Xavier Demondion

Acetabular labrum: MRI in asymptomatic volunteers.

PURPOSE The purpose of this study was to describe the MR appearance of the acetabular labrum in asymptomatic hips on high resolution MRI. METHOD Fifty-two hips in 46 asymptomatic volunteers with an age range of 15-85 years were evaluated with coronal and axial T1-weighted and T2-weighted sequences. The shape, margin, size, and signal intensity of the acetabular labrum were analyzed. RESULTS The labrum was absent in its anterosuperior aspect in five hips (10%). Intralabral regions of intermediate of high signal intensity were detected in 30 hips (58%) imaged with T1-weighted and proton density-weighted sequences. Intralabral linear hyperintense foci reaching the articular surface and consistent with a labral tear were detected in four labra on T2-weighted images. Intralabral microcysts were seen in three labra. CONCLUSION The MR appearance of the hip labrum is varied in asymptomatic volunteers. Intralabral increased signal intensity and absent anterosuperior labra are especially frequent and may represent asymptomatic lesions or normal variations.

Early Rheumatoid Arthritis: A Review of MRI and Sonographic Findings

OBJECTIVE The introduction of anti-tumor necrosis factor alpha agents has opened new prospects in therapeutic management of patients with early rheumatoid arthritis, thereby creating new demands on radiologists to identify patients with aggressive disease at an early stage. As a result, imaging techniques such as MRI and sonography have developed during the past few years. CONCLUSION This article illustrates the imaging findings that may be encountered with these techniques in patients with early rheumatoid arthritis.

Inter- and intraobserver reproducibility in radiographic diagnosis and classification of femoral trochlear dysplasia

Dejour’s radiographic criteria are commonly used to diagnose and assess femoral trochlear dysplasia in case of patello-femoral instability. The aim of this study was to establish the intra- and interobserver reliability of these radiographic criteria. Sixty-eight lateral knee radiographs were examined independently by 7 observers (2 juniors, 5 seniors) to assess interobserver agreement, and the 2 juniors repeated the observations to test intraobserver agreement. These 68 true lateral views were harvested from clinical records of 64 patients who underwent a trochleoplasty because of patellofemoral instability. To evaluate the agreement on analytic data (morphologic type of trochlea) we used the kappa statistical method, and to evaluate the agreement on numerical data (depth and prominence of the trochlear groove) we used interclass correlation analysis. The “crossing sign” (between the trochear groove and the anterior aspect of both condyles) was reliable since the probability of rating as normal a pathologic trochlea was only 3.1% (0 to 8.8%). In classifying trochlear morphology interobserver agreement was slight (kappa = 0.17) and intraobserver agreement was fair (kappa = 0.3). On the other hand, the measurements of the depth and prominence of the trochlear groove were more reliable since the interclass coefficients between observers were 0.62 and 0.38 respectively. The most frequent interobserver error was related to misdiagnosis of type II. To clarify Dejour’s criteria we propose a diagnosis of type II only when 5 mm or more are measured betweeen the intersections with the medial and lateral femoral condyles. We recommand the use of the prominence of the trochlear groove to evaluate the grade of bony trochlear dysplasia.

Ultrasonographic evaluation of normal extrinsic and intrinsic carpal ligaments: preliminary experience

ObjectiveTo determine normal anatomy of extrinsic and intrinsic carpal ligaments at ultrasonography (US).Design and volunteersIn the first part of the study, two musculoskeletal radiologists retrospectively reviewed in consensus the photographs of anatomic sections and dissections derived from 20 cadaveric wrists. This cadaveric study gave the two readers the opportunity to learn the anatomy and orientation of the various extrinsic and intrinsic carpal ligaments and, thus, to develop a US protocol to facilitate the recognition of each carpal ligament. In the second part of the study, these two radiologists prospectively and independently evaluated the visibility of extrinsic and intrinsic carpal ligaments in 30 wrists of volunteers, using the same US protocol.ResultsWith regard to extrinsic carpal ligaments, the radioscaphocapitate ligament (partially visible, 38%; completely visible, 62%), the radiolunotriquetral ligament (partially visible, 27%; completely visible, 73%), the palmar ulnotriquetral ligament (partially visible, 12%; completely visible, 88%), and the dorsal radiotriquetral ligament (partially visible, 7%; completely visible, 93%) were visualized at US. The dorsal ulnotriquetral ligament (partially visible, 21%; completely visible, 74%), the ulnolunate ligament (partially visible, 5%; completely visible, 70%), and the radial collateral ligament (partially visible, 18%; completely visible, 12%) were more difficult to recognize. The radioscapholunate ligament was never seen. With regard to intrinsic carpal ligaments, the dorsal (partially visible, 11%; completely visible, 89%) and palmar (partially visible, 38%; completely visible, 62%) scaphotriquetral ligaments as well as the dorsal scapholunate ligament (partially visible, 3%; completely visible, 97%) were visualized at US. The dorsal lunotriquetral ligament (partially visible, 39%; completely visible, 61%) and the palmar scapholunate ligaments (partially visible, 12%; completely visible, 81%) were more difficult to recognize.ConclusionUS may be helpful in identifying the major extrinsic and intrinsic carpal ligaments.

