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Standard radiography of the cervical spine is still the first imaging procedure applied in degenerative disease of the cervical spine. Spondylosis deformans, osteochondrosis and uncovertebral arthrosis are well depicted by such images. Whether or not additional imaging is needed depends on the clinical symptoms. Special projections (anteroposterior oblique radiographs, lateral radiographs in flexion and extension) may be the next step. For many abnormalities, mainly of the intervertebral discs and the myelon, MR imaging has become the standard procedure, largely because of its multiplanar capabilities and its excellent contrast resolution. CT can be used instead of MR imaging if the latter method is not available, and its strength lies in the depiction of bone abnormalities. Scintigraphy is suitable for early detection of abnormalities with unclear clinical symptoms and may then indicate the correct level of the cervical spine for MR imaging or CT. Myelograms and myelo-CT can no longer be considered routine imaging methods. A number of imaging abnormalities are not strictly related to clinical findings and should therefore always be discussed in the clinical context.

The longitudinal relaxation time T(1) of native cartilage is frequently assumed to be constant. To redress this, the spatial variation of T(1) in unenhanced healthy human knee cartilage in different compartments and cartilage layers was investigated. Knees of 25 volunteers were examined on a 1.5 T MRI system. A three-dimensional gradient-echo sequence with a variable flip angle, in combination with parallel imaging, was used for rapid T(1) mapping of the whole knee. Regions of interest (ROIs) were defined in five different cartilage segments (medial and lateral femoral cartilage, medial and lateral tibial cartilage and patellar cartilage). Pooled histograms and averaged profiles across the cartilage thickness were generated. The mean values were compared for global variance using the Kruskal-Wallis test and pairwise using the Mann-Whitney U-test. Mean T(1) decreased from 900-1100 ms in superficial cartilage to 400-500 ms in deep cartilage. The averaged T(1) value of the medial femoral cartilage was 702+/-68 ms, of the lateral femoral cartilage 630+/-75 ms, of the medial tibial cartilage 700+/-87 ms, of the lateral tibial cartilage 594+/-74 ms and of the patellar cartilage 666+/-78 ms. There were significant differences between the medial and lateral compartment (p

We evaluated the diagnostic value of magnetic resonance imaging retrospectively in 72 patients (76 examinations). 10 examinations were normal, 2 showed normal variants, 21 inflammatory disease, 2 osteoarthritis, 7 neoplasia, 21 traumatic changes, 3 pathology in systemic disease, 5 avascular necrosis, 5 iatrogenic changes. When considering the original reports, accuracy had been 72.4%, sensitivity 75%, specificity 62.5%. After review of the hard copies several diagnoses were revised, improving the values to 86.6%, 84.4% and 100% respectively. Compared with other radiologic examinations the main advantages of magnetic resonance imaging were its high contrast resolution and the free choice of the imaging plane. The main disadvantages were the reduced spatial resolution compared to CT and the significantly worse definition of calcification and cortical bone. In conjunction with other radiologic and clinical examinations magnetic resonance imaging played an important role in the examination of avascular necrosis, inflammation, tendon pathology and neoplasia.

MR Imaging is proving to an effective means for evaluating the shoulder. The use of a surface coil and high resolution scanning techniques have allowed detailed analysis of normal anatomy and suspected pathology of the shoulder. On the other way arthroscopic inspection provides a more extensive visualization of the joint in different positions. 31 patients, well documented, were studied with MR Imaging and correlated with findings in arthroscopy and open revision in some cases. The MR studies were retrospective interpreted without the knowledge of the results of other diagnostic procedures. For the evaluation of rotator cuff tears MRI proved to have a sensitivity of 83.3% and an accuracy of 90.3%. When Arthroscopy was correlated with open revision the sensitivity was 61.8% and the accuracy 78%. Labral pathology and Hill-Sachs lesions will be better evaluated in arthroscopy as in MRI (sensitivity of arthroscopy 100% and of MRI 69%, accuracy of arthroscopy 100% and of MRI 87.1%). With the high resolution scanning technique and a surface coil MRI has been shown to be useful in the evaluation of rotator cuff tears and impingement syndrome but not in diagnosis of labral pathology and Hill-Sachs lesions.

