thoracic and lumbar non mechanical pain, resistant to treatment, diagnosed with a herniation of the intervertebral disc through the vertebral end-plate. We also performed a literature review. PMID:21794532

  9. The Robotic Lumbar Spine: Dynamics and Feedback Linearization Control

    PubMed Central

    Karadogan, Ernur; Williams, Robert L.

    2013-01-01

    The robotic lumbar spine (RLS) is a 15 degree-of-freedom, fully cable-actuated robotic lumbar spine which can mimic in vivo human lumbar spine movements to provide better hands-on training for medical students. The design incorporates five active lumbar vertebrae and the sacrum, with dimensions of an average adult human spine. It is actuated by 20 cables connected to electric motors. Every vertebra is connected to the neighboring vertebrae by spherical joints. Medical schools can benefit from a tool, system, or method that will help instructors train students and assess their tactile proficiency throughout their education. The robotic lumbar spine has the potential to satisfy these needs in palpatory diagnosis. Medical students will be given the opportunity to examine their own patient that can be programmed with many dysfunctions related to the lumbar spine before they start their professional lives as doctors. The robotic lumbar spine can be used to teach and test medical students in their capacity to be able to recognize normal and abnormal movement patterns of the human lumbar spine under flexion-extension, lateral bending, and axial torsion. This paper presents the dynamics and nonlinear control of the RLS. A new approach to solve for positive and nonzero cable tensions that are also continuous in time is introduced. PMID:24151527

  10. 49 CFR 572.19 - Lumbar spine, abdomen and pelvis.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 7 2013-10-01 2013-10-01 false Lumbar spine, abdomen and pelvis. 572.19 Section 572.19 Transportation Other Regulations Relating to Transportation (Continued) NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) ANTHROPOMORPHIC TEST DEVICES 3-Year-Old Child § 572.19 Lumbar spine, abdomen...

  11. 49 CFR 572.19 - Lumbar spine, abdomen and pelvis.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 7 2011-10-01 2011-10-01 false Lumbar spine, abdomen and pelvis. 572.19 Section 572.19 Transportation Other Regulations Relating to Transportation (Continued) NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) ANTHROPOMORPHIC TEST DEVICES 3-Year-Old Child § 572.19 Lumbar spine, abdomen...

  12. Traceable Ring Signature

    NASA Astrophysics Data System (ADS)

    Fujisaki, Eiichiro; Suzuki, Koutarou

    The ring signature allows a signer to leak secrets anonymously, without the risk of identity escrow. At the same time, the ring signature provides great flexibility: No group manager, no special setup, and the dynamics of group choice. The ring signature is, however, vulnerable to malicious or irresponsible signers in some applications, because of its anonymity. In this paper, we propose a traceable ring signature scheme. A traceable ring scheme is a ring signature except that it can restrict “excessive” anonymity. The traceable ring signature has a tag that consists of a list of ring members and an issue that refers to, for instance, a social affair or an election. A ring member can make any signed but anonymous opinion regarding the issue, but only once (per tag). If the member submits another signed opinion, possibly pretending to be another person who supports the first opinion, the identity of the member is immediately revealed. If the member submits the same opinion, for instance, voting “yes” regarding the same issue twice, everyone can see that these two are linked. The traceable ring signature can suit to many applications, such as an anonymous voting on a BBS. We formalize the security definitions for this primitive and show an efficient and simple construction in the random oracle model.

  13. Sunset on Saturn's Rings

    NASA Technical Reports Server (NTRS)

    1996-01-01

    This is a rare view of Saturn's rings seen just after the Sun has set below the ring plane, taken with the Hubble Space Telescope on Nov. 21, 1995.

    This perspective is unusual because the Earth is slightly above (2.7 degrees latitude) Saturn's rings and the Sun is below them. Normally we see the rings fully illuminated by the Sun.

    The photograph shows three bright ring features: the F Ring, the Cassini Division, and the C Ring (moving from the outer rings to the inner). The low concentration of material in these rings allows light from the Sun to shine through them. The A and B rings are much denser, which limits the amount of light that penetrates through them. Instead, they are faintly visible because they reflect light from Saturn's disk.

    Scientists believe that the F Ring is slightly warped because it disappears part way around on the right (West) side. Hubble's high resolution shows the that A Ring's shadow obscures part of the F ring (right).

    The image was assembled from 20 exposures taken with Wide Field Planetary Camera-2 over 8 hours.

    The Wide Field/Planetary Camera 2 was developed by the Jet Propulsion Laboratory and managed by the Goddard Spaced Flight Center for NASA's Office of Space Science.

    This image and other images and data received from the Hubble Space Telescope are posted on the World Wide Web on the Space Telescope Science Institute home page at URL http://oposite.stsci.edu/pubinfo/

  14. Transforaminal Lumbar Interbody Fusion for Management of Recurrent Lumbar Disc Herniation

    PubMed Central

    2016-01-01

    Study Design Retrospective study. Purpose To study the surgical outcome of transforaminal lumbar interbody fusion (TLIF) combined with trans-pedicular screws fixation for management of selected cases of recurrent lumbar disc herniation. Overview of Literature Recurrent lumbar disc herniation is a major cause of surgical failure, occurring in 5%–11% of cases. The optimal technique for treatment is controversial. Some authors believe that repeated simple discectomy is the treatment of choice, but approach-related complications can be considerable. Other surgeons prefer more removal of posterior elements (as lamina and facet joints) with posterior fusion. Methods The study included 15 patients who presented with symptomatic recurrent lumbar disc herniation who underwent reoperation through posterior trans-pedicular screws and TLIF in our department from April 2008 to May 2010, with a 24-month follow-up. Japanese Orthopedic Association Scale (JOA) was used for low back pain. The results of surgery were also evaluated with the MacNab classification. Results The mean JOA score showed significant improvement, increasing from 9.5 before surgery to 24.0 at the end of follow-up (p<0.001). Clinical outcome was excellent in 7 patients (46% of cases), good in 6 patients (40%) and fair in only 2 patients (14%). There was a significant difference (p<0.05) between patients presenting with recurrent disc at the ipsilateral side and those at the contralateral side. Conclusions In spite of the small number of patients and the short follow-up period, the good clinical and radiological outcome achieved in this study encourage the belief that TLIF is an effective option for the treatment of selected cases of recurrent lumbar disc herniation. PMID:26949458

  15. Provocation Lumbar Diskography at Previously Fused Levels

    PubMed Central

    Dulai, H.S.; Bartynski, W.S.; Rothfus, W.S.; Gerszten, P.C.

    2010-01-01

    Summary Recurrent or persistent low back pain (LBP) after lumbar fusion can be related to many factors. We reviewed the provocation lumbar diskogram (PLD) features and redo-fusion outcome in our patients evaluated for recurrent/persistent LBP after technically successful fusion. LD was performed in 27 patients with recurrent/persistent LBP after prior successful lumbar surgical fusion (31 fused levels: single-level fusion-23; two-level fusion-4). PLD response and imaging characteristics at fused and non-fused levels were assessed including: intra-diskal lidocaine response, diskogram-image/post-diskogram CT appearance, presence/absence of diskographic contrast leakage, and evidence of fusion integrity or hardware failure. Outcomes in patients having redo-fusion were assessed. Concordant pain was encountered at 15 out of 23 (65%) single-level fusions, non-concordant pain in one fusion with non-painful response in seven. Adjacent-level concordant pain was identified in seven out of 23 (30%) patients (three of 15 with painful fused levels; four of seven with non-painful fusions). In two-level fusions, concordant pain was encountered at one fused level in each patient. In painful fused levels, leaking and contained disks were encountered with partial or complete pain elimination after intra-diskal lidocaine injection. In anterior fusions, space or contrast surrounding the cage was noted at five of 11 levels. Pseudoarthrosis was noted only with trans-sacral screw fusions. Redo-fusion in 13 patients resulted in significant improvement in nine and moderate improvement in one. Patients with recurrent/persistent LBP after technically successful fusion may have a diskogenic pain source at the surgically fused or adjacent level confirmed by lidocaine-assisted PLD. PMID:20977869

  16. Chemoembolization for Hepatocellular Carcinoma Supplied by a Lumbar Artery

    SciTech Connect

    Kim, Han Myun; Kim, Hyo-Cheol Woo, Sungmin; Son, Kyu Ri; Cho, Seong Whi; Chung, Jin Wook

    2015-02-15

    PurposeTo describe the radiologic findings and imaging response of hepatocellular carcinoma (HCC) supplied by the lumbar artery.MethodsBetween April 2004 and December 2012, we encountered HCC supplied by a lumbar artery in 21 patients. Two investigators retrospectively reviewed clinical and radiological findings of HCC supplied by the lumbar artery using computed tomography (CT) scans and digital subtraction angiograms.ResultsPatients had received 1–27 sessions of previous chemoembolization procedures (mean 7.7 sessions, median 4 sessions). Mean tumor size was 5.3 cm. The locations of HCC supplied by lumbar artery were the bare area (n = 14, 67 %) and segment VI (n = 7, 33 %). Tumor-feeding arteries arose from the main lumbar artery (n = 7), proximal anterior division (n = 4), and distal anterior division (n = 14). In 20 patients, selective chemoembolization through the tumor-feeding arteries of the lumbar artery was achieved. In 1 patient, nonselective embolization at the main lumbar artery was performed. There was no complication such as skin necrosis or paralysis. On the first follow-up enhanced CT scan, target tumors fed by the lumbar artery showed complete response (n = 6), partial response (n = 4), stable disease (n = 3), and progressive disease (n = 8), but overall tumor response was partial response (n = 1) and progressive disease (n = 20).ConclusionWhen HCC is located in the inferior tip or bare area of the liver, a lumbar artery may supply the tumor. Although selective chemoembolization via the tumor-feeding vessel of the lumbar artery can be achieved in most cases, overall tumor response is commonly unfavorable.

  17. Establishment of a new animal model for ischemic lumbar vertebrae

    PubMed Central

    Hou, Changlong; Tan, Guosheng; Zhuang, Wenquan; Yang, Jianyong

    2015-01-01

    Degeneration and ischemia of lumbar intervertebral disc has become a more and more important issue for elder people. However the mechanism for this is still known, largely due to a lack of a suitable animal model. In this study, we constructed a new animal model for the study of ischemic lumbar vertebrae. 42 New Zealand white rabbits were chosen for the study. For each rabbit, two vertebrae were used. L5 was set as the experimental group and L4 was set as the control group. Percutaneous lumbar puncture needles were applied in vertebrae adjacent to endplate for L5 and L4. For L4 1 ml saline was injected and for L5 1 ml pingyangmycin (2 mg/mL) was used. 1, 2, 3, 4, 5 weeks; 2 and 3 months after surgery, 6 rabbits at each time point were randomly chosen and underwent MRI, pathological test. The results in L5 and L4 were compared. Another 6 rabbits were used for DSA (Digital Subtraction Angiography) and vascular cast to study the length and diameters of the branches of lumbar artery. It was identified that since the third week, slightly hyperintense signal on T2-weighted image (T2WI) and fat-suppression T2-weighted image (FS T2WI) were detected. Lumbar vertebrae damage could be identified since the fourth week. Results of MRI and the size of pathological area were positively related (r=0.965, P<0.05). DSA and vascular cast could both clearly show the third level branches of lumbar artery. Our study suggested that injection of pingyangmycin via percutaneous lumbar needle could successfully induce ischemia in lumbar endplate. This method had little trauma, required a simple operation process and is highly repetitive. Besides, by vascular cast, the most important source of blood supply is the media branch of the lumbar artery. This branch could be a new therapy pathway for the degeneration of lumbar vertebrae. PMID:26379856

  18. [Ischemic optic neuropathy after lumbar spine surgery].

    PubMed

    Bermejo-Alvarez, M A; Carpintero, M; García-Carro, G; Acebal, G; Fervienza, P; Cosío, F

    2007-12-01

    Ischemic optic neuropathy is the most common cause of visual complications after non-ophthalmic surgery. The incidence has varied in different case series, but prone-position spine surgery appears to be involved in most of the reports. We present the case of a 47-year-old woman who developed near total blindness in the left eye following lumbar spine fusion surgery involving the loss of 900 mL of blood. An ophthalmic examination including inspection of the ocular fundus, fluorescein angiography, and visual evoked potentials returned a diagnosis of retrolaminar optic neuropathy. Outcome was poor. PMID:18200998

  19. Minimally Invasive Transforaminal Lumbar Interbody Fusion.

    PubMed

    Ahn, Junyoung; Tabaraee, Ehsan; Singh, Kern

    2015-07-01

    Minimally invasive transforaminal lumbar interbody fusion (MIS TLIF) is performed via tubular dilators thereby preserving the integrity of the paraspinal musculature. The decreased soft tissue disruption in the MIS technique has been associated with significantly decreased blood loss, shorter length of hospitalization, and an expedited return to work while maintaining comparable arthrodesis rates when compared with the open technique particularly in the setting of spondylolisthesis (isthmic and degenerative), recurrent symptomatic disk herniation, spinal stenosis, pseudoarthrosis, iatrogenic instability, and spinal trauma. The purpose of this article and the accompanying video wass to demonstrate the techniques for a primary, single-level MIS TLIF. PMID:26079840

  20. Radioactive gold ring dermatitis

    SciTech Connect

    Miller, R.A.; Aldrich, J.E. )

    1990-08-01

    A superficial squamous cell carcinoma developed in a woman who wore a radioactive gold ring for more than 30 years. Only part of the ring was radioactive. Radiation dose measurements indicated that the dose to basal skin layer was 2.4 Gy (240 rad) per week. If it is assumed that the woman continually wore her wedding ring for 37 years since purchase, she would have received a maximum dose of approximately 4600 Gy.

  1. Features in Saturn's rings

    NASA Technical Reports Server (NTRS)

    Esposito, Larry W.; Harris, Craig C.; Simmons, Karen E.

    1987-01-01

    A systematic, uniform search of Voyage 2 photopolarimeter system (PSS) data set for all significant features of Saturn's rings is described. On August 25, 1981, the PSS observed the occultation of the star Delta Scorpii by the rings of Saturn, and the timing of the data taking was rapid enough that the spatial resolution in the radial direction in the ring plane was better than 100 m. Tabular information and figures for 216 significant features that were found are presented.

  2. Viscosity in Saturn's rings

    NASA Technical Reports Server (NTRS)

    Lissauer, J. J.; Shu, F. H.; Cuzzi, J. N.