Anatomic Study of the Superficial Peroneal Nerve Using Sonography

OBJECTIVE The purpose of our study was to show that sonography allows precise assessment of the location and course of the superficial peroneal nerve and of its relationship with other structures. MATERIALS AND METHODS This study, initially undertaken in cadavers, was followed by sonographic studies of 30 healthy adult volunteers (60 legs) by two radiologists in consensus. The location and course of the superficial peroneal nerve and its relationship with the adjacent anatomic structures were analyzed. RESULTS The entire course of the superficial peroneal nerve could be identified using sonography. The level at which the superficial peroneal nerve emerges between the peroneus longus and extensor digitorum longus muscles and the level at which it pierces the crural fascia and becomes subcutaneous were found to be highly variable. The superficial peroneal nerve was found to be located in the anterior compartment in 26.7% of the legs and to divide before piercing the crural fascia in 6.7% of the legs. CONCLUSION The superficial peroneal nerve can be clearly depicted by sonography. Knowledge of the nerves precise location, which may show individual variations, may have useful clinical applications.

Origin and make up of the human sural nerve

Abstract The dissection of 37 cadavers has shown that in only a third of cases, the sural nerve comes from the communication between the medial cutaneous nerve, derived from the tibial nerve, and the communicating branch of the lateral cutaneous nerve of the leg which comes from the lateral popliteal nerve. The communication is most often at the junction between the proximal two-thirds and distal third of the leg, on average 2 mm below the transverse crease of the popliteal fossa. The medial cutaneous nerve was absent in only one case. On the other hand, in 11 cases the lateral cutaneous nerve or its communicating branch was missing. In 12 cases without any anastomoses, the route of the sural nerve was followed by the medial cutaneous nerve of the leg in 9 cases and by the lateral cutaneous nerve in 3 cases. The majority of branches to the proximal half of the calf came from the lateral cutaneous nerve. In the lower part of the leg, the sural nerve and/or the medial cutaneous nerve gave numerous branches to the Achilles’ tendon and to the integuments of the lateral aspect of the heel and lateral malleolus.

High-Frequency Ultrasonographic Examination of the Finger Pulley System

The purpose of this study was to determine the ability of high‐frequency ultrasonography to provide for direct evaluation of the annular and cruciform finger pulley system.

Ultrasonographic Assessment of Arterial Cross-sectional Area in the Thoracic Outlet on Postural Maneuvers Measured With Power Doppler Ultrasonography in Both Asymptomatic and Symptomatic Populations

Objective. The purpose of this study was to evaluate the feasibility and potential usefulness of power Doppler ultrasonography (PDU) in the assessment of changes in arterial cross‐sectional area in the thoracic outlet during upper limb elevation. Methods. Forty‐four volunteers and 28 patients with a clinical diagnosis of arterial thoracic outlet syndrome were evaluated by B‐mode imaging and PDU. Arterial cross‐sectional area was assessed in the 3 compartments of the thoracic outlet with the arm alongside the body and at 90°, 130°, and 170° of abduction. The percentage of arterial stenosis was calculated for each of these arm positions. Nineteen of the 28 patients were also assessed by magnetic resonance (MR) imaging. Results. No significant arterial stenosis was shown in the interscalene triangle and in the retropectoralis minor space of the volunteers and patients. A significant difference (P < .01) in stenosis between volunteers and patients was seen for all degrees of abduction in the costoclavicular space. The 130° hyperabduction maneuver appeared to be the most discriminating postural maneuver. Seven patients assessed with MR imaging did not have any arterial stenosis on MR images, whereas an appreciable degree of arterial stenosis was shown with ultrasonography. Conclusions. Arterial compression inside the thoracic outlet can be detected and quantified with B‐mode imaging in association with PDU.

Sonographic assessment of the lateral femoral cutaneous nerve.

To evaluate the ability of high‐frequency sonography to evaluate the lateral femoral cutaneous nerve (LFCN).

Imaging features of musculoskeletal involvement in systemic sclerosis

This article describes the radiographic, sonographic and magnetic resonance (MR) features of musculoskeletal involvement in patients with systemic sclerosis (SSc). Conventional radiography is the traditional method of detecting digital calcifications, but ultrasonography (US) is also able to detect such calcifications before they appear on radiographs. MR imaging can be used to diagnose overlapping conditions (i.e., SSc and myositis or SSc and rheumatoid arthritis), and less frequently, to reveal neurologic complications of SSc. In patients with vascular ulcers, MR angiography is able to depict decreased flow within collateral digital arteries.