[Systematics of injuries of the rotator cuff and biceps tendon]. / Systematik der Verletzungen von Rotatorenmanschette und Bizepssehne.

PERFORMANCE: Injuries of the rotator cuff and the biceps tendon demonstrate different patterns, which can be recognized clinically and radiologically. ACHIEVEMENTS: These patterns are impingement syndrome with additional trauma, isolated trauma of the rotator cuff and shoulder dislocation causing rotator cuff tears. Furthermore, it is clinically crucial to evaluate the extent of a rotator cuff injury. PRACTICAL RECOMMENDATION: Magnetic resonance imaging (MRI) is the modality of choice to differentiate these patterns.

Short-term outcome of painful bone marrow oedema of the knee following oral treatment with iloprost or tramadol: results of an exploratory phase II study of 41 patients.

OBJECTIVES: To compare the therapeutic effects of oral iloprost and tramadol on the outcome of bone marrow oedema (BME) of the knee by MR imaging and clinical assessment. METHODS: Forty-one patients with painful ischemic or mechanical BME of the knee were enrolled in a double-blind, randomized controlled study. Patients were randomized either to iloprost (n = 21, group 1) or tramadol (n = 20, group 2). The treatment duration was 4 weeks. The Larson knee score was used to assess function before treatment and then 3 days, 1, 2, 3, 4 weeks and 3 months after the start of treatment. Short tau inversion recovery and T1-weighted MR images of the affected knees were obtained before and 3 months after the start of treatment. Bone marrow oedema was assessed visually and by computer-assisted quantification for baseline and follow-up MR examinations. RESULTS: Thirty-three patients completed the study as scheduled. The mean Larson score improved from 58.6 points to 81.8 points in group 1, and from 59.6 points to 86.8 points in group 2, after 3 months (no significant difference between the treatment groups). On MR images, complete BME regression in at least one bone was observed in nine patients (52.9%) in group 1, as opposed to three patients (18.7%) in group 2, after 3 months (P = 0.034). Correspondingly, the median BME volume decreased by 58.0% in group 1, and by 47.5% in group 2. CONCLUSIONS: The analgesic effect of iloprost and tramadol was similar. BME regression on MR images was more pronounced under iloprost treatment.

[Injury of the ankle joint ligaments]. / Bandverletzungen des Sprunggelenks.

The diagnosis of lateral collateral ankle ligament trauma is based on patient history, clinical examination and clinical stress tests. If the clinical stress test is positive, stress radiography can be performed. There is, however, no consensus about the usefulness of stress radiography in acute ankle sprain, and in particular about the cut-off talar tilt angle beyond which a two-ligament rupture would be certain, ranging from 5 degrees to 30 degrees. Today, magnetic resonance imaging (MRI) is not used in this area, although it does allow controlled positioning of the foot and defined section visualization of injured lateral collateral ankle ligaments. In acute and chronic sinus tarsi injuries, MRI forms the established basis for diagnostic imaging, and can provide a definitive answer in most cases. MRI is also the method of choice for chronic posttraumatic pain with anterolateral impingement after rupture of the anterior talofibular ligament. Generally, for the evaluation of acute ankle injuries, MRI has developed to be the most important second-step procedure when projection radiology is non-diagnostic.

[Differential diagnosis of bone marrow edema of the knee joint]. / Differenzialdiagnosen des Knochenmarködems am Kniegelenk.

Bone marrow edema of the knee joint is a frequent clinical picture in MR diagnostics. It can be accompanied by symptoms and pain in the joint. Diseases that are associated with bone marrow edema can be classified into different groups. Group 1 includes vascular ischemic bone marrow edema with osteonecrosis (synonyms: SONK or Ahlbäck's disease), osteochondrosis dissecans, and bone marrow edema syndrome. Group 2 comprises traumatic or mechanical bone marrow edema. Group 3 encompasses reactive bone marrow edemas such as those occurring in gonarthrosis, postoperative bone marrow edemas, and reactive edemas in tumors or tumor-like diseases. Evidence for bone marrow edema is effectively provided by MRI, but purely morphological MR information is often unspecific so that anamnestic and clinical details are necessary in most cases for definitive disease classification.

