1,135 research outputs found
Outcomes of Fusions From the Cervical Spine to the Pelvis.
Study designRetrospective cohort study.ObjectiveDetermine the indications, complications, and clinical outcomes in patients requiring fusions from the cervical spine to the pelvis. Several investigators have examined fusions from the thoracic spine to the sacrum, but no similar study has been performed for cervical-to-pelvis fusions.MethodsPatients from 2003 to 2014 with an upper instrumented vertebrae (UIV) in the cervical spine (any level) and a lower instrumented vertebrae (LIV) in the sacrum or pelvis were included in the study. Those with infectious or acute trauma-related deformities were excluded. Patient demographics, medical history, diagnosis, operative procedure, and health-related quality of life measures were analyzed. Student's t test, Kruskal-Wallis test, and χ2 test were used as appropriate; significance was set at P < .05 for all tests.ResultsFifty-five patients met inclusion criteria for the study. Average follow-up was 2.8 years. Proximal junctional kyphosis was the most common indication for cervical-to-pelvis fusions (36%). The most common UIV was C2 (29%) followed by C7 (24%). There was an average 31° correction in maximum kyphosis and a 3.3 cm improvement in sagittal vertical axis. In adults, the rate of complication was 71.4%, with a major complication rate of 39.3% and reoperation rate of 53.6%. There was significant improvement in the Scoliosis Research Society (SRS-22r) score (3.0 to 3.5; P < .01).ConclusionProximal junctional kyphosis is the most common indication for patients requiring fusion to the cervical spine. Adult patients incur a significant risk of major complications and reoperations. However, significant improvement in SRS-22r outcomes are noted in these patients
Clinical Pathological Analysis of Surgically Resected Superficial Esophageal Carcinoma to Determine Criteria for Deciding on Treatment Strategy
We performed a clinical pathological study of conventionally resected superficial esophageal carcinomas since this type of lesion has been increasing, in order to develop criteria of determination for therapeutic strategies. Pathological studies were performed on specimens obtained by radical surgical resection in 133 cases of superficial esophageal cancer. Evaluation was performed in terms of the gross classification of the lesion type, depth of invasion, lymph node metastasis, vascular invasion, size of the lesion, outcome, etc. In 0-I, 0-IIc+0-IIa, and 0-III type submucosal cancer lesions the rate of metastasis to lymph nodes was more than 40%, but in 0-IIa and 0-IIb mucosal cancer cases no lymph node metastasis was observed. 0-IIc type lesions showed a wide range of invasiveness, ranging from m1 to sm3. In cases with m1 or m2 invasion, no lymph node or lymph-vessel invasion was recognized, but in m3, sm1, sm2, and sm3 cases lymph node metastasis was recognized in 12.5%, 22.2%, 44.0% and 47.4%, respectively. In 47% of lesions with a greatest dimension of less than 30 mm invasion was limited to the mucosa. Seventy-two percent of m1 and m2 cases were 30 mm in size or less. Lymph node metastasis was recognized in only 16.7% of cases less than 30 mm in size, but in cases of lesions 30 mm or more the rate of lymph node metastasis was 35.8%. 0-IIb and 0-IIa type lesions are indications for endoscopic esophageal mucosal resection (EEMR), while 0-I, 0-IIc+0-IIa, and 0-III lesions should be candidates for radical surgical resection. In the 0-IIc category, lesions in which the depression is relatively flat and with a finely granular surface are indications for EEMR, but those cases in which the surface of depression shows granules of varying sizes should be treated with radical surgical resection. Cases of 0-IIa type 30 mm or larger in greatest dimension which have a gently sloping protruding margin shoulder or reddening should be treated with caution, but EEMR can be performed first and subsequent therapeutic strategy decided on, based on the pathological findings of the specimen
The Effect of Military Load Carriage on Postural Sway, Forward Trunk Lean, and Pelvic Girdle Motion
International Journal of Exercise Science 10(1): 25-36, 2017. Musculoskeletal injuries are a common occurrence in military service members. It is believed that the load carried by the service member impedes stability and alters back and pelvis kinematics, increasing their susceptibility to musculoskeletal injuries, specifically in the lower extremities. The purpose of this study was to examine the effects of two different loads on postural sway, forward trunk lean, and pelvic girdle motion in United States Army Cadets. Twenty male Army Reserve Officers’ Training Corps Cadets participated in this study. Each participant performed the Modified Clinical Testing of Sensory Interaction (mCTSIB) Protocol and the Unilateral Stance (ULS) Protocol under three different rucksack load conditions (unloaded, 16.0 kg, and 20.5 kg loads). Mean postural sway velocity was recorded along with 2-D kinematics of the trunk in the sagittal plane and the pelvis in the frontal and sagittal planes. External loads of 16.0 kg (p \u3c 0.001) and 20.5 kg (p ≤ 0.003) significantly increased mean sway velocity by 16% to 52% depending on stance and visual condition, but did not produce significant changes in trunk and pelvic kinematics
Power-law distributions and Levy-stable intermittent fluctuations in stochastic systems of many autocatalytic elements
A generic model of stochastic autocatalytic dynamics with many degrees of
freedom is studied using computer simulations. The time
evolution of the 's combines a random multiplicative dynamics at the individual level with a global coupling through a
constraint which does not allow the 's to fall below a lower cutoff given
by , where is their momentary average and is a
constant. The dynamic variables are found to exhibit a power-law
distribution of the form . The exponent
is quite insensitive to the distribution of the random factor
, but it is non-universal, and increases monotonically as a function
of . The "thermodynamic" limit, N goes to infty and the limit of decoupled
free multiplicative random walks c goes to 0, do not commute:
for any finite while (which is the common range
in empirical systems) for any positive . The time evolution of exhibits intermittent fluctuations parametrized by a (truncated)
L\'evy-stable distribution with the same index . This
non-trivial relation between the distribution of the 's at a given time
and the temporal fluctuations of their average is examined and its relevance to
empirical systems is discussed.Comment: 7 pages, 4 figure
Determination of the pion-nucleon coupling constant and scattering lengths
We critically evaluate the isovector GMO sum rule for forward pion-nucleon
scattering using the recent precision measurements of negatively charged
pion-proton and pion-deuteron scattering lengths from pionic atoms. We deduce
the charged-pion-nucleon coupling constant, with careful attention to
systematic and statistical uncertainties. This determination gives, directly
from data a pseudoscalar coupling constant of
14.11+-0.05(statistical)+-0.19(systematic) or a pseudovector one of 0.0783(11).
This value is intermediate between that of indirect methods and the direct
determination from backward neutron-proton differential scattering cross
sections. We also use the pionic atom data to deduce the coherent symmetric and
antisymmetric sums of the negatively charged pion-proton and pion-neutron
scattering lengths with high precision. The symmetric sum gives
0.0012+-0.0002(statistical)+-0.0008 (systematic) and the antisymmetric one
0.0895+-0.0003(statistical)+-0.0013(systematic), both in units of inverse
charged pion-mass. For the need of the present analysis, we improve the
theoretical description of the pion-deuteron scattering length.Comment: 27 pages, 5 figures, submitted to Phys. Rev. C, few modifications and
clarifications, no change in substance of the pape
A spectroscopic survey of thick disc stars outside the solar neighbourhood
We performed a spectroscopic survey of nearly 700 stars probing the galactic
thick disc far from the solar neighbourhood towards the galactic coordinates
(l~277, b~47). The derived effective temperatures, surface gravities and
overall metallicities were then combined with stellar evolution isochrones,
radial velocities and proper motions to derive the distances, kinematics and
orbital parameters of the sample stars. The targets belonging to each galactic
component (thin disc, thick disc, halo) were selected either on their
kinematics or according to their position above the galactic plane, and the
vertical gradients were also estimated. We present here atmospheric parameters,
distances and kinematics for this sample, and a comparison of our kinematic and
metallicity distributions with the Besancon model of the Milky Way. The thick
disc far from the solar neighbourhood is found to differ only slightly from the
thick disc properties as derived in the solar vicinity. For regions where the
thick disc dominates, we measured vertical velocity and metallicity trends of
d(V_phi)/dZ = 19 +/- 8 km/s/kpc and d[M/H]/dZ = -0.14 +/- 0.05 dex/kpc,
respectively. These trends can be explained as a smooth transition between the
different galactic components, although intrinsic gradients could not be
excluded. In addition, a correlation d(V_phi)/d[M/H] = -45 +/- 12 km/s/dex
between the orbital velocity and the metallicity of the thick disc is detected.
This gradient is inconsistent with the SDSS photometric survey analysis, which
did not detect any such trend, and challenges radial migration models of thick
disc formation. Estimations of the scale heights and scale lengths for
different metallicity bins of the thick disc result in consistent values, with
hR~3.4 \pm 0.7 kpc, and hZ~694 \pm 45 pc, showing no evidence of relics of
destroyed massive satellites.Comment: 19 pages, 15 figures, accepted for publication in A&
Exclusive electroproduction of K+ Lambda and K+ Sigma^0 final states at Q^2 = 0.030-0.055 (GeV/c)^2
Cross section measurements of the exclusive p(e,e'K+)Lambda,Sigma^0
electroproduction reactions have been performed at the Mainz Microtron MAMI in
the A1 spectrometer facility using for the first time the Kaos spectrometer for
kaon detection. These processes were studied in a kinematical region not
covered by any previous experiment. The nucleon was probed in its third
resonance region with virtual photons of low four-momenta, Q^2= 0.030-0.055
(GeV/c)^2. The MAMI data indicate a smooth transition in Q^2 from
photoproduction to electroproduction cross sections. Comparison with
predictions of effective Lagrangian models based on the isobar approach reveal
that strong longitudinal couplings of the virtual photon to the N* resonances
can be excluded from these models.Comment: 16 pages, 7 figure
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