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Sample records for lumbar apophyseal ring

  1. Clinical and Radiologic Analysis of Posterior Apophyseal Ring Separation Associated with Lumbar Disc Herniation

    PubMed Central

    Bae, Jung-Sik; Rhee, Woo-Tack; Kim, Woo-Jae; Ha, Seong-Il; Lim, Jae-Hyeon

    2013-01-01

    Objective We analyzed the clinical and radiologic features of posterior apophyseal ring separation (PARS) with lumbar disc herniation and suggest the proper management options according to the PARS characteristics. Methods We reviewed case series of patients with PARS who underwent surgery of lumbar disc herniation. Preoperative symptoms, neurologic status, Body Mass Index, preoperative and postoperative Visual Analogue Scale (VAS) and Korean-Oswestry Disability Index (K-ODI) scores, operation types were obtained. PARS size, locations, the degree of resection were assessed. Results PARS was diagnosed in 109 (7.5%) patients among 1448 patients given surgical treatment for single level lumbar disc herniation. There were 55 (50.5%) small PARS and 54 (49.5%) large PARS. Among the large PARS group, 15 (27.8%) had lower endplate PARS of upper vertebra at the level of disc herniation. Thirty-nine (72.2%) were upper endplate PARS of lower vertebra. Among the group with upper endplate PARS of lower vertebra, unresected PARS was diagnosed in 12 (30.8%) cases and resected PARS was diagnosed in 27 (69.2%) cases. VAS and K-ODI scores changes were 3.6±2.9 and 5.4±6.4 in the unresected PARS group, 5.8±2.1 and 11.3±7.1 in the resected PARS group. The group with upper endplate PARS of lower vertebra showed significant difference of VAS (p=0.01) and K-ODI (p=0.013) score changes between unresected and resected PARS groups. Conclusion The large PARS of upper endplate in lower vertebra should be removed during the surgery of lumbar disc herniation. High level or bilateral side of PARS should be widely decompressed and arthrodesis procedures are necessary if there is a possibility of secondary instability. PMID:23634263

  2. V-rod technique for direct repair surgery of pediatric lumbar spondylolysis combined with posterior apophyseal ring fracture.

    PubMed

    Sumita, Takayuki; Sairyo, Koichi; Shibuya, Isao; Kitahama, Yoshihiro; Kanamori, Yasuo; Matsumoto, Hironori; Koga, Soichi; Kitagawa, Yasuhiro; Dezawa, Akira

    2013-06-01

    We report a pediatric baseball player having both a fracture of the posterior ring apophysis and spondylolysis. He was presented to a primary care physician complaining of back pain and leg pain. Despite conservative treatment for 3 months, the pain did not subside. He was referred to our clinic, and surgical intervention was carried out. First, a bony fragment of the caudal L5 apophyseal ring was removed following fenestration at the L5-S interlaminal space, bilaterally: and decompression of the bilateral S1 nerve roots was confirmed. Next, pseudoarthrosis of the L5 pars was refreshed and pedicle screws were inserted bilaterally. A v-shaped rod was inserted beneath the L5 spinous process, which stabilized the pars defects. After the surgery, back pain and leg pain completely disappeared. In conclusion, the v-rod technique is appropriate for the spondylolysis direct repair surgery, especially, in case the loose lamina would have a partial laminotomy.

  3. Apophyseal fracture of the lumbar spine in adolescence.

    PubMed

    Clark, J E

    1991-06-01

    A case of adolescent lumbar disc herniation with apophyseal fracture is reported. The patient, a 12-year-old boy, experienced sudden onset of pain during athletic activity. Examination revealed tenderness on palpation of the L-5 and S-1 spinous processes, straightening of the lumbar spine, and exquisite pain on 10 degrees of hyperextension. Straight leg raising, Lasègue's, and bowstring tests were all positive. Magnetic resonance imaging and computed tomography confirmed the diagnosis. Treatment included exercise, ibuprofen administration, and limitation of sports activity. At 23 months, the patient is symptom-free. A literature review of 20 cases with computed tomographic or myelographic diagnosis is presented, and conservative and surgical treatment programs are outlined.

  4. 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

  5. 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

  6. Apophysitis of the acromion.

    PubMed

    Morisawa, K; Umemura, A; Kitamura, T; Ide, J; Yamaga, M; Takagi, K

    1996-01-01

    We treated three patients with apophysitis of the acromion. These patients were two male athletes 12 and 14 years of age, respectively, and one female athlete 13 years of age. They reported pain at the top of the shoulder during and after shoulder movement while playing sports but had no rest pain or disturbance of daily activities. Physical examination demonstrated marked local tenderness at the acromion and slight warmth. X-ray films showed sclerosis and irregularity of the secondary ossification center of the acromion. Bone scintigraphy carried out on one patient demonstrated increased uptake in that region. Conservative treatment was used for these patients. Recovery was gradual but satisfactory.

  7. 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

  8. 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

  9. 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.

  10. Traction apophysitis of the medial malleolus.

    PubMed

    Ishii, T; Miyagawa, S; Hayashi, K

    1994-09-01

    We report the cases of three children with chronic injuries of the medial tibial malleolus caused by traction injuries during sport. All three had the triad of swelling of the medial malleolus, tenderness over its anterior part, and pain on forced valgus movement of the foot. Radiographs showed bilateral accessory ossification centres and MRI demonstrated partial avulsion or avulsion fracture of the apophyseal cartilage and fragmentation of the accessory centres. A review of 134 young basketball players showed that 25% had tenderness of the anterior medial malleolus. This high rate indicates that traction apophysitis of the medial malleolus is not uncommon in children as a sports-related disorder.

  11. 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

  12. 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

  13. 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

  14. 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

  15. [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.

  16. [Lumbar hernia].

    PubMed

    Bednarek, Marcin; Bolt, Leszek; Biesiada, Zbigniew; Zub-Pokrowiecka, Anna

    2012-01-01

    Lumbar region constitutes one of the least common localizations for hernia formation. There are only slightly more than 300 cases found in English literature till the end of the 20th century, while there are only 8 cases presented in Polish literature. Exceptionally rare incidence together with diagnostic dilemma related to it made us to present cases of 2 patients operated on in the 2nd Chair of Surgery of Jagiellonian University Medical College due to lumbar hernia.

  17. Lumbar lordosis.

    PubMed

    Been, Ella; Kalichman, Leonid

    2014-01-01

    Lumbar lordosis is a key postural component that has interested both clinicians and researchers for many years. Despite its wide use in assessing postural abnormalities, there remain many unanswered questions regarding lumbar lordosis measurements. Therefore, in this article we reviewed different factors associated with the lordosis angle based on existing literature and determined normal values of lordosis. We reviewed more than 120 articles that measure and describe the different factors associated with the lumbar lordosis angle. Because of a variety of factors influencing the evaluation of lumbar lordosis such as how to position the patient and the number of vertebrae included in the calculation, we recommend establishing a uniform method of evaluating the lordosis angle. Based on our review, it seems that the optimal position for radiologic measurement of lordosis is standing with arms supported while shoulders are flexed at a 30° angle. There is evidence that many factors, such as age, gender, body mass index, ethnicity, and sport, may affect the lordosis angle, making it difficult to determine uniform normal values. Normal lordosis should be determined based on the specific characteristics of each individual; we therefore presented normal lordosis values for different groups/populations. There is also evidence that the lumbar lordosis angle is positively and significantly associated with spondylolysis and isthmic spondylolisthesis. However, no association has been found with other spinal degenerative features. Inconclusive evidence exists for association between lordosis and low back pain. Additional studies are needed to evaluate these associations. The optimal lordotic range remains unknown and may be related to a variety of individual factors such as weight, activity, muscular strength, and flexibility of the spine and lower extremities. PMID:24095099

  18. Apophysitis of the ischial tuberosity mimicking a neoplasm on magnetic resonance imaging.

    PubMed

    Yamamoto, Tetsuji; Akisue, Toshihiro; Nakatani, Tetsuya; Kawamoto, Teruya; Hitora, Toshiaki; Marui, Takashi; Kurosaka, Masahiro

    2004-12-01

    We present multimodality imaging features of an ischial tuberosity apophysitis in a 13-year-old boy who was an active baseball pitcher. Roentgenography of the pelvis and computed tomography showed mild irregularity in the inferior margin of the left ischial tuberosity. T1-weighted MRI showed a wide area with low signal intensity in the left ischial body; T2-weighted fat-suppression images showed areas with markedly high signal intensity in the ischial apophysis and body and the surrounding periosteum; contrast-enhanced T1-weighted fat-suppression MRI showed that the ischial body, surrounding periosteum, and origin of the hamstring muscles strongly enhanced; technetium-99m scintigraphic scans showed increased isotope uptake in the entire ischial body. Histological specimens obtained from the bone showed increased osteoblastic activity, edema, and proliferation of benign spindle cells and small vessels in the bone marrow spaces. In the present case, because MR imaging demonstrated extensive signal abnormalities involving the apophysis, periosteum, and intramedullary portion of bone, a neoplasm could not be excluded, and a biopsy was undertaken.

  19. “Effectiveness of interventions in reducing pain and maintaining physical activity in children and adolescents with calcaneal apophysitis (Sever’s disease): a systematic review”

    PubMed Central

    2013-01-01

    Background Calcaneal apophysitis, also commonly known as sever’s disease, is a condition seen in children usually aged between 8–15 years. Conservative therapies, such as taping, heel lifts and orthotic intervention are accepted management practices for calcaneal apophysitis, though there is very little high quality research examining the efficacy of such treatment modalities. Previous narrative literature reviews and opinion pieces provide some evidence for the use of heel raises or orthoses. The aim of this manuscript was to complete a systemic review on the treatment options for calcaneal apophysitis as measured by pain reduction and maintenance of physical activity. Methods A search strategy completed by two reviewers examined nine databases from inception to May 2012. Search terms included heel pain, children, adolescent, calcaneal apophysitis, sever’s disease, treatment, and management (full text publications, human studies). Systematic reviews, randomised control trials, case series, and case studies were included. The reference lists of the selected articles were also examined. The methodology, quality and risk of bias was examined and assessed using the PEDro scale. Results Nine articles were retrieved including three clinical trials involving randomisation, two case series, two retrospective case reviews, and two case reports. Effect size calculations and a meta analysis were unable to be completed due to the limited data reported within the literature. Numerous treatment options were reported throughout the literature, though few were examined against a control or alternate treatment option in well-designed trials. The limited evidence indicated that orthoses provided greater short-term pain relief than heel raises. Health practitioners should view these results with caution, as there were apparent methodological problems with the employed study design and limited follow-up of participants. Conclusion There is limited evidence to support the use

  20. Laparoscopic lumbar hernia repair.

    PubMed

    Madan, Atul K; Ternovits, Craig A; Speck, Karen E; Pritchard, F Elizabeth; Tichansky, David S

    2006-04-01

    Lumbar hernias are rare clinical entities that often pose a challenge for repair. Because of the surrounding anatomy, adequate surgical herniorraphy is often difficult. Minimally invasive surgery has become an option for these hernias. Herein, we describe two patients with lumbar hernias (one with a recurrent traumatic hernia and one with an incisional hernia). Both of these hernias were successfully repaired laparoscopically.

  1. 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

  2. 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 ...

  3. 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 ...

  4. 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

  5. [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

  6. Incarcerated inferior lumbar (Petit's) hernia.

    PubMed

    Astarcioğlu, H; Sökmen, S; Atila, K; Karademir, S

    2003-09-01

    Petit's hernia is an uncommon abdominal wall defect in the inferior lumbar triangle. Colonic incarceration through the inferior lumbar triangle, which causes mechanical obstructive symptoms, necessitates particular diagnostic and management strategy. We present a rare case of inferior lumbar hernia, leading to mechanical bowel obstruction, successfully treated with prosthetic mesh reinforcement repair.

  7. Lumbar spinal epidural angiolipoma.

    PubMed

    Nanassis, Kimon; Tsitsopoulos, Parmenion; Marinopoulos, Dimitrios; Mintelis, Apostolos; Tsitsopoulos, Philippos

    2008-04-01

    Spinal angiolipomas are rare benign tumours most commonly found in the thoracic spine. A case of an extradural lumbar angiolipoma in a 47-year-old female is described. She had a recent history of lower back pain accompanied by sciatica. Lumbar MRI revealed a dorsal epidural mass at the L2-L3 level. The patient underwent a bilateral laminectomy, in which the tumour was totally excised. The pathological examination indicated haemangiolipoma. Post-operatively, the patient's neurological signs and symptoms improved remarkably quickly. MRI at 6 and 18 months after surgery revealed no evidence of tumour recurrence.

  8. Lumbar hernia: a diagnostic dilemma.

    PubMed

    Ahmed, Syed Tausif; Ranjan, Rajeeva; Saha, Subhendu Bikas; Singh, Balbodh

    2014-04-15

    Lumbar hernia is one of the rare cases that most surgeons are not exposed to. Hence the diagnosis can be easily missed. This leads to delay in the treatment causing increased morbidity. We report a case of lumbar hernia in a middle-aged woman. It was misdiagnosed as lipoma by another surgeon. It was a case of primary acquired lumbar hernia in the superior lumbar triangle. Clinical and MRI findings were correlated to reach the diagnosis. We also highlight the types, the process of diagnosis and the surgical repair of lumbar hernias. We wish to alert our fellow surgeons to keep the differential diagnosis of the lumbar hernia in mind before diagnosing any lumbar swelling as lipoma.

  9. 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

  10. 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

  11. 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.

  12. [The role of computed tomography and magnetic resonance in assessing degenerative arthropathy of the lumbar articular facets].

    PubMed

    Leone, A; Aulisa, L; Tamburrelli, F; Lupparelli, S; Tartaglione, T

    1994-11-01

    Degenerative arthropathy of the lumbar facet joints remains a debated issue relative to both its etiopathogenesis and its clinical significance. The authors studied 9 autoptic specimens by means of CT and MRI: the diagnostic value of the two methods was assessed taking the histopathologic findings of the relative specimens as the gold standard. The following signs of degenerative arthropathy were investigated in each specimen: cartilaginous wears, hypertrophy of the articular processes, osteophytosis, subchondral sclerosis and geodes and capsular and ligamentous calcifications. CT clearly demonstrated the characteristic signs of arthropathy, although failing to assess the cartilaginous wears in the early degeneration phases. Cartilaginous surface tears were directly depicted by MRI in the specimens showing medium and advanced degeneration. In our opinion, CT represents the examination of choice in the diagnosis of degenerative arthropathy of the lumbar apophyseal joints. Nevertheless, human trials are needed to assess MR capabilities in better detailing subchondral bone structure and in depicting the joint capsule and the synovial membrane and fluid as a major MR potential to diagnose back pain syndromes arising from the posterior arch.

  13. [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

  14. [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.

  15. Lumbar facet syndromes.

    PubMed

    Beresford, Zach M; Kendall, Richard W; Willick, Stuart E

    2010-01-01

    Low back pain is a common presenting complaint to sports medicine providers. The lumbar spine is a complex anatomic structure with multiple potential pain generators. Epidemiologic studies have shown that the intervertebral disc is the most common pain generator in all patients with low back pain. The facet joints may account for 15%-40% of low back pain. It can be challenging at times to establish a firm diagnosis of facet pain. Facet pain can have different presentations, and pain emanating from other lumbopelvic structures can present similarly as facet joint pain. This article reviews the anatomy and biomechanics of the lumbar facet joints, presenting symptoms and physical examination findings seen with facet pain. We also will discuss diagnostic and treatment paradigms that are helpful to the clinician treating low back pain in athletes.

  16. Iopamidol in lumbar myelography.

    PubMed

    Kleefield, J; Chirico-Post, J; Levine, H L; Srinivasan, M K; Harris, J M; Rommel, A J; Robbins, A H

    1983-08-01

    Iopamidol is a new, nonionic, water-soluble contrast material currently undergoing clinical trials for intravascular and intrathecal use in Europe and the United States. In this study, 12 patients underwent lumbar myelography with this agent. For each subject, up to 12 mL of iopamidol (at 200 mg I/mL) was employed. The myelograms obtained were highly satisfactory. No serious adverse reactions were observed. The most common side effect--headache--occurred in seven patients. However, six of the seven headaches were mild and transient, and did not require treatment. Nausea occurred in two patients, back pain in two patients, hypotension and hypertension each in one patient. All of these reactions were mild and self-limited. Iopamidol appears to be a safe and conveniently used agent for lumbar myelography.

  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. PMID:27186250

  19. Electrodiagnosis of lumbar radiculopathy.

    PubMed

    Barr, Karen

    2013-02-01

    The evaluation of patients with suspected lumbar radiculopathy is one of the most common reasons patients are referred for electrodiagnostic testing. The utility of this study depends on the expertise of the physician who plans, performs, and completes the study. This article reviews the strengths and weaknesses of electrodiagnosis to make this diagnosis, as well as the clinical reasoning of appropriate study planning. The current use of electrodiagnostic testing to determine prognosis and treatment outcomes is also discussed.

  20. 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

  1. Planetary rings

    NASA Technical Reports Server (NTRS)

    Cook, A. F.

    1980-01-01

    Observations of the Rings of Saturn from the Pioneer spacecraft, discovery of the Ring of Jupiter, ground based polarimetry of the Rings of Saturn and some theoretical studies may be combined to markedly advance our understanding of the Rings of Jupiter, Saturn and Uranus. In particular, narrow rings can be self-gravitatingly stable inside Roche's limit and outside another closer limit. They can be created from a satellite which evolves across its Roche limit either by inward tidal drift or by growth of the planet by accretion. These considerations suggest that Neptune may well be surrounded by one or more narrow rings like those of Uranus.

  2. Postlaminectomy Bilateral Lumbar Intraspinal Synovial Cysts

    PubMed Central

    Cho, Sung Ik; Lee, Jung Hwan

    2016-01-01

    Lumbar intraspinal synovial cysts are included in the difference diagnosis of lumbar radiculopathy. Developing imaging modalities has result in increased reporting about these lesions. However, the case of bilateral new lumbar intraspinal synovial cysts after laminectomy has been rarely reported. We report of a rare case with bilateral lumbar intraspinal synovial cysts after laminectomy, requiring surgical excision. PMID:27799997

  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. 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.

  5. 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

  6. 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.

  7. 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 ...

  8. 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

  9. Percutaneous endoscopic decompression for lumbar spinal stenosis.

    PubMed

    Ahn, Yong

    2014-11-01

    Percutaneous endoscopic lumbar discectomy has become a representative minimally invasive spine surgery for lumbar disc herniation. Due to the remarkable evolution in the techniques available, the paradigm of spinal endoscopy is shifting from treatments of soft disc herniation to those of lumbar spinal stenosis. Lumbar spinal stenosis can be classified into three categories according to pathological zone as follows: central stenosis, lateral recess stenosis and foraminal stenosis. Moreover, percutaneous endoscopic decompression (PED) techniques may vary according to the type of lumbar stenosis, including interlaminar PED, transforaminal PED and endoscopic lumbar foraminotomy. However, these techniques are continuously evolving. In the near future, PED for lumbar stenosis may be an efficient alternative to conventional open lumbar decompression surgery.

  10. [Lumbar stabilization exercises].

    PubMed

    Vásquez-Ríos, Jorge Rodrigo; Nava-Bringas, Tania Inés

    2014-01-01

    Antecedentes: el ejercicio es la intervención con mayor grado de evidencia de eficacia para el tratamiento del dolor crónico de la espalda baja, con beneficio superior en términos de dolor y funcionalidad, en comparación con cualquiera otra intervención. Existe una amplia variedad de ejercicios diseñados; sin embargo, actualmente los llamados ejercicios de estabilización lumbar adquiririeron una popularidad creciente entre los clínicos que están en contacto con enfermedades de la columna. Sin embargo, existe controversia en cuanto a la prescripción adecuada de los mismos y los múltiples protocolos publicados. Objetivo: analizar la bibliografía científica acerca del uso y prescripción de estos ejercicios para favorecer la mejor toma de decisiones enlos clínicos y diseñar, con base a la evidencia, el programa más adecuado para cada paciente. Conclusión: se encontró que este programa es una herramienta esencial en el tratamiento del dolor de espalda baja, en la etapa terapéutica y en la preventiva.

  11. [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

  12. [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.

  13. 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

  14. A lumbar disc surgery predictive score card.

    PubMed

    Finneson, B E

    1978-06-01

    A lumbar disc surgery predictive score card or questionnaire has been developed to assess potential candidates for excision of a herniated lumbar disc who have not previously undergone lumbar spine surgery. It is not designed to encompass patients who are being considered for other types of lumbar spine surgery, such as decompressive laminectomy or fusion. In an effort to make the "score card" usable by almost all physicians who are involved in lumbar disc surgery, only studies which have broad acceptance and are generally employed are included. Studies which have less widespread use such as electromyogram, discogram, venogram, special psychologic studies (MMPI, pain drawings) have been purposely excluded.

  15. Jupiter's ring

    NASA Technical Reports Server (NTRS)

    1979-01-01

    First evidence of a ring around the planet Jupiter is seen in this photograph taken by Voyager 1 on March 4, 1979. The multiple exposure of the extremely thin faint ring appears as a broad light band crossing the center of the picture. The edge of the ring is 1,212,000 km from the spacecraft and 57,000 km from the visible cloud deck of Jupiter. The background stars look like broken hair pins because of spacecraft motion during the 11 minute 12 second exposure. The wavy motion of the star trails is due to the ultra-slow natural oscillation of the spacecraft (with a period of 78 seconds). The black dots are geometric calibration points in the camera. The ring thickness is estimated to be 30 km or less. The photograph was part of a sequence planned to search for such rings in Jupiter's equatorial plane. The ring has been invisible from Earth because of its thinness and its transparency when viewed at any angle except straight on. JPL manages and controls the Voyager Project for NASA's Office of Space Science.

  16. 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

  17. Chondroblastoma of the lumbar vertebra.

    PubMed

    Leung, L Y; Shu, S J; Chan, M K; Chan, C H

    2001-12-01

    Chondroblastoma of the vertebra is a very rare condition. To our knowledge fewer than 20 cases have been reported in the world literature. We report a 54-year-old man with chondroblastoma of the fifth lumbar vertebra. The clinical and radiological aspects of the tumor are discussed, emphasizing the presence of an extraosseous mass suggestive of locally aggressive behavior. PMID:11810169

  18. 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

  19. Endoscopic lumbar foraminotomy.

    PubMed

    Evins, Alexander I; Banu, Matei A; Njoku, Innocent; Elowitz, Eric H; Härtl, Roger; Bernado, Antonio; Hofstetter, Christoph P

    2015-04-01

    Foraminal stenosis frequently causes radiculopathy in lumbar degenerative spondylosis. Endoscopic transforaminal techniques allow for foraminal access with minimal tissue disruption. However, the effectiveness of foraminal decompression by endoscopic techniques has yet to be studied. We evaluate radiographic outcome of endoscopic transforaminal foraminotomies performed at L3-L4, L4-L5, and L5-S1 on cadaveric specimens. Before and after the procedures, three dimensional CT scans were obtained to measure foraminal height and area. Following the foraminotomies, complete laminectomies and facetectomies were performed to assess for dural tears or nerve root damage. L3-L4 preoperative foraminal height increased by 8.9%, from 2.12±0.13cm to 2.27±0.14cm (p<0.01), and foraminal area increased by 24.8% from 2.21±0.18cm(2) to 2.72±0.19cm(2) (p<0.01). At L4-L5, preoperative foraminal height was 1.87±0.17cm and area was 1.78±0.18cm(2). Endoscopic foraminotomies resulted in a 15.3% increase of foraminal height (2.11±0.15cm, p<0.05) and 44.8% increase in area of (2.51±0.21cm(2), p<0.01). At L5-S1, spondylitic changes caused diminished foraminal height (1.26±0.14cm) and foraminal area (1.17±0.18cm(2)). Postoperatively, foraminal height increased by 41.6% (1.74±0.09cm, p<0.05) and area increased by 98.7% (2.08±0.17cm(2), p<0.01). Subsequent inspection via a standard midline approach revealed one dural tear of an S1 nerve root. Endoscopic foraminotomies allow for effective foraminal decompression, though clinical studies are necessary to further evaluate complications and efficacy.

  20. 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

  1. Ghostly Ring

    NASA Technical Reports Server (NTRS)

    2008-01-01

    [figure removed for brevity, see original site] Click on image for poster version

    This image shows a ghostly ring extending seven light-years across around the corpse of a massive star. The collapsed star, called a magnetar, is located at the exact center of this image. NASA's Spitzer Space Telescope imaged the mysterious ring around magnetar SGR 1900+14 in infrared light. The magnetar itself is not visible in this image, as it has not been detected at infrared wavelengths (it has been seen in X-ray light).

    Magnetars are formed when a massive giant star ends its life in a supernova explosion, leaving behind a super dense neutron star with an incredibly strong magnetic field. The ring seen by Spitzer could not have formed during the original explosion, as any material as close to the star as the ring would have been disrupted by the supernova shock wave. Scientists suspect that the ring my actually be the edges of a bubble that was hollowed out by an explosive burst from the magnetar in 1998. The very bright region near the center of the image is a cluster of young stars, which may be illuminating the inner edge of the bubble, making it look like a ring in projection.

    This composite image was taken using all three of Spitzer's science instruments. The blue color represents 8-micron infrared light taken by the infrared array camera, green is 16-micron light from the infrared spectograph, and red is 24-micron radiation from the multiband imaging photometer.

  2. 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

  3. 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

  4. [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

  5. Lumbar instability: an evolving and challenging concept

    PubMed Central

    Beazell, James R; Mullins, Melise; Grindstaff, Terry L

    2010-01-01

    Identification and management of chronic lumbar spine instability is a clinical challenge for manual physical therapists. Chronic lumbar instability is presented as a term that can encompass two types of lumbar instability: mechanical (radiographic) and functional (clinical) instability (FLI). The components of mechanical and FLI are presented relative to the development of a physical therapy diagnosis and management. The purpose of this paper is to review the historical framework of chronic lumbar spine instability from a physical therapy perspective and to summarize current research relative to clinical diagnosis in physical therapy. PMID:21655418

  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. Radicular interdural lumbar disc herniation.

    PubMed

    Akhaddar, Ali; Boulahroud, Omar; Elasri, Abad; Elmostarchid, Brahim; Boucetta, Mohammed

    2010-07-01

    Intraradicular lumbar disc herniation is a rare complication of disc disease that is generally diagnosed only during surgery. The mechanism for herniated disc penetration into the intradural space is not known with certainty, but adhesion between the radicular dura and the posterior longitudinal ligament was suggested as the most important condition. The authors report the first case of an intraradicular lumbar disc herniation without subdural penetration; the disc hernia was lodged between the two radicular dura layers. The patient, a 34-year-old soldier, was admitted with a 12-month history of low back pain and episodic left sciatica. Neurologic examination showed a positive straight leg raising test on the left side without sensory, motor or sphincter disturbances. Spinal CT scan and MRI exploration revealed a left posterolateral osteophyte formation at the L5-S1 level with an irregular large disc herniation, which migrated superiorly. An intradural extension was suspected. A left L5 hemilaminectomy and S1 foraminotomy were performed. The exploration revealed a large fragment of disc material located between the inner and outer layers of the left S1 radicular dura. The mass was extirpated without cerebrospinal fluid outflow. The postoperative course was uneventful. Radicular interdural lumbar disc herniation should be suspected when a swollen, hard and immobile nerve root is present intraoperatively.

  8. 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

  9. 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.

  10. 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.

  11. [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.

  12. 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.

  13. 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

  14. 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

  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. [Pseudomeningocele following lumbar intervertebral disk surgery].

    PubMed

    Anagnostopoulus-Schleep, J; Krähling, K H; König, H J

    1987-01-01

    Pseudomeningoceles have been observed several times after closed traumatic injuries of the cervical plexus resulting in avulsion of the nerve roots. Following lumbar puncture or lumbar disc operation meningoceles are seldom occurring events. The first report of perineural cysts causing sciatic pain was made by Bancroft (1) in 1941. Since that time about 50 cases have been reviewed by the literature (10, 11). In this paper we report another case of an iatrogenic pseudomeningocele developed following surgical treatment for herniated lumbar disc attempting to outline their clinical and radiological findings.

  17. Lumbar hernia: a short historical survey.

    PubMed

    Cavallaro, Antonino; De Toma, Giorgio; Cavallaro, Giuseppe

    2012-01-01

    Lumbar hernia is a rare form of abdominal hernia, which has been recognized later along the early development of the modern surgery. it has been, on many occasions, the object of heavy debate regarding its anatomical background and as well its etiology. The authors reports the historical aspects of this rare pathology, focusing on the earliest descriptions of hernia arising in lumbar regions, on the first reports of surgical repair, and on the anatomical description of the lumbar weakness areas, that are currently named Petit's triangle and Grynfeltt and Lesshaft's triangle.

  18. 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

  19. [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

  20. MR imaging of lumbar arachnoiditis.

    PubMed

    Ross, J S; Masaryk, T J; Modic, M T; Delamater, R; Bohlman, H; Wilbur, G; Kaufman, B

    1987-11-01

    To assess the usefulness of MR in defining the changes of lumbar arachnoiditis, we reviewed retrospectively the MR, plain-film myelographic, and CT myelographic findings in 100 patients referred for evaluation of failed-back-surgery syndrome. In 11 of 12 cases of arachnoiditis demonstrated by plain-film and CT myelography, an abnormal configuration of nerve roots was seen by MR. The correlated MR and CT and plain-film myelographic changes were divided into three anatomic groups: group 1 showed conglomerations of adherent roots residing centrally within the thecal sac, group 2 demonstrated roots adherent peripherally to the meninges giving rise to an "empty-sac" appearance, and group 3 demonstrated a soft-tissue mass replacing the subarachnoid space. There was one false-negative MR study. For the diagnosis of moderate to severe arachnoiditis, we found MR to correlate excellently with CT myelographic and plain-film myelographic findings.

  1. A new case of a LUMBAR syndrome.

    PubMed

    Golabi, Mahin; An, Andrew C; Lopez, Christina; Lee, Lauren; Kwong, Michael; Hall, Bryan D

    2014-01-01

    LUMBAR syndrome (lower body congenital infantile hemangiomas and other skin defects; urogenital anomalies and ulceration; myelopathy; bony deformities; anorectal malformations and arterial anomalies; and rectal anomalies) is a rare association between infantile hemangiomas of the lower half of the body and regional congenital anomalies. Since 1986, 53 cases have been reported and no etiology has been identified. We report on the 54th case in a male infant and review the literature concerning the manifestations of the LUMBAR syndrome.

  2. 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.

  3. 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.

  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. 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.

  6. 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

  7. The rings of Saturn

    NASA Technical Reports Server (NTRS)

    Pollack, J. B.

    1978-01-01

    Consideration is given to the development of theories concerning the rings of Saturn. Particular attention is given to ring structure, noting its thinness, the separations between rings, and observed variations in brightness. Data gathered via infrared, radio and radar techniques are described in terms of ring particle composition and size. Hypotheses about ring origin and evolution are outlined, including the tidal disruption model, calculations of Saturn's gravitational contraction history, grazing, and meteoroid bombardment. Prospects for future observations of Saturn's rings are reviewed, such as the variation in their radar reflectivity as a function of the tilt of the ring plane.

  8. 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.

  9. 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

  10. 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

  11. Minimally invasive procedures on the lumbar spine

    PubMed Central

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

    2015-01-01

    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. Activations of Deep Lumbar Stabilizing Muscles by Transcutaneous Neuromuscular Electrical Stimulation of Lumbar Paraspinal Regions

    PubMed Central

    Baek, Seung Ok; Ahn, Sang Ho; Jones, Rodney; Cho, Hee Kyung; Jung, Gil Su; Cho, Yun Woo

    2014-01-01

    Objective To investigate changes in lumbar multifidus (LM) and deep lumbar stabilizing abdominal muscles (transverse abdominis [TrA] and obliquus internus [OI]) during transcutaneous neuromuscular electrical stimulation (NMES) of lumbar paraspinal L4-L5 regions using real-time ultrasound imaging (RUSI). Methods Lumbar paraspinal regions of 20 healthy physically active male volunteers were stimulated at 20, 50, and 80 Hz. Ultrasound images of the LM, TrA, OI, and obliquus externus (OE) were captured during stimulation at each frequency. Results The thicknesses of superficial LM and deep LM as measured by RUSI were greater during NMES than at rest for all three frequencies (p<0.05). The thicknesses in TrA, OI, and OE were also significantly greater during NMES of lumbar paraspinal regions than at rest (p<0.05). Conclusion The studied transcutaneous NMES of the lumbar paraspinal region significantly activated deep spinal stabilizing muscle (LM) and the abdominal lumbar stabilizing muscles TrA and OI as evidenced by RUSI. The findings of this study suggested that transcutaneous NMES might be useful for improving spinal stability and strength in patients having difficulty initiating contraction of these muscles. PMID:25229029

  13. 49 CFR 572.115 - Lumbar spine and pelvis.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 7 2010-10-01 2010-10-01 false Lumbar spine and pelvis. 572.115 Section 572.115... 50th Percentile Male § 572.115 Lumbar spine and pelvis. The specifications and test procedure for the lumbar spine and pelvis are identical to those for the SID dummy as set forth in § 572.42 except that...

  14. 49 CFR 572.115 - Lumbar spine and pelvis.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 7 2011-10-01 2011-10-01 false Lumbar spine and pelvis. 572.115 Section 572.115... 50th Percentile Male § 572.115 Lumbar spine and pelvis. The specifications and test procedure for the lumbar spine and pelvis are identical to those for the SID dummy as set forth in § 572.42 except that...

  15. 49 CFR 572.115 - Lumbar spine and pelvis.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 7 2013-10-01 2013-10-01 false Lumbar spine and pelvis. 572.115 Section 572.115... 50th Percentile Male § 572.115 Lumbar spine and pelvis. The specifications and test procedure for the lumbar spine and pelvis are identical to those for the SID dummy as set forth in § 572.42 except that...

  16. 49 CFR 572.115 - Lumbar spine and pelvis.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 7 2014-10-01 2014-10-01 false Lumbar spine and pelvis. 572.115 Section 572.115... 50th Percentile Male § 572.115 Lumbar spine and pelvis. The specifications and test procedure for the lumbar spine and pelvis are identical to those for the SID dummy as set forth in § 572.42 except that...

  17. 49 CFR 572.115 - Lumbar spine and pelvis.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 7 2012-10-01 2012-10-01 false Lumbar spine and pelvis. 572.115 Section 572.115... 50th Percentile Male § 572.115 Lumbar spine and pelvis. The specifications and test procedure for the lumbar spine and pelvis are identical to those for the SID dummy as set forth in § 572.42 except that...

  18. Laparoscopic lumbar hernia repair in a child with lumbocostovertebral syndrome.

    PubMed

    Jones, Sarah L; Thomas, Iona; Hamill, James

    2010-02-01

    Lumbocostovertebral syndrome is the association of a congenital lumbar hernia with rib and vertebral anomalies. We report the first case of a laparoscopic repair of a lumbar hernia in a child with lumbocostovertebral syndrome. Laparoscopic lumbar hernia repair appears to be safe and feasible in children.

  19. 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.

  20. Traumatic lumbar hernia: report of a case.

    PubMed

    Torer, Nurkan; Yildirim, Sedat; Tarim, Akin; Colakoglu, Tamer; Moray, Gokhan

    2008-12-01

    Traumatic lumbar hernias are very rare. Here, we present a case of secondary lumbar hernia. A 44-year-old man sustained a crushing injury. On admission, ecchymotic, fluctuating swelling was present on his left flank with normal vital signs. Subcutaneous intestinal segments were revealed at his left flank on abdominal CT. Emergency laparotomy revealed a 10-cm defect on the left postero-lateral abdominal wall. The splenic flexure was herniated through the defect. Herniated segments was reduced, the defect was repaired with a polypropylene mesh graft. There was also a serosal tear and an ischemic area 3mm wide on the splenic flexure and was repaired primarily. The patient had an uneventful recovery. Most traumatic lumbar hernias are caused by blunt trauma. Trauma that causes abdominal wall disruption also may cause intraabdominal organ injury. Abdominal CT is useful in the diagnosis and allows for diagnosis of coexisting organ injury. Emergency laparotomy should be performed to repair possible coexisting injuries.

  1. Lumbar hernia repaired using a new technique.

    PubMed

    Di Carlo, Isidoro; Toro, Adriana; Sparatore, Francesca; Corsale, Giuseppe

    2007-01-01

    Lumbar hernia is uncommon and occurs in Grynfeltt's triangle on the left side, more frequently in men than in women. Acquired lumbar hernias are the result of iliac crest bone harvest or blunt trauma and seat belt injuries in road accidents. Many surgical options have been reported for repairing this hernia through primary closure of the defect or through use of aponeurotic or prosthetic materials. The Dowd technique is the technique most often used. The authors describe a patient with posttraumatic inferior triangle lumbar hernia who underwent laparoscopy and, 10 days later, laparotomy. Both procedures failed. Finally, a novel lumbotomic surgical approach was used, involving the Dowd technique and prosthetic mesh. The patient was free of recurrence 3 months after the procedure.

  2. Cervical Meningomyelitis After Lumbar Epidural Steroid Injection

    PubMed Central

    Kim, Joon-Sung; Kim, Ji Yeon

    2015-01-01

    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

  3. Diagnostic value of the lumbar extension-loading test in patients with lumbar spinal stenosis: a cross-sectional study

    PubMed Central

    2014-01-01

    Background The gait-loading test is a well known, important test with which to assess the involved spinal level in patients with lumbar spinal stenosis. The lumbar extension-loading test also functions as a diagnostic loading test in patients with lumbar spinal stenosis; however, its efficacy remains uncertain. The purpose of this study was to compare the diagnostic value of the lumbar extension-loading test with that of the gait-loading test in patients with lumbar spinal stenosis. Methods A total of 116 consecutive patients (62 men and 54 women) diagnosed with lumbar spinal stenosis were included in this cross-sectional study of the lumbar extension-loading test. Subjective symptoms and objective neurological findings (motor, sensory, and reflex) were examined before and after the lumbar extension-loading and gait-loading tests. The efficacy of the lumbar extension-loading test for establishment of a correct diagnosis of the involved spinal level was assessed and compared with that of the gait-loading test. Results There were no significant differences between the lumbar extension-loading test and the gait-loading test in terms of subjective symptoms, objective neurological findings, or changes in the involved spinal level before and after each loading test. Conclusions The lumbar extension-loading test is useful for assessment of lumbar spinal stenosis pathology and is capable of accurately determining the involved spinal level. PMID:25080292

  4. 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

  5. Neuromodulation of the lumbar spinal locomotor circuit.

    PubMed

    AuYong, Nicholas; Lu, Daniel C

    2014-01-01

    The lumbar spinal cord contains the necessary circuitry to independently drive locomotor behaviors. This function is retained following spinal cord injury (SCI) and is amenable to rehabilitation. Although the effectiveness of task-specific training and pharmacologic modulation has been repeatedly demonstrated in animal studies, results from human studies are less striking. Recently, lumbar epidural stimulation (EDS) along with locomotor training was shown to restore weight-bearing function and lower-extremity voluntary control in a chronic, motor-complete human SCI subject. Related animal studies incorporating EDS as part of the therapeutic regiment are also encouraging. EDS is emerging as a promising neuromodulatory tool for SCI. PMID:24262896

  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. Lumbar spinal extradural angiolipomas. Two case reports.

    PubMed

    Dogan, Seref; Arslan, Erhan; Sahin, Soner; Aksoy, Kaya; Aker, Sibel

    2006-03-01

    Spinal extradural angiolipomas are benign tumors mostly localized in the thoracic region. A 50-year-old woman and a 36-year-old man presented with rare lumbar spinal angiolipoma manifesting as low back pain but without neurological signs. Magnetic resonance imaging showed lumbar extradural tumors at the L4-5 and L1-2 levels, respectively. Each patient underwent complete surgical resection of the epidural tumors. Histological examination revealed characteristics of angiolipomas in both tumors. The symptoms of both patients improved postoperatively and no recurrence of the tumors was found 1 year after surgery.

  8. [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

  9. 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

  10. 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

  11. [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

  12. [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.

  13. Evolution of Design of Interbody Cages for Anterior Lumbar Interbody Fusion.

    PubMed

    Phan, Kevin; Mobbs, Ralph J

    2016-08-01

    Anterior lumbar interbody fusion (ALIF) is one of the surgical procedures for the relief of chronic back pain, radiculopathy and neurogenic claudication in patients with degenerative lumbar spine disease that is refractory to conservative therapy, low-grade spondylolisthesis and pseudo arthrosis. Over the past half century, both the surgical techniques and instrumentation required for ALIF have changed significantly. In particular, the designs of ALIF cage and the materials used have evolved dramatically, the common goal being to improve fusion rates and optimize clinical outcomes. The increasing popularity of ALIF is reflected by the increasing abundance of published studies reporting clinical outcomes, surgical techniques and grafting options for ALIF. Developments in cage designs include cylindrical Bagby and Kuslich, cylindrical ray, cylindrical mesh, lumbar-tapered, polyethyl-etherketone cage and integral fixation cages. Biologic implants include bone dowels and femoral ring allografts. Methods for optimization of cage design have included cage dimensions, use of novel composite cage materials and integral fixation technologies. However, the historical development and evolution of cages used for ALIF has not been extensively documented. This article therefore aims to provide an overview of the historical basis for the anterior approach, evolution in design of ALIF cage implants and potential future research directions. PMID:27627708

  14. 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

  15. Vascular ring (image)

    MedlinePlus

    Vascular ring is a term used to describe a number of abnormal formations of the aorta, the large artery ... the pulmonary artery. The abnormal vessel(s) forms a ring, which encircles and may press down on the ...

  16. 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

  17. 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.

  18. 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

  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. 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)

  1. 49 CFR 572.187 - Lumbar spine.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 7 2010-10-01 2010-10-01 false Lumbar spine. 572.187 Section 572.187 Transportation Other Regulations Relating to Transportation (Continued) NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) ANTHROPOMORPHIC TEST DEVICES 2re Side Impact Crash...

  2. 49 CFR 572.187 - Lumbar spine.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 7 2014-10-01 2014-10-01 false Lumbar spine. 572.187 Section 572.187 Transportation Other Regulations Relating to Transportation (Continued) NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) ANTHROPOMORPHIC TEST DEVICES ES-2re Side Impact...