Impingement by prominence at the femoral head-neck junction on the anterior acetabular rim may cause early osteoarthritis. Our aim was to develop a simple method to describe concavity at this junction, and then to test it by its ability to distinguish quantitatively a group of patients with clinical evidence of impingement from asymptomatic individuals who had normal hips on examination. MR scans of 39 patients with groin pain, decreased internal rotation and a positive impingement test were compared with those of 35 asymptomatic control subjects. The waist of the femoral head-neck junction was identified on tilted axial MR scans passing through the centre of the head. The anterior margin of the waist of the femoral neck was defined and measured by an angle (α). In addition, the width of the femoral head-neck junction was measured at two sites. Repeated measurements showed good reproducibility among four observers. The angle α averaged 74.0° for the patients and 42.0° for the control group (p < 0.001). Significant differences were also found between the patient and control groups for the scaled width of the femoral neck at both sites. Using standardised MRI, the symptomatic hips of patients who have impingement have significantly less concavity at the femoral head-neck junction than do normal hips. This test may be of value in patients with loss of internal rotation for which a cause is not found.

The purpose of this study was to assess the diagnostic role of MR arthrography in patients with tendinopathy or rupture of the long biceps tendon.MR arthrograms of 42 consecutive patients with arthroscopic or surgical confirmation of diagnosis (16 normal biceps tendons, 19 with tendinopathy, and seven with ruptures) were analyzed independently by two radiologists. Visibility of the biceps tendon, caliber changes, contour irregularities, and signal intensities were assessed separately in the parasagittal and axial planes. In addition, the two radiologists made an overall evaluation of abnormalities of the biceps tendon using both MR imaging planes.The most reliable MR findings for tendinopathy were caliber changes (sensitivity was 59% for observer 1 and 82% for observer 2; specificity was 88% and 64%, respectively) and signal abnormalities (sensitivity, 77% and 88%, respectively; specificity, 75% and 43%, respectively) in the parasagittal plane. Absence of visualization of the tendon in the parasagittal plane was a reliable sign for rupture (sensitivity, 86% and 86%, respectively; specificity, 94% and 87%, respectively). The overall sensitivity for detecting abnormalities (tendinopathy or rupture) was 92% for observer 1 and 89% for observer 2. Specificity was 56% and 81%, respectively.MR findings of tendinopathy and rupture of the biceps tendon are subtle. However, the combination of several MR criteria in two imaging planes makes a reasonably accurate diagnosis possible. The biceps tendon should not only be assessed in the bicipital sulcus on axial images but also on parasagittal images.

OBJECTIVE: The objective of our study was to assess the ability of a 0.5-T superconducting, open-configuration MR system to guide laser diskectomies. The study was performed ex vivo on six human cadavers as well as in vivo on three patients. CONCLUSION: The macroscopic size of necrosis correlated well with the monitored temperature spread (r2 = .76-.85). After MR-guided introduction of the laser fiber into the targeted disk space, temperature spread was visualized in all subjects.

Purpose Our goal was to determine the normal MR arthrographic appearance of the elbow and to identify the potential diagnostic pitfalls of this technique. Method MRI with intra-articularly administered gadopentetate dimeglumine was performed in seven elbow joints derived from cadavers. Coronal, sagittal, and axial SE T1-weighted images with fat suppression and coronal 3D SPGR images with fat suppression were obtained in each elbow. The elbows were then sectioned. Results This technique allowed depiction of the cartilaginous surfaces of the elbow joint as well as clear delineation of the inner surface of the collateral ligaments. Potential diagnostic pitfalls included fat pads projecting into the joint, synovial folds, and cartilaginous pseudoerosions. Conclusion MR arthrography allows clear delineation of the intraarticular structures of the elbow. However, diagnostic pitfalls exist that increase the difficulty of interpreting MR arthrographic images.