    1982-01-01

    The technique of estimating the viscosity in Saturn's rings from the damping rate of waves observed to be propagating within the rings is discussed. The wavetrains of attempts using spiral density waves as a diagnostic suffer significant complications that compromise the interpretations. A method that considers the damping of spiral bending waves was used to deduce a kinematic viscosity of 260 (+150, -100) sqcm/sec for the middle of the A ring where bending waves are excited by the 5:3 vertical resonance with Mimas. This value implies upper limits on the particle velocity dispersion and local ring thickness of 0.4 cm/sec and 30 m, respectively.

  3. Jupiter's Ring Halo

    NASA Technical Reports Server (NTRS)

    1997-01-01

    A mosaic of four images taken through the clear filter (610 nanometers) of the solid state imaging (CCD) system aboard NASA's Galileo spacecraft on November 8, 1996, at a resolution of approximately 46 kilometers (km) per picture element (pixel) along the rings; however, because the spacecraft was only about 0.5 degrees above the ring plane, the image is highly foreshortened in the vertical direction. The images were obtained when Galileo was in Jupiter's shadow peering back toward the Sun; the ring was approximately 2,300,000 kilometers (km) away. The arc on the far right of the image is produced by sunlight scattered by small particles comprising Jupiter's upper atmospheric haze. The ring also efficiently scatters light, indicating that much of its brightness is due to particles that are microns or less in diameter. Such small particles are believed to have human-scale lifetimes, i.e., very brief compared to the solar system's age.

    Jupiter's ring system is composed of three parts -- a flat main ring, a lenticular halo interior to the main ring, and the gossamer ring, which lies exterior to the main ring. The near and far arms of Jupiter's main ring extend horizontally across the mosaic, joining together at the ring's ansa, on the far left side of the figure. The near arm of the ring appears to be abruptly truncated close to the planet, at the point where it passes into Jupiter's shadow.

    A faint mist of particles can be seen above and below the main rings; this vertically extended, toroidal 'halo' is unusual in planetary rings, and is probably caused by electromagnetic forces which can push small grains out of the ring plane. Halo material is present across this entire image, implying that it reaches more than 27,000 km above the ring plane. Because of shadowing, the halo is not visible close to Jupiter in the lower right part of the mosaic. In order to accentuate faint features in the image, different brightnesses are shown through color, with the brightest

  4. Integrated semiconductor ring lasers

    NASA Astrophysics Data System (ADS)

    Jezierski, A. F.; Laybourn, P. J. R.

    1988-02-01

    Ring-waveguide and pill-box structures down to 12 microns in diameter, made in GaAs/GaAlAs heterostructure material, have been designed with output stripe waveguides coupled to the rings via Y-junctions. The waveguides were defined by reactive ion etching, although the inner boundaries of some of the ring waveguides relied on stress and carrier confinement. Lasing has been observed with pulsed drive current, and has been shown to correspond to resonances in the rings, although other resonances have been observed in some of the structures. This type of structure is suitable for use as a light source in monolithic integrated optics.

  5. Ring Around a Galaxy

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Space Telescope Science Institute astronomers are giving the public chances to decide where to aim NASA's Hubble Space Telescope. Guided by 8,000 Internet voters, Hubble has already been used to take a close-up, multi-color picture of the most popular object from a list of candidates, the extraordinary 'polar-ring' galaxy NGC 4650A. Located about 130 million light-years away, NGC 4650A is one of only 100 known polar-ring galaxies. Their unusual disk-ring structure is not yet understood fully. One possibility is that polar rings are the remnants of colossal collisions between two galaxies sometime in the distant past, probably at least 1 billion years ago. What is left of one galaxy has become the rotating inner disk of old red stars in the center. Meanwhile, another smaller galaxy which ventured too close was probably severely damaged or destroyed. The bright bluish clumps, which are especially prominent in the outer parts of the ring, are regions containing luminous young stars, examples of stellar rebirth from the remnants of an ancient galactic disaster. The polar ring appears to be highly distorted. No regular spiral pattern stands out in the main part of the ring, and the presence of young stars below the main ring on one side and above on the other shows that the ring is warped and does not lie in one plane. Determining the typical ages of the stars in the polar ring is an initial goal of our Polar Ring Science Team that can provide a clue to the evolution of this unusual galaxy. The HST exposures were acquired by the Hubble Heritage Team, consisting of Keith Noll, Howard Bond, Carol Christian, Jayanne English, Lisa Frattare, Forrest Hamilton, Anne Kinney and Zolt Levay, and guest collaborators Jay Gallagher (University of Wisconsin-Madison), Lynn Matthews (National Radio Astronomy Observatory-Charlottesville), and Linda Sparke (University of Wisconsin-Madison).

  6. Sacral Insufficiency Fractures Mimicking Lumbar Spine Pathology

    PubMed Central

    K. L., Kalra; Acharya, Shankar; Chahal, Rupinder

    2016-01-01

    Sacral insufficiency fractures (SIFs) are a common cause of back pain in the elderly. SIFs mimic the symptoms of lumbar spine pathology and so are commonly missed or underdiagnosed. Here we present four cases of missed SIFs that were subsequently identified and treated. One patient was treated as mechanical lower back ache, another patient underwent root block and two patients underwent surgery for lumbar canal stenosis. None experienced relief of their symptoms after these procedures. Retrospective analysis of X-ray and magnetic resonance imaging data revealed SIFs that were confirmed by computed tomography scans. All four patients were treated for underlying osteoporosis. Two patients who underwent surgery were treated conservatively and other two were treated by sacroplasty involving injection of cement into the fracture. Sacroplasty produced immediate pain relief and early mobilization compared to the conservative group. SIFs should always be considered in the differential diagnosis of an elderly patient presenting with low back symptoms. Sacroplasty can be considered for immediate pain relief and rapid mobilization. PMID:27340538

  7. Collateral Adverse Outcomes After Lumbar Spine Surgery.

    PubMed

    Daniels, Alan H; Gundle, Kenneth; Hart, Robert A

    2016-01-01

    Collateral adverse outcomes are the expected or unavoidable results of a procedure that is performed in a standard manner and typically experienced by the patient. Collateral adverse outcomes do not result from errors, nor are they rare. Collateral adverse outcomes occur as the direct result of a surgical procedure and must be accepted as a trade-off to attain the intended benefits of the surgical procedure. As such, collateral adverse outcomes do not fit into the traditional definition of a complication or adverse event. Examples of collateral adverse outcomes after lumbar spine arthrodesis include lumbar stiffness, postoperative psychological stress, postoperative pain, peri-incisional numbness, paraspinal muscle denervation, and adjacent-level degeneration. Ideally, a comparison of interventions for the treatment of a clinical condition should include information on both the negative consequences (expected and unexpected) and potential benefits of the treatment options. The objective evaluation and reporting of collateral adverse outcomes will provide surgeons with a more complete picture of invasive interventions and, thus, the improved ability to assess alternative treatment options. PMID:27049197

  8. General versus epidural anesthesia for lumbar microdiscectomy.

    PubMed

    Ulutas, Murat; Secer, Mehmet; Taskapilioglu, Ozgur; Karadas, Soner; Akyilmaz, Ahmet Aykut; Baydilek, Yunus; Kocamer, Betul; Ozboz, Ayse; Boyaci, Suat

    2015-08-01

    This study was a retrospective analysis of 850 lumbar microdiscectomy (LMD) under epidural anesthesia (EA; n=573) or general anesthesia (GA; n=277) performed by the same surgeon and paid by invoice to the Social Security Institution of the Turkish Republic between April 2003 and May 2013. Although GA is the most frequently used method of anesthesia during LMD, the choice of regional anesthetia (epidural, spinal or a combination of these) differs between surgeons and anesthetists. Studies have reported that EA in surgery for lumbar disc herniation may be more reliable than GA, as it enables the surgeon to communicate with the patient during surgery, but few studies have compared the costs of these two anesthetic methods in LMD. We found that EA patient costs were significantly lower than GA patient costs (p<0.01) and there was a statistically significant difference between the two groups in terms of the time spent in the operating room (p<0.01). There was no difference in the duration of surgery (p>0.05). The anesthetic method used during LMD affected the complication rate, cost and efficiency of operating room use. We suggest that EA is an anesthetic method that can contribute to health care cost savings and enable LMD to be completed with less nerve root manipulation and more comfort, efficacy, reliability and cost efficiency without affecting the success rate of the surgical procedure. PMID:26067543

  9. Sacral Insufficiency Fractures Mimicking Lumbar Spine Pathology.

    PubMed

    Sudhir, G; K L, Kalra; Acharya, Shankar; Chahal, Rupinder

    2016-06-01

    Sacral insufficiency fractures (SIFs) are a common cause of back pain in the elderly. SIFs mimic the symptoms of lumbar spine pathology and so are commonly missed or underdiagnosed. Here we present four cases of missed SIFs that were subsequently identified and treated. One patient was treated as mechanical lower back ache, another patient underwent root block and two patients underwent surgery for lumbar canal stenosis. None experienced relief of their symptoms after these procedures. Retrospective analysis of X-ray and magnetic resonance imaging data revealed SIFs that were confirmed by computed tomography scans. All four patients were treated for underlying osteoporosis. Two patients who underwent surgery were treated conservatively and other two were treated by sacroplasty involving injection of cement into the fracture. Sacroplasty produced immediate pain relief and early mobilization compared to the conservative group. SIFs should always be considered in the differential diagnosis of an elderly patient presenting with low back symptoms. Sacroplasty can be considered for immediate pain relief and rapid mobilization. PMID:27340538

  10. Operative Management of Lumbar Degenerative Disc Disease

    PubMed Central

    Lee, Yu Chao; Osti, Orso Lorenzo

    2016-01-01

    Lumbar degenerative disc disease is extremely common. Current evidence supports surgery in carefully selected patients who have failed non-operative treatment and do not exhibit any substantial psychosocial overlay. Fusion surgery employing the correct grafting and stabilization techniques has long-term results demonstrating successful clinical outcomes. However, the best approach for fusion remains debatable. There is some evidence supporting the more complex, technically demanding and higher risk interbody fusion techniques for the younger, active patients or patients with a higher risk of non-union. Lumbar disc arthroplasty and hybrid techniques are still relatively novel procedures despite promising short-term and mid-term outcomes. Long-term studies demonstrating superiority over fusion are required before these techniques may be recommended to replace fusion as the gold standard. Novel stem cell approaches combined with tissue engineering therapies continue to be developed in expectation of improving clinical outcomes. Results with appropriate follow-up are not yet available to indicate if such techniques are safe, cost-effective and reliable in the long-term. PMID:27559465

  11. Operative Management of Lumbar Degenerative Disc Disease.

    PubMed

    Lee, Yu Chao; Zotti, Mario Giuseppe Tedesco; Osti, Orso Lorenzo

    2016-08-01

    Lumbar degenerative disc disease is extremely common. Current evidence supports surgery in carefully selected patients who have failed non-operative treatment and do not exhibit any substantial psychosocial overlay. Fusion surgery employing the correct grafting and stabilization techniques has long-term results demonstrating successful clinical outcomes. However, the best approach for fusion remains debatable. There is some evidence supporting the more complex, technically demanding and higher risk interbody fusion techniques for the younger, active patients or patients with a higher risk of non-union. Lumbar disc arthroplasty and hybrid techniques are still relatively novel procedures despite promising short-term and mid-term outcomes. Long-term studies demonstrating superiority over fusion are required before these techniques may be recommended to replace fusion as the gold standard. Novel stem cell approaches combined with tissue engineering therapies continue to be developed in expectation of improving clinical outcomes. Results with appropriate follow-up are not yet available to indicate if such techniques are safe, cost-effective and reliable in the long-term. PMID:27559465

  12. Spinaplasty following lumbar laminectomy for multilevel lumbar spinal stenosis to prevent iatrogenic instability

    PubMed Central

    Tuli, Surendra Mohan; Kapoor, Varun; Jain, Anil K; Jain, Saurabh

    2011-01-01

    Background: Iatrogenic instability following laminectomy occurs in patients with degenerative lumbar canal stenosis. Long segment fusions to obviate postoperative instability result in loss of motion of lumbar spine and predisposes to adjacent level degeneration. The best alternative would be an adequate decompressive laminectomy with a nonfusion technique of preserving the posterior ligament complex integrity. We report a retrospective analysis of multilevel lumbar canal stenosis that were operated for posterior decompression and underwent spinaplasty to preserve posterior ligament complex integrity for outcome of decompression and iatrogenic instability. Materials and Methods: 610 patients of degenerative lumbar canal stenosis (n=520) and development spinal canal stenosis (n=90), with a mean age 58 years (33–85 years), underwent multilevel laminectomies and spinaplasty procedure. At followup, changes in the posture while walking, increase in the walking distance, improvement in the dysesthesia in lower limb, the motor power, capability to negotiate stairs and sphincter function were assessed. Forward excursion of vertebrae more than 4 mm in flexion–extension lateral X-ray of the spine as compared to the preoperative movements was considered as the iatrogenic instability. Clinical assessment was done in standing posture regarding active flexion–extension movement, lateral bending and rotations Results: All patients were followed up from 3 to 10 years. None of the patients had neurological deterioration or pain or catch while movement. Walking distance improved by 5–10 times, with marked relief (70–90%) in neurogenic claudication and preoperative stooping posture, with improvement in sensation and motor power. There was no significant difference in the sagittal alignment as well as anterior translation. Two patients with concomitant scoliosis and one with cauda equine syndrome had incomplete recovery. Two patients who developed disc protrusion, underwent

  13. Morphological structure and variations of lumbar plexus in human fetuses.

    PubMed

    Yasar, Soner; Kaya, Serdar; Temiz, Cağlar; Tehli, Ozkan; Kural, Cahit; Izci, Yusuf

