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We report results with the INCA® distal scaphoid pole resurfacing implant anchored within the scaphoid for isolated scaphotrapeziotrapezoid osteoarthritis. Thirty-five implants in 27 patients (mean age, 69 years) were retrospectively included with a minimum follow-up of 2 years. Outcome criteria were pain (VAS), PROMs (QuickDASH, PRWE and MMWS), wrist motion, pinch and grip strength, and radiographic assessment. The average follow-up was 4.6 years. There was a significant improvement in pain, PROMs, grip and pinch strength. Radial deviation and wrist extension showed slight but significant postoperative decrease (-4° for both). Dorsal intercalated segment instability (DISI) was significantly improved postoperatively (7 cases versus 21 preoperatively). There were 2 cases of implant loosening (6%) within the first 10 months: 1 keel malpositioning and 1 insufficient postoperative immobilization. These findings suggest that the INCA® implant is an effective and reliable medium-term solution for isolated scaphotrapeziotrapezoid osteoarthritis. By restoring scaphoid length and gliding on the trapeziotrapezoid surface, the implant contributes to restoring normal bone alignment of the wrist.

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In 1970, Jean-Yves de la Caffinière developed the first trapeziometacarpal (TMC) joint prosthesis, a ball-and-socket design based on hip replacement implants. From 1970 to 1990, the first generation of cemented prostheses was developed. At that time, trapeziectomy, with tendon interposition or suspension arthroplasty, and Swanson silastic spacers remained the most widely used surgical procedures for thumb basal joint arthritis. From 1990 to 2010, a second generation of cementless prostheses was developed. The third generation was introduced after 2010 and consisted of dual mobility prostheses. In 2020, TMC arthroplasty (simple or dual mobility) is a reliable option in thumb basal joint arthritis with an implant survival rate of 90% at 10 years of follow-up, while providing pain relief and restoring strength and mobility. Restoration of the thumb's length corrects most thumb Z-deformities, so the TMC joint prosthesis may be a viable alternative surgical solution to trapeziectomy, which remains the gold standard in English-speaking countries. Moreover, trapeziectomy after failed TMC arthroplasty provides outcomes equivalent to those of primary trapeziectomy.

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PURPOSE: To assess the impact of iterative reconstructions on image quality and detectability of focal liver lesions in low-energy monochromatic images from a Fast kV-Switching Dual Energy CT (KVSCT) platform. METHODS: Acquisitions on an image-quality phantom were performed using a KVSCT for three dose levels (CTDIvol:12.72/10.76/8.79 mGy). Raw data were reconstructed for five energy levels (40/50/60/70/80 keV) using Filtered Back Projection (FBP) and four levels of ASIR (ASIR30/ASIR50/ASIR70/ASIR100). Noise power spectrum (NPS) and task-based transfer function (TTF) were measured before computing a Detectability index (d') to model the detection task of liver metastasis (LM) and hepatocellular carcinoma (HCC) as function of keV. RESULTS: From 40 to 70 keV, noise-magnitude was reduced on average by -68% ± 1% with FBP; -61% ± 3% with ASIR50 and -52% ± 6% with ASIR100. The mean spatial frequency of the NPS decreased when the energy level decreased and the iterative level increased. TTF values at 50% decreased as the energy level increased and as the percentage of ASIR increased. The detectability of both lesions increased with increasing dose level and percentage of ASIR. For the LM, d' peaked at 70 keV for all reconstruction types, except for ASIR70 at 12.72 mGy and ASIR100, where d' peaked at 50 keV. For HCC, d' peaked at 60 keV for FBP and ASIR30 but peaked at 50 keV for ASIR50, ASIR70 and ASIR100. CONCLUSIONS: Using percentage of ASIR above 50% at low-energy monochromatic images could limit the increase of noise-magnitude, benefit from spatial resolution improvement and hence enhance detectability of subtle low contrast focal liver lesions such as HCC.

