Comparison of the anatomical dimensions and mechanical properties of the dorsoradial and anterior oblique ligaments of the trapeziometacarpal joint

PURPOSE

The respective roles of the dorsoradial (DRL) and anterior oblique (AOL) ligaments in stability of the highly mobile trapeziometacarpal (TMC) joint remain disputed. Earlier publications have pointed to the AOL as the key stabilizing structure; yet, more recent publications have challenged the stabilizing role of the AOL, favoring the DRL as the main TMC joint stabilizer. We executed an anatomical study of the ligaments, including detailed dissection to quantify the length, width, and thickness of the AOL and DRL and tested the material properties of these ligaments.

METHODS

Thirteen fresh frozen cadaveric thumbs from 9 specimens were used. Length, width, and thickness of the AOL and DRL were measured on magnetic resonance imaging and/or after dissection. Next, the first metacarpal and trapezium were isolated together with both ligaments, and both bones were cut sagittally to isolate a first metacarpal-AOL-trapezium and first metacarpal-DRL-trapezium complex from each thumb. These samples were subjected to cyclic loading in displacement-controlled tests. The obtained force-displacement curves were used to calculate stiffness and hysteresis of each sample.

RESULTS

Our results showed that the DRL is significantly shorter and thicker than the AOL, which is thin and ill-defined. Our results also indicate that the DRL has a higher stiffness than the AOL, making it a more likely candidate to provide joint stability.

CONCLUSIONS

Although the AOL has been asserted to be the primary restraint to dorsoradial subluxation, this view has been challenged over the past 10 years by several studies. These studies have shown the AOL to be relatively weak and compliant compared with the intermetacarpal and dorsoradial ligaments and have demonstrated that the DRL is the strongest and stiffest ligament of the TMC joint. Our studies confirm these findings.

CLINICAL RELEVANCE

This study indicates that the DRL is relatively stiff and thick, suggesting it should be repaired or reconstructed when disrupted to restore stability of the TMC joint.

Abstract P1-13-05: A prospective study to evaluate joint changes by ultrasound and magnetic resonance imaging induced by adjuvant chemotherapy followed by aromatase inhibitors in postmenopausal early breast cancer patients developing G3 arthralgia

Introduction: Aromatase inhibitors (AI) are a well-established component of the adjuvant hormonal therapy in postmenopausal (PM) EBC patients (pts). AI have been associated with joint symptoms in 20 to 40% of pts adversely affecting quality of life and compliance. The subjective nature of these toxicities warrants objective correlates. In this study we have compared synovial changes on MRI with ultrasound (US).

Aim of the study: The primary aim was to assess joint changes in PM EBC pts by MRI and US at baseline and at occurrence of arthralgia G3 during AI therapy. The secondary aim was to investigate the relationship between clinical severity of articular symptoms and markers of bone metabolism.

Methods: PM EBC pts, stages I-III, with a grade 0, 1 arthralgia (CTCAE version 4.0) at baseline were recruited for the study. At baseline and at 3, 6, 9, 12 and 18 months (mths) a rheumatologic questionnaire was performed. At the same time points serum samples for bone markers (Ca, ostase, intact PTH, alkaline phosphatase and vit. D), rheumatoid factor (RF) and urine samples for urinary N-telopeptide (uNTX) were taken. Pain was assessed by the Visual Analog Scale (VAS). Before start of AI, osteoarthritis was quantified by plain radiography (hands, wrists and knees), joint changes were assessed baseline and at occurrence of arthralgia G3 by MRI and US (hands and wrists), and bone density by DEXA.

Results: 29 evaluable PM EBC pts were included in the study. At baseline, 60% of the pts had a mean VAS score of 2 (0/10-5/10), which increased to 2.5 after the adjuvant chemotherapy and to 4.5 (0-8) at mth 12 (p = 0.013) of AI therapy, and subsequently dropped to 2.5 at mth 18 (p = 0.2). The most commonly affected joints at baseline were knees (47%), shoulders (41%), and ankles/feet (29%); whereas during AI therapy it involved mainly knees (53%), shoulders (46%) and hands/wrists (32%). Fifty percent of the pts had signs of osteoarthritis of the hands (25%), knees (16%) and both (8%) on plain radiographs obtained at baseline. Grade 0-1 arthralgia was not significantly correlated with the imaging of osteoarthritis or grade of osteoporosis. At baseline intra-articular fluid was detected on MRI of the hands/wrists in 6 pts, 14 pts had synovial changes and 4 had both. Six out of 29 pts had also signs of synovitis with hyperaemia on US before the start of an AI. G3 arthralgia occurred in five pts of which only three agreed to the repeat radiological imaging. In two of these pts a worsening of imaging both by MRI and US was observed, whereas in the third pt imaging was unchanged.

