Transcarpal Motor Conduction Velocity: Repeatability and Application in Carpal Tunnel Syndrome.

Background: Conduction velocity of the short segment of the median motor nerve, across wrist (transcarpal motor conduction velocity (TCMCV)), has been used to increase diagnostic yield in carpal tunnel syndrome (CTS). However, repeatability of this parameter has not been studied till date. It has not been used as an indicator of response to treatment. Using surface stimulation techniques, it is difficult to localize the sites of stimulation of transcarpal segment of median nerve in palm. As a result, small errors in measurements of TCMCV can be magnified and variability of TCMCV may occur on successive measurements. Despite this possible variation, TCMCV can be a useful tool for assessing response to therapy, if its repeatability is assessed and a cut-off value determined for a significant change in nerve conduction velocity. Purpose: In this study, it was determined whether TCMCV is repeatable. If found to be repeatable, we show a method to determine the cut-off value of the change in this parameter for it to be considered significant. Methods: Difference between values of TCMCV on successive measurements was obtained in hands of 26 controls. Repeatability of this parameter was determined in this control population following criteria of British Standards Institution. In 19 patients of CTS, treated with intracarpal steroid injection, pre-treatment and post-treatment values of TCMCV, and of symptom severity scale (SSS) and functional status scale (FSS), were obtained at 1, 2, and 3 months after treatment. Results: Repeat measurements of TCMCV were made in each hand of all controls. After applying criteria of British Standards Institution, to such recordings, TCMCV was found to be repeatable and the cut-off value for significant change determined. According to this cut-off value, 4 patients of CTS showed improvement in TCMCV, with consistent improvement in SSS and FSS. Change in TCMCV corroborated qualitatively with changes in SSS and FSS. Conclusion: Repeatability of TCMCV can be assessed by criteria of British Standards Institution and a cut-off value determined to use it as an indicator of response to treatment in CTS.

Medial Patellofemoral Ligament Reconstruction: An Uncommon Solution for a Common Problem.

Patellofemoral dislocations are commonly encountered knee ailment. Although majority of the patients are managed conservatively, depending on the patients' demands and predisposing factors, patients with recurrent dislocations often require surgical intervention. The main aim of any surgical procedure should be to restore the anatomy of the soft tissue as well as the bony elements. We here describe a technique which combines transverse patella double tunnel technique with tibial tuberosity distalization and medicalization to reconstruct the medial patellofemoral ligament using a free autologous semitendinosus graft.

A Case Report of Bilateral Asymmetrical Traumatic Hip Dislocation - A Rare Presentation.

INTRODUCTION: Asymmetric bilateral hip dislocations are very rarely reported in literature. We report a unique case of asymmetric traumatic bilateral hip dislocation in a 34-year-old male, describing the management and post-operative complications. CASE REPORT: A 34-year-old truck driver sustained injury to both his hips in a head on collision between two trucks while seated in the passenger seat. There was a delay in presentation at our institution as he was referred after 17 h of the trauma. After evaluation, he underwent closed reduction of both hips under intravenous anesthesia on the same day. The post-reduction assessment revealed a left-sided posterior wall fracture which was suspected due to the instability after reduction. Fixation of the fracture was done using two spring plates. The patient was followed up throughout his rehabilitation and thereafter when he resumed his occupation. Six months after the incident, the patient had pain-free, full range of motion of both hips. Three years after the surgery radiological investigations revealed changes suggestive of early avascular necrosis (AVN), however, the patient did not have any functional restriction. CONCLUSION: This is a case of bilateral asymmetric hip dislocation with left side posterior wall fracture. It is important to reduce the hip and also address the fracture as early as possible to prevent AVN.

Single-pulse (100 ps) extended x-ray absorption fine structure capability at the Dynamic Compression Sector.

Determining real-time changes in the local atomistic order is important for a mechanistic understanding of shock wave induced structural and chemical changes. However, the single event and short duration (nanosecond times) nature of shock experiments pose challenges in obtaining Extended X-ray Absorption Fine Structure (EXAFS) measurements-typically used for monitoring local order changes. Here, we report on a new single pulse (∼100 ps duration) transmission geometry EXAFS capability for use in laser shock-compression experiments at the Dynamic Compression Sector (DCS), Advanced Photon Source. We used a flat plate of highly oriented pyrolytic graphite (HOPG) as the spectrometer element to energy disperse x rays transmitted through the sample. It provided high efficiency with ∼15% of the x rays incident on the HOPG reaching an x-ray area detector with high quantum efficiency. This combination resulted in a good signal-to-noise ratio (∼103), an energy resolution of ∼10 eV at 10 keV, EXAFS spectra covering 100 s of eV, and a good pulse to pulse reproducibility of our single pulse measurements. Ambient EXAFS spectra for Cu and Au are compared to the reference spectra, validating our measurement system. Comparison of single pulse EXAFS results for ambient and laser shocked Ge(100) shows large changes in the local structure of the short lived state of shocked Ge. The current DCS EXAFS capability can be used to perform single pulse measurements in laser shocked materials from ∼9 keV to 13 keV. These EXAFS developments will be available to all users of the DCS.

Collinear antiferromagnetism in trigonal SrMn2As2 revealed by single-crystal neutron diffraction.