  3. Chondromyxoid fibroma of the lumbar spine.

    PubMed

    Cabral, C E; Romano, S; Guedes, P; Nascimento, A; Nogueira, J; Smith, J

    1997-08-01

    A bulky tumor of the first lumbar vertebra is described. The case is the 21st to be reported. The tumor resembled an aneurysmal bone cyst radiologically. It was resected without incident. The previously reported cases are reviewed and the literature discussed. PMID:9297754

  4. 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

  5. 49 CFR 572.187 - Lumbar spine.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... freely to achieve an impact velocity of 6.05 ±0.1 m/s measured at the center of the pendulum accelerometer (Figure 22) at the time the pendulum makes contact with its decelerating mechanism. The velocity... to paragraph (b)—ES-2re Lumbar Spine Certification Pendulum Velocity Corridor Upper boundary...

  6. 49 CFR 572.187 - Lumbar spine.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... freely to achieve an impact velocity of 6.05 ±0.1 m/s measured at the center of the pendulum accelerometer (Figure 22) at the time the pendulum makes contact with its decelerating mechanism. The velocity... to paragraph (b)—ES-2re Lumbar Spine Certification Pendulum Velocity Corridor Upper boundary...

  7. 49 CFR 572.187 - Lumbar spine.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... freely to achieve an impact velocity of 6.05 ±0.1 m/s measured at the center of the pendulum accelerometer (Figure 22) at the time the pendulum makes contact with its decelerating mechanism. The velocity... to paragraph (b)—ES-2re Lumbar Spine Certification Pendulum Velocity Corridor Upper boundary...

  8. [Lumbar arachnoid cysts: 2 unusual cases].

    PubMed

    Mailleux, P; Dooms, G; Coulier, B; Malbecq, S

    1992-04-01

    Two cases of arachnoid cyst in the lumbar region are described. One is intradural, acquired, and associated to severe arachnoiditis while the other is extradural in location and probably congenital. The interest of myelography, CT myelography, and MRI for the diagnosis is discussed.

  9. Acute Sciatic Neuritis following Lumbar Laminectomy

    PubMed Central

    Hitchon, Patrick; Reddy, Chandan G.

    2014-01-01

    It is commonly accepted that the common cause of acute/chronic pain in the distribution of the lumbosacral nerve roots is the herniation of a lumbar intervertebral disc, unless proven otherwise. The surgical treatment of lumbar disc herniation is successful in radicular pain and prevents or limits neurological damage in the majority of patients. Recurrence of sciatica after a successful disc surgery can be due to many possible etiologies. In the clinical setting we believe that the term sciatica might be associated with inflammation. We report a case of acute sciatic neuritis presented with significant persistent pain shortly after a successful disc surgery. The patient is a 59-year-old female with complaint of newly onset sciatica after complete pain resolution following a successful lumbar laminectomy for acute disc extrusion. In order to manage the patient's newly onset pain, the patient had multiple pain management visits which provided minimum relief. Persistent sciatica and consistent physical examination findings urged us to perform a pelvic MRI to visualize suspected pathology, which revealed right side sciatic neuritis. She responded to the electrical neuromodulation. Review of the literature on sciatic neuritis shows this is the first case report of sciatic neuritis subsequent to lumbar laminectomy. PMID:25024708

  10. Partial facetectomy for lumbar foraminal stenosis.

    PubMed

    Kang, Kevin; Rodriguez-Olaverri, Juan Carlos; Schwab, Frank; Hashem, Jenifer; 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.

  11. 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.

  12. Complication avoidance and management in anterior lumbar interbody fusion.

    PubMed

    Than, Khoi D; Wang, Anthony C; Rahman, Shayan U; Wilson, Thomas J; Valdivia, Juan M; Park, Paul; La Marca, Frank

    2011-10-01

    The goal of this study was to review the literature to compare strategies for avoiding and treating complications from anterior lumbar interbody fusion (ALIF), and thus provide a comprehensive aid for spine surgeons. A thorough review of databases from the US National Library of Medicine and the National Institutes of Health was conducted. The complications of ALIF addressed in this paper include pseudarthrosis and subsidence, vascular injury, retrograde ejaculation, ileus, and lymphocele (chyloretroperitoneum). Strategies identified for improving fusion rates included the use of frozen rather than freeze-dried allograft, cage instrumentation, and bone morphogenetic protein. Lower cage heights appear to reduce the risk of subsidence. The most common vascular injury is venous laceration, which occurs less frequently when using nonthreaded interbody grafts such as iliac crest autograft or femoral ring allograft. Left iliac artery thrombosis is the most common arterial injury, and its occurrence can be minimized by intermittent release of retraction intraoperatively. The risk of retrograde ejaculation is significantly higher with laparoscopic approaches, and thus should be avoided in male patients. Despite precautionary measures, complications from ALIF may occur, but treatment options do exist. Bowel obstruction can be treated conservatively with neostigmine or with decompression. In cases of postoperative lymphocele, resolution can be attained by creating a peritoneal window. By recognizing ways to minimize complications, the spine surgeon can safely use ALIF procedures.

  13. 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

  14. Effects of lumbar stabilization exercise on functional disability and lumbar lordosis angle in patients with chronic low back pain.

    PubMed

    Cho, Igsoo; Jeon, Chunbae; Lee, Sangyong; Lee, Daehee; Hwangbo, Gak

    2015-06-01

    [Purpose] This study examined the effects of lumbar stabilization exercises on the functional disability and lumbar lordosis angles in patients with chronic low back pain. [Subjects] The subjects were 30 patients with chronic low back pain divided into a lumbar stabilization exercise group (n = 15) and a conservative treatment group (n = 15). [Methods] The lumbar stabilization exercise and conservative treatment groups performed an exercise program and conservative physical treatment, respectively. Both programs were performed 3 times a week for 6 weeks. The degree of functional disability was assessed by the Oswestry disability index, and lumbar lordosis angles were measured by plain radiography. [Results] The Oswestry disability index decreased significantly in the both groups; however, it was significantly lower in the lumbar stabilization exercise group. The lumbar lordosis angle increased significantly in the lumbar stabilization exercise group after treatment and was also significantly greater than that in the conservative treatment group. [Conclusion] Lumbar stabilization exercise is more effective than conservative treatment for improving functional disability and lumbar lordosis angles.

  15. On multiple Einstein rings

    NASA Astrophysics Data System (ADS)

    Werner, M. C.; An, J.; Evans, N. W.

    2008-12-01

    A number of recent surveys for gravitational lenses have found examples of double Einstein rings. Here, we analytically investigate the occurrence of multiple Einstein rings. We prove, under very general assumptions, that at the most one Einstein ring can arise from a mass distribution in a single plane lensing a single background source. Two or more Einstein rings can therefore only occur in multiplane lensing. Surprisingly, we show that it is possible for a single source to produce more than one Einstein ring. If two point masses, or two isothermal spheres, in different planes are aligned with observer and source on the optical axis, we show that there are up to three Einstein rings. We also discuss the image morphologies for these two models if axisymmetry is broken, and give the first instances of magnification invariants in the case of two-lens planes.

  16. 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.

  17. [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

  18. Single incision endoscopic surgery for lumbar hernia.

    PubMed

    Kawaguchi, Masahiko; Ishikawa, Norihiko; Shimizu, Satsuki; Shin, Hisato; Matsunoki, Aika; Watanabe, Go

    2011-01-01

    Single Incision Endoscopic Surgery (SIES) has emerged as a less invasive surgery among laparoscopic surgeries, and this approach for incisional hernia was reported recently. This is the first report of SIES for an incisional lumbar hernia. A 66-year-old Japanese woman was referred to our institution because of a left flank hernia that developed after left iliac crest bone harvesting. A 20-mm incision was created on the left side of the umbilicus and all three trocars (12, 5, and 5 mm) were inserted into the incision. The hernial defect was 14 × 9 cm and was repaired with intraperitoneal onlay mesh and a prosthetic graft. The postoperative course was uneventful. SIES for lumbar hernia offers a safe and effective outcome equivalent compared to laparoscopic surgery. In addition, SIES is less invasive and has a cosmetic benefit.

  19. [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.

  20. [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.

  1. The Effects of Stretching with Lumbar Traction on VAS and Oswestry Scales of Patients with Lumbar 4–5 Herniated Intervertebral Disc

    PubMed Central

    Yang, Hae-sun; Yoo, Won-gyu

    2014-01-01

    [Purpose] This study investigated the effect of stretching with lumbar traction on VAS and Oswestry scale scores of lumbar 4–5 herniated intervertebral disc (HIVD) patients. [Subjects] We recruited 20 lumbar 4–5 HIVD patients. [Methods] We performed stretching with lumbar traction for lumbar 4–5 HIVD patients during 4 weeks. The VAS and Oswestry scales were measured before and 4 weeks after the intervention. [Results] The results showed a significant decrease in VAS scale scores for stretching with lumbar traction in lumbar 4–5 HIVD patients, from 18±1.29 to 2.1±1.35. The Oswestry scale scores also decreased significantly, from 20.35±2.01 to 3.5±2.84, after stretching with lumbar traction. [Conclusion] Thus, we suggest stretching with lumbar traction for lumbar 4–5 HIVD patients. PMID:25140094

  2. Temperatures of Saturn's rings.

    NASA Technical Reports Server (NTRS)

    Murphy, R. E.

    1973-01-01

    The 20-micron brightness temperatures of the rings were determined using the 224-cm telescope of the Mauna Kea Observatory, and the standard University of Hawaii radiometer with a 17- to 25-micron filter. The observations were made on the nights of Aug. 20 and 21, and Sept. 26 and 27, 1972. The brightness temperatures of the A, B, and C rings are, respectively, 89 plus or minus 3 K, 94 plus or minus 2 K, and 89 plus or minus 4 K. A possible explanation of the relatively high temperature of the C ring is that Saturn has radiation belts and the inner ring is heated by particle bombardment.

  3. Lumbar hernia: surgical anatomy, embryology, and technique of repair.

    PubMed

    Stamatiou, Dimitrios; Skandalakis, John E; Skandalakis, Lee J; Mirilas, Petros

    2009-03-01

    Lumbar hernia is the protrusion of intraperitoneal or extraperitoneal contents through a defect of the posterolateral abdominal wall. Barbette was the first, in 1672, to suggest the existence of lumbar hernias. The first case was reported by Garangeot in 1731. Petit and Grynfeltt delineated the boundaries of the inferior and superior lumbar triangles in 1783 and 1866, respectively. These two anatomical sites account for about 95 per cent of lumbar hernias. Approximately 20 per cent of lumbar hernias are congenital. The rest are either primarily or secondarily acquired. The most common cause of primarily acquired lumbar hernias is increased intra-abdominal pressure. Secondarily acquired lumbar hernias are associated with prior surgical incisions, trauma, and abscess formation. During embryologic development, weakening of the area of the aponeuroses of the layered abdominal muscles that derive from somitic mesoderm, which invades the somatopleure, may potentially lead to lumbar hernias. Repair of lumbar hernias should be performed as early as possible to avoid incarceration and strangulation. The classic repair technique uses the open approach, where closure of the defect is performed either directly or using prosthetic mesh. The laparoscopic approach, either transabdominal or extraperitoneal, is an alternative.

  4. 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.

  5. Congenitally absent lumbar pedicle: a reappraisal

    SciTech Connect

    Wortzman, G.; Steinhardt, M.I.

    1984-09-01

    Three patients who had a diagnosis of congenitally absent lumbar pedicle underwent CT examination. Findings showed that each patient had an aberrant hypoplastic pedicle plus a retroisthmic defect in their ipsilateral lamina rather than an absent pedicle. Axial CT was the diagnostic modality of choice; reformated images were of little value. The differential diagnosis to be considered from the findings of plain film radiography includes pediculate thinning, neoplastic disease, neurofibroma, mesodermal dysplasia associated with neurofibromatosis, and vascular anomalies.

  6. 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

  7. 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

  8. Subarachnoid hemorrhage due to retained lumbar drain.

    PubMed

    Guppy, Kern H; Silverthorn, James W; Akins, Paul T

    2011-12-01

    Intrathecal spinal catheters (lumbar drains) are indicated for several medical and surgical conditions. In neurosurgical procedures, they are used to reduce intracranial and intrathecal pressures by diverting CSF. They have also been placed for therapeutic access to administer drugs, and more recently, vascular surgeons have used them to improve spinal cord perfusion during the treatment of thoracic aortic aneurysms. Insertion of these lumbar drains is not without attendant complications. One complication is the shearing of the distal end of the catheter with a resultant retained fragment. The authors report the case of a 65-year-old man who presented with a subarachnoid hemorrhage due to the migration of a retained lumbar drain that sheared off during its removal. To the best of the authors' knowledge, this is the first case of rostral migration of a retained intrathecal catheter causing subarachnoid hemorrhage. The authors review the literature on retained intrathecal spinal catheters, and their findings support either early removal of easily accessible catheters or close monitoring with serial imaging.

  9. 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).

  10. 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

  11. Comparison of percutaneous endoscopic lumbar discectomy and open lumbar surgery for adjacent segment degeneration and recurrent disc herniation.

    PubMed

    Chen, Huan-Chieh; Lee, Chih-Hsun; Wei, Li; Lui, Tai-Ngar; Lin, Tien-Jen

    2015-01-01

    Objective. The goal of the present study was to examine the clinical results of percutaneous endoscopic lumbar discectomy (PELD) and open lumbar surgery for patients with adjacent segment degeneration (ASD) and recurrence of disc herniation. Methods. From December 2011 to November 2013, we collected forty-three patients who underwent repeated lumbar surgery. These patients, either received PELD (18 patients) or repeated open lumbar surgery (25 patients), due to ASD or recurrence of disc herniation at L3-4, L4-5, or L5-S1 level, were assigned to different groups according to the surgical approaches. Clinical data were assessed and compared. Results. Mean blood loss was significantly less in the PELD group as compared to the open lumbar surgery group (P < 0.0001). Hospital stay and mean operating time were shorter significantly in the PELD group as compared to the open lumbar surgery group (P < 0.0001). Immediate postoperative pain improvement in VAS was 3.5 in the PELD group and -0.56 in the open lumbar surgery group (P < 0.0001). Conclusion. For ASD and recurrent lumbar disc herniation, PELD had more advantages over open lumbar surgery in terms of reduced blood loss, shorter hospital stay, operating time, fewer complications, and less postoperative discomfort.

  12. Evaluation of ABM/P-15 versus autogenous bone in an ovine lumbar interbody fusion model.

    PubMed

    Sherman, Blake P; Lindley, Emily M; Turner, A Simon; Seim, Howard B; Benedict, James; Burger, Evalina L; Patel, Vikas V

    2010-12-01

    A prospective, randomized study was performed in an ovine model to compare the efficacy of an anorganic bovine-derived hydroxyapatite matrix combined with a synthetic 15 amino acid residue (ABM/P-15) in facilitating lumbar interbody fusion when compared with autogenous bone harvested from the iliac crest. P-15 is a biomimetic to the cell-binding site of Type-I collagen for bone-forming cells. When combined with ABM, it creates the necessary scaffold to initiate cell invasion, binding, and subsequent osteogenesis. In this study, six adult ewes underwent anterior-lateral interbody fusion at L3/L4 and L4/L5 using PEEK interbody rings filled with autogenous bone at one level and ABM/P-15 at the other level and no additional instrumentation. Clinical CT scans were obtained at 3 and 6 months; micro-CT scans and histomorphometry analyses were performed after euthanization at 6 months. Clinical CT scan analysis showed that all autograft and ABM/P-15 treated levels had radiographically fused outside of the rings at the 3-month study time point. Although the clinical CT scans of the autograft treatment group showed significantly better fusion within the PEEK rings than ABM/P-15 at 3 months, micro-CT scans, clinical CT scans, and histomorphometric analyses showed there were no statistical differences between the two treatment groups at 6 months. Thus, ABM/P-15 was as successful as autogenous bone graft in producing lumbar spinal fusion in an ovine model, and it should be further evaluated in clinical studies.

  13. 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

  14. 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

  15. Tadpole system as new lumbar spinal instrumentation

    PubMed Central

    Kasai, Yuichi; Inaba, Tadashi; Akeda, Koji; Uchida, Atsumasa

    2008-01-01

    Background There have been reports of serious complications associated with pedicle screw fixation, including nerve root injuries caused by accidental screw insertion. We have developed a new system of lumbar spinal instrumentation that we call Tadpole system®. The purposes of this report were to show the results of a biomechanical study and the short-term outcome of a clinical study, as well as to determine the usefulness of this system. Methods The Tadpole system® lumbar spinal fusion is a hook-and-rod system according to which the spine is stabilized using 2 sets of 2 spinous processes each that are held in place by 4 hooks tandemly connected to a rod. The biomechanical study was done using 5 human lumbar cadaveric spines, and the range of motion (ROM) was examined in a non-treatment model, an injured model, a pedicle screw fixation model and a Tadpole system® model. For the short-term clinical study the Tadpole system® was used in 31 patients, and the factors analyzed were operation time, time required for spinal instrumentation, amount of intraoperative bleeding, postoperative improvement rate of the Japanese Orthopaedic Association (JOA) score for lumbar spinal disorders, instrumentation failure, spinous process fracture, spinal fluid leakage, nerve root injury, postoperative infection, and bone fusion 2 years after the operation. Results The ROM in the Tadpole system® model was slightly bigger than that in the pedicle screw fixation model, but smaller than that in the normal control model. These biomechanical data indicated that the Tadpole system® provided fairly good stability. The mean operation time was 79 min, the mean time required for spinal instrumentation was 8 min, and the mean amount of intraoperative bleeding was 340 mL. The mean postoperative improvement rate of JOA score was 70.9 ± 24.8%. Instrumentation failure (dislocation of a hook) occurred in one patient, and none of the patients developed spinous process fracture, spinal fluid

  16. 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

  17. Lumbar Disk Herniation Surgery: Outcome and Predictors

    PubMed Central

    Sedighi, Mahsa; Haghnegahdar, Ali

    2014-01-01

    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

  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. 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 ...

  20. 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)

  1. 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.

  2. Smoke Ring Physics

    NASA Astrophysics Data System (ADS)

    Huggins, Elisha

    2011-11-01

    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 Ampère's law in an introductory physics course. We discuss these common features.

  3. Vertebrae numbers of the early hominid lumbar spine.

    PubMed

    Haeusler, Martin; Martelli, Sandra A; Boeni, Thomas

    2002-11-01

    General doctrine holds that early hominids possessed a long lumbar spine with six segments. This is mainly based on Robinson's (1972) interpretation of a single partial Australopithecus africanus skeleton, Sts 14, from Sterkfontein, South Africa. As its sixth last presacral vertebra exhibits both thoracic and lumbar characteristics, current definitions of lumbar vertebrae and lumbar ribs are discussed in the present study. A re-analysis of its entire preserved vertebral column and comparison with Stw 431, another partial A. africanus skeleton from Sterkfontein, and the Homo erectus skeleton KNM-WT 15000 from Nariokotome, Kenya, did not provide strong evidence for the presence of six lumbar vertebrae in either of these early hominids. Thus, in Sts 14 the sixth last presacral vertebra has on one side a movable rib. In Stw 431, the corresponding vertebra shows indications for a rib facet. In KNM-WT, 15000 the same element is very fragmentary, but the neighbouring vertebrae do not support the view that it is L1. Although in all three fossils the transitional vertebra at which the articular facets change orientation seems to be at Th11, this is equal to a large percentage of modern humans. Indeed, a modal number of five lumbar vertebrae, as in modern humans, is more compatible with evolutionary principles. For example, six lumbar vertebrae would require repetitive shortening and lengthening not only of the lumbar, but also of the entire precaudal spine. Furthermore, six lumbar vertebrae are claimed to be biomechanically advantageous for early hominid bipedalism, yet an explanation is lacking as to why the lumbar region should have shortened in later humans. All this raises doubts about previous conclusions for the presence of six lumbar vertebrae in early hominids. The most parsimonious explanation is that they did not differ from modern humans in the segmentation of the vertebral column.

  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. 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

  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. 49 CFR 572.43 - Lumbar spine and pelvis.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 7 2013-10-01 2013-10-01 false Lumbar spine and pelvis. 572.43 Section 572.43... Percentile Male § 572.43 Lumbar spine and pelvis. (a) When the pelvis of a fully assembled dummy (SA-SID... section, the peak acceleration at the location of the accelerometer mounted in the pelvis cavity...

  10. 49 CFR 572.43 - Lumbar spine and pelvis.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 7 2011-10-01 2011-10-01 false Lumbar spine and pelvis. 572.43 Section 572.43... Percentile Male § 572.43 Lumbar spine and pelvis. (a) When the pelvis of a fully assembled dummy (SA-SID... section, the peak acceleration at the location of the accelerometer mounted in the pelvis cavity...

  11. 49 CFR 572.43 - Lumbar spine and pelvis.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 7 2012-10-01 2012-10-01 false Lumbar spine and pelvis. 572.43 Section 572.43... Percentile Male § 572.43 Lumbar spine and pelvis. (a) When the pelvis of a fully assembled dummy (SA-SID... section, the peak acceleration at the location of the accelerometer mounted in the pelvis cavity...

  12. 49 CFR 572.43 - Lumbar spine and pelvis.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 7 2014-10-01 2014-10-01 false Lumbar spine and pelvis. 572.43 Section 572.43... Percentile Male § 572.43 Lumbar spine and pelvis. (a) When the pelvis of a fully assembled dummy (SA-SID... section, the peak acceleration at the location of the accelerometer mounted in the pelvis cavity...

  13. 49 CFR 572.43 - Lumbar spine and pelvis.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 7 2010-10-01 2010-10-01 false Lumbar spine and pelvis. 572.43 Section 572.43... Percentile Male § 572.43 Lumbar spine and pelvis. (a) When the pelvis of a fully assembled dummy (SA-SID... section, the peak acceleration at the location of the accelerometer mounted in the pelvis cavity...

  14. 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

  15. Hot piston ring tests

    NASA Astrophysics Data System (ADS)

    Allen, David J.; Tomazic, William A.

    1987-12-01

    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.

  16. Dynamics of narrow rings

    NASA Technical Reports Server (NTRS)

    Dermott, S. F.

    1984-01-01

    The ring models described here were developed to account for the dynamical problems posed by the narrow rings of Uranus. Some of these rings are now known to be eccentric, inclined, nonuniform in width, optically thick, and narrow, with very sharp edges. The eccentric rings have common pericenters and large, positive eccentricity gradients. The theory of shepherding satellites successfully accounts for most of these features and can also account for some features of the narrow Saturnian rings, in particular, waves, kinks, and periodic variations in brightness. Outstanding problems include the putative relation between eccentricity and inclination displayed by eight of the nine Uranian rings, and the magnitudes of the tidal torques acting on the shepherding satellites. The horseshoe-orbit model, although viable, probably has more application to the narrow rings from which the Saturnian coorbital satellites formed. The angular momentum flow rate due to particle collisions is a minimum at the Lagrangian equilibrium points L(4) and L(5), and one can expect accretion to be rapid at these points.

  17. 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.

  18. 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.

  19. 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

  20. 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.

  1. 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.

  2. 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.

  3. 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

  4. 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.

  5. Highlights in planetary rings

    NASA Astrophysics Data System (ADS)

    Porco, Carolyn C.

    1995-07-01

    There is a rich phenomenology within the planetary rings surrounding the giant planets, most of it discovered by the Voyagers during their historic tours of t he outer solar system in the 1980s. In the last decade, there have been two detailed IUGG reviews of planetary rings. Cuzzi [1983] covered the time period from 1979-1983 which included the Pioneer 11 encounter with Saturn (1979), the Voyager 1 and 2 encounters with Jupiter (1979) and with Saturn (1980 and 1981). Nicholson and Dones [1991] reviewed the developments in the field between 1984 and 1991, a period of time which included the Voyager 2 Uranus (1986) and Neptune (1989) encounters. (References t o additional reviews of planetary rings and related fields can be found in Nicholson and Dones [1991].) Rather than being comprehensive in nature, this review will concentrate on only those areas of ring research in which particularly promising developments have occurred in the last half decade.

  6. 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.

  7. 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.

  8. Ultrasonic Newton's rings

    SciTech Connect

    Hsu, D.K. ); Dayal, V. )

    1992-03-09

    Interference fringes due to bondline thickness variation were observed in ultrasonic scans of the reflected echo amplitude from the bondline of adhesively joined aluminum skins. To demonstrate that full-field interference patterns are observable in point-by-point ultrasonic scans, an optical setup for Newton's rings was scanned ultrasonically in a water immersion tank. The ultrasonic scan showed distinct Newton's rings whose radii were in excellent agreement with the prediction.

  9. Nardo Ring, Italy

    NASA Technical Reports Server (NTRS)

    2008-01-01

    The Nardo Ring is a striking visual feature from space, and astronauts have photographed it several times. The Ring is a race car test track; it is 12.5 kilometers long and steeply banked to reduce the amount of active steering needed by drivers. The Nardo Ring lies in a remote area on the heel of Italy's 'boot,' 50 kilometers east of the naval port of Taranto. The Ring encompasses a number of active (green) and fallow (brown to dark brown) agricultural fields. In this zone of intensive agriculture, farmers gain access to their fields through the Ring via a series of underpasses. Winding features within the southern section of the Ring appear to be smaller, unused race tracks.

    The image covers an area of 18.8 x 16.4 km, was acquired on August 17. 2007, and is located at 49.3 degrees north latitude, 17.8 degrees east longitude.

    The U.S. science team is located at NASA's Jet Propulsion Laboratory, Pasadena, Calif. The Terra mission is part of NASA's Science Mission Directorate.

  10. 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.

  11. 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

  12. 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

  13. 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

  14. 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

  15. 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

  16. 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

  17. 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

  18. 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

  19. Postoperative seizure following transforaminal percutaneous endoscopic lumbar discectomy

    PubMed Central

    Kertmen, Hayri; Gürer, Bora; Yilmaz, Erdal Resit; Sekerci, Zeki

    2016-01-01

    Endoscopic surgery for lumbar disc herniation has been available for more than 30 years. Transforaminal percutaneous endoscopic lumbar discectomy is a well-known, safe, and effective method used for the treatment of the lumbar disc herniation. The published complications of the transforaminal percutaneous endoscopic lumbar discectomy consist of infections, thrombophlebitis, dysesthesia, dural tear, vascular injury, and death. Seizure after transforaminal percutaneous endoscopic lumbar discectomy is an extremely rare complication. A 20-year-old patient applied at our department who had undergone transforaminal percutaneous endoscopic lumbar. During the procedure, while performing the discography, non-ionic contrast media was administered into the thecal sac inadvertently. Two hours after surgery, the patient developed generalized tonic-clonic seizure of 5-min duration. Diagnosis of iohexol-induced seizure was made and the patient was treated supportively without anti-epileptics. Here we present the first case of seizure after transforaminal percutaneous endoscopic lumbar discectomy, which was caused by inadvertent administration of the contrast media into the thecal sac.

  20. Postoperative seizure following transforaminal percutaneous endoscopic lumbar discectomy

    PubMed Central

    Kertmen, Hayri; Gürer, Bora; Yilmaz, Erdal Resit; Sekerci, Zeki

    2016-01-01

    Endoscopic surgery for lumbar disc herniation has been available for more than 30 years. Transforaminal percutaneous endoscopic lumbar discectomy is a well-known, safe, and effective method used for the treatment of the lumbar disc herniation. The published complications of the transforaminal percutaneous endoscopic lumbar discectomy consist of infections, thrombophlebitis, dysesthesia, dural tear, vascular injury, and death. Seizure after transforaminal percutaneous endoscopic lumbar discectomy is an extremely rare complication. A 20-year-old patient applied at our department who had undergone transforaminal percutaneous endoscopic lumbar. During the procedure, while performing the discography, non-ionic contrast media was administered into the thecal sac inadvertently. Two hours after surgery, the patient developed generalized tonic-clonic seizure of 5-min duration. Diagnosis of iohexol-induced seizure was made and the patient was treated supportively without anti-epileptics. Here we present the first case of seizure after transforaminal percutaneous endoscopic lumbar discectomy, which was caused by inadvertent administration of the contrast media into the thecal sac. PMID:27695562

  1. 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

  2. Dynamic stabilization for degenerative spondylolisthesis and lumbar spinal instability.

    PubMed

    Ohtonari, Tatsuya; Nishihara, Nobuharu; Suwa, Katsuyasu; Ota, Taisei; Koyama, Tsunemaro

    2014-01-01

    Lumbar interbody fusion is a widely accepted surgical procedure for patients with lumbar degenerative spondylolisthesis and lumbar spinal instability in the active age group. However, in elderly patients, it is often questionable whether it is truly necessary to construct rigid fixation for a short period of time. In recent years, we have been occasionally performing posterior dynamic stabilization in elderly patients with such lumbar disorders. Posterior dynamic stabilization was performed in 12 patients (6 women, 70.9 ± 5.6 years old at the time of operation) with lumbar degenerative spondylolisthesis in whom % slip was less than 20% or instability associated with lumbar disc herniation between March 2011 and March 2013. Movement occurs through the connector linked to the pedicle screw. In practice, 9 pairs of D connector system where the rod moves in the perpendicular direction alone and 8 pairs of Dynamic connector system where the connector linked to the pedicle screw rotates in the sagittal direction were installed. The observation period was 77-479 days, and the mean recovery rate of lumbar Japanese Orthopedic Association (JOA) score was 65.6 ± 20.8%. There was progression of slippage due to slight loosening in a case with lumbar degenerative spondylolisthesis, but this did not lead to exacerbation of the symptoms. Although follow-up was short, there were no symptomatic adjacent vertebral and disc disorders during this period. Posterior dynamic stabilization may diminish the development of adjacent vertebral or disc disorders due to lumbar interbody fusion, especially in elderly patients, and it may be a useful procedure that facilitates decompression and ensures a certain degree of spinal stabilization.

  3. Adjacent level disease following lumbar spine surgery: A review

    PubMed Central

    Epstein, Nancy E.

    2015-01-01

    Background: Instrumented lumbar spine surgery is associated with an increased risk of adjacent segment disease (ASD). Multiple studies have explored the various risk factors contributing to ASD that include; fusion length (especially, three or more levels), sagittal malalignment, facet injury, advanced age, and prior cephalad degenerative disease. Methods: In this selective review of ASD, following predominantly instrumented fusions for lumbar degenerative disease, patients typically underwent open versus minimally invasive surgery (MIS), transforaminal lumbar interbody fusions (TLIFs), posterior lumbar interbody fusions (PLIFs), or rarely posterolateral lumbar instrumented or noninstrumented fusions (posterolateral lumbar fusion). Results: The incidence of ASD, following open or MI lumbar instrumented fusions, ranged up to 30%; notably, the addition of instrumentation in different series did not correlate with improved outcomes. Alternatively, in one series, at 164 postoperative months, noninstrumented lumbar fusions reduced the incidence of ASD to 5.6% versus 18.5% for ASD performed with instrumentation. Of interest, dynamic instrumented/stabilization techniques did not protect patients from ASD. Furthermore, in a series of 513 MIS TLIF, there was a 15.6% incidence of perioperative complications that included; a 5.1% frequency of durotomy and a 2.3% instrumentation failure rate. Conclusions: The incidence of postoperative ASD (up to 30%) is greater following either open or MIS instrumented lumbar fusions (e.g., TLIF/PLIF), while decompressions with noninstrumented fusions led to a much smaller 5.6% risk of ASD. Other findings included: MIS instrumented fusions contributed to higher perioperative complication rates, and dynamic stabilization did not protect against ASD. PMID:26693387

  4. Retaining-Ring Installation Tool

    NASA Technical Reports Server (NTRS)

    Christian, S.

    1983-01-01

    New tool eliminates damage to ring through improper tool use. Tool installs spiral-wound retaining rings quickly, reliably, and safely. Tool inserts rings in splined or irregularly shaped bores, bores at bottom of deep ring and slides it along bore until it nests in groove. Pistons are moved by variety of linkages.

  5. 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.

  6. 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.

  7. Traumatic lumbar hernia: can't afford to miss.

    PubMed

    Saboo, Sachin S; Khurana, Bharti; Desai, Naman; Juan, Yu-Hsiang; Landman, Wendy; Sodickson, Aaron; Gates, Jonathan

    2014-06-01

    We describe the radiological and surgical correlation of an uncommon case of a traumatic lumbar hernia in a 22-year-old man presenting to the emergency department following a motor vehicle accident. Computed tomography (CT) of the abdomen revealed a right-sided traumatic inferior lumbar hernia containing a small amount of fat through the posterior lateral internal oblique muscle with hematoma in the subcutaneous fat and adjacent abdominal wall musculature, which was repaired surgically via primary closure on emergent basis. The purpose of this article is to emphasize the importance of diagnosing traumatic lumbar hernia on CT and need for urgent repair to avoid potential complications of bowel incarceration and strangulation.

  8. Thermodynamic black di-rings

    SciTech Connect

    Iguchi, Hideo; Mishima, Takashi

    2010-10-15

    Previously the five dimensional S{sup 1}-rotating black rings have been superposed in a concentric way by some solitonic methods, and regular systems of two S{sup 1}-rotating black rings were constructed by the authors and then Evslin and Krishnan (we called these solutions 'black di-rings'). In this place we show some characteristics of the solutions of five dimensional black di-rings, especially in thermodynamic equilibrium. After the summary of the di-ring expressions and their physical quantities, first we comment on the equivalence of the two different solution sets of the black di-rings. Then the existence of thermodynamic black di-rings is shown, in which both isothermality and isorotation between the inner black ring and the outer black ring are realized. We also give detailed analysis of peculiar properties of the thermodynamic black di-ring including discussion about a certain kind of thermodynamic stability (instability) of the system.

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

    PubMed

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

    2015-12-01

    [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.

  10. 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

  11. Propellers in Saturn's rings

    NASA Astrophysics Data System (ADS)

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

    2013-12-01

    Theoretical studies and simulations have demonstrated the effects caused by objects embedded in planetary rings. 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 (~<500m in size) have been indirectly identified in Saturn's A ring through their propeller signature in the images. Furthermore, recent Cassini observations indicate the possible existence of objects embedded even in Saturn's B and C ring. In this paper we present evidence for the existence of propellers in Saturn's B ring by combining data from Cassini Ultraviolet Imaging Spectrograph (UVIS) and Imaging Science Subsystem (ISS) experiments. We show evidence that B ring seems to harbor two distinct populations of propellers: "big" propellers covering tens of degrees in azimuth situated in the densest part of B ring, and "small" propellers in less dense inner B ring that are similar in size and shape to known A ring propellers. The population of "big" propellers is exemplified with a single object which is observed for 5 years of Cassini data. The object is seen as a very elongated bright stripe (40 degrees wide) in unlit Cassini images, and dark stripe in lit geometries. In total we report observing the feature in images at 18 different epochs between 2005 and 2010. In UVIS occultations we observe this feature as an optical depth depletion in 14 out of 93 occultation cuts at corrotating longitudes compatible with imaging data. Combining the available Cassini data we infer that the object is a partial gap located at r=112,921km embedded in the high optical depth region of the B

  12. 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.

  13. 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

  14. 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.

  15. 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.

  16. Two F Ring Views

    NASA Technical Reports Server (NTRS)

    2005-01-01

    These views, taken two hours apart, demonstrate the dramatic variability in the structure of Saturn's intriguing F ring.

    In the image at the left, ringlets in the F ring and Encke Gap display distinctive kinks, and there is a bright patch of material on the F ring's inner edge. Saturn's moon Janus (181 kilometers, or 113 miles across) is shown here, partly illuminated by reflected light from the planet.

    At the right, Prometheus (102 kilometers, or 63 miles across) orbits ahead of the radial striations in the F ring, called 'drapes' by scientists. The drapes appear to be caused by successive passes of Prometheus as it reaches the greatest distance (apoapse) in its orbit of Saturn. Also in this image, the outermost ringlet visible in the Encke Gap displays distinctive bright patches.

    These views were obtained from about three degrees below the ring plane.

    The images were taken in visible light with the Cassini spacecraft narrow-angle camera on June 29, 2005, when Cassini was about 1.5 million kilometers (900,000 miles) from Saturn. The image scale is about 9 kilometers (6 miles) per pixel.

  17. 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

  18. 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

  19. 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

  20. 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

  1. 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)

  2. 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

  3. Double Ring Craters

    NASA Technical Reports Server (NTRS)

    1974-01-01

    A faint double ring crater is seen at upper right in this picture of Mercury (FDS 166601) taken one hour and 40 minutes before Mariner 10's second rendezvous with the planet September 21. Located 35 degrees S. Lat. The outer ring is 170 kilometers (10 miles) across. Double ring craters are common features on Mercury. This particular feature and the bright rayed crater to its left were seen from a different viewing angle in pictures taken by Mariner 10 during its first Mercury flyby last March 29.

    The Mariner 10 mission, managed by the Jet Propulsion Laboratory for NASA's Office of Space Science, explored Venus in February 1974 on the way to three encounters with Mercury-in March and September 1974 and in March 1975. The spacecraft took more than 7,000 photos of Mercury, Venus, the Earth and the Moon.

    Image Credit: NASA/JPL/Northwestern University

  4. 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

  5. Oligomeric ferrocene rings

    NASA Astrophysics Data System (ADS)

    Inkpen, Michael S.; Scheerer, Stefan; Linseis, Michael; White, Andrew J. P.; Winter, Rainer F.; Albrecht, Tim; Long, Nicholas J.

    2016-09-01

    Cyclic oligomers comprising strongly interacting redox-active monomer units represent an unknown, yet highly desirable class of nanoscale materials. Here we describe the synthesis and properties of the first family of molecules belonging to this compound category—differently sized rings comprising only 1,1‧-disubstituted ferrocene units (cyclo[n], n = 5-7, 9). Due to the close proximity and connectivity of centres (covalent Cp-Cp linkages; Cp = cyclopentadienyl) solution voltammograms exhibit well-resolved, separated 1e- waves. Theoretical interrogations into correlations based on ring size and charge state are facilitated using values of the equilibrium potentials of these transitions, as well as their relative spacing. As the interaction free energies between the redox centres scale linearly with overall ring charge and in conjunction with fast intramolecular electron transfer (˜107 s-1), these molecules can be considered as uniformly charged nanorings (diameter ˜1-2 nm).

  6. Oligomeric ferrocene rings

    NASA Astrophysics Data System (ADS)

    Inkpen, Michael S.; Scheerer, Stefan; Linseis, Michael; White, Andrew J. P.; Winter, Rainer F.; Albrecht, Tim; Long, Nicholas J.

    2016-09-01

    Cyclic oligomers comprising strongly interacting redox-active monomer units represent an unknown, yet highly desirable class of nanoscale materials. Here we describe the synthesis and properties of the first family of molecules belonging to this compound category—differently sized rings comprising only 1,1‧-disubstituted ferrocene units (cyclo[n], n = 5–7, 9). Due to the close proximity and connectivity of centres (covalent Cp–Cp linkages; Cp = cyclopentadienyl) solution voltammograms exhibit well-resolved, separated 1e– waves. Theoretical interrogations into correlations based on ring size and charge state are facilitated using values of the equilibrium potentials of these transitions, as well as their relative spacing. As the interaction free energies between the redox centres scale linearly with overall ring charge and in conjunction with fast intramolecular electron transfer (∼107 s‑1), these molecules can be considered as uniformly charged nanorings (diameter ∼1–2 nm).

  7. Child sex rings.

    PubMed

    Wild, N J; Wynne, J M

    1986-07-19

    Details of 11 child sex rings identified in one working class community were obtained by interviewing investigating police officers and examining health and social services records. The rings contained 14 adult male perpetrators and 175 children aged 6-15 years. Most perpetrators used child ringleaders to recruit victims; others became a "family friend" or obtained a position of authority over children. Secrecy was encouraged and bribery, threats, and peer pressure used to induce participation in sexual activities. Offences reported included fondling, masturbation, pornography, and oral, vaginal, and anal intercourse. Eleven perpetrators were successfully prosecuted; all but one received a sentence of three years or less. Behavioural problems were common among those children who had participated for a long time. Child sex rings are difficult to detect and may be common. Many children are seriously abused as a consequence of them. PMID:3730803

  8. 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.

  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. Ring laser gyroscope anode

    SciTech Connect

    Ljung, B.H.

    1981-03-17

    An anode for a ring laser gyroscope which provides improved current stability in the glow discharge path is disclosed. The anode of this invention permits operation at lower currents thereby allowing a reduction of heat dissipation in the ring laser gyroscope. The anode of one embodiment of this invention is characterized by a thumbtack appearance with a spherical end where the normal sharp end of the thumbtack would be located. The stem of the anode extends from the outside of the gyroscope structure to the interior of the structure such that the spherical end is substantially adjacent to the laser beam.

  11. The covariant chiral ring

    NASA Astrophysics Data System (ADS)

    Bourget, Antoine; Troost, Jan

    2016-03-01

    We construct a covariant generating function for the spectrum of chiral primaries of symmetric orbifold conformal field theories with N = (4 , 4) supersymmetry in two dimensions. For seed target spaces K3 and T 4, the generating functions capture the SO(21) and SO(5) representation theoretic content of the chiral ring respectively. Via string dualities, we relate the transformation properties of the chiral ring under these isometries of the moduli space to the Lorentz covariance of perturbative string partition functions in flat space.

  12. GUARD RING SEMICONDUCTOR JUNCTION

    DOEpatents

    Goulding, F.S.; Hansen, W.L.

    1963-12-01

    A semiconductor diode having a very low noise characteristic when used under reverse bias is described. Surface leakage currents, which in conventional diodes greatly contribute to noise, are prevented from mixing with the desired signal currents. A p-n junction is formed with a thin layer of heavily doped semiconductor material disposed on a lightly doped, physically thick base material. An annular groove cuts through the thin layer and into the base for a short distance, dividing the thin layer into a peripheral guard ring that encircles the central region. Noise signal currents are shunted through the guard ring, leaving the central region free from such currents. (AEC)

  13. Unidirectional ring lasers

    DOEpatents

    Hohimer, John P.; Craft, David C.

    1994-01-01

    Unidirectional ring lasers formed by integrating nonreciprocal optical elements into the resonant ring cavity. These optical elements either attenuate light traveling in a nonpreferred direction or amplify light traveling in a preferred direction. In one preferred embodiment the resonant cavity takes the form of a circle with an S-shaped crossover waveguide connected to two points on the interior of the cavity such that light traveling in a nonpreferred direction is diverted from the cavity into the crossover waveguide and reinjected out of the other end of the crossover waveguide into the cavity as light traveling in the preferred direction.

  14. Unidirectional ring lasers

    DOEpatents

    Hohimer, J.P.; Craft, D.C.

