Arthroscopic Management of Intra-articular Ligament Lesions on Distal Radius Fractures

AbstractArticular distal radius fractures (DRFs) have increased in incidence in recent years, especially among the economically active population. Most of the treatment approaches are based on plain X- rays, and do not give us any information on how to treat these fractures. In the search for solutions with greater precision in diagnosis, in reducing the joint surface of the fracture, and envolving minimally-invasive techniques, we found arthroscopy as the main tool for these patients. Therefore, an enhanced understanding of the biomechanics of the different types of fracture associated with ligamentous lesions should facilitate the right decision regarding the treatment. The present paper aims at providing a management-oriented concept to diagnose and treat ligamentous lesions associated with intra-articular DRFs based on a arthroscopy-assisted procedure, and showing the objective and patient-reported outcomes and a new classification. The objective and patient-reported outcomes were: the mean range of motion (ROM) was of 94.80% on the non-affected side; the mean score on the abbreviated version of the Disabilities of the Arm, Shoulder and Hand questionnaire (QuickDASH) was of 3.6 (range: 1 to 12). The score on the Visual Analog Scale (VAS) was of 1.66 (range: 1 to 3). Complications were observed in 2 (13.33%) patients: extensor tendon synovitis in 1 patient, and a limitation (stiffness) in ROM in 1 patient, both treated with wrist arthroscopy release. The mean time until the return to work was of 6.4 weeks. In patients with unstable intra-articular DRFs associated with ligamentous lesions, the fixation of specific osseous-ligamentous fragments and ligamentous repair/reconstruction by wrist arthroscopy prove to be a safe and reliable treatment. The clinical and functional results predict that the patients can return to work more quickly

Distal Articular Fractures of the Humerus: Surgical Approach with Dynamic Elbow external Fixator

Abstract Purpose To measure clinical and radiographic outcomes using external fixation in distal humeral fractures. Methods A total of 10 elderly patients, with a mean age of 71 (range 64–84 years) years old, with unstable distal humeral fractures were treated by percutaneous reduction and fixation with an articulated external fixator. The patients were assessed on range of elbow motion, patient disabilities of the arm, shoulder, and hand (DASH), and pain visual analog scale (VAS) and radiographic evaluation at 12 months. Results The mean range of motion was 134° of flexion, extension was of - 5°. All of the elbows were clinically stable. The mean VAS was 2.2, and the mean DASH score was 14.3. Radiographic analysis showed satisfactory reduction and consolidation. All of the patients showed congruence of concentric humerus-ulnar and radius and no patient had joint stiffness or posttraumatic arthritis of the elbow. Regarding complications, we observed a patient who presented with pain in the location of the ulnar pin, which was resolved with the removal of the pin. After two months, another patient had pneumonia and died. The follow-up was of 15.44 months. Conclusions A radiographic analysis of the patients showed fracture healing with joint congruity. In the functional clinical aspect, it was noted that patients had functional range of motionType of study/level of evidence Therapeutic I

TelemicrosurgeryRobot Assisted Microsurgery /

XII, 203 p. 126 illus., 105 illus. in color.onlin

Dorsal capsulodesis associated with arthoscopy-assisted scapholunate ligament reconstruction using a palmaris longus tendon graft

ABSTRACT OBJECTIVES: To measure the quality of life, the time to work return, and clinical, functional, and radiographic parameters of patients treated with dorsal capsulodesis associated with scapholunate (SL) reconstruction, assisted by arthroscopy. METHODS: From January 2015 to September 2016, 14 adult patients with SL dissociation underwent surgical treatment with the SL reconstruction procedure assisted by arthroscopy, using the new technique proposed in this study. All patients were assessed by the occupational therapy department at regular intervals after surgery and performed the same sequence of rehabilitation. The parameters analyzed were: range of motion (ROM), Disability of the Arm, Shoulder, and Hand (DASH), visual analog scale (VAS), and radiographic analysis to visualize the pre- and postoperative SL gap and the pre- and postoperative dorsal intercalated segment instability (DISI) deformity the. The complications and the time to return to work activities were described. RESULTS: The follow-up time was 12 months (3-17). The ROM averaged 321° (96.9% of the normal side). VAS was 1.79/10 (1-6). DASH was 6.50/100 (1-30). The time to work return work was 4.42 months (2-17). As for complications, one patient developed SLAC, and underwent four-corner fusion one year after ligament reconstruction. Currently, he has experienced pain relief, with a functional range of motion of the wrist, and has not yet returned to professional activities. The preoperative SL gap was 4.29 mm (2-7); in the postoperative period, it was 1.79 mm (1-4). The DISI deformity was present in ten patients with SL angle > 70° (preoperative) and it was corrected after surgery, in all patients. SLAC stage I was identified in a patient. Arthroscopy was performed in all cases. The SL instability was classified as Geissler grade III in four cases and as grade IV in ten cases. CONCLUSION: The new approach (dorsal capsulodesis associated with SL reconstruction, assisted by arthroscopy) presented in this study is safe and effective in the treatment of SL dissociation, since it offers satisfactory clinical, radiographic and functional results, showing low rates of complications. For patients, it allows the return to their social and professional activities, and increases their life quality