Markers of bone metabolism and uNTX did not differ significantly between groups with arthralgia and without (p>0.05). RF was positive in only two pts, one with arthralgia G1 at baseline and one pt at the moment of G3 arthralgia.

Conclusions: This study is the first to prospectively report on synovial changes by combined MRI and US before initiation of adjuvant AI in PM women and at occurrence of arthralgia G3. Only 17% of pts developed G3 arthralgia which corresponded to worsening imaging signs. From the small sample size it seems that baseline MRI changes predicts the development of G3 arthralgia with higher sensitivity than baseline US. Sensitivity of US improved during AI therapy.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P1-13-05.

Tuberculous arthritis of the finger: a forgotten disease

We present a case of a 64-year-old man from Belgian origin with a chronic painful swelling of the third finger. A chronic arthritis from atypical germ was suspected at the third metacarpo-phalangeal joint on the plain radiography, ultrasonography and MR examination. A few months later, he developed thoracic back pain. Plain radiographs, a Technetium-99m bone scan and MR examination of the thoracic spine revealed a spondylodiscitis of the dorsal spine. A tuberculous origin was found on the biopsy of the affected dorsal vertebral bodies D9 and D10 as suspected on the first imaging examinations of the finger. Besides the patient was found to be HIV-positive. This case shows that it is important to think of musculoskeletal tuberculosis particularly in high-risk persons because if left untreated, it can be devastating.

A pictorial overview of ultrasound of tendon disorders

A variety of terms that is often confusing is used to describe tendon changes at ultrasound.The classification of tendon disorders is often based on a combination of clinical and imaging findings. We present an overview of different categories of tendon disorders where ultrasound may contribute to the diagnosis and classification. We suggest the following categories: overuse, traumatic, inflammatory, and metabolic.The differentiation is not always possible and the importance of clinical data must be taken into account.The spectrum of tendon abnormalities is illustrated with clinical examples.

The effectiveness of diagnostic imaging methods for the assessment of soft tissue and articular disorders of the shoulder and elbow

There are no clear guidelines for diagnostic imaging of articular and soft tissue pathologies of the shoulder and elbow. Several methods are used, including magnetic resonance imaging (MRI), magnetic resonance arthrography (MRA) and ultrasound (US). Their cost-effectiveness is still unclear. We performed a meta-analysis of the relevant literature and discussed the role of MR imaging of the shoulder and elbow compared with other diagnostic imaging modalities. For the shoulder impingement syndrome and rotator cuff tears, MRI and US have a comparable accuracy for detection of full-thickness rotator cuff tears. MRA and US might be more accurate for the detection of partial-thickness tears than MRI. Given the large difference in cost of MR and US, ultrasound may be the most cost-effective diagnostic method for identification of full-thickness tears in a specialist hospital setting (Evidence level 3). Both MRA and CT arthrography (CTA) are effective methods for the detection of labrum tears. More recently, multidetector CTA has offered the advantages of thinner slices than with MRA in a shorter examination time. Still, MRA has the advantage towards CTA to directly visualize the affected structures with a better evaluation of extent and location and to detect associated capsuloligamentous injuries. For the elbow pathologies, plain MRI or MRA have the advantage towards CTA to detect occult bone injuries. CTA is better for the assessment of the thin cartilage of the elbow. Both US and MRI are reliable methods to detect chronic epicondylitis; US is more available and far more cost-effective (Evidence level 2). MRA can differentiate complete from partial tears of the medial collateral ligament. US or MRI can detect partial and complete biceps tendon tears and/or bursitis. MRI can provide important diagnostic information in lesions of the ulnar, radial, or median nerve.