    2014-04-01

    The objective of this study is to study the anatomy of lumbar plexus on human fetuses and to establish its morphometric characteristics and differences compared with adults. Twenty lumbar plexus of 10 human fetal cadavers in different gestational ages and genders were dissected. Lumbar spinal nerves, ganglions, and peripheral nerves were exposed. Normal anatomical structure and variations of lumbar plexus were investigated and morphometric analyses were performed. The diameters of lumbar spinal nerves increased from L1 to L4. The thickest nerve forming the plexus was femoral nerve, the thinnest was ilioinguinal nerve, the longest nerve through posterior abdominal wall was iliohypogastric nerve, and the shortest nerve was femoral nerve. Each plexus had a single furcal nerve and this arose from L4 nerve in all fetuses. No prefix or postfix plexus variation was observed. In two plexuses, L1 nerve was in the form of a single branch. Also, in two plexuses, genitofemoral nerve arose only from L2 nerve. Accessory obturator nerve was observed in four plexuses. According to these findings, the morphological pattern of the lumbar plexus in the fetus was found to be very similar to the lumbar plexus in adults. PMID:22696243

  14. Instrumented Posterior Lumbar Interbody Fusion in Adult Spondylolisthesis

    PubMed Central

    Yu, Ching-Hsiao; Wang, Chen-Ti

    2008-01-01

    It is unclear whether using artificial cages increases fusion rates compared with use of bone chips alone in posterior lumbar interbody fusion for patients with lumbar spondylolisthesis. We hypothesized artificial cages for posterior lumbar interbody fusion would provide better clinical and radiographic outcomes than bone chips alone. We assumed solid fusion would provide good clinical outcomes. We clinically and radiographically followed 34 patients with spondylolisthesis having posterior lumbar interbody fusion with mixed autogenous and allogeneic bone chips alone and 42 patients having posterior lumbar interbody fusion with implantation of artificial cages packed with morselized bone graft. Patients with the artificial cage had better functional improvement in the Oswestry disability index than those with bone chips alone, whereas pain score, patient satisfaction, and fusion rate were similar in the two groups. Postoperative disc height ratio, slip ratio, and segmental lordosis all decreased at final followup in the patients with bone chips alone but remained unchanged in the artificial cage group. The functional outcome correlated with radiographic fusion status. We conclude artificial cages provide better functional outcomes and radiographic improvement than bone chips alone in posterior lumbar interbody fusion for lumbar spondylolisthesis, although both techniques achieved comparable fusion rates. Level of Evidence: Level III, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence. PMID:18846411

  15. Adverse Event Recording and Reporting in Clinical Trials Comparing Lumbar Disk Replacement with Lumbar Fusion: A Systematic Review

    PubMed Central

    Hiratzka, Jayme; Rastegar, Farbod; Contag, Alec G.; Norvell, Daniel C.; Anderson, Paul A.; Hart, Robert A.

    2015-01-01

    Study Design Systematic review. Objectives (1) To compare the quality of adverse event (AE) methodology and reporting among randomized trials comparing lumbar fusion with lumbar total disk replacement (TDR) using established AE reporting systems; (2) to compare the AEs and reoperations of lumbar spinal fusion with those from lumbar TDR; (3) to make recommendations on how to report AEs in randomized controlled trials (RCTs) so that surgeons and patients have more-detailed and comprehensive information when making treatment decisions. Methods A systematic search of PubMed, the Cochrane collaboration database, and the National Guideline Clearinghouse through May 2015 was conducted. Randomized controlled trials with at least 2 years of follow-up comparing lumbar artificial disk replacement with lumbar fusion were included. Patients were required to have axial or mechanical low back pain of ≥3 months' duration due to degenerative joint disease defined as degenerative disk disease, facet joint disease, or spondylosis. Outcomes included the quality of AE acquisition methodology and results reporting, and AEs were defined as those secondary to the procedure and reoperations. Individual and pooled relative risks and their 95% confidence intervals comparing lumbar TDR with fusion were calculated. Results RCTs demonstrated a generally poor description of methods for assessing AEs. There was a consistent lack of clear definition or grading for these events. Furthermore, there was a high degree of variation in reporting of surgery-related AEs. Most studies lacked adequate reporting of the timing of AEs, and there were no clear distinctions between acute or chronic AEs. Meta-analysis of the pooled data demonstrated a twofold increased risk of AEs in patients having lumbar fusion compared with patients having lumbar TDR at 2-year follow-up, and this relative risk was maintained at 5 years. Furthermore, the pooled data demonstrated a 1.7 times greater relative risk of

  16. Adverse Event Recording and Reporting in Clinical Trials Comparing Lumbar Disk Replacement with Lumbar Fusion: A Systematic Review.

    PubMed

    Hiratzka, Jayme; Rastegar, Farbod; Contag, Alec G; Norvell, Daniel C; Anderson, Paul A; Hart, Robert A

    2015-12-01

    Study Design Systematic review. Objectives (1) To compare the quality of adverse event (AE) methodology and reporting among randomized trials comparing lumbar fusion with lumbar total disk replacement (TDR) using established AE reporting systems; (2) to compare the AEs and reoperations of lumbar spinal fusion with those from lumbar TDR; (3) to make recommendations on how to report AEs in randomized controlled trials (RCTs) so that surgeons and patients have more-detailed and comprehensive information when making treatment decisions. Methods A systematic search of PubMed, the Cochrane collaboration database, and the National Guideline Clearinghouse through May 2015 was conducted. Randomized controlled trials with at least 2 years of follow-up comparing lumbar artificial disk replacement with lumbar fusion were included. Patients were required to have axial or mechanical low back pain of ≥3 months' duration due to degenerative joint disease defined as degenerative disk disease, facet joint disease, or spondylosis. Outcomes included the quality of AE acquisition methodology and results reporting, and AEs were defined as those secondary to the procedure and reoperations. Individual and pooled relative risks and their 95% confidence intervals comparing lumbar TDR with fusion were calculated. Results RCTs demonstrated a generally poor description of methods for assessing AEs. There was a consistent lack of clear definition or grading for these events. Furthermore, there was a high degree of variation in reporting of surgery-related AEs. Most studies lacked adequate reporting of the timing of AEs, and there were no clear distinctions between acute or chronic AEs. Meta-analysis of the pooled data demonstrated a twofold increased risk of AEs in patients having lumbar fusion compared with patients having lumbar TDR at 2-year follow-up, and this relative risk was maintained at 5 years. Furthermore, the pooled data demonstrated a 1.7 times greater relative risk of

  17. EBT ring physics

    SciTech Connect

    Uckan, N.A.

    1980-04-01

    This workshop attempted to evaluate the status of the current experimental and theoretical understanding of hot electron ring properties. The dominant physical processes that influence ring formation, scaling, and their optimal behavior are also studied. Separate abstracts were prepared for each of the 27 included papers. (MOW)

  18. Smoke Ring Physics

    ERIC Educational Resources Information Center

    Huggins, Elisha

    2011-01-01

    The behavior of smoke rings, tornados, and quantized vortex rings in superfluid helium has many features in common. These features can be described by the same mathematics we use when introducing Ampere's law in an introductory physics course. We discuss these common features. (Contains 7 figures.)

  19. Illustration of Saturn's Rings

    NASA Technical Reports Server (NTRS)

    2001-01-01

    This illustration shows a close-up of Saturn's rings. These rings are thought to have formed from material that was unable to form into a Moon because of tidal forces from Saturn, or from a Moon that was broken up by Saturn's tidal forces.

  20. Lower esophageal ring (Schatzki)

    MedlinePlus

    ... narrowed area to stretch the ring. Sometimes, a balloon is placed in the area and inflated, to help widen the ring. Outlook (Prognosis) Swallowing problems may return. You may need repeat treatment. When to Contact a Medical Professional Call your health care provider if you ...

  1. The Fermilab recycler ring

    SciTech Connect

    Martin Hu

    2001-07-24

    The Fermilab Recycler is a permanent magnet storage ring for the accumulation of antiprotons from the Antiproton Source, and the recovery and cooling of the antiprotons remaining at the end of a Tevatron store. It is an integral part of the Fermilab III luminosity upgrade. The following paper describes the design features, operational and commissioning status of the Recycler Ring.

  2. Contactless Magnetic Slip Ring

    NASA Technical Reports Server (NTRS)

    Kumagai, Hiroyuki (Inventor); Deardon, Joe D. (Inventor)

    1997-01-01

    A contactless magnetic slip ring is disclosed having a primary coil and a secondary coil. The primary and secondary coils are preferably magnetically coupled together, in a highly reliable efficient manner, by a magnetic layered core. One of the secondary and primary coils is rotatable and the contactless magnetic slip ring provides a substantially constant output.

  3. Telemetry carrier ring and support

    NASA Technical Reports Server (NTRS)

    Wakeman, Thomas G. (Inventor)

    1992-01-01

    A telemetry carrier ring for use in a gas turbine engine includes an annular support ring connected to the engine and an annular carrier ring coupled to the support ring, each ring exhibiting different growth characteristics in response to thermal and mechanical loading. The carrier ring is coupled to the support ring by a plurality of circumferentially spaced web members which are relatively thin in an engine radial direction to provide a predetermined degree of radial flexibility. the web members have a circumferential width and straight axial line of action selected to transfer torque and thrust between the support ring and the carrier ring without substantial deflection. The use of the web members with radial flexibility provides compensation between the support ring and the carrier ring since the carrier ring grows at a different rate than the supporting ring.

  4. Jupiter's Gossamer Rings Explained.

    NASA Astrophysics Data System (ADS)

    Hamilton, D. P.

    2003-05-01

    Over the past several years, Galileo measurements and groundbased imaging have drastically improved our knowledge of Jupiter's faint ring system. We now recognize that the ring consists of four components: a main ring 7000km wide, whose inner edge blossoms into a vertically-extended halo, and a pair of more tenuous Gossamer rings, one associated with each of the small moons Thebe and Amalthea. When viewed edge on, the Gossamer rings appear as diaphanous disks whose thicknesses agree with the vertical excursions of the inclined satellites from the equatorial plane. In addition, the brightness of each Gossamer ring drops off sharply outside the satellite orbits. These correlations allowed Burns etal (1999, Science, 284, 1146) to argue convincingly that the satellites act as sources of the dusty ring material. In addition, since most material is seen inside the orbits of the source satellites, an inwardly-acting dissipative force such as Poynting-Robertson drag is implicated. The most serious problem with this simple and elegant picture is that it is unable to explain the existence of a faint swath of material that extends half a jovian radius outward from Thebe. A key constraint is that this material has the same thickness as the rest of the Thebe ring. In this work, we identify the mechanism responsible for the outward extension: it is a shadow resonance, first investigated by Horanyi and Burns (1991, JGR, 96, 19283). When a dust grain enters Jupiter's shadow, photoelectric processes shut down and the grain's electric charge becomes more negative. The electromagnetic forces associated with the varying charge cause periodic oscillations in the orbital eccentricity and semimajor axis as the orbital pericenter precesses. This results in a ring which spreads both inward and outward of its source satellite while preserving its vertical thickness - just as is observed for the Thebe ring. Predictions of the model are: i) gaps of micron-sized material interior to Thebe and

  5. Jupiter's Rings: Sharpest View

    NASA Technical Reports Server (NTRS)

    2007-01-01

    The New Horizons spacecraft took the best images of Jupiter's charcoal-black rings as it approached and then looked back at Jupiter. The top image was taken on approach, showing three well-defined lanes of gravel- to boulder-sized material composing the bulk of the rings, as well as lesser amounts of material between the rings. New Horizons snapped the lower image after it had passed Jupiter on February 28, 2007, and looked back in a direction toward the sun. The image is sharply focused, though it appears fuzzy due to the cloud of dust-sized particles enveloping the rings. The dust is brightly illuminated in the same way the dust on a dirty windshield lights up when you drive toward a 'low' sun. The narrow rings are confined in their orbits by small 'shepherding' moons.

  6. STEEL TRUSS TENSION RING SUPPORTING DOME ROOF. TENSION RING COVERED ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    STEEL TRUSS TENSION RING SUPPORTING DOME ROOF. TENSION RING COVERED BY ARCHITECTURAL FINISH. TENSION RING ROLLER SUPPORT AT COLUMN OBSCURED BY COLUMN COVERINGS. - Houston Astrodome, 8400 Kirby Drive, Houston, Harris County, TX

  7. Influence Of Lumbar Spine Kinematics On Feet Pressure Distribution

    NASA Astrophysics Data System (ADS)

    Săftescu-Jescu, C.; Bereteu, L.

    2012-12-01

    Determining the center of pressure trajectories, as an indicator of postural stability or lumbar pathology, has been a challenging issue for researchers during the last decades. The paper advances an investigational method in order to determine a correlation between lumbar spine movements and feet center of pressure distribution. Five young healthy volunteers were simultaneously tested using an ultrasound based motion analyzing system and a force platform, while performing imposed tasks. Results showed specific patterns described by the center of pressure trajectories and a good coordination of angular amplitudes during lumbar spine movement.

  8. A global CT to US registration of the lumbar spine

    NASA Astrophysics Data System (ADS)

    Nagpal, Simrin; Hacihaliloglu, Ilker; Ungi, Tamas; Rasoulian, Abtin; Osborn, Jill; Lessoway, Victoria A.; Rohling, Robert N.; Borschneck, Daniel P.; Abolmaesumi, Purang; Mousavi, Parvin

    2014-03-01

    During percutaneous lumbar spine needle interventions, alignment of the preoperative computed tomography (CT) with intraoperative ultrasound (US) can augment anatomical visualization for the clinician. We propose an approach to rigidly align CT and US data of the lumbar spine. The approach involves an intensity-based volume registration step, followed by a surface segmentation and a point-based registration of the entire lumbar spine volume. A clinical feasibility study resulted in mean registration error of approximately 3 mm between CT and US data.