Measurement of pseudorapidity distributions of charged particles in proton-proton collisions at sqrt(s) = 8 TeV by the CMS and TOTEM experiments

Pseudorapidity ( $\eta$ ) distributions of charged particles produced in proton–proton collisions at a centre-of-mass energy of 8 $~\text {TeV}$ are measured in the ranges $|\eta | < 2.2$ and $5.3 < |\eta | < 6.4$ covered by the CMS and TOTEM detectors, respectively. The data correspond to an integrated luminosity of $\mathcal {L} = 45 \mu {\mathrm {b}}^{-1}$ . Measurements are presented for three event categories. The most inclusive category is sensitive to 91–96 % of the total inelastic proton–proton cross section. The other two categories are disjoint subsets of the inclusive sample that are either enhanced or depleted in single diffractive dissociation events. The data are compared to models used to describe high-energy hadronic interactions. None of the models considered provide a consistent description of the measured distributions

Search for high-mass exclusive diphoton production with tagged protons in proton-proton collisions at s= \sqrt{s} = 13 TeV

A search is presented for high-mass exclusive diphoton production via photon-photon fusion in proton-proton collisions at $\sqrt{s} =$ 13 TeV in events where both protons survive the interaction. The analysis utilizes data corresponding to an integrated luminosity of 103 fb$^{-1}$ collected in 2016--2018 with the central CMS detector and the CMS and TOTEM precision proton spectrometer (PPS). Events that have two photons with high transverse momenta ($p_{\mathrm{T}}^{\gamma} >$ 100 GeV), back-to-back in azimuth, and with a large diphoton invariant mass ($m_{\gamma\gamma} >$ 350 GeV) are selected. To remove the dominant inclusive diphoton backgrounds, the kinematic properties of the protons detected in PPS are required to match those of the central diphoton system. Only events having opposite-side forward protons detected with a fractional momentum loss between 0.035 and 0.15 (0.18) for the detectors on the negative (positive) side of CMS are considered. One exclusive diphoton candidate is observed for an expected background of 1.1 events. Limits at 95% confidence level are derived for the four-photon anomalous coupling parameters $|\zeta_1|$ 100 GeV), back-to-back in azimuth, and with a large diphoton invariant mass ($m_{\gamma\gamma} \gt$ 350 GeV) are selected. To remove the dominant inclusive diphoton backgrounds, the kinematic properties of the protons detected in PPS are required to match those of the central diphoton system. Only events having opposite-side forward protons detected with a fractional momentum loss between 0.035 and 0.15 (0.18) for the detectors on the negative (positive) side of CMS are considered. One exclusive diphoton candidate is observed for an expected background of 1.1 events. Limits at 95% confidence level are derived for the four-photon anomalous coupling parameters $\lvert\zeta_1\rvert \lt$ 0.073 TeV$^{-4}$ and $\lvert\zeta_2\rvert \lt$ 0.15 TeV$^{-4}$, using an effective field theory. Additionally, upper limits are placed on the production of axion-like particles with coupling strength to photons $f^{-1}$ that varies from 0.03 TeV$^{-1}$ to 1 TeV$^{-1}$ over the mass range from 500 to 2000 GeV

Nonresonant central exclusive production of charged-hadron pairs in proton-proton collisions at s\sqrt{s} = 13 TeV

International audienceThe central exclusive production of charged-hadron pairs in pp collisions at a centre-of-mass energy of 13\TeV is examined, based on data collected in a special high-$\beta^*$ run of the LHC. The nonresonant continuum processes are studied with the invariant mass of the centrally produced two-pion system in the resonance-free region, $m_{\pi^+\pi^-}$$\lt$ 0.7 GeV or $m_{\pi^+\pi^-}$$\gt$ 1.8 GeV. Differential cross sections as functions of the azimuthal angle between the surviving protons, squared exchanged four-momenta, and $m_{\pi^+\pi^-}$ are measured in a wide region of scattered proton transverse momenta, between 0.2 and 0.8 GeV, and for pion rapidities $\lvert y\rvert$$\lt$ 2. A rich structure of interactions related to double-pomeron exchange is observed. A parabolic minimum in the distribution of the two-proton azimuthal angle is observed for the first time. It can be interpreted as an effect of additional pomeron exchanges between the protons from the interference between the bare and the rescattered amplitudes. After model tuning, various physical quantities are determined that are related to the pomeron cross section, proton-pomeron and meson-pomeron form factors, pomeron trajectory and intercept, and coefficients of diffractive eigenstates of the proton

Proton reconstruction with the CMS-TOTEM Precision Proton Spectrometer

International audienceThe Precision Proton Spectrometer (PPS) of the CMS and TOTEM experiments collected 107.7 fb$^{-1}$ in proton-proton (pp) collisions at the LHC at 13 TeV (Run 2). This paper describes the key features of the PPS alignment and optics calibrations, the proton reconstruction procedure, as well as the detector efficiency and the performance of the PPS simulation. The reconstruction and simulation are validated using a sample of (semi)exclusive dilepton events. The performance of PPS has proven the feasibility of continuously operating a near-beam proton spectrometer at a high luminosity hadron collider