MRI of cartilage and subchondral bone injury. A pictorial review

In this article, we present an overview of various cartilage and subchondral bone abnormalities seen on MRI. Injury of bone is often associated with cartilage damage and vice versa. A number of common conditions affecting joints typically show certain combinations of chondral and subchondral changes.

MR imaging findings in patients with a surgically significant mediopatellar plica

PURPOSE

To identify MR imaging findings seen in patients with an arthroscopically confirmed significant plica.

MATERIALS AND METHODS

MR and arthroscopy reports of 450 patients were reviewed. Nine patients were identified with an arthroscopically significant plica that was resected. Nine patients from these 450 were randomly chosen as a control group. Different criteria were evaluated on the MR images of all patients including: interposition of plica, number of slices with interposition, presence of fluid (focal or generalized), and thickening of the plica.

RESULTS

Interposition was found on 3 to 10 transverse imaging slices in the study group (mean, 5.9), and 1 to 4 imaging slices in the control group (mean, 3). Thickening was present in 4/9 patients of the study group and 2/9 patients in the control group. Focal fluid, out of proportion to fluid in the remainder of the joint was found in all patients of the study group and in none of the control group.

CONCLUSION

Interposition of the plica on more than 5 transverse slices, and focal fluid adjacent to the plica may suggest the presence of a plica that will be considered significant at arthroscopy.

An unusual case of cat-scratch disease of the knee: case report and differential diagnosis

We present a case of a 16-year-old boy with a painful swelling in the popliteal fossa, slight fever, articular and muscle pain of 3 weeks duration. Plain radiography and MR examination were performed in order to characterize the lesion. Additionally to the poorly defined mass, 2 satellite nodules were shown. Subsequent biopsy revealed a granulomatous process and 2 satellite lymphadenopathies highly suggestive of cat-scratch disease. This case shows that the differential diagnosis of a soft tissue mass of the knee should not only include tumoral processes or pseudotumoral lesions, but also granulomas from infectious or non-infectious origin. Knowledge of the patients contact with cats and the detection of skin scratches is usually the clue to the correct diagnosis.

Proceedings of the SRBR-KBVR osteoarticular section meeting of June 29, 2004 in Antwerp. Cystic adventitial disease

The purpose of this paper is to give a short review of the pathogenesis, imaging characteristics, differential diagnosis and current treatment of cystic adventitial disease.

MR imaging of the postoperative ankle

Although MRI of the ankle has become a routine diagnostic method to cope with pathologic conditions of the ankle, the literature on postoperative evaluation of the ankle by imaging is very scarce. In this short course, the basic principles on surgical reconstruction techniques of ankle ligaments and tendons will be reviewed. The value of imaging--with emphasis on MRI--in depicting postoperative complications will be discussed as well.

Imaging of semimembranosus bursitis: MR findings in three patients and anatomical study

We report on three patients with posteromedial knee pain related to semimembranosus bursitis. The semimembranosus bursa has a typical location and morphology around the central tendon of the semimembranosus muscle. These characteristics are demonstrated in patients and by dissection of the tendon and bursa in an embalmed knee specimen.

MR imaging findings of bone marrow changes in patients with cystic fibrosis

The purpose of this work was to evaluate bone marrow abnormalities in the lower limbs of patients with cystic fibrosis by means of MR imaging. Eight patients with cystic fibrosis ranging in age from 16 to 35 years (average age 25.1 years) were evaluated with MR imaging of the lower extremities. T1 weighted spin echo sequences were obtained in all patients. Pelvis, femora and tibia were imaged in the coronal plane whereas the feet were imaged in the sagittal plane. The studies were independently evaluated by two musculoskeletal radiologists. The images were not mixed with disease-free images, but the readers were completely unaware of clinical data. Distribution of haematopoietic and fatty marrow was graded on a 5-point scale. In five patients, both observers considered marrow distribution as probably or definitely abnormal relative to their age. Although our findings are very preliminary, our investigation suggests that cystic fibrosis may be added to the list of disorders in which bone marrow abnormalities may be observed.

Can bone marrow edema be seen on STIR images of the ankle and foot after 1 week of running?

PURPOSE

To evaluate whether initiation of running in sedentary individuals would lead to bone marrow edema on MR images, within the time span of 1 week.

