Etude expérimentale de la rupture ostéoporotique du col fémoral

L'ostéoporose est une maladie qui affaiblit la structure de l'os par la détérioration de l'architecture trabéculaire et par la diminution de l'épaisseur corticale et l'augmentation de sa porosité. Malgré le coût de santé public, son dépistage n'est pas systématique, et n'est basé que sur l'évaluation de la minéralisation d'un volume osseux à partir de sa projection plane. Aucune information directe sur la structure n'est donnée. Dans le but d'étudier la contribution de la structure osseuse dans la résistance de la partie proximale du fémur, un protocole expérimental simulant la phase d'appui monopodal de la marche, a été développé. Ces essais ont permis de mesurer l'effort à la rupture nécessaire pour provoquer des fractures au niveau du col fémoral semblables aux observations cliniques. Les résultats expérimentaux, serviront à développer un modèle numérique basé sur la théorie des poutres, pour étudier la contribution de l'enveloppe cortical et des faisceaux trabéculaires dans la résistance de la partie proximale du fémur

Altérations de la structure osseuse de l'extrémité proximale du fémur : Analyse en imagerie médicale, étude biomécanique, et application à la prédiction du risque fracturaire.

La fracture ostéoporotique du col fémoral et la coxarthrose constituent aujourd'hui deux enjeux majeurs de santé publique chez les sujets âgés. L'ostéoporose est définie par une diminution de la masse osseuse et une altération de la structure osseuse. La coxarthrose d'autre part associe la perte progressive du cartilage d'encroûtement articulaire, une sclérose osseuse sous-chondrale, des géodes sous-chondrales, et des ostéophytes marginaux. Bien qu'une masse osseuse élevée semble prédisposer à l'arthrose, les relations métaboliques et biomécaniques entre ostéoporose et coxarthrose sont complexes. L'évaluation de l'architecture osseuse de l'extrémité proximale du fémur est un des enjeux majeurs de recherche actuels visant à la caractérisation des modifications du tissu osseux liées au vieillissement. Notre travail de thèse s'est inscrit dans un projet pluridisciplinaire de recherche sur les altérations de la structure osseuse de l'extrémité proximale du fémur, reposant sur une analyse en imagerie médicale et une étude biomécanique de cette région anatomique fondamentale.Fracture of the proximal femur and hip osteoarthritis are nowadays a major public health problem in elderly persons. The current definition of osteoporosis is a low bone mass associated with microarchitecture deterioration. On the other hand, osteoarthritis corresponds to progressive articular cartilage loss, subchondral bone sclerosis, subchondral bone cysts, and marginal osteophytes. Although a higher bone mass may increase the risk of osteoarthritis, osteoporosis and hip osteoarthritis present a complex metabolic and biomechanical relationship. The proximal femur architectural evaluation and characterization of age-related osseous alterations are currently one of the main challenges in bone and mineral research. Our work was based on a multidisciplinary project which aimed at evaluating the age-related structural deterioration of the proximal femur using medical imaging and biomechanical testing in this crucial anatomical region

Osteoid Osteoma of the Midfoot: Percutaneous Radiofrequency Treatment in 2 Cases

International audienceOsteoid osteoma should be considered as a potential diagnosis in cases of chronic midfoot pain in younger individuals. If proper precautions are taken, percutaneous radiofrequency ablation may be considered a safe and efficient alternative to surgical resection in the treatment of osteoid osteomas, even in the small bones of the midfoot. We report on 2 cases of osteoid osteoma, 1 in the lateral cuneiform, and the other at the base of the second metatarsal, that were successfully treated with percutaneous radiofrequency ablation. Preoperative imaging studies, procedure technique, and clinical outcome are presented. (C) 2011 by the American College of Foot and Ankle Surgeons. All rights reserved

Performance diagnostique de l'imagerie dans les lésions de la coiffe des rotateurs (étude comparative de l'échographie, de l'arthroscanner et de l'arthro-IRM)

AIX-MARSEILLE2-BU Méd/Odontol. (130552103) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

Anterolateral knee pain related to thrombosed lateral patellar retinaculum veins: Unusual anterolateral pain of the knee.