Rotator cuff tears in asymptomatic individuals: a clinical and ultrasonographic screening study.

OBJECTIVE: To determine the prevalence and clinical impact of rotator cuff tears in asymptomatic volunteers. MATERIALS AND METHODS: Sonographic examinations of the shoulder of 212 asymptomatic individuals between 18 and 85 years old were performed by a single experienced operator. The prevalence and location of complete rotator cuff tears were evaluated. The clinical assessment was based on the Constant Score. Magnetic resonance imaging (MRI) of the shoulder was obtained in those patients where US showed rotator cuff pathology. RESULTS: Ultrasound showed a complete rupture of the supraspinatus tendon in 6% of 212 patients from 56 to 83 years of age (mean: 67 years). MRI confirmed a complete rupture of the supraspinatus tendon in 90%. All patients reported no functional deficits, although strength was significantly lower in the patient group with complete supraspinatus tendon tear (P < 0.01). CONCLUSION: There is a higher prevalence in older individuals of rotator cuff tendon tears that cause no pain or decrease in activities of daily living.

[Impingement syndrome of the shoulder]. / Schulterimpingement.

The impingement syndrome is a clinical entity characterized by shoulder pain due to primary or secondary mechanical irritation of the rotator cuff. The primary factors for the development of impingement are a curved or hook-shaped anterior acromion as well as subacromial osteophytes, which may lead to tearing of the supraspinatus tendon. Secondary impingement is mainly caused by calcific tendinopathy, glenohumeral instability, os acromiale and degenerative changes of the acromioclavicular joint. Conventional radiographs are initially obtained, mainly for evaluation of the bony structures of the shoulder. If available, sonography can be used for detection of lesions and tears of the rotator cuff. Finally, MR-imaging provides detailed information about the relationship of the acromion and the acromioclavicular joint to the rotator cuff itself. In many cases however, no morphologic cause for impingement syndrome can be found. While patients are initially treated conservatively, chronic disease usually requires surgical intervention.

[MRI of the lateral ankle ligaments: value of three-dimensional orientation]. / MR-Diagnostik der lateralen Sprunggelenksbänder: Bedeutung der dreidimensionalen Orientierung.

PURPOSE: To determine the three-dimensional orientation of the lateral ankle ligaments with MRI. MATERIALS AND METHODS: Twenty healthy volunteers without previous injury to the ankle were included in the study. With the right ankle in the normal anatomic position stabilized in a splint, coronal T2-weighted spin-echo sequences (TSE) were obtained. The three-dimensional orientation was determined by placing paths through the ligaments and by measuring the angles between corresponding tangents and the three main imaging planes. RESULTS: Using the calculated angles, full-length visualization of the lateral ligaments of the ankle was achieved. The angles deviating from the axial imaging plane were 18.0 degrees for the anterior talofibular ligament, 52.3 degrees for the calcaneofibular ligament and 28.2 degrees for the posterior talofibular ligament. CONCLUSION: MRI enables the exact determination of the three-dimensional orientation of the lateral ankle ligaments. Orienting the imaging planes according to the calculated angular deviation allows the full-length visualization of the ligaments and is the basis for optimal imaging of the lateral ankle ligaments.

[Diagnostic imaging in hip prostheses]. / Bildgebung bei Hüftprothesen.

Hip arthroplasty has become a common and still increasing procedure for the treatment of osteoarthritis, advanced head necrosis, post-inflammatory arthritis or rheumatoid arthritis. Radiography is the most important imaging modality for monitoring the normal, asymptomatic hip arthroplasty. Radiographs are obtained at the end of a surgical treatment, to exclude complications like fracture or component misplacement. In the follow-up radiographs are used for the diagnosis of loosening and infection of the hip arthroplasty as well as soft tissue ossification. Together with the history and clinical information, the analysis of morphological findings allows to find the grade of loosening. MRI has been advocated in the diagnosis of infection, in particular in the localisation of soft tissue involvement. Imaging, especially by radiographs, is used for the evaluation of the normal and complicated follow-up of hip arthroplasty.

Diagnosis of occult scaphoid fractures and other wrist injuries. Are repeated clinical examinations and plain radiographs still state of the art?