The purpose of this investigation was to compare gadopentetate and saline as contrast media in MR arthrograms of the glenohumeral joint. In 60 consecutive patients MR arthrograms with either gadopentetate (n = 26) or saline (n = 34) were performed. After injection of gadopentate, 3D gradient-echo (GE) images were obtained (TR 32 ms, TE 10 ms, flip angle 40 degrees). With saline, double-echo steady-state images (heavily T2-weighted 3D GE images) were obtained (TR 40 ms, TE 9/45 ms, flip angle 40 degrees). In the last 14 of these patients T2-weighted turbo spin-echo (SE) images were added (TR 2900 ms, TE 96 ms). Contrast-to-noise ratios standardized for imaging times proved to be superior for the gadolinium arthrograms compared with GE and SE saline arthrograms (intra-articular fluid vs subacromial fat: p = 0.0001 and 0.0008; intra-articular fluid vs supraspinatus tendon: p = 0.0001 and 0.046). Using a qualitative scoring system gadolinium arthrograms were superior to saline arthrograms (p0.0001 and p0.0001). Saline arthrograms in combination with GE and SE sequences are inferior to gadopentetate arthrograms with GE sequences.

This article reviews the pathogenesis and clinical and imaging findings in shoulder impingement syndrome. Shoulder impingement is caused by compression of the supraspinatus tendon underneath the coracoacromial arch, mainly in forward flexion of the arm. Different stages of impingement syndrome are described. Stage I relates to edema and hemorrhage of the supraspinatus tendon. Stage II is characterized by bursal inflammation and fibrosis, as well as tendinopathy. In stage III there is a tear of the rotator cuff. Clinical signs may overlap. Moreover, calcifying tendinitis, fractures and pain originating from the cervical spine may mimic shoulder impingement syndrome. Imaging is important for the exact diagnosis. Standard radiographs are the basis of imaging in shoulder impingement syndrome. They may demonstrate subchondral sclerosis of the major tuberosity, subacromial spurs, and form anomalies of the acromion. They are also important in the differential diagnosis of shoulder impingement syndrome and demonstrate calcifying tendinitis, fractures and neoplasm. Ultrasonography has found acceptance as a screening tool and even as a final diagnostic method by many authors. However, there is a high interobserver variability in the demonstration of rotator cuff tears. Its usefulness has therefore been questioned. MR imaging is probably the method of choice in the evaluation of the rotator cuff and surrounding structures. Several investigations have demonstrated that differentiation of early findings, such as tendinopathy versus partial tears, may be difficult with MR imaging. However, reproducibility for fullthickness tears appears to be higher than for sonography. Moreover, specificity appears to be superior to sonography. MR arthrography is not universally accepted. However, it allows for more exact differentiation of discrete findings and may be indicated in preoperative planning. Standard arthrography and CT have a limited role in the current assessment of the rotator cuff.

We reviewed 30 patients operated on because of acute (n = 14) or chronic (n = 16) rupture of the posterior cruciate ligament (PCL) with an average follow-up time of 6.9 years. The clinical outcome was expressed using the OAK and the International Knee Documentation Committee (IKDC) evaluation forms. All patients had undergone posterior stress X-radiography, 14 patients had additionally undergone magnetic resonance imaging (MRI). OAK score showed good or excellent results in 93% of the acute and 38% of the chronic cases. The IKDC form, however, revealed nearly normal results in only 29% of the acute and 6% of the chronic cases. The length and thickness of the operated PCL on MRI correlated with the clinical result.

We describe two sibs with geroderma osteodysplasticum (GO) who, in addition to the known clinical and radiologic manifestations of the disorder, presented a metaphyseal peg indenting the epiphysis of the long bones, particularly at the knees. The peg was visible only at the age of 4 to 5 years but was invisible in infancy and following physeal closure. This may explain why this anomaly was not described in previous reports of 23 patients in 11 families with GO. The metaphyseal peg is an abnormality of bone development so far unknown to us. We speculate that it represents a primary, age-dependent alteration of bone shape and hence a new genetic bone marker apparently specific to GO. © 1996 Wiley-Liss, Inc.