Iron pnictides and related materials have been a topic of intense research for understanding the complex interplay between magnetism and superconductivity. Here we report on the magnetic structure of SrMn2As2 that crystallizes in a trigonal structure ([Formula: see text]) and undergoes an antiferromagnetic (AFM) transition at [Formula: see text] K. The magnetic susceptibility remains nearly constant at temperatures [Formula: see text] with [Formula: see text] whereas it decreases significantly with [Formula: see text]. This shows that the ordered Mn moments lie in the [Formula: see text] plane instead of aligning along the [Formula: see text]-axis as in tetragonal BaMn2As2. Single-crystal neutron diffraction measurements on SrMn2As2 demonstrate that the Mn moments are ordered in a collinear Néel AFM phase with [Formula: see text] AFM alignment between a moment and all nearest neighbor moments in the basal plane and also perpendicular to it. Moreover, quasi-two-dimensional AFM order is manifested in SrMn2As2 as evident from the temperature dependence of the order parameter.

Cardiovascular Autonomic Neuropathy in Systemic Lupus Erythematosus.

PURPOSE: Objective is to evaluate cardiovascular autonomic function in SLE by simple non-invasive tests. METHODS: A case control study was carried out involving 18-50 yrs old previously diagnosed SLE patients and same number of age and sex-matched controls. Parasympathetic function was assessed by heart rate (HR) response to Valsalva maneuver, deep breathing and standing. Sympathetic function was evaluated by blood pressure response to standing and sustained hand-grip test (HGT). RESULTS: There were 50 female SLE patients. They had significantly higher minimum resting HR and diastolic blood pressure (DBP). HR variation with deep breathing, expiratory inspiratory ratio, 30:15 ratio and DBP change in response to HGT were significantly lower inpatients compared to controls. Thirty patients (60%) had at least one abnormal or two borderline test results indicating autonomic impairment of which 27 had parasympathetic dysfunction and 7 had sympathetic dysfunction. CONCLUSION: Autonomic dysfunction is common in SLE with higher prevalence of parasympathetic impairment.

The valence-fluctuating ground state of plutonium.

A central issue in material science is to obtain understanding of the electronic correlations that control complex materials. Such electronic correlations frequently arise because of the competition of localized and itinerant electronic degrees of freedom. Although the respective limits of well-localized or entirely itinerant ground states are well understood, the intermediate regime that controls the functional properties of complex materials continues to challenge theoretical understanding. We have used neutron spectroscopy to investigate plutonium, which is a prototypical material at the brink between bonding and nonbonding configurations. Our study reveals that the ground state of plutonium is governed by valence fluctuations, that is, a quantum mechanical superposition of localized and itinerant electronic configurations as recently predicted by dynamical mean field theory. Our results not only resolve the long-standing controversy between experiment and theory on plutonium's magnetism but also suggest an improved understanding of the effects of such electronic dichotomy in complex materials.

Magnitude of the magnetic exchange interaction in the heavy-fermion antiferromagnet CeRhIn5.

We have used high-resolution neutron spectroscopy experiments to determine the complete spin wave spectrum of the heavy-fermion antiferromagnet CeRhIn5. The spin wave dispersion can be quantitatively reproduced with a simple frustrated J1-J2 model that also naturally explains the magnetic spin-spiral ground state of CeRhIn5 and yields a dominant in-plane nearest-neighbor magnetic exchange constant J0=0.74(3) meV. Our results pave the way to a quantitative understanding of the rich low-temperature phase diagram of the prominent CeTIn5 (T=Co, Rh, Ir) class of heavy-fermion materials.

Image guidance in prostate cancer - can offline corrections be an effective substitute for daily online imaging?

PURPOSE: This aim of this study was to determine if a less resource-intensive and established offline correction protocol - the No Action Level (NAL) protocol was as effective as daily online corrections of setup deviations in curative high-dose radiotherapy of prostate cancer. MATERIALS AND METHODS: A total of 683 daily megavoltage CT (MVCT) or kilovoltage CT (kvCBCT) images of 30 patients with localized prostate cancer treated with intensity modulated radiotherapy were evaluated. Daily image-guidance was performed and setup errors in three translational axes recorded. The NAL protocol was simulated by using the mean shift calculated from the first five fractions and implemented on all subsequent treatments. Using the imaging data from the remaining fractions, the daily residual error (RE) was determined. The proportion of fractions where the RE was greater than 3,5 and 7 mm was calculated, and also the actual PTV margin that would be required if the offline protocol was followed. RESULTS: Using the NAL protocol reduced the systematic but not the random errors. Corrections made using the NAL protocol resulted in small and acceptable RE in the mediolateral (ML) and superoinferior (SI) directions with 46/533 (8.1%) and 48/533 (5%) residual shifts above 5 mm. However; residual errors greater than 5mm in the anteroposterior (AP) direction remained in 181/533 (34%) of fractions. The PTV margins calculated based on residual errors were 5mm, 5mm and 13 mm in the ML, SI and AP directions respectively. CONCLUSION: Offline correction using the NAL protocol resulted in unacceptably high residual errors in the AP direction, due to random uncertainties of rectal and bladder filling. Daily online imaging and corrections remain the standard image guidance policy for highly conformal radiotherapy of prostate cancer.