To examine the efficacy of repeated clinical examinations and follow-up radiographs, 121 patients were prospectively and consecutively randomised and clinically followed until a final diagnosis was achieved. All of these patients additionally underwent magnetic resonance imaging (MRI) scans within an average of 3 days after trauma to control the results of this study. MRI detected 112 injuries in 82 patients (67%). Twenty-eight (25%) of these injuries were scaphoid fractures. There were 15 fractures of other carpal bones, 14 avulsion fractures of extrinsic ligaments (AFL), 26 other bone injuries (fractures of distal radius, fractures of radial styloid, ulnar head fracture metacarpal fracture, bone bruises), and 29 soft tissue injuries (triangular fibro-cartilaginous complex injuries, complete or partial ruptures of the scapholunate ligament, ruptures of the radial collateral ligament, hemarthrosis). By means of repeated clinical examinations and plain scaphoid views, experienced observers were able to detect all the occult scaphoid fractures within 38 days, as well as most of the other fractures about the wrist except one fracture of the triquetrum. Soft tissue injuries, however, were diagnosed only in two cases of complete scapholunate ligament tears. It was further obvious that 70% of all scaphoid fractures and 60% of the AFLs were detected in a review of the initial X-rays by experienced surgeons. Only 30% of all scaphoid fractures detected were really occult and all of these were diagnosed correctly. This prospective study demonstrates that clinical and radiological standard procedures are reliable in the diagnosis of occult fractures of the carpus and wrist when performed by experienced observers. MRI scans are indicated for early diagnosis of occult fractures and soft tissue injuries about the wrist.

[Acute ankle injuries]. / Akutes Trauma des Sprunggelenks.

The diagnosis of lateral collateral ankle ligament trauma is based on patient history, clinical examination, and clinical stress tests. If the clinical stress test is positive, stress radiography could be performed. There is no consensus about the usefulness of stress radiography in acute ankle sprain, particularly about the cut-off talar tilt angle beyond which a two-ligament rupture would be certain, ranging from 5 degrees to 30 degrees. Today MRI is not used for this indication, although it allows, with controlled positioning of the foot and with defined sections, visualization of injured lateral collateral ankle ligaments. In ankle injuries, plain radiographs form the established basis of diagnostic imaging and can provide definitive answers in most cases. CT is used in complex fractures for complete visualization. MRI is the method of choice for several diagnostic problem cases, including occult fractures and post-traumatic avascular necrosis. In tendon injuries, MRI is important if ultrasound is not diagnostic. Generally, for the evaluation of acute ankle injuries, MRI is the most important second-step procedure when radiographs are nondiagnostic.

Assessment of chronic constipation: colon transit time versus defecography.

OBJECTIVE: The aim of this study was to determine the value of radiological colon transit time (CTT) measurements in relation to defecography (DFG) in chronically constipated patients. MATERIALS AND METHODS: In 30 patients with chronic constipation, total and segmental CTT was determined using radiopaque markers. In all of these patients defecography (DFG) was obtained. The patients were divided into three groups: In group I, 11 patients were classified with idiopathic constipation based on low stool frequency, normal DFG, or absence of symptoms of abnormal defecation. In group II, ten patients with rectal intussusception were diagnosed by DFG. In group III, there were nine patients with rectal prolapse or spastic pelvic floor syndrome, based on results of DFG. RESULTS: Group I, idiopathic constipation (n = 11), showed increased total CTT (mean, 93 h) and segmental CTT (right colon, 33 h (36%), left colon, 31 h (33%), rectosigmoid, 29 h (31%)). In group II, intussusception (n = 10), patients had normal mean total CTT (54 h) and a relative decrease in rectosigmoid CTT (mean, 13 h (24%)). In group III (n =9), rectal prolapse (n = 5) or spastic pelvic floor syndrome (n = 4), patients showed elevated total (mean, 167 h) and rectosigmoidal CTT (mean, 95 h (57%)). Mean total CTT was significantly different between groups I and II and between groups II and III, and mean rectosigmoidal CTT was significantly different between all three groups (P < 0.05). CONCLUSION: The use of total and rectosigmoidal CTT helps to identify the underlying pathophysiology of chronic constipation. Furthermore CTT helps to identify patients, who may benefit from DFG.