  9. Clinicoradiological Images of a Rare Type of Lumbar Hernia.

    PubMed

    Agarwal, Arjun; Mukherjee, Sujoy; Garg, Cheena

    2015-12-01

    A surgeon will rarely see a case of lumbar hernia in his lifetime. They are usually divided into superior and inferior types, but in cases of huge hernias where anatomical delineation is not possible, they are called as diffuse. Further classification into primary and secondary types (on the basis of etiology) and congenital and acquired types is done. Evisceration in a lumbar hernia can be present due to secondary causes but never spontaneously. This is therefore probably the first reported case of a primary eviscerated diffuse lumbar hernia. PMID:26884669

  10. The lumbar interspinous bursae and Baastrup's syndrome. An autopsy study.

    PubMed

    Bywaters, E G; Evans, S

    1982-01-01

    This study describes the prevalence, distribution, pathology and pathogenesis of lumbar interspinous bursitis (described as a clinical syndrome by Baastrup in 1933). It is based on an anatomic study of 152 lumbar spines derived from routine and random postmortem material, together with selected specimens from autopsies on patients with various rheumatic diseases. From a statistical study of 50 randomly chosen spines, bursae are found when the interspinous distance is small compared with the total height of the lumbar spine ('bursal index'): nearly all bursal spaces show some sign of inflammation and a few show severe bony erosion. Crystal deposits therein are also described. PMID:7178764

  11. The effects of gluteus muscle strengthening exercise and lumbar stabilization exercise on lumbar muscle strength and balance in chronic low back pain patients

    PubMed Central

    Jeong, Ui-Cheol; Sim, Jae-Heon; Kim, Cheol-Yong; Hwang-Bo, Gak; Nam, Chan-Woo

    2015-01-01

    [Purpose] The aim of this study was to examine the effects of exercise to strengthen the muscles of the hip together with lumbar segmental stabilization exercise on the lumbar disability index, lumbar muscle strength, and balance. [Subjects and Methods] This study randomly and equally assigned 40 participants who provided written consent to participate in this study to a lumbar segmental stabilization exercise plus exercise to strengthen the muscles of the gluteus group (SMG + LES group) and a lumbar segmental stabilization exercise group. [Results] Each evaluation item showed a statistically significant effect. [Conclusion] Clinical application of exercise in this study showed that lumbar segmental stabilization exercise plus exercise to strengthen the muscles of the gluteus resulted in a greater decrease in low back pain disability index and increase in lumbar muscle strength and balance ability than lumbar segmental stabilization exercise in chronic low back pain patients receiving the exercise treatments during the same period. PMID:26834359

  12. Comparison of the Dynesys Dynamic Stabilization System and Posterior Lumbar Interbody Fusion for Lumbar Degenerative Disease

    PubMed Central

    Zhang, Yang; Shan, Jian-Lin; Liu, Xiu-Mei; Li, Fang; Guan, Kai; Sun, Tian-Sheng

    2016-01-01

    Background There have been few studies comparing the clinical and radiographic outcomes between the Dynesys dynamic stabilization system and posterior lumbar interbody fusion (PLIF). The objective of this study is to compare the clinical and radiographic outcomes of Dynesys and PLIF for lumbar degenerative disease. Methods Of 96 patients with lumbar degenerative disease included in this retrospectively analysis, 46 were treated with the Dynesys system and 50 underwent PLIF from July 2008 to March 2011. Clinical and radiographic outcomes were evaluated. We also evaluated the occurrence of radiographic and symptomatic adjacent segment degeneration (ASD). Results The mean follow-up time in the Dynesys group was 53.6 ± 5.3 months, while that in the PLIF group was 55.2 ± 6.8 months. At the final follow-up, the Oswestry disability index and visual analogue scale score were significantly improved in both groups. The range of motion (ROM) of stabilized segments in Dynesys group decreased from 7.1 ± 2.2° to 4.9 ± 2.2° (P < 0.05), while that of in PLIF group decreased from 7.3 ± 2.3° to 0° (P < 0.05). The ROM of the upper segments increased significantly in both groups at the final follow-up, the ROM was higher in the PLIF group. There were significantly more radiographic ASDs in the PLIF group than in the Dynesys group. The incidence of complications was comparable between groups. Conclusions Both Dynesys and PLIF can improve the clinical outcomes for lumbar degenerative disease. Compared to PLIF, Dynesys stabilization partially preserves the ROM of the stabilized segments, limits hypermobility in the upper adjacent segment, and may prevent the occurrence of ASD. PMID:26824851

  13. The Enceladus Ring

    NASA Technical Reports Server (NTRS)

    2006-01-01

    [figure removed for brevity, see original site] The Enceladus Ring (labeled)

    This excellent view of the faint E ring -- a ring feature now known to be created by Enceladus -- also shows two of Saturn's small moons that orbit within the ring, among a field of stars in the background.

    The E ring extends from three to eight Saturn radii -- about 180,000 kilometers (118,000 miles) to 482,000 kilometers (300,000 miles). Its full extent is not visible in this view.

    Calypso (22 kilometers, or 14 miles across) and Helene (32 kilometers, or 20 miles across) orbit within the E ring's expanse. Helene skirts the outer parts of the E ring, but here it is projected in front of a region deeper within the ring.

    Calypso and Helene are trojan satellites, or moons that orbit 60 degrees in front or behind a larger moon. Calypso is a Tethys trojan and Helene is a trojan of Dione.

    An interesting feature of note in this image is the double-banded appearance of the E-ring, which is created because the ring is somewhat fainter in the ringplane than it is 500-1,000 kilometers (300-600 miles) above and below the ringplane. This appearance implies that the particles in this part of the ring have nonzero inclinations (a similar affect is seen in Jupiter's gossamer ring). An object with a nonzero inclination does not orbit exactly at Saturn's ringplane. Instead, its orbit takes it above and below the ringplane. Scientists are not entirely sure why the particles should have such inclinations, but they are fairly certain that the reason involves Enceladus.

    One possible explanation is that all the E ring particles come from the plume of icy material that is shooting due south out of the moon's pole. This means all of the particles are created with a certain velocity out of the ringplane, and then they orbit above and below that plane.

    Another possible explanation is that Enceladus produces particles with a range of speeds, but the moon gravitationally

  14. Randomized clinical trial comparing lumbar percutaneous hydrodiscectomy with lumbar open microdiscectomy for the treatment of lumbar disc protrusions and herniations

    PubMed Central

    Cristante, Alexandre Fogaça; Rocha, Ivan Diasda; Marcon, Raphael Martus; de Barros Filho, Tarcísio Eloy Pessoa

    2016-01-01

    OBJECTIVES: Hydrodiscectomy is a new technique used for percutaneous spinal discectomy that employs a high-intensity stream of water for herniated disc ablation and tissue aspiration. No previous clinical study has examined the effects of percutaneous hydrodiscectomy. The aim of this study is to evaluate the outcomes of hydrodiscectomy compared to open microdiscectomy regarding pain, function, satisfaction, complications and recurrence rates. METHODS: In this randomized clinical trial, patients referred to our tertiary hospital for lumbar back pain were recruited and included in the study if they had disc protrusion or small herniation in only one level, without neurological deficits and with no resolution after six weeks of conservative treatment. One group underwent open microdiscectomy, and the other group underwent percutaneous microdiscectomy via hydrosurgery. Function was evaluated using the Oswestry Disability Index and pain was assessed using a visual analog scale. Evaluations were performed preoperatively, and then during the first week and at one, three, six and twelve months postoperatively. Personal satisfaction was verified. Clinicaltrials.gov: NCT01367860. RESULTS: During the study period, 20 patients were included in each arm and 39 completed one-year of follow-up (one patient died of unrelated causes). Both groups exhibited equal improvement on the visual analog scale and Oswestry evaluations after treatment, without any significant differences. The improvement in the lumbar visual analog scale score was not significant in the hydrodiscectomy group (p=0.138). The rates of infection, pain, recurrence and satisfaction were similar between the two groups. CONCLUSION: Percutaneous hydrodiscectomy was demonstrated to be as effective as open microdiscectomy for reducing pain. The rates of complications and recurrence of herniation were similar between groups. Patient satisfaction with the treatment was also similar between groups. PMID:27276397

  15. Lumbar extension exercises in conjunction with mechanical traction for the management of a patient with a lumbar herniated disc.

    PubMed

    Gagne, Allison R; Hasson, Scott M

    2010-05-01

    Low back pain resulting from lumbar disc herniation is a common reason for referral for physical therapy. There is no evidence to support the management of lumbar disc herniation and derangement using mechanical traction combined with lumbar extension exercises. Therefore, the purpose of this case report was to describe and discuss the use of mechanical traction in conjunction with lumbar extension exercises for a patient with a lumbar herniated disc. The patient was a 49-year-old male referred to physical therapy with a medical diagnosis of a lumbar herniated disc at L5-S1 with compression of the L5 nerve root confirmed by MRI. The patient's chief complaint was pain over the left lumbosacral and central lumbar region with radiating pain into the left buttock accompanied by numbness and tingling in the left lower leg and foot. The patient was seen for a total of 14 visits. The first 5 days (2 weeks) of therapy consisted of lumbar extension exercises. For the following nine visits (over a 3-week period), mechanical traction was added as an adjunct to the extension exercises. Outcome measures included the Oswestry Disability Questionnaire, Back Pain Function Scale (BPFS), and the Numeric Pain Rating Scale (NPRS). Results from initial evaluation to discharge (Oswestry: 36% to 0%; BPFS: 33/60 to 57/60; NPRS: 7/10 to 0/10) demonstrated that the patient no longer experienced low back pain and improved in terms of functional status and pain-related disability. The patient no longer complained of numbness and tingling in the left lower extremity and the goals for the patient had been attained. The data from this case report suggests lumbar extension exercises in conjunction with mechanical traction facilitated the patient's improvement in pain and return to prior level of function. PMID:20397860

  16. Intradural lumbar disc herniation after percutaneous endoscopic lumbar discectomy: case report.

    PubMed

    Tamaki, Yasuaki; Sakai, Toshinori; Miyagi, Ryo; Nakagawa, Takefumi; Shimakawa, Tateaki; Sairyo, Koichi; Chikawa, Takashi

    2015-09-01

    A 64-year-old man was referred to the authors with low-back pain (LBP) and right leg pain with a history of previously diagnosed lumbar disc herniation (LDH) at L4-5. He had undergone 2 percutaneous endoscopic lumbar discectomies (PELDs) for the herniation at another institution, and according to the surgical record of the second surgery, a dural tear occurred intraoperatively but was not repaired. Postoperative conservative treatments such as an epidural block and blood patch had not relieved his persistent LBP or right leg pain. Upon referral to the authors, MRI and myelography revealed an intradural LDH. The herniated mass was removed by durotomy, and posterior lumbar interbody fusion was performed. His symptoms were partially improved after surgery. Primary suture is technically difficult when a dural tear occurs during PELD. Therefore, close attention should be paid to avoiding such tears, and surgeons should increase their awareness of intradural LDH as a possible postoperative complication of PELD. PMID:26068274

  17. Transforaminal Lumbar Interbody Fusion for Lumbar Degenerative Disorders: Mini-open TLIF and Corrective TLIF

    PubMed Central

    HARA, Masahito; NISHIMURA, Yusuke; NAKAJIMA, Yasuhiro; UMEBAYASHI, Daisuke; TAKEMOTO, Masaya; YAMAMOTO, Yuu; HAIMOTO, Shoichi

    Minimally invasive transforaminal lumbar interbody fusion (TLIF) as a short fusion is widely accepted among the spine surgeons. However in the long fusion for degenerative kyphoscoliosis, corrective spinal fixation by an open method is thought to be frequently selected. Our objective is to study whether the mini-open TLIF and corrective TLIF contribute to the improvement of the spinal segmental and global alignment. We divided the patients who performed lumbar fixation surgery into three groups. Group 1 (G1) consisted of mini-open TLIF procedures without complication. Group 2 (G2) consisted of corrective TLIF without complication. Group 3 (G3) consisted of corrective TLIF with instrumentation-related complication postoperatively. In all groups, the lumbar lordosis (LL) highly correlated with developing surgical complications. LL significantly changed postoperatively in all groups, but was not corrected in the normal range in G3. There were statistically significant differences in preoperative and postoperative LL and mean difference between the pelvic incidence (PI) and LL between G3 and other groups. The most important thing not to cause the instrumentation-related failure is proper correction of the sagittal balance. In the cases with minimal sagittal imbalance with or without coronal imbalance, short fusion by mini-open TLIF or long fusion by corrective TLIF contributes to good clinical results if the lesion is short or easily correctable. However, if the patients have apparent sagittal imbalance with or without coronal imbalance, we should perform proper correction of the sagittal spinal alignment introducing various technologies. PMID:26119895

  18. Earth: A Ringed Planet?

    NASA Astrophysics Data System (ADS)

    Hancock, L. O.; Povenmire, H.

    2010-12-01

    Among the most beautiful findings of the Space Age have been the discoveries of planetary rings. Not only Saturn but also Jupiter, Uranus and Neptune have rings; Saturn’s ring system has structures newly discovered; even Saturn's moon Rhea itself has a ring. All these are apparently supplied by material from the planetary moons (Rhea's ring by Rhea itself). The question naturally arises, why should the Earth not have a ring, and on the other hand, if it does, why has it not been observed? No rings have yet been observed in the inner solar system, but after all, rings in the inner solar system might simply tend to be fainter and more transient than those of the outer solar system: the inner solar system is more affected by the solar wind, and the Sun’s perturbing gravitational influence is greater. J.A. O’Keefe first suggested (1980) that Earth might have a ring system of its own. An Earth ring could account for some climate events. O’Keefe remarked that formation or thickening of a ring system in Earth’s equatorial plane could drive glaciation by deepening the chill of the winter hemisphere. (It is very well established that volcanic dust is an effective agent for the extinction of sunlight; this factor can be overwhelmingly apparent in eclipse observations.) O’Keefe died in 2000 and the speculation was not pursued, but the idea of an Earth ring has a prima facie reasonableness that calls for its renewed consideration. The program of this note is to hypothesize that, as O’Keefe proposed: (a) an Earth ring system exists; (b) it affects Earth's weather and climate; (c) the tektite strewn fields comprise filaments of the ring fallen to Earth's surface on various occasions of disturbance by comets or asteroids. On this basis, and drawing on the world's weather records, together with the Twentieth Century Reanalysis by NCEP/CIRES covering the period 1870-2010 and the geology of the tektite strewn fields, we herein propose the hypothesized Earth ring

  19. Seal ring installation tool

    NASA Technical Reports Server (NTRS)

    Haselmaier, L. Haynes (Inventor)

    2004-01-01

    A seal ring tool that allows an installer to position a primary seal ring between hub ends of pipe flanges that are being assembled together. The tool includes a pivoting handle member and extension arms attached to the pivoting handle member. The ends of the arms have side indentation type longitudinal grooves angled toward one another for holding the primary seal ring in place between the hubs of respective pipes that are to be attached together. The arms of the tool can also have flat sides that can be used to abut against an optional second larger seal that is supported within a groove in one of the hub ends so that the second hub end can then be moved against the other side of the primary seal ring. Once the seal ring is positioned between the pipe hubs, the pipe hubs can be moved about the seal ring due to the flat sides of the arms of the tool. The tool eliminates the chances of damaging and contaminating seal rings being installed within pipe hubs that are being attached to one another.