    1994-09-20

    Unidirectional ring lasers formed by integrating nonreciprocal optical elements into the resonant ring cavity is disclosed. These optical elements either attenuate light traveling in a nonpreferred direction or amplify light traveling in a preferred direction. In one preferred embodiment the resonant cavity takes the form of a circle with an S-shaped crossover waveguide connected to two points on the interior of the cavity such that light traveling in a nonpreferred direction is diverted from the cavity into the crossover waveguide and reinjected out of the other end of the crossover waveguide into the cavity as light traveling in the preferred direction. 21 figs.

  15. Saturn's Rings, the Yarkovsky Effects, and the Ring of Fire

    NASA Technical Reports Server (NTRS)

    Rubincam, David Parry

    2004-01-01

    The dimensions of Saturn's A and B rings may be determined by the seasonal Yarkovsky effect and the Yarkovsky-Schach effect; the two effects confine the rings between approximately 1.68 and approximately 2.23 Saturn radii, in reasonable agreement with the observed values of 1.525 and 2.267. The C ring may be sparsely populated because its particles are transients on their way to Saturn; the infall may create a luminous Ring of Fire around Saturn's equator. The ring system may be young: in the past heat flow from Saturn's interior much above its present value would not permit rings to exist.

  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.

  17. 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

  18. 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

  19. 49 CFR 572.19 - Lumbar spine, abdomen and pelvis.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... rotation joints by the attachments shown in Figure 18. Tighten the mountings so that the pelvis-lumbar joining surface is horizontal and adjust the femur ball-flange screws at each hip socket joint to 50...

  20. 49 CFR 572.19 - Lumbar spine, abdomen and pelvis.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... rotation joints by the attachments shown in Figure 18. Tighten the mountings so that the pelvis-lumbar joining surface is horizontal and adjust the femur ball-flange screws at each hip socket joint to 50...

  1. 49 CFR 572.19 - Lumbar spine, abdomen and pelvis.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... rotation joints by the attachments shown in Figure 18. Tighten the mountings so that the pelvis-lumbar joining surface is horizontal and adjust the femur ball-flange screws at each hip socket joint to 50...

  2. 49 CFR 572.19 - Lumbar spine, abdomen and pelvis.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... rotation joints by the attachments shown in Figure 18. Tighten the mountings so that the pelvis-lumbar joining surface is horizontal and adjust the femur ball-flange screws at each hip socket joint to 50...

  3. 49 CFR 572.19 - Lumbar spine, abdomen and pelvis.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... rotation joints by the attachments shown in Figure 18. Tighten the mountings so that the pelvis-lumbar joining surface is horizontal and adjust the femur ball-flange screws at each hip socket joint to 50...

  4. 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. PMID:27579204

  5. Laparoscopic tension-free hernioplasty for lumbar hernia.

    PubMed

    Maeda, K; Kanehira, E; Shinno, H; Yamamura, K

    2003-09-01

    Lumbar hernia, a defect of the posterior abdominal wall, is a very rare condition. The repair of a posterior abdominal wall hernia by simply closing the hernia port with sutures may not be adequate, especially when the herniation is due to a weakness in the abdominal wall. Recently, a simple, logical method of tension-free repair has become a popular means for the treatment of various abdominal wall hernias. Previous studies have advocated the use of tension-free repair for lumbar hernia; the technique uses a mesh replacement and requires an extensive incision. Herein we present a case of superior lumbar hernia. Our technique consisted of a laparoscopic tension-free hernioplasty with the application of a Prolene mesh. This technique, which provides an excellent operative view, is safe, feasible, and minimally invasive. We conclude that laparoscopic tension-free repair should be the preferred option for the treatment of lumbar hernia.

  6. Diagnosis of Lumbar Foraminal Stenosis using Diffusion Tensor Imaging.

    PubMed

    Eguchi, Yawara; 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

    2016-02-01

    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.

  7. 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

  8. The acute lumbar disc herniation: imaging diagnosis.

    PubMed

    Yussen, P S; Swartz, J D

    1993-12-01

    The acute lumbar herniated nucleus pulposus (HNP) can often be diagnosed on good quality MRI or CT examination. Myelography, discography, and postmyelography/postdiscography CT ordinarily are reserved for equivocal and protracted cases. MRI is recommended as the initial study of choice except for older patients for whom CT may be more valuable because of the high incidence of osteophytosis. Patients with acute herniated nucleus pulposus (HNP) may have varied clinical symptoms depending on the level of the HNP, extent of the annulus tear/depth of penetration of nuclear material, and the direction of the disc herniation. HNP does not necessarily produce radiculopathy and may cause vague low back pain. This article reviews and analyzes the clinical symptoms and problems associated with HNP, as well as the pitfalls and differential diagnostic possibilities in interpretation. PMID:8297631

  9. Automatic CT Measurement In Lumbar Vertebrae

    NASA Astrophysics Data System (ADS)

    Bisseling, Johannes T.; van Erning, Leon J. T. O.; Schouten, Theo E.; Lemmen, J. Albert M.

    1989-04-01

    Reliable software for automatic determination of the border between the cancellous bone and the cortical bone of lumbar vertebrae has been developed. An automatic procedure is needed because calculations in a larger series of patient data take too much time due to the inevitable human interaction required by available software packages. Processing in batch mode is essential. An important advantage of automatic outlining is its reproducibility, because only a single technique with objective criteria is used. In a so-called Region Of Interest (ROI) texture analysis can be performed to quantify the condition of the vertebral body in order to diagnose osteoporosis. This technique may be an alternative to a classification based solely on the average X-ray absorption value.

  10. Methodologic evaluation of the lumbar disc syndrome.

    PubMed Central

    Robinson, J. S.

    1981-01-01

    Though the lumbar disc syndrome is a costly and ubiquitous affliction, effective evaluation of the disease process has been confounded by major unaddressed methodological short falls. Prominent difficulties include: inattention to the clinical boundaries of the syndrome, neglected co-morbid disease processes, comparison of unequal treatment groups and premature clinical data extrapolation, inadequate diagnostic validation, variability in surgical observation, and reliance upon follow-up techniques faulted by unaddressed distorting factors. Proposals for improvement include: formulation of suitable stratification subgroups emphasizing age and sign-symptom intensity and duration, techniques for improved diagnostic return from surgical exploration, suggestions toward improved quantitation of clinical testing procedures, and implantation of a quality of life scale. PMID:6454306

  11. 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

  12. Adjacent Segment Pathology after Lumbar Spinal Fusion

    PubMed Central

    Lee, Jae Chul

    2015-01-01

    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

  13. [Lumbar myelography with metrizamid (author's transl)].

    PubMed

    Kehler, M

    1977-03-01

    A series of lumbar myelographies -- 105 in 98 patients - was carried out with water-soluble Metrizamid (Amipaque R) in a concentration of 170 mg I/ml and showed side-effects in 32% and a quality of contrast similar to that of other water-soluble contrast media used before. The side effects were mild, of short duration and needed no treatment. There were no epileptic fits, tonic or clonic carried out 1 - 12 months later showed no signs of arachnoiditis. Dangers of more serious complications appeared to increase, the higher the level of injection into the spinal canal. A short survey of contrast media used in myelography and earlier experience of experimental or clinical side effects caused by Medtrizamid in myelography follows.

  14. Sciatica caused by lumbar epidural gas.

    PubMed

    Belfquih, Hatim; El Mostarchid, Brahim; Akhaddar, Ali; gazzaz, Miloudi; Boucetta, Mohammed

    2014-01-01

    Gas production as a part of disc degeneration can occur but rarely causes nerve compression syndromes. The clinical features are similar to those of common sciatica. CT is very useful in the detection of epidural gas accumulation and nerve root compression. We report a case of symptomatic epidural gas accumulation originating from vacuum phenomenon in the intervertebral disc, causing lumbo-sacral radiculopathy. A 45-year-old woman suffered from sciatica for 9 months. The condition worsened in recent days. Computed tomography (CT) demonstrated intradiscal vacuum phenomenon, and accumulation of gas in the lumbar epidural space compressing the dural sac and S1 nerve root. After evacuation of the gas, her pain resolved without recurrence.

  15. [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

  16. Chronic Osteomyelitis of the Lumbar Transverse Process

    PubMed Central

    Lee, Bong-Jin; Yoon, Min Geun; Kim, Sung-Soo; Moon, Myung-Sang

    2011-01-01

    Pyogenic spondylitis involving only the posterior element of a vertebra is rare. To the best of our knowledge, there have been no reports of osteomyelitis of the transverse process. We report here on a 45-year-old male with a one month history of swelling associated with lower back pain. The magnetic resonance imaging showed a paraspinal soft tissue mass, and computed tomography revealed a fine osteolytic lesion in the right transverse process of the 5th lumbar spine, and this was all consistent with chronic osteomyelitis. A mixed staphylococcal infection was identified. Open drainage, resection of the transverse process and intravenous injection of anti-staphylococcal antibiotics resolved the back pain and reduced the erythrocyte sedimentation rate to normal. Pyogenic osteomyelitis of the transverse process is extremely rare, which can cause a misdiagnosis or a delayed diagnosis. Careful consideration of this disease is needed when evaluating patients who complain of back pain. PMID:21909475

  17. 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

  18. Clinical Outcomes of Posterior Lumbar Interbody Fusion versus Minimally Invasive Transforaminal Lumbar Interbody Fusion in Three-Level Degenerative Lumbar Spinal Stenosis

    PubMed Central

    Fan, Guoxin; Wu, Xinbo; Yu, Shunzhi; Sun, Qi; Zhang, Hailong; Gu, Xin

    2016-01-01

    The aim of this study was to directly compare the clinical outcomes of posterior lumbar interbody fusion (PLIF) and minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) in three-level lumbar spinal stenosis. This retrospective study involved a total of 60 patients with three-level degenerative lumbar spinal stenosis who underwent MIS-TLIF or PLIF from January 2010 to February 2012. Back and leg visual analog scale (VAS), Oswestry Disability Index (ODI), and Short Form-36 (SF-36) scale were used to assess the pain, disability, and health status before surgery and postoperatively. In addition, the operating time, estimated blood loss, and hospital stay were also recorded. There were no significant differences in back VAS, leg VAS, ODI, SF-36, fusion condition, and complications at 12-month follow-up between the two groups (P > 0.05). However, significantly less blood loss and shorter hospital stay were observed in MIS-TLIF group (P < 0.05). Moreover, patients undergoing MIS-TLIF had significantly lower back VAS than those in PLIF group at 6-month follow-up (P < 0.05). Compared with PLIF, MIS-TLIF might be a prior option because of noninferior efficacy as well as merits of less blood loss and quicker recovery in treating three-level lumbar spinal stenosis. PMID:27747244

  19. Prediscovery evidence of planetary rings

    NASA Technical Reports Server (NTRS)

    Mclaughlin, W. I.

    1980-01-01

    The discoveries of the Uranian and Jovian ring systems were surprising events to most of the scientific community. However, as far back as 1787 reports of observations of rings about a planet other than Saturn were made; Herschel, the discoverer of Uranus, thought he had detected rings about that planet on several occasions. Although Herschel's observations were almost certainly due to defects in the optical system of his telescope, several valid observations and predictions have been made in the last two hundred years. This paper focuses on such prediscovery evidence for the Uranian and Jovian rings and for the newly designated F ring of Saturn. Some new work of the author on the structure of the Saturnian rings is included which is relevant to the F ring. The prospects for rings about Neptune and Pluto and a ring close to the Sun are also reviewed. The relevance of the prediscovery evidence to aspects of scientific methodology is discussed.

  20. Deformation Measurement Of Lumbar Vertebra By Holographic Interferometry

    NASA Astrophysics Data System (ADS)

    Matsumoto, Toshiro; Kojima, Arata; Ogawa, Ryoukei; Iwata, Koichi; Nagata, Ryo

    1988-01-01

    The mechanical properties of normal lumbar vertebra and one with the interarticular part cut off to simulate hemi-spondylolysis were measured by the double exposure holographic interferometry. In the normal lumbar vertebra, displacement due to the load applied to the inferior articular process was greater than that of superior articular process under the same load. The interarticular part was subjected to the high stress. From these points, one of the valuable data to consider the cause of spondylolysis was obtained.

  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. Laparoscopic repair of left lumbar hernia after laparoscopic left nephrectomy.

    PubMed

    Gagner, Michel; 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.

  3. 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

  4. Radiographic Morphometry of the Lumbar Spine in Munich Miniature Pigs.

    PubMed

    Engelke, Elisabeth C; Post, Christina; Pfarrer, Christiane D; Sager, Martin; Waibl, Helmut R

    2016-01-01

    The incidence of human spinal column disease remains high, and animal models still play important roles in prophylactic, diagnostic, and therapeutic research. Because of their similar size to humans, pigs remain an important spine model. For pigs to serve as a model for the human spine, basic similarities and differences must be understood. In this study, morphometric data of the lumbar spine of Munich miniature pigs (Troll) were recorded radiologically, evaluated, and compared with recorded human data. Whereas humans have a constant number of 5 lumbar vertebrae, Munich minipigs had 5 or 6 lumbar vertebrae. Compared with their human counterparts, the lumbar vertebral bodies of the minipigs were remarkably larger in the craniocaudal (superior-inferior) direction and considerably smaller in the dorsoventral and laterolateral directions. The porcine vertebral canal was smaller than the human vertebral canal. The spinal cord extended into the caudal part of the porcine lumbar vertebral canal and thus did not terminate as cranial, as seen in humans. The lumbar intervertebral spaces of the pig were narrower in craniocaudal direction than human intervertebral spaces. These differences need to be considered when planning surgical actions, not only to avoid pain and irreversible damage to the minipigs but also to achieve accurate scientific results. PMID:27177570

  5. Outcomes of Instrumented and Noninstrumented Posterolateral Lumbar Fusion.

    PubMed

    Pourtaheri, Sina; Billings, Charles; Bogatch, Michael; Issa, Kimona; Haraszti, Christopher; Mangel, Daniel; Lord, Elizabeth; Park, Howard; Ajiboye, Remi; Ashana, Adedayo; Emami, Arash

    2015-12-01

    The purpose of this study was to evaluate the long-term clinical and radiographic outcomes of posterolateral lumbar fusion for lumbar stenosis cases requiring bilateral facetectomy in conjunction with a laminectomy. The authors evaluated 34 consecutive patients who had undergone a lumbar laminectomy, bilateral partial facetectomy, and posterolateral fusion at a single institution between 1981 and 1996. They included 25 men and 9 women with a mean age of 42 years (range, 27-57 years). Twenty-three cases were instrumented and 11 were noninstrumented. Mean follow-up was 21 years (range, 15-29 years). Outcomes evaluated included reoperation rate, clinical outcomes evaluated by the Oswestry Disability Index (ODI) score, radiographic evaluations of adjacent segmental degeneration (ASD) and lumbar lordosis, and contributing demographic factors to disease progression. At final follow-up, 17 of the 34 patients had undergone reoperation (43% of the instrumented group and 64% of the noninstrumented group). There were no differences in the reoperation rate or ODI improvement between the instrumented and noninstrumented groups (P>.05). Female patients required more revisions, had less ODI improvement, had greater postoperative ASD, and had less maintenance of their postoperative lumbar lordosis. There was no difference in maintenance of postoperative lumbar lordosis or ASD between the instrumented and noninstrumented groups. Instrumentation did not improve revision rates, clinical outcomes, or radiographic outcomes in laminectomies requiring contemporaneous facetectomies. PMID:26652331

  6. Flushing Ring for EDM

    NASA Technical Reports Server (NTRS)

    Earwood, L.

    1985-01-01

    Removing debris more quickly lowers cutting time. Operation, cutting oil and pressurized air supplied to ring placed around workpiece. Air forces oil through small holes and agitates oil as it flows over workpiece. High flow rate and agitation dislodge and remove debris. Electrical discharge removes material from workpiece faster.

  7. Ring of Stellar Death

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This false-color image from NASA's Spitzer Space Telescope shows a dying star (center) surrounded by a cloud of glowing gas and dust. Thanks to Spitzer's dust-piercing infrared eyes, the new image also highlights a never-before-seen feature -- a giant ring of material (red) slightly offset from the cloud's core. This clumpy ring consists of material that was expelled from the aging star.

    The star and its cloud halo constitute a 'planetary nebula' called NGC 246. When a star like our own Sun begins to run out of fuel, its core shrinks and heats up, boiling off the star's outer layers. Leftover material shoots outward, expanding in shells around the star. This ejected material is then bombarded with ultraviolet light from the central star's fiery surface, producing huge, glowing clouds -- planetary nebulas -- that look like giant jellyfish in space.

    In this image, the expelled gases appear green, and the ring of expelled material appears red. Astronomers believe the ring is likely made of hydrogen molecules that were ejected from the star in the form of atoms, then cooled to make hydrogen pairs. The new data will help explain how planetary nebulas take shape, and how they nourish future generations of stars.

    This image composite was taken on Dec. 6, 2003, by Spitzer's infrared array camera, and is composed of images obtained at four wavelengths: 3.6 microns (blue), 4.5 microns (green), 5.8 microns (orange) and 8 microns (red).

  8. Reading, Writing, and Rings!

    ERIC Educational Resources Information Center

    Aschbacher, Pamela; Li, Erika; Hammon, Art

    2008-01-01

    "Reading, Writing, and Rings!" was created by a team of elementary teachers, literacy experts, and scientists in order to integrate science and literacy. These free units bring students inside NASA's Cassini-Huygens mission to Saturn. The authors--a science teacher and education outreach specialist and two evaluators of educational programs--have…

  9. Ring laser scatterometer

    SciTech Connect

    Ackermann, Mark; Diels, Jean-Claude

    2005-06-28

    A scatterometer utilizes the dead zone resulting from lockup caused by scatter from a sample located in the optical path of a ring laser at a location where counter-rotating pulses cross. The frequency of one pulse relative to the other is varied across the lockup dead zone.

  10. Making Molecular Borromean Rings

    ERIC Educational Resources Information Center

    Pentecost, Cari D.; Tangchaivang, Nichol; Cantrill, Stuart J.; Chichak, Kelly S.; Peters, Andrea J.; Stoddart, Fraser J.

    2007-01-01

    A procedure that requires seven 4-hour blocks of time to allow undergraduate students to prepare the molecular Borromean rings (BRs) on a gram-scale in 90% yield is described. The experiment would serve as a nice capstone project to culminate any comprehensive organic laboratory course and expose students to fundamental concepts, symmetry point…

  11. Neptune may have polar rings

    NASA Astrophysics Data System (ADS)

    Dobrovolskis, A. R.; Steiman-Cameron, T. Y.; Borderies, N. J.

    1989-08-01

    Perturbations from Neptune's highly inclined satellite Triton can maintain rings passing nearly over Neptune's poles. These hypothetical polar rings are nearly perpendicular to Triton's orbit as well, and lie within several degrees of the plane of Voyager II's trajectory through the Neptunian system. Polar rings can coexist with equatorial rings at different radii. A randomly oriented torus of debris around Neptune has a probability of several percent to settle into a polar ring. Voyager II stands a significant chance of encountering a polar ring.

  12. Narrow rings - Observations and theory

    NASA Astrophysics Data System (ADS)

    Porco, C. C.

    Voyager 1 and 2 observations have revealed that within the rings of Saturn lies a set of narrow, eccentric rings resembling those of Uranus. Voyager 2 observations have proven crucial in refining the Uranian ring orbit models to a remarkable level of precision. All these rings share some common structural and kinematical characteristics, such as spatially variable radial widths and uniform precession; however, interesting differences exist which provoke attention and may be related to the differing dynamical environments in which these rings dwell. The current state of the knowledge of the shape, behavior, and confinement of narrow rings is discussed.

  13. Ring Bubbles of Dolphins

    NASA Technical Reports Server (NTRS)

    Shariff, Karim; Marten, Ken; Psarakos, Suchi; White, Don J.; Merriam, Marshal (Technical Monitor)

    1996-01-01

    The article discusses how dolphins create and play with three types of air-filled vortices. The underlying physics is discussed. Photographs and sketches illustrating the dolphin's actions and physics are presented. The dolphins engage in this behavior on their own initiative without food reward. These behaviors are done repeatedly and with singleminded effort. The first type is the ejection of bubbles which, after some practice on the part of the dolphin, turn into toroidal vortex ring bubbles by the mechanism of baroclinic torque. These bubbles grow in radius and become thinner as they rise vertically to the surface. One dolphin would blow two in succession and guide them to fuse into one. Physicists call this a vortex reconnection. In the second type, the dolphins first create an invisible vortex ring in the water by swimming on their side and waving their tail fin (also called flukes) vigorously. This vortex ring travels horizontally in the water. The dolphin then turns around, finds the vortex and injects a stream of air into it from its blowhole. The air "fills-out" the core of the vortex ring. Often, the dolphin would knock-off a smaller ring bubble from the larger ring (this also involves vortex reconnection) and steer the smaller ring around the tank. One other dolphin employed a few other techniques for planting air into the fluke vortex. One technique included standing vertically in the water with tail-up, head-down and tail piercing the free surface. As the fluke is waved to create the vortex ring, air is entrained from above the surface. Another technique was gulping air in the mouth, diving down, releasing air bubbles from the mouth and curling them into a ring when they rose to the level of the fluke. In the third type, demonstrated by only one dolphin, the longitudinal vortex created by the dorsal fin on the back is used to produce 10-15 foot long helical bubbles. In one technique she swims in a curved path. This creates a dorsal fin vortex since

  14. Rings from Close Encounters

    NASA Astrophysics Data System (ADS)

    Kohler, Susanna

    2016-09-01

    Weve recently discovered narrow sets of rings around two minor planets orbiting in our solar system. How did these rings form? A new study shows that they could be a result of close encounters between the minor planets and giants like Jupiter or Neptune.Unexpected Ring SystemsPositions of the centaurs in our solar system (green). Giant planets (red), Jupiter trojans (grey), scattered disk objects (tan) and Kuiper belt objects (blue) are also shown. [WilyD]Centaurs are minor planets in our solar system that orbit between Jupiter and Neptune. These bodies of which there are roughly 44,000 with diameters larger than 1 km have dynamically unstable orbits that cross paths with those of one or more giant planets.Recent occultation observations of two centaurs, 10199 Chariklo and 2060 Chiron, revealed that these bodies both host narrow ring systems. Besides our four giant planets, Chariklo and Chiron are the only other bodies in the solar system known to have rings. But how did these rings form?Scientists have proposed several models, implicating collisions, disruption of a primordial satellite, or dusty outgassing. But a team of scientists led by Ryuki Hyodo (Paris Institute of Earth Physics, Kobe University) has recently proposed an alternative scenario: what if the rings were formed from partial disruption of the centaur itself, after it crossed just a little too close to a giant planet?Tidal Forces from a GiantHyodo and collaborators first used past studies of centaur orbits to estimate that roughly 10% of centaurs experience close encounters (passing within a distance of ~2x the planetary radius) with a giant planet during their million-year lifetime. The team then performed a series of simulations of close encounters between a giant planet and a differentiated centaur a body in which the rocky material has sunk to form a dense silicate core, surrounded by an icy mantle.Some snapshots of simulation outcomes (click for a closer look!) for different initial states of

  15. Comparison of trunk and hip muscle activity during different degrees of lumbar and hip extension.

    PubMed

    Kim, Sang-Min; Yoo, Won-Gyu

    2015-09-01

    [Purpose] This study compared the activity of trunk and hip muscles during different degrees of lumbar and hip extension. [Subjects] The study enrolled 18 participants. [Methods] Two exercises (hip and lumbar extension) and two ranges (180° and <180°) were studied. [Results] Differences in degree of extension affected the percentage maximal voluntary isometric contraction of the lumbar erector spinae and biceps femoris muscles, with significantly higher average values at >180° than at 180° lumbar extension. No significant differences were found in gluteus maximus activity according to exercise type or range. [Conclusion] Hip extension may be more effective and safer for lumbar rehabilitation than lumbar extension.

  16. Saturn ring temperature changes before and after ring equinox

    NASA Astrophysics Data System (ADS)

    Spilker, Linda; Flandes, Alberto; Morishima, Ryuji; Leyrat, Cedric; Altobelli, Nicolas; Ferrari, Cecile; Brooks, Shawn; Pilorz, Stu

    2010-05-01

    The Cassini Composite infrared spectrometer (CIRS) retrieved the temperatures of Saturn's main rings at solar elevations ranging from 24 degrees to zero degrees at equinox (August 2009) as the sun traversed from the south to north side of the rings. Over this broad range of solar elevation the CIRS data show that the ring temperatures vary as much as 29K- 38K for the A ring, 22K-34K for the B ring and 18K-23K for the C ring. Interestingly the unlit sides of the rings show a similar decrease in temperature with the decreasing solar elevation. As equinox approached, the main rings cooled to their lowest temperatures measured to date. At equinox the solar input is very small and the primary heat sources for the rings are Saturn thermal and visible energy. Temperatures are almost identical for similar geometries on the north and south sides of the rings. The ring temperatures at equinox were: C ring, 55-75 K; B ring, 45-60 K; Cassini Division, 45 - 58 K; and A ring, 43 - 52 K. After Saturn equinox the solar elevation angle began to increase again and the temperatures on both the lit (north) and unlit (south) sides of the rings have begun to increase as well. Ring thermal models developed by Flandes and Morishima are able to reproduce most of the equinox temperatures observed by CIRS. Results before and after equinox will be presented. This research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA and at CEA Saclay supported by the "Programme National de Planetologie". Copyright 2010 California Institute of Technology. Government sponsorship acknowledged.

  17. 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.

  18. 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

  19. Inorganic glass ceramic slip rings

    NASA Technical Reports Server (NTRS)

    Glossbrenner, E. W.; Cole, S. R.

    1972-01-01

    Prototypes of slip rings have been fabricated from ceramic glass, a material which is highly resistant to deterioration due to high temperature. Slip ring assemblies were not structurally damaged by mechanical tests and performed statisfactorily for 200 hours.

  20. 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

  1. O-Ring-Testing Fixture

    NASA Technical Reports Server (NTRS)

    Turner, James E.; Mccluney, D. Scott

    1990-01-01

    Fixture used to evalute properties of O-rings of various materials. Hydraulic actuator positions plug in housing, creating controlled, variable gap in O-ring glands formed by grooves in plug and by inner wall of housing. Creates controlled axial and radial gaps between sealing surfaces around ring so effectiveness of material in maintaining seal determined under dynamic conditions.

  2. RINGED ACCRETION DISKS: EQUILIBRIUM CONFIGURATIONS

    SciTech Connect

    Pugliese, D.; Stuchlík, Z. E-mail: zdenek.stuchlik@physics.cz

    2015-12-15

    We investigate a model of a ringed accretion disk, made up by several rings rotating around a supermassive Kerr black hole attractor. Each toroid of the ringed disk is governed by the general relativity hydrodynamic Boyer condition of equilibrium configurations of rotating perfect fluids. Properties of the tori can then be determined by an appropriately defined effective potential reflecting the background Kerr geometry and the centrifugal effects. The ringed disks could be created in various regimes during the evolution of matter configurations around supermassive black holes. Therefore, both corotating and counterrotating rings have to be considered as being a constituent of the ringed disk. We provide constraints on the model parameters for the existence and stability of various ringed configurations and discuss occurrence of accretion onto the Kerr black hole and possible launching of jets from the ringed disk. We demonstrate that various ringed disks can be characterized by a maximum number of rings. We present also a perturbation analysis based on evolution of the oscillating components of the ringed disk. The dynamics of the unstable phases of the ringed disk evolution seems to be promising in relation to high-energy phenomena demonstrated in active galactic nuclei.

  3. DC-Powered Jumping Ring

    ERIC Educational Resources Information Center

    Jeffery, Rondo N.; Farhang, Amiri

    2016-01-01

    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…

  4. Vortex Rings in Superfluid Helium

    NASA Astrophysics Data System (ADS)

    Alamri, Sultan Z.; Barenghi, Carlo F.

    2008-11-01

    We present results of numerical simulations of large-scale vortex rings in superfluid helium. These large-scale vortex rings consists of many discrete (quantized) vortex filaments which interact with each other moving according to the Biot-Savart law. Lifetime, structural stability and speed of large-scale vortex rings will be discussed and compared to experimental results.

  5. Uranus: the rings are black.

    PubMed

    Sinton, W M

    1977-11-01

    An upper limit of 0.05 is established for the geometric albedo of the newly discovered rings of Uranus. In view of this very low albedo, the particles of the rings cannot be ice-covered as are those of rings A and B of Saturn.

  6. 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.

  7. Satellite Rings Movie

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This brief movie clip (of which the release image is a still frame), taken by NASA's Cassini spacecraft as it approached Jupiter, shows the motions, over a 16 hour-period, of two satellites embedded in Jupiter's ring. The moon Adrastea is the fainter of the two, and Metis the brighter. Images such as these will be used to refine the orbits of the two bodies.

    The movie was made from images taken during a 40-hour sequence of the Jovian ring on December 11, 2000.

    Cassini is a cooperative mission of NASA, the European Space Agency and the Italian Space Agency. JPL, a division of the California Institute of Technology in Pasadena, manages Cassini for NASA's Office of Space Science, Washington, D.C.

  8. Oligomeric ferrocene rings.

    PubMed

    Inkpen, Michael S; Scheerer, Stefan; Linseis, Michael; White, Andrew J P; Winter, Rainer F; Albrecht, Tim; Long, Nicholas J

    2016-09-01

    Cyclic oligomers comprising strongly interacting redox-active monomer units represent an unknown, yet highly desirable class of nanoscale materials. Here we describe the synthesis and properties of the first family of molecules belonging to this compound category-differently sized rings comprising only 1,1'-disubstituted ferrocene units (cyclo[n], n = 5-7, 9). Due to the close proximity and connectivity of centres (covalent Cp-Cp linkages; Cp = cyclopentadienyl) solution voltammograms exhibit well-resolved, separated 1e(-) waves. Theoretical interrogations into correlations based on ring size and charge state are facilitated using values of the equilibrium potentials of these transitions, as well as their relative spacing. As the interaction free energies between the redox centres scale linearly with overall ring charge and in conjunction with fast intramolecular electron transfer (∼10(7) s(-1)), these molecules can be considered as uniformly charged nanorings (diameter ∼1-2 nm). PMID:27554408

  9. Which Ringed Planet...!?

    NASA Astrophysics Data System (ADS)

    2002-12-01

    Don't worry - you are not the only one who thought this was a nice amateur photo of planet Saturn, Lord of the Rings in our Solar System! But then the relative brightness and positions of the moons may appear somewhat unfamiliar... and the ring system does look unusually bright when compared to the planetary disk...?? Well, it is not Saturn, but Uranus , the next giant planet further out, located at a distance of about 3,000 million km, or 20 times the distance between the Sun and the Earth. The photo shows Uranus surrounded by its rings and some of the moons, as they appear on a near-infrared image that was obtained in the K s -band (at wavelength 2.2 µm) with the ISAAC multi-mode instrument on the 8.2-m VLT ANTU telescope at the ESO Paranal Observatory (Chile) . The exposure was made on November 19, 2002 (03:00 hrs UT) during a planetary research programme. The observing conditions were excellent (seeing 0.5 arcsec) and the exposure lasted 5 min. The angular diameter of Uranus is about 3.5 arcsec. The observers at ISAAC were Emmanuel Lellouch and Thérése Encrenaz of the Observatoire de Paris (France) and Jean-Gabriel Cuby and Andreas Jaunsen (both ESO-Chile). The rings The rings of Uranus were discovered in 1977, from observations during a stellar occultation event by astronomer teams at the Kuiper Airborne Observatory (KAO) and the Perth Observatory (Australia). Just before and after the planet moved in front of the (occulted) star, the surrounding rings caused the starlight to dim for short intervals of time. Photos obtained from the Voyager-2 spacecraft in 1986 showed a multitude of very tenuous rings. These rings are almost undetectable from the Earth in visible light. However, on the present VLT near-infrared picture, the contrast between the rings and the planet is strongly enhanced. At the particular wavelength at which this observation was made, the infalling sunlight is almost completely absorbed by gaseous methane present in the planetary atmosphere

  10. Double perforators-based superior gluteal artery propeller flap for reconstruction of lumbar defects.

    PubMed

    Onyekwelu, Obi; Kosutic, Damir

    2016-01-01

    Wide local excision of skin cancer in the lumbar area is a challenge to reconstruct. We report on the successful use of a two perforators-based superior gluteal artery perforator propeller flap, for the reconstruction of a lumbar defect.

  11. Uranus rings and two moons

    NASA Technical Reports Server (NTRS)

    1986-01-01

    Voyager 2 has discovered two 'shepherd' satellites associated with the rings of Uranus. The two moons -- designated 1986U7 and 1986U8 -- are seen here on either side of the bright epsilon ring; all nine of the known Uranian rings are visible. The image was taken Jan. 21, 1986, at a distance of 4.1 million kilometers (2.5 million miles) and resolution of about 36 km (22 mi). The image was processed to enhance narrow features. The epsilon ring appears surrounded by a dark halo as a result of this processing; occasional blips seen on the ring are also artifacts. Lying inward from the epsilon ring are the delta, gamma and eta rings; then the beta and alpha rings; and finally the barely visible 4, 5 and 6 rings. The rings have been studied since their discovery in 1977, through observations of how they diminish the light of stars they pass in front of. This image is the first direct observation of all nine rings in reflected sunlight. They range in width from about 100 km (60 mi) at the widest part of the epsilon ring to only a few kilometers for most of the others. The discovery of the two ring moons 1986U7 and 1986U8 is a major advance in our understanding of the structure of the Uranian rings and is in good agreement with theoretical predictions of how these narrow rings are kept from spreading out. Based on likely surface brightness properties, the moons are of roughly 2O- and 3O-km diameter, respectively. The Voyager project is managed for NASA by the Jet Propulsion Laboratory.

  12. Ideals of generalized matrix rings

    SciTech Connect

    Budanov, Aleksandr V

    2011-01-31

    Let R and S be rings, and {sub R}M{sub S} and {sub S}N{sub R} bimodules. In the paper, in terms of isomorphisms of lattices, relationships between the lattices of one-sided and two-sided ideals of the generalized matrix ring and the corresponding lattices of ideals of the rings R and S are described. Necessary and sufficient conditions for a pair of ideals I, J of rings R and S, respectively, to be the main diagonal of some ideal of the ring K are also obtained. Bibliography: 8 titles.

  13. O-Ring-Testing Fixture

    NASA Technical Reports Server (NTRS)

    Turner, James E.; Mccluney, D. Scott

    1991-01-01

    Fixture tests O-rings for sealing ability under dynamic conditions after extended periods of compression. Hydraulic cylinder moves plug in housing. Taper of 15 degrees on plug and cavity of housing ensures that gap created between O-ring under test and wall of cavity. Secondary O-rings above and below test ring maintain pressure applied to test ring. Evaluates effects of variety of parameters, including temperature, pressure, rate of pressurization, rate and magnitude of radial gap movement, and pretest compression time.

  14. New instability of Saturn's ring

    SciTech Connect

    Goertz, C.K.; Morfill, G.

    1988-05-01

    Perturbations in the Saturn ring's mass density are noted to be prone to instabilities through the sporadic elevation of submicron-size dust particles above the rings, which furnishes an effective angular momentum exchange between the rings and Saturn. The dust thus elevated from the ring settles back onto it at a different radial distance. The range of wavelength instability is determinable in light of the dust charge, the average radial displacement of the dust, and the fluctuation of these quantities. It is suggested that at least some of the B-ring's ringlets may arise from the instability.

  15. Helmet latching and attaching ring

    NASA Technical Reports Server (NTRS)

    Chase, E. W.; Viikinsalo, S. J. (Inventor)

    1970-01-01

    A neck ring releasably secured to a pressurized garment carries an open-ended ring normally in the engagement position fitted into an annular groove and adapted to fit into a complementary annular groove formed in a helmet. Camming means formed on the inner surface at the end of the helmet engages the open-ended ring to retract the same and allow for one motion donning even when the garment is pressurized. A projection on the end of the split ring is engageable to physically retract the split ring.

  16. Stress in Lumbar Intervertebral Discs during Distraction

    PubMed Central

    Gay, Ralph E.; Ilharreborde, Brice; Zhao, Kristin D.; Berglund, Lawrence J.; Bronfort, Gert; An, Kai-Nan

    2008-01-01

    BACKGROUND CONTEXT The intervertebral disc is a common source of low back pain. Prospective studies suggest that treatments that intermittently distract the disc might be beneficial for chronic low back pain. Although the potential exists for distraction therapies to affect the disc biomechanically their effect on intradiscal stress is debated. PURPOSE To determine if distraction alone, distraction combined with flexion or distraction combined with extension can reduce nucleus pulposus pressure and posterior anulus compressive stress in cadaveric lumbar discs compared to simulated standing or lying. STUDY DESIGN Laboratory study using single cadaveric motion segments. OUTCOME MEASURES Strain gauge measures of nucleus pulposus pressure and compressive stress in the anterior and posterior annulus fibrosus METHODS Intradiscal stress profilometry was performed on 15 motion segments during 5 simulated conditions: standing, lying, and 3 distracted conditions. Disc degeneration was graded by inspection from 1 (normal) to 4 (severe degeneration). RESULTS All distraction conditions markedly reduced nucleus pressure compared to either simulated standing or lying. There was no difference between distraction with flexion and distraction with extension in regard to posterior annulus compressive stress. Discs with little or no degeneration appeared to distributed compressive stress differently than those with moderate or severe degeneration. CONCLUSIONS Distraction appears to predictably reduce nucleus pulposus pressure. The effect of distraction therapy on the distribution of compressive stress may be dependent in part on the health of the disc. PMID:17981092

  17. Risk Factors for Recurrent Lumbar Disc Herniation

    PubMed Central

    Huang, Weimin; Han, Zhiwei; Liu, Jiang; Yu, Lili; Yu, Xiuchun

    2016-01-01

    Abstract Recurrent lumbar disc herniation (rLDH) is a common complication following primary discectomy. This systematic review aimed to investigate the current evidence on risk factors for rLDH. Cohort or case-control studies addressing risk factors for rLDH were identified by search in Pubmed (Medline), Embase, Web of Science, and Cochrane library from inception to June 2015. Relevant results were pooled to give overall estimates if possible. Heterogeneity among studies was examined and publication bias was also assessed. A total of 17 studies were included in this systematic review. Risk factors that had significant relation with rLDH were smoking (OR 1.99, 95% CI 1.53–2.58), disc protrusion (OR 1.79, 95% CI 1.15–2.79), and diabetes (OR 1.19, 95% CI 1.06–1.32). Gender, BMI, occupational work, level, and side of herniation did not correlate with rLDH significantly. Based on current evidence, smoking, disc protrusion, and diabetes were predictors for rLDH. Patients with these risk factors should be paid more attention for prevention of recurrence after primary surgery. More evidence provided by high-quality observational studies is still needed to further investigate risk factors for rLDH. PMID:26765413

  18. Lubrication regimes in lumbar total disc arthroplasty.

    PubMed

    Shaheen, A; Shepherd, D E T

    2007-08-01

    A number of total disc arthroplasty devices have been developed. Some concern has been expressed that wear may be a potential failure mode for these devices, as has been seen with hip arthroplasty. The aim of this paper was to investigate the lubrication regimes that occur in lumbar total disc arthroplasty devices. The disc arthroplasty was modelled as a ball-and-socket joint. Elastohydrodynamic lubrication theory was used to calculate the minimum film thickness of the fluid between the bearing surfaces. The lubrication regime was then determined for different material combinations, size of implant, and trunk velocity. Disc arthroplasties with a metal-polymer or metal-metal material combination operate with a boundary lubrication regime. A ceramic-ceramic material combination has the potential to operate with fluid-film lubrication. Disc arthroplasties with a metal-polymer or metal-metal material combination are likely to generate wear debris. In future, it is worth considering a ceramic-ceramic material combination as this is likely to reduce wear.

  19. Case report of lumbar intradural capillary hemangioma

    PubMed Central

    Unnithan, Ajaya Kumar Ayyappan; Joseph, T. P.; Gautam, Amol; Shymole, V.

    2016-01-01

    Background: Capillary hemangioma is a rare tumor in spinal intradural location. Despite the rarity, early recognition is important because of the risk of hemorrhage. This is a case report of a woman who had capillary hemangioma of cauda equina. Case Description: A 54 -year-old woman presented with a low backache, radiating to the left leg for 2 months. She had left extensor hallucis weakness, sensory impairment in left L5 dermatome, and mild tenderness in lower lumbar spine. Magnetic resonance imaging (MRI) LS spine showed L4/5 intradural tumor, completely occluding canal in myelogram, enhancing with contrast, s/o benign nerve sheath tumor. L4 laminectomy was done. Reddish tumor was seen originating from a single root. It was removed preserving the root. Postoperatively, she was relieved of symptoms. MRI showed no residue. Histopathology showed lobular proliferation of capillary-sized blood vessels and elongated spindle cells. Immunohistochemistry showed CD34 positivity in endothelial cell lining of blood vessel and smooth muscle actin positivity in blood vessel muscle cells. HPR-capillary hemangioma. Conclusion: Although rare, capillary hemangioma should be in the differential diagnosis of intradural tumors. It closely mimics nerve sheath tumor. PMID:27069745

  20. Osteolytic lumbar discal cyst: case report.

    PubMed

    Marushima, Aiki; Uemura, Kazuya; Sato, Naoaki; Maruno, Toru; Matsumura, Akira

    2008-08-01

    A 25-year-old man presented with left lumboischialgia refractory to medical treatment. Neurological examination revealed L5 and S1 radiculopathy which rapidly worsened over a short period. Magnetic resonance imaging demonstrated disk bulging with a discal cyst at the L4-5 intervertebral space and disk herniation at the L5-S1 intervertebral space. Computed tomography showed osteolytic change of the L5 vertebral body adjacent to the cyst. Resection of the cyst and removal of the herniated disk were performed following fenestration of the L4-5 and L5-S1 interlaminar spaces. Bloody serous fluid followed by clear serous fluid was recognized during the aspiration and partial resection of the cyst at the L4-5 level. Histological examination demonstrated a cyst wall consisting of fibrous connective tissue without a single-layer lining of cells, and fibrin deposits. The patient's symptoms disappeared immediately after the operation. This osteolytic lumbar discal cyst possibly occurred subsequent to hemorrhage from the epidural venous plexus following intervertebral disk injury, hematoma encapsulation by connective fibrous tissue, and cyst wall formation in reaction to the disk injury and hemorrhage. The cyst may have enlarged due to the inflow of the serous fluid from the water-containing degenerated disk. PMID:18719328

  1. Heterotopic Ossification Causing Radiculopathy after Lumbar Total Disc Arthroplasty.

    PubMed

    Jackson, Keith L; Hire, Justin M; Jacobs, Jeremy M; Key, Charles C; DeVine, John G

    2015-06-01

    To date, no reports have presented radiculopathy secondary to heterotopic ossification following lumbar total disc arthroplasty. The authors present a previously unpublished complication of lumbar total disk arthroplasty (TDA) secondary to heterotopic ossification (HO) in the spinal canal, and they propose a modification to the McAfee classification of HO. The patient had undergone an L5/S1 lumbar TDA two years prior due to discogenic back pain. His preoperative back pain was significantly relieved, but he developed new, atraumatic onset radiculopathy. Radiographs and a computed tomography myelogram revealed an implant malposition posteriorly with heterotopic bone formation in the canal, causing an impingement of the traversing nerve root. Revision surgery was performed with implant extraction, L5/S1 anterior lumbar interbody fusion, supplemental posterior decompression, and pedicle screw fixation. The patient tolerated the procedure well, with complete resolution of the radicular leg pain. At a two-year follow up, the patient had a solid fusion without subsidence or recurrence of heterotopic bone. This case represents a novel pattern of heterotopic ossification, and it describes a previously unreported cause for implant failure in lumbar disc replacement surgery-reinforcing the importance of proper intraoperative component positioning. We propose a modification to the existing McAfee classification of HO after TDA with the addition of Class V and VI HO. PMID:26097664

  2. Heterotopic Ossification Causing Radiculopathy after Lumbar Total Disc Arthroplasty

    PubMed Central

    Jackson, Keith L.; Jacobs, Jeremy M.; Key, Charles C.; DeVine, John G.