Limited diagnostic value of macroradiography in suspected scaphoid fractures.

In a prospective study 60, patients having suspected occult scaphoid fractures, but with normal conventional scaphoid radiographs, also underwent macroradiography. Clinical and conventional radiographic follow-up examinations and MRI identified 8 occult scaphoid fractures and 23 nonscaphoid lesions. Macroradiography identified only 50% of the occult scaphoid fractures.

Alveolar rhabdomyosarcoma in a 68-year-old patient identified by cytogenetic analysis of bone marrow.

Pancytopenia and fulminant disseminated intravascular coagulation in a 68-year-old woman suggested an acute hematologic malignancy. However, cytogenetic analysis on a bone marrow sample revealed a near-tetraploid karyotype with an isochromosome 1q and a translocation (2;13) (q35;q14), which was suggestive of an alveolar rhabdomyosarcoma (ARMS). This diagnosis was subsequently confirmed by indirect immunohistochemistry. ARMS has not yet been observed in a patient of this age. Thus, our case underlines the importance of cytogenetics, to establish an a priori unexpected tumor diagnosis.

[Diagnostic reliability of 0.2 Tesla dedicated MRI low-field strength equipment in traumatology]. / Die diagnostische Sicherheit von 0.2 Tesla dedizierten MRT Niederfeldgeräten in der Traumatologie.

Anatomical dedicated low-field-strength MR imaging (non-whole-body-systems) has been developed for examinations of the peripheral joints. It has several advantages compared to high-field-strength MR imaging (whole-body-systems). The dimensions are small, the noise is not as bad as in whole body systems and people do not suffer of claustrophobic attacks. However, our results of a prospective blinded study in 56 patients with three different kinds of peripheral joint injuries demonstrated that the 0.2 T dedicated system showed a significant lower rate of diagnostic accuracy compared to middle and high-field-strength MR imaging and scored with obvious lower image quality ratings.

[Pitfalls in MRI diagnosis of primary malignant bone tumors]. / Pitfalls in der MR-Diagnostik primär maligner Knochentumoren.

MRI has gained an undisputed place in the evaluation of malignant bone tumors, not only for verifying results of conventional radiographs and clarifying differential diagnoses; it has also become increasingly important for the assessment of the malignant/benign nature of the tumor, its growth rate, definition of adequate sites for biopsy, local preoperative staging, and evaluation of the response to chemotherapy. However, several pitfalls have to be observed regarding choice of technical parameters (coils, sequences, imaging planes), tissue differentiation, and tumor staging. When staging malignant tumors, critical aspects which have to be observed are tumor extension, integrity of the cortical bone, soft tissue components, infiltration of a joint or neurovascular bundle. The use of contrast agents provides important additional information but can also give rise to misinterpretations. Thus, all features of a tumor have to be observed in order to establish a final diagnosis. Particular difficulties can occur with the interpretation of MR images of osteomyelitis, osteoid osteoma, stress and insufficiency fractures, bone infarcts, myositis ossificans, hemangiomas, and aneurysmal bone cysts.

[Prospective comparison of MRI vs. direct magnification radiography in occult fractures of the scaphoid bone]. / Prospektiver Vergleich MRT vs. direkte Vergrösserungsradiographie bei okkulten Frakturen des Os scaphoideum.

The diagnosis of occult fractures of the scaphoid bone is even more challenging than that of conventional fractures of the scaphoid. This study aimed to compare prospectively the gold standard method (plain radiographs in four projections, after about 14 days) and the primary findings with direct magnification radiography (DIMA) and magnetic resonance imaging (MRI). Primary MRI showed much higher diagnostic power than plain radiography at 10-14 days in occult scaphoid fractures and in detection of associated carpal injuries. This may lead to a decreasing time of disease. DIMA was inferior in detecting occult fractures of the scaphoid.

Imaging articular cartilage defects with 3D fat-suppressed echo planar imaging: comparison with conventional 3D fat-suppressed gradient echo sequence and correlation with histology.