  20. Hot piston ring tests

    NASA Technical Reports Server (NTRS)

    Allen, David J.; Tomazic, William A.

    1987-01-01

    As part of the DOE/NASA Automotive Stirling Engine Project, tests were made at NASA Lewis Research Center to determine whether appendix gap losses could be reduced and Stirling engine performance increased by installing an additional piston ring near the top of each piston dome. An MTI-designed upgraded Mod I Automotive Stirling Engine was used. Unlike the conventional rings at the bottom of the piston, these hot rings operated in a high temperature environment (700 C). They were made of a high temperature alloy (Stellite 6B) and a high temperature solid lubricant coating (NASA Lewis-developed PS-200) was applied to the cylinder walls. Engine tests were run at 5, 10, and 15 MPa operating pressure over a range of operating speeds. Tests were run both with hot rings and without to provide a baseline for comparison. Minimum data to assess the potential of both the hot rings and high temperature low friction coating was obtained. Results indicated a slight increase in power and efficiency, an increase over and above the friction loss introduced by the hot rings. Seal leakage measurements showed a significant reduction. Wear on both rings and coating was low.

  1. Dynamics of the Uranian Rings

    NASA Technical Reports Server (NTRS)

    Dermott, S. F.

    1984-01-01

    Some of the problems of the shepherding satellite model of Goldreich ant tremaine are discussed. The following topics are studied: (1) optical depths of the all the observed narrow rings; (2) satellite and ring separation timescales; (3) ring edge sharpness; (4) shock formation in narrow rings; (5) the existence of small satellites near the Uranian rings; and (6) the apse and node alignments of the eccentric and inclined rings.

  2. Dynamics of planetary rings

    NASA Astrophysics Data System (ADS)

    Araki, S.

    1991-02-01

    The modeling of the dynamics of particle collisions within planetary rings is discussed. Particles in the rings collide with one another because they have small random motions in addition to their orbital velocity. The orbital speed is roughly 10 km/s, while the random motions have an average speed of about a tenth of a millimeter per second. As a result, the particle collisions are very gentle. Numerical analysis and simulation of the ring dynamics, performed with the aid of a supercomputer, is outlined.

  3. Alternative parallel ring protocols

    NASA Technical Reports Server (NTRS)

    Mukkamala, R.; Foudriat, E. C.; Maly, Kurt J.; Kale, V.

    1990-01-01

    Communication protocols are know to influence the utilization and performance of communication network. The effect of two token ring protocols on a gigabit network with multiple ring structure is investigated. In the first protocol, a mode sends at most one message on receiving a token. In the second protocol, a mode sends all the waiting messages when a token is received. The behavior of these protocols is shown to be highly dependent on the number of rings as well as the load in the network.

  4. Theodolite Ring Lights

    NASA Technical Reports Server (NTRS)

    Clark, David

    2006-01-01

    Theodolite ring lights have been invented to ease a difficulty encountered in the well-established optical-metrology practice of using highly reflective spherical tooling balls as position references. A theodolite ring light produces a more easily visible reflection and eliminates the need for an autocollimating device. A theodolite ring light is a very bright light source that is well centered on the optical axis of the instrument. It can be fabricated, easily and inexpensively, for use on a theodolite or telescope of any diameter.

  5. [Lumbar disc herniation--diagnosis and treatment].

    PubMed

    Corniola, M-V; Tessitore, E; Schaller, K; Gautschi, O P

    2014-12-10

    A lumbar disc herniation (LDH) is a condition frequently encountered in primary care medicine. It may give rise to a compression of one or more nerve roots, which can lead to a nerve root irritation, a so-called radiculopathy, with or without a sensorimotor deficit. The majority of LDHs can be supported by means of a conservative treatment consisting of physical therapy, ergotherapy, analgetics, anti-inflammatory therapy or corticosteroids, which may be eventually administered by infiltrations. If a clinico-radiological correlation is present and moderate neurological deficit appears suddenly, if it is progressive under conservative treatment or if pain is poorly controlled by well-conducted conservative treatment performed during four to six months, surgery is then recommended. PMID:25632633

  6. Adjacent Segment Pathology after Lumbar Spinal Fusion.

    PubMed

    Lee, Jae Chul; Choi, Sung-Woo

    2015-10-01

    One of the major clinical issues encountered after lumbar spinal fusion is the development of adjacent segment pathology (ASP) caused by increased mechanical stress at adjacent segments, and resulting in various radiographic changes and clinical symptoms. This condition may require surgical intervention. The incidence of ASP varies with both the definition and methodology adopted in individual studies; various risk factors for this condition have been identified, although a significant controversy still exists regarding their significance. Motion-preserving devices have been developed, and some studies have shown their efficacy of preventing ASP. Surgeons should be aware of the risk factors of ASP when planning a surgery, and accordingly counsel their patients preoperatively. PMID:26435804

  7. An unexpectedly progressed lumbar herniated disk.

    PubMed

    Lipton, James A; McLeod, Geoffrey A

    2013-12-01

    The authors describe a case of a 26-year-old female military veteran who presented with low back pain that she attributed to a recent foot injury. The patient reported a history of lumbar pain while in the military that had been treated successfully with high-velocity, low-amplitude osteopathic manipulative treatment. The patient's current pain was improved with osteopathic manipulative treatment and gait correction. Several weeks after her initial presentation, the patient reported that she had had a herniated disk diagnosed 2 years earlier by means of magnetic resonance imaging. Updated magnetic resonance imaging was performed, the results of which revealed a large herniated disk that had caused severe stenosis. The patient was immediately referred to a neurosurgeon for consultation and subsequently underwent surgical treatment. PMID:24285036

  8. Anterior Lumbar Interbody Fusion as a Salvage Technique for Pseudarthrosis following Posterior Lumbar Fusion Surgery

    PubMed Central

    Mobbs, Ralph J.; Phan, Kevin; Thayaparan, Ganesha K.; Rao, Prashanth J.

    2015-01-01

    Study Design Retrospective analysis of prospectively collected observational data. Objective To assess the safety and efficacy of anterior lumbar interbody fusion (ALIF) as a salvage option for lumbar pseudarthrosis following failed posterior lumbar fusion surgery. Methods From 2009 to 2013, patient outcome data was collected prospectively over 5 years from 327 patients undergoing ALIF performed by a single surgeon (R.J.M.) with 478 levels performed. Among these, there were 20 cases of failed prior posterior fusion that subsequently underwent ALIF. Visual analog score (VAS), Oswestry Disability Index (ODI), and Short Form 12-item health survey (SF-12) were measured pre- and postoperatively. The verification of fusion was determined by utilizing a fine-cut computed tomography scan at 12-month follow-up. Results There was a significant difference between the preoperative (7.25 ± 0.8) and postoperative (3.1 ± 2.1) VAS scores (p < 0.0001). The ODI scale also demonstrated a statistically significant reduction from preoperative (56.3 ± 16.5) and postoperative (30.4 ± 19.3) scores (p < 0.0001). The SF-12 scores were significantly improved after ALIF salvage surgery: Physical Health Composite Score (32.18 ± 5.5 versus 41.07 ± 9.67, p = 0.0003) and Mental Health Composite Score (36.62 ± 12.25 versus 50.89 ± 10.86, p = 0.0001). Overall, 19 patients (95%) achieved successful fusion. Conclusions Overall, our results suggest that the ALIF procedure results not only in radiographic improvements in bony fusion but in significant improvements in the patient's physical and mental experience of pain secondary to lumbar pseudarthrosis. Future multicenter registry studies and randomized controlled trials should be conducted to confirm the long-term benefit of ALIF as a salvage option for failed posterior lumbar fusion. PMID:26835197

  9. Anterior Lumbar Interbody Fusion as a Salvage Technique for Pseudarthrosis following Posterior Lumbar Fusion Surgery.

    PubMed

    Mobbs, Ralph J; Phan, Kevin; Thayaparan, Ganesha K; Rao, Prashanth J

    2016-02-01

    Study Design Retrospective analysis of prospectively collected observational data. Objective To assess the safety and efficacy of anterior lumbar interbody fusion (ALIF) as a salvage option for lumbar pseudarthrosis following failed posterior lumbar fusion surgery. Methods From 2009 to 2013, patient outcome data was collected prospectively over 5 years from 327 patients undergoing ALIF performed by a single surgeon (R.J.M.) with 478 levels performed. Among these, there were 20 cases of failed prior posterior fusion that subsequently underwent ALIF. Visual analog score (VAS), Oswestry Disability Index (ODI), and Short Form 12-item health survey (SF-12) were measured pre- and postoperatively. The verification of fusion was determined by utilizing a fine-cut computed tomography scan at 12-month follow-up. Results There was a significant difference between the preoperative (7.25 ± 0.8) and postoperative (3.1 ± 2.1) VAS scores (p < 0.0001). The ODI scale also demonstrated a statistically significant reduction from preoperative (56.3 ± 16.5) and postoperative (30.4 ± 19.3) scores (p < 0.0001). The SF-12 scores were significantly improved after ALIF salvage surgery: Physical Health Composite Score (32.18 ± 5.5 versus 41.07 ± 9.67, p = 0.0003) and Mental Health Composite Score (36.62 ± 12.25 versus 50.89 ± 10.86, p = 0.0001). Overall, 19 patients (95%) achieved successful fusion. Conclusions Overall, our results suggest that the ALIF procedure results not only in radiographic improvements in bony fusion but in significant improvements in the patient's physical and mental experience of pain secondary to lumbar pseudarthrosis. Future multicenter registry studies and randomized controlled trials should be conducted to confirm the long-term benefit of ALIF as a salvage option for failed posterior lumbar fusion. PMID:26835197

  10. Minimally invasive lumbar decompression-the surgical learning curve.

    PubMed

    Kim, Choll W

    2016-08-01

    Commentary On: Ahn J, Iqbal A, Manning BT, Leblang S, Bohl DD, Mayo BC, et al. Minimally invasive lumbar decompression-the surgical learning curve. Spine J 2016:16:909-16. (in this issue). PMID:27545398

  11. Spinous Process Osteochondroma as a Rare Cause of Lumbar Pain.

    PubMed

    Rosa, Bárbara; Campos, Pedro; Barros, André; Karmali, Samir; Ussene, Esperança; Durão, Carlos; Alves da Silva, João; Coutinho, Nuno

    2016-01-01

    We present a case of a 5th Lumbar Vertebra (L5) spinous process osteochondroma as a rare cause of lumbar pain in an old patient. A 70-year-old male presented with progressive and disabling lower lumbar pain. Tenderness over the central and left paraspinal area of the lower lumbar region and a palpable mass were evident. CT scan showed a mass arising from the spinous process of L5. Marginal resection of the tumor was performed through a posterior approach. The histological study revealed an osteochondroma. After surgery, pain was completely relieved. After one year there was no evidence of local recurrence or symptoms. Osteochondromas rarely involve the spine, but when they do symptoms like pain, radiculopathy/myelopathy, or cosmetic deformity may occur. The imagiologic exam of election for diagnosis is CT scan. When symptomatic the treatment of choice is surgical resection. The most concerning complication of osteochondromas is malignant transformation, a rare event. PMID:27579204

  12. Spinous Process Osteochondroma as a Rare Cause of Lumbar Pain

    PubMed Central

    Rosa, Bárbara; Campos, Pedro; Barros, André; Karmali, Samir; Ussene, Esperança; Alves da Silva, João; Coutinho, Nuno

    2016-01-01

    We present a case of a 5th Lumbar Vertebra (L5) spinous process osteochondroma as a rare cause of lumbar pain in an old patient. A 70-year-old male presented with progressive and disabling lower lumbar pain. Tenderness over the central and left paraspinal area of the lower lumbar region and a palpable mass were evident. CT scan showed a mass arising from the spinous process of L5. Marginal resection of the tumor was performed through a posterior approach. The histological study revealed an osteochondroma. After surgery, pain was completely relieved. After one year there was no evidence of local recurrence or symptoms. Osteochondromas rarely involve the spine, but when they do symptoms like pain, radiculopathy/myelopathy, or cosmetic deformity may occur. The imagiologic exam of election for diagnosis is CT scan. When symptomatic the treatment of choice is surgical resection. The most concerning complication of osteochondromas is malignant transformation, a rare event.

  13. Safety of CT-Guided Lumbar Nerve Root Infiltrations

    PubMed Central

    Gossner, Johannes

    2014-01-01

    Summary Selective nerve root infiltrations are frequently performed in patients with lumbar radiculopathy. Computed tomography (CT) is now commonly used for image guidance. Despite the widespread use of CT-guided lumbar nerve root infiltrations few studies have systematically examined the safety of this approach. In a two-year period, 231 lumbar nerve root infiltrations were performed on in-patients and were retrospectively reviewed. No major complications like inflammation (especially spondylodiscitis), large haematomas requiring surgery, severe allergic reactions or spinal ischaemia occurred. In accordance with other published studies, CT-guided lumbar nerve root infiltrations seem to be safe. To minimize the risk of catastrophic neurological complications due to spinal ischaemia, careful needle placement dorsal to the nerve root and the use of a non-particulate corticosteroid, like dexamethasone, are advocated. PMID:25363255

  14. Lumbar puncture in patients using anticoagulants and antiplatelet agents.

    PubMed

    Domingues, Renan; Bruniera, Gustavo; Brunale, Fernando; Mangueira, Cristóvão; Senne, Carlos

    2016-08-01

    The use of anticoagulants and antiplatelet agents has largely increased. Diagnostic lumbar puncture in patients taking these drugs represents a challenge considering the opposing risks of bleeding and thrombotic complications. To date there are no controlled trials, specific guidelines, nor clear recommendations in this area. In the present review we make some recommendations about lumbar puncture in patients using these drugs. Our recommendations take into consideration the pharmacology of these drugs, the thrombotic risk according to the underlying disease, and the urgency in cerebrospinal fluid analysis. Evaluating such information and a rigorous monitoring of neurological symptoms after lumbar puncture are crucial to minimize the risk of hemorrhage associated neurological deficits. An individualized patient decision-making and an effective communication between the assistant physician and the responsible for conducting the lumbar puncture are essential to minimize potential risks. PMID:27556380

  15. Diagnosis of Lumbar Foraminal Stenosis using Diffusion Tensor Imaging

    PubMed Central

    Ohtori, Seiji; Suzuki, Munetaka; Oikawa, Yasuhiro; Yamanaka, Hajime; Tamai, Hiroshi; Kobayashi, Tatsuya; Orita, Sumihisa; Yamauchi, Kazuyo; Suzuki, Miyako; Aoki, Yasuchika; Watanabe, Atsuya; Kanamoto, Hirohito; Takahashi, Kazuhisa

    2016-01-01

    Diagnosis of lumbar foraminal stenosis remains difficult. Here, we report on a case in which bilateral lumbar foraminal stenosis was difficult to diagnose, and in which diffusion tensor imaging (DTI) was useful. The patient was a 52-year-old woman with low back pain and pain in both legs that was dominant on the right. Right lumbosacral nerve compression due to a massive uterine myoma was apparent, but the leg pain continued after a myomectomy was performed. No abnormalities were observed during nerve conduction studies. Computed tomography and magnetic resonance imaging indicated bilateral L5 lumbar foraminal stenosis. DTI imaging was done. The extraforaminal values were decreased and tractography was interrupted in the foraminal region. Bilateral L5 vertebral foraminal stenosis was treated by transforaminal lumbar interbody fusion and the pain in both legs disappeared. The case indicates the value of DTI for diagnosing vertebral foraminal stenosis. PMID:26949473

  16. Lumbar stabilization: core concepts and current literature, Part 1.

    PubMed

    Barr, Karen P; Griggs, Miriam; Cadby, Todd

    2005-06-01

    The factors that affect lumbar stability have been an area of extensive research. The clinical application of this research in the form of lumbar stabilization exercise programs has become a common treatment of low back pain and is also increasingly used by athletes to improve performance and by the general public for health and the prevention of injury. This article includes a review of the key concepts behind lumbar stabilization. The literature regarding how those with low back pain differ in their ability to stabilize the spine from those without low back pain is discussed, and an overview of current research that assesses the benefits of a lumbar stabilization program to treat low back pain is provided. PMID:15905663

  17. Intradural lumbar disc herniations: report of three cases.

    PubMed

    Prestar, F J; Schattke, H H

    1995-09-01

    Intradural lumbar disc herniation is a rare pathological entity. Three new cases among a series of 5000 lumbar spine operations are added to the about 60 previous case reports in the literature. None of our patients had undergone lumbar spine surgery before. In one patient the location of the free disc fragment was medial within the dural sac; in two patients the free disc fragment had penetrated the dural sac from the axilla of the nerve root. Pathogenesis is discussed (congenital adhesions of the dura mater to the posterior longitudinal ligament at the lower lumbar spine; weakness of the dura mater ventrally and at the axilla of the nerve root). By multiplanar MRI, the free disc hernia within the dural sac may be shown preoperatively. PMID:8542333

  18. Degenerative lumbar spinal stenosis and its imposters: three case studies

    PubMed Central

    Ammendolia, Carlo

    2014-01-01

    Degenerative lumbar spinal stenosis causing neurogenic claudicaton is a common condition impacting walking ability in older adults. There are other highly prevalent conditions in this patient population that have similar signs and symptoms and cause limited walking ability. The purpose of this study is to highlight the diagnostic challenges using three case studies of older adults who present with limited walking ability who have imaging evidence of degenerative lumbar spinal stenosis. PMID:25202160

  19. Laparoscopic Repair of Left Lumbar Hernia After Laparoscopic Left Nephrectomy

    PubMed Central

    Milone, Luca; Gumbs, Andrew; Turner, Patricia

    2010-01-01

    Lumbar hernias, rarely seen in clinical practice, can be acquired after open or laparoscopic flank surgery. We describe a successful laparoscopic preperitoneal mesh repair of multiple trocar-site hernias after extraperitoneal nephrectomy. All the key steps including creating a peritoneal flap, reducing the hernia contents, and fixation of the mesh are described. A review of the literature on this infrequent operation is presented. Laparoscopic repair of lumbar hernias has all the advantages of laparoscopic ventral hernia repair. PMID:21333197

  20. Hemorrhage from lumbar artery following percutaneous renal biopsy

    PubMed Central

    Devi, B. Vijayalakshmi; Lakshmi, B. Sangeetha; Supraja, C.; Vanajakshmma, V.; Ram, R.; Rajasekhar, D.; Lakshmi, A. Y.; Sivakumar, V.

    2015-01-01

    We present a 58-year-old lady who underwent ultrasound-guided renal biopsy for suspected acute glomerulonephritis. Within minutes, the radiologist noticed an echogenic band around left kidney and in the muscular planes. Computerized tomography revealed focal active contrast extravasation from arcuate or interlobular artery in lower pole of left kidney and lumbar artery at third lumbar vertebra. The bleeding vessel was occluded with gelfoam. PMID:26199475

  1. Lumbar intervertebral disc degeneration and related factors in Korean firefighters

    PubMed Central

    Jang, Tae-Won; Ahn, Yeon-Soon; Byun, Junsu; Lee, Jong-In; Kim, Kun-Hyung; Kim, Youngki; Song, Han-Soo; Lee, Chul-Gab; Kwon, Young-Jun; Yoon, Jin-Ha; Jeong, Kyoungsook

    2016-01-01

    Objectives The job of firefighting can cause lumbar burden and low back pain. This study aimed to identify the association between age and lumbar intervertebral disc degeneration and whether the association differs between field and administrative (non-field) firefighters. Methods Subjects were selected using a stratified random sampling method. Firefighters were stratified by geographic area, gender, age and type of job. First, 25 fire stations were randomly sampled considering regional distribution. Then firefighters were stratified by gender, age and their job and randomly selected among the strata. A questionnaire survey and MRI scans were performed, and then four radiologists used Pfirrmann classification methods to determine the grade of lumbar intervertebral disc degeneration. Results Pfirrmann grade increased with lumbar intervertebral disc level. Analysis of covariance showed that age was significantly associated with lumbar intervertebral disc degeneration (p<0.05). The value of β (parameter estimate) was positive at all lumbar intervertebral disc levels and was higher in the field group than in the administrative group at each level. In logistic regression analysis, type of job was statistically significant only with regard to the L4–5 intervertebral disc (OR 3.498, 95% CI 1.241 to 9.860). Conclusions Lumbar intervertebral disc degeneration is associated with age, and field work such as firefighting, emergency and rescue may accelerate degeneration in the L4–5 intervertebral disc. The effects of field work on lumbar intervertebral disc degeneration were not clear in discs other than at the level L4–5. PMID:27354080

  2. Heating Saturn's Clumpy Rings

    NASA Astrophysics Data System (ADS)

    Turner, Neal J.; Morishima, Ryuji; Spilker, Linda J.

    2015-11-01

    We model Cassini CIRS data using a Monte Carlo radiative transfer -- thermal balance technique first developed for protostellar disks, with the goals of:1. Exploring whether the A- and B-ring temperatures' variation with viewing angle is consistent with the wake structures suggested by the observed azimuthal asymmetry in optical depth, by analytic arguments, and by numerical N-body modeling.2. Better constraining the shape, size, spacing and optical depths of substructure in the A-ring, using the unexpectedly high temperatures observed at equinox. If the wake features have high enough contrast, Saturn-shine may penetrate the gaps between the wakes and heat thering particles both top and bottom.3. Determining how much of the heating of the A- and B-rings' unlit sides is due to radiative transport and how much is due to particle motions, especially vertical motions. This will help in constraining the rings' surface densities and masses.

  3. Storage Ring EDM Experiments

    NASA Astrophysics Data System (ADS)

    Semertzidis, Yannis K.

    2016-04-01

    Dedicated storage ring electric dipole moment (EDM) methods show great promise advancing the sensitivity level by a couple orders of magnitude over currently planned hadronic EDM experiments. We describe the present status and recent updates of the field.

  4. Saturn's dynamic D ring

    USGS Publications Warehouse

    Hedman, M.M.; Burns, J.A.; Showalter, M.R.; Porco, C.C.; Nicholson, P.D.; Bosh, A.S.; Tiscareno, M.S.; Brown, R.H.; Buratti, B.J.; Baines, K.H.; Clark, R.

    2007-01-01

    The Cassini spacecraft has provided the first clear images of the D ring since the Voyager missions. These observations show that the structure of the D ring has undergone significant changes over the last 25 years. The brightest of the three ringlets seen in the Voyager images (named D72), has transformed from a narrow, <40-km wide ringlet to a much broader and more diffuse 250-km wide feature. In addition, its center of light has shifted inwards by over 200 km relative to other features in the D ring. Cassini also finds that the locations of other narrow features in the D ring and the structure of the diffuse material in the D ring differ from those measured by Voyager. Furthermore, Cassini has detected additional ringlets and structures in the D ring that were not observed by Voyager. These include a sheet of material just interior to the inner edge of the C ring that is only observable at phase angles below about 60??. New photometric and spectroscopic data from the ISS (Imaging Science Subsystem) and VIMS (Visual and Infrared Mapping Spectrometer) instruments onboard Cassini show the D ring contains a variety of different particle populations with typical particle sizes ranging from 1 to 100 microns. High-resolution images reveal fine-scale structures in the D ring that appear to be variable in time and/or longitude. Particularly interesting is a remarkably regular, periodic structure with a wavelength of ??? 30 ?? km extending between orbital radii of 73,200 and 74,000 km. A similar structure was previously observed in 1995 during the occultation of the star GSC5249-01240, at which time it had a wavelength of ??? 60 ?? km. We interpret this structure as a periodic vertical corrugation in the D ring produced by differential nodal regression of an initially inclined ring. We speculate that this structure may have formed in response to an impact with a comet or meteoroid in early 1984. ?? 2006 Elsevier Inc. All rights reserved.

  5. Sensitivity of lumbar spine loading to anatomical parameters.

    PubMed

    Putzer, Michael; Ehrlich, Ingo; Rasmussen, John; Gebbeken, Norbert; Dendorfer, Sebastian

    2016-04-11

    Musculoskeletal simulations of lumbar spine loading rely on a geometrical representation of the anatomy. However, this data has an inherent inaccuracy. This study evaluates the influence of defined geometrical parameters on lumbar spine loading utilising five parametrised musculoskeletal lumbar spine models for four different postures. The influence of the dimensions of vertebral body, disc, posterior parts of the vertebrae as well as the curvature of the lumbar spine was studied. Additionally, simulations with combinations of selected parameters were conducted. Changes in L4/L5 resultant joint force were used as outcome variable. Variations of the vertebral body height, disc height, transverse process width and the curvature of the lumbar spine were the most influential. These parameters can be easily acquired from X-rays and should be used to morph a musculoskeletal lumbar spine model for subject-specific approaches with respect to bone geometry. Furthermore, the model was very sensitive to uncommon configurations and therefore, it is advised that stiffness properties of discs and ligaments should be individualised. PMID:26680014

  6. The cortical and cerebellar representation of the lumbar spine.

    PubMed

    Boendermaker, Bart; Meier, Michael L; Luechinger, Roger; Humphreys, B Kim; Hotz-Boendermaker, Sabina

    2014-08-01

    Eight decades after Penfield's discovery of the homunculus only sparse evidence exists on the cortical representation of the lumbar spine. The aim of our investigation was the description of the lumbar spine's cortical representation in healthy subjects during the application of measured manual pressure. Twenty participants in the prone position were investigated during functional magnetic resonance imaging (fMRI). An experienced manual therapist applied non-painful, posterior-to-anterior (PA) pressure on three lumbar spinous processes (L1, L3, and L5). The pressure (30 N) was monitored and controlled by sensors. The randomized stimulation protocol consisted of 68 pressure stimuli of 5 s duration. Blood oxygenation level dependent (BOLD) responses were analyzed in relation to the lumbar stimulations. The results demonstrate that controlled PA pressure on the lumbar spine induced significant activation patterns. The major new finding was a strong and consistent activation bilaterally in the somatosensory cortices (S1 and S2). In addition, bilateral activation was located medially in the anterior cerebellum. The activation pattern also included other cortical areas probably related to anticipatory postural adjustments. These revealed stable somatosensory maps of the lumbar spine in healthy subjects can subsequently be used as a baseline to investigate cortical and subcortical reorganization in low back pain patients. PMID:24464423

  7. Mosaic of Saturn's rings

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This detailed mosaic of the underside of the Cassini Division was obtained by Voyager 1 with a resolution of about 10 kilometers. The classical Cassini Division appears here to the right of center as five bright rings with substantial blacks gap on either side. The inner edge of the A Ring, to the left of center, is the brightest part of this image. The fine-scale wave structure in this region has been interpreted as being the result of gravitational density waves.

  8. Saturn's B rings

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This narrow-angle camera image of Saturn's B Ring and Cassini Division was taken through the Clear filter from a distance of 12.6 million km on 3 November 1980. The Cassini Division separating the A and B Rings is clearly not an empty region. The Division shows several substantial well-defined ringlets. JPL managed the Voyager Project for NASA's Office of Space Science.

  9. Saturn's E ring

    NASA Technical Reports Server (NTRS)

    Baum, W. A.; Kreidl, T.; Westphal, J. A.; Danielson, G. E.; Seidelmann, P. K.; Pascu, D.; Currie, D. G.

    1981-01-01

    Observations of the tenuous E ring of Saturn made by an earth-based CCD system at the time of the ring-plane crossing of March 1980 are presented. The observations were made with the CCD system attached to the 1.8-m Perkins reflector at Lowell Observatory using a pupil mask behind a focal plane mask to suppress telescopic diffraction. Photometric analysis of the CCD images reveal the edge-on brightness profile of the ring, beginning at a distance of 3 Saturn radii, to peak sharply in the vicinity of the orbit of Enceladus at about 4 Saturn radii, then decrease to a distance of over 8 Saturn radii. In addition, beyond Enceladus, the edge-on width of the ring is observed to increase with radial distance, reaching nearly 5 arcsec at 7 Saturn radii. Observations suggest, on the one hand, that the E ring is associated with Enceladus and possibly represents material ejected from the satellite, and on the other, that the ring is at an early stage in its evolution.

  10. The effect of lumbar total disc replacement on the spinopelvic alignment and range of motion of the lumbar spine.

    PubMed

    Chung, Sung Soo; Lee, Chong Suh; Kang, Chang Seok; Kim, Sang Hyun

    2006-07-01

    A lumbar total disc replacement (TDR) is a type of motion-preserving surgery, which aims to restore and maintain the normal range of motion (ROM) and the sagittal balance of the spine. However, little is known regarding how the spinopelvic alignment and ROM of the lumbar spine are influenced by the lumbar TDR with ProDisc. This study retrospectively analyzed the sagittal alignment and ROM of the lumbar spine in 26 consecutive patients who had undergone the TDR with ProDisc with a minimum follow-up of 24 months. A standing lateral radiograph, which included the femoral heads and dynamic flexion-extension lateral radiographs of the spine were taken before surgery and at the follow-up visit. The radiological parameters included the sacral tilt, the pelvic tilt, and the lumbar lordosis. The segmental lordosis and ROM were also measured at each operative level. Nineteen patients underwent a single-level TDR and 7 patients underwent a double-level TDR. The mean lumbar lordosis increased significantly from 30.5 degrees to 40.8 degrees in all patients who underwent TDR without any significant changes in the sacral tilt and pelvic tilt at the latest follow-up (P<0.05). In the patients who underwent single-level TDR, the mean segmental lordosis at the L5-S1 and L4-5 operative levels increased significantly from 15.8 degrees to 23.2 degrees and from 14.1 degrees to 24.9 degrees, respectively. The mean ROM at L5-S1 and L4-5 increased significantly from 7.1 degrees to 11.2 degrees and from 11.4 degrees to 14.6 degrees, respectively. The sagittal balance and ROM of the lumbar spine improved significantly after the lumbar TDR. PMID:16825999

  11. Postural Cueing to Increase Lumbar Lordosis Increases Lumbar Multifidus Activation During Trunk Stabilization Exercises: Electromyographic Assessment Using Intramuscular Electrodes.

    PubMed

    Beneck, George J; Story, John W; Donald, Shelby

    2016-04-01

    Study Design Controlled laboratory study, repeated-measures design. Background Diminished multifidus activation and cross-sectional area are frequent findings in persons with low back pain. Increasing lumbar lordosis has been shown to increase activation of the multifidus with a minimal increase in activation of the long global extensors during unsupported sitting. Objectives To examine the influence of postural cueing to increase lumbar lordosis on lumbar extensor activation during trunk stabilization exercises. Methods Thirteen asymptomatic participants (9 male, 4 female) were instructed to perform 6 trunk stabilization exercises using a neutral position and increasing lumbar lordosis. Electrical activity of the deep multifidus and longissimus thoracis was recorded using fine-wire intramuscular electrodes. The mean root-mean-square of the electromyography (EMG) signal obtained during each exercise was normalized to a maximum voluntary isometric contraction (MVIC). A 2-way, repeated-measures analysis of variance (posture by exercise) was performed for each muscle. Results When averaged across the 6 exercises, postural cueing to increase lumbar lordosis resulted in greater multifidus EMG activity compared to performing the exercises in a neutral posture (35.3% ± 15.1% versus 29.5% ± 11.2% MVIC). No significant increase in longissimus thoracis EMG activity was observed when exercising with cueing to increase lumbar lordosis. Conclusion This study suggests that postural cueing to increase lumbar lordosis during trunk stabilization exercises may better promote multifidus activation than traditional stabilization exercises alone. Future studies are needed to determine whether increasing lumbar lordosis improves multifidus activation in persons with low back pain. J Orthop Sports Phys Ther 2016;46(4):293-299. Epub 8 Mar 2016. doi:10.2519/jospt.2016.6174. PMID:26954268

  12. Propellers in Saturn's rings

    NASA Astrophysics Data System (ADS)

    Sremcevic, M.; Stewart, G. R.; Albers, N.; Esposito, L. W.

    2014-04-01

    Theoretical studies and simulations have demonstrated the effects caused by objects embedded in planetary rings [5, 8]. Even if the objects are too small to be directly observed, each creates a much larger gravitational imprint on the surrounding ring material. These strongly depend on the mass of the object and range from "S" like propeller-shaped structures for about 100m-sized icy bodies to the opening of circumferential gaps as in the case of the embedded moons Pan and Daphnis and their corresponding Encke and Keeler Gaps. Since the beginning of the Cassini mission many of these smaller objects (~ 100m in size) have been identified in Saturn's A ring through their propeller signature in the images [10, 7, 9, 11]. Furthermore, recent Cassini observations indicate the possible existence of objects embedded even in Saturn's B and C ring [6, 2]. In this paper we present our new results about by now classical A ring propellers and more enigmatic B ring population. Due to the presence of self-gravity wakes the analysis of propeller brightness in ISS images always bears some ambiguity [7, 9] and consequently the exact morphology of propellers is not a settled issue. In 2008 we obtained a fortunate Cassini Ultraviolet Imaging Spectrograph (UVIS) occultation of the largest A ring propeller Bleriot. Utilizing Cassini ISS images we obtain Bleriot orbit and demonstrate that UVIS Persei Rev42 occultation did cut across Bleriot about 100km downstream from the center. The occultation itself shows a prominent partial gap and higher density outer flanking wakes, while their orientation is consistent with a downstream cut. While in the UVIS occultation the partial gap is more prominent than the flanking wakes, the features mostly seen in Bleriot images are actually flanking wakes. One of the most interesting aspects of the A ring propellers are their wanderings, or longitudinal deviations from a pure circular orbit [11]. We numerically investigated the possibility of simple moon

  13. Biomechanical effect of altered lumbar lordosis on intervertebral lumbar joints during the golf swing: a simulation study.

    PubMed

    Bae, Tae Soo; Cho, Woong; Kim, Kwon Hee; Chae, Soo Won

    2014-11-01

    Although the lumbar spine region is the most common site of injury in golfers, little research has been done on intervertebral loads in relation to the anatomical-morphological differences in the region. This study aimed to examine the biomechanical effects of anatomical-morphological differences in the lumbar lordosis on the lumbar spinal joints during a golf swing. The golf swing motions of ten professional golfers were analyzed. Using a subject-specific 3D musculoskeletal system model, inverse dynamic analyses were performed to compare the intervertebral load, the load on the lumbar spine, and the load in each swing phase. In the intervertebral load, the value was the highest at the L5-S1 and gradually decreased toward the T12. In each lumbar spine model, the load value was the greatest on the kypholordosis (KPL) followed by normal lordosis (NRL), hypolordosis (HPL), and excessive lordosis (EXL) before the impact phase. However, results after the follow-through (FT) phase were shown in reverse order. Finally, the load in each swing phase was greatest during the FT phase in all the lumbar spine models. The findings can be utilized in the training and rehabilitation of golfers to help reduce the risk of injury by considering individual anatomical-morphological characteristics. PMID:25162173

  14. What's up with witch rings?

    PubMed

    Heard, Priscilla; Phillips, David

    2015-01-01

    'Witch rings' are well-known novelty rings that show a size-change illusion when rotated. We have replicated the illusion of expansion of the reflections in the rings in a variety of contexts with animations, though not as yet so successfully imitated the sense that the whole ring expands and contracts. PMID:26489222

  15. [Degenerative disorders of the lumbar spine Total disc replacement as an alternative to lumbar fusion?].

    PubMed

    Mayer, H M

    2005-10-01

    Spinal fusion is accepted worldwide as a therapeutic option for the treatment of degenerative disorders of the lumbar spine. Because there are only few evidence-based data available supporting the usefulness of lumbar spinal fusion, its questionable benefit as well as the potential for complications are the reasons for an ongoing discussion. In recent years, total disc replacement with implants has emerged as an alternative treatment. Although early results are promising, there is still a lack of evidence-based data as well as of long-term results for this technology. This article gives a critical update on the implant systems currently in use (SB Charité, Prodisc II L, Maverick, Flexicore, Mobidisc), which all have to be considered as "first-generation" implants. Morphological and clinical sequelae of the different biomechanical properties, designs, and materials have not yet been sufficiently investigated. There is no international consensus on the indication spectrum and on the preoperative diagnosis of discogenic low back pain. The same is true for the (minimally invasive) surgical access strategies. Complication rates seem to be somewhat lower compared to spinal fusion techniques. There are no standardized revision concepts in cases of implant failure. Lumbar disc replacement has opened a new era in spinal surgery with a still unproven benefit for the patient. It is strongly recommended that these techniques should only be applied by experienced and well-trained spine surgeons. Until evidence-based data are available, all patients should be treated under scientific study conditions with close postoperative follow-up. PMID:16034627

  16. Management of lumbar zygapophysial (facet) joint pain

    PubMed Central

    Manchikanti, Laxmaiah; Hirsch, Joshua A; Falco, Frank JE; Boswell, Mark V

    2016-01-01

    AIM: To investigate the diagnostic validity and therapeutic value of lumbar facet joint interventions in managing chronic low back pain. METHODS: The review process applied systematic evidence-based assessment methodology of controlled trials of diagnostic validity and randomized controlled trials of therapeutic efficacy. Inclusion criteria encompassed all facet joint interventions performed in a controlled fashion. The pain relief of greater than 50% was the outcome measure for diagnostic accuracy assessment of the controlled studies with ability to perform previously painful movements, whereas, for randomized controlled therapeutic efficacy studies, the primary outcome was significant pain relief and the secondary outcome was a positive change in functional status. For the inclusion of the diagnostic controlled studies, all studies must have utilized either placebo controlled facet joint blocks or comparative local anesthetic blocks. In assessing therapeutic interventions, short-term and long-term reliefs were defined as either up to 6 mo or greater than 6 mo of relief. The literature search was extensive utilizing various types of electronic search media including PubMed from 1966 onwards, Cochrane library, National Guideline Clearinghouse, clinicaltrials.gov, along with other sources including previous systematic reviews, non-indexed journals, and abstracts until March 2015. Each manuscript included in the assessment was assessed for methodologic quality or risk of bias assessment utilizing the Quality Appraisal of Reliability Studies checklist for diagnostic interventions, and Cochrane review criteria and the Interventional Pain Management Techniques - Quality Appraisal of Reliability and Risk of Bias Assessment tool for therapeutic interventions. Evidence based on the review of the systematic assessment of controlled studies was graded utilizing a modified schema of qualitative evidence with best evidence synthesis, variable from level I to level V

  17. DC-Powered Jumping Ring

    NASA Astrophysics Data System (ADS)

    Jeffery, Rondo N.; Amiri, Farhang

    2016-02-01

    The classroom jumping ring demonstration is nearly always performed using alternating current (AC), in which the ring jumps or flies off the extended iron core when the switch is closed. The ring jumps higher when cooled with liquid nitrogen (LN2). We have performed experiments using DC to power the solenoid and find similarities and significant differences from the AC case. In particular, the ring does not fly off the core but rises a short distance and then falls back. If the ring jumps high enough, the rising and the falling motion of the ring does not follow simple vertical motion of a projectile. This indicates that there are additional forces on the ring in each part of its motion. Four possible stages of the motion of the ring with DC are identified, which result from the ring current changing directions during the jump in response to a changing magnetic flux through the moving ring.

  18. Mapping Ring Particle Cooling across Saturn's Rings with Cassini CIRS

    NASA Astrophysics Data System (ADS)

    Brooks, Shawn M.; Spilker, L. J.; Edgington, S. G.; Pilorz, S. H.; Deau, E.

    2010-10-01

    Previous studies have shown that the rings' thermal inertia, a measure of their response to changes in the thermal environment, varies from ring to ring. Thermal inertia can provide insight into the physical structure of Saturn's ring particles and their regoliths. Low thermal inertia and quick temperature responses are suggestive of ring particles that have more porous or fluffy regoliths or that are riddled with cracks. Solid, coherent particles can be expected to have higher thermal inertias (Ferrari et al. 2005). Cassini's Composite Infrared Spectrometer has recorded millions of spectra of Saturn's rings since its arrival at Saturn in 2004 (personal communication, M. Segura). CIRS records far infrared radiation between 10 and 600 cm-1 (16.7 and 1000 µm) at focal plane 1 (FP1), which has a field of view of 3.9 mrad. Thermal emission from Saturn's rings peaks in this wavelength range. FP1 spectra can be used to infer ring temperatures. By tracking how ring temperatures vary, we can determine the thermal inertia of the rings. In this work we focus on CIRS observations of the shadowed portion of Saturn's rings. The thermal budget of the rings is dominated by the solar radiation absorbed by its constituent particles. When ring particles enter Saturn's shadow this source of energy is abruptly cut off. As a result, ring particles cool as they traverse Saturn's shadow. From these shadow observations we can create cooling curves at specific locations across the rings. We will show that the rings' cooling curves and thus their thermal inertia vary not only from ring to ring, but by location within the individual rings. This research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA. Copyright 2010 California Institute of Technology. Government sponsorship acknowledged.

  19. Saturn's Other Ring Current

    NASA Astrophysics Data System (ADS)

    Crary, F. J.

    2014-04-01

    Saturn's main rings orbit the planet within an atmosphere and ionosphere of water, oxygen and hydrogen, produced by meteoritic impacts on and ultraviolet photodesorbtion of the ring particles [Johnson et al., 2006; Luhmann et al., 2006; Tseng et al., 2010]. The neutral atmosphere itself has only been tentatively detected through ultraviolet fluorescents of OH [Hall et al., 1996] while the ionosphere was observed in situ by the Cassini spacecraft shortly after orbital insertion [Coates et al.,2005; Tokar et al. 2005, Waite et al. 2005]. Although the plasma flow velocity of this ionosphere is not well-constrained, but the close association with the rings suggests that its speed would be couppled to the keplarian velocity of the rings themselves. As a result, the motion of the plasma through Saturn's magnetic field would produce an induced voltage, oriented away from the planet outside synchronous orbit and towards the planet inside synchronous orbit. Such a potential could result in currents flowing across the ring plane and closeing along magnetic field lines and through Saturn's ionosphere at latitudes between 36o and 48o. Cassini observations of whistler-mode plasma wave emissions [Xin et al.,2006] centered on synchronous orbit (1.76 Rs, mapping to 41o latitude) have been interpreted as a product of field-aligned electron beams associated with such a current. This presentation will investigate the magnitude of these currents and the resulting Joule heating of the ionosphere. An important constraint is that no auroral ultraviolet emissions have been observed at the relevant latitudes. In contrast, Joule heating could affect infrared emissions from H3+. Variations in H3+ emission associated with Saturn's rings have been reported by O'Donoghue et al., 2013, and interpreted as a result of ring "rain", i.e. precipitating water group species from the rings which alter ionosphereic chemistry and H3+ densities. As noted by O'Donoghue et al., this interpretation may be

  20. Stacked Corrugated Horn Rings

    NASA Technical Reports Server (NTRS)

    Sosnowski, John B.