    2015-01-01

    To date, no reports have presented radiculopathy secondary to heterotopic ossification following lumbar total disc arthroplasty. The authors present a previously unpublished complication of lumbar total disk arthroplasty (TDA) secondary to heterotopic ossification (HO) in the spinal canal, and they propose a modification to the McAfee classification of HO. The patient had undergone an L5/S1 lumbar TDA two years prior due to discogenic back pain. His preoperative back pain was significantly relieved, but he developed new, atraumatic onset radiculopathy. Radiographs and a computed tomography myelogram revealed an implant malposition posteriorly with heterotopic bone formation in the canal, causing an impingement of the traversing nerve root. Revision surgery was performed with implant extraction, L5/S1 anterior lumbar interbody fusion, supplemental posterior decompression, and pedicle screw fixation. The patient tolerated the procedure well, with complete resolution of the radicular leg pain. At a two-year follow up, the patient had a solid fusion without subsidence or recurrence of heterotopic bone. This case represents a novel pattern of heterotopic ossification, and it describes a previously unreported cause for implant failure in lumbar disc replacement surgery-reinforcing the importance of proper intraoperative component positioning. We propose a modification to the existing McAfee classification of HO after TDA with the addition of Class V and VI HO. PMID:26097664

  3. Lumbar Stenosis: A Recent Update by Review of Literature

    PubMed Central

    Lee, Seung Yeop; Kim, Tae-Hwan; Oh, Jae Keun; Lee, Seung Jin

    2015-01-01

    Degeneration of the intervertebral disc results in initial relative instability, hypermobility, and hypertrophy of the facet joints, particularly at the superior articular process. This finally leads to a reduction of the spinal canal dimensions and compression of the neural elements, which can result in neurogenic intermittent claudication caused by venous congestion and arterial hypertension around nerve roots. Most patients with symptomatic lumbar stenosis had neurogenic intermittent claudication with the risk of a fall. However, although the physical findings and clinical symptoms in lumbar stenosis are not acute, the radiographic findings are comparatively severe. Magnetic resonance imaging is a noninvasive and good method for evaluation of lumbar stenosis. Though there are very few studies pertaining to the natural progression of lumbar spinal stenosis, symptoms of spinal stenosis usually respond favorably to non-operative management. In patients who fail to respond to non-operative management, surgical treatments such as decompression or decompression with spinal fusion are required. Restoration of a normal pelvic tilt after lumbar fusion correlates to a good clinical outcome. PMID:26435805

  4. Effects of interspinous spacers on lumbar degenerative disease.

    PubMed

    Zhou, Dong; Nong, Lu-Ming; DU, Rui; Gao, Gong-Ming; Jiang, Yu-Qing; Xu, Nan-Wei

    2013-03-01

    The present study aimed to evaluate the early effects of interspinous spacers on lumbar degenerative disease. The clinical outcomes of 23 patients with lumbar degenerative disease, treated using interspinous spacer implantation alone or combined with posterior lumbar fusion, were retrospectively studied and assessed with a visual analogue scale (VAS) and the Oswestry Disability Index (ODI). Pre-operative and post-operative interspinous distance, disc space height, foraminal width and height and segmental lordosis were determined. The early effects and complications associated with the interspinous spacers were recorded. The surgical procedures performed with the in-space treatment were easy and minimally invasive. The VAS scores and ODI were improved post-operatively compared with pre-operatively. Significant changes in the interspinous distance, disc space height, foraminal width and height and segmental lordosis were noted. In-space treatment for degenerative lumbar disease is easy and safe, with good early effects. The in-space system provides an alternative treatment for lumbar degenerative disease.

  5. Jogging gait kinetics following fatiguing lumbar paraspinal exercise.

    PubMed

    Hart, Joseph M; Kerrigan, D Casey; Fritz, Julie M; Saliba, Ethan N; Gansneder, Bruce; Ingersoll, Christopher D

    2009-12-01

    A relationship exists between lumbar paraspinal muscle fatigue and quadriceps muscle activation. The objective of this study was to determine whether hip and knee joint moments during jogging changed following paraspinal fatiguing exercise. Fifty total subjects (25 with self-reported history of low back pain) performed fatiguing, isometric lumbar extension exercise until a shift in EMG median frequency corresponding to a mild level of muscle fatigue was observed. We compared 3-dimensional external joint moments of the hip and knee during jogging before and after lumbar paraspinal fatigue using a 10-camera motion analysis system. Reduced external knee flexion, knee adduction, knee internal rotation and hip external rotation moments and increased external knee extension moments resulted from repetitive lumbar paraspinal fatiguing exercise. Persons with a self-reported history of LBP had larger knee flexion moments than controls during jogging. Neuromuscular changes in the lower extremity occur while resisting knee and hip joint moments following isolated lumbar paraspinal exercise. Persons with a history of LBP seem to rely more heavily on quadriceps activity while jogging.

  6. [Isokinetic and functional lumbar evaluation in workers pensioned with disability].

    PubMed

    Navarro-Trujillo, Luz Rocío; Mireles-Pérez, Ana Bárbara Isabel; Castañeda-Borrayo, Yaocihuatl; Plascencia-García, José Luis

    2013-01-01

    Introducción: en 2008 se formularon 13 371 dictámenes de invalidez en Jalisco, gran parte de ellos motivados por lesiones de la columna lumbar. La mayoría es de naturaleza definitiva y requiere evaluaciones completas de las capacidades lumbares. El objetivo de esta investigación fue evaluar la funcionalidad de la columna lumbar con el cuestionario de Oswestry y con el estudio isocinético en pensionados por lesiones lumbares. Métodos: estudio comparativo de 20 trabajadores con dictamen de invalidez por lesiones lumbares, a quienes se les solicitó realizar ejercicios isocinéticos y contestar el cuestionario de Oswestry. Resultados: con el cuestionario de Oswestry se determinó una discapacidad de 60 %. En cuanto a la evaluación isocinética, en la extensión se obtuvo un torque máximo de 44 Nw. En el trabajo fatiga se encontraron una media y una moda de cero. En la flexión, el torque máximo fue de -75.5 Nw. En la potencia, la moda fue de 40 V. En el trabajo-fatiga, la media y la moda fueron de cero. Conclusiones: la evaluación isocinética no fue normal en ninguno de los trabajadores, con lo que se corroboró la invalidez.

  7. Embolization of Isolated Lumbar Artery Injuries in Trauma Patients

    SciTech Connect

    Sofocleous, Constantinos T. Hinrichs, Clay R.; Hubbi, Basil; Doddakashi, Satish; Bahramipour, Philip; Schubert, Johanna

    2005-12-15

    Purpose. The purpose of the study was to evaluate the angiographic findings and results of embolotherapy in the management of lumbar artery trauma. Methods. All patients with lumbar artery injury who underwent angiography and percutaneous embolization in a state trauma center within a 10-year period were retrospectively reviewed. Radiological information and procedural reports were reviewed to assess immediate angiographic findings and embolization results. Long-term clinical outcome was obtained by communication with the trauma physicians as well as with chart review. Results. In a 10-year period, 255 trauma patients underwent abdominal aortography. Eleven of these patients (three women and eight men) suffered a lumbar artery injury. Angiography demonstrated active extravasation (in nine) and/or pseudoaneurysm (in four). Successful selective embolization of abnormal vessel(s) was performed in all patients. Coils were used in six patients, particles in one and gelfoam in five patients. Complications included one retroperitoneal abscess, which was treated successfully. One patient returned for embolization of an adjacent lumbar artery due to late pseudoaneurysm formation. Conclusions. In hemodynamically stable patients, selective embolization is a safe and effective method for immediate control of active extravasation, as well as to prevent future hemorrhage from an injured lumbar artery.

  8. A season in Saturn's rings: Cycling, recycling and ring history

    NASA Astrophysics Data System (ADS)

    Esposito, L. W.; Meinke, B. K.; Albers, N.; Sremcevic, M.

    2012-04-01

    Cassini experiments have watched Saturn's ring system evolve before our eyes. Images and occultations show changes and transient events. The rings are a dynamic and complex geophysical system, incompletely modeled as a single-phase fluid. Key Cassini observations: High resolution images show straw, propellers, embedded moonlets, and F ring objects. Multiple UVIS, RSS and VIMS occutlations indicate multimodal ringlet and edge structure, including free and forced modes along with stochastic perturbations that are most likely caused by nearby mass concentrations. Vertical excursions are evident at ring edges and in other perturbed regions. The rings are occasionally hit by meteorites that leave a signature that may last centuries; meteoritic dust pollutes the rings. Temperature, reflectance and transmission spectra are influenced by the dynamical state of the ring particles. Saturn's Equinox 2009: Oblique lighting exposed vertical structure and embedded objects. The rings were the coldest ever. Images inspired new occultation and spectral analysis that show abundant structure in the perturbed regions. The rings are more variable and complex than we had expected prior to this seasonal viewing geometry. Sub-kilometer structure in power spectral analysis: Wavelet analysis shows features in the strongest density waves and at the shepherded outer edge of the B ring. Edges are variable as shown by multiple occultations and occultations of double stars. F ring kittens: 25 features seen in the first 102 occultations show a weak correlation with Prometheus location. We interpret these features as temporary aggregations. Simulation results indicate that accretion must be enhanced to match the kittens' size distribution. Images show that Prometheus triggers the formation of transient objects. Propellers and ghosts: Occulations and images provide evidence for small moonlets in the A, B and C rings. These indicate accretion occurs inside the classical Roche limit. Implications

  9. Multiexpandable cage for minimally invasive posterior lumbar interbody fusion

    PubMed Central

    Coe, Jeffrey D; Zucherman, James F; Kucharzyk, Donald W; Poelstra, Kornelis A; Miller, Larry E; Kunwar, Sandeep

    2016-01-01

    The increasing adoption of minimally invasive techniques for spine surgery in recent years has led to significant advancements in instrumentation for lumbar interbody fusion. Percutaneous pedicle screw fixation is now a mature technology, but the role of expandable cages is still evolving. The capability to deliver a multiexpandable interbody cage with a large footprint through a narrow surgical cannula represents a significant advancement in spinal surgery technology. The purpose of this report is to describe a multiexpandable lumbar interbody fusion cage, including implant characteristics, intended use, surgical technique, preclinical testing, and early clinical experience. Results to date suggest that the multiexpandable cage allows a less invasive approach to posterior/transforaminal lumbar interbody fusion surgery by minimizing iatrogenic risks associated with static or vertically expanding interbody prostheses while providing immediate vertebral height restoration, restoration of anatomic alignment, and excellent early-term clinical results. PMID:27729817

  10. [Endovascular repair of iliocaval arteriovenous fistula complicating lumbar disc surgery].

    PubMed

    Ben Jemaa, H; Maalej, A; Lazzez, K; Jemal, H; Karray, S; Ben Mahfoudh, K

    2016-05-01

    Vascular complications of lumbar disc surgery are rare. Few cases have been reported. Arteriovenous fistulas are the most common. They are due to anatomical relationships between the last lumbar vertebrae, the corresponding discs, and the iliac vessels; degenerative lesions of the intervertebral discs facilitate instrumental vessel perforation, and operative difficulty. Computed tomography is particularly accurate for making the diagnosis. Treatment strategies consist in surgery or endovascular management. Percutaneous endovascular treatment using a stent-graft is a reasonable option for treating arteriovenous fistula. We describe the case of a 50-year-old patient who developed an iliocaval arteriovenous fistula following lumbar disc hernia surgery. The lesion was excluded by a stent-graft. The postoperative period was uneventful. PMID:26920402

  11. Low back pain and lumbar angles in Turkish coal miners

    SciTech Connect

    Sarikaya, S.; Ozdolap, S.; Gumustas, S.; Koc, U.

    2007-02-15

    This study was designed to assess the incidence of low back pain among Turkish coal miners and to investigate the relationship between angles of the lumbar spine and low back pain in coal miners. Fifty underground workers (Group I) and 38 age-matched surface workers (Group II) were included in the study. All the subjects were asked about low back pain in the past 5 years. The prevalence of low back pain was higher in Group I than in Group II (78.0%, 32.4%, respectively, P {lt} 0.001). The results of the study showed that low back pain occurred in 78.0% of Turkish coal miners. Although the nature of the occupation may have influenced coal miners' lumbar spinal curvature, lumbar angles are not a determinant for low back pain in this population. Further extensive studies involving ergonomic measurements are needed to validate our results for Turkish coal mining industry.

  12. Conservative management of psoas haematoma following complex lumbar surgery

    PubMed Central

    Lakkol, Sandesh; Sarda, Praveen; Karpe, Prasad; Krishna, Manoj

    2014-01-01

    We report psoas hematoma communicating with extradural hematoma and compressing on lumbar nerve roots during the postoperative period in a patient who underwent L3/4 level dynamic stabilization and L4/5 and L5/S1 posterior lumbar interbody fusion. Persistent radicular symptoms occurring soon after posterior lumbar surgery are not an unknown entity. However, psoas hematoma communicating with the extradural hematoma and compressing on L4 and L5 nerve roots soon after surgery, leading to radicular symptoms has not been reported. In addition to the conservative approach in managing such cases, this case report also emphasizes the importance of clinical evaluation and utilization of necessary imaging techniques such as computed tomography (CT) scan and magnetic resonance imaging (MRI) scan to diagnose the cause of persistent severe radicular pain in the postoperative period. PMID:24600073

  13. [Incidence of extra-arachnoid discharge following lumbar puncture].

    PubMed

    Wiggli, U; Oberson, R

    1975-02-22

    Dimer-X is considered a good contrast medium for lumbar myelography. Its physical properties guarantee a homogeneous mixture with cerebrospinal fluid, with the result that postpunctural fluid leakage is easy to detect. One hundred Dimer-X lumbar myelographies were performed with two different spinal needles, a short beveled needle of 1.2 mm outer diameter and a special beveled "Quincke" needle of 0.7 mm outer diameter. Postpunctural fluid leakage is observed in 32% of the cases with the former and in only 12% with the latter. False-route injections occurred in 5% of the cases. Epidural leakage is the most frequent and can be detected by its "Christmas tree" appearance on antero-posterior X-ray. Subdural leakage is represented by a "railroad track" appearance on a lateral view. The leakage is observed more frequently in patients with normal myelogram (28%) than in patients with a herniated lumbar disc (18%).

  14. A rare cause of lumbar radiculopathy: spinal gas collection.

    PubMed

    Tamburrelli, F; Leone, A; Pitta, L

    2000-10-01

    The presence of gas in the intervertebral disk space, known as the vacuum phenomenon, is a relatively common radiologic finding, especially on computed tomographic investigation. In a few cases, the gas can be collected into the lumbar spinal canal and can also compress the nerve root. To date only seven cases of symptomatic lumbar radiculopathy caused by a bubble of gas are reported in the literature. The presence of gas inside a narrowed disk and the collection of gas in the spinal canal suggest a communication between the two structures. A case of lumbar radiculopathy caused by a collection of gas in the spinal canal provided the authors the opportunity to study this rare condition by magnetic resonance imaging. Magnetic resonance imaging had not been used before in the referred cases and proved conclusively the discal origin of the gas. PMID:11052357

  15. Continuous ring furnaces

    SciTech Connect

    De Stefani, G.; Genevois, J.L.; Paolo, P.

    1981-01-06

    A smoke conducting apparatus for use particularly with continuous ring furnaces (e.g., Hoffman furnaces) wherein each furnace chamber is connected to the smoke channel, the latter being a metal pipe inclined slightly from horizontal and provided with one or more traps along the length of its bottom surface, each trap containing a removable receptacle, and heating means being disposed along the bottom of the channel to fluidize tarry deposits of combustion products so that such deposits will flow by gravity into the removable receptacle.

  16. The role of cumulative physical work load in lumbar spine disease: risk factors for lumbar osteochondrosis and spondylosis associated with chronic complaints

    PubMed Central

    Seidler, A; Bolm-Audorff, U; Heiskel, H; Henkel, N; Roth-Kuver, B; Kaiser, U; Bickeboller, R; Willingstorfer, W; Beck, W; Elsner, G

    2001-01-01

    OBJECTIVES—To investigate the relation with a case-control study between symptomatic osteochondrosis or spondylosis of the lumbar spine and cumulative occupational exposure to lifting or carrying and to working postures with extreme forward bending.
METHODS—From two practices and four clinics were recruited 229 male patients with radiographically confirmed osteochondrosis or spondylosis of the lumbar spine associated with chronic complaints. Of these 135 had additionally had acute lumbar disc herniation. A total of 197 control subjects was recruited: 107 subjects with anamnestic exclusion of lumbar spine disease were drawn as a random population control group and 90 patients admitted to hospital for urolithiasis who had no osteochondrosis or spondylosis of the lumbar spine radiographically were recruited as a hospital based control group. Data were gathered in a structured personal interview and analysed using logistic regression to control for age, region, nationality, and other diseases affecting the lumbar spine. To calculate cumulative forces to the lumbar spine over the entire working life, the Mainz-Dortmund dose model (MDD), which is based on an overproportional weighting of the lumbar disc compression force relative to the respective duration of the lifting process was applied with modifications: any objects weighing ⩾5 kg were included in the calculation and no minimum daily exposure limits were established. Calculation of forces to the lumbar spine was based on self reported estimates of occupational lifting, trunk flexion, and duration.
RESULTS—For a lumbar spine dose >9×106 Nh (Newton×hours), the risk of having radiographically confirmed osteochondrosis or spondylosis of the lumbar spine as measured by the odds ratio (OR) was 8.5 (95% confidence interval (95% CI) 4.1 to 17.5) compared with subjects with a load of 0 Nh. To avoid differential bias, forces to the lumbar spine were also calculated on the basis of an internal job

  17. Genetic Association Studies in Lumbar Disc Degeneration: A Systematic Review

    PubMed Central

    Eskola, Pasi J.; Lemmelä, Susanna; Kjaer, Per; Solovieva, Svetlana; Männikkö, Minna; Tommerup, Niels; Lind-Thomsen, Allan; Husgafvel-Pursiainen, Kirsti; Cheung, Kenneth M. C.; Chan, Danny

    2012-01-01

    Objective Low back pain is associated with lumbar disc degeneration, which is mainly due to genetic predisposition. The objective of this study was to perform a systematic review to evaluate genetic association studies in lumbar disc degeneration as defined on magnetic resonance imaging (MRI) in humans. Methods A systematic literature search was conducted in MEDLINE, MEDLINE In-Process, SCOPUS, ISI Web of Science, The Genetic Association Database and The Human Genome Epidemiology Network for information published between 1990–2011 addressing genes and lumbar disc degeneration. Two investigators independently identified studies to determine inclusion, after which they performed data extraction and analysis. The level of cumulative genetic association evidence was analyzed according to The HuGENet Working Group guidelines. Results Fifty-two studies were included for review. Forty-eight studies reported at least one positive association between a genetic marker and lumbar disc degeneration. The phenotype definition of lumbar disc degeneration was highly variable between the studies and replications were inconsistent. Most of the associations presented with a weak level of evidence. The level of evidence was moderate for ASPN (D-repeat), COL11A1 (rs1676486), GDF5 (rs143383), SKT (rs16924573), THBS2 (rs9406328) and MMP9 (rs17576). Conclusions Based on this first extensive systematic review on the topic, the credibility of reported genetic associations is mostly weak. Clear definition of lumbar disc degeneration phenotypes and large population-based cohorts are needed. An international consortium is needed to standardize genetic association studies in relation to disc degeneration. PMID:23185509

  18. Saturn ring temperature variations with approaching ring equinox

    NASA Astrophysics Data System (ADS)

    Spilker, L.; Leyrat, C.; Flandes, A.; Altobelli, N.; Pilorz, S.; Ferrari, C.; Edgington, S.

    2009-04-01

    Cassini's Composite Infrared Spectrometer (CIRS) has acquired a wide-ranging set of thermal measurements of Saturn's main rings (A, B, C and Cassini Division) at solar elevations ranging from less than one degree to 24 degrees. At Saturn equinox in August the solar elevation angle will reach zero as the sun traverses from the south to north side of the rings. For the data acquired to date, temperatures were retrieved for the lit and unlit rings over a variety of ring geometries that include solar elevation, as well as spacecraft elevation, phase angle and local hour angle. To first order, the largest temperature changes on the lit face of the rings are driven by variations in phase angle while differences in temperature with changing spacecraft elevation and local time are a secondary effect. Decreasing ring temperature with decreasing solar elevation are observed for both the lit and unlit faces of the rings after phase angle and local time effects are taken into account. As the solar elevation continues to decrease, the ring temperatures are decreasing in a non-linear fashion. The difference in temperature between the lit and unlit sides of the rings is decreasing also with decreasing solar elevation. Using ring thermal models developed by Leyrat we extrapolate to the expected minimum ring temperatures at equinox for our planned CIRS ring observations. This research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA and at CEA Saclay supported by the "Programme National de Planetologie". Copyright 2009 California Institute of Technology. Government sponsorship acknowledged.

  19. Foot side detection from lower lumbar spine acceleration.

    PubMed

    Ben Mansour, Khaireddine; Rezzoug, Nasser; Gorce, Philippe

    2015-09-01

    The purpose of this paper is to present a reliable algorithm to discriminate between left/right foot contact using an accelerometer located over the lower lumbar spine. With the given accelerometer frame orientation, the side detection algorithm, based on the sign of the derivative of the sinusoidal shape obtained from the filtered mediolateral (ML) acceleration, showed 100% correct side detection for all subjects at all walking velocities. From the obtained results, it is concluded that in healthy subjects, the side of subsequent foot contact can be reliably obtained from the ML acceleration pattern of the lower lumbar spine.

  20. [Lumbar spine injuries in pediatric and adolescent athletes].

    PubMed

    Berk, R Haluk

    2004-01-01

    During the past two decades, there has been a significant increase in sports participation by pediatric athletes. Spinal injuries thus have become a great concern. The unique nature of the pediatric spine should be well-recognized and low back pain in a pediatric athlete should therefore be taken seriously and evaluated thoroughly. In this review article, sports-related lumbar spine problems will be covered including overuse injuries, spondylolysis, pars stress fractures, spondylolysthesis, and lumbar disc herniation. Early identification of these problems will eventually minimize these injuries. PMID:15187460

  1. Laparoscopic management of inferior lumbar hernia (Petit triangle hernia).

    PubMed

    Ipek, T; Eyuboglu, E; Aydingoz, O

    2005-05-01

    Lumbar hernias are rare defects in the posterolateral abdominal wall that may be congenital or acquired. We present a case of laparoscopic approach to repair an acquired inferior triangle (Petit) lumbar hernia in a woman by using polytetrafluoroethylene mesh. The size of the hernia was 8 x 10 cm. The length of her hospital stay was 2 days. The patient resumed normal activities in less than 2 weeks. The main advantage of this approach is excellent operative visualization, thus avoiding injury to structures near the hernia during repair. Patients benefit from a minimally invasive approach with less pain, shortened hospital course, less analgesic requirements, better cosmetic result, and minimal life-style interference.

  2. Incarcerated small bowel within a spontaneous lumbar hernia.

    PubMed

    Teo, K A T; Burns, E; Garcea, G; Abela, J E; McKay, C J

    2010-10-01

    Lumbar hernias are rare, resulting from protrusion through the posterior abdominal wall that may be congenital, acquired or spontaneous. They very rarely present with acute bowel obstruction. We present a case of incarcerated small bowel within a spontaneous inferior (Petit's) lumbar hernia, treated by early open repair with mesh insertion. This case highlights the importance of thorough clinical examination and a high index of suspicion, even in the absence of previous surgery around the anatomical site of the suspected hernia, in order to effect an early repair before the onset of ischaemia in incarcerated contents.

  3. Destructive discovertebral degenerative disease of the lumbar spine.

    PubMed

    Charran, A K; Tony, G; Lalam, R; Tyrrell, P N M; Tins, B; Singh, J; Eisenstein, S M; Balain, B; Trivedi, J M; Cassar-Pullicino, V N

    2012-09-01

    The uncommon variant of degenerative hip joint disease, termed rapidly progressive osteoarthritis, and highlighted by severe joint space loss and osteochondral disintegration, is well established. We present a similar unusual subset in the lumbar spine termed destructive discovertebral degenerative disease (DDDD) with radiological features of vertebral malalignment, severe disc resorption, and "bone sand" formation secondary to vertebral fragmentation. Co-existing metabolic bone disease is likely to promote the development of DDDD of the lumbar spine, which presents with back pain and sciatica due to nerve root compression by the "bone sand" in the epidural space. MRI and CT play a complimentary role in making the diagnosis.

  4. Retroperitoneal approach for lumbar lateral meningocele--case report.

    PubMed

    Miyata, M; Yamasaki, S; Yoshida, T; Matsubara, M; Okamura, M; Hirayama, A; Tamaki, N

    1995-12-01

    A 29-year-old female with neurofibromatosis presented with a right lumbar lateral meningocele. Abdominal computed tomography (CT) showed a huge right retroperitoneal cyst expanding anterolaterally and displacing the right kidney. CT following myelography disclosed the cyst expanding through a wide defect of the right pedicles of the T-12 and L-1 vertebrae. The cyst was resected through a retroperitoneal approach with right flank oblique incision. Postoperatively, cerebrospinal fluid leakage occurred, which improved after lumboperitoneal shunt. Careful screening for lateral meningocele, including the lumbar region, should be undertaken in a patient with neurofibromatosis who presents with vertebral anomalies.

  5. Thoracic and lumbar extradural structure examined by extraduroscope.

    PubMed

    Igarashi, T; Hirabayashi, Y; Shimizu, R; Saitoh, K; Fukuda, H

    1998-08-01

    We examined the extradural space using a flexible extraduroscope in 113 patients undergoing extradural anaesthesia. Patients were classified into two groups to receive either thoracic or lumbar extradural anaesthesia as needed for perioperative analgesia. The extraduroscopy showed that the thoracic extradural space becomes widely patent after injecting a given amount of air and that the amount of fatty and fibrous connective tissue is less in the thoracic extradural space compared with the lumbar extradural space. We suggest that differences between the structure of these two vertebral regions may affect the spread of local anaesthetics in the extradural space. PMID:9813508

  6. Range of Motion of the Intact Lumbar Segment: A Multivariate Study of 42 Lumbar Spines

    PubMed Central

    Cook, Daniel J.; Yeager, Matthew S.

    2015-01-01

    Background A thorough understanding of the biomechanical characteristics of the healthy human spine is critical in furthering the treatment of spinal pathology. The goal of this study was to investigate the motion of the intact lumbar spine segment as measured by range of motion (ROM), and to investigate the dependencies thereof on gender and intervertebral level. Materials and Methods Kinematic data was obtained for 42 human lumbar segments (L1-S1) in response to a pure-moment loading protocol in flexion extension (FE), lateral bending (LB) and axial torsion (AT). Data was obtained for 204 individual functional spinal units (91 female, 113 male). Multivariate analysis of variance was conducted to detect differences between genders and intervertebral levels in each mode of loading. Correlations between ROM and donor demographics, including height, weight, and age, were conducted. Results ROM was significantly greater for females than for males in FE, LB and AT (p<0.001). ROM tended to increase down the vertebral column in FE. L3-4 FE ROM was significantly greater than L1-2 (p=0.024), and L4-5 and L5-S1 FE ROM were significantly greater than for every other level (p<0.003). LB ROM tended to be greater toward the center of the segment with L2-3, L3-4 and L4-5 ROM being significantly greater than both L1-2 (p<0.001) and L5-S1 (p=0.006, p<0.001, p=0.043, respectively). A similar trend was found for AT, however only L1-2 was significantly less than all other levels (p=0.042, p<0.001, p<0.001, and p=0.034 for L2-3, L3-4, L4-5, and L5-S1 respectively). Conclusion The significant differences in lumbar ROM between male and female spine segments and between the intervertebral levels must be taken into account in study design in order to prevent biases in outcomes. The significant differences in ROM between levels may also have critical implications in the design of spinal implants, particularly those designed to maintain or restore healthy motion. PMID:25785241

  7. Transforaminal lumbar interbody fusion versus posterolateral fusion in degenerative lumbar spondylosis

    PubMed Central

    Zhang, Bin-Fei; Ge, Chao-Yuan; Zheng, Bo-Long; Hao, Ding-Jun

    2016-01-01

    Abstract Objective: The aim of the study was to evaluate the efficacy and safety of transforaminal lumbar interbody fusion (TLIF) versus posterolateral fusion (PLF) in degenerative lumbar spondylosis. Methods: A systematic literature review was performed to obtain randomized controlled trials (RCTs) and observational studies (OSs) of TLIF and PLF for degenerative lumbar spondylosis. Trials performed before November 2015 were retrieved from the Medline, EMBASE, Cochrane library, and Chinese databases. Data extraction and quality evaluation of the trials were performed independently by 2 investigators. A meta-analysis was performed using STATA version 12.0. Results: Two RCTs and 5 OSs of 630 patients were included. Of these subjects, 325 were in the TLIF and 305 were in the PLF group. Results showed that TLIF did not increase the fusion rate based on RCTs (relative risk [RR] = 1.06; 95% confidence interval [CI]: 0.95–1.18; P = 0.321), but increased it based on OSs (RR = 1.14; 95% CI: 1.07–1.23; P = 0.000) and overall (RR = 1.11; 95% CI: 1.05–1.18; P = 0.001) as compared with PLF. TLIF was able to improve the clinical outcomes based on 1 RCT (RR = 1.33; 95% CI: 1.11–1.59, P = 0.002) and overall (RR = 1.19; 95% CI: 1.07–1.33; P = 0.001), but not based on OSs (RR = 1.11; 95% CI: 0.97–1.27; P = 0.129) as compared with PLF. There were no differences between TLIF and PLF in terms of visual analogue scale, Oswestry Disability Index, reoperation, complications, duration of surgical procedure, blood loss, and hospitalization. Conclusions: In conclusion, evidence is not sufficient to support that TLIF provides higher fusion rate than PLF, and this poor evidence indicates that TLIF might improve only clinical outcomes. Higher quality, multicenter RCTs are needed to better define the role of TLIF and PLF. PMID:27749558

  8. Ring Image Analyzer

    NASA Technical Reports Server (NTRS)

    Strekalov, Dmitry V.

    2012-01-01

    Ring Image Analyzer software analyzes images to recognize elliptical patterns. It determines the ellipse parameters (axes ratio, centroid coordinate, tilt angle). The program attempts to recognize elliptical fringes (e.g., Newton Rings) on a photograph and determine their centroid position, the short-to-long-axis ratio, and the angle of rotation of the long axis relative to the horizontal direction on the photograph. These capabilities are important in interferometric imaging and control of surfaces. In particular, this program has been developed and applied for determining the rim shape of precision-machined optical whispering gallery mode resonators. The program relies on a unique image recognition algorithm aimed at recognizing elliptical shapes, but can be easily adapted to other geometric shapes. It is robust against non-elliptical details of the image and against noise. Interferometric analysis of precision-machined surfaces remains an important technological instrument in hardware development and quality analysis. This software automates and increases the accuracy of this technique. The software has been developed for the needs of an R&TD-funded project and has become an important asset for the future research proposal to NASA as well as other agencies.

  9. Lumbar corpectomy for correction of degenerative scoliosis from osteoradionecrosis reveals a delayed complication of lumbar myxopapillary ependymoma.

    PubMed

    Palejwala, Sheri K; Lawson, Kevin A; Kent, Sean L; Martirosyan, Nikolay L; Dumont, Travis M

    2016-08-01

    Osteoradionecrosis is a known complication following radiation therapy, presenting most commonly in the cervical spine as a delayed consequence of radiation that is often necessary in the management of head and neck cancers. In contrast, osteoradionecrosis has rarely been described in the lumbar spine. Here we describe, to our knowledge, the first reported case of lumbar spine osteoradionecrosis, after adjuvant radiation for a primary spinal cord tumor, leading to progressive degenerative scoliosis which required subsequent operative management. Established guidelines recommend that mature bone can tolerate a dose of up to 6000 cGy without injury. However, once bone has been exposed to radiation over this level progressive soft tissue changes may lead to devascularization, leaving the bone vulnerable to osteonecrosis, specifically when manipulated. Radiation necrosis can be progressive and lead to eventual mechanical instability requiring debridement and surgical fixation. In the setting of the lumbar spine, osseous necrosis can lead to biomechanical instability, deformity, pain, and neurologic deficit. PMID:27056674

  10. The Use of Lumbar Spine Magnetic Resonance Imaging in Eastern China: Appropriateness and Related Factors.

    PubMed

    Yu, Liedao; Wang, Xuanwei; Lin, Xiangjin; Wang, Yue

    2016-01-01

    Back pain is common and costly. While a general scene of back pain related practice in China remains unknown, there are signs of excessive use of lumbar spine magnetic resonance (MR). We retrospectively studied 3107 lumbar spine MRIs in Eastern China to investigate the appropriateness of lumbar spine MR use. Simple back pain is the most common chief complaint for ordering a lumbar MR study. Only 41.3% of lumbar spine MR studies identified some findings that may have potential clinical significance. Normal lumbar spine is the most common diagnosis (32.7%), followed by lumbar disc bulging and lumbar disc herniation. Walk difficulties, back injury and referred leg pain as chief complaints were associated with greater chance of detecting potentially clinically positive lumbar MR image findings, as compare with simple back pain. There was no difference in positive rates among orthopedic surgeon and specialists of other disciplines. Lumbar spine MR imaging was generally overused in Eastern China by various specialists, particularly at health assessment centers. For appropriate use of lumbar spine MR, orthopedic surgeons are no better than physicians of other disciplines. Professional training and clinical guidelines are needed to facilitate evidence-based back pain practice in China. PMID:26731106

  11. The Use of Lumbar Spine Magnetic Resonance Imaging in Eastern China: Appropriateness and Related Factors

    PubMed Central

    Yu, Liedao; Wang, Xuanwei; Lin, Xiangjin; Wang, Yue

    2016-01-01

    Back pain is common and costly. While a general scene of back pain related practice in China remains unknown, there are signs of excessive use of lumbar spine magnetic resonance (MR). We retrospectively studied 3107 lumbar spine MRIs in Eastern China to investigate the appropriateness of lumbar spine MR use. Simple back pain is the most common chief complaint for ordering a lumbar MR study. Only 41.3% of lumbar spine MR studies identified some findings that may have potential clinical significance. Normal lumbar spine is the most common diagnosis (32.7%), followed by lumbar disc bulging and lumbar disc herniation. Walk difficulties, back injury and referred leg pain as chief complaints were associated with greater chance of detecting potentially clinically positive lumbar MR image findings, as compare with simple back pain. There was no difference in positive rates among orthopedic surgeon and specialists of other disciplines. Lumbar spine MR imaging was generally overused in Eastern China by various specialists, particularly at health assessment centers. For appropriate use of lumbar spine MR, orthopedic surgeons are no better than physicians of other disciplines. Professional training and clinical guidelines are needed to facilitate evidence-based back pain practice in China. PMID:26731106

  12. Intervertebral Fusion with Mobile Microendoscopic Discectomy for Lumbar Degenerative Disc Disease.

    PubMed

    Xu, Bao-Shan; Liu, Yue; Xu, Hai-Wei; Yang, Qiang; Ma, Xin-Long; Hu, Yong-Cheng

    2016-05-01

    The aim of this article is to introduce a technique for lumbar intervertebral fusion that incorporates mobile microendoscopic discectomy (MMED) for lumbar degenerative disc disease. Minimally invasive transforaminal lumbar interbody fusion is frequently performed to treat degenerative diseases of the lumbar spine; however, the scope of such surgery and vision is limited by what the naked eye can see through the expanding channel system. To expand the visual scope and reduce trauma, we perform lumbar intervertebral fusion with the aid of a MMED system that provides a wide field through freely tilting the surgical instrument and canals. We believe that this technique is a good option for treating lumbar degenerative disc disease that requires lumbar intervertebral fusion. PMID:27384734

  13. Intervertebral Fusion with Mobile Microendoscopic Discectomy for Lumbar Degenerative Disc Disease.

    PubMed

    Xu, Bao-Shan; Liu, Yue; Xu, Hai-Wei; Yang, Qiang; Ma, Xin-Long; Hu, Yong-Cheng

    2016-05-01

    The aim of this article is to introduce a technique for lumbar intervertebral fusion that incorporates mobile microendoscopic discectomy (MMED) for lumbar degenerative disc disease. Minimally invasive transforaminal lumbar interbody fusion is frequently performed to treat degenerative diseases of the lumbar spine; however, the scope of such surgery and vision is limited by what the naked eye can see through the expanding channel system. To expand the visual scope and reduce trauma, we perform lumbar intervertebral fusion with the aid of a MMED system that provides a wide field through freely tilting the surgical instrument and canals. We believe that this technique is a good option for treating lumbar degenerative disc disease that requires lumbar intervertebral fusion.

  14. Intraocular Radio-Opaque Ring.

    PubMed

    Shieh, Christine; Folz, Emily; Fekrat, Sharon

    2015-01-01

    A radiologist noted a radio-opaque object in the eye of a woman undergoing X-ray examination to determine the safety of magnetic resonance imaging (MRI). Water's X-ray shows the titanium locking c-ring of a type 1 Boston keratoprosthesis. This ring was added in 2004 to prevent intraocular disassembly of the device. The nonmagnetic ring does not prevent MRI imaging. The titanium locking c-ring and the titanium or polymethyl methacrylate back plate of the Boston keratoprosthesis are safe for MRI imaging. PMID:26271082

  15. Saturn's Rings Edge-on

    NASA Technical Reports Server (NTRS)

    1995-01-01

    In one of nature's most dramatic examples of 'now-you see-them, now-you-don't', NASA's Hubble Space Telescope captured Saturn on May 22, 1995 as the planet's magnificent ring system turned edge-on. This ring-plane crossing occurs approximately every 15 years when the Earth passes through Saturn's ring plane.

    For comparison, the top picture was taken by Hubble on December 1, 1994 and shows the rings in a more familiar configuration for Earth observers.

    The bottom picture was taken shortly before the ring plane crossing. The rings do not disappear completely because the edge of the rings reflects sunlight. The dark band across the middle of Saturn is the shadow of the rings cast on the planet (the Sun is almost 3 degrees above the ring plane.) The bright stripe directly above the ring shadow is caused by sunlight reflected off the rings onto Saturn's atmosphere. Two of Saturn's icy moons are visible as tiny starlike objects in or near the ring plane. They are, from left to right, Tethys (slightly above the ring plane) and Dione.

    This observation will be used to determine the time of ring-plane crossing and the thickness of the main rings and to search for as yet undiscovered satellites. Knowledge of the exact time of ring-plane crossing will lead to an improved determination of the rate at which Saturn 'wobbles' about its axis (polar precession).

    Both pictures were taken with Hubble's Wide Field Planetary Camera 2. The top image was taken in visible light. Saturn's disk appears different in the bottom image because a narrowband filter (which only lets through light that is not absorbed by methane gas in Saturn's atmosphere) was used to reduce the bright glare of the planet. Though Saturn is approximately 900 million miles away, Hubble can see details as small as 450 miles across.

    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

  16. Split ring containment attachment device

    DOEpatents

    Sammel, Alfred G.

    1996-01-01

    A containment attachment device 10 for operatively connecting a glovebag 200 to plastic sheeting 100 covering hazardous material. The device 10 includes an inner split ring member 20 connected on one end 22 to a middle ring member 30 wherein the free end 21 of the split ring member 20 is inserted through a slit 101 in the plastic sheeting 100 to captively engage a generally circular portion of the plastic sheeting 100. A collar potion 41 having an outer ring portion 42 is provided with fastening means 51 for securing the device 10 together wherein the glovebag 200 is operatively connected to the collar portion 41.

  17. Statistical ring current of Saturn

    NASA Astrophysics Data System (ADS)

    Carbary, J. F.; Achilleos, N.; Arridge, C. S.

    2012-06-01

    The statistical ring current of Saturn has been determined from the curl of the median magnetic field derived from over 5 years of observations of the Cassini magnetometer. The main issue addressed here is the calculation of the statistical ring current of Saturn by directly computing, for the first time, the symmetrical part of the ring current J from the Maxwell equation ∇ × B = μ0J from assembling the perturbation magnetic field B from 2004 through 2010. This study validates previous studies, based on fewer data and not using ∇ × B, and shows that the ring current flows eastward (in the +ϕ or corotation direction) and extends from ˜3 RS to at least ˜20 RS (1 RS = 60,268 km), which is the vicinity of the dayside magnetopause; that the ring current has a peak strength of ˜75 pA/m2 at ˜9.5 RS; and that the ring current has a half-width of ˜1.5 RS. Two outcomes of this study are that the ring current bends northward, as suggested by the “bowl” model of Saturn's plasma sheet, and that the total ring current is 9.2 ± 1.0 MA. In the context of future endeavors, the statistical ring current presented here can be used for calculations of the magnetic field of Saturn for particle drifts, field line mapping, and J × B force.

  18. Formation of lunar basin rings

    USGS Publications Warehouse

    Hodges, C.A.; Wilhelms, D.E.

