Evaluation of the plantaris tendon: cadaver anatomy study with ultrasonographic and clinical correlation with tennis leg injury in 759 calves.

OBJECTIVE: The role of the plantaris muscle (PM) in the literature is not clear. The objectives of this study were as follows: (1) to study PM at the interface between the medial gastrocnemius and soleus muscle in a cadaveric series, (2) to compare anatomic results with ultrasound (US) in the general population, and (3) to identify the potential role of the PM in the genesis of tennis leg (TL) injury. METHODS: First, a cadaveric study was undertaken on six cadavers for descriptive and functional PM anatomy. Second, US evaluation was carried out for 670 calves in 335 subjects with no suspicion of a clinical tear in the thigh or calf muscle (group 1) and for 89 calves in 89 patients with tear symptoms (group 2). Study criteria were the presence or absence of PM tendon and the width measurement if present. RESULTS: The PM was present in all cadavers. Traction on the tendon showed its "limited" mobility due to the connective tissue adherence mentioned with no apparent gliding of PM, promoting TL injury. In US, 37 PM were absent (4.35%) in 23 subjects. PM tendon width measurement of group 1 and group 2 was, respectively, 3.93 + / - 1.10 mm and 3.96 + / - 1.10 mm. No statistically significant differences between width measurements were found according to side (P = 0.74) or group (P = 0.69). Significant differences in width were only found between genders in group 1 (P = 0.014). CONCLUSION: PM were absent in 4.35% population. The contraction of PM can promote tennis leg injury by increasing the shear forces at the level of the distal inter-aponeurotic region.

Impact of the rise of artificial intelligence in radiology: What do radiologists think?

PURPOSE: The purpose of this study was to assess the perception, knowledge, wishes and expectations of a sample of French radiologists towards the rise of artificial intelligence (AI) in radiology. MATERIAL AND METHOD: A general data protection regulation-compliant electronic survey was sent by e-mail to the 617 radiologists registered in the French departments of Nord and Pas-de-Calais (93 radiology residents and 524 senior radiologists), from both public and private institutions. The survey included 42 questions focusing on AI in radiology, and data were collected between January 16th and January 31st, 2019. The answers were analyzed together by a senior radiologist and a radiology resident. RESULTS: A total of 70 radiology residents and 200 senior radiologists participated to the survey, which corresponded to a response rate of 43.8% (270/617). One hundred ninety-eight radiologists (198/270; 73.3%) estimated they had received insufficient previous information on AI. Two hundred and fifty-five respondents (255/270; 94.4%) would consider attending a generic continuous medical education in this field and 187 (187/270; 69.3%) a technically advanced training on AI. Two hundred and fourteen respondents (214/270; 79.3%) thought that AI will have a positive impact on their future practice. The highest expectations were the lowering of imaging-related medical errors (219/270; 81%), followed by the lowering of the interpretation time of each examination (201/270; 74.4%) and the increase in the time spent with patients (141/270; 52.2%). CONCLUSION: While respondents had the feeling of receiving insufficient previous information on AI, they are willing to improve their knowledge and technical skills on this field. They share an optimistic view and think that AI will have a positive impact on their future practice. A lower risk of imaging-related medical errors and an increase in the time spent with patients are among their main expectations.

Contribution of arthroscopy to the treatment of intraarticular fracture of the distal radius: Retrospective study of 40 cases.