Place: United StatesWe describe the ultrasound (US) features of venous thrombosis involving the lateral patellar retinaculum (LPR) veins presenting as anterolateral knee pain. Four male patients, aged 16 to 35 years, were referred for lateropatellar pain with focal tenderness. In two cases, physical examination also demonstrated soft tissue swelling at the anterolateral aspect of the knee. In all four cases, US showed subcutaneous fat edema surrounding a thrombosis involving the LPR veins. Magnetic resonance imaging performed before US in one patient revealed only nonspecific subcutaneous fat edema and was therefore unable to make the correct diagnosis of LPR venous thrombosis

Soft Tissue Masses of the Knee Related to a Focal Defect of the Lateral Patellar Retinaculum.

Place: EnglandWe report on the imaging features of 6 soft tissue masses in the anterolateral aspect of the knee related to a focal defect of the lateral patellar retinaculum. In 4 patients (3 female and 1 male; 6-65 years) presenting with nontender palpable soft tissue masses in the anterolateral aspect of their knees, ultrasonography showed a focal defect of the lateral patellar retinaculum with herniation of the Hoffa fat pad, which was only visible in flexion. A magnetic resonance imaging examination performed in 1 case confirmed the defect in the lateral patellar retinaculum but did not show a mass, as the knee was examined only at 10° of flexion. The 2 remaining patients (one male and 1 female; 62 and 55 years) presented with soft tissue masses in their anterolateral knees in both flexion and extension. These masses were related respectively to a lipoma of the Hoffa fat pad and to a ganglion cyst, both herniated through a defect of the lateral patellar retinaculum. Our cases suggest that a focal defect of the lateral patellar retinaculum may be a route for Hoffa fat pad herniation as well as a route for superficial extension of infrapatellar fat lesions such as lipomas and ganglion cysts

Anterolateral knee pain related to thrombosed lateral patellar retinaculum veins: Unusual anterolateral pain of the knee

Place: United StatesWe describe the ultrasound (US) features of venous thrombosis involving the lateral patellar retinaculum (LPR) veins presenting as anterolateral knee pain. Four male patients, aged 16 to 35 years, were referred for lateropatellar pain with focal tenderness. In two cases, physical examination also demonstrated soft tissue swelling at the anterolateral aspect of the knee. In all four cases, US showed subcutaneous fat edema surrounding a thrombosis involving the LPR veins. Magnetic resonance imaging performed before US in one patient revealed only nonspecific subcutaneous fat edema and was therefore unable to make the correct diagnosis of LPR venous thrombosis

ANATOMICAL STUDY OF THE INFRAPATELLAR BRANCH OF THE SAPHENOUS NERVE USING ULTRASONOGRAPHY

International audienceIntroduction: The purpose of this study was to determine whether ultrasonography allows precise assessment of the course and relations of the infrapatellar branch of the saphenous nerve. Methods: This work, initially undertaken in 5 cadavers, was followed by high-resolution ultrasonographic study in 10 healthy volunteers. The location and relations of the infrapatellar branch of the saphenous nerve to the adjacent anatomical structures were analyzed. The course of the nerve was classified according to its relation to the sartorius muscle as posterior or penetrating. Results: The infrapatellar branch of the saphenous nerve could be identified consistently along the majority of its course by ultrasonography. Useful landmarks for the detection of the nerve could be defined. Some anatomical variations were noted. Conclusions: The infrapatellar branch of the saphenous nerve can be depicted by ultrasonography. Precise mapping of its anatomical course may have significant clinical applications. Muscle Nerve 44: 50-54, 201

Articular angioleiomyoma presenting as cyclic hip pain

International audienceno abstrac

Correction to: Stenosing tenosynovitis of the extensor digitorum tendons of the hand: clinical and sonographic features.

Place: German