    1978-01-01

    The origin of the multiple concentric rings that characterize lunar impact basins, and the probable depth and diameter of the transient crater have been widely debated. As an alternative to prevailing "megaterrace" hypotheses, we propose that the outer scarps or mountain rings that delineate the topographic rims of basins-the Cordilleran at Orientale, the Apennine at Imbrium, and the Altai at Nectaris-define the transient cavities, enlarged relatively little by slumping, and thus are analogous to the rim crests of craters like Copernicus; inner rings are uplifted rims of craters nested within the transient cavity. The magnitude of slumping that occurs on all scarps is insufficient to produce major inner rings from the outer. These conclusions are based largely on the observed gradational sequence in lunar central uplifts:. from simple peaks through somewhat annular clusters of peaks, peak and ring combinations and double ring basins, culminating in multiring structures that may also include peaks. In contrast, belts of slump terraces are not gradational with inner rings. Terrestrial analogs suggest two possible mechanisms for producing rings. In some cases, peaks may expand into rings as material is ejected from their cores, as apparently occurred at Gosses Bluff, Australia. A second process, differential excavation of lithologically diverse layers, has produced nested experimental craters and is, we suspect, instrumental in the formation of terrestrial ringed impact craters. Peak expansion could produce double-ring structures in homogeneous materials, but differential excavation is probably required to produce multiring and peak-in-ring configurations in large lunar impact structures. Our interpretation of the representative lunar multiring basin Orientale is consistent with formation of three rings in three layers detected seismically in part of the Moon-the Cordillera (basin-bounding) ring in the upper crust, the composite Montes Rook ring in the underlying

  19. Ground Movement in SSRL Ring

    SciTech Connect

    Sunikumar, Nikita; /UCLA /SLAC

    2011-08-25

    Users of the Stanford Synchrotron Radiation Lightsource (SSRL) are being affected by diurnal motion of the synchrotron's storage ring, which undergoes structural changes due to outdoor temperature fluctuations. In order to minimize the effects of diurnal temperature fluctuations, especially on the vertical motion of the ring floor, scientists at SSRL tried three approaches: painting the storage ring white, covering the asphalt in the middle of the ring with highly reflective Mylar and installing Mylar on a portion of the ring roof and walls. Vertical motion in the storage ring is measured by a Hydrostatic Leveling System (HLS), which calculates the relative height of water in a pipe that extends around the ring. The 24-hr amplitude of the floor motion was determined using spectral analysis of HLS data, and the ratio of this amplitude before and after each experiment was used to quantitatively determine the efficacy of each approach. The results of this analysis showed that the Mylar did not have any significant effect on floor motion, although the whitewash project did yield a reduction in overall HLS variation of 15 percent. However, further analysis showed that the reduction can largely be attributed to a few local changes rather than an overall reduction in floor motion around the ring. Future work will consist of identifying and selectively insulating these local regions in order to find the driving force behind diurnal floor motion in the storage ring.

  20. Origin of outer rings in lunar multi-ringed basins - Evidence from morphology and ring spacing

    NASA Technical Reports Server (NTRS)

    Head, J. W.

    1977-01-01

    The reported investigation has the objective to examine both the morphology and morphometry of several of the freshest lunar basins including Orientale, Imbrium, Nectaris, Crisium, and Humorum, and to compare the characteristics of their three most prominent rings to features in smaller craters. On the basis of comparisons it is concluded that the outer basin ring forms within the region where significant structural uplift of the basin rim is to be expected. Therefore the formation of the outer ring scarp may be closely associated with structural uplift of the inner portion of the crater rim flank. According to a model suggested for the origin of the outer two rings, the cratering event formed two inner rings, a central peak ring, and an uplifted crater rim crest, with deposition of ejecta during the process.

  1. Black ring deconstruction

    SciTech Connect

    Gimon, Eric; Gimon, Eric G.; Levi, Thomas S.

    2007-06-22

    We present a sample microstate for a black ring in four and five dimensional language. The microstate consists of a black string microstate with an additional D6-brane. We show that with an appropriate choice of parameters the piece involving the black string microstate falls down a long AdS throat, whose M-theory lift is AdS_3 x S2. We wrap a spinning dipole M2-brane on the S2 in the probe approximation. In IIA, this corresponds to a dielectric D2-brane carrying only D0-charge. We conjecture this is the firstapproximation to a cloud of D0-branes blowing up due to their non-abelian degrees of freedom and the Myers effect.

  2. The Saturn Ring Observer: In situ studies of planetary rings

    NASA Astrophysics Data System (ADS)

    Nicholson, P. D.; Tiscareno, M. S.; Spilker, L. J.

    2010-12-01

    As part of the Planetary Science Decadal Survey recently undertaken by the NRC's Space Studies Board for the National Academy of Sciences, studies were commissioned for a number of potential missions to outer planet targets. One of these studies examined the technological feasibility of a mission to carry out in situ studies of Saturn's rings, from a spacecraft placed in a circular orbit above the ring plane: the Saturn Ring Observer. The technical findings and background are discussed in a companion poster by T. R. Spilker et al. Here we outline the science goals of such a mission. Most of the fundamental interactions in planetary rings occur on spatial scales that are unresolved by flyby or orbiter spacecraft. Typical particle sizes in the rings of Saturn are in the 1 cm - 10 m range, and average interparticle spacings are a few meters. Indirect evidence indicates that the vertical thickness of the rings is as little as 5 - 10 m, which implies a velocity dispersion of only a few mm/sec. Theories of ring structure and evolution depend on the unknown characteristics of interparticle collisions and on the size distribution of the ring particles. The SRO could provide direct measurements of both the coefficient of restitution -- by monitoring individual collisions -- and the particles’ velocity dispersion. High-resolution observations of individual ring particles should also permit estimates of their spin states. Numerical simulations of Saturn’s rings incorporating both collisions and self-gravity predict that the ring particles are not uniformly distributed, but are instead clustered into elongated structures referred to as “self-gravity wakes”, which are continually created and destroyed on an orbital timescale. Theory indicates that the average separation between wakes in the A ring is of order 30-100 m. Direct imaging of self-gravity wakes, including their formation and subsequent dissolution, would provide critical validation of these models. Other

  3. Magnetic fields in ring galaxies

    NASA Astrophysics Data System (ADS)

    Moss, D.; Mikhailov, E.; Silchenko, O.; Sokoloff, D.; Horellou, C.; Beck, R.

    2016-07-01

    Context. Many galaxies contain magnetic fields supported by galactic dynamo action. The investigation of these magnetic fields can be helpful for understanding galactic evolution; however, nothing definitive is known about magnetic fields in ring galaxies. Aims: Here we investigate large-scale magnetic fields in a previously unexplored context, namely ring galaxies, and concentrate our efforts on the structures that appear most promising for galactic dynamo action, i.e. outer star-forming rings in visually unbarred galaxies. Methods: We use tested methods for modelling α-Ω galactic dynamos, taking into account the available observational information concerning ionized interstellar matter in ring galaxies. Results: Our main result is that dynamo drivers in ring galaxies are strong enough to excite large-scale magnetic fields in the ring galaxies studied. The variety of dynamo driven magnetic configurations in ring galaxies obtained in our modelling is much richer than that found in classical spiral galaxies. In particular, various long-lived transients are possible. An especially interesting case is that of NGC 4513, where the ring counter-rotates with respect to the disc. Strong shear in the region between the disc and the ring is associated with unusually strong dynamo drivers in such counter-rotators. The effect of the strong drivers is found to be unexpectedly moderate. With counter-rotation in the disc, a generic model shows that a steady mixed parity magnetic configuration that is unknown for classical spiral galaxies, may be excited, although we do not specifically model NGC 4513. Conclusions: We deduce that ring galaxies constitute a morphological class of galaxies in which identification of large-scale magnetic fields from observations of polarized radio emission, as well as dynamo modelling, may be possible. Such studies have the potential to throw additional light on the physical nature of rings, their lifetimes, and evolution.

  4. [Major vascular complications following surgery for a herniated lumbar disk].

    PubMed

    Abad, C; Martel, D; Feijóo, J J; Carreira, L

    1993-01-01

    Two cases of arterial injury of the iliac arteries during surgery of the lumbar disc are presented. Both patients were successfully operated, in the first case a primary repair was accomplished, the second patient was treated by means of an ileo-femoral bypass graft. A comment of the pathophysiology, diagnostic and surgical management of this unusual complication is presented. PMID:8285363

  5. Enhanced muscle activity during lumbar extension exercise with pelvic stabilization.

    PubMed

    Lee, Ho-Seong

    2015-12-01

    The purpose of this study was to investigate whether pelvic stabilization affects multifidus (MF) and iliocostalis lumborum (IL) muscle activities during dynamic extension exercise. Nine males (age, 25.1±6.3 yr; height, 176.6±2.4 cm; body mass, 74.9±6.7 kg) performed an isometric lumbar extension strength test and dynamic exercise in an upright seated position with or without pelvic stabilization. The electromyography and muscle strength of the MF and IL muscles were measured when the subjects performed the isometric lumbar extension strength test at the trunk angle 110°, 146°, and 182°. In addition, the trunk extensor muscle activities were measured using 50% muscle strength of maximum isometric strength during a dynamic trunk extension exercise. The MF and IL muscle activities were significantly higher at 110°, 146°, and 182° with pelvic stabilization than that without pelvic stabilization during the isometric lumbar extension strength test (P<0.05) and the dynamic exercise (P<0.05). These results suggest that the lumbar extension exercise with pelvic stabilization may be more effective for MF and IL muscle activity compared to that without pelvic stabilization.

  6. 49 CFR 572.9 - Lumbar spine, abdomen, and pelvis.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...″ cap screw holes and attach the front mounting at the femur axial rotation joint. Tighten the mountings so that the pelvic-lumbar adapter is horizontal and adjust the femur friction plungers at each hip socket joint to 240 inch-pounds torque. (3) Flex the thorax forward 50° and then rearward as necessary...

  7. 49 CFR 572.9 - Lumbar spine, abdomen, and pelvis.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...″ cap screw holes and attach the front mounting at the femur axial rotation joint. Tighten the mountings so that the pelvic-lumbar adapter is horizontal and adjust the femur friction plungers at each hip socket joint to 240 inch-pounds torque. (3) Flex the thorax forward 50° and then rearward as necessary...

  8. 49 CFR 572.9 - Lumbar spine, abdomen, and pelvis.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...″ cap screw holes and attach the front mounting at the femur axial rotation joint. Tighten the mountings so that the pelvic-lumbar adapter is horizontal and adjust the femur friction plungers at each hip socket joint to 240 inch-pounds torque. (3) Flex the thorax forward 50° and then rearward as necessary...

  9. 49 CFR 572.9 - Lumbar spine, abdomen, and pelvis.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...″ cap screw holes and attach the front mounting at the femur axial rotation joint. Tighten the mountings so that the pelvic-lumbar adapter is horizontal and adjust the femur friction plungers at each hip socket joint to 240 inch-pounds torque. (3) Flex the thorax forward 50° and then rearward as necessary...

  10. 49 CFR 572.9 - Lumbar spine, abdomen, and pelvis.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...″ cap screw holes and attach the front mounting at the femur axial rotation joint. Tighten the mountings so that the pelvic-lumbar adapter is horizontal and adjust the femur friction plungers at each hip socket joint to 240 inch-pounds torque. (3) Flex the thorax forward 50° and then rearward as necessary...

  11. Retrolisthesis as a Compensatory Mechanism in Degenerative Lumbar Spine

    PubMed Central

    Jeon, Ikchan

    2015-01-01

    Objective Posterior vertebral translation as a type of spondylolisthesis, retrolisthesis is observed commonly in patients with degenerative spinal problems. Nevertheless, there is insufficient literature on retrolisthesis compared to anterolisthesis. The purpose of this study is to clarify the clinical features of retrolisthesis, and its developmental mechanism associated with a compensatory role in sagittal imbalance of the lumbar spine. Methods From 2003 to 2012, 230 Korean patients who underwent spinal surgery in our department under the impression of degenerative lumbar spinal disease were enrolled. All participants were divided into four groups : 35 patients with retrolisthesis (group R), 32 patients with simultaneous retrolisthesis and anterolisthesis (group R+A), 76 patients with anterolisthesis (group A), and 87 patients with non-translation (group N). The clinical features and the sagittal parameters related to retrolisthesis were retrospectively analyzed based on the patients' medical records. Results There were different clinical features and developmental mechanisms between retrolisthesis and anterolisthesis. The location of retrolisthesis was affected by the presence of simultaneous anterolisthesis, even though it predominantly manifest in L3. The relative lower pelvic incidence, pelvic tilt, and lumbar lordosis compared to anterolisthesis were related to the generation of retrolisthesis, with the opposite observations of patients with anterolisthesis. Conclusion Retrolisthesis acts as a compensatory mechanism for moving the gravity axis posteriorly for sagittal imbalance in the lumbar spine under low pelvic incidence and insufficient intra-spinal compensation. PMID:25810857

  12. Combined thrombin and autologous blood for repair of lumbar durotomy.

    PubMed

    Moussa, Wael Mohamed Mohamed; Aboul-Enein, Hisham A

    2016-10-01

    Lumbar durotomy can be intended or unintended and can result in persistent cerebrospinal fluid (CSF) leak. Several methods are used to manage this complication including bed rest and CSF diversion. In this study, we theorize that the use of thrombin-soaked gel foam together with autologous blood laid on the sutured dural tear can prevent persistent CSF leak. A retrospective review of the records of patients who underwent lumbar surgery and had an unintended dural tear with CSF leak, comparing the outcome of patients who were submitted to thrombin-soaked gel foam together with autologous blood (group A) to patients treated by subfacial drain, tight bandage, and bed rest (group B). A total of 1371 patients had lumbar surgery, of whom 131 had dural tear. Group A included 62 patients, while group B included 69 patients. 8.1 % of group A patients had CSF leak as compared to 17.4 % of group B patients at postoperative day 14. The incidence of postoperative CSF leak and duration of postoperative hospital stay were statistically lower in group A than in group B (p < 0.05). Combining thrombin and autologous blood for repair of lumbar durotomy is an effective and a relatively cheap way to decrease CSF leak in the early postoperative period as well as decreasing postoperative hospital stay. It also resulted in decreased complications rate in the late postoperative period. PMID:26864189

  13. Horner syndrome during lumbar epidural analgesia for obstetrics.

    PubMed

    Schachner, S M; Reynolds, A C

    1982-06-01

    Horner syndrome (ptosis, miosis, anhidrosis, and facial and conjunctival vasodilation) is a recognized complication of lumbar epidural analgesia for labor and delivery. Alone, it presents no significant risk to mother or fetus, as resolution is spontaneous and complete. Horner syndrome may, however, be associated with significant maternal hypotension and therefore should be an indication for close maternal and fetal monitoring to provide reassurance.

  14. Diagnosis and conservative management of degenerative lumbar spondylolisthesis

    PubMed Central

    Hunter, David J.

    2007-01-01

    Degenerative spondylolisthesis (DS) is a disorder that causes the slip of one vertebral body over the one below due to degenerative changes in the spine. Lumbar DS is a major cause of spinal canal stenosis and is often related to low back and leg pain. We reviewed the symptoms, prognosis and conservative treatments for symptoms associated with DS. PubMed and MEDLINE databases (1950–2007) were searched for the key words “spondylolisthesis”, “pseudospondylolisthesis”, “degenerative spondylolisthesis”, “spinal stenosis”, “lumbar spine”, “antherolisthesis”, “posterolisthesis”, “low back pain”, and “lumbar instability”. All relevant articles in English were reviewed. Pertinent secondary references were also retrieved. The prognosis of patients with DS is favorable, however, those who suffer from neurological symptoms such as intermittent claudication or vesicorectal disorder, will most probably experience neurological deterioration if they are not operated upon. Nonoperative treatment should be the initial course of action in most cases of DS, with or without neurologic symptoms. Treatment options include use of analgesics and NSAIDs to control pain; epidural steroid injections, and physical methods such as bracing and flexion strengthening exercises. An up-to-date knowledge on diagnosis and prevention of lumbar DS can assist in determination of future research goals. Additional studies are required to establish treatment protocols for the conservative treatment of DS. PMID:18026865

  15. Enhanced muscle activity during lumbar extension exercise with pelvic stabilization

    PubMed Central

    Lee, Ho-Seong

    2015-01-01

    The purpose of this study was to investigate whether pelvic stabilization affects multifidus (MF) and iliocostalis lumborum (IL) muscle activities during dynamic extension exercise. Nine males (age, 25.1±6.3 yr; height, 176.6±2.4 cm; body mass, 74.9±6.7 kg) performed an isometric lumbar extension strength test and dynamic exercise in an upright seated position with or without pelvic stabilization. The electromyography and muscle strength of the MF and IL muscles were measured when the subjects performed the isometric lumbar extension strength test at the trunk angle 110°, 146°, and 182°. In addition, the trunk extensor muscle activities were measured using 50% muscle strength of maximum isometric strength during a dynamic trunk extension exercise. The MF and IL muscle activities were significantly higher at 110°, 146°, and 182° with pelvic stabilization than that without pelvic stabilization during the isometric lumbar extension strength test (P<0.05) and the dynamic exercise (P<0.05). These results suggest that the lumbar extension exercise with pelvic stabilization may be more effective for MF and IL muscle activity compared to that without pelvic stabilization. PMID:26730390

  16. Obesity and recurrent intervertebral disc prolapse after lumbar microdiscectomy

    PubMed Central

    Syme, G; Swamy, GN; Nanjayan, S; Fowler, A; Calthorpe, D

    2014-01-01

    Introduction The primary aim of this study was to investigate the relationship between obesity and recurrent intervertebral disc prolapse (IDP) following lumbar microdiscectomy. Methods A retrospective review of case notes from 2008 to 2012 was conducted for all patients who underwent single level lumbar microdiscectomy performed by a single surgeon. All patients were followed up at two weeks and six weeks following surgery, and given an open appointment for a further six months. Results A total of 283 patients were available for analysis: 190 (67%) were in the non-obese group and 93 (32.9%) in the obese group. There was no statistical difference in postoperative infection, dural tear or length of stay between the non-obese and obese groups. Recurrent symptomatic IDP was seen in 27 patients (9.5%) confirmed by magnetic resonance imaging. Nineteen (10.0%) were in the non-obese group and eight (8.6%) in the obese group (p>0.8). Conclusions In our study, obesity was not a predictor of recurrent IDP following lumbar microdiscectomy. Our literature review confirmed that this study reports the largest series to date analysing the relationship between obesity and recurrent IDP following lumbar microdiscectomy in the British population. PMID:24780673

  17. Iatrogenic neurologic deficit after lumbar spine surgery: A review.

    PubMed

    Ghobrial, George M; Williams, Kim A; Arnold, Paul; Fehlings, Michael; Harrop, James S

    2015-12-01

    Iatrogenic neurologic deficits after lumbar spine surgery are rare complications, but important to recognize and manage. Complications such as radiculopathy, spinal cord compression, motor deficits (i.e. foot drop with L5 radiculopathy), and new onset radiculitis, while uncommon do occur. Attempts at mitigating these complications with the use of neuromonitoring have been successful. Guidance in the literature as to the true rate of iatrogenic neurologic deficit is limited to several case studies and retrospective designed studies describing the management, prevention and treatment of these deficits. The authors review the lumbar spinal surgery literature to examine the incidence of iatrogenic neurologic deficit in the lumbar spinal surgery literature. An advanced MEDLINE search conducted on May 14th, 2015 from January 1, 2004 through May 14, 2015, using the following MeSH search terms "postoperative complications," then subterms "lumbar vertebrae," treatment outcome," "spinal fusion," and "radiculopathy" were included together with "postoperative complications" in a single search. Postoperative complications including radiculopathy, weakness, and spinal cord compression were included. The definition of iatrogenic neurologic complication was limited to post-operative radiculopathy, motor weakness or new onset pain/radiculitis. An advanced MEDLINE search conducted on May 14th, 2015 using all of the above terms together yielded 21 results. After careful evaluation, 11 manuscripts were excluded and 10 were carefully reviewed. The most common indications for surgery were degenerative spondylolisthesis, spondylosis, scoliosis, and lumbar stenosis. In 2783 patients in 12 total studies, there were 56 patients who had reported a postoperative neurologic deficit for a rate of 5.7. The rates of deficits ranged from 0.46% to 17% in the studies used. The average rate of reported neurologic complications within these papers was 9% (range 0.46-24%). Thirty patients of a total of

  18. Reversible Seeding in Storage Rings

    SciTech Connect

    Ratner, Daniel; Chao, Alex; /SLAC

    2011-12-14

    We propose to generate steady-state microbunching in a storage ring with a reversible seeding scheme. High gain harmonic generation (HGHG) and echo-enabled harmonic generation (EEHG) are two promising methods for microbunching linac electron beams. Because both schemes increase the energy spread of the seeded beam, they cannot drive a coherent radiator turn-by-turn in a storage ring. However, reversing the seeding process following the radiator minimizes the impact on the electron beam and may allow coherent radiation at or near the storage ring repetition rate. In this paper we describe the general idea and outline a proof-of-principle experiment. Electron storage rings can drive high average power light sources, and free-electron lasers (FELs) are now producing coherent light sources of unprecedented peak brightness While there is active research towards high repetition rate FELs (for example, using energy recovery linacs), at present there are still no convenient accelerator-based sources of high repetition rate, coherent radiation. As an alternative avenue, we recently proposed to establish steady-state microbunching (SSMB) in a storage ring. By maintaining steady-state coherent microbunching at one point in the storage ring, the beam generates coherent radiation at or close to the repetition rate of the storage ring. In this paper, we propose a method of generating a microbunched beam in a storage ring by using reversible versions of linac seeding schemes.

  19. Biomechanics of Corneal Ring Implants

    PubMed Central

    2015-01-01

    Purpose: To evaluate the biomechanics of corneal ring implants by providing a related mathematical theory and biomechanical model for the treatment of myopia and keratoconus. Methods: The spherical dome model considers the inhomogeneity of the tunica of the eye, dimensions of the cornea, lamellar structure of the corneal stroma, and asphericity of the cornea. It is used in this study for calculating a strengthening factor sf for the characterization of different ring-shaped corneal implant designs. The strengthening factor is a measure of the amount of strengthening of the cornea induced by the implant. Results: For ring segments and incomplete rings, sf = 1.0, which indicates that these implants are not able to strengthen the cornea. The intracorneal continuous complete ring (MyoRing) has a strengthening factor of up to sf = 3.2. The MyoRing is, therefore, able to strengthen the cornea significantly. Conclusions: The result of the presented biomechanical analysis of different ring-shaped corneal implant designs can explain the different postoperative clinical results of different implant types in myopia and keratoconus. PMID:26312619

  20. Running Rings Around the Web.

    ERIC Educational Resources Information Center

    McDermott, Irene E.

    1999-01-01

    Describes the development and current status of WebRing, a service that links related Web sites into a central hub. Discusses it as a viable alternative to other search engines and examines issues of free speech, use by the business sector, and implications for WebRing after its purchase by Yahoo! (LRW)

  1. How Jupiter's Ring Was Discovered.

    ERIC Educational Resources Information Center

    Elliot, James; Kerr, Richard

    1985-01-01

    "Rings" (by astronomer James Elliot and science writer Richard Kerr) is a nontechnical book about the discovery and exploration of ring systems from the time of Galileo to the era of the Voyager spacecraft. One of this book's chapters is presented. (JN)

  2. Fibre ring cavity semiconductor laser

    SciTech Connect

    Duraev, V P; Medvedev, S V

    2013-10-31

    This paper presents a study of semiconductor lasers having a polarisation maintaining fibre ring cavity. We examine the operating principle and report main characteristics of a semiconductor ring laser, in particular in single- and multiple-frequency regimes, and discuss its application areas. (lasers)

  3. Retroperitoneoscopic Lumbar Sympathectomy for Buerger's Disease: A Novel Technique

    PubMed Central

    Singh, Lakhvinder; Lal, Pawan; Jain, Akhilesh; Lal, Pawanindra; Ramteke, V. K.

    2004-01-01

    Background: The conventional lumbar sympathectomy procedure through the extraperitoneal route requires a muscle cutting-splitting incision, which leads to significant postoperative pain and prolonged convalescence. With increasing experience in retroperitoneoscopic procedures, we did a pilot study to explore the role of retroperitoneoscopy in lumbar sympathectomy. We describe herein our technique used for the surgery. Methods: The patient was placed in a lateral position. A 15-mm incision was made just below the 12th rib, and retroperitoneal space was created using blunt finger dissection. A custom-made, large balloon was inserted and inflated with the equivalent of 750 mL to 1000 mL of saline. The second 10-mm port was placed in line with the first port above the iliac crest. The third and fourth 5-mm ports were placed anterior to the first 2 ports. Peritoneum was retracted anteriorly. The medial border of the psoas muscle was used as a landmark and a chain identified immediately medial to it. Lumbar vessels were ligated on the right side. The first to fourth lumbar sympathetic ganglia were removed with the intervening chain. The port sites were closed without a drain. Results: We attempted and successfully completed this procedure in 8 patients; 6 on the left side and 2 on the right side. The average operating time was 38 minutes. The mean hospital stay was 1.5 days. All patients had symptomatic pain relief and clinical improvement. Conclusions: Retroperitoneoscopic lumbar sympathectomy is a safe and effective procedure. It has a short convalescent time and minimal morbidity; hence, it is a viable alternative for the open procedure. PMID:15347122

  4. The rare-RI ring

    NASA Astrophysics Data System (ADS)

    Ozawa, A.; Uesaka, T.; Wakasugi, M.; Rare-RI Ring Collaboration

    2012-12-01

    We describe the rare-RI (radioactive isotope) ring at the RI Beam Factory (RIBF). The main purpose of the rare-RI ring is to measure the mass of very neutron-rich nuclei, the production rates of which are very small (hence ‘rare RI’) and the lifetimes of which are predicted to be very short. In the rare-RI ring, there are two innovative pieces of apparatus: individual injection, which can realize the injection of 200 A MeV rare RIs one by one, and a cyclotron-like storage ring, which allows high isochronous magnetic fields with large angular and momentum acceptances. With these devices, we will achieve a 10-6 mass resolution, and will be able to access rare RIs, the production rate of which is down to 1 event/day/pnA. Construction of the rare-RI ring started in fiscal year 2012.

  5. 21 CFR 880.6200 - Ring cutter.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ring cutter. 880.6200 Section 880.6200 Food and....6200 Ring cutter. (a) Identification. A ring cutter is a device intended for medical purposes that is used to cut a ring on a patient's finger so that the ring can be removed. The device incorporates...

  6. 21 CFR 880.6200 - Ring cutter.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Ring cutter. 880.6200 Section 880.6200 Food and....6200 Ring cutter. (a) Identification. A ring cutter is a device intended for medical purposes that is used to cut a ring on a patient's finger so that the ring can be removed. The device incorporates...

  7. 21 CFR 880.6200 - Ring cutter.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Ring cutter. 880.6200 Section 880.6200 Food and....6200 Ring cutter. (a) Identification. A ring cutter is a device intended for medical purposes that is used to cut a ring on a patient's finger so that the ring can be removed. The device incorporates...

  8. 21 CFR 880.6200 - Ring cutter.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Ring cutter. 880.6200 Section 880.6200 Food and....6200 Ring cutter. (a) Identification. A ring cutter is a device intended for medical purposes that is used to cut a ring on a patient's finger so that the ring can be removed. The device incorporates...

  9. 21 CFR 880.6200 - Ring cutter.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Ring cutter. 880.6200 Section 880.6200 Food and....6200 Ring cutter. (a) Identification. A ring cutter is a device intended for medical purposes that is used to cut a ring on a patient's finger so that the ring can be removed. The device incorporates...

  10. Diagnostic challenge: bilateral infected lumbar facet cysts - a rare cause of acute lumbar spinal stenosis and back pain

    PubMed Central

    2010-01-01

    Symptomatic synovial lumbar facet cysts are a relatively rare cause of radiculopathy and spinal stenosis. This case and brief review of the literature, details a patient who presented with acutely symptomatic bilateral spontaneously infected synovial facet (L4/5) cysts. This report highlights diagnostic clues for identifying infection of a facet cyst. PMID:20205727

  11. Useful Points of Geometry and Topography of the Lumbar Triangle for Transversus Abdominis Plane Block

    PubMed Central

    Ziętek, Zbigniew; Starczewski, Kamil; Sulikowski, Tadeusz; Iwan-Ziętek, Iza; Żukowski, Maciej; Kamiński, Marek; Ziętek-Czeszak, Angelika

    2015-01-01

    Background A new look at the topography of the lumbar triangle becomes a challenge for modern anesthesia. The aim of this study was to redefine the topography of the lumbar triangle for transverse abdominis plane block. Material/Methods We explored 74 lumbar regions in 37 preserved cadavers (17 F and 20 M). Results The lumbar triangle was identified in 66 (89%) out of all explored cadavers’ lumbar regions. The predominant triangle was the acute-angled shaped. It was identified in 39 (59%) out of all explored lumbar regions. The second type of dissected triangles had the obtuse-angled shaped. Most triangles of acute-angled shaped and obtuse-angled shaped (36) had medium surface (range from 3 cm2 to 6 cm2), which accounted for 55% of all dissected lumbar triangles. The mean surface of the lumbar triangle was 3.6±2.2 cm2. Based on other measurements, we demonstrated that the majority of the lumbar triangles (62 triangles) were beyond the posterior axillary line. Conclusions According to the obtained results, the randomized searching for lumbar triangle should be limited to the area situated beyond of the posterior axillary line. The region situated anteriorly to the midaxillary line was defined in the study as the critical area for finding the lumbar triangle. Outcomes from the study revealed that the size and the location of the lumbar triangle as the gate for the transverse abdominal plane block may be responsible for difficulties encountered by anesthetists. Thus, establishing the area with the highest probability of localization of the lumbar triangle can improve both safety and efficiency of transversus abdominis plane block. PMID:26714659

  12. Ring Buffered Network Bus

    NASA Technical Reports Server (NTRS)

    1997-01-01

    This report describes the research effort to demonstrate the integration of a data sharing technology, Ring Buffered Network Bus, in development by Dryden Flight Research Center, with an engine simulation application, the Java Gas Turbine Simulator, in development at the University of Toledo under a grant from the Glenn Research Center. The objective of this task was to examine the application of the RBNB technologies as a key component in the data sharing, health monitoring and system wide modeling elements of the NASA Aviation Safety Program (AVSP) [Golding, 1997]. System-wide monitoring and modeling of aircraft and air safety systems will require access to all data sources which are relative factors when monitoring or modeling the national airspace such as radar, weather, aircraft performance, engine performance, schedule and planning, airport configuration, flight operations, etc. The data sharing portion of the overall AVSP program is responsible for providing the hardware and software architecture to access and distribute data, including real-time flight operations data, among all of the AVSP elements. The integration of an engine code capable of numerically "flying" through recorded flight paths and weather data using a software tool that allows for distributed access of data to this engine code demonstrates initial steps toward building a system capable of monitoring and modeling the National Airspace.

  13. Ion Rings for Magnetic Fusion

    SciTech Connect

    Greenly, John, B.

    2005-07-31

    This Final Technical Report presents the results of the program, Ion Rings for Magnetic Fusion, which was carried out under Department of Energy funding during the period August, 1993 to January, 2005. The central objective of the program was to study the properties of field-reversed configurations formed by ion rings. In order to reach this objective, our experimental program, called the Field-reversed Ion Ring Experiment, FIREX, undertook to develop an efficient, economical technology for the production of field-reversed ion rings. A field-reversed configuration (FRC) in which the azimuthal (field-reversing) current is carried by ions with gyro-radius comparable to the magnetic separatrix radius is called a field-reversed ion ring. A background plasma is required for charge neutralization of the ring, and this plasma will be confined within the ring's closed magnetic flux. Ion rings have long been of interest as the basis of compact magnetic fusion reactors, as the basis for a high-power accelerator for an inertial fusion driver, and for other applications of high power ion beams or plasmas of high energy density. Specifically, the FIREX program was intended to address the longstanding question of the contribution of large-orbit ions to the observed stability of experimental FRCs to the MHD tilt mode. Typical experimental FRCs with s {approx} 2-4, where s is the ratio of separatrix radius to ion gyro-radius, have been stable to tilting, but desired values for a fusion reactor, s > 20, should be unstable. The FIREX ring would consist of a plasma with large s for the background ions, but with s {approx} 1 for the ring ions. By varying the proportions of these two populations, the minimum proportion of large-orbit ions necessary for stability could be determined. The incorporation of large-orbit ions, perhaps by neutral-beam injection, into an FRC has been advanced for the purpose of stabilizing, heating, controlling angular momentum, and aiding the formation of a

  14. Cumulative occupational lumbar load and lumbar disc disease – results of a German multi-center case-control study (EPILIFT)

    PubMed Central

    Seidler, Andreas; Bergmann, Annekatrin; Jäger, Matthias; Ellegast, Rolf; Ditchen, Dirk; Elsner, Gine; Grifka, Joachim; Haerting, Johannes; Hofmann, Friedrich; Linhardt, Oliver; Luttmann, Alwin; Michaelis, Martina; Petereit-Haack, Gabriela; Schumann, Barbara; Bolm-Audorff, Ulrich

    2009-01-01

    Background The to date evidence for a dose-response relationship between physical workload and the development of lumbar disc diseases is limited. We therefore investigated the possible etiologic relevance of cumulative occupational lumbar load to lumbar disc diseases in a multi-center case-control study. Methods In four study regions in Germany (Frankfurt/Main, Freiburg, Halle/Saale, Regensburg), patients seeking medical care for pain associated with clinically and radiologically verified lumbar disc herniation (286 males, 278 females) or symptomatic lumbar disc narrowing (145 males, 206 females) were prospectively recruited. Population control subjects (453 males and 448 females) were drawn from the regional population registers. Cases and control subjects were between 25 and 70 years of age. In a structured personal interview, a complete occupational history was elicited to identify subjects with certain minimum workloads. On the basis of job task-specific supplementary surveys performed by technical experts, the situational lumbar load represented by the compressive force at the lumbosacral disc was determined via biomechanical model calculations for any working situation with object handling and load-intensive postures during the total working life. For this analysis, all manual handling of objects of about 5 kilograms or more and postures with trunk inclination of 20 degrees or more are included in the calculation of cumulative lumbar load. Confounder selection was based on biologic plausibility and on the change-in-estimate criterion. Odds ratios (OR) and 95% confidence intervals (CI) were calculated separately for men and women using unconditional logistic regression analysis, adjusted for age, region, and unemployment as major life event (in males) or psychosocial strain at work (in females), respectively. To further elucidate the contribution of past physical workload to the development of lumbar disc diseases, we performed lag-time analyses. Results We

  15. Particle properties and processes in Uranus' rings

    NASA Technical Reports Server (NTRS)

    Esposito, L. W.; Brahic, A.; Burns, J. A.; Marouf, Essam A.

    1991-01-01

    The particle properties and processes in the Uranian rings are analyzed from Voyager observations and ground-based data. Occultation observations of the epsilon ring are interpreted to yield an effective size of the ring particles that exceeds 70 cm, a surface mass density that exceeds 80 g/sq cm, and a ring vertical thickness greater than tens of meters for solid ice particles. The particles forming the classic rings are dark and gray, with albedo of 0.014 +/-0.004. It is argued that the small amount of dust that exists in the classical rings and between the rings in bands is created by erosion of ring particles and unseen satellites resulting from collisions and micrometeoroid bombardment. As proposed for regions of the other known ring systems, new ring material can be continually created by the destruction of small moons near the rings, which may explain the youthful appearance of the Uranian rings.

  16. Entrainment in interacting vortex rings

    NASA Astrophysics Data System (ADS)

    Shami, Rammah; Ganapathisubramani, Bharathram

    2014-11-01

    The efficiency of entrainment in single vortex rings has been examined by various studies in the literature. These studies have shown that this efficiency is greatly increased for smaller stroke-time to nozzle-diameter ratios, L/D. However, no clear consensus exists regarding the effect on the entrainment process for the sectioned delivery of the vortex forming impulse. In the present work the entrainment mechanism associated with the interaction between two co-axially separated vortex rings is explored. Planar, time-resolved particle image velocimetry (PIV) measurements are taken of a interacting vortex flow field. Lagrangian coherent structures (LCS) extracted from the finite-time Lyapunov exponent (FTLE) fields are employed to determine the vortex boundaries of the interacting rings and is then used to measure entrainment. Preliminary results indicate that whilst the most efficient entrainment of ambient fluid by the ring pairs occurs at larger separations, the rate and overall mass transport increase can be controlled by altering the spatial/temporal separation between successive rings and is higher at smaller ring spacing. Variation in mass transport behaviour for different ring strengths (L/D) and Reynolds numbers will also be discussed.

  17. Modeling piston-ring dynamics, blowby, and ring-twist effects

    SciTech Connect

    Tian, T.; Noordzij, L.B.; Wong, V.W.; Heywood, J.B.

    1996-12-31

    A ring-dynamics and gas-flow model has been developed to study ring/groove contact, blowby, and the influence of ring static twist, keystone ring/groove configurations, and other piston and ring parameters. The model is developed for a ring pack with three rings. The dynamics of the top two rings and the gas pressures in the regions above the oil control ring are simulated. Distributions of oil film thickness and surface roughness on the groove and ring surfaces are assumed in the model to calculate the forces generated by the ring/groove contact. Ring static and dynamic twists are considered as well as different keystone ring/groove configurations. Ring dynamics and gas flows are coupled in the formulation and an implicit scheme is implemented, enabling the model to resolve detailed events such as ring flutter. Studies on a spark ignition engine found that static twist or, more generally speaking, the relative angle between rings and their grooves, has great influence on ring/groove contact characteristics, ring stability, and blowby. Ring flutter is found to occur for the second ring with a negative static twist under normal operating conditions and for the top ring with a negative static twist under high-speed/low-load operating conditions. Studies on a diesel engine show that different keystone ring/groove configurations result in different twist behaviors of the ring that may affect the wear pattern of the keystone ring running surfaces.

  18. Comments on collision mechanics in ring systems. [planetary rings

    NASA Technical Reports Server (NTRS)

    Hartmann, W. K.

    1982-01-01

    Collisions within planetary ring systems, especially Saturn's, are discussed. The particles may have coherent icy cores and less coherent granular or frosty surface layers, consistent with thermal eclipse observations. Collisions do not cause catastrophic fragmentation of the particles, although minor surface erosion and reaccretion is possible. Evolution by collisional fragmentation is thus not as important as in the asteroid belt. Models suggest that the fractional number of projectile masses dislodged when solid (or solid-core) projectiles strike solid ice or granular surface layers does not exceed the order of 10 to the minus 7th to minus 9th power. Even at this rate, the half life of ring particles would be less than the age of the solar system in crowded ring regions unless there was very efficient reaccretion. A plausible ring particle model involves solid ice cores with granular surface layers that exchange material by slow erosion and efficient reaccretion; the granular layers protect the cores from rapid erosion.

  19. Voyager 2 and the Uranian rings

    SciTech Connect

    Porco, C.C.

    1986-12-01

    Voyager 2 data on the Uranian disk system are presented and examined. The disk system consists of nine narrow rings, ranging in width from a few km to about 100 km. The Uranian rings are eccentric, inclined to the planet's equatorial plane, and precessing. The Uranian ring characteristics detected in the Voyager data are described and compared with those of the Saturn rings. The origin and maintenance of the rings are discussed, and the particle distribution in the ring system is studied.

  20. The role of resonances in planetary rings

    NASA Technical Reports Server (NTRS)

    Borderies, N.

    1987-01-01

    The new observations of planetary rings, including those acquired during the encounters of Voyager with Jupiter, Saturn, and Uranus, and the discovery of incomplete rings around Neptune, reveal the great importance of resonances in determining the dynamics and the shape of planetary rings. Several types of resonances play a part in planetary rings. Current questions of interest are related to the nonlinear theory of density waves, the confinement of the Uranian rings, and the arcs of rings around Neptune.

  1. Researches on the Piston Ring

    NASA Technical Reports Server (NTRS)

    Ehihara, Keikiti

    1944-01-01

    In internal combustion engines, steam engines, air compressors, and so forth, the piston ring plays an important role. Especially, the recent development of Diesel engines which require a high compression pressure for their working, makes, nowadays, the packing action of the piston ring far more important than ever. Though a number of papers have been published in regard to researches on the problem of the piston ring, none has yet dealt with an exact measurement of pressure exerted on the cylinder wall at any given point of the ring. The only paper that can be traced on this subject so far is Mr. Nakagawa's report on the determination of the relative distribution of pressure on the cylinder wall, but the measuring method adopted therein appears to need further consideration. No exact idea has yet been obtained as to how the obturation of gas between the piston and cylinder, the frictional resistance of the piston, and the wear of the cylinder wall are affected by the intensity and the distribution of the radial pressure of the piston ring. Consequently, the author has endeavored, by employing an apparatus of his own invention, to get an exact determination of the pressure distribution of the piston ring. By means of a newly devised ring tester, to which piezoelectricity of quartz was applied, the distribution of the radial pressure of many sample rings on the market was accurately determined. Since many famous piston rings show very irregular pressure distribution, the author investigated and achieved a manufacturing process of the piston ring which will exert uniform pressure on the cylinder wall. Temperature effects on the configuration and on the mean spring power have also been studied. Further, the tests were performed to ascertain how the gas tightness of the piston ring may be affected by the number or spring power. The researches as to the frictional resistance between the piston ring and the cylinder wall were carried out, too. The procedure of study, and

  2. Soft Congruence Relations over Rings

    PubMed Central

    Xin, Xiaolong; Li, Wenting

    2014-01-01

    Molodtsov introduced the concept of soft sets, which can be seen as a new mathematical tool for dealing with uncertainty. In this paper, we initiate the study of soft congruence relations by using the soft set theory. The notions of soft quotient rings, generalized soft ideals and generalized soft quotient rings, are introduced, and several related properties are investigated. Also, we obtain a one-to-one correspondence between soft congruence relations and idealistic soft rings and a one-to-one correspondence between soft congruence relations and soft ideals. In particular, the first, second, and third soft isomorphism theorems are established, respectively. PMID:24949493

  3. Reflex ring laser amplifier system

    DOEpatents

    Summers, Mark A.

    1985-01-01

    A laser pulse is injected into an unstable ring resonator-amplifier structure. Inside this resonator the laser pulse is amplified, spatially filtered and magnified. The laser pulse is recirculated in the resonator, being amplified, filtered and magnified on each pass. The magnification is chosen so that the beam passes through the amplifier in concentric non-overlapping regions similar to a single pass MOPA. After a number of passes around the ring resonator the laser pulse is spatially large enough to exit the ring resonator system by passing around an output mirror.

