[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.

[Arthrosis - update 2012]. / Arthrose - Update 2012.

Osteoarthritis is the most common joint disease in adults. With higher life expectancy and a growing proportion of elderly people in society, the relevance of osteoarthritis is becoming higher, especially in terms of socioeconomic effects and burdens for the healthcare system. In this review the pathogenesis and risk factors of the disease are presented with the focus on the knee, hip and shoulder, clinical symptoms, diagnosis and especially radiological imaging and therapy options.

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.

[Bone marrow edema in the knee. Differential diagnosis and therapeutic possibilities]. / Knochenmarködem im Kniegelenk. Differenzialdiagnostik und therapeutische Möglichkeiten.

The Bone marrow edema (BME) is a common finding when evaluating patients with knee pain by magnetic resonance imaging (MRI). The typical signal patterns of BME are unspecific and can be found with different diseases of the knee. Since different therapeutic approaches are mandatory, differential diagnosis of the several forms of BME is important. In this review, painful BME will be separated into three different etiological groups. Group 1 ischemic BME: osteonecrosis, osteochondritis dissecans, bone marrow edema syndrome and complex regional pain syndrome. Group 2 mechanical BME: bone bruises, microfracture, stress-BME und stress fracture. Group 3 reactive BME: inflammatory gonarthritis, degenerative gonarthrosis, postoperative and tumours. The typical MRI morphologies and differential diagnosis of these BME manifestations will be described. The different therapeutic consequences will also be briefly mentioned.

[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.

[MRI after meniscus and cruciate ligament surgery]. / MRT nach Meniskus- und Kreuzbandoperationen.

Nowadays, due to its high diagnostic accuracy, MR imaging is the method of choice for the evaluation of knee joint disorders pre- and postoperatively. Accurate diagnosis is sometimes possible only if the reporting radiologist has knowledge of the therapeutic procedures and the surgical report. Frequently, further therapeutic management is strongly influenced by MR examinations and radiological reports.

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.

[Acute osseous traumatic lesions of the shoulder girdle]. / Das akute ossäre Trauma des Schultergürtels.

Traumatic injuries to the shoulder girdle are common lesions and occur from birth on through the whole life. Depending on the patient's age, localization and type of injury change. Diagnosis of acute osseous traumatic lesions to the shoulder is based on evaluation of trauma mechanism, patient's examination and, as for the most cases, conventional radiographs. Only in certain cases additional radiological examinations are necessary. As a minimum, two to three images in different planes, anteriorposterior, lateral and axillary, are recommended in order to display all components of the shoulder girdle without superposition. Knowledge of common clinical classifications systems is necessary for exact diagnosis in order to permit decision on conservative or operative treatment of injury.

[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.

[Middle field and low field magnetic resonance tomography in wrist injuries]. / Mittelfeld- und Niederfeld-Magnetresonanztomographie bei Handgelenkverletzungen.

PURPOSE: To evaluate the diagnostic value of magnet resonance imaging in comparison of a dedicated 0.2-T unit and a 1.0-T unit in patients with clinically suspected scaphoid fractures and other wrist fractures. MATERIAL AND METHODS: In 20 patients (14 m/6 f) with clinically suspected scaphoid fractures and a normal six view radiographic exam, magnet resonance imaging was performed first with the dedicated 1.0-T unit and afterwards with the 0.2-T unit within 7 days after trauma. T1 weighted spin-echo, STIR and T2-weighted 3D GRE sequences were performed. RESULTS: The 0.2 Tesla dedicated system is inferior to the 1.0 Tesla unit concerning the outcome of the 3 examiners. Especially the areas of bone bruise showed different results: each examiner detected at least two more cases of bone bruise with the 1.0 Telsa unit, which could not be defined with the 0.2 Tesla unit. CONCLUSIONS: This study shows, how utmost sensitive magnet resonance imaging is referring to unremoved fractures of the scaphoid and to other wrist abnormalities. Results with the 0.2 Tesla dedicated system was inferior compared to the 1.0 Tesla unit.

[Kinematic magnetic resonance tomography in functional disorders of joints and vertebral articulations]. / Kinematische Magnetresonanztomographie bei Funktionsstörungen von Gelenken und Wirbelverbindungen.

Imaging studies of peripheral joints and of vertebral junctions are of major importance in the diagnosis of many degenerative diseases of the musculoskeletal system. Radiograms with flexion and extension views are regarded as standard for diagnosing abnormalities of the spine, the patello-femoral joint, and other articulations. With magnetic resonance imaging (MRI), kinematic studies can be performed analogously. With high gradient field strengths and in-phase and opposed-phase gradient echo sequences it is possible to study the motion of joints continuously. First results show that this technique may be added to static magnetic resonance imaging sequences in certain cases with hypermobility or instability of the knee and other major joints.

[Diagnostic imaging of giant cell tumors]. / Riesenzelltumoren in der Bildgebung.

Although classified as benign neoplasms, giant cell tumors are locally aggressive with a high recurrence rate of 30-50%. The histological appearance include osteoclast-like, multinucleated giant cells and round to spindle-shaped mono-nuclear stromal cells. These neoplasms predominately affect adults in the third and forth decades of life (70-80%). Giant cell tumors predominately arise in long tubular bones (75-95%) with the majority occurring around the knee (50%). The next most common site being the distal radius (10%). The epicenter of giant cell tumors is in the epiphysis. The radiographic signs of giant cell tumors are a geographical radiolucency with no internal mineralization, a thinning of the cortex, eccentric in the epiphysis of long bones. MRI signs of giant cell tumors are high signal intensity in T2-weighted images, high contrast media enhancement, fluid levels, signs according to haemorrhage and haemosiderin deposition. CT shows the expanded and thinned cortex. Plain radiographs remain the mainstay of diagnosis of giant cell tumors. MRI and CT are important for staging and therefore for surgical planning.

Magnetic resonance imaging and histology of repair in femoral head osteonecrosis.

Different repair processes affect the clinical course of nontraumatic avascular femoral head osteonecrosis, not just necrotic lesion size and location. Fourteen femoral heads were retrieved at total hip arthroplasty after core decompression treatment, or after conservative treatment was done on 13 male patients diagnosed with different stages of femoral head osteonecrosis. To determine repair types, features of coronal magnetic resonance images were correlated with light microscopy findings on corresponding coronal undecalcified sections and microradiographs of the retrieved femoral heads. In five femoral heads, repair of necrotic bone and marrow remained restricted to the reactive interface for as many as 63 months, producing the diagnostic osteosclerotic rim with adjacent hypervascularity (limited repair). Nine femoral heads showed extension of the repair process into the necrosis. In five femoral heads, predominant resorption of necrotic bone led to femoral head breakdown within 2 to 50 months (destructive repair). In four femoral heads, reparative bone formation had started from subchondral fractures and/or the reactive interface, definitely reducing the size of the necrotic area (reconstructive repair). In the latter, the disease progressed slowly or stopped for as many as 45 months, irrespective of treatments, but elimination of risk factors seemed beneficial. Although core decompression did not always reach the necrotic area and improve repair, it reduced accompanying bone marrow edema and could delay the disease progress. Osteonecrosis with limited repair can be identified on magnetic resonance images obtained at followup, but the similar signal changes of destructive and reconstructive repair cannot be distinguished on magnetic resonance images alone. The evidence of reconstructive repair in nontraumatic osteonecrosis, however, gives hope for treatments that can improve repair to a sufficient creeping substitution of the affected femoral head.

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.

[Diagnostic imaging in femur head necrosis]. / Bildgebung bei der Hüftkopfnekrose.

Diagnosis of avascular necrosis (AVN) of the hip has been improved by the technical progress of imaging modalities during the last decade. For a long period, only plain radiographs had been available. Scintigraphy and computed tomography contributed to differential diagnosis and early detection of bone necrosis. In the meantime, MR imaging has gained special value in the evaluation of AVN. It is now the method of choice for early detection as well as for assessment in later stage disorders. Using the ARCO system, all imaging modalities and their diagnostic viability are described. Findings regarding the different stages of AVN are correlated to tissue-specific changes.

[Pathomorphological aspects and repair mechanisms of femur head necrosis]. / Pathomorphologische Aspekte und Reparaturmechanismen der Femurkopfosteonekrose.

The pathomorphologies of non-traumatic femoral head osteonecroses (ON) are usually similar, despite various known pathogenetic factors. The size and position of the subchondral bone and marrow segment, becoming necrotic after the ischemic event(s), and the kind of repair processes determine the time course and thus the fate of this hip joint disease. Four cases of conservatively or core decompression-treated femoral head ON were selected to demonstrate differently effective repair mechanisms which are discussed in respect to existing therapeutic concepts. Diagnostic criteria from magnetic resonance imaging follow-ups were correlated with light microscopy findings on undecalcified ground and microtome sections from femoral heads retrieved at total joint replacement. Initial stage (ARCO 0) and reversible early stage ON (ARCO 1) after incomplete ischemias can apparently show spontaneous sufficient repair. After extensive and complete ischemia, however, ON progresses without detectable changes on plain radiographs into irreversible early stage ON (ARCO stage 2). Only in exceptional cases (with small, medially located necroses), a spontaneous sufficient repair seems possible. Usually, early ARCO stage 2 ON with intact articular surface shows no remodeling of the subchondral necrotic bone and fatty marrow, but only ineffective repair with fibrovascular tissue invasion and bone resorption at the vital bone border. Repeated bone appositions on partly resorbed necrotic trabeculae form the sclerotic rim in this pathognomonic reactive interface. New bone formation can also be increased underneath the necrotic area and reactive interface when surrounded by accompanying bone marrow edema. Core decompression in ARCO stage 2 ON, even if it reaches the necrotic lesion, can at best delay progression of the disease, but never leads to complete reconstruction of the necrotic area. More likely, after both conservative and operative treatment, destructive resorption without effective consecutive bone formation will lead sooner or later to collapse of the articular surface and thus to mechanical instability of transition stage ON (ARCO stage 3). On the other hand, this subchondral fracture can apparently also cause reconstructive repair which, by involving chondral and membranous ossification in this "creeping substitution", can reduce the necrotic area. However, it cannot prevent progression into late stage ON (ARCO stage 4) with secondary joint destructions. Principally, besides the rare sufficient repair in initial and certain early ON, three forms of insufficient repair in the necrotic area can be distinguished: lack of remodeling, destructive remodeling, and reconstructive remodeling. To date, no therapeutical intervention exists which leads to complete healing of irreversible ON stages by reconstructive repair. Improved understanding of pathomorphology and repair mechanisms, however, could be the basis for future therapeutical concepts which should aim at the complete regeneration of the osteonecrotic area.