Our study aimed to compare the anatomical result after treatment of intraarticular distal radius fracture with locking volar plates with and without arthroscopy. This was a retrospective, single-center study of intraarticular fractures. A volar locked plate was used for fracture fixation in all patients. Twenty patients were operated on with fluoroscopy only ("plate" group) and 20 operated using arthroscopy assistance ("arthroscopy" group). All patients underwent a CT scan before surgery and at 3 months postoperative. The main outcome measure was the residual intraarticular step-off (measured in millimeters). Other studied outcomes were the residual gap between fragments and extra-articular reduction. The two groups were similar preoperatively in all aspects except the size of the gap between fragments. The residual step-off was significantly less in the arthroscopy group: 1.9mm (Q1 1.7; Q3 2.25) for plate versus 0.8mm (Q1 0.7; Q3 1.5) for arthroscopy (P=0.001). The change from the preoperative to the postoperative measurement was significantly greater in the arthroscopy group: 0.1 mm (Q1 -0.5; Q3 0.8) for plate and -1mm (Q1 -1.9; Q3 -0.6) for arthroscopy (P=0.0002). The residual gap was similar between both groups: 2.4mm (Q1 1.9; Q3 3.5) for plate vs. 2.3mm (Q1 1.1; Q3 2.8) for arthroscopy (P=0.37). The change in gap was not significantly different between the two groups: -0.9mm (Q1 -1.8; Q3 -0.1) for plate vs. -2.9mm (Q1 -4.4; Q3 -1.7) for arthroscopy (P=0.32). There was no difference in the extra-articular reduction. Damage was found to the scapholunate ligament in 30% and the TFCC in 30% of arthroscopy cases. Arthroscopy improves intraarticular reduction without altering extra-articular reduction in patients with intraarticular fractures of the distal radius, and it allows for assessment and treatment of any injuries discovered. We must now follow these patients over the long-term to assess the clinical benefit. LEVEL OF EVIDENCE: 3.

Prospective observational study of midtarsal joint sprain: Epidemiological and ultrasonographic analysis.

INTRODUCTION: Foot and ankle injuries (FAI) are very common, with about 6000 cases per day in France. Unlike lateral ankle sprain (LAS), the diagnosis of midtarsal joint sprain (MJS, also known as Chopart's joint sprain) is not widely known. This prospective study aims to detail the epidemiology of MJS and compare it to LAS. PATIENTS AND METHOD: The study was conducted within our institution over a period of 16 months. Patients with clinical signs predictive of MJS without radiographic bone lesion underwent ultrasound assessment. MJS was diagnosed in case of at least 1 lesion of the dorsal midtarsal joint ligaments. RESULTS: A total of 2412 patients consulted for FAI; 188 had clinical and radiographic criteria for ultrasound examination. Eighty-two cases of MJS were diagnosed (3.4% of FAIs). Sports injuries were more frequent in MJS (P=0.04), and mechanisms more varied than in LAS, with inversion injury in 75% of cases and plantar hyperflexion in 22%. Sprain was severe in 70% of cases, with complete ligament tear. Clinical and ultrasound analyses correlated in only 40% of cases of MJS, versus 98% for LAS. CONCLUSION: MJS is frequent, difficult to diagnose clinically, and often severe. Clinical presentation and injury mechanisms differ from ankle sprain. Ultrasound seems to be an indispensable tool in diagnosis.

An anatomical study of the indirect tendon of the rectus femoris using ultrasonography.

UNLABELLED: The aim of this study was to demonstrate that ultrasound can allow a precise assessment of the indirect tendon of the rectus femoris using a new lateral approach. METHODS AND MATERIALS: Four hips were dissected for the anatomical study of the proximal rectus femoris insertions. Under ultrasonographic guidance, spinal needles piercing the direct tendon were placed in the indirect tendon, following by dissection. Then, high-resolution ultrasound was performed in 20 volunteers with assessment of the indirect tendon of the rectus femoris. RESULTS: At dissection, the spinal needles were located in or immediately adjacent to the indirect tendon, thus confirming that it was correctly depicted by ultrasound. The indirect tendon could be identified in each cadaver and each volunteer with ultrasound. The optimal position of the probe to allow assessment of the indirect tendon could be defined. No significant changes in the appearance or thickness of the tendon could be observed. CONCLUSION: The results of our study showed that the indirect tendon of the rectus femoris muscle can be clearly depicted by sonography in healthy adult subjects. The potential applications of this new use of sonography must now be confirmed by clinical studies. KEY POINTS: • The anatomy of the proximal rectus femoris is reviewed • Until now, sonography was limited for assessing direct and conjoined tendons • The indirect tendon can be clearly depicted by sonography • A new lateral approach for studying the indirect tendon is described.

Pisotriquetral joint disorders: an under-recognized cause of ulnar side wrist pain.

Pisotriquetral joint disorders are often under-recognized in routine clinical practice. They nevertheless represent a significant cause of ulnar side wrist pain. The aim of this article is to present the main disorders of this joint and discuss the different imaging modalities that can be useful for its assessment.

Ultrasonography of the brachial plexus, normal appearance and practical applications.

Ultrasound examination of the brachial plexus, although at first sight difficult, is perfectly feasible with fairly rapid practical and theoretical training. The roots are accurately identified due to the shape (a single tubercle) of the transverse process of C7 in the paravertebral space, and the superficial position of C5 in the interscalene groove. The téléphérique technique allows the roots, trunks and cords to be followed easily into the supraclavicular fossa. In just a few years, ultrasound imaging of the plexus has become a routine anesthesia examination for guiding nerve blocks. In trained hands, it also provides information in thoracic outlet syndromes, traumatic conditions (particularly for postganglionic lesions) and tumoral diseases. Even if MRI remains the standard examination in these indications, ultrasound, with its higher definition and dynamic character, is an excellent additional method which is still under-exploited.

Anatomic and CT scan assessment of Teres Minor: a new index of trophicity.

INTRODUCTION: The present study reports the development of a CT assessment protocol for Teres Minor (TM) trophicity. HYPOTHESIS: Quantitative reproductible Terres Minor assessment on CT estimates the influence of muscle trophicity on the clinical and radiological results of palliative treatment of irreparable rotator cuff tear. MATERIALS AND METHOD: An anatomic study of 30 cadaveric shoulders confirmed a constant anatomic relation between Terres Minor and the inferior pole of the glenoid cavity. This landmark was used to develop a novel CT assessment of TM trophicity. RESULTS: The CT assessment showed excellent inter- and intra-observer reproductibility. The protocol defines a trophicity index, T2/G (T2 being TM thickness on axial CT slice, and G the maximum glenoid cavity thickness on axial slice), enabling reproductible TM analysis on preoperative arthro-CT. CONCLUSION: The study validated the CT protocol, allowing application in pre- and postoperative assessment of irreparable rotator cuff tear. LEVEL OF EVIDENCE: Level IV. Retrospective study.

Imaging of the nerves of the knee region.

Peripheral neuropathies are a frequent, but often underdiagnosed, cause of pain and functional impairment. The clinical symptoms can be subtle, and other neurologic or non neurologic clinical entities are often evoked. MRI and ultrasonography are the imaging modalities of choice for depicting nerves and assessing neuropathies. Common neuropathies in the knee area involve the saphenous, the tibial, the common peroneal and the sural nerves. The most frequent mechanisms of nerve injury in this area are nerve entrapment and nerve stretching. A perfect knowledge of the normal imaging anatomy is essential for accurate assessment of neuropathies. In this article, we will review the anatomy of the nerves around the knee, and their normal and pathological appearance.

Radiographic anatomy of the intervertebral cervical and lumbar foramina (vessels and variants).

The intervertebral foramen is an orifice located between any two adjacent vertebrae that allows communication between the spinal (or vertebral) canal and the extraspinal region. Although the intervertebral foramina serve as the path traveled by spinal nerve roots, vascular structures, including some that play a role in vascularization of the spinal cord, take the same path. Knowledge of this vascularization and of the origin of the arteries feeding it is essential to all radiologists performing interventional procedures. The objective of this review is to survey the anatomy of the intervertebral foramina in the cervical and lumbar spines and of spinal cord vascularization.

Experimental study of the expansion dynamic of 9 mm Parabellum hollow point projectiles in ballistic gelatin.

We study in this paper the expanding behaviour of hollow point 9 mm Parabellum projectiles (Hornady XTP(®) and Speer Gold Dot(®)). We defined a deformation rate that takes into account both the diameter increase and the length reduction. We plotted the behaviour of this parameter versus impact velocity (we refer to this curve as the expanding law). This expanding law has been plotted for different gelatin weight ratios and different gelatin block lengths. We completed our experiments with a set of high speed movies in order to correlate the deceleration to the state of expansion and size of the temporary cavity. Our results pointed out that full expansion is reached shortly after the projectile fully penetrates the gelatin. This result shows that the key point to accurately simulate human body interaction with a hollow point projectile is to accurately simulate the interface (skin, skull, clothes thoracic walls). Simulating accurately organs is only an issue if a quantitative comparison between penetration depths is required, but not if we only focus on the state of expansion of the projectile. By varying the gelatin parameters, we discovered that the expanding law exhibits a velocity threshold below which no expansion occurs, followed by a rather linear curve. The parameters of that expanding law (velocity threshold and line slope) vary with the gelatin parameters, but our quantitative results demonstrate that these parameters are not extremely critical. Finally, our experiments demonstrate that the knowledge of the expansion law can be a useful tool to investigate a gunshot in a human body with a semi-jacketed projectile, giving an estimation of the impact velocity and thus the shooting distance.