MATERIALS AND METHODS

The feet of 10 healthy volunteers were imaged by MR imaging before and after running during 30 min a day for 1 week. The images were evaluated by consensus of 2 musculoskeletal radiologists who graded the presence of bone marrow edema on a 4-point scale. Edema scores and number of bones involved before and after running were compared statistically.

RESULTS

Edema was present on the baseline images in 3 subjects. After running edema showed an increase or was present in 5 subjects. The changes after running were statistically significant. Bones involved were the talus, calcaneus, navicular bone, cuboid bone, and 5th metatarsal.

CONCLUSION

Edema patterns can be seen in the feet of asymptomatic individuals. During initiation of running an increase of edema or development of new edema areas can be seen.

Posterolateral supporting structures of the knee: findings on anatomic dissection, anatomic slices and MR images

In this article we study the ligaments and tendons of the posterolateral corner of the knee by anatomic dissection, MR-anatomic correlation, and MR imaging. The posterolateral aspect of two fresh cadaveric knee specimens was dissected. The MR-anatomic correlation was performed in three other specimens. The MR images of 122 patients were reviewed and assessed for the visualization of different posterolateral structures. Anatomic dissection and MR-anatomic correlation demonstrated the lateral collateral, fabellofibular, and arcuate ligaments, as well as the biceps and popliteus tendons. On MR images of patients the lateral collateral ligament was depicted in all cases. The fabellofibular, arcuate, and popliteofibular ligaments were visualized in 33, 25, and 38% of patients, respectively. Magnetic resonance imaging allows a detailed appreciation of the posterolateral corner of the knee.

MR imaging of the medial collateral ligament bursa: findings in patients and anatomic data derived from cadavers

OBJECTIVE

The purpose of this work was to define the MR imaging findings of fluid collections confined to the medial collateral ligament (MCL) bursa and to correlate these findings with anatomic features shown in cadaveric specimens.

MATERIALS AND METHODS

The anatomic location of the MCL bursa was investigated by MR-anatomic correlation in seven cadaveric knees. The MR imaging studies and clinical charts of six patients with fluid collections confined to the MCL bursa were reviewed.

RESULTS

On anatomic sections, the MCL bursa was located between the superficial and deep portions of the MCL. Separate femoral and tibial compartments were seen in most specimens.

CONCLUSION

The anatomy of the MCL bursa is shown with MR imaging in cadaveric specimens and patients. Understanding the compartmentlike distribution of fluid in the MCL bursa at MR imaging allows accurate diagnosis and differentiation from other conditions.

MR imaging of meniscal cysts: evaluation of location and extension using a three-layer approach

PURPOSE

To analyze the extension of medial and lateral meniscal cysts relative to the capuloligamentous planes of the knee.

MATERIALS AND METHODS

The MR images of 32 patients with meniscal cysts were reviewed. The location and extension of the meniscal cysts with reference to the capsule and ligaments were recorded.

RESULTS

Most medial meniscal cysts were located posteromedially. Posteromedial meniscal cysts usually penetrated the capsule and were located between layer I and the fused layers II+III. From this site some extended anteriorly and then became located superficial to the superficial MCL. The location of lateral meniscal cysts was more varied. Anteriorly the cysts were located deep to the iliotibial band, whereas posterolateral cysts were located deep to the lateral collateral ligament.

CONCLUSION

Although the site of capsular penetration of meniscal cysts is determined by the location of meniscal tears, the possible pathways of extension appear to be determined by the capsuloligamentous planes of the knee.

CT and MR arthrography of the normal and pathologic anterosuperior labrum and labral-bicipital complex

Interpretation of computed tomographic and magnetic resonance arthrograms of the shoulder is complicated by normal variants of the labrum and glenohumeral ligaments. A superior sublabral recess is located at the 12 o'clock position and represents a normal recess between the superior labrum and the cartilage of the glenoid cavity. A sublabral foramen is located at the 2 o'clock position and represents localized detachment of the labrum from the glenoid rim. Buford complex is characterized by absence of the anterosuperior labrum and cordlike thickening of the middle glenohumeral ligament. Imaging features of damage to the anterior labrum include absence or detachment of the labrum and an irregular frayed appearance. Superior labrum anterior-to-posterior (SLAP) lesions are classified as type I (tear confined to the superior labrum), type II (labrum and biceps tendon detached from the superior glenoid), type III (bucket handle tear of the superior labrum), or type IV (bucket handle tear of the superior labrum with lateral extension into the biceps tendon). Increased distance between the labrum and the glenoid, an irregular appearance of the labral margin, or lateral extension of the separation may suggest a SLAP lesion rather than a normal anatomic variant. However, differentiation between normal variants and pathologic conditions and between various types of SLAP lesions remains difficult.