PURPOSE: Our goal was to shorten examination time in articular cartilage imaging by use of a recently developed 3D multishot echo planar imaging (EPI) sequence with fat suppression (FS). We performed comparisons with 3D FS GE sequence using histology as the standard of reference. METHOD: Twenty patients with severe gonarthrosis who were scheduled for total knee replacement underwent MRI prior to surgery. Hyaline cartilage was imaged with a 3D FS EPI and a 3D FS GE sequence. Signal intensities of articular structures were measured, and contrast-to-noise (C/N) ratios were calculated. Each knee was subdivided into 10 cartilage surfaces. From a total of 188 (3D EPI sequence) and 198 (3D GE sequence) cartilage surfaces, 73 and 79 histologic specimens could be obtained and analyzed. MR grading of cartilage lesions on both sequences was based on a five grade classification scheme and compared with histologic grading. RESULTS: The 3D FS EPI sequence provided a high C/N ratio between cartilage and subchondral bone similar to that of the 3D FS GE sequence. The C/N ratio between cartilage and effusion was significantly lower on the 3D EPI sequence due to higher signal intensity of fluid. MR grading of cartilage abnormalities using 3D FS EPI and 3D GE sequence correlated well with histologic grading. 3D FS EPI sequence agreed within one grade in 69 of 73 (94.5%) histologically proven cartilage lesions and 3D FS GE sequence agreed within one grade in 76 of 79 (96.2%) lesions. The gradings were identical in 38 of 73 (52.1%) and in 46 of 79 (58.3%) cases, respectively. The difference between the sensitivities was statistically not significant. CONCLUSION: The 3D FS EPI sequence is comparable with the 3D FS GE sequence in the noninvasive evaluation of advanced cartilage abnormalities but reduces scan time by a factor of 4.

MR imaging of meniscal subluxation in the knee.

PURPOSE: The aim of this study was to establish diagnostic criteria for meniscal subluxation, and to determine whether there was any connection between meniscal subluxation and other common meniscal and knee-joint abnormalities. MATERIAL AND METHODS: The normal position of the meniscal body was assessed in 10 asymptomatic volunteers. MR signs of meniscal subluxation were evaluated retrospectively in 60 symptomatic patients with pain in the knee, impaired mobility, and/or joint swelling who had no clear diagnosis after the evaluation of case history, clinical examination, and radiography. The criterion for subluxation of the meniscus was defined as a distance of > or = 3 mm between the peripheral border of the meniscus and the edge of the tibial plateau. RESULTS: In the volunteers, the mean distance from the medial meniscus to the edge of the tibial plateau was 0.07 mm, and that from the lateral meniscus was 0 mm. In 55 symptomatic patients without meniscal subluxation, the mean distance from the meniscus to the edge of the tibial plateau was 0.27 mm. Five patients (8%) had evidence of meniscal subluxation, 4 in the medial meniscus and one in the lateral meniscus. The most commonly associated knee abnormality was joint effusion in 5 knees and osteoarthritis in 2 knees. CONCLUSION: Meniscal subluxation was not a rare finding with MR imaging in patients with painful knees. Meniscal subluxation was associated with other knee abnormalities such as joint effusion or osteoarthritis.

Trauma of the wrist.

In wrist injury, plain radiographs form the basis of diagnostic imaging, and can provide definitive answers in most cases. MR imaging is the method of choice for several diagnostic problem cases. These problems can include radiographically occult fractures where MRI enables early diagnosis compared to follow-up radiographs. Early stage diagnosis of a post-traumatic avascular osteonecrosis with high sensitivity and specificity, is only possible with MRI. In these instances, radiographs are only sensitive in later stages and scintigraphy is quite nonspecific. Stress fractures, invisible with other modalities, are also demonstrable with MRI. In addition, MRI is helpful in special circumstances with regard to non-union or pseudarthrosis. In wrist instability, radiographs in combination with stress views and fluoroscopy are still the initial diagnostic step. MRI, with the advantage of direct visualization of the wrist ligaments and triangular fibrocartilage complex, offers very promising results in this area. Generally, for the evaluation of wrist injury, MRI can be considered the most important second-step procedure in patients where radiographs are nondiagnostic.