Radical and nonradical ‘reactive oxygen species (ROS)’ are normally occurring intermediates of aerobic cellular metabolism. Under physiologic conditions, they are kept from causing noticeable damage by antioxidant enzymes and small molecular weight compounds. Oxidative stress develops when antioxidants are overwhelmed by ROS. This may occur via overproduction of the latter and/or by deficiency of antioxidant defense. ROS in excess, especially the highly reactive hydroxyl radical (HO·), which is usually generated with the catalytic help of transition metals such as ferrous ions, can attack virtually all biological structures. Consequences may be functionally relevant when sensitive macromolecules are altered by ROS, in particular DNA (e.g. mutations, base modifications), proteins (formation of disulfide bridges etc.), lipids (lipid peroxidation), and polysaccharides (depolymerisation). Type and severity of the damage and cellular responses to it, including adaptive enzyme induction, determine the outcome in terms of cellular dysfunction or death. Many human disorders are thought to be associated with oxidative stress. ROS seem to play a predominant role, for instance, in radiation effects, damage by oxidant chemicals (many poisons and chemotherapeutic drugs), lung lesions due to hyperbaric oxygen, and chronic deficiencies of selenium and vitamin E. Oxidative stress is also thought to be important in other diseases and processes, e.g. in ischemia-reperfusion damage, central nervous system injury and stroke, severe chronic inflammatory disorders (for example rheumatoid arthritis), the development of arterial atherosclerosis, cancero-genesis, and ageing.

The goal of this investigation was to describe the MR appearance of traumatic fraying or detachment of the superior portion of the glenoid labrum including the insertion of the tendon of the long head of the biceps. This condition is caused either by an acute injury or by repeated overhead motion during participation in sports. In nine patients with such a lesion, the arthroscopic report and MR images were available for review. These patients were 22-64 years old (mean, 38). In four patients only fraying was noted during arthroscopy, in four patients the superior part of the labrum was detached together with the insertion of the biceps tendon, and in one case there was a bucket-handle tear of the superior portion of the labrum. The MR images were retrospectively evaluated by three osteoradiologists in conference. Signal changes within the labrum and detachment of the labrum were noted, and the findings were compared with the results of arthroscopy. MR imaging did not allow recognition of simple fraying. In two of the five cases with arthroscopic findings of detachment of the superior labrum from the glenoid rim, differentiation between complete and partial labral detachments was not possible even with MR arthrography. However, in these cases the patient's age and history led to the correct diagnosis. We conclude that early traumatic abnormalities of the superior portion of the labrum cannot be detected with MR imaging. Complete detachment, however, can be demonstrated if the patient's age and history are taken into consideration.

In 11 children (aged 4 weeks to 8 months) with congenital dysplasia of the hip and complete dislocations of the femoral head, magnetic resonance imaging was performed after closed reduction. Gradient echo sequences allowing for a short examination time are well suited for imaging of the articular cartilage and documentation of the position of the femoral head. The use of magnetic resonance imaging decreases the risk that incompletely reduced or redislocated hips after closed or open reduction are retained in this position. Magnetic resonance imaging can be recommended for postreduction assessment of congenital dislocation of the hip in infants and may significantly reduce the need for arthrography.

We prospectively evaluated the diagnostic value of sonography and magnetic resonance imaging (MRI) in 24 shoulders in 23 patients with suspected rotator cuff tears using arthrography as gold standard. Sonography demonstrated 14 of 15, MRI 10 of 15 rotator cuff tears, respectively. Sonography diagnosed seven of nine intact rotator cuffs correctly, MRI eight of nine. In a retrospective study we reviewed the diagnostic value of sonography and MRI in other pathologies of the shoulder including intra-articular pathology, humeral head and acromioclavicular joint pathology, and calcification. We conclude that with regard to cost and patient compliance, sonography should be the first radiologic examination in suspected rotator cuff tears if performed by an experienced sonographer. MRI is superior in depicting additional pathology and is less operator dependent. It may thus become the method of choice for the evaluation of the rotator cuff and related pathology in the future.

Diseases of the heart, chest & breast : , Diseases of the heart, chest & breast : , کتابخانه دیجیتالی دانشگاه علوم پزشکی و خدمات درمانی شهید بهشتی

In some cases neither the clinical pattern nor the findings of magnetic resonance imaging (MRI) can help to determine the cause of a cervical myelopathy. The differential diagnosis of such cases as a rule includes spondylotic myelopathy, a solitary focus of multiple sclerosis and an intramedullary tumour in early stage. Worsening of signs and symptoms due to the circumscribed lesion of the spinal cord can require surgical treatment, even if no certain diagnosis could be stated thus far. The question is how to choose a surgical procedure which is beneficial for all three kinds of spinal cord pathology in their initial stage, which at the same time does not jeopardise spine and spinal cord and allows secondary surgery if needed after the precise nature of the lesion has been assessed. Ventral decompression and fusion with or without dorsal decompression seems to be a convincing procedure.

Osteoporosis plays an increasing medical, social, and economic role in our society. Vertebral body fractures are the most common fractures, along with fractures around the hip joint, and fractures of the distal radius due to osteoporosis. An osteoporotic vertebral compression fracture can lead to incapacitating back pain and immobility and often requires in-hospital treatment. Vertebroplasty is an effective procedure consisting of the percutaneous injection of polymethylmethacrylate (PMMA) cement into vertebral bodies. Preliminary studies showed promising clinical results with this new technique. As there is a high incidence of cement leakage during the injection of the cement, we prefer to perform the procedure under computed tomography control with a fluoro-CT-option. Furthermore, we recommend that the procedure is only done in collaboration with a spine surgeon. In case of a neurological complication, immediate decompression of the spinal canal is mandatory. Vertebroplasty is a very promising, effective and safe method for the treatment for osteoporotic vertebral compression fractures. Based on our preliminary results, this method can be recommended for a more widespread clinical use.

The authors compared the effects of patient-controlled interscalene analgesia (PCIA) with ropivacaine 0.2% and patient-controlled intravenous analgesia (PCIVA) with opioids on hemidiaphragmatic excursion and respiratory function after major shoulder surgery.Thirty-five patients scheduled for elective major shoulder surgery were prospectively randomized to receive either PCIA or PCIVA. All patients received an interscalene block before surgery. In the PCIA group, a catheter was introduced between the anterior and middle scalene muscles. Six hours after the initial block, patients received for 48 h either a continuous infusion of 0.2% ropivacaine through the interscalene catheter at a rate of 5 ml/h plus a bolus dose of 3 or 4 ml with a lockout time of 20 min (PCIA group) or a continuous intravenous infusion of nicomorphine at a rate or 0.5 mg/h plus a bolus dose of 2 or 3 mg with a lockout time of 20 min (PCIVA group). Hemidiaphragmatic excursion and respiratory function were assessed with the patient in a 45 degrees semirecumbent position the day before the operation and 20 min (in the operating room), 24 h, and 48 h after the initial block by means of ultrasonography and spirometry, respectively. Pain relief was regularly assessed, side effects were noted, and patient satisfaction was rated 6 h after the end of the study.Hemidiaphragmatic excursion was similar in the two groups 20 min after interscalene block. Hemidiaphragmatic excursion was increased in the PCIA group on the nonoperated side 24 and 48 h after the interscalene block (P0.05). Pulmonary function was similar in the two groups at each time. Pain was better controlled in the PCIA group at 12 and 24 h (P0.05). The incidence of nausea and vomiting were 5.5% versus 60% for the PCIA and PCIVA groups, respectively (P0.05). Patient satisfaction was greater in the PCIA group (P0.05).The use of PCIA or PCIVA techniques to provide analgesia after major shoulder surgery is associated with similar effects on respiratory function. In the PCIA group, hemidiaphragmatic excursion showed a significantly greater amplitude 24 and 48 h after the initial block on the nonoperated side. The PCIA technique provided better pain control, a lower incidence of side effects, and a higher degree of patient satisfaction.

We present a case of a 13 year old girl with swelling and pain of the right lower leg persisting for four months. The radiological and histological diagnosis is osteofibrous dysplasia. Osteofibrous dysplasia is a rare bone lesion predominantly affecting the cortex of the tibia. Almost all patients are younger than ten years at presentation. Swelling is a typical clinical manifestation. Radiologically and even histologically the distinction between the osteofibrous dysplasia and the more aggressive adamantinoma can be difficult. Other bone lesions potentially mimicking osteofibrous dysplasia include: fibrous dysplasia, osteoid osteoma, osteosarcoma, osteoblastoma and intracortical Brodie's abcess. The natural course of the disease is unpredictable. Lesions with typical radiological appearance are considered to be "no touch lesions". In equivocal cases block resection (with both a diagnostic and therapeutic purpose) should be performed.

Purpose: To evaluate the effect of MR arthrography of the shoulder on diagnostic thinking and therapeutic decisions by orthopedic shoulder surgeons. Material and Methods: Orthopedic surgeons completed a questionnaire before and after MR arthrography for 73 consecutive patients. the main indications were suspected rotator cuff abnormalities. the clinical diagnosis, the degree of confidence in this diagnosis, and the therapeutic decision were noted before and after MR imaging. Surgical reports were available for 34 patients. Results: Thirty-four percent of the pre-MR imaging diagnoses were withdrawn after MR imaging, and new diagnoses were made after MR imaging in 13% of the case & Confidence in the diagnosis increased significantly after MR imaging for supraspinatus and infraspinatus lesions ( p < 0.05). Changes of therapeutic decision after MR imaging were noted in 36 of the 73 patients (49%). In 23 patients, more invasive therapeutic procedures were initiated after MR imaging, and a more conservative treatment was implemented for 13 patients. Agreement of MR diagnoses with surgery was 94% for supraspinatus tears, 87% for infraspinatus tears, 77% for subscapularis tears, and 81% for biceps tendon lesions. Agreement of clinical diagnoses with surgery was 56%, 83%, 50%, and 64%, respectively. Conclusion: MR arthrography of the shoulder has a major effect on diagnostic thinking and therapeutic decisions by orthopedic shoulder surgeons.

The purpose of this study was to determine whether occult bony injuries or other characteristic MR abnormalities are frequent in patients suspected of having traumatic tears of the rotator cuff.MR arthrography of the shoulder was performed in 24 consecutive patients with suspected traumatic tears of the rotator cuff. MR findings were analyzed with regard to abnormalities of the supraspinatus, infraspinatus, and subscapularis tendons; and the humeral head. A comparison group of 24 consecutive patients with symptoms of nontraumatic tears of the rotator cuff was included in the investigation.Radiographically occult fractures of the greater tuberosity were found in nine (38%) of 24 patients with clinically suspected traumatic tears of the rotator cuff (seven of which occurred in patients40 years old). Nine partial-thickness and five full-thickness supraspinatus tears were found in the trauma group. In the comparison group, the corresponding numbers were 13 and 10, respectively. Seven partial lesions of the cranial border of the subscapularis and six complete subscapularis tears (all six in patients40 years old) were found in the trauma group (nine and one in the comparison group).Occult greater tuberosity fractures and complete subscapularis tears are commonly seen on MR images in patients suspected of having traumatic tears of the rotator cuff. Greater tuberosity fractures should be looked for specifically in patients younger than 40 years, and subscapularis tears should be looked for specifically in patients older than 40 years.

The purpose of this project was to employ quality management methods in order to decrease throughput times for orthopedic outpatients sent to the department of radiology. The following intervals were measured at the onset of the study and after 6 and 12 months: (a) between arrivals at outpatient clinic and radiology counter; (b) between arrival at radiology counter and time of last radiograph; and (c) between time of last radiograