Sudakov resummation of multiparton QCD cross sections

We present the general expressions for the resummation, up to next-to-leading logarithmic accuracy, of Sudakov-type logarithms in processes with an arbirtrary number of hard-scattering partons. These results document the formulae used by the authors in several previous phenomenological studies. The resummation formulae presented here, which are valid for phase-space factorizable observables, determine the resummation correction in a process-independent fashion. All process dependence is encoded in the colour and flavour structure of the leading order and virtual one-loop amplitudes, and in Sudakov weights associated to the cross section kinematics. We explicitly illustrate the application to the case of Drell--Yan and prompt-photon production.Comment: 13 pages, LaTe

The qTq_T subtraction method for top quark production at hadron colliders

We consider QCD radiative corrections to top-quark pair production at hadron colliders. We use the $q_T$ subtraction formalism to perform a fully-differential computation for this process. Our calculation is accurate up to the next-to-leading order in QCD perturbation theory and it includes all the flavour off-diagonal partonic channels at the next-to-next-to-leading order. We present a comparison of our numerical results with those obtained with the publicly available numerical programs MCFM and Top++.Comment: Few references and comments added, expanded discussion on the qt subtraction method, result unchanged, version published in EPJ

QCD corrections to e+e−→u dˉ s cˉe^+ e^- \to u~\bar d~s~\bar c at Lep 2 and the Next Linear Collider: CC11 at O(\alpha_s)

QCD one-loop corrections to the full gauge invariant set of electroweak diagrams describing the hadronic process $e^+ e^- \to u~\bar d~s~\bar c$ are computed. Four-jet shape variables for $WW$ events are studied at next-to-leading order and the effects of QCD corrections on the determination of the $W$--mass in the hadronic channel at Lep 2 and NLC is discussed. We compare the exact calculation with a ``naive''approach to strong radiative corrections which has been widely used in the literature.Comment: 10 pages, 4 ps figures, requires axodra

A new volar plate DiPhos-RM for fixation of distal radius fracture: Preliminary report

We analyzed the efficiency of a new plate DiPhos-RM in CFR-PEEK [carbon-fiber-reinforced poly (etheretherketone)] for the volar fixation of distal radius fractures. The new plate's composition has the advantage of x-ray absolute transparency, therefore allowing to monitor the healing of the fracture. The desired combination of high strength and low rigidity is obtained through the use of the polymer composites CFR-PEEK. In this preliminary study (from March 2012 to June 2012), 10 cases of intra-articular distal radius fractures were treated with DiPhos-RM produced by Lima Corporate (Italy). The fractures were classified according to the AO classification, 4 fractures were type C1, 3 type C2, and 3 were A2. A preoperative computed tomography scan was carried out in all patients. One patient also underwent a postoperative computed tomography scan. Grip strength, range of motion, and DASH score were evaluated at follow-up. There were no cases of hardware failure. Specifically, no loss of position or alignment of fixed-angle locking screws or breakage of the plate were observed. Radiographic union was present at an average of 6 weeks (range, 5 to 8 wk). The overall preliminary experience with this new plate is favorable. The new plate is easy to apply and provides the surgeon dual options of fixed-angle or variable-angle screws. It was rigid enough to maintain the reduction also in AO type C articular fractures. Copyright © 2013 by Lippincott Williams & Wilkins

Malunited extra-articular distal radius fractures: corrective osteotomies using volar locking plate

Background: Multiple techniques for corrective osteotomy have been developed in recent years with the same aims: to improve the radiographic parameters and improve motion, pain and grip strength. Volar fixed-angle plates have added a new concept to the treatment of distal radius fractures thanks to the low morbidity of the surgical approach and the strength of the final construct, allowing early mobilization and return to function.Materials and methods: Between 2005 and 2012, 20 patients with symptomatic dorsally malunited extra-articular fractures of the distal radius underwent corrective osteotomy using a volar locking plate without additional bone graft. At a mean follow-up of 50 months, all the patients were clinically and functionally evaluated.Results: All measurements of pain, final range of motion and grip strength significantly improved compared with preoperative measurements. The mean preoperative DASH score reduced from 54 points preoperatively to 25 postoperatively. Based on the modified Mayo wrist score, we obtained 14 excellent and six good results. Palmar tilt improved from an average of 23° to 11°. Radial inclination improved from an average of 29° to 22°, and ulnar variance decreased from an average of 3.6 mm to 0.9 mm. There were two cases of transient median neuroapraxia that resolved before the 6-week follow-up appointment. No other major complications, including non-union and infection, were observed.Conclusion: The volar approach and locking plate, without necessarily the use of bone grafting, proved to be an effective approach for addressing symptomatic and even severe deformities of the distal radius.Type of study/level of evidence: Therapeutic IV

Treatment of the ulna non-unions using dynamic compression plate fixation, iliac bone grafting and autologous platelet concentrate