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INTRODUCTION: Coracoid bone graft transfer has become the gold standard in patients with recurrent anterior shoulder instability associated with bony defect. Several studies have shown that the main stabilizing component of this procedure is the sling effect by the conjoint tendon and the lower portion of subscapularis (SS). The purpose of this study was to determine whether a larger SS volume below the bone block was correlated to greater postoperative shoulder stability. MATERIALS AND METHODS: This prospective study included a cohort of patients who underwent open coracoid bone graft transfer for post-traumatic recurrent anterior shoulder instability. Forty patients were reviewed at 2 years with a clinical and CT scan evaluation. A correlation analysis assessed the relation between the SS volume index (ratio of SS volume below the bone block to volume over the bone block) and Rowe and Walch-Duplay instability scores. RESULTS: There exists a positive and significant correlation between SS volume index and postoperative Rowe score, r=0.37 (P=0.03). The same trend was observed for Walch-Duplay score without statistical significance. A larger inferior SS volume did not result in a limitation of external rotation, greater fatty infiltration, or malposition of the coracoid graft. CONCLUSION: A larger SS volume below the bone block is related to greater postoperative shoulder stability. We recommend performing the split in the middle of the SS or higher instead of the junction of the superior two-thirds and inferior one-third as usually reported. LEVEL OF EVIDENCE: III, prospective study.

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We report on single electronic spins coupled to the motion of mechanical resonators by a novel mechanism based on crystal strain. Our device consists of single-crystal diamond cantilevers with embedded nitrogen-vacancy center spins. Using optically detected electron spin resonance, we determine the unknown spin-strain coupling constants and demonstrate that our system resides well within the resolved sideband regime. We realize coupling strengths exceeding 10 MHz under mechanical driving and show that our system has the potential to reach strong coupling. Our novel hybrid system forms a resource for future experiments on spin-based cantilever cooling and coherent spin-oscillator coupling.

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We have demonstrated an integrated three terminal device for the modulation of the complex refractive index of a distributed feedback quantum cascade laser (QCL). The device comprises an active region to produce optical gain vertically stacked with a control region made of asymmetric coupled quantum wells (ACQW). The optical mode, centered on the gain region, has a small overlap also with the control region. Owing to the three terminals an electrical bias can be applied independently on both regions: on the laser for producing optical gain and on the ACQW for tuning the energy of the intersubband transition. This allows the control of the optical losses at the laser frequency as the absorption peak associated to the intersubband transition can be electrically brought in and out the laser transition. By using this function a laser modulation depth of about 400 mW can be achieved by injecting less than 1 mW in the control region. This is four orders of magnitude less than the electrical power needed using direct current modulation and set the basis for the realisation of electrical to optical transducers.

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We present an experimental and theoretical study of the optical properties of metal-dielectric-metal structures with patterned top metallic surfaces, in the THz frequency range. When the thickness of the dielectric slab is very small with respect to the wavelength, these structures are able to support strongly localized electromagnetic modes, concentrated in the subwavelength metal-metal regions. We provide a detailed analysis of the physical mechanisms which give rise to these photonic modes. Furthermore, our model quantitatively predicts the resonance positions and their coupling to free space photons. We demonstrate that these structures provide an efficient and controllable way to convert the energy of far field propagating waves into near field energy.

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It is rare for portal vein thrombosis to complicate colorectal liver metastases. However malignant portal vein thrombosis must be anticipated when considering hepatic resection. While this finding may influence long-term survival, it does not absolutely contraindicate hepatic resection. We report here a case of colorectal metastasis to the liver with associated macroscopic malignant portal vein thrombosis treated with hepatic resection; the patient is free from recurrence at 5-year follow-up.

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Symptoms of chronic myelopathy in cases of paraspinal arteriovenous malformations are most often related to perimedullary venous drainage. Here, we report on three cases of such malformations that have unique epidural venous drainage. These thoracolumbar lesions manifested as isolated back pain (in two cases) and S1 lumboradicular pain (in one case). MRI presented evidence to suggest a diagnosis of these rare conditions, based on signs of vertebral erosion, signal loss (flow void) on T1- and T2-weighted imaging, and partial enhancement after gadolinium injection, with no signs of congestive myelopathy. Spinal angiography confirmed the presence of a paraspinal fistula and, at the same time, allowed treatment by intra-arterial onyx injection.