  4. Electromagnetic effects on planetary rings

    SciTech Connect

    Morfill, G.E.

    1983-01-01

    The role of electromagnetic effects in planetary rings is reviewed. The rings consist of a collection of solid particles with a size spectrum ranging from submicron to 10's of meters (at least in the case of Saturn's rings). Due to the interaction with the ambient plasma, and solar UV radiation, the particles carry electrical charges. Interactions of particles with the planetary electromagnetic field, both singly and collectively, are described, as well as the reactions and influence on plasma transients. The latter leads to a theory for the formation of Saturn's spokes, which is briefly reviewed.

  5. Codes over infinite family of rings : Equivalence and invariant ring

    NASA Astrophysics Data System (ADS)

    Irwansyah, Muchtadi-Alamsyah, Intan; Muchlis, Ahmad; Barra, Aleams; Suprijanto, Djoko

    2016-02-01

    In this paper, we study codes over the ring Bk=𝔽pr[v1,…,vk]/(vi2=vi,∀i =1 ,…,k ) . For instance, we focus on two topics, i.e. characterization of the equivalent condition between two codes over Bk using a Gray map into codes over finite field 𝔽pr, and finding generators for invariant ring of Hamming weight enumerator for Euclidean self-dual codes over Bk.

  6. Calibration method for lumbosacral dimensions in wearable sensor system of lumbar alignment.

    PubMed

    Tsuchiya, Yoshio; Kusaka, Takashi; Tanaka, Takayuki; Matsuo, Yoshikazu; Oda, Makoto; Sasaki, Tsukasa; Kamishima, Tamotsu; Yamanaka, Masanori

    2015-01-01

    Anteflexion of the spine is essential for many physical activities in everyday life. However, this motion places the lumbar disks under heavy load due to changes in the shape of the lumbar spine and can lead to low back pain. With the aim of reducing low back pain, here we developed a wearable sensor system that can estimate lumbosacral alignment and lumbar load by measuring the shape of the lumbar skin when the lumbosacral alignment changes. In addition, we used this system to measure the parameters of anteflexion and studied the change in dimensions of the lumbar spine from changes in posture. By determining the dimensions of the lumbosacral spine on an X-ray image, a lumbosacral dimensions calibration method based on body surface area and height was developed. By using this method, lumbosacral alignment and lumbar load could be accurately estimated using the wearable sensor system.

  7. The Microendoscopic Decompression of Lumbar Stenosis: A Review of the Current Literature and Clinical Results

    PubMed Central

    Wong, Albert P.; Smith, Zachary A.; Lall, Rohan R.; Bresnahan, Lacey E.; Fessler, Richard G.

    2012-01-01

    Lumbar stenosis is a well-defined pathologic condition with excellent surgical outcomes. Empiric evidence as well as randomized, prospective trials has demonstrated the superior efficacy of surgery compared to medical management for lumbar stenosis. Traditionally, lumbar stenosis is decompressed with open laminectomies. This involves removal of the spinous process, lamina, and the posterior musculoligamentous complex (posterior tension band). This approach provides excellent improvement in symptoms, but is also associated with potential postoperative spinal instability. This may result in subsequent need for spinal fusion. Advances in technology have enabled the application of minimally invasive spine surgery (MISS) as an acceptable alternative to open lumbar decompression. Recent studies have shown similar to improved perioperative outcomes when comparing MISS to open decompression for lumbar stenosis. A literature review of MISS for decompression of lumbar stenosis with tubular retractors was performed to evaluate the outcomes of this modern surgical technique. In addition, a discussion of the advantages and limitations of this technique is provided. PMID:22900163

  8. Of Rings and Volcanoes

    NASA Astrophysics Data System (ADS)

    2002-01-01

    Office National d'Etudes et de Recherches Aérospatiales (ONERA) , Laboratoire d'Astrophysique de Grenoble (LAOG) and the DESPA and DASGAL laboratories of the Observatoire de Paris in France, in collaboration with ESO. The CONICA infra-red camera was built, under an ESO contract, by the Max-Planck-Institut für Astronomie (MPIA) (Heidelberg) and the Max-Planck Institut für Extraterrestrische Physik (MPE) (Garching) in Germany, in collaboration with ESO. Saturn - Lord of the rings ESO PR Photo 04a/02 ESO PR Photo 04a/02 [Preview - JPEG: 460 x 400 pix - 54k] [Normal - JPEG: 1034 x 800 pix - 200k] Caption : PR Photo 04a/02 shows the giant planet Saturn, as observed with the VLT NAOS-CONICA Adaptive Optics instrument on December 8, 2001; the distance was 1209 million km. It is a composite of exposures in two near-infrared wavebands (H and K) and displays well the intricate, banded structure of the planetary atmosphere and the rings. Note also the dark spot at the south pole at the bottom of the image. One of the moons, Tethys, is visible as a small point of light below the planet. It was used to guide the telescope and to perform the adaptive optics "refocussing" for this observation. More details in the text. Technical information about this photo is available below. This NAOS/CONICA image of Saturn ( PR Photo 04a/02 ), the second-largest planet in the solar system, was obtained at a time when Saturn was close to summer solstice in the southern hemisphere. At this moment, the tilt of the rings was about as large as it can be, allowing the best possible view of the planet's South Pole. That area was on Saturn's night side in 1982 and could therefore not be photographed during the Voyager encounter. The dark spot close to the South Pole is a remarkable structure that measures approximately 300 km across. It was only recently observed in visible light from the ground with a telescope at the Pic du Midi Observatory in the Pyrenees (France) - this is the first infrared image to

  9. Laparoscopic repair of a lumbar hernia: report of a case and extensive review of the literature.

    PubMed

    Suarez, Sebastian; Hernandez, Juan D

    2013-09-01

    Lumbar hernias are a protrusion of intra-abdominal contents through a weakness or rupture in the posterior abdominal wall. They are considered to be a rare entity with approximately 300 cases reported in the literature since it was first described by Barbette in 1672. Petit described the inferior lumbar triangle in 1783 and Grynfeltt described the superior lumbar triangle in 1866; both are anatomical boundaries where 95% of lumbar hernias occur, whereas the other 5% are considered to be diffuse. Twenty percent of lumbar hernias are congenital and the other 80% are acquired; the acquired lumbar hernias can be further classified into either primary (spontaneous) or secondary. The typical presentation of lumbar hernias is a patient with a protruding semispherical bulge in the back with a slow growth. However, they may present with an incarcerated or strangulated bowel, so it is recommended that all lumbar hernias must be repaired as soon as they are diagnosed. The "gold standard" for diagnosing a lumbar hernia is a CT scan, because it is able to delineate muscular and fascial layers, detect a defect in one or more of these layers, evaluate the presence of herniated contents, differentiate muscle atrophy from a real hernia, and serve as a useful tool in the differential diagnosis, such as tumors. Recent studies have demonstrated the advantages of a laparoscopic repair instead of the classic open approach as the ideal treatment option for lumbar hernias. We report a case of a spontaneous lumbar hernia initially diagnosed as a lipoma and corrected with the open approach, but after relapsing 2 years later it was corrected using a laparoscopic approach. It is followed by an extensive review of lumbar hernias literature regarding history, anatomy, and surgical techniques.

  10. Black rings at large D

    NASA Astrophysics Data System (ADS)

    Tanabe, Kentaro

    2016-02-01

    We study the effective theory of slowly rotating black holes at the infinite limit of the spacetime dimension D. This large D effective theory is obtained by integrating the Einstein equation with respect to the radial direction. The effective theory gives equations for non-linear dynamical deformations of a slowly rotating black hole by effective equations. The effective equations contain the slowly rotating Myers-Perry black hole, slowly boosted black string, non-uniform black string and black ring as stationary solutions. We obtain the analytic solution of the black ring by solving effective equations. Furthermore, by perturbation analysis of effective equations, we find a quasinormal mode condition of the black ring in analytic way. As a result we confirm that thin black ring is unstable against non-axisymmetric perturbations. We also include 1 /D corrections to the effective equations and discuss the effects by 1 /D corrections.

  11. Perturbations of vortex ring pairs

    NASA Astrophysics Data System (ADS)

    Gubser, Steven S.; Horn, Bart; Parikh, Sarthak

    2016-02-01

    We study pairs of coaxial vortex rings starting from the action for a classical bosonic string in a three-form background. We complete earlier work on the phase diagram of classical orbits by explicitly considering the case where the circulations of the two vortex rings are equal and opposite. We then go on to study perturbations, focusing on cases where the relevant four-dimensional transfer matrix splits into two-dimensional blocks. When the circulations of the rings have the same sign, instabilities are mostly limited to wavelengths smaller than a dynamically generated length scale at which single-ring instabilities occur. When the circulations have the opposite sign, larger wavelength instabilities can occur.

  12. Radar Imaging of Saturn's Rings.

    NASA Astrophysics Data System (ADS)

    Nicholson, P. D.; Campbell, D. B.; French, R. G.; Margot, J.-L.; Black, G. J.; Nolan, M.

    2002-09-01

    The first radar echoes from Saturn's rings were obtained at a wavelength of 12.6 cm by Goldstein and Morris (1973). In October 1999 we used a frequency-stepped technique similar to that used in the mid-70s by Ostro etal. (1982) to make the first true radar images of the rings. In November 2000 and again in December 2001 we repeated this experiment, using the Arecibo S-band radar. With a pulse length of 70 msec, the range resolution of these data is 10,000 km; the Doppler spectra were processed to a frequency resolution of 2 kHz, corresponding to a radial resolution at the ring ansae of 2000 km. To date we have obtained images at ring opening angles B of -19.9, -23.6 and -25.9 deg. Images from all three years show a pronounced azimuthal asymmetry in the ring reflectivity, which is seen in both circular polarizations. The analogous phenomenon at visual wavelengths is ascribed to gravitational `wakes' generated by individual large ring particles, which are distorted by keplerian shear into elongated structures trailing at angles of 70 deg from the radial direction (Franklin and Colombo 1978). Such wakes are diagnostic of the rings' gravitational stability parameter, Q, and are expected to have characteristic length scales of 30-100 m in the A ring. To the radar, the rings appear brighter when the wakes are seen sideways, and fainter when they are viewed end-on. Fits of a numerical model by Salo and Karjalainen (1999) to our data show that the asymmetry is concentrated in the A ring, where its amplitude is 25% of the average reflectivity. This is twice the model prediction --- which is based on a dynamical simulation employing a realistic ring particle size distribution used as input to a Monte Carlo light scattering code --- and about three times the amplitude measured in HST images obtained at a wavelength of 439 nm and the same opening angle. The large amplitude of the radar asymmetry is difficult to reproduce with current models, although the phase of the asymmetry

  13. Detectability of pathological lesions in lumbar spine radiography

    NASA Astrophysics Data System (ADS)

    Tingberg, Anders; Bath, Magnus; Ruschin, Mark; Grahn, Anna; Besjakov, Jack; Borjesson, Sara; Hakansson, Markus; Mattsson, Soren; Mansson, Lars Gunnar

    2005-04-01

    Thirty images with added simulated pathological lesions at two different dose levels (100% and 10% dose) were evaluated with the free-response forced error experiment by nine experienced radiologists. The simulated pathological lesions present in the images were classified according to four different parameters: the position within the lumbar spine, possibility to perform a symmetrical (left-right) comparison, the lesion contrast, and the complexity of the surrounding background where the lesion was situated. The detectability of each lesion was calculated as the fraction of radiologists who successfully detected the lesion before a false positive error was made. The influence of each of the four parameters on lesion detectability was investigated. The results of the study show that the influence of lesion contrast is the most important factor for detectability. Since the dose level had a limited effect on detectability, large dose savings can be made without reducing the detectability of pathological lesions in lumbar spine radiography.

  14. Computer-aided diagnosis of lumbar stenosis conditions

    NASA Astrophysics Data System (ADS)

    Koompairojn, Soontharee; Hua, Kathleen; Hua, Kien A.; Srisomboon, Jintavaree

    2010-03-01

    Computer-aided diagnosis (CAD) systems are indispensable tools for patients' healthcare in modern medicine. Nevertheless, the only fully automatic CAD system available for lumbar stenosis today is for X-ray images. Its performance is limited due to the limitations intrinsic to X-ray images. In this paper, we present a system for magnetic resonance images. It employs a machine learning classification technique to automatically recognize lumbar spine components. Features can then be extracted from these spinal components. Finally, diagnosis is done by applying a Multilayer Perceptron. This classification framework can learn the features of different spinal conditions from the training images. The trained Perceptron can then be applied to diagnose new cases for various spinal conditions. Our experimental studies based on 62 subjects indicate that the proposed system is reliable and significantly better than our older system for X-ray images.

  15. [Histological changes of the lumbar ligamentum flavum with age].

    PubMed

    Kashiwagi, K

    1993-04-01

    The present author investigated morphometrically the changes associated with age in 137 ligamenta flava of the lumbar spine obtained from 79 patients with lumbar diseases and obtained the following results. The predominant changes were decrease of elastic fibers and increase of collagen fibers. The area of type II collagen fibers increased with age in the dorsal and central portions. Those were followed by proliferation of cartilage cells and calcification. The proliferation of cartilage cells was marked in the cranial and caudal insertion portions, and the layer of cartilage cells widened with age. Two types of calcification, deposition of calcium pyrophosphate dihydrate (CPPD) and deposition of hydroxyapatite (HAP), were observed. HAP deposits were small and frequently found in the dorsal portion, while CPPD deposits were larger and widely distributed.

  16. Chronic lumbar spine and radicular pain: pathophysiology and treatment.

    PubMed

    Wheeler, Anthony H; Murrey, Daniel B

    2002-04-01

    The lumbar spine forms the foundation and infrastructure of an organic skyscraper equipped with the physiologic capacity to act as a crane for lifting and a crankshaft for walking. Subjected to aging like other "human machinery," the lumbar spine adapts to the wear and tear of gravity and biomechanical loading through structural and neurochemical changes. Many of the changes are maladaptive, resulting in pain, physical and functional disability, and altered neurophysiologic circuitry. Some compensatory reactions are constructive, but others cause more interference with the organism's capacity to cope. A conceptional understanding of the multifaceted structural, biomechanical, biochemical, medical, and psychosocial influences that compose this mix elucidates the complexity of applying effective treatments. PMID:11872180

  17. Lumbar spinal angiolipoma: case report and review of the literature.

    PubMed

    Konya, Deniz; Ozgen, Serdar; Kurtkaya, Ozlem; Pamir, Necmettin M

    2006-06-01

    Spinal angiolipomas are extremely rare benign tumors composed of mature lipomatous and angiomatous elements. Most are symptomatic due to progressive spinal cord or root compression. This article describes the case of a 60-year-old woman who presented with a 6-month history of low back pain radiating to her right leg. The pain was multisegmental. The condition had worsened with time. Lumbar magnetic resonance imaging revealed a dorsal epidural mass at L5 and erosion of the lamina of the L5 vertebra. Laminectomy was performed, and an extradural tumor was totally excised. Neuropathologic examination identified it as a lumbar spinal angiolipoma. There was no evidence of recurrence in follow-up 12 months later. This rare clinical entity must be considered in the differential diagnosis for any spinal epidural lesion.

  18. Herniated Lumbar Disc Combined with Spinal Intradural Extramedullary Cysticercosis

    PubMed Central

    Choi, Kyeong Bo; Choi, Won Gyu; Lee, Sang-Ho

    2010-01-01

    Spinal cysticercosis is a very uncommon manifestation of neurocysticercosis which is caused by the larvae of Taenia solium. However, it can develop as a primary infection through blood stream or direct larval migration. It can result in high recurrence and severe neurologic morbidity if not treated appropriately. We report the case of a 43-year-old woman who presented with severe lower back pain and left leg radiating pain in recent 2 weeks. Magnetic resonance image (MRI) of lumbar spine demonstrated extruded disc at the L5-S1 level combined with intradural extramedullary cystic lesion. We performed the open lumbar microdiscectomy (OLM) at L5-S1 on the left with total excision of cystic mass. After surgery, the patient showed an improvement of previous symptoms. Diagnosis was confirmed by histopathological examination as intradural extramedullary cysticercosis. We discuss clinical features, diagnostic screening, and treatment options of spinal cysticercosis. PMID:21430986

  19. Early adolescent lumbar intervertebral disc injury: a case study

    PubMed Central

    2013-01-01

    This article describes and discusses the case of an adolescent male with lumbar intervertebral disc injury characterized by chronic low back pain (LBP) and antalgia. A 13-year-old boy presented for care with a complaint of chronic LBP and subsequent loss of quality of life. The patient was examined and diagnosed by means of history, clinical testing and use of imaging. He had showed failure in natural history and conservative management relief in both symptomatic and functional improvement, due to injury to the intervertebral joints of his lower lumbar spine. Discogenic LBP in the young adolescent population must be considered, particularly in cases involving even trivial minor trauma, and in those in which LBP becomes chronic. More research is needed regarding long-term implications of such disc injuries in young people, and how to best conservatively manage these patients. A discussion of discogenic LBP pertaining to adolescent disc injury is included. PMID:23621900

  20. Lumbar Spinal Stenosis: Who Should Be Fused? An Updated Review

    PubMed Central

    Hasankhani, Ebrahim Ghayem; Ashjazadeh, Amir

    2014-01-01

    Lumbar spinal stenosis (LSS) is mostly caused by osteoarthritis (spondylosis). Clinically, the symptoms of patients with LSS can be categorized into two groups; regional (low back pain, stiffness, and so on) or radicular (spinal stenosis mainly presenting as neurogenic claudication). Both of these symptoms usually improve with appropriate conservative treatment, but in refractory cases, surgical intervention is occasionally indicated. In the patients who primarily complain of radiculopathy with an underlying biomechanically stable spine, a decompression surgery alone using a less invasive technique may be sufficient. Preoperatively, with the presence of indicators such as failed back surgery syndrome (revision surgery), degenerative instability, considerable essential deformity, symptomatic spondylolysis, refractory degenerative disc disease, and adjacent segment disease, lumbar fusion is probably recommended. Intraoperatively, in cases with extensive decompression associated with a wide disc space or insufficient bone stock, fusion is preferred. Instrumentation improves the fusion rate, but it is not necessarily associated with improved recovery rate and better functional outcome. PMID:25187873

  1. PRIMARY LIPOSARCOMA OF THE LUMBAR SPINE: CASE REPORT

    PubMed Central

    de Moraes, Frederico Barra; Cardoso, André Luiz Passos; Tristão, Newton Antônio; Pimenta, Wilson Eloy; Daher, Sérgio; de Souza Carneiro, Siderley; Barbosa, Nathalia Parrode Machado; de Lima Malta, Nayanne; Ribeiro, Noara Barros

    2015-01-01

    We report a rare case of primary bone liposarcoma of the lumbar spine, for which only one case has been reported. A female patient, 60 years of age, with lumbar pain and left sciatalgy for six months. In the imaging exams, a destructive tumor was found in the L4 vertebral body, and magnetic resonance imaging (MRI) revealed a tumoral lesion with T1 hiposignal and T2 hypersignal. Histological diagnosis was difficult, and immunohistochemistry confirmed the diagnosis. Surgical treatment was performed with wide ressection, spinal cord decompression, and anterior and posterior fusion of L3 to L5 complemented by radiotherapy and chemotherapy. After three years, a computed tomography (CT) scan evidenced an expansive injury in the lung. Despite its rarity, liposarcoma should be considered in the differential diagnosis of sciatica and primary tumors of the spine. PMID:27027092

  2. [Influence of the weather on the course of lumbar syndromes].

    PubMed

    Machalek, A; Tilscher, H; Friedrich, M; Polt, E

    1980-01-01

    Sensation of pain during lumbar syndromes is correlated with weather situations, the definition of which takes into consideration traditional as well as new methods of weather classification. To this end, it was necessary to develop an algesia index for the purpose of defining the subjective pain sensation by classifying it in different groups enabling the application of medico-meteorological statistics. The medical data were correlated with the following meteorological arametes: Weather-phase scheme according to Brezowsky-Ungeheuer; temperature-humidity environment; weather situations for Central Europe; synoptic index cycle; advention of temperature in medium altitudes of the atmosphere; vorticity for cyclogenesis. The following results were obtained: Pain sensation in the lumbar area shows a significant dependence on weather situations. Althoguh singular meteorological parameters are not important, the human body is affected primarily by the sum total of all weather elements. PMID:6447957

  3. Ring resonant cavities for spectroscopy

    DOEpatents

    Zare, Richard N.; Martin, Juergen; Paldus, Barbara A.; Xie, Jinchun

    1999-01-01

    Ring-shaped resonant cavities for spectroscopy allow a reduction in optical feedback to the light source, and provide information on the interaction of both s- and p-polarized light with samples. A laser light source is locked to a single cavity mode. An intracavity acousto-optic modulator may be used to couple light into the cavity. The cavity geometry is particularly useful for Cavity Ring-Down Spectroscopy (CRDS).

  4. MUON STORAGE RINGS - NEUTRINO FACTORIES

    SciTech Connect

    PARSA,Z.

    2000-05-30

    The concept of a muon storage ring based Neutrino Source (Neutrino Factory) has sparked considerable interest in the High Energy Physics community. Besides providing a first phase of a muon collider facility, it would generate more intense and well collimated neutrino beams than currently available. The BNL-AGS or some other proton driver would provide an intense proton beam that hits a target, produces pions that decay into muons. The muons must be cooled, accelerated and injected into a storage ring with a long straight section where they decay. The decays occurring in the straight sections of the ring would generate neutrino beams that could be directed to detectors located thousands of kilometers away, allowing studies of neutrino oscillations with precisions not currently accessible. For example, with the neutrino source at BNL, detectors at Soudan, Minnesota (1,715 km), and Gran Sasso, Italy (6,527 km) become very interesting possibilities. The feasibility of constructing and operating such a muon-storage-ring based Neutrino-Factory, including geotechnical questions related to building non-planar storage rings (e.g. at 8{degree} angle for BNL-Soudan, and 3{degree} angle for BNL-Gran Sasso) along with the design of the muon capture, cooling, acceleration, and storage ring for such a facility is being explored by the growing Neutrino Factory and Muon Collider Collaboration (NFMCC). The authors present overview of Neutrino Factory concept based on a muon storage ring, its components, physics opportunities, possible upgrade to a full muon collider, latest simulations of front-end, and a new bowtie-muon storage ring design.

  5. Ring resonant cavities for spectroscopy

    DOEpatents

    Zare, R.N.; Martin, J.; Paldus, B.A.; Xie, J.

    1999-06-15

    Ring-shaped resonant cavities for spectroscopy allow a reduction in optical feedback to the light source, and provide information on the interaction of both s- and p-polarized light with samples. A laser light source is locked to a single cavity mode. An intracavity acousto-optic modulator may be used to couple light into the cavity. The cavity geometry is particularly useful for Cavity Ring-Down Spectroscopy (CRDS). 6 figs.

  6. Resonance capture and Saturn's rings

    SciTech Connect

    Patterson, C.W.

    1986-05-01

    We have assigned the resonances apparently responsible for the stabilization of the Saturn's shepherd satellites and for the substructure seen in the F-ring and the ringlets in the C-ring. We show that Saturn's narrow ringlets have a substructure determined by three-body resonances with Saturn's ringmoons and the sun. We believe such resonances have important implications to satellite formation. 17 refs., 1 fig., 1 tab.

  7. Collector ring project at FAIR

    NASA Astrophysics Data System (ADS)

    Dolinskii, A.; Berkaev, D.; Blell, U.; Dimopoulou, C.; Gorda, O.; Leibrock, H.; Litvinov, S.; Laier, U.; Koop, I.; Schurig, I.; Starostenko, A.; Shatunov, P.; Weinrich, U.

    2015-11-01

    The collector ring is a dedicated ring for fast cooling of ions coming from separators at the FAIR project. To accommodate optimal technical solutions, a structure of a magnet lattice was recently reviewed and modified. Consequently, more appropriate technical solutions for the main magnets could be adopted. A general layout and design of the present machine is shown. The demanding extraction schemes have been detailed and open design issues were completed.

  8. Density waves in Saturn's rings

    NASA Astrophysics Data System (ADS)

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

    1981-08-01

    Certain radial brightness variations in the outer Cassini division of Saturn's rings may be spiral density waves driven by Saturn's large moon Iapetus, in which case a value of approximately 16 g/sq cm for the surface density is calculated in the region where the waves are seen. The kinematic viscosity in the same region is approximately 170 sq cm/s and the vertical scale height of the ring is estimated to be a maximum of approximately 40 m.

  9. Compound fiber ring resonator: Theory

    SciTech Connect

    Zhang, J.; Lit, J.W.Y.

    1994-06-01

    A compound fiber ring resonator is made with a Fabry-Perot etalon built inside a fiber ring that is fed through a 2 x 2 directional single-mode fiber coupler. It is theoretically analyzed by an unfolded equivalent model and a transfer-matrix method. The output intensities are presented, and four cases are discussed. The results may be useful in applications such as fiber spectrum analyzers, sensors, and lasers. 25 refs., 9 figs.

  10. Analysis of Efficacy Differences between Caudal and Lumbar Interlaminar Epidural Injections in Chronic Lumbar Axial Discogenic Pain: Local Anesthetic Alone vs. Local Combined with Steroids

    PubMed Central

    Manchikanti, Laxmaiah; Pampati, Vidyasagar; Benyamin, Ramsin M.; Boswell, Mark V.

    2015-01-01

    Study Design: Comparative assessment of randomized controlled trials of caudal and lumbar interlaminar epidural injections in chronic lumbar discogenic pain. Objective: To assess the comparative efficacy of caudal and lumbar interlaminar approaches of epidural injections in managing axial or discogenic low back pain. Summary of Background Data: Epidural injections are commonly performed utilizing either a caudal or lumbar interlaminar approach to treat chronic lumbar axial or discogenic pain, which is pain exclusive of that associated with a herniated intervertebral disc, or that is due to degeneration of the zygapophyseal joints, or due to dysfunction of the sacroiliac joints, respectively. The literature on the efficacy of epidural injections in managing chronic axial lumbar pain of presumed discogenic origin is limited. Methods: The present analysis is based on 2 randomized controlled trials of chronic axial low back pain not caused by disc herniation, radiculitis, or facet joint pain, utilizing either a caudal or lumbar interlaminar approach, with a total of 240 patients studied, and a 24-month follow-up. Patients were assigned to receive either local anesthetic only or local anesthetic with a steroid in each 60 patient group. Results: The primary outcome measure was significant improvement, defined as pain relief and functional status improvement of at least 50% from baseline, which was reported at 24-month follow-ups in 72% who received local anesthetic only with a lumbar interlaminar approach and 54% who received local anesthetic only with a caudal approach. In patients receiving local anesthetic with a steroid, the response rate was 67% for those who had a lumbar interlaminar approach and 68% for those who had a caudal approach at 12 months. The response was significantly better in the lumbar interlaminar group who received local anesthetic only, 77% versus 56% at 12 months and 72% versus 54% at 24 months. Conclusion: This assessment shows that in patients

  11. An integrated model of ring pack performance

    NASA Technical Reports Server (NTRS)

    Keribar, R.; Dursunkaya, Z.; Flemming, M. F.

    1991-01-01

    This paper describes an integrated model developed for the detailed characterization and simulation of piston ring pack behavior in internal combustion engines and the prediction of ring pack performance. The model includes comprehensive and coupled treatments of (1) ring-liner hydrodynamic and boundary lubrication and friction; (2) ring axial, radial, and (toroidal) twist dynamics; (3) inter-ring gas dynamics and blowby. The physics of each of these highly inter-related phenomena are represented by submodels, which are intimately coupled to form a design-oriented predictive tool aimed at the calculation of ring film thicknesses, ring motions, land pressures, engine friction, and blowby. The paper also describes the results of a series of analytical studies investigating effects of engine speed and load and ring pack design parameters, on ring motions, film thicknesses, and inter-ring pressures, as well as ring friction and blowby.

  12. Treatment of lumbar disc herniation by percutaneous laser disc decompression (PLDD) and modified PLDD

    NASA Astrophysics Data System (ADS)

    Chi, Xiao fei; Li, Hong zhi; Wu, Ru zhou; Sui, Yun xian

    2005-07-01

    Objective: To study the micro-invasive operative method and to compare the effect of treatment of PLDD and modified PLDD for Lumbar Disc Herniation. Method: Vaporized part of the nucleus pulposus in single or multiple point after acupuncture into lumbar disc, to reach the purpose of the decompression of the lumbar disc. Result: Among the 19 cases of the regular PLDD group, the excellent and good rate was 63.2%, and among the 40 cases of the modified PLDD group, the excellent and good rate was 82.5%. Conclusion: The modified PLDD has good effect on the treatment for lumbar disc herniation.

  13. Decreasing the required lumbar extensor moment induces earlier onset of flexion relaxation.

    PubMed

    Zwambag, Derek P; De Carvalho, Diana E; Brown, Stephen H M

    2016-10-01

    Flexion relaxation (FR) is characterized by the lumbar erector spinae (LES) becoming myoelectrically silent near full trunk flexion. This study was designed to: (1) determine if decreasing the lumbar moment during flexion would induce FR to occur earlier; (2) characterize thoracic and abdominal muscle activity during FR. Ten male participants performed four trunk flexion/extension movement conditions; lumbar moment was altered by attaching 0, 5, 10, or 15lb counterweights to the torso. Electromyography (EMG) was recorded from eight trunk muscles. Lumbar moment, lumbar flexion and trunk inclination angles were calculated at the critical point of LES inactivation (CPLES). Results demonstrated that counterweights decreased the lumbar moment and lumbar flexion angle at CPLES (p<0.0001 and p=0.0029, respectively); the hypothesis that FR occurs earlier when lumbar moment is reduced was accepted. The counterweights did not alter trunk inclination at CPLES (p=0.1987); this is believed to result from an altered hip to spine flexion ratio when counterweights were attached. Lumbar multifidus demonstrated FR, similar to LES, while thoracic muscles remained active throughout flexion. Abdominal muscles activated at the same instant as CPLES, except in the 15lb condition where abdominal muscles activated before CPLES resulting in a period of increased co-contraction. PMID:27267174

  14. The radiological diagnosis of spinal stenosis in the lumbar canal.

    PubMed

    Urso, S; Pacciani, E; Donnetti, L

    1986-03-01

    Based on a study of 132 patients suffering from lumbar spinal stenosis, the authors propose a simple classification aimed at providing the surgeon with the maximum essential information on which to plan surgery. This is based on an analysis of standard radiographic and radiculographic findings, and stresses the importance of diagnosing the correct type and level of the stenosis. Certain physiopathological aspects of the subarachnoid space which have a bearing on the use of contrast radiography are also discussed. PMID:3733427

  15. Lift performance and lumbar loading in standing and seated lifts.

    PubMed

    Middleton, Kane J; Carstairs, Greg L; Ham, Daniel J

    2016-09-01

    This study investigated the effect of posture on lifting performance. Twenty-three male soldiers lifted a loaded box onto a platform in standing and seated postures to determine their maximum lift capacity and maximum acceptable lift. Lift performance, trunk kinematics, lumbar loads, anthropometric and strength data were recorded. There was a significant main effect for lift effort but not for posture or the interaction. Effect sizes showed that lumbar compression forces did not differ between postures at lift initiation (Standing 5566.2 ± 627.8 N; Seated 5584.0 ± 16.0) but were higher in the standing posture (4045.7 ± 408.3 N) when compared with the seated posture (3655.8 ± 225.7 N) at lift completion. Anterior shear forces were higher in the standing posture at both lift initiation (Standing 519.4 ± 104.4 N; Seated 224.2 ± 9.4 N) and completion (Standing 183.3 ± 62.5 N; Seated 71.0 ± 24.2 N) and may have been a result of increased trunk flexion and a larger horizontal distance of the mass from the L5-S1 joint. Practitioner Summary: Differences between lift performance and lumbar forces in standing and seated lifts are unclear. Using a with-in subjects repeated measures design, we found no difference in lifted mass or lumbar compression force at lift initiation between standing and seated lifts.

  16. Is epidural steroid injection effective for degenerative lumbar spinal stenosis?

    PubMed

    Flores, Sebastián; Molina, Marcelo

    2015-11-16

    There are several nonsurgical alternatives to treat radicular pain in degenerative lumbar spinal stenosis. Epidural steroid injections have been used for several decades, but the different studies have shown variable effects. Searching in Epistemonikos database, which is maintained by screening 30 databases, we identified nine systematic reviews including seven pertinent randomized controlled trials. We concluded epidural steroid injection probably leads to little or no effect on reducing radicular pain of spinal stenosis.

  17. Is epidural steroid injection effective for degenerative lumbar spinal stenosis?

    PubMed

    Flores, Sebastián; Molina, Marcelo

    2015-01-01

    There are several nonsurgical alternatives to treat radicular pain in degenerative lumbar spinal stenosis. Epidural steroid injections have been used for several decades, but the different studies have shown variable effects. Searching in Epistemonikos database, which is maintained by screening 30 databases, we identified nine systematic reviews including seven pertinent randomized controlled trials. We concluded epidural steroid injection probably leads to little or no effect on reducing radicular pain of spinal stenosis. PMID:26610278

  18. Lumbar artery branch injury secondary to ureteroscopic manipulation

    PubMed Central

    Rothberg, Michael B.; Monga, Manoj; Gupta, Mantu

    2014-01-01

    Iatrogenic vascular injury in ureteroscopy is relatively uncommon and typically presents as a subcapsular hematoma. We report the case of an injury to a branch of the lumbar artery secondary to ureteral trauma during ureteroscopy. In the immediate postoperative period, the patient became hypotensive and tachycardic, prompting a workup that revealed an active hemorrhage. The patient then underwent subsequent angiogram and successful coil embolization. PMID:25024804

  19. Collar nut and thrust ring

    DOEpatents

    Lowery, Guy B.

    1991-01-01

    A collar nut comprises a hollow cylinder having fine interior threads at one end for threadably engaging a pump mechanical seal assembly and an inwardly depending flange at the other end. The flange has an enlarged portion with a groove for receiving an O-ring for sealing against the intrusion of pumpage from the exterior. The enlarged portion engages a thrust ring about the pump shaft for crushing a hard O-ring, such as a graphite O-ring. The hard O-ring seals the interior of the mechanical seal assembly and pump housing against the loss of lubricants or leakage of pumpage. The fine threads of the hollow cylinder provide the mechanical advantage for crushing the hard O-ring evenly and easily with a hand tool from the side of the collar nut rather than by tightening a plurality of bolts from the end and streamlines the exterior surface of the mechanical seal. The collar nut avoids the spatial requirements of bolt heads at the end of a seal and associated bolt head turbulence.

  20. Physics of Jupiter's Gossamer Rings

    NASA Astrophysics Data System (ADS)

    Hamilton, Douglas P.; Krueger, H.

    2007-10-01

    Thebe's gossamer ring, the outermost and faintest of Jupiter's rings, has an outward extension that we have previously argued is due to a shadow resonance (Hamilton 2003, DPS meeting #35, #11.09). A shadow resonance arises from the abrupt shutoff of photoelectric charging when a dust particle enters Jupiter's shadow which, in turn, affects the strength of the electromagnetic perturbation from the planet's intense magnetic field. The result is a coupled oscillation between a particle's orbital eccentricity and its semimajor axis. Ring material spreads outward from Thebe while maintaining its vertical thickness just as observed by Galileo imaging. In addition to cameras, the Galileo spacecraft was also equipped with dust and plasma detectors. The spacecraft made two passes through the ring and its dust detector found that 1) dust fluxes drop immediately interior to Thebe's orbit, 2) some grains have inclinations in excess of 20 degrees and 3) submicron particles are present in the Amalthea ring in much greater numbers than in the Thebe ring. These findings can all be explained in the context of our shadow resonance model: the inner boundary is a direct consequence of the conservation of the Electromagnetic Jacobi Constant, the high inclinations are forced by a vertical resonance, and the excess submicron particles are a consequence of the weakening of electromagnetic forces in the vicinity of synchronous orbit. In this talk, we will present the data sets as well as detailed numerical simulations that back up these claims.

  1. First Evidence of Jupiter Ring

    NASA Technical Reports Server (NTRS)

    1979-01-01

    First evidence of a ring around the planet Jupiter is seen in this photograph taken by Voyager 1 on March 4, 1979. The multiple exposure of the extremely thin faint ring appears as a broad light band crossing the center of the picture. The edge of the ring is 1,212,000 km from the spacecraft and 57,000 km from the visible cloud deck of Jupiter. The background stars look like broken hair pins because of spacecraft motion during the 11 minute 12 second exposure. The wavy motion of the star trails is due to the ultra-slow natural oscillation of the spacecraft (with a period of 78 seconds). The black dots are geometric calibration points in the camera. The ring thickness is estimated to be 30 km or less. The photograph was part of a sequence planned to search for such rings in Jupiter's equatorial plane. The ring has been invisible from Earth because of its thinness and its transparency when viewed at any angle except straight on. JPL manages and controls the Voyager Project for NASA's Office of Space Science.

  2. Of Rings and Volcanoes

    NASA Astrophysics Data System (ADS)

    2002-01-01

    Office National d'Etudes et de Recherches Aérospatiales (ONERA) , Laboratoire d'Astrophysique de Grenoble (LAOG) and the DESPA and DASGAL laboratories of the Observatoire de Paris in France, in collaboration with ESO. The CONICA infra-red camera was built, under an ESO contract, by the Max-Planck-Institut für Astronomie (MPIA) (Heidelberg) and the Max-Planck Institut für Extraterrestrische Physik (MPE) (Garching) in Germany, in collaboration with ESO. Saturn - Lord of the rings ESO PR Photo 04a/02 ESO PR Photo 04a/02 [Preview - JPEG: 460 x 400 pix - 54k] [Normal - JPEG: 1034 x 800 pix - 200k] Caption : PR Photo 04a/02 shows the giant planet Saturn, as observed with the VLT NAOS-CONICA Adaptive Optics instrument on December 8, 2001; the distance was 1209 million km. It is a composite of exposures in two near-infrared wavebands (H and K) and displays well the intricate, banded structure of the planetary atmosphere and the rings. Note also the dark spot at the south pole at the bottom of the image. One of the moons, Tethys, is visible as a small point of light below the planet. It was used to guide the telescope and to perform the adaptive optics "refocussing" for this observation. More details in the text. Technical information about this photo is available below. This NAOS/CONICA image of Saturn ( PR Photo 04a/02 ), the second-largest planet in the solar system, was obtained at a time when Saturn was close to summer solstice in the southern hemisphere. At this moment, the tilt of the rings was about as large as it can be, allowing the best possible view of the planet's South Pole. That area was on Saturn's night side in 1982 and could therefore not be photographed during the Voyager encounter. The dark spot close to the South Pole is a remarkable structure that measures approximately 300 km across. It was only recently observed in visible light from the ground with a telescope at the Pic du Midi Observatory in the Pyrenees (France) - this is the first infrared image to

  3. Lumbar cisternography in evaluation of hydrocephalus in the preterm infant

    SciTech Connect

    Donn, S.M.; Roloff, D.W.; Keyes, J.W. Jr.

    1983-10-01

    Radionuclide lumbar cisternography using indium 111-diethylenetriamine pentaacetic acid (111In-DTPA) and a mobile gamma-camera with a converging collimator was utilized as a bedside procedure to evaluate CSF dynamics and the patency of the cerebral ventricular system in 30 preterm infants with hydrocephalus. Serial images of the brain were obtained at 0, 1, 2, 6, 24, and 48 hours after instillation of the isotope in the lumbar subarachnoid space. Three distinct patterns were seen. Infants with posthemorrhagic hydrocephalus displayed prompt ventricular filling but markedly delayed emptying with minimal flow over the cerebral convexities. Infants with ventriculomegaly secondary to suspected brain atrophy or periventricular leukomalacia demonstrated a pattern of prompt ventricular filling, delayed emptying, but with flow present over the convexities. An infant with noncommunicating hydrocephalus secondary to an Arnold-Chiari malformation showed a pattern of complete obstruction with no ventricular filling. Radionuclide lumbar cisternography appears to be a safe, well-tolerated procedure which produces images of sufficient resolution to provide valuable information about CSF dynamics, delineating basal cisternae, ventricles, and subarachnoid flow paths.

  4. Percutaneous cryodenervation of lumbar facet joints: a prospective clinical trial

    PubMed Central

    Veihelmann, A.; Trouillier, H.; Hausdorf, J.; Devens, C.; Wegener, B.; Jansson, V.; von Schulze Pellengahr, C.

    2006-01-01

    Facet joint pain is an important aspect of degenerative lumbar spine disease, and radiofrequency medial branch neurotomy remains an established therapy, while cryodenervation has still been poorly examined. This study was undertaken to examine the effects of medial branch cryodenervation in the treatment of lumbar facet joint pain. This was a prospective clinical case series. Patient selection was based on the history, physical examination and positive medial branch blocks. Percutaneous medial branch cryodenervation was performed using a Lloyd Neurostat 2000. Target parameters were low back pain (VAS), limitation of activity (McNab) and overall satisfaction. Fifty patients were recruited, and 46 completed the study. The follow-up time was 1 year. At 6 weeks, 33 patients (72%) were pain free or had major improvement of low back pain; 13 (28%) had no or little improvement. Including failures, mean low back pain decreased significantly from 7.7 preoperatively to 3.2 at 6 weeks, 3.3 at 3 months, 3.0 at 6 months and 4.2 at 12 months (P<0.0001). Limitation of the activities of daily living improved parallel to reduced pain. Our results suggest that medial branch cryodenervation is a safe and effective treatment for lumbar facet joint pain. PMID:16927087

  5. Automatic determination of the imaging plane in lumbar MRI

    NASA Astrophysics Data System (ADS)

    Masaki, Tsurumaki; Lee, Yongbum; Tsai, Du-Yih; Sekiya, Masaru; Kazama, Kiyoko

    2006-03-01

    In this paper we describe a method for assisting radiological technologists in their routine work to automatically determine the imaging plane in lumbar MRI. The method is first to recognize the spinal cord and the intervertebral disk (ID) from the lumbar vertebra 3-plane localizer image, and then the imaging plane is automatically determined according to the recognition results. To determine the imaging plane, the spinal cord and the ID are automatically recognized from the lumbar vertebra 3-plane localizer image with a series of image processing techniques. The proposed method consists of three major steps. First, after removing the air and fat regions from the 3-plane localizer image by use of histogram analysis, the rachis region is specified with Sobel edge detection filter. Second, the spinal cord and the ID were respectively extracted from the specified rachis region making use of global thresholding and the line detection filter. Finally, the imaging plane is determined by finding the straight line between the spinal cord and the ID with the Hough transform. Image data of 10 healthy volunteers were used for investigation. To validate the usefulness of our proposed method, manual determination of the imaging plane was also conducted by five experienced radiological technologists. Our experimental results showed that the concordance rate between the manual setting and automatic determination reached to 90%. Moreover, a remarkable reduction in execution time for imaging-plane determination was also achieved.