Subperiosteal ganglion cyst of the tibia. A communication with the knee demonstrated by delayed arthrography

We report a patient with a subperiosteal ganglion cyst of the tibia which was imaged by radiography, arthrography, CT and MRI. The images were correlated with the arthroscopic surgical and histological findings. Spiculated formation of periosteal new bone on plain radiographs led to the initial suspicion of a malignant tumour. Demonstration of the cystic nature of the tumour using cross-sectional imaging was important for the precise diagnosis. Communication between the ganglion cyst and the knee was shown by a delayed arthrographic technique, and the presence of this communication was confirmed at arthroscopy and surgically.

Subperiosteal ganglion cyst of the tibia

We report a patient with a subperiosteal ganglion cyst of the tibia which was imaged by radiography, arthrography, CT and MRI. The images were correlated with the arthroscopic surgical and histological findings. Spiculated formation of periosteal new bone on plain radiographs led to the initial suspicion of a malignant tumour. Demonstration of the cystic nature of the tumour using cross-sectional imaging was important for the precise diagnosis. Communication between the ganglion cyst and the knee was shown by a delayed arthrographic technique, and the presence of this communication was confirmed at arthroscopy and surgically.

Tarsal tunnel syndrome: ultrasonographic and MRI features

Tarsal tunnel syndrome is a well-known but rare entrapment neuropathy involving the posterior tibial nerve in the tarsal tunnel, a fibro-osseous channel extending from the medial aspect of the ankle to the midfoot. Posttraumatic fibrosis, ganglion cyst, tenosynovitis, tumor of the nerves or other structures, dilated or tortuous veins can cause significant nerve compression in this anatomic region. Herein, we present the typical ultrasonographic and magnetic resonance features of this disorder in patient with a ganglion cyst.

SLAP lesions: a retrospective multicenter study

A retrospective analysis of 530 glenohumeral arthroscopies performed by three independent Belgian arthroscopists revealed the presence of 32 SLAP lesions, which represents an incidence of 6%. Since this is exactly the same percentage as found by Snyder et al., we report our data in this article. We classified 23 of the SLAP lesions using Snyder's classification, 7 needed the additional classification of Maffet et al., and 2 lesions were considered to be anatomic variations; 53% of the lesions were of type II. Concerning the mechanism of injury, we found comparable percentages of traction (22%) and compression (28%) injury as reported by Snyder, but also a high number (25%) of overhead sports activities as described by Andrews et al. Associated lesions were in close accordance with Snyder's data, but a relatively low incidence of rotator cuff injuries (10%) was present. Comparison of treatment regimens showed that the same percentage of lesions (34%) was fixed arthroscopically in both series. Only SLAP II, IV, and V lesions must be considered as unstable and in need of fixation. We confirm that patients' complaints and clinical symptoms are vague and inconsistent. Imaging, using computed tomographic arthrography or magnetic resonance, was performed in a minority of cases. Advantages and pitfalls of both techniques are discussed. Anatomic variations causing an extra-large sublabral hole are shown, and we warn about potential diagnostic and therapeutic errors in these cases.

Calcium hydroxyapatite deposition disease of the neck: finding in three patients

Calcium hydroxyapatite deposition disease may occasionally involve the superolateral portion of the longus colli muscle. Clinical symptoms include headache, neck pain, and dysphagia. Characteristic prevertebral calcifications with the epicenter at the C1-C2 level are depicted on lateral radiographs of the cervical spine.

Glenoid dysplasia: radiographic and CT arthrographic findings

A 60-year-old man with dysplasia of the glenoid and a rotator cuff tear is reported on. Because of the tear, CT arthrography was performed, offering an opportunity to evaluate the various soft tissue abnormalities accompanying glenoid dysplasia. Marked thickening of the glenoid cartilage and labrum was apparent, as well as an abnormal posterolateral orientation of the glenoid cavity. A deep notch was observed along the central portion of the glenoid cartilage. Furthermore the middle glenohumeral ligament appeared thickened and cordlike.