Clinical study of a series of ten patients treated between 2004 and 2009 for non-unions of the ulna. The patients have been treated with osteosynthesis using a dynamic compression plate and biological enhancement of the consolidation using bone graft and autologous platelet injection. The follow-up consisted of clinical and radiographic assessment. Functional scores used were the Visual Analogue Scale (VAS) for pain and the Disability Assessment for the Shoulder and Hand (DASH) questionnaire. The mean time of follow-up was 21 months. Considering both clinical and radiological criteria, bony union was achieved in 9/10 cases on average time of 4 months. According to the system of Anderson, 5 patients provided an excellent result, 2 a satisfactory result, 2 an unsatisfactory result and 1 treatment resulted in failure. At follow-up, the mean VAS score for pain in the upper limb was 1 (range, 0-4) at rest and 2 (range, 0-7) during activities. The physical function and symptoms of the upper limb, evaluated with the DASH questionnaire, scored 17 points. In conclusion, at a mean 21 months follow-up, there was high success regarding both forearm alignment, clinical and functional results. The use of three combined methods provides high success regarding both radiological and clinical results, even if we have no information on the prevalent efficacy of one particular method. © Springer-Verlag 2011

A new volar plate made of carbon-fiber-reinforced polyetheretherketon for distal radius fracture: analysis of 40 cases

BACKGROUND: Implants based on the polyetheretherketon (PEEK) polymer have been developed in the last decade as an alternative to conventional metallic devices. PEEK devices may provide several advantages over the use of conventional orthopedic materials, including the lack of metal allergies, radiolucency, low artifacts on magnetic resonance imaging scans and the possibility of tailoring mechanical properties. The purpose of this study was to evaluate the clinical results at 12-month follow-up using a new plate made of carbon-fiber-reinforced polyetheretherketon for the treatment of distal radius fractures. MATERIALS AND METHODS: We included 40 consecutive fractures of AO types B and C that remained displaced after an initial attempt at reduction. The fractures were classified according to the AO classification: 21 fractures were type C1, 9 were type C2, 2 were type C3, 2 were type B1 and 6 were type B2. RESULTS: At a 12-month follow-up no cases of hardware breakage or loss of the surgically achieved fracture reduction were documented. All fractures healed, and radiographic union was observed at an average of 6 weeks. The final Disabilities of Arm, Shoulder and Hand score was 6.0 points. The average grip strength, expressed as a percentage of the contralateral limb, was 92 %. Hardware removal was performed only in one case, for the occurrence of extensor tenosynovitis. CONCLUSION: At early follow-up this device showed good clinical results and allowed maintenance of reduction in complex, AO fractures. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV

Volar plate fixation for the treatment of distal radius fractures: Analysis of adverse events

OBJECTIVES:: Determining the rate of specific adverse events after volar plating performed for distal radius fractures. DESIGN:: Retrospective. SETTING:: University level I trauma center. PATIENTS:: We searched the electronic database of all surgical procedures performed in our department using the following keywords: distal radius fracture, wrist fracture, and plate fixation. We identified 315 patients, 12 of whom were lost at follow-up. INTERVENTION:: Volar plate fixation for the treatment of distal radius fractures. MAIN OUTCOME MEASUREMENTS:: At an average follow-up of 5 years, 303 patients were evaluated through medical records and clinical and radiographic assessment for specific adverse events after volar plate fixation. RESULTS:: Adverse events were observed in 18 patients (5.9%). Implant-related adverse events, including tendon impairments, intra-articular screws, and screw loosening, were observed in 15 patients (5.0%). Extensor tendon impairments were represented by 5 cases of extensor tenosynovitis and 3 cases of rupture of the extensor pollicis longus due to screws protruding dorsally. Flexor impairments were represented by 2 cases of tenosynovitis and 2 cases of flexor pollicis longus rupture. Screw penetration into the radioulnar joint was observed in 1 case. Loss of reduction was identified in 3 cases. One patient had a deep postoperative infection treated with operative debridement. One patient experienced injury to the median nerve during routine implant removal unrelated to tendon issues. CONCLUSIONS:: The majority of adverse events after volar plate fixation were due to technical errors in implant placement. In our cohort, tendon impairments were the most frequently observed; among these, extensor tendon impairments were the most represented (50% of all adverse events). All 12 tendon-related adverse events were due to technical shortcomings with implant placement. LEVEL OF EVIDENCE:: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence. © 2013 Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited

A Fatal Case of Metastatic Pulmonary Calcification during the Puerperium

We present an unusual case of a fatal respiratory failure in a young woman developed two weeks after she gave birth at home. Circumstantial and clinical features of the case were strongly suggestive for a ‘classical’ septic origin of the respiratory symptoms. Autopsy, together with histopathological and immunohistochemical analyses allowed demonstrating a massive calcium redistribution consisting of an important osteolysis, especially from cranial bones and abnormal accumulation in lungs and other organs. Such physiopathology was driven by a primary hyperparathyroidism secondary to a parathyroid carcinoma as demonstrated by immunohistochemistry. This very rare case is furthermore characterised by a regular pregnancy course, ended with the birth of a healthy new-born. A complex interaction between pregnancy physiology and hyperparathyroidism might be hypothesised, determining the discrepancy between the relative long period of wellness and the tumultuous cascade occurred in the puerperium