[Osseous vascular anatomy in the hand and wrist]. / Anatomie vasculaire osseuse à la main et au poignet.

The design and the realization of vascularized osseous grafts at the hand and the wrist require a precise knowledge of the general and regional anatomy. This article gives first a progress report on current knowledge about the general organization of arterial and venous vascularization, of the long bones (number and localization of the nutrient foramina, communication between the epiphyseo-metaphyseal and diaphyseal networks) and of the short bones, in the adult and the child, before the closing of the growth plate. The general organization of arterial vascularization of the hand and the wrist is pointed out, with the current nomenclature and the contribution of the recent publications, in particular in these, which relate to the distal extremity of the radius. The vascularization of each bone (radius and ulna, carpal bones, metacarpals and phalanges) is then described; making way, the anatomical bases of each vascularized bone graft, which can be harvested there, are described. The last technical projections are included, in particular the realization of the reverse flow vascularized bone grafts harvested from the metacarpals. This article still gives a progress report on the osseous vascularization of the short bones, in particular of those which are exposed the most to the osteonecrosis (scaphoid, lunatum). It has the ambition to light the reader and to prepare him (her) with the reading of the following chapters.

[Spinal infections: typical and atypical imaging features]. / Infections rachidiennes: aspects typiques et atypiques.

While the imaging features of established spondylodiscitis are well known, other presentations may be misleading. The purpose of this article is to review the typical imaging features of spondylodiscitis as well as some more atypical and unusual imaging features (early spondylodiscitis, sceptic spondylitis, septic arthritis of facet joints, primary epidural abscess, unusual germs, neonate).

[Ultrasound evaluation of the greater occipital nerve]. / Démonstration échographique du nerf grand occipital.

PURPOSE: To demonstrate the appearance of the greater occipital nerve on ultrasound. MATERIALS AND METHODS: The greater occipital nerve was evaluated in 21 patients (9 males-12 females; mean age=52 years, range: 20-71; mean weight=74.5kg, range: 50-125) at the time of carotid duplex ultrasound. All examinations were preformed by the same sonographer using a single ultrasound unit. The anatomical landmark used to locate the nerve was the inferior obliquus capitis muscle. MRI and CT images were available in two cases and anatomical cadaver sections were also available. RESULTS: The greater occipital nerve could be identified at the level of the inferior obliquus capitis muscle in 90.47% (19/21) of cases, even in obese patients. In three slender patients (14.38%), the nerve could be identified at the level of the trapezius aponeurosis and next to the V3 segment of the vertebral artery. The mean anteroposterior diameter of the nerve at the level of the inferior obliquus capitis muscle was 1.65mm (range: 1.14mm-2.8mm). CONCLUSION: The greater occipital nerve could be detected at the level of its first genu by ultrasound in 90% of patients, even in obese patients.

[Value of imaging in posterolateral corner injuries of the knee]. / Apport de l'imagerie dans les lésions du point d'angle postéro-latéral du genou.

Lesions of the posterolateral corner are usually post-traumatic in etiology. They are most frequently associated with tear of the ACL and/or PCL. When unrecognized, they may lead to short-term failure of cruciate ligament reconstruction or long-term knee joint degeneration. Early detection of such lesions, especially in the preoperative period, is important since more severe injuries usually require dedicated early surgical management. The anatomy of the posterolateral corner will be reviewed and the normal and abnormal imaging features on MRI and US will be illustrated. The main clinical and surgcal features will also be presented.

[Plain radiographs of the wrist and hand]. / Les radiographies simples du poignet et de la main.