  6. Angiogenesis in the degeneration of the lumbar intervertebral disc

    PubMed Central

    David, Gh; Iencean, SM; Mohan, A

    2010-01-01

    The goal of the study is to show the histological and biochemical changes that indicate the angiogenesis of the intervertebral disc in lumbar intervertebral disc hernia and the existence of epidemiological correlations between these changes and the risk factors of lumbar intervertebral disc hernia, as well as the patient's quality of life (QOL). We have studied 50 patients aged between 18 and 73 years old, who have undergone lumbar intervertebral disc hernia surgery, making fibroblast growth factor and vascular endothelial growth factor level measurements, as elements in the process of appreciating the disc angiogenesis. Also, pre–surgery and post–surgery QOL has been measured, as well as the intensity of the pain syndrome. We have identified factors capable of stimulating vascular endothelial growth (VEGF, FGF–2) for the examined disc material, but histological examination did not show angiogenesis. The process of angiogenesis at the degenerated intervertebral disc level affects the patient's quality of life both pre and postoperatively, and may be a predictive factor for the post–operative results. Patients can prevent the appearance of angiogenesis type degenerative processes of the intervertebral disc by avoiding angiogenesis correlated factors (weight control, physical effort, and smoking). PMID:20968201

  7. Comparison of the different surgical approaches for lumbar interbody fusion.

    PubMed

    Talia, Adrian J; Wong, Michael L; Lau, Hui C; Kaye, Andrew H

    2015-02-01

    This review will outline the history of spinal fusion. It will compare the different approaches currently in use for interbody fusion. A comparison of the techniques, including minimally invasive surgery and graft options will be included. Lumbar interbody fusion is a commonly performed surgical procedure for a variety of spinal disorders, especially degenerative disease. Currently this procedure is performed using anterior, lateral, transforaminal and posterior approaches. Minimally invasive techniques have been increasing in popularity in recent years. A posterior approach is frequently used and has good fusion rates and low complication rates but is limited by the thecal and nerve root retraction. The transforaminal interbody fusion avoids some of these complications and is therefore preferable in some situations, especially revision surgery. An anterior approach avoids the spinal cord and cauda equina all together, but has issues with visceral exposure complications. Lateral lumbar interbody fusion has a risk of lumbar plexus injury with dissection through the psoas muscle. Studies show less intraoperative blood loss for minimally invasive techniques, but there is no long-term data. Iliac crest is the gold standard for bone graft, although adjuncts such as bone morphogenetic proteins are being used more frequently, despite their controversial history. More high-level studies are needed to make generalisations regarding the outcomes of one technique compared with another.

  8. Access related complications during anterior exposure of the lumbar spine

    PubMed Central

    Fantini, Gary A; Pawar, Abhijit Y

    2013-01-01

    The new millennium has witnessed the emergence of minimally invasive, non-posterior based surgery of the lumbar spine, in particular via lateral based methodologies to discectomy and fusion. In contrast, and perhaps for a variety of reasons, anterior motion preservation (non-fusion) technologies are playing a comparatively lesser, though incompletely defined, role at present. Lateral based motion preservation technologies await definition of their eventual role in the armamentarium of minimally invasive surgical therapies of the lumbar spine. While injury to the major vascular structures remains the most serious and feared complication of the anterior approach, this occurrence has been nearly eliminated by the use of lateral based approaches for discectomy and fusion cephalad to L5-S1. Whether anterior or lateral based, non-posterior approaches to the lumbar spine share certain access related pitfalls and complications, including damage to the urologic and neurologic structures, as well as gastrointestinal and abdominal wall issues. This review will focus on the recognition, management and prevention of these anterior and lateral access related complications. PMID:23362471

  9. Patient positioning and spinal locking for lumbar spine rotation manipulation.

    PubMed

    Gibbons, P; Tehan, P

    2001-08-01

    High velocity low amplitude (HVLA) thrust techniques are widely used by many manual therapists to treat low back pain. There is increasing evidence that spinal manipulation produces positive patient outcomes for acute low back pain. HVLA thrust techniques are associated with an audible release in the form of a pop or cracking sound that is widely accepted to represent cavitation of a spinal zygapophyseal joint. This audible release distinguishes these techniques from other manual therapy interventions. When using long lever HVLA thrust techniques spinal locking is necessary to localize forces and achieve cavitation at a specific vertebral segment. A critical factor in applying lumbar spine manipulation with minimal force is patient positioning and spinal locking. A knowledge of coupled movements of the lumbar spine aids an understanding of the patient positioning required to achieve spinal locking consistent with maximal patient comfort and cooperation. Excessive rotation can result in pain, patient resistance and failed technique. This masterclass presents a model of patient positioning for the lumbar spine that minimizes excessive use of rotation to achieve spinal locking prior to the application of the thrust.

  10. [Ultrasonography-guided identification of the lumbar epidural space].

    PubMed

    Bonazzi, M; Bianchi De Grazia, L; Di Gennaro, S; Lensi, C; Migliavacca, S; Marsicano, M; Riva, A; Laveneziana, D

    1995-05-01

    The study was designed to assess the reliability of sonographic evaluation in the prediction of the depth of the lumbar epidural space. Forty males, scheduled for epidural anesthesia for surgical repair of inguinal hernia, were prospectively studied. Patients were placed in a sitting position and sagittal scanning of the lumbar spine was performed with a 5-MHz transducer over the fourth or fifth interspace in order to identify the deeper hyperechogen interface, which represents the landmark between the ligamentum flavum and the epidural space. Ultrasound depth was measured and transducer removed. A Tuohy needle 18 G was then introduced percutaneously according to the standard technique and a rubber slide placed over it, so that it depth of insertion could be accurately measured. The potential for using ultrasounds for prediction of the distance from skin to epidural space was analyzed using a simple linear regression analysis; p values < 0.05 were considered significant. Mean values of ultrasound depth and needle depth were respectively 51 mm (SD 6.3) and 50.9 mm (SD 6.2); the correlation coefficient was 0.99. Ultrasound scanning of the lumbar spine provides an accurate measurement of the depth of the epidural space, which can facilitate the performance of the epidural anaesthesia and may decrease the complication rate, particularly in those patients in which anatomic landmarks are obscured.

  11. Flexible Stabilisation of the Degenerative Lumbar Spine Using PEEK Rods.

    PubMed

    Benezech, Jacques; Garlenq, Bruno; Larroque, Gilles

    2016-01-01

    Posterior lumbar interbody fusion using cages, titanium rods, and pedicle screws is considered today as the gold standard of surgical treatment of lumbar degenerative disease and has produced satisfying long-term fusion rates. However this rigid material could change the physiological distribution of load at the instrumental and adjacent segments, a main cause of implant failure and adjacent segment disease, responsible for a high rate of further surgery in the following years. More recently, semirigid instrumentation systems using rods made of polyetheretherketone (PEEK) have been introduced. This clinical study of 21 patients focuses on the clinical and radiological outcomes of patients with lumbar degenerative disease treated with Initial VEOS PEEK(®)-Optima system (Innov'Spine, France) composed of rods made from PEEK-OPTIMA(®) polymer (Invibio Biomaterial Solutions, UK) without arthrodesis. With an average follow-up of 2 years and half, the chances of reoperation were significantly reduced (4.8%), quality of life was improved (ODI = 16%), and the adjacent disc was preserved in more than 70% of cases. Based on these results, combined with the biomechanical and clinical data already published, PEEK rods systems can be considered as a safe and effective alternative solution to rigid ones. PMID:26981285

  12. Flexible Stabilisation of the Degenerative Lumbar Spine Using PEEK Rods

    PubMed Central

    Benezech, Jacques; Garlenq, Bruno; Larroque, Gilles

    2016-01-01

    Posterior lumbar interbody fusion using cages, titanium rods, and pedicle screws is considered today as the gold standard of surgical treatment of lumbar degenerative disease and has produced satisfying long-term fusion rates. However this rigid material could change the physiological distribution of load at the instrumental and adjacent segments, a main cause of implant failure and adjacent segment disease, responsible for a high rate of further surgery in the following years. More recently, semirigid instrumentation systems using rods made of polyetheretherketone (PEEK) have been introduced. This clinical study of 21 patients focuses on the clinical and radiological outcomes of patients with lumbar degenerative disease treated with Initial VEOS PEEK®-Optima system (Innov'Spine, France) composed of rods made from PEEK-OPTIMA® polymer (Invibio Biomaterial Solutions, UK) without arthrodesis. With an average follow-up of 2 years and half, the chances of reoperation were significantly reduced (4.8%), quality of life was improved (ODI = 16%), and the adjacent disc was preserved in more than 70% of cases. Based on these results, combined with the biomechanical and clinical data already published, PEEK rods systems can be considered as a safe and effective alternative solution to rigid ones. PMID:26981285

  13. Symptomatic lumbar epidural varices. Report of two cases.

    PubMed

    Zimmerman, G A; Weingarten, K; Lavyne, M H

    1994-05-01

    Lumbar epidural varices have been infrequently described in the literature and rarely accepted as a primary pathophysiological entity. The authors' total experience with symptomatic lumbar epidural varices over the last 15 years includes four cases (incidence 0.067% of all lumbar spine operations), two of which are described in detail in this paper. The mechanism for their formation is proposed: central disc herniations obstruct the anterior epidural venous flow leading to anterolateral caudal venous distention. Subsequent venous endothelial injury predisposes to varying degrees of phlebothrombosis. Decompression of partially thrombosed varices may occur during operative discectomy or spontaneously during regression of the nonoperated disc prolapse. Regression of the central disc herniation may also explain the "disappearing disc" phenomenon, in which patients with clinical and radiographic evidence of apparently large caudal disc herniations exhibit clinical and radiographic resolution. Magnetic resonance (MR) imaging characteristics of the epidural varix depend upon the degree of thrombosis within this anomaly. A thrombosed varix is hyperintense on T1-weighted, proton-density, and T2-weighted images, whereas flowing blood is hypointense. The variable hypo- and hyperintensity on the T2-weighted MR imaging sequences correlate with a partially patent lumen within the varix. PMID:8169634

  14. Acute formation of lumbar discal cyst: what is the mechanism?

    PubMed

    Aydin, S; Kucukyuruk, B; Yildirim, H; Abuzayed, B; Bozkus, H; Vural, M

    2010-12-01

    Lumbar discal cysts are extremely rare pathologies, with only few reports describing these lesions in the literature. Moreover, their definite pathogenesis is still unknown, with proposed theories based on radialogic and histologic findings. In this report, the authors present an acute formation of a discal cyst, which is reported for the first time. Also, we center our case on the discussion of the possible pathogenesis. Also, this is the first case of discal cyst reported in Turkey. A 67-year-old woman, whose complaints, and clinical and radiological findings demonstrated lumbar disc herniation with acute Modic 1 degererative changes of the adjacent end plates of L3-4 level. After medical and physical therapies, follow-up lumbar MRI has been taken to demonstrate a discal cyst formation on the adjacent intervertebral disc, showed cranially migrated cyst superior posterior on herniated disc, in 2 weeks period. The patient was treated by microsurgical resection of the cyst, and her complaints resolved completely. PMID:21423085

  15. Lumbar Interbody Fusion Outcomes in Degenerative Lumbar Disease : Comparison of Results between Patients Over and Under 65 Years of Age

    PubMed Central

    Jo, Dae-Jean; Jun, Jae-Kyun; Kim, Ki-Tack

    2010-01-01

    Objective To evaluate the clinical and radiological outcomes of lumbar interbody fusion and its correlation with various factors (e.g., age, comorbidities, fusion level, bone quality) in patients over and under 65 years of age who underwent lumbar fusion surgery for degenerative lumbar disease. Methods One-hundred-thirty-three patients with lumbar degenerative disease underwent lumbar fusion surgery between June 2006 and June 2007 and were followed for more than one year. Forty-eight (36.1%) were older than 65 years of age (group A) and 85 (63.9%) were under 65 years of age (group B). Diagnosis, comorbidities, length of hospital stay, and perioperative complications were recorded. The analysis of clinical outcomes was based on the visual analogue scale (VAS). Radiological results were evaluated using plain radiographs. Clinical outcomes, radiological outcomes, length of hospital stay, and complication rates were analyzed in relation to lumbar fusion level, the number of comorbidities, bone mineral density (BMD), and age. Results The mean age of the patients was 61.2 years (range, 33-86 years) and the mean BMD was -2.2 (range, -4.8 to -2.8). The mean length of hospital stay was 15.0 days (range, 5-60 days) and the mean follow-up was 23.0 months (range, 18-30 months). Eighty-five (64.0%) patients had more than one preoperative comorbidities. Perioperative complications occurred in 27 of 133 patients (20.3%). The incidence of overall complication was 22.9% in group A, and 18.8% in group B but there was no statistical difference between the two groups. The mean VAS scores for the back and leg were significantly decreased in both groups (p < 0.05), and bony fusion was achieved in 125 of 133 patients (94.0%). There was no significant difference in bony union rates between groups A and B (91.7% in group A vs. 95.3% in group B, p = 0.398). In group A, perioperative complications were more common with the increase in fusion level (p = 0.027). Perioperative complications in

  16. Minimal invasive transforaminal lumbar interbody fusion versus open transforaminal lumbar interbody fusion

    PubMed Central

    Kulkarni, Arvind G; Bohra, Hussain; Dhruv, Abhilash; Sarraf, Abhishek; Bassi, Anupreet; Patil, Vishwanath M

    2016-01-01

    Background: The aim of the present prospective study is to evaluate whether the touted advantages of minimal invasive-transforaminal lumbar interbody fusion (MI-TLIF) translate into superior, equal, or inferior outcomes as compared to open-transforaminal lumbar interbody fusion (O-TLIF). This is the first study from the Indian subcontinent prospectively comparing the outcomes of MI-TLIF and O-TLIF. Materials and Methods: All consecutive cases of open and MI-TLIF were prospectively followed up. Single-level TLIF procedures for spondylolytic and degenerative conditions (degenerative spondylolisthesis, central disc herniations) operated between January 2011 and January 2013 were included. The pre and postoperative Oswestry Disability Index (ODI) and visual analog scale (VAS) for back pain and leg pain, length of hospital stay, operative time, radiation exposure, quantitative C-reactive protein (QCRP), and blood loss were compared between the two groups. The parameters were statistically analyzed (using IBM® SPSS® Statistics version 17). Results: 129 patients underwent TLIF procedure during the study period of which, 71 patients (46 MI-TLIF and 25 O-TLIF) fulfilled the inclusion criteria. Of these, a further 10 patients were excluded on account of insufficient data and/or no followup. The mean followup was 36.5 months (range 18-54 months). The duration of hospital stay (O-TLIF 5.84 days + 2.249, MI-TLIF 4.11 days + 1.8, P < 0.05) was shorter in MI-TLIF cases. There was less blood loss (open 358.8 ml, MI 111.81 ml, P < 0.05) in MI-TLIF cases. The operative time (O-TLIF 2.96 h + 0.57, MI-TLIF 3.40 h + 0.54, P < 0.05) was longer in MI group. On an average, 57.77 fluoroscopic exposures were required in MI-TLIF which was significantly higher than in O-TLIF (8.2). There was no statistically significant difference in the improvement in ODI and VAS scores in MI-TLIF and O-TLIF groups. The change in QCRP values preoperative and postoperative was significantly lower (P < 0

  17. Clinical outcomes after posterior dynamic transpedicular stabilization with limited lumbar discectomy: Carragee classification system for lumbar disc herniations

    PubMed Central

    Kaner, Tuncay; Sasani, Mehdi; Oktenoglu, Tunc; Cosar, Murat; Ozer, Ali Fahir

    2010-01-01

    Background The observed rate of recurrent disc herniation after limited posterior lumbar discectomy is highest in patients with posterior wide annular defects, according to the Carragee classification of type II (fragment-defect) disc hernia. Although the recurrent herniation rate is lower in both type III (fragment-contained) and type IV (no fragment-contained) patients, recurrent persistent sciatica is observed in both groups. A higher rate of recurrent disc herniation and sciatica was observed in all 3 groups in comparison to patients with type I (fragment-fissure) disc hernia. Methods In total, 40 single-level lumbar disc herniation cases were treated with limited posterior lumbar microdiscectomy and posterior dynamic stabilization. The mean follow-up period was 32.75 months. Cases were selected after preoperative magnetic resonance imaging and intraoperative observation. We used the Carragee classification system in this study and excluded Carragee type I (fragment-fissure) disc herniations. Clinical results were evaluated with visual analog scale scores and Oswestry scores. Patients’ reherniation rates and clinical results were evaluated and recorded at 3, 12, and 24 months postoperatively. Results The most common herniation type in our study was type III (fragment-contained), with 45% frequency. The frequency of fragment-defects was 25%, and the frequency of no fragment-contained defects was 30%. The perioperative complications observed were as follows: 1 patient had bladder retention that required catheterization, 1 patient had a superficial wound infection, and 1 patient had a malpositioned transpedicular screw. The malpositioned screw was corrected with a second operation, performed 1 month after the first. Recurrent disc herniation was not observed during the follow-up period. Conclusions We observed that performing discectomy with posterior dynamic stabilization decreased the risk of recurrent disc herniations in Carragee type II, III, and IV groups

  18. Accretion in Saturn's F Ring

    NASA Astrophysics Data System (ADS)

    Meinke, B. K.; Esposito, L. W.; Stewart, G.

    2012-12-01

    Saturn's F ring is the solar system's principal natural laboratory for direct observation of accretion and disruption processes. The ring resides in the Roche zone, where tidal disruption competes with self-gravity, which allows us to observe the lifecycle of moonlets. Just as nearby moons create structure at the B ring edge (Esposito et al. 2012) and the Keeler gap (Murray 2007), the F ring "shepherding" moons Prometheus and Pandora stir up ring material and create observably changing structures on timescales of days to decades. In fact, Beurle et al (2010) show that Prometheus makes it possible for "distended, yet gravitationally coherent clumps" to form in the F ring, and Barbara and Esposito (2002) predicted a population of ~1 km bodies in the ring. In addition to the observations over the last three decades, the Cassini Ultraviolet Imaging Spectrograph (UVIS) has detected 27 statistically significant features in 101 occultations by Saturn's F ring since July 2004. Seventeen of those 27 features are associated with clumps of ring material. Two features are opaque in occultation, which makes them candidates for solid objects, which we refer to as Moonlets. The 15 other features partially block stellar signal for 22 m to just over 3.7 km along the radial expanse of the occultation. Upon visual inspection of the occultation profile, these features resemble Icicles, thus we will refer to them as such here. The density enhancements responsible for such signal attenuations are likely due to transient clumping of material, evidence that aggregations of material are ubiquitous in the F ring. Our lengthy observing campaign reveals that Icicles are likely transient clumps, while Moonlets are possible solid objects. Optical depth is an indicator of clumping because more-densely aggregated material blocks more light; therefore, it is natural to imagine moonlets as later evolutionary stage of icicle, when looser clumps of material compact to form a feature that appears

  19. Results of arthrospine assisted percutaneous technique for lumbar discectomy

    PubMed Central

    Kaushal, Mohinder

    2016-01-01

    Background: Avaialable minimal invasive arthro/endoscopic techniques are not compatible with 30 degree arthroscope which orthopedic surgeons uses in knee and shoulder arthroscopy. Minimally invasive “Arthrospine assisted percutaneous technique for lumbar discectomy” is an attempt to allow standard familiar microsurgical discectomy and decompression to be performed using 30° arthroscope used in knee and shoulder arthroscopy with conventional micro discectomy instruments. Materials and Methods: 150 patients suffering from lumbar disc herniations were operated between January 2004 and December 2012 by indiginously designed Arthrospine system and were evaluated retrospectively. In lumbar discectomy group, there were 85 males and 65 females aged between 18 and 72 years (mean, 38.4 years). The delay between onset of symptoms to surgery was between 3 months to 7 years. Levels operated upon included L1-L2 (n = 3), L2-L3 (n = 2), L3-L4 (n = 8), L4-L5 (n = 90), and L5-S1 (n = 47). Ninety patients had radiculopathy on right side and 60 on left side. There were 22 central, 88 paracentral, 12 contained, 3 extraforaminal, and 25 sequestrated herniations. Standard protocol of preoperative blood tests, x-ray LS Spine and pre operative MRI and pre anaesthetic evaluation for anaesthesia was done in all cases. Technique comprised localization of symptomatic level followed by percutaneous dilatation and insertion of a newly devised arthrospine system devise over a dilator through a 15 mm skin and fascial incision. Arthro/endoscopic discectomy was then carried out by 30° arthroscope and conventional disc surgery instruments. Results: Based on modified Macnab's criteria, of 150 patients operated for lumbar discectomy, 136 (90%) patients had excellent to good, 12 (8%) had fair, and 2 patients (1.3%) had poor results. The complications observed were discitis in 3 patients (2%), dural tear in 4 patients (2.6%), and nerve root injury in 2 patients (1.3%). About 90% patients were able

  20. 21 CFR 872.5550 - Teething ring.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Teething ring. 872.5550 Section 872.5550 Food and... DENTAL DEVICES Therapeutic Devices § 872.5550 Teething ring. (a) Identification. A teething ring is a...) Classification. Class I if the teething ring does not contain a fluid, such as water. The device is exempt...

  1. 21 CFR 872.5550 - Teething ring.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Teething ring. 872.5550 Section 872.5550 Food and... DENTAL DEVICES Therapeutic Devices § 872.5550 Teething ring. (a) Identification. A teething ring is a...) Classification. Class I if the teething ring does not contain a fluid, such as water. The device is exempt...

  2. 21 CFR 870.3800 - Annuloplasty ring.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Annuloplasty ring. 870.3800 Section 870.3800 Food... DEVICES CARDIOVASCULAR DEVICES Cardiovascular Prosthetic Devices § 870.3800 Annuloplasty ring. (a) Identification. An annuloplasty ring is a rigid or flexible ring implanted around the mitral or tricuspid...

  3. 21 CFR 872.5550 - Teething ring.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Teething ring. 872.5550 Section 872.5550 Food and... DENTAL DEVICES Therapeutic Devices § 872.5550 Teething ring. (a) Identification. A teething ring is a...) Classification. Class I if the teething ring does not contain a fluid, such as water. The device is exempt...

  4. 21 CFR 872.5550 - Teething ring.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Teething ring. 872.5550 Section 872.5550 Food and... DENTAL DEVICES Therapeutic Devices § 872.5550 Teething ring. (a) Identification. A teething ring is a...) Classification. Class I if the teething ring does not contain a fluid, such as water. The device is exempt...

  5. Reinforcement core facilitates O-ring installation

    NASA Technical Reports Server (NTRS)

    1965-01-01

    Reinforcement core holds O-ring in place within a structure while adjacent parts are being assembled. The core in the O-ring adds circumferential rigidity to the O-ring material. This inner core does not appreciably affect the sectional elasticity or gland-sealing characteristics of the O-ring.

  6. Plasma deposited rider rings for hot displacer

    DOEpatents

    Kroebig, Helmut L.

    1976-01-01

    A hot cylinder for a cryogenic refrigerator having two plasma spray deposited rider rings of a corrosion and abrasion resistant material provided in the rider ring grooves, wherein the rider rings are machined to the desired diameter and width after deposition. The rider rings have gas flow flats machined on their outer surface.

  7. Double acting stirling engine piston ring

    DOEpatents

    Howarth, Roy B.

    1986-01-01

    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.

  8. Prediction of the location of the lumbar aorta using the first four lumbar vertebrae as a predictor

    NASA Astrophysics Data System (ADS)

    Conrad-Hansen, Lars B.; Raundahl, Jakob; Tanko, Laszlo B.; Nielsen, Mads

    2004-05-01

    This paper is one of the first steps towards the development of a mass-screening tool, well-suited for quantizing the extend of calcific deposits in the lumbar aorta, which should deliver reliable and easily reproducible data. The major problem is that non-calcified parts of the aorta are not visible on conventional x-ray images. We investigate whether or not it is possible to predict the location of the lumbar aorta, using the first four lumbar vertebrae as prior. We build a conditional probabilistic model from 90 manually annotated datasets. Using this model we made inferences on the position of the aortic walls given the position and shape of the four vertebrae. Of particular interest is the performance of the probabilistic model in comparison to the mean aortic shape. Due to the fact that our data set for this particular study only contained 90 hand-annotated images, we evaluated the model using the "leave-one-out" method. The resulting distance from the predicted to the actual aorta was then compared to the distance from the mean aorta to the actual aorta. The obtained results are encouraging; our conditional model provides results that are up to 38% better than the prediction using only the mean shape, and yields an overlap index of 0.89, whereas the mean shape only produces 0.83.

  9. The middle layer of lumbar fascia and attachments to lumbar transverse processes: implications for segmental control and fracture

    PubMed Central

    Urquhart, Donna M.; Story, Ian H.; Fahrer, Marius; Briggs, Christopher A.

    2007-01-01

    The anatomy of the middle layer of lumbar fascia (MLF) is of biomechanical interest and potential clinical relevance, yet it has been inconsistently described. Avulsion fractures of the lumbar transverse processes (LxTP’s) are traditionally attributed to traction from psoas major or quadratus lumborum (QL), rather than transversus abdominis (TrA) acting via the MLF. This attachment is also absent from many biomechanical models of segmental control. The aims of this study were to document: (1) the morphology and attachments of the MLF and (2) the attachments of psoas and QL to the LxTP’s. Eighteen embalmed cadavers were dissected, measuring the thickness, fibre angle and width of the MLF and documenting the attachments of MLF, psoas and QL. The MLF was thicker at the level of the LxTP’s than between them (mean 0.62: 0.40 mm). Psoas attached to the anteromedial surface of each process and QL and TrA to its lateral border; QL at its upper and lower corners and TrA (via the MLF) to its tip. In three cadavers, tension applied to the MLF fractured a transverse process. The MLF has a substantial and thickened attachment to the tips of the LxTP’s which supports the involvement of TrA in lumbar segmental control and/ or avulsion fracture of the LxTP’s. PMID:17924150

  10. Concentric ring flywheel without expansion separators

    DOEpatents

    Kuklo, T.C.

    1999-08-24

    A concentric ring flywheel wherein the adjacent rings are configured to eliminate the need for differential expansion separators between the adjacent rings. This is accomplished by forming a circumferential step on an outer surface of an inner concentric ring and forming a matching circumferential step on the inner surface of an adjacent outer concentric ring. During operation the circumferential steps allow the rings to differentially expand due to the difference in the radius of the rings without the formation of gaps therebetween, thereby eliminating the need for expansion separators to take up the gaps formed by differential expansion. 3 figs.

  11. Concentric ring flywheel without expansion separators

    DOEpatents

    Kuklo, Thomas C.

    1999-01-01

    A concentric ring flywheel wherein the adjacent rings are configured to eliminate the need for differential expansion separators between the adjacent rings. This is accomplished by forming a circumferential step on an outer surface of an inner concentric ring and forming a matching circumferential step on the inner surface of an adjacent outer concentric ring. During operation the circumferential steps allow the rings to differentially expand due to the difference in the radius of the rings without the formation of gaps therebetween, thereby eliminating the need for expansion separators to take up the gaps formed by differential expansion.

  12. Morphological and postural sexual dimorphism of the lumbar spine facilitates greater lordosis in females.

    PubMed

    Bailey, Jeannie F; Sparrey, Carolyn J; Been, Ella; Kramer, Patricia A

    2016-07-01

    Previous work suggests females are evolutionarily adapted to have greater lumbar lordosis than males to aid in pregnancy load-bearing, but no consensus exists. To explore further sex-differences in the lumbar spine, and to understand contradictions in the literature, we conducted a cross-sectional retrospective study of sex-differences in lumbar spine morphology and sacral orientation. In addition, our sample includes data for separate standing and supine samples of males and females to examine potential sex-differences in postural loading on lumbosacral morphology. We measured sagittal lumbosacral morphology on 200 radiographs. Measurements include: lumbar angle (L1-S1), lumbar vertebral body and disc wedging angles, sacral slope and pelvic incidence. Lumbar angle, representative of lordotic curvature between L1 and S1, was 7.3° greater in females than males, when standing. There were no significant sex-differences in lumbar angle when supine. This difference in standing lumbar angle can be explained by greater lordotic wedging of the lumbar vertebrae (L1-L5) in females. Additionally, sacral slope was greater in females than males, when standing. There were no significant sex-differences in pelvic incidence. Our results support that females have greater lumbar lordosis than males when standing, but not when supine - suggesting a potentially greater range of motion in the female spine. Furthermore, sex-differences in the lumbar spine appear to be supported by postural differences in sacral-orientation and morphological differences in the vertebral body wedging. A better understanding of sex-differences in lumbosacral morphology may explain sex-differences in spinal conditions, as well as promote necessary sex-specific treatments. PMID:26916466

  13. Intrinsic structure in Saturn's rings

    NASA Astrophysics Data System (ADS)

    Albers, N.

    2015-10-01

    Saturn's rings are the most prominent in our Solar system and one example of granular matter in space. Dominated by tides and inelastic collisions the system is highly flattened being almost 300000km wide while only tens of meters thick. Individual particles are composed of primarily water ice and range from microns to few tens of meters in size. Apparent patterns comprise ringlets, gaps, kinematic wakes, propellers, bending waves, and the winding spiral arms of density waves. These large-scale structures are perturbations foremost created by external as well as embedded moons. Observations made by the Cassini spacecraft currently in orbit around Saturn show these structures in unprecedented detail. But high-resolution measurements reveal the presence of small-scale structures throughout the system. These include self-gravity wakes (50-100m), overstable waves (100-300m), subkm structure at the A and B ring edges, "straw" and "ropy" structures (1-3km), and the C ring "ghosts". Most of these had not been anticipated and are found in perturbed regions, driven by resonances with external moons, where the system undergoes periodic phases of compression and relaxation that correlate with the presence of structure. High velocity dispersion and the presence of large clumps imply structure formation on time scales as short as one orbit (about 10 hours). The presence of these intrinsic structures is seemingly the response to varying local conditions such as internal density, optical depth, underlying particle size distribution, granular temperature, and distance from the central planet. Their abundance provides evidence for an active and dynamic ring system where aggregation and fragmentation are ongoing on orbital timescales. Thus a kinetic description of the rings may be more appropriate than the fluid one. I will present Cassini Ultraviolet Spectrometer (UVIS) High Speed Photometer (HSP) occultations, Voyager 1 and 2 Imaging Science Subsystem (ISS), and high

  14. Thermal Studies of Saturn's Rings

    NASA Astrophysics Data System (ADS)

    Pilorz, S.; Altobelli, N.; Leyrat, C.; Spilker, L.

    2007-12-01

    The observed thermal emission from Saturn's rings has a locational and directional variation that ultimately results from the time dependent response of individual ring particles to the quasi-periodic radiation forcing they experience as they orbit Saturn. The observed thermal emission from any radial region of the rings is representative of a large ensemble of particles or structures which are subject to statistically similar conditions as they orbit. Near any particular radius, the thermal forcing and response are quasi-periodic around an orbit, varying secularly with Saturn's twenty-nine year seasonal cycle. This talk will discuss the coupled thermal and radiative transfer processes within the rings as determined by the interplay between individual particle properties and those of the ensemble (i.e., the ring structure), and the constraints that are placed on those by the most comprehensive thermal observations of the rings to date, taken with the Cassini Infrared Spectrometer (CIRS). Over one hundred thousand thermal-infrared spectra of the rings, between 10 and 500 cm-1, have been taken with the CIRS Focal Plane 1 (FP1) detector since Cassini orbit insertion in July, 2004. They resemble scaled Planck functions with well resolved peaks indicative of temperatures between approximately 60 and 120 K. We investigate the properties of a mapping from a space of physical parameters describing ring particles and their distribution onto predicted time-dependent spectral thermal emission. Ring emission is modeled using a radiative transfer code augmented with ray tracing calculations; a thermal model is embedded within the calculation to model the particles as a thermal source, and statistical averaging is incorporated. The model is specified by a vector of parameters describing a vertically varying particle size distribution, spin distribution, thermal inertia, albedo and optical depth, and when driven by radiation calculated from ephemeris parameters it produces a self

  15. Archiving of Planetary Ring Data

    NASA Technical Reports Server (NTRS)

    Elliot, James L.

    2001-01-01

    Stellar occultation data provide our only Earth-based means of probing planetary rings at kilometer spatial resolution. The occultation data archive at MIT contains original data and analysis products of stellar occultations by the ring systems of the planets Jupiter, Saturn, Uranus, and Neptune observed by members of the group (and other groups) from 1977 to the present. During this time period, several media have been used to record and store the original and processed data: (1) chart records; (2) printed output, (3) audio reel tape; (4) audio cassette tape; (5) 7-track, 1/2-inch computer tape; (6) 9-track, 1/2-inch computer tape at 800, 1600, and 6250 bpi; (7) NOVA disk platters (2.5 and 5.0 Mbyte); (8) write once optical disks; (9) punched cards; and (10) read-write optical disks. With the rapid change of computer technology over this time period, some of these media have become not only obsolete, but nearly extinct. In particular, it has become nearly impossible to find any facilities that can still read 800 bpi tapes, which contain the only copies of several important data sets for the ring system of Uranus. In particular, we have an extensive ring data collection that includes data sets for the following Uranian ring occultations: U0, U11, U12, U13, U14, U25, U17, and U36.

  16. Split ring containment attachment device

    SciTech Connect

    Sammel, A.G.

    1995-12-31

    A containment attachment device is described for operatively connecting a glovebag to plastic sheeting covering hazardous material. The device includes an inner split ring member connected on one end to a middle ring member wherein the free end of the split ring member is inserted through a slit in the plastic sheeting to captively engage a generally circular portion of the plastic sheeting. A collar portion having an outer ring portion is provided with fastening means for securing the device together wherein the glovebag is operatively connected to the collar portion. Hazardous material such as radioactive waste may be sealed in plastic bags for small items or wrapped in plastic sheeting for large items. Occasionally the need arises to access the hazardous material in a controlled manner, that is, while maintaining total containment. Small items could be placed entirely inside a containment glovebag. However, it may not be possible or practical to place large items inside a containment; instead, one or more glovebags could be attached to the plastic sheeting covering the hazardous material. It is this latter application for which the split ring containment attachment device is intended.

  17. Ring wormholes via duality rotations

    NASA Astrophysics Data System (ADS)

    Gibbons, Gary W.; Volkov, Mikhail S.

    2016-09-01

    We apply duality rotations and complex transformations to the Schwarzschild metric to obtain wormhole geometries with two asymptotically flat regions connected by a throat. In the simplest case these are the well-known wormholes supported by phantom scalar field. Further duality rotations remove the scalar field to yield less well known vacuum metrics of the oblate Zipoy-Voorhees-Weyl class, which describe ring wormholes. The ring encircles the wormhole throat and can have any radius, whereas its tension is always negative and should be less than -c4 / 4 G. If the tension reaches the maximal value, the geometry becomes exactly flat, but the topology remains non-trivial and corresponds to two copies of Minkowski space glued together along the disk encircled by the ring. The geodesics are straight lines, and those which traverse the ring get to the other universe. The ring therefore literally produces a hole in space. Such wormholes could perhaps be created by negative energies concentrated in toroidal volumes, for example by vacuum fluctuations.

  18. Ring Beholds a Delicate Flower

    NASA Technical Reports Server (NTRS)

    2005-01-01

    NASA's Spitzer Space Telescope finds a delicate flower in the Ring Nebula, as shown in this image. The outer shell of this planetary nebula looks surprisingly similar to the delicate petals of a camellia blossom. A planetary nebula is a shell of material ejected from a dying star. Located about 2,000 light years from Earth in the constellation Lyra, the Ring Nebula is also known as Messier Object 57 and NGC 6720. It is one of the best examples of a planetary nebula and a favorite target of amateur astronomers.

    The 'ring' is a thick cylinder of glowing gas and dust around the doomed star. As the star begins to run out of fuel, its core becomes smaller and hotter, boiling off its outer layers. The telescope's infrared array camera detected this material expelled from the withering star. Previous images of the Ring Nebula taken by visible-light telescopes usually showed just the inner glowing loop of gas around the star. The outer regions are especially prominent in this new image because Spitzer sees the infrared light from hydrogen molecules. The molecules emit infrared light because they have absorbed ultraviolet radiation from the star or have been heated by the wind from the star.

    Download the QuickTime movie for the animated version of this Ring Nebula image.

  19. Softened-Stainless-Steel O-Rings

    NASA Technical Reports Server (NTRS)

    Marquis, G. A.; Waters, William I.

    1993-01-01

    In fabrication of O-ring of new type, tube of 304 stainless steel bent around mandril into circle and welded closed into ring. Ring annealed in furnace to make it soft and highly ductile. In this condition, used as crushable, deformable O-ring seal. O-ring replacements used in variety of atmospheres and temperatures, relatively inexpensive, fabricated with minimum amount of work, amenable to one-of-a-kind production, reusable, and environmentally benign.

  20. A diffusion and T2 relaxation MRI study of the ovine lumbar intervertebral disc under compression in vitro

    NASA Astrophysics Data System (ADS)

    Drew, Simon C.; Silva, Pujitha; Crozier, Stuart; Pearcy, Mark J.

    2004-08-01

    The ovine lumbar intervertebral disc is a useful model for the human lumbar disc. We present preliminary estimates of diffusion coefficients and T2 relaxation times in a pilot MRI study of the ovine lumbar intervertebral disc during uniaxial compression in vitro, and identify factors that hamper the ability to accurately monitor the temporal evolution of the effective diffusion tensor at high spatial resolution.

  1. Remote Sensing of Dipole Rings

    NASA Technical Reports Server (NTRS)

    Hooker, Stanford B.; Mied, Richard P.; Brown, James W.; Kirwan, A. D., Jr.

    1997-01-01

    Historical satellite-derived sea surface temperature (SST) data are reanalyzed with a zebra color palette and a thermal separatrix method. The new results from this reanalysis are as follows: (a) Thirteen observational sequences of six rings from the Gulf Stream and the Brazil Current, which have historically been interpreted as solitary vortices or monopoles are shown to have a dipolar character; (b) some of these dipole rings have been observed in the open ocean, thereby eliminating the possibility that they are sustained by topographic interactions with the continental slope; (c) whether interacting with other features or evolving as isolated circulations, dipoles are seen to rotate within a relatively narrow range of approximately 4-8 deg/day (interacting) and 10-11 deg/day (isolated); and (d) feature tracking delineates energetic fluid in both vortices and eliminates the possibility of interpreting dipole rings as transient features produced by active monopoles and patches of entrained fluid.

  2. New Main Ring control system

    SciTech Connect

    Seino, K.; Anderson, L.; Ducar, R.; Franck, A.; Gomilar, J.; Hendricks, B.; Smedinghoff, J.

    1990-03-01

    The Fermilab Main Ring control system has been operational for over sixteen years. Aging and obsolescence of the equipment make the maintenance difficult. Since the advent of the Tevatron, considerable upgrades have been made to the controls of all the Fermilab accelerators except the Main Ring. Modernization of the equipment and standardization of the hardware and software have thus become inevitable. The Tevatron CAMAC serial system has been chosen as a basic foundation in order to make the Main Ring control system compatible with the rest of the accelerator complex. New hardware pieces including intelligent CAMAC modules have been designed to satisfy unique requirements. Fiber optic cable and repeaters have been installed in order to accommodate new channel requirements onto the already saturated communication medium system. 8 refs., 2 figs.

  3. Diagnostic possibilities of thermal imaging in neurologic manifestations of lumbar osteochondrosis in different stages of treatment

    NASA Astrophysics Data System (ADS)

    Kolesov, S. N.; Fedosenko, T. S.

    1993-11-01

    On the basis of thermal imaging examinations of 2000 patients suffering lumbar osteochondrosis of the vertebral region, and using their methods, the authors describe the specifics of the thermal images of the lumbar region and the lower extremities in various clinical manifestations of the reflex and radicular syndromes.

  4. Lumbar stabilization: a review of core concepts and current literature, part 2.

    PubMed

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

    2007-01-01

    Lumbar-stabilization exercise programs have become increasingly popular as a treatment for low-back pain. In this article, we outline an evidence-based medicine approach to evaluating patients for a lumbar-stabilization program. We also discuss typical clinical components of this type of program and the rationale for including these particular features based on the medical literature.

  5. Comparison of chronic low-back pain patients hip range of motion with lumbar instability

    PubMed Central

    Lee, Sang wk; Kim, Suhn Yeop

    2015-01-01

    [Purpose] The purpose of this study was to compare differences in hip range of motion between a lumbar stability group and a lumbar instability group of patients with chronic low-back pain. [Subjects] Sixty-nine patients with chronic low-back pain were divided into two groups: a lumbar stability group (n=39) and a lumbar instability group (n=30). [Methods] The patients were assessed using a goniometer to evaluate the hip range of motion at pre-test. Data were analyzed using SPSS 18.0 software for Windows. The experimental data were analyzed using one-way ANOVA, repeated one-way ANOVA, and the t-test, and a significance level of 0.05. [Results] The limitation of hip range of motion of the lumbar instability group was significantly greater than that of the lumbar stability group. [Conclusion] The chronic low-back pain patients showed greater limitation of hip range of motion than healthy persons, and among them, those who had lumbar instability showed greater limitation than those with lumbar stability. PMID:25729165

  6. Lumbar hernia treated with lightweight partially absorbable mesh: report of a case.

    PubMed

    Yamaguchi, Shohei; Tsutsumi, Norifumi; Kusumoto, Eiji; Endo, Kazuya; Ikejiri, Koji; Yamashita, Yo-ichi; Uchiyama, Hideaki; Saeki, Hiroshi; Oki, Eiji; Kawanaka, Hirofumi; Morita, Masaru; Ikeda, Tetsuo; Maehara, Yoshihiko

    2013-12-01

    Superior lumbar hernia, also known as Grynfeltt-Lesshaft hernia, is an uncommon abdominal wall defect. We report a case of superior lumbar hernia, which was successfully treated with a lightweight partially absorbable mesh. A 73-year-old man visited our department with complaints of lumbar pain and a feeling of pressure associated with a right lumbar mass. A CT scan of the abdomen demonstrated a defect in the aponeurosis of the transversus abdominis muscle and a protrusion of the small intestine through the defect. The diagnosis of a right superior lumbar hernia was made. The lumbar hernia was surgically treated with a lightweight large-pore polypropylene mesh containing an absorbable component consisting of poliglecaprone (ULTRAPRO Plug). The patient had no evidence of recurrence after 4 years of follow-up without any sense of discomfort. This is the first case report of a lumbar hernia treated with a lightweight partially absorbable mesh. This partially absorbable mesh can be considered to be suitable for the treatment of a lumbar hernia.