Imaging in sports-medicine--knee

Since the last decade, the introduction of Magnetic Resonance Imaging has provided a powerful new tool for the clinician to diagnose sports-related knee injuries. The main objective of this paper is to familiarise the relevant specialists with the proven clinical indications and semiology of MRI of the knee. At the present time, the knee joint is the area in which the advantages of MRI are most spectacularly apparent. The MR appearances of meniscal tears in particular, are first discussed in detail, referring to recent literature and personal experience based on more than ten thousands MR examinations of traumatic knees. Also the mechanisms of injuries and the most commonly involved sports are described. The precise types of meniscal lesions, as visualised at arthroscopy, are abundantly illustrated on MR images: e.g., bucket-handle, radial and horizontal cleavage tears, meniscocapsular separations, discoid menisci and meniscal cysts. We discuss the numerous pitfalls due to neighbouring anatomical structures as well as non clinically or surgically significant intrameniscal hypersignals in athletes. Towards other imaging techniques, MRI is particularly suited for the diagnosis of ligamentous injuries, especially the cruciate ligaments. We develop the currently used direct and indirect signs of rupture, the diagnostic difficulties related to the age of trauma and the detection of associated lesions. Sport-induced tendinous and bursal pathology is another interesting indication of MRI, not only lesions of the more superficial extensor tendons but also the pes anserinus or hamstring tendons. We finally treat the recent developments of MRI in assessment of cartilage, subchondral and medullary bone disorders of traumatic or microtraumatic origin.

[A "good choice" of diagnostic imaging examinations: the knee]

A medically sound and cost-effective choice of diagnostic imaging investigations in knee pathology must be supported by a good evaluation of the respective strong and weak points of the available methods. These are: conventional radiology, C.T., arthrography, arthro C.T., ultrasound, scintigraphy and magnetic resonance imaging. Based upon that analysis, decisional algorithms are proposed, in function of the clinically suspected pathologies.

Hydroa vacciniforme treated by a combination of beta-carotene and canthaxanthin

Hydroa vacciniforme is a very rare photodermatosis, commencing in childhood and belonging to the category of idiopathic burns. The inconstancy of the therapeutic results raises the possibility of a clinical syndrome that can have different origins. We present a case that responded very well to carotenoids.

Lymphomatoid papulosis: a clinical case

We report a case of lymphomatoid papulosis in a 36-year-old man who presented recurrent necrotic skin nodules that regressed spontaneously leaving scars. The condition had persisted since 1988. These nodules were always solitary and located on the extremities. Histological examination revealed a perivascular and interstitial, superficial and deep infiltrate with numerous atypical lymphocytes (> 40%) characterized by cerebriform mononuclear cells and large atypical cells stained by MT1, UCHL1 and Ber-H2 (anti-CD30). No associated disease was found. The patient has been free of lesions for more than a year without treatment. A nosological and physiopathological hypothesis of lymphomatoid papulosis is discussed.

Femoral periosteal thickening in pustulotic arthroosteitis, including 3-year followup by magnetic resonance imaging

We describe 2 female patients with femoral periosteal thickening, in association with signs of pustulotic arthroosteitis in the sternocostoclavicular region and spine. In one patient, inflammatory changes were seen in muscular tissue surrounding this area of periosteal thickening, with fibrosis in the corresponding marrow. Over a period of up to 4 years after bone biopsy, cortical hyperostosis was observed spreading over a longer segment of her femoral diaphysis, while its thickness decreased over the longterm. Bone biopsy probably contributed to the striking periosteal thickening surrounded by inflammatory lesions in the surrounding muscles of this patients.

Osteomalacia in a patient with anorexia nervosa

A 32-year-old patient with anorexia nervosa since adolescence was admitted because of diffuse bone pain, increasing during the 2 preceding winters. She had a special aversion to dairy products and all forms of dietary fat. Low normal serum calcium and very low calciuria were noted, with a highly elevated bone fraction of alkaline phosphatase, and severe hypovitaminosis D and B12. Apart from a recent spontaneous fracture of the clavicle, Looser lines and pseudofractures were noted in a finger, fibula and malleolus. In particular, magnetic resonance imaging of the knee showed additional evidence of a pseudofracture in the femur, and medullary changes were found. Evidence for secondary hyperparathyroidism was described. Apart from the well known occurrence of osteoporosis, our case shows that osteomalacia may exceptionally occur in anorexia nervosa.