The purpose of this review is to describe the value of the different radiographic projections of the wrist and hand, provide criteria for quality control and key interpretation points. Plain radiographs of the hand and wrist are still, in this era of cross-sectional imaging, of great importance in the assessment and understanding of bone and joint disorders, particularly in the setting of trauma. Indeed postero-anterior and lateral views have to be completed with additional projections depending on the suspected lesion and clinical presentation.

Anatomical bases of tibial neurotomy for treatment of spastic foot.

Spastic pes equines, possibly associated with varus posture or spastic claw of the toes, can require neurosurgical treatment. In these cases, a selective fascicular neurotomy can be proposed, which consists of a partial section of some motor collateral branches of the tibial nerve. In order to avoid sensory and trophic complications after surgery due to an excessive manipulation of the nerve, accurate anatomical data must be collected. Therefore, biometric, histological and ultrastructural studies were carried out. A total of 50 dorsal compartments of the leg were dissected. The distance between the emergence of each muscular branch of the tibial nerve and anatomical landmarks were measured. Complementary histological study was processed on three specimens with slices stained by Masson's trichromatic method. Eventually, electronic microscopy observation was processed on two other specimens. In 16 cases (32%), we found a common muscular branch for all the muscles of the dorsal leg compartment, which emerged from the nerve trunk near the tendinous arch of the soleus (67 +/- 29 mm from the femorotibial articular line). In the other cases, muscular branches of the nerve emerged from its ventral lateral aspect, with variable origins (inferior nerve for the soleus: 82 +/- 31 mm from the femorotibial articular line, nerve for flexor digitorum longus: 116 +/- 41 mm, nerve for tibialis posterior: 106 +/- 51 mm, with a second nerve in 9/50 cases, nerve for flexor hallucis longus: 129 +/- 48 mm, with a second nerve in 6 cases). Histological and ultrastructural analysis confirmed the presence of the motor nervous fibers in the ventral lateral part of the nerve trunk. These new anatomical findings allow a more precise dissection during operative procedure, in order to avoid sensory or trophic complications.

In vivo MR tractography of thigh muscles using diffusion imaging: initial results.

The aims of this preliminary study were (1) to demonstrate the feasibility of providing in vivo 3D architecture of human thigh muscles using tractography on a 1.5T magnet, and (2) to assess the value of tractography images to obtain averaged microstructural parameters, i.e., the fractional anisotropy (FA) and the mean apparent diffusion coefficient (ADC), over the whole thigh. Five healthy volunteers were included in this study. Their right thighs were imaged using diffusion tensor imaging and gradient-echo T2* sequences. Muscular tractography was performed on each muscle. MR tractography provided a good approach of the muscle shape and of the orientation of the muscle fibers. There was no aberration in the color-encoding scheme nor in the luminosity assigned to each fiber. In contrast, tendons were not drawn in any of the muscles studied. FA values ranged from 0.27 to 0.38. Mean ADC values ranged from 0.76 to 0.96 x 10(-3) mm2/s. Our study demonstrated the feasibility of providing in vivo 3D architecture of human thigh muscles using tractography on a 1.5T magnet, and of determining muscular microstructural parameters (FA and ADC). Musculoskeletal radiologists should be aware of these new developments that may provide complementary information on muscles to the usual sequences.

Ultrasound of the nerves of the knee region: Technique of examination and normal US appearance.

The diagnosis of disorders of the peripheral nerves (PN) has traditionally been based on clinical and electrophysiological data since nerve tissue cannot be visualized on standard radiographs. More recently, however, nerve structures have been evaluated with magnetic resonance imaging (MRI) and ultrasound (US). The former modality is expensive and not available in all institutions. There are also some contraindications to its use, and the assessment of long nerves can be time-consuming since different coils must be used. Thanks to recent advances in sonographic software and hardware, US can now be used for in-depth assessment of the PN of the upper and lower limbs.Most knee disorders involve lesions to the cruciate ligaments and/or the menisci, which are difficult to evaluate with US. However, similar symptoms may be caused by compression of one or more nerves in the knee region or intrinsic disorders involving these structures. Because of their superficial positions, the nerves around the knee can be clearly visualized with US. A thorough knowledge of the normal anatomy of this region and a careful scanning technique are essential for a successful diagnostic US examination. In this article, we will review the normal gross and microscopic anatomy of the nerves in the knee region, the US technique used for their examination, and their normal US appearance.