    2010-01-01

    This Brief describes a method of machining and assembly when the depth of corrugations far exceeds the width and conventional machining is not practical. The horn is divided into easily machined, individual rings with shoulders to control the depth. In this specific instance, each of the corrugations is identical in profile, and only differs in diameter and outer profile. The horn is segmented into rings that are cut with an interference fit (zero clearance with all machining errors biased toward contact). The interference faces can be cut with a reverse taper to increase the holding strength of the joint. The taper is a compromise between the interference fit and the clearance of the two faces during assembly. Each internal ring is dipped in liquid nitrogen, then nested in the previous, larger ring. The ring is rotated in the nest until the temperature of the two parts equalizes and the pieces lock together. The resulting assay is stable, strong, and has an internal finish that cannot be achieved through other methods.

  1. Piston Ring Pressure Distribution

    NASA Technical Reports Server (NTRS)

    Kuhn, M.

    1943-01-01

    The discovery and introduction of the internal combustion engine has resulted in a very rapid development in machines utilizing the action of a piston. Design has been limited by the internal components of the engine, which has been subjected to ever increasing thermal and mechanical stresses, Of these internal engine components, the piston and piston rings are of particular importance and the momentary position of engine development is not seldom dependent upon the development of both of the components, The piston ring is a well-known component and has been used in its present shape in the steam engine of the last century, Corresponding to its importance, the piston ring has been a rich field for creative activity and it is noteworthy that in spite of this the ring has maintained its shape through the many years. From the many and complicated designs which have been suggested as a packing between piston and cylinder wall hardly one suggestion has remained which does not resemble the original design of cast iron rectangular ring.

  2. Lumbar pseudarthrosis: a review of current diagnosis and treatment.

    PubMed

    Chun, Danielle S; Baker, Kevin C; Hsu, Wellington K

    2015-10-01

    OBJECT Failed solid bony fusion, or pseudarthrosis, is a well-known complication of lumbar arthrodesis. Recent advances in radiographic technology, biologics, instrumentation, surgical technique, and understanding of the local biology have all aided in the prevention and treatment of pseudarthrosis. Here, the current literature on the diagnosis and management of lumbar pseudarthroses is reviewed. METHODS A systematic literature review was conducted using the MEDLINE and Embase databases in order to search for the current radiographie diagnosis and surgical treatment methods published in the literature (1985 to present). Inclusion criteria included: 1) published in English; 2) level of evidence I-III; 3) diagnosis of degenerative lumbar spine conditions and/or history of lumbar spine fusion surgery; and 4) comparative studies of 2 different surgical techniques or comparative studies of imaging modality versus surgical exploration. RESULTS Seven studies met the inclusion criteria for current radiographie imaging used to diagnose lumbar pseudarthrosis. Plain radiographs and thin-cut CT scans were the most common method for radiographie diagnosis. PET has been shown to be a valid imaging modality for monitoring in vivo active bone formation. Eight studies compared the surgical techniques for managing and preventing failed lumbar fusion. The success rates for the treatment of pseudarthrosis are enhanced with the use of rigid instrumentation. CONCLUSIONS Spinal fusion rates have improved secondary to advances in biologies, instrumentation, surgical techniques, and understanding of local biology. Treatment of lumbar pseudarthrosis includes a variety of surgical options such as replacing loose instrumentation, use of more potent biologies, and interbody fusion techniques. Prevention and recognition are important tenets in the algorithm for the management of spinal pseudarthrosis. PMID:26424334

  3. Hepatocellular Carcinoma Supplied by the Right Lumbar Artery

    SciTech Connect

    Miyayama, Shiro Yamashiro, Masashi; Okuda, Miho; Yoshie, Yuichi; Sugimori, Natsuki; Igarashi, Saya; Nakashima, Yoshiko; Matsui, Osamu

    2010-02-15

    This study evaluated the clinical features of hepatocellular carcinoma (HCC) supplied by the right lumbar artery. Eleven patients with HCC supplied by the right lumbar artery were treated with chemoembolization. The patients' medical records were retrospectively analyzed. All patients underwent 6.7 {+-} 3.7 (mean {+-} SD) chemoembolization sessions, and the hepatic arterial branches were noted as being attenuated. The right inferior phrenic artery (IPA) was also embolized in 10 patients. The interval between initial chemoembolization and chemoembolization of the lumbar artery supply was 53.2 {+-} 26.9 months. Mean tumor diameter was 3.1 {+-} 2.4 cm and was located at the surface of S7 and S6. The feeding-branch arose proximal to the bifurcation of the dorsal ramus and muscular branches (n = 8) or from the muscular branches (n = 3) of the right first (n = 10) or second lumbar artery (n = 1). The anterior spinal artery originated from the tumor-feeding lumbar artery in one patient. All feeders were selected, and embolization was performed after injection of iodized oil and anticancer drugs (n = 10) or gelatin sponge alone in a patient with anterior spinal artery branching (n = 1). Eight patients died from tumor progression 10.1 {+-} 4.6 months later, and two patients survived 2 and 26 months, respectively. The remaining patient died of bone metastases after 32 months despite liver transplantation 10 months after chemoembolization. The right lumbar artery supplies HCC located in the bare area of the liver, especially in patients who undergo repeated chemoembolization, including chemoembolization by way of the right IPA. Chemoembolization by way of the right lumbar artery may be safe when the feeder is well selected.

  4. Rings in the solar system

    SciTech Connect

    Pollack, J.B.; Cuzzi, J.N.

    1981-11-01

    Saturn, Jupiter, and Uranus have rings with different structure and composition. The rings consist of tiny masses in independent orbits. Photographs and data obtained by the Voyager project have aided in the understanding of Saturn's rings. Spokes have been found in B ring and boards, knots, and twist in F ring. Particles on the order of a micrometer in size are believed to occur in F, B, and A rings. The dominant component is water ice. The rings of Uranus are narrow and separated by broad empty regions. The technique used to study them has been stellar occulation. Nothing is known of particle size. The dominant component is believed to be silicates rich in compounds that absorb sunlight. Jupiter's rings consist of 3 main parts: a bright ring, a diffuse disk, and a halo. Use of Pioneer 10 data and other techniques have indicated particle sizes on the order of several micrometers and some at least a centimeter in diameter. The architecture of the ring system results from the interplay of a number of forces. These include gravitational forces due to moons outside the rings and moonlets embedded in them, electromagnetic forces due to the planet's rotating magnetic field, and even the gentle forces exerted by the dilute gaseous medium in which the rings rotate. Each of these forces is discussed. Several alternative explanations of how the rings arose are considered. The primary difference in these hypotheses is the account of the relationship between the ring particles of today and the primordial ring material. (SC)

  5. Physics of planetary rings

    NASA Astrophysics Data System (ADS)

    Gorkavyi, N.

    2007-08-01

    It is difficult to enumerate all the surprises presented by the planetary rings. The Saturnian rings are stratified into thousands of ringlets and the Uranian rings are compressed into narrow streams, which for some reason or other differ from circular orbits like the wheel of an old bicycle. The edge of the rings is jagged and the rings themselves are pegged down under the gravitational pressure of the satellites, bending like a ship's wake. There are spiral waves, elliptical rings, strange interlacing of narrow ringlets, and to cap it all one has observed in the Neptunian ring system three dense, bright arcs - like bunches of sausages on a transparent string. For celestial mechanics this is a spectacle as unnatural as a bear's tooth in the necklace of the English queen. In the dynamics of planetary rings the physics of collective interaction was supplemented by taking collisions between particles into account. One was led to study a kinetic equation with a rather complex collision integral - because the collisions are inelastic - which later on made it possible, both by using the Chapman-Enskog method and by using the solution of the kinetic equation for a plasma in a magnetic field, to reduce it to a closed set of (hydrodynamical) moment equations [1]. The hydrodynamical instabilities lead to the growth of short-wavelength waves and large-scale structures of the Saturnian rings [1]. We have shown that the formation of the existing dense Uranian rings is connected with the capture of positively drifting ring particles in inner Lindblad resonances which arrest this drift [1]. After the formation of dense rings at the positions of satellite resonances the collective interaction between resonant particles is amplified and the rings can leave the resonance and drift away from the planet and the parent resonance. We can expect in the C ring an appreciable positive ballistic particle drift caused by the erosion of the B ring by micrometeorites. It is therefore natural

  6. Performing lumbar punctures for suspected CNS infections: experience and practice of trainee doctors.

    PubMed

    Defres, Sylviane; Mayer, Josephine; Backman, Ruth; Kneen, Rachel

    2015-11-01

    Lumbar punctures are essential in the management of suspected CNS infections. However, despite clear guidelines their use can be haphazard. This survey investigated the training, knowledge and experience of UK doctors in training in relation to lumbar punctures. PMID:26551497

  7. Rings dominate western Gulf

    NASA Astrophysics Data System (ADS)

    Vidal L., Francisco V.; Vidal L., Victor M. V.; Molero, José María Pérez

    Surface and deep circulation of the central and western Gulf of Mexico is controlled by interactions of rings of water pinched from the gulf's Loop Current. The discovery was made by Mexican oceanographers who are preparing a full-color, 8-volume oceanographic atlas of the gulf.Anticyclonic warm-core rings pinch off the Loop Current at a rate of about one to two per year, the scientists of the Grupo de Estudios Oceanográficos of the Instituto de Investigaciones Eléctricas (GEO-IIE) found. The rings migrate west until they collide with the continental shelf break of the western gulf, almost always between 22° and 23°N latitude. On their westward travel they transfer angular momentum and vorticity to the surrounding water, generating cyclonic circulations and vortex pairs that completely dominate the entire surface and deep circulation of the central and western gulf.

  8. Deployable Fresnel Rings

    NASA Technical Reports Server (NTRS)

    Kennedy, Timothy F.; Fink, Patrick W.; Chu, Andrew W.; Lin, Gregory Y.

    2014-01-01

    Deployable Fresnel rings (DFRs) significantly enhance the realizable gain of an antenna. This innovation is intended to be used in combination with another antenna element, as the DFR itself acts as a focusing or microwave lens element for a primary antenna. This method is completely passive, and is also completely wireless in that it requires neither a cable, nor a connector from the antenna port of the primary antenna to the DFR. The technology improves upon the previous NASA technology called a Tri-Sector Deployable Array Antenna in at least three critical aspects. In contrast to the previous technology, this innovation requires no connector, cable, or other physical interface to the primary communication radio or sensor device. The achievable improvement in terms of antenna gain is significantly higher than has been achieved with the previous technology. Also, where previous embodiments of the Tri-Sector antenna have been constructed with combinations of conventional (e.g., printed circuit board) and conductive fabric materials, this innovation is realized using only conductive and non-conductive fabric (i.e., "e-textile") materials, with the possible exception of a spring-like deployment ring. Conceptually, a DFR operates by canceling the out-of-phase radiation at a plane by insertion of a conducting ring or rings of a specific size and distance from the source antenna, defined by Fresnel zones. Design of DFRs follow similar procedures to those outlined for conventional Fresnel zone rings. Gain enhancement using a single ring is verified experimentally and through computational simulation. The experimental test setup involves a microstrip patch antenna that is directly behind a single-ring DFR and is radiating towards a second microstrip patch antenna. The first patch antenna and DFR are shown. At 2.42 GHz, the DFR improves the transmit antenna gain by 8.6 dB, as shown in Figure 2, relative to the wireless link without the DFR. A figure illustrates the

  9. Sliding-Ring Catenanes.

    PubMed

    Fernando, Isurika R; Frasconi, Marco; Wu, Yilei; Liu, Wei-Guang; Wasielewski, Michael R; Goddard, William A; Stoddart, J Fraser

    2016-08-17

    Template-directed protocols provide a routine approach to the synthesis of mechanically interlocked molecules (MIMs), in which the mechanical bonds are stabilized by a wide variety of weak interactions. In this Article, we describe a strategy for the preparation of neutral [2]catenanes with sliding interlocked electron-rich rings, starting from two degenerate donor-acceptor [2]catenanes, consisting of a tetracationic cyclobis(paraquat-p-phenylene) cyclophane (CBPQT(4+)) and crown ethers containing either (i) hydroquinone (HQ) or (ii) 1,5-dioxynaphthalene (DNP) recognition units and carrying out four-electron reductions of the cyclophane components to their neutral forms. The donor-acceptor interactions between the CBPQT(4+) ring and both HQ and DNP units present in the crown ethers that stabilize the [2]catenanes are weakened upon reduction of the cyclophane components to their radical cationic states and are all but absent in their fully reduced states. Characterization in solution performed by UV-vis, EPR, and NMR spectroscopic probes reveals that changes in the redox properties of the [2]catenanes result in a substantial decrease of the energy barriers for the circumrotation and pirouetting motions of the interlocked rings, which glide freely through one another in the neutral states. The solid-state structures of the fully reduced catenanes reveal profound changes in the relative dispositions of the interlocked rings, with the glycol chains of the crown ethers residing in the cavities of the neutral CBPQT(0) rings. Quantum mechanical investigations of the energy levels associated with the four different oxidation states of the catenanes support this interpretation. Catenanes and rotaxanes with sliding rings are expected to display unique properties. PMID:27398609

  10. Lumbar puncture refusal in febrile convulsion.

    PubMed

    Ling, S G; Boey, C C

    2000-10-01

    A descriptive study was carried out on patients admitted for febrile convulsion over a two-year period to determine rate of lumbar puncture (LP) refusal, factors associated with LP refusal and outcome of such patients. From 77 patients indicated and requested for LP, 19 (25%) patients refused the procedure. Refusal of LP was significantly more common among the Malay ethnic group (p = 0.01) but not significantly associated with age,gender or whether the patient was admitted for a first or recurrent febrile convulsion. Half of the patients who refused LP had to be started empirically on antibiotics for meningitis. Patients who refused LP were also 8.5 times more likely to discharge themselves "at own risk" (AOR), compared to other patients with febrile convulsion (p = 0.004). In conclusion, LP refusal is a common problem in the local setting and is a hindrance to the proper management of patients with fever and seizure. Appropriate measures must be carried out to educate the public, particularly those from the Malay ethnic group on the safety and usefulness of the procedure. Reasons for patients discharging AOR following LP refusal also need to be addressed and problems rectified. PMID:11281439