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OBJECTIVE: Development of upper limb functional surgery in tetraplegics in the last 50 years. METHODS: The literature review relating to the years 1950-2002 was carried out with 3 data bases: Medline, Pascal, Embase. This review also involved a thorough study of non-indexed references. RESULTS: A large number of surgical procedures are described. Two priorities are stressed by the authors: safety of these procedures and duration of postoperative immobilization. CONCLUSION: This review of literature shows that the prospects for restoring upper limb function in tetraplegics are greater than ever, offering a larger number of patients the possibility to increase their independence in daily life. Functional surgery remains, nevertheless, demanding in terms of length of immobilization and presupposes requiring a multidisciplinary approach requiring rehabilitation teams to be up to date with surgical procedures.

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Progressive ankylosis of the trapeziometacarpal joint in flexion-adduction with closure of the first web in advanced trapeziometacarpal osteoarthritis gradually leads to compensatory dislocation of the metacarpophalangeal joint with hyperextension in the sagittal plane and abduction in the frontal plane. This deformity of the MP joint, initially reducible, but subsequently irreducible, results in the classical 'Z' deformity of the thumb in the sagittal plane. A less well known 'Z' deformity can also occur in the frontal plane due to distension of the medial collateral ligament. Surgical treatment of trapeziometacarpal osteoarthritis by arthroplasty must correct this secondary deformity of the MP joint to obtain an optimal result. The classical sagittal 'Z' deformity of the thumb can be easily corrected while this deformity is still reductible by releasing the fist metacarpal by tightening the abductor pollicis longus. When it is irreducible, this deformity can only be treated by MP arthrodesis, which contraindicates insertion of the ARPE trapeziometacarpal implant. Correction of the frontal 'Z' deformity of the thumb requires repair of the medial collateral ligament of the MP joint by ligamentorraphy (retightening) or ligamentoplasty.

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US and MRI currently are the best imaging modalities to evaluate pathology of the uterine cervix and vagina. Carcinoma of the cervix is the most frequent indication for imaging. MRI allows preoperative staging of cervical carcinoma based on FIGO classification, and post treatment follow-up. Other uterine cervix diseases are less frequently imaged and include a wide range of entities that most frequently cause increased T2W signal at MR imaging. Pathology of the pelvic floor, vagina, vulva, and perineum also includes a wide range of entities that have seldom been described in the imaging literature.

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A 21-year-old male of Moroccan descent was admitted for inflammatory polyarthralgia and monoarthritis of the left knee. The patient reported a history of recurrent isolated aphthous ulcerations of the oral cavity. He was found to be positive for the HLA B5 antigen. The other investigations for Behçet's disease were negative. During hospitalization, headache responsible for insomnia developed. Neurologic evaluation was normal, as well as funduscopy and spinal tap findings. CT scan images were suggestive of cerebral thrombophlebitis. Magnetic resonance imaging (MRI) disclosed an old thrombosis of the right transverse sinus. Time-of-flight MRI (MRI with sequences adapted to the study of vessels) evidenced recent thrombophlebitis of the left transverse sinus. Cerebral angiography fully confirmed MRI findings. Treatment with a corticosteroid and an anticoagulant was successful. Final diagnosis was Behçet's disease. Subsequently, the patient developed additional features of the disease, including hypersensitivity to pinprick, retinal vasculitis, and erythema nodosum. This case is interesting for two reasons: cerebral thrombophlebitis in Behçet's disease can manifest as localized headache. It occurs in 6 to 13% of patients. Early diagnosis and treatment are essential; MRI features of cerebral thrombophlebitis were confirmed by the cerebral angiogram. MRI established that the thrombophlebitis was of recent onset. MRI may be appropriate as the initial investigation in patients with suspected cerebral thrombophlebitis.

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Surgical rehabilitation of the upper limb in quadriplegia aims to restore prehension function. Surgical restoration always involves active extension of both elbow and wrist. Anesthesia, which first aim is to allow adequate surgical conditions, must adapt to the patient's disability. In this particular setting, regional anesthesia and especially brachial plexus block techniques represents our priority choice.

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