  7. Intrasession reliability and influence of breathing during clinical assessment of lumbar spine postural control.

    PubMed

    Lafond, Danik; Dimmock, Mathilde; Champagne, Annick; Descarreaux, Martin

    2009-04-01

    The aims of this study were to evaluate the influence of breathing when measuring lumbar postural control during a clinical progressive lumbar stabilization test (LST) and to estimate the intrasession reliability of the LST. The lumbar postural control index was calculated by using a biofeedback pressure unit. The LST was performed in two different positions (crook lying and upright) and two respiratory conditions (apnea and breathing) by 20 healthy individuals. The intrasession reliability of the lumbar postural control index of one trial was estimated with intraclass correlation coefficient (ICC) based on an Anova model. The results showed that the lumbar postural control index is similar between testing positions. There is an increase of the lumbar postural control index during breathing compared to the apnea. The reliability of the lumbar postural control index was fair to good (ICC 0.28-0.58). We also found that for the apnea, three trials had to be averaged to attain an ICC of 0.80 for both positions. The results of the present study indicate that the progressive LST can be similarly conducted in either supine or upright posture. Clinicians should be aware of the influence of breathing during LST. However, breathing could also serve as a clinical strategy to challenge lumbar spine postural control and stability during bracing therapeutic exercises. PMID:19384740

  8. Clinical applications of diffusion magnetic resonance imaging of the lumbar foraminal nerve root entrapment

    PubMed Central

    Ohtori, Seiji; Yamashita, Masaomi; Yamauchi, Kazuyo; Suzuki, Munetaka; Orita, Sumihisa; Kamoda, Hiroto; Arai, Gen; Ishikawa, Tetsuhiro; Miyagi, Masayuki; Ochiai, Nobuyasu; Kishida, Shunji; Masuda, Yoshitada; Ochi, Shigehiro; Kikawa, Takashi; Takaso, Masashi; Aoki, Yasuchika; Toyone, Tomoaki; Suzuki, Takane; Takahashi, Kazuhisa

    2010-01-01

    Diffusion-weighted imaging (DWI) can provide valuable structural information about tissues that may be useful for clinical applications in evaluating lumbar foraminal nerve root entrapment. Our purpose was to visualize the lumbar nerve root and to analyze its morphology, and to measure its apparent diffusion coefficient (ADC) in healthy volunteers and patients with lumbar foraminal stenosis using 1.5-T magnetic resonance imaging. Fourteen patients with lumbar foraminal stenosis and 14 healthy volunteers were studied. Regions of interest were placed at the fourth and fifth lumbar root at dorsal root ganglia and distal spinal nerves (at L4 and L5) and the first sacral root and distal spinal nerve (S1) on DWI to quantify mean ADC values. The anatomic parameters of the spinal nerve roots can also be determined by neurography. In patients, mean ADC values were significantly higher in entrapped roots and distal spinal nerve than in intact ones. Neurography also showed abnormalities such as nerve indentation, swelling and running transversely in their course through the foramen. In all patients, leg pain was ameliorated after selective decompression (n = 9) or nerve block (n = 5). We demonstrated the first use of DWI and neurography of human lumbar nerves to visualize and quantitatively evaluate lumbar nerve entrapment with foraminal stenosis. We believe that DWI is a potential tool for diagnosis of lumbar nerve entrapment. PMID:20632042

  9. A minimally invasive technique for percutaneous lumbar facet augmentation: Technical description of a novel device

    PubMed Central

    Smith, Zachary A.; Armin, Sean; Raphael, Dan; Khoo, Larry T.

    2011-01-01

    Background: We describe a new posterior dynamic stabilizing system that can be used to augment the mechanics of the degenerating lumbar segment. The mechanism of this system differs from other previously described surgical techniques that have been designed to augment lumbar biomechanics. The implant and technique we describe is an extension-limiting one, and it is designed to support and cushion the facet complex. Furthermore, it is inserted through an entirely percutaneous technique. The purpose of this technical note is to demonstrate a novel posterior surgical approach for the treatment of lumbar degenerative. Methods: This report describes a novel, percutaneously placed, posterior dynamic stabilization system as an alternative option to treat lumbar degenerative disk disease with and without lumbar spinal stenosis. The system does not require a midline soft-tissue dissection, nor subperiosteal dissection, and is a truly minimally invasive means for posterior augmentation of the functional facet complex. This system can be implanted as a stand-alone procedure or in conjunction with decompression procedures. Results: One-year clinical results in nine individual patients, all treated for degenerative disease of the lower lumbar spine, are presented. Conclusions: This novel technique allows for percutaneous posterior dynamic stabilization of the lumbar facet complex. The use of this procedure may allow a less invasive alternative to traditional approaches to the lumbar spine as well as an alternative to other newly developed posterior dynamic stabilization systems. PMID:22145084

  10. Lymphocele formation after anterior lumbar interbody fusion at L4-5. Case report.

    PubMed

    Pee, Yong Hun; Kim, Ki Joon; Choi, Young-Geun; Jeon, Sang Hyeop; Park, Jong Dae; Lee, Sang-Ho

    2007-11-01

    In this report, the authors present the case of patient with a lymphocele in the retroperitoneal area following anterior lumbar interbody fusion at L4-5. A lymphocele is a rare complication of spinal operations, especially lower lumbar spinal surgeries. The authors discuss this complicating factor and describe its features and treatments.

  11. Transforaminal ligament may play a role in lumbar nerve root compression of foraminal stenosis.

    PubMed

    Qian, Yu; Qin, An; Zheng, Ming H

    2011-12-01

    Lumbar foraminal stenosis is a common pathological change, and lumbar nerve root compression in stenotic foramina was recently considered as one of the main causes of low back pain and leg pain. However, the exact mechanism of lumbar nerve root compression in foramina is still not clear. Previous studies indicated that loss of the intervertebral disc height could reduce the cross-sectional area of lumbar foramina, while lumbar nerve root compression by boundaries of foramina has not been observed in experimental reduction of the intervertebral disc height. Given the close anatomic relationship between transforaminal ligaments and lumbar nerve roots, we hypothesize that transforaminal ligament can be the leading cause of lumbar nerve root compression in foraminal stenosis. We also propose that there are two possible mechanisms of lumbar nerve root compression by transforaminal ligaments: (1) nerve roots are compressed by the transforaminal ligament which moves downward with the loss of the intervertebral disc height; (2) pathological transforaminal ligaments increase the risk of nerve root compression in foramina.

  12. Older literature review of increased risk of adjacent segment degeneration with instrumented lumbar fusions

    PubMed Central

    Epstein, Nancy E.

    2016-01-01

    Background: Adjacent segment degeneration (ASD) following lumbar spine surgery occurs in up to 30% of cases, and descriptions of such changes are not new. Here, we review some of the older literature concerning the rate of ASD, typically more severe cephalad than caudad, and highly correlated with instrumented fusions. Therefore, for degenerative lumbar disease without frank instability, ASD would be markedly reduced by avoiding instrumented fusions. Methods: In a prior review, the newer literature regarding the frequency of ASD following lumbar instrumented fusions (e.g., transforaminal or posterior lumbar interbody fusions [TLIF/PLIF] fusions or occasionally, posterolateral fusions [PLFs]) was presented. Some studies cited an up to an 18.5% incidence of ASD following instrumented versus noninstrumented fusions/decompressions alone (5.6%). A review of the older literature similarly documents a higher rate of ASD following instrumented fusions performed for degenerative lumbar disease alone. Results: More frequent and more severe ASD follows instrumented lumbar fusions performed for degenerative lumbar disease without instability. Alternatively, this entity should be treated with decompressions alone or with noninstrumented fusions, without the addition of instrumentation. Conclusions: Too many studies assume that TLIF, PLIF, and even PLF instrumented fusions are the “gold standard of care” for dealing with degenerative disease of the lumbar spine without documented instability. It is time to correct that assumption, and reassess the older literature along with the new to confirm that decompression alone and noninstrumented fusion avoid significant morbidity and even potentially mortality attributed to unnecessary instrumentation. PMID:26904370

  13. Remote cerebellar hemorrhage as an early and potentially lethal complication of a discal lumbar herniation surgery.

    PubMed

    Royon, V; Rabehenoina, C; Tourrel, F; Compère, V; Dureuil, B

    2014-01-01

    Remote cerebellar hemorrhage (RCH) is an infrequent but serious complication after lumbar herniation surgery. Little is known about this complication but excessive cerebrospinal fluid (CSF) leakage is thought to be a leading cause of RCH. We describe the case of a patient suffering from a life-threatening RCH, which occurred a few hours after lumbar disc herniation surgery. PMID:24439492

  14. Physics of Jupiter's Gossamer Rings

    NASA Astrophysics Data System (ADS)

    Hamilton, Douglas P.; Krueger, H.

    2008-05-01

    Thebe's gossamer ring, the outermost and faintest of Jupiter's rings, extends outward by at least half a jovian radius from its source satellite while maintaining a constant vertical thickness. This structure is created by an electromagnetic perturbation known as a shadow resonance (Hamilton 2003, DPS meeting #35, #11.09). A shadow resonance arises from the abrupt shutoff of photoelectric charging when a dust particle enters Jupiter's shadow which, in turn, affects the strength of the electromagnetic perturbation from the planet's intense magnetic field. The result is a coupled oscillation between a particle's orbital eccentricity and its semimajor axis. Ring material spreads outward from Thebe while maintaining its vertical thickness just as observed by Galileo imaging. In addition to cameras, the Galileo spacecraft was also equipped with dust and plasma detectors. The spacecraft made two passes through the ring and its dust detector found that 1) dust fluxes drop immediately interior to Thebe's orbit, 2) some grains have inclinations in excess of 20 degrees and 3) submicron particles are present in the Amalthea ring in much greater numbers than in the Thebe ring. These findings can all be explained in the context of our shadow resonance model: the inner boundary is a direct consequence of the conservation of the Electromagnetic Jacobi Constant, the high inclinations are forced by a vertical version of the shadow resonance, and the excess submicron particles are a consequence of the weakening of electromagnetic forces in the vicinity of synchronous orbit. In this talk, we will present the data sets as well as detailed numerical simulations that back up these claims.

  15. Ynamides in Ring Forming Transformations

    PubMed Central

    WANG, XIAO-NA; YEOM, HYUN-SUK; FANG, LI-CHAO; HE, SHUZHONG; MA, ZHI-XIONG; KEDROWSKI, BRANT L.; HSUNG, RICHARD P.

    2013-01-01

    Conspectus The ynamide functional group activates carbon-carbon triple bonds through an attached nitrogen atom that bears an electron-withdrawing group. As a result, the alkyne has both electrophilic and nucleophilic properties. Through the selection of the electron-withdrawing group attached to nitrogen chemists can modulate the electronic properties and reactivity of ynamides, making these groups versatile synthetic building blocks. The reactions of ynamides also lead directly to nitrogen-containing products, which provides access to important structural motifs found in natural products and molecules of medicinal interest. Therefore, researchers have invested increasing time and research in the chemistry of ynamides in recent years. This Account surveys and assesses new organic transformations involving ynamides developed in our laboratory and in others around the world. We showcase the synthetic power of ynamides for rapid assembly of complex molecular structures. Among the recent reports of ynamide transformations, ring-forming reactions provide a powerful tool for generating molecular complexity quickly. In addition to their synthetic utility, such reactions are mechanistically interesting. Therefore, we focus primarily on the cyclization chemistry of ynamides. This Account highlights ynamide reactions that are useful in the rapid synthesis of cyclic and polycyclic structural manifolds. We discuss the mechanisms active in the ring formations and describe representative examples that demonstrate the scope of these reactions and provide mechanistic insights. In this discussion we feature examples of ynamide reactions involving radical cyclizations, ring-closing metathesis, transition metal and non-transition metal mediated cyclizations, cycloaddition reactions, and rearrangements. The transformations presented rapidly introduce structural complexity and include nitrogen within, or in close proximity to, a newly formed ring (or rings). Thus, ynamides have emerged

  16. Power Supplies for Precooler Ring

    SciTech Connect

    Fuja, Raymond; Praeg, Walter

    1980-12-12

    Eight power supplies will energize the antiproton Precooler ring. there will be two series connected supplies per quadrant. These supplies will power 32 dipole and 19 quadrupole magnets. The resistance and inductance per quadrant is R = 1.4045 Ohms and L = 0.466. Each powr supply will have 12-phase series bridge rectifiers and will be energized from the 480 V 3-phase grid. The total of eight power supplies are numbered IA, IIA, IIIA, IVA, and IB, IIB, IIIB, and IVB. Each quadrant will contain one A and one B supply. A block diagram of the Precooler ring with its power supplies is shown in Figure 1.

  17. Effects of pelvic stabilization on lumbar muscle activity during dynamic exercise.

    PubMed

    San Juan, Jun G; Yaggie, James A; Levy, Susan S; Mooney, Vert; Udermann, Brian E; Mayer, John M

    2005-11-01

    Many commonly utilized low-back exercise devices offer mechanisms to stabilize the pelvis and to isolate the lumbar spine, but the value of these mechanisms remains unclear. The purpose of this study was to examine the effect of pelvic stabilization on the activity of the lumbar and hip extensor muscles during dynamic back extension exercise. Fifteen volunteers in good general health performed dynamic extension exercise in a seated upright position on a lumbar extension machine with and without pelvic stabilization. During exercise, surface electromyographic activity of the lumbar multifidus and biceps femoris was recorded. The activity of the multifidus was 51% greater during the stabilized condition, whereas there was no difference in the activity of the biceps femoris between conditions. This study demonstrates that pelvic stabilization enhances lumbar muscle recruitment during dynamic exercise on machines. Exercise specialists can use these data when designing exercise programs to develop low back strength.

  18. The knee-spine syndrome. Association between lumbar lordosis and extension of the knee.

    PubMed

    Murata, Yasuaki; Takahashi, Kazuhisa; Yamagata, Masatsune; Hanaoka, Eiji; Moriya, Hideshige

    2003-01-01

    Degenerative changes of the knee often cause loss of extension. This may affect aspects of posture such as lumbar lordosis. A total of 366 patients underwent radiological examination of the lumbar spine in a standing position. The knee and body angles were measured by physical examination using a goniometer. Limitation of extension of the knee was significantly greater in patients whose lumbar lordosis was 30 degrees or less. Lumbar lordosis was significantly reduced in patients whose limitation of extension of the knee was more than 5 degrees. It decreased over the age of 70 years, and the limitation of extension of the knee increased over the age of 60 years. Our study indicates that symptoms from the lumbar spine may be caused by degenerative changes in the knee. This may be called the 'knee-spine syndrome'. PMID:12585585

  19. Evaluation of the influence of pedicle-lengthening osteotomy on lumbar stability

    PubMed Central

    Gao, Maofeng; Zou, Jun; Zhang, Zhigang; Luo, Zongping; Yang, Huilin

    2016-01-01

    Pedicle-lengthening osteotomy (PLO) is a minimally invasive and effective surgical procedure for lumbar spinal stenosis syndrome. Compared with traditional surgery, PLO can effectively enlarge the spinal canal while minimizing the disruption of posterior anatomical structures of the lumbar vertebra, leading to reduced postoperative perineural scarring adhesion and good clinical outcomes using minimally invasive procedures. However, PLO is still in its early stages, and only a few relevant experimental and clinical studies have been reported. The present study was performed to investigate the influence of PLO on the stability of lumbar vertebrae. The results indicated that PLO can effectively enlarge the spinal canal, and no lumbar spondylolisthesis or other complications occurred in this study. Moreover, this procedure does not significantly affect the stability of the lumbar spine, suggesting a possible clinical application. PMID:27347315

  20. Factors associated with the subject's ability to quantify their lumbar flexion demands at work.

    PubMed

    Martin, Friedrich; Matthias, Pallamar

    2006-02-01

    Continuous measurements of lumbar posture provide the basis for determining the factors influencing the difference between subjective and objective assessments of lumbar posture. The lumbar flexion posture during an entire work day was registered in a group of 13 sewage workers and 14 physical therapists. Subjective lumbar posture data, perceived occupational stress, job satisfaction and 12 month prevalence of low back pain were obtained using standardized questionnaires. For the entire sample, a significant positive correlation was found between the degree of overestimation of the lumbar bending demands at work and the level of occupational stress (p > 0.01) as well as the low back pain prevalence in the past 12 months. Continuous measurement of spinal posture is an important tool not only for comparisons of posture demands during various activities but also for investigations into the complex interactions between the biomechanical and psychosocial determinants of low back pain. PMID:16507482

  1. [Monitoring by non-flowmeter vascular function tests following lumbar sympathectomy].

    PubMed

    Becker, F; Davinroy, M

    1985-01-01

    Postoperative follow up examinations were conducted using vascular functional explorations (V.F.E.) including thermometry, Doppler, irrigraphy, digital plethysmography and tread mill. Immediate and long-term effects of lumbar sympathectomy have to be distinguished: the majority of hemodynamic variations noted are not due exclusively to lumbar sympathectomy, except for the iatrogenic development of vasomotor inertia (R.H.T. indifferent or negative) and perhaps values with time of the digital flow curve. Results of V.F.E. after lumbar sympathectomy are discussed in relation to three modalities and taking into account the efficacy and extent of the sympathetic chain resection. The question is raised as to the usefulness of lumbar sympathectomy when the pretreatment V.F.E. findings show hemodynamic elements of the type that would be expected after lumbar sympathectomy.

  2. Differences between clinical "snap-shot" and "real-life" assessments of lumbar spine alignment and motion - What is the "real" lumbar lordosis of a human being?

    PubMed

    Dreischarf, Marcel; Pries, Esther; Bashkuev, Maxim; Putzier, Michael; Schmidt, Hendrik

    2016-03-21

    The individual lumbar lordosis and lumbar motion have been identified to play an important role in pathogenesis of low back pain and are essential references for preoperative planning and postoperative evaluation. The clinical "gold-standard" for measuring lumbar lordosis and its motion are radiological "snap-shots" taken while standing and during upper-body flexion and extension. The extent to which these clinically assessed values characterise lumbar alignment and its motion in daily life merits discussion. A non-invasive measurement-system was employed to measure lumbar lordosis and lumbar motion in 208 volunteers (age: 20-74yrs; ♀/♂: 115/93). For an initial short-term measurement, comparable with the clinical "snap-shot", lumbar lordosis and its motion were assessed while standing and during flexion and extension. Subsequently, volunteers were released to their daily lives while wearing the device, and measurements were performed during the following 24h. The average lumbar lordosis during 24h (8.0°) differed significantly from the standardised measurement while standing (33.3°). Ranges of motion were significantly different throughout the day compared to standing measurements. The influence of the factors age and gender on lordosis and its motion resulted in conflicting results between long- and short-term-measurements. In conclusion, results of short-term examinations differ considerably from the average values during real-life. These findings might be important for surgical planning and increase the awareness of the biomechanical challenges that spinal structures and implants face in real-life. Furthermore, long-term assessments of spinal alignment and motion during daily life can provide valid data on spinal function and can reveal the importance of influential factors. PMID:26900033

  3. A Experimental Study of Viscous Vortex Rings.

    NASA Astrophysics Data System (ADS)

    Dziedzic, Mauricio

    Motivated by the role played by vortex rings in the process of turbulent mixing, the work is focused on the problem of stability and viscous decay of a single vortex ring. A new classification is proposed for vortex rings which is based on extensive hot-wire measurements of velocity in the ring core and wake and flow visualization. Vortex rings can be classified as laminar, wavy, turbulence-producing, and turbulent. Prediction of vortex ring type is shown to be possible based on the vortex ring Reynolds number. Linear growth rates of ring diameter with time are observed for all types of vortex rings, with different growth rates occurring for laminar and turbulent vortex rings. Data on the viscous decay of vortex rings are used to provide experimental confirmation of the accuracy of Saffman's equation for the velocity of propagation of a vortex ring. Experimental data indicate that instability of the vortex ring strongly depends on the mode of generation and can be delayed by properly adjusting the generation parameters. A systematic review of the literature on vortex-ring interactions is presented in the form of an appendix, which helps identify areas in which further research may be fruitful.

  4. Lumbar Puncture in HIV-Infected Patients with Syphilis and No Neurologic Symptoms

    PubMed Central

    Ghanem, Khalil G.; Moore, Richard D.; Rompalo, Anne M.; Erbelding, Emily J.; Zenilman, Jonathan M.; Gebo, Kelly A.

    2009-01-01

    Background The decision to perform lumbar puncture in patients with asymptomatic human immunodeficiency virus (HIV) infection and syphilis is controversial. The Centers for Disease Control and Prevention recommend certain criteria that warrant lumbar puncture. Here, we assess the performance of these criteria for detecting asymptomatic neurosyphilis (ANS). Methods Eligible subjects consisted of all patients with concurrent HIV infection and syphilis in a prospective clinical cohort who had no neurologic symptoms at the time of lumbar puncture. We retrospectively applied different stratification criteria to calculate the performance of lumbar puncture in detecting ANS: (1) lumbar puncture in patients with late latent syphilis or syphilis of an unknown duration, regardless of the CD4 cell count or rapid plasma reagin titer; (2) lumbar puncture if the CD4 cell count was ≤350 cells/mL and/or the rapid plasma reagin titer was ≥1:32, regardless of the syphilis stage; and (3) lumbar puncture in the context of serologic nonresponse to syphilis therapy. Results Two hundred two of 231 patients with syphilis did not have neurologic symptoms. Immediate lumbar puncture was performed for 46 patients, and 10 cases (22%) of ANS were detected. With use of the first criterion, 2 (14%) of 10 cases of ANS in patients with early-stage syphilis would have been missed (sensitivity, 80% [95% confidence interval {CI}, 44%–97%]; specificity, 76% [95% CI, 60%–89%]). Criterion 2 would not have missed any cases of ANS (sensitivity, 100% [95% CI, 70%–100%]; specificity, 87% [95% CI, 72%–96%]) but would have required that a lumbar puncture be performed for 88% of patients. Performance of lumbar puncture performed in 13 cases based on serologic nonresponse to syphilis therapy yielded 4 cases (31%) of ANS. Conclusions In patients with concurrent HIV infection and syphilis, the use of criteria based on rapid plasma reagin titer and CD4 cell count, instead of stage-based criteria

  5. Impact of Preoperative Hematocrit Level on Length of Stay after Surgery on the Lumbar Spine.

    PubMed

    Guan, Jian; Karsy, Michael; Schmidt, Meic H; Bisson, Erica F

    2015-10-01

    Study Design Retrospective case series. Objective Recent studies suggest that baseline hematocrit (Hct) levels may affect the surgical outcomes after orthopedic procedures. The authors examined whether preoperative Hct values had a significant effect on the hospital length of stay (LoS) after lumbar spinal procedures. Methods We retrospectively reviewed patients who underwent routine lumbar spine procedures from November 2012 through September 2013. Patients were included if they had both a baseline Hct and hospital LoS recorded. Patients were divided into two groups: those with an Hct ≥ 40% (nonanemic) and those with an Hct < 40% (anemic). LoS after surgery was evaluated for each group. Results One hundred seventeen patients underwent lumbar spine procedures for lumbar stenosis (n = 34), symptomatic lumbar disk herniation (n = 39), lumbar spondylolisthesis (n = 26), lumbar adjacent segment disease (n = 8), or symptomatic recurrent lumbar disk herniation (n = 10). Mean LoS was 3.3 and 2.4 days in anemic (27 patients) and nonanemic groups (90 patients), respectively (p = 0.02). The linear regression analysis demonstrated that a decrease in Hct was associated with a longer stay. A decrease from preoperative to postoperative day 1 Hct of 3.5 points resulted in an increased LoS of 1 day (R (2) = 0.145; p = 0.002). The correlation of Hct decrease with longer LoS remained (β = 0.167, p = 0.006) after adjusting for other variables with multivariate regression analysis. Conclusions Lower preoperative Hct or a substantial decrease in Hct may contribute to longer hospitalization after lumbar spine surgery. These findings should prompt an investigation into the strategies for optimizing Hct levels in patients with preoperative anemia prior to lumbar spine procedures. PMID:26430593

  6. Prevalence of Symptomatic Lumbar Spondylolysis in Pediatric Patients.

    PubMed

    Nitta, Akihiro; Sakai, Toshinori; Goda, Yuichiro; Takata, Yoichiro; Higashino, Kosaku; Sakamaki, Tadanori; Sairyo, Koichi

    2016-05-01

    Lumbar spondylolysis, a stress fracture of the pars interarticularis, is prevalent in adolescent athletes. Recent advances in diagnostic tools and techniques enable early diagnosis before these fractures progress to complete fractures through the pars. However, because patients often consult family physicians for primary care of low back pain and these physicians may not have access to diagnostic modalities such as magnetic resonance imaging (MRI) and computed tomography, stress fractures can be missed. This study surveyed the prevalence of symptomatic spondylolysis in pediatric patients who consulted an orthopedic clinic for primary care and investigated whether such acute stress fractures may be overlooked without MRI. The prospective study investigated 264 patients who were younger than 19 years and had low back pain. Of the 153 patients (58.0%) with low back pain persisting for longer than 2 weeks, 136 who agreed to undergo MRI were included in the study. This group included 11 elementary school students, 71 junior high school students, and 54 high school students. The overall prevalence of lumbar spondylolysis was 39.7% (54 of 136) and was 9.3% in elementary school students (5 of 11, 45.5%), 59.3% in junior high school students (32 of 71, 45.1%), and 31.5% in high school students (17 of 54, 31.5%). All 54 patients with spondylolysis had a history of athletic activity. Primary care physicians should recognize that approximately 40% of pediatric patients presenting with low back pain persisting for longer than 2 weeks may have spondylolysis and should consider MRI in those with a history of athletic activity. Because the spine is immature in this age group, almost half of affected elementary school and junior high school students may have lumbar spondylolysis. [Orthopedics. 2016; 39(3):e434-e437.]. PMID:27064777

  7. Facet joint changes after application of lumbar nonfusion dynamic stabilization.

    PubMed

    Lee, Soo Eon; Jahng, Tae-Ahn; Kim, Hyun Jib

    2016-01-01

    OBJECTIVE The long-term effects on adjacent-segment pathology after nonfusion dynamic stabilization is unclear, and, in particular, changes at the adjacent facet joints have not been reported in a clinical study. This study aims to compare changes in the adjacent facet joints after lumbar spinal surgery. METHODS Patients who underwent monosegmental surgery at L4-5 with nonfusion dynamic stabilization using the Dynesys system (Dynesys group) or transforaminal lumbar interbody fusion with pedicle screw fixation (fusion group) were retrospectively compared. Facet joint degeneration was evaluated at each segment using the CT grading system. RESULTS The Dynesys group included 15 patients, while the fusion group included 22 patients. The preoperative facet joint degeneration CT grades were not different between the 2 groups. Compared with the preoperative CT grades, 1 side of the facet joints at L3-4 and L4-5 had significantly more degeneration in the Dynesys group. In the fusion group, significant facet joint degeneration developed on both sides at L2-3, L3-4, and L5-S1. The subjective back and leg pain scores were not different between the 2 groups during follow-up, but functional outcome based on the Oswestry Disability Index improved less in the fusion group than in the Dynesys group. CONCLUSIONS Nonfusion dynamic stabilization using the Dynesys system had a greater preventative effect on facet joint degeneration in comparison with that obtained using fusion surgery. The Dynesys system, however, resulted in facet joint degeneration at the instrumented segments and above. An improved physiological nonfusion dynamic stabilization system for lumbar spinal surgery should be developed.

  8. Morphological and electrophysiological properties of cat lumbar paravertebral neurones.

    PubMed

    Percy, W H; Walsh, J; Krier, J

    1988-10-01

    The morphological and electrophysiological properties of neurones in the 3rd, 4th and 5th cat lumbar paravertebral ganglia were studied in vitro utilising intracellular injection of horseradish peroxidase (HRP) and intracellular electrophysiological recording techniques. Projections of neurones (T13-L5) were determined by in vivo HRP techniques. Two distinct soma morphologies were noted in all ganglia. Those whose long and short axes were approximately equal in length were designated as being 'spherical' and had a mean cross sectional area of 730 micron2. The remainder, whose long axis was at least 1.5 times the length of their short axis were called 'fusiform' and had a mean soma area of 540 micron2. The two cell types occurred in an approximate 2:1 ratio, respectively. The mean numbers of primary, secondary and tertiary dendrites for the population studied were 6.5, 6.3 and 3.4, respectively. Spherical cells had significantly more of each than fusiform cells as well as having a greater number of branch points and overall length of dendritic arbor. Neither cell type could be distinguished from the other based on the estimated number of fast excitatory postsynaptic potentials, the duration of the afterspike hyperpolarization or the duration of action potential discharge in response to 8-10-s depolarizing current pulses. The estimated number of synaptic potentials associated with both types of neurones (mean 10.6 +/- 1.6) correlated inversely only with the soma diameters (see Materials and Methods). It is concluded that while cat lumbar paravertebral neuronal soma may be classified into two morphologically distinct types, this is not reflected in their electrophysiological profiles. In addition, these data suggest that cat lumbar paravertebral neurones have a dendritic appearance and a degree of convergence of synaptic input previously shown to occur in this system. PMID:3209804

  9. Surgical vs Nonoperative Treatment for Lumbar Disk Herniation

    PubMed Central

    Weinstein, James N.; Tosteson, Tor D.; Lurie, Jon D.; Tosteson, Anna N. A.; Hanscom, Brett; Skinner, Jonathan S.; Abdu, William A.; Hilibrand, Alan S.; Boden, Scott D.; Deyo, Richard A.

    2008-01-01

    Context Lumbar diskectomy is the most common surgical procedure performed for back and leg symptoms in US patients, but the efficacy of the procedure relative to nonoperative care remains controversial. Objective To assess the efficacy of surgery for lumbar intervertebral disk herniation. Design, Setting, and Patients The Spine Patient Outcomes Research Trial, a randomized clinical trial enrolling patients between March 2000 and November 2004 from 13 multidisciplinary spine clinics in 11 US states. Patients were 501 surgical candidates (mean age, 42 years; 42% women) with imaging-confirmed lumbar intervertebral disk herniation and persistent signs and symptoms of radiculopathy for at least 6 weeks. Interventions Standard open diskectomy vs nonoperative treatment individualized to the patient. Main Outcome Measures Primary outcomes were changes from baseline for the Medical Outcomes Study 36-item Short-Form Health Survey bodily pain and physical function scales and the modified Oswestry Disability Index (American Academy of Orthopaedic Surgeons MODEMS version) at 6 weeks, 3 months, 6 months, and 1 and 2 years from enrollment. Secondary outcomes included sciatica severity as measured by the Sciatica Bothersomeness Index, satisfaction with symptoms, self-reported improvement, and employment status. Results Adherence to assigned treatment was limited: 50% of patients assigned to surgery received surgery within 3 months of enrollment, while 30% of those assigned to nonoperative treatment received surgery in the same period. Intent-to-treat analyses demonstrated substantial improvements for all primary and secondary outcomes in both treatment groups. Between-group differences in improvements were consistently in favor of surgery for all periods but were small and not statistically significant for the primary outcomes. Conclusions Patients in both the surgery and the nonoperative treatment groups improved substantially over a 2-year period. Because of the large numbers of

  10. Outcomes after incidental durotomy during first-time lumbar discectomy

    PubMed Central

    Desai, Atman; Ball, Perry A.; Bekelis, Kimon; Lurie, Jon; Mirza, Sohail K.; Tosteson, Tor D.; Weinstein, James N.

    2015-01-01

    Introduction Incidental durotomy is an infrequent but well-recognized complication during lumbar disc surgery. The effect of a durotomy on long-term outcomes is however, controversial. We sought to examine whether the occurrence of durotomy during surgery impacts long-term clinical outcome. Methods Spine Patient Outcomes Research Trial (SPORT) cohort participants with a confirmed diagnosis of intervertebral disc herniation (IDH) undergoing standard first-time open discectomy were followed from baseline at 6 weeks, 3, 6, and 12 months, and yearly thereafter, at 13 spine clinics in 11 US states. Patient data from this prospectively gathered database was reviewed. As of May 2009, the mean (SD) follow-up among all analyzed IDH patients was 41.5 (14.5) months (No durotomy: 41.4 vs. Had durotomy: 40.2, p-value<0.68). The median (range) follow-up time among all analyzed IDH patients was 47 (1 to 95) months. Results 799 patients underwent first-time lumbar discectomy. There was an incidental durotomy in 25 (3.1%) of these patients. There were no significant differences with or without durotomy in age, sex, race, body mass index, the prevalence of smoking, diabetes, hypertension, or herniation level or type. When outcome differences between the groups were analyzed, the durotomy group was found to have significantly increased operative duration, operative blood loss and inpatient stay. However, there were no differences in incidence of nerve root injury, post-op mortality, additional surgeries or SF-36 scores of bodily pain or physical function, or Oswestry Disability Index at 1, 2, 3 or 4 years. Conclusions Incidental durotomy during first time lumbar discectomy does not appear to impact long-term outcome in affected patients. PMID:21375385

  11. The effects of transcutaneous neuromuscular electrical stimulation on the activation of deep lumbar stabilizing muscles of patients with lumbar degenerative kyphosis.

    PubMed

    Kim, So Yeon; Kim, Jin Hyun; Jung, Gil Su; Baek, Seung Ok; Jones, Rodney; Ahn, Sang Ho

    2016-01-01

    [Purpose] To investigate the effectiveness of three different neuromuscular electrical stimulation (NMES) protocols for the deep lumbar stabilizing muscles of patients with lumbar degenerative kyphosis (LDK). [Subjects and Methods] Twenty patients with LDK were recruited. Three stimulation protocols were investigated: stimulation of the abdominal muscles (protocol A); stimulation of the lumbar muscles (protocol B); and simultaneous stimulation of the abdominal and lumbar muscles (protocol A+B). Images of the obliquus externus (OE), obliquus internus (OI), transversus abdominis (TrA), and lumbar multifidus (LM) muscles were captured by real-time ultrasound imaging (RUSI). [Results] The thickness of LM was significantly greater during stimulation than at rest for all three protocols. Thicknesses of the abdominal muscles (TrA, OI, and OE) were significantly greater during stimulation than at rest for protocols A and A+B. Thickness increases in LM were significantly greater during protocols B and A+B, but not during protocol A. Thickness increases in the abdominal muscles (TrA, OI, and OE) were significantly greater during protocols A and A+B, but not during protocol B. [Conclusion] NMES can significantly activate the deep lumbar stabilizing muscles of patients with LDK. Protocol A+B of NMES is recommended to aid postural correction and low back pain (LBP) in patients with LDK. PMID:27064323

  12. The effects of transcutaneous neuromuscular electrical stimulation on the activation of deep lumbar stabilizing muscles of patients with lumbar degenerative kyphosis

    PubMed Central

    Kim, So Yeon; Kim, Jin Hyun; Jung, Gil Su; Baek, Seung Ok; Jones, Rodney; Ahn, Sang Ho

    2016-01-01

    [Purpose] To investigate the effectiveness of three different neuromuscular electrical stimulation (NMES) protocols for the deep lumbar stabilizing muscles of patients with lumbar degenerative kyphosis (LDK). [Subjects and Methods] Twenty patients with LDK were recruited. Three stimulation protocols were investigated: stimulation of the abdominal muscles (protocol A); stimulation of the lumbar muscles (protocol B); and simultaneous stimulation of the abdominal and lumbar muscles (protocol A+B). Images of the obliquus externus (OE), obliquus internus (OI), transversus abdominis (TrA), and lumbar multifidus (LM) muscles were captured by real-time ultrasound imaging (RUSI). [Results] The thickness of LM was significantly greater during stimulation than at rest for all three protocols. Thicknesses of the abdominal muscles (TrA, OI, and OE) were significantly greater during stimulation than at rest for protocols A and A+B. Thickness increases in LM were significantly greater during protocols B and A+B, but not during protocol A. Thickness increases in the abdominal muscles (TrA, OI, and OE) were significantly greater during protocols A and A+B, but not during protocol B. [Conclusion] NMES can significantly activate the deep lumbar stabilizing muscles of patients with LDK. Protocol A+B of NMES is recommended to aid postural correction and low back pain (LBP) in patients with LDK. PMID:27064323

  13. Hysterical conversion paralysis in an adolescent boy with lumbar spondylolysis.

    PubMed

    Higuchi, Tadahiro; Tonogai, Ichiro; Sakai, Toshinori; Takata, Yoichiro; Goda, Yuichiro; Abe, Mitsunobu; Jha, Subash C; Fukuta, Shoji; Higashino, Kosaku; Nagamachi, Akihiro; Sairyo, Koichi

    2016-05-01

    We describe a case of recurrent hysterical paralysis triggered by low back pain because of lumbar spondylolysis. A 16-year-old male soccer player was referred to our institution with five previous episodes of acute paralysis triggered by severe low back pain. We performed direct surgical repair of the terminal-stage bilateral spondylolysis at L4 using a hook-rod system. His chronic low back pain was completely resolved, and no further episodes of hysterical paralysis have occurred after surgery. Spine surgeons should be aware of possible hysterical conversion paralysis when there is discrepancy between radiological and neurological findings. PMID:26049966

  14. Post-Lumbar Puncture Headache Etiology and Management

    PubMed Central

    Raymond, John R.; Raymond, Patrick A.

    1988-01-01

    Headache following a lumbar puncture is a common and often debilitating syndrome. Continued leakage of cerebrospinal fluid from a puncture site decreases intracranial pressure, which leads to traction on pain-sensitive intracranial structures. The headache is characteristically postural, often associated with nausea and optic, vestibular, or otic symptoms. Although usually self-limited after a few days, severe postural pain can incapacitate the patient. Management is mainly symptomatic, but definitive treatment with the epidural blood patching technique is safe and effective when done by an expert operator. PMID:3176458

  15. The management of pain following laminectomy for lumbar disc lesions.

    PubMed Central

    Martin, G.

    1981-01-01

    Assessment of the results of laminectomy for lumbar disc lesions is unsatisfactory, but it seems that some degree of recurrent pain is virtually inevitable. The clinical features and incidence of the various painful syndromes seen in these patients, including one, the sacro-spinalis insertion syndrome, which has not previously been described, are outlined and the management of each is discussed with reference to two personal series, one of 98 patients consecutively undergoing laminectomy and the other of 35 patients referred because of recurrent pain following laminectomy. Finally, problems of prophylaxis are considered. PMID:6454375

  16. Management of severe pain due to lumbar disk protrusion.

    PubMed

    Conroy, Liam

    2015-03-01

    Lumbar intervertebral disk protrusion can cause excruciating pain in severe cases, which can be exacerbated by activity such as sitting down and straining at stool. Acute sciatica due to disk rupture will improve within 1 to 3 months. The efficacy of drugs used for the management of sciatica in primary care is unclear. Severe cases can require opioid analgesia, however people taking opioids for pain relief frequently present with opioid-induced bowel dysfunction. The use of transforaminal steroid injections is a controversial issue and repeat steroid injections should be considered in light of the risk-benefit profile of the individual patient. PMID:25643230

  17. [Lumbar endoscopy: analysis and evaluation of 10 primary operations].

    PubMed

    Guillonneau, B; Vallancien, G; Veillon, B; Brisset, J M

    1995-02-01

    The authors report their experience of the first 10 patients operated by upper urinary tract lumboscopic surgery. Lumboscopy is performed in the lateral supine position and a simple technique for creation of retropneumoritoneum is described. In 4 patients, the planned nephrectomy could be performed because of poor anatomical conditions (peripyelitis and/or perinephritis). Lumboscopy allowed complete renal exploration, two nephrectomies, two resections of the roofs of compressive parapelvic cysts and one lumbar ureterolithotomy. The ease and rapidity of lumboscopic dissection makes it a valuable alternative to laparoscopy.

  18. Interobserver discrepancies in distance measurements from lumbar spine CT scans

    SciTech Connect

    Beers, G.J.; Carter, A.P.; Leiter, B.E.; Tilak, S.P.; Shah, R.R.

    1985-02-01

    Lumbar spine computed tomographic (CT) scans of 10 patients were examined independently at two levels by five experienced radiologists. At each level the minimum midline sagittal diameter was measured, and at each intervertebral space the left foramen was measured for its minimum diameter. Statistically significant differences were found between the measurements of different observers, differences that in a number of cases could have led to disagreement over whether or not stenosis was present. There were reasonably strong correlations between different observers' readings of midline sagittal diameters but generally not of foraminal diameters. Reasons for discrepancies between observers in spine CT measurements are reviewed briefly.

  19. Alkaptonuria and lumbar disc herniation. Report of three cases.

    PubMed

    Farzannia, Akbar; Shokouhi, Ghaffar; Hadidchi, Shahram

    2003-01-01

    Alkaptonuria is a rare metabolic disease caused by deficiency of homogentisic acid oxidase and characterized by bluish-black discoloration of cartilages and skin (ochronosis). The authors report the cases of three patients with lumbar disc herniation who underwent discectomy and in whom the nucleus pulposus was discovered to be black. Alkaptonuria was diagnosed after discectomy. Discal herniation requiring surgery is unusual in alkaptonuria, with only a few reports. The symptoms in the three patients disappeared after surgery and no symptoms were demonstrated on follow-up examination. PMID:12546396

  20. Haemorrhagic Lumbar Juxtafacet Cyst with Ligamentum Flavum Involvement

    PubMed Central

    Ghent, Finn; Davidson, Trent; Mobbs, Ralph Jasper

    2014-01-01

    Juxtafacet cysts are an uncommon cause of radiculopathy. They occur most frequently in the lumbar region, and their distribution across the spine correlates with mobility. Haemorrhagic complications are rare and may occur in the absence of any provocation, although there is some association with anticoagulation and trauma. We present a case of acute radiculopathy due to an L5/S1 juxtafacet cyst with unprovoked haemorrhage which was found to extend into ligamentum flavum. The patient underwent uncomplicated microscope assisted decompression with excellent results. The demographics, presentation, aetiology, and management of juxtafacet cysts are discussed. PMID:25580330