E. Pluot

Is Superolateral Hoffa Fat Pad Edema a Consequence of Impingement between Lateral Femoral Condyle and Patellar Ligament

PURPOSE To evaluate whether knee extensor mechanism features are associated with superolateral Hoffa fat pad edema at magnetic resonance imaging. MATERIALS AND METHODS Institutional review board approval and written consent from all patients were obtained. Patients with superolateral Hoffa fat pad edema (n = 30) and a control group without edema of the fat pad (n = 60) were evaluated prospectively with magnetic resonance (MR) imaging. Demographic data and extensor mechanism features were compared, including trochlear depth, lateral trochlear inclination, patellar tilt angle, patellar height ratio, distance between patellar ligament and lateral trochlear facet, distance from the tibial tubercle to the trochlear groove, patellar facet asymmetry, and patellar ligament abnormalities. RESULTS The following variables were associated with superolateral Hoffa fat pad edema in the multivariable models: patellar height ratio (P = .023), shortest distance between patellar ligament and lateral trochlear facet (P < .001), and distance from the tibial tubercle to the trochlear groove (P = .046). Of all demographic and degenerative variables, only age was significantly associated, with younger patients more likely to have superolateral Hoffa fat pad edema (P < .009). CONCLUSION A high-riding patella, a short distance between the patellar ligament and the lateral trochlear facet, and an increased distance from the tibial tubercle to the trochlear groove are associated with superolateral Hoffa fat pad edema at MR imaging. These results are suggestive of impingement between the lateral femoral condyle and the posterior aspect of the patellar ligament in these patients.

Role of Imaging in Spine, Hand, and Wrist Osteoarthritis

Osteoarthritis (OA) of the wrist is mainly secondary to traumatic ligamentous or bone injuries. Involvement of the radiocarpal joint occurs early on in the disease, whereas the mediocarpal joint is involved at a later stage. Metabolic diseases may also involve the wrist and affect specific joints such as the scapho-trapezio-trapezoid joint. Although OA of the wrist is routinely diagnosed on plain films, a thorough assessment of cartilage injuries on computed tomographic arthrography, magnetic resonance imaging (MRI), or MR arthrography remains necessary before any surgical procedure. OA of the fingers is frequently encountered in postmenopausal women. Distal interphalangeal joints and trapezio-metacarpal joint are the most frequently involved joints. Whereas the clinical diagnosis of OA of the wrist and hand is straightforward, the therapeutic management of symptomatic forms remains unclear, with no clear guidelines. OA of the spine is related to degenerative changes of the spine involving the disc space, vertebral endplates, the facet joints, or the supportive and surrounding soft tissues. The sequelae of disc degeneration are among the leading causes of functional incapacity in both sexes, and are a common source of chronic disability in the working years. Disc degeneration involves structural disruption and cell-mediated changes in composition. Radiography remains usually the first-line imaging method. MRI is ideally suited for delineating the presence, extent, and complications of degenerative spinal disease. Other imaging modalities such as computed tomography, dynamic radiography, myelography, and discography may provide complementary information in selected cases, especially before an imaging-guided percutaneous treatment or spinal surgery. The presence of degenerative changes on imaging examinations is by no means an indicator of symptoms, and there is a high prevalence of lesions in asymptomatic individuals. This article focuses on imaging of OA of the wrist and hand, as well as lumbar spine OA, with an emphasis on current MRI grading systems available for the assessment of discovertebral lesions.

Osteoarthritis of the Wrist and Hand, and Spine

Although osteoarthritis (OA) of the wrist and fingers is routinely diagnosed using plain film, a thorough assessment of cartilage injuries using CT-arthrography, MR imaging, or MR-arthrography remains necessary before any surgical procedure. MR imaging is ideally suited for delineating the presence, extent, and complications of degenerative spinal disease, including OA of the spine involving the disk space, vertebral endplates, facet joints, or supportive and surrounding soft tissues. Other imaging modalities such as CT, dynamic radiography, myelography, and discography may provide complimentary information in selected cases. This article focuses on imaging of OA of the wrist and hand and the lumbar spine, with an emphasis on current MR imaging grading systems available for the assessment of discovertebral lesions.

Comment je fais un bilan échographique des mains et des pieds dans la polyarthrite rhumatoïde

Rheumatoid arthritis (RA) is a chronic inflammatory disease characterized by progressive damage of synovial-lined joints and variable extra-articular manifestations. Synovitis is usually found in the wrist, metacarpophalangeal, proximal interphalangeal and metatarsophalangeal joints. For these reasons, we believe that ultrasound with power doppler can be used for the detection and monitoring of synovitis with a simplified “hands and feet” protocol. In this article, we will describe this protocol used daily in our institution for early diagnosis and therapeutic management of this disease.

Scapula alata dynamique d’origine neuromusculaire : diagnostic clinique, électromyographique et à l’imagerie par résonance magnétique

Dyskinesia of the scapula is a clinical diagnosis and includes all disorders affecting scapula positioning and movement whatever its etiology. Scapular winging is a subtype of scapular dyskinesia due to a dynamic prominence of the medial border of the scapula (DSW) secondary to neuromuscular imbalance in the scapulothoracic stabilizer muscles. The two most common causes of DSW are microtraumatic or idiopathic lesions of the long thoracic nerve (that innerves the serratus anterior) or the accessory nerve (that innerves the trapezius). Diagnosis of DSW is clinical and electromyographic. Use of magnetic resonance imaging (MRI) could be of interest to distinguish lesion secondary to a long thoracic nerve from accessory nerve and to rule out scapular dyskinesia related to other shoulder disorders. Causal neuromuscular lesion diagnosis in DSW is challenging. Clinical examinations, combined with scapular MRI, could help to their specific diagnosis, determining their stage, ruling out differential diagnosis and thus give raise to more targeted treatment.