Imaging and differential diagnosis of synovial sarcoma

Synovial sarcoma is an uncommon malignant tumor, most frequent in the lower extremity, predominantly in young males. The authors review the clinical history, the different radiographic manifestations and MR appearance of the entity. The MR findings cannot be considered specific for synovial sarcoma. A heterogeneous septated mass located close to a joint, a tendon or a bursa is most indicative of the tumor. The radiographic features of a soft tissue mass with associated calcifications and bony erosions in the lower extremity should suggest a synovial sarcoma. The most likely differential diagnoses are discussed.

The accuracy of three-dimensional magnetic resonance imaging in the diagnosis of ruptures of the lateral ligaments of the ankle

In a prospective study, the diagnostic accuracy of three-dimensional magnetic resonance imaging in the evaluation of ruptures of the lateral ligaments of the ankle was determined by comparing three-dimensional magnetic resonance findings with operative findings. In a series of 18 consecutive cases of acute significant inversion trauma to the ankle, a three-dimensional fast imaging with steady-state precession pulse sequence (3D FISP) was performed. The study included only those cases in which views showed a difference in talar tilt of 15 degrees or more, and a difference in anteroposterior drawer of 10 mm or more between the imaged and the normal ankle. All ankles were scheduled for surgical exploration. Compared with operative findings, the sensitivity, specificity, and accuracy of 3D FISP imaging were, respectively, 100%, 50%, and 94.4% for ruptures of the anterior talofibular ligament and 91.7%, 100%, and 94.4% for ruptures of the calcaneofibular ligament. We believe that 3D FISP magnetic resonance imaging is a noninvasive, fast, and very accurate diagnostic aid to operative planning for double ligament tears in younger competitive athletes.

[Immunohistology of bullous autoimmune skin diseases]

Autoimmune bullous dermatoses undertake frequently oropharyngeal mucous membranes and the skin surface, either in succession or simultaneously. Actual observation technics by photon and electron microscopy, by immunofluorescence and immunohistochemistry (with specific antibodies) have allowed to differentiate more particularly pemphigus, bullous pemphigoid, cicatricial pemphigoid, acquired bullous epidermolysis, all autoimmune bullous affections.

Magnetic resonance imaging of articular destruction in juvenile rheumatoid arthritis

We describe herein magnetic resonance imaging of the right knee of a patient affected by a severe form of juvenile rheumatoid arthritis. Magnetic resonance imaging findings of articular damage of the knee during the disease course and after arthroscopic synovectomy are described.

Chondral lesions of the patella evaluated with computed tomography, magnetic resonance imaging, and arthroscopy

In a small series of cadaver knees, experimentally created lesions of the patellar cartilage were compared using contrast computed tomography (CT) and magnetic resonance (MR) imaging. Contrast CT was able to recognize only 50% of the lesions smaller than 3-mm diameter at the first attempt, and none of the lesions of 0.8 mm. MR imaging detected all the lesions, even those as small as 0.8 mm, without use of contrast material. Simultaneously, a prospective clinical study comparing MR diagnoses of chondral lesions with arthroscopic findings was initiated in a series of 54 knees. This clinical study revealed that, concerning patellar chondral lesions, the accuracy of MR imaging compared with arthroscopy (the gold standard) was 81.5%. The sensitivity was 100%, but the specificity only 50% due to the false positives. Reexamination of the MR records enabled us to refine the MR diagnosis and to propose a staging of the chondral lesions. The high rate of false-positive results in our series can be explained by the hypothesis that MR imaging can possibly detect very early lesions, which appear as abnormalities in the deep cartilage layers.

Osteoblastoma of the patella. Case report and review of the literature

Benign osteoblastoma is a rare tumor; the majority of lesions occur in the spine, femur, and tibia. Osteoblastoma in the patella is so rare that it seems not to have been reported previously in more than one case. A 29-year-old man with a sports injury, who failed to respond to conservative treatment over a prolonged period of time, was later found to have an osteoblastoma of the patella.