IRM du rachis et des articulations sacro-iliaques dans la spondylarthrite ankylosante

MR Imaging of the spine and sacroiliac joints in ankylosing spondylitis The new diagnostic criteria for spondyloarthropathy include MRI. MRI frequently allows early diagnosis of inflammatory lesions of the spine and sacroiliac joints in patients with normal plain films. Moreover, MRI is useful for the detection and quantification of inflammatory and structural lesions, and to assess disease activity.

Chondrosarcomes dédifférenciés : revue iconographique radio-pathologique

Dedifferentiated chondrosarcoma : radiologic-pathologic correlation Dedifferentiated chondrosarcomas are highly malignant tumors characterized by conventional low-grade chondrosarcoma with abrupt transition to foci that have dedifferentiated into a higher-grade noncartilaginous more aggressive sarcoma. The dedifferentiated component, an osteosarcoma or fibrosarcoma, determines the prognosis. Its identification is key for management. A diagnosis of dedifferentiated chondrosarcoma should be suggested by the presence of “tumoral dimorphism” with cartilaginous component and aggressive lytic component invading adjacent soft tissues.

IRM et spondylarthropathie

Objectifs Connaitre le protocole IRM pour explorer une SPA. Connaitre la semiologie IRM d’une SPA. Savoir distinguer une IRM avec signes d’activite d’une IRM avec signes de maladie chronique. Messages a retenir L’apport de l’IRM est certain pour le diagnostic precoce, meme si cet examen peut etre negatif dans une vraie spondylarthrite. Les cohortes actuellement en cours de constitution, telle la cohorte nationale DESIR (DEvenir des Spondylarthropathies Indifferenciees Recentes), devraient, a terme, offrir un outil de travail susceptible d’evaluer de nouveaux algorithmes de diagnostic precoce, et de mieux preciser la place de l’imagerie en pratique courante. Resume Une IRM des sacro-iliaques doit etre realisee en sequence STIR (suppression de graisse) et en sequence Tl. L’injection intraveineuse de gadolinium n’est pas utile en pratique courante dans cette indication. L’IRM du rachis entier apporte des informations supplementaires et peut donc etre conseillee : il n’existe cependant pas de consensus a ce sujet, pour notre part nous conseillons cet examen. Il est important de preciser qu’il s’agit d’une recherche d’inflammation, afin que les sequences adaptees (STIR) soient realisees.

Hémangiome épithélioïde intraosseux : à propos d’une localisation fémorale

Une patiente de 37 ans consulte pour des douleurs non systématisées du membre inférieur évoluant depuis plusieurs mois sans notion de traumatisme. L’examen clinique ne note pas de masse palpable mais la douleur est déclenchée en palpant la diaphyse fémorale droite. Les radiographies mettent en évidence une lésion lytique plurilobulée à bord net (fig. 1) . Le scanner confirme le caractère lytique de la lésion avec une petite zone de rupture corticale antérieure et une large zone de rupture corticale à la partie postérieure (fig. 2) . L’IRM (fig. 3) confirme ces données et montre une lésion unique en hypersignal T2 très intense avec un début d’envahissement des parties molles. Il existe une faible réaction inflammatoire péri lésionnelle. Il n’y a pas de niveau liquide-liquide. Une microbiopsie percutanée est réalisée sous contrôle tomodensitométrique. Celleci met en évidence des images compatibles avec un hémangiome épithélioïde mais nécessitant de plus larges prélèvements. L’analyse histologique de la biopsie chirurgicale complémentaire confirme cette hypothèse en montrant de très nombreux vaisseaux de forme et de taille variée, souvent larges à contours anfractueux (fig. 4a) , bordés par des cellules endothéliales d’aspect épithélioïde, faisant saillie dans la lumière vasculaire (fig. 4b) .

OA-WP-6 Arthrose de la main et du poignet : qu’attendre du bilan d’imagerie ?

Objectifs pedagogiques Reconnaitre les signes precoces en imagerie de l’arthrose de la main et du poignet. Connaitre les multiples formes etiologiques et topographiques de l’arthrose de la main et du poignet. Connaitre l’apport des differentes techniques d’imagerie dans le bilan pre-therapeutique. Messages a retenir Les radiographies rigoureusement realisees -incidences specifiques, mesure de la pente trapezienne-dominent le bilan diagnostique et pronostique des arthroses peri-trapeziennes. L’echographie et l’IRM permettent le diagnostic de certaines complications peri-articulaires : atteinte scapho-trapezienne et tendinopathie du FCR, arthrose piso-triquetrale et syndrome canalaire du Guyon, arthrose inter-phalangienne distale et kystes mucoides. L’arthrose radio-carpienne est presque toujours post-traumatique : SLAC et SNAC wrists. L’arthrose ulno-carpienne doit faire rechercher des elements anato-miques en faveur d’un syndrome d’impaction ulno-carpien : valeur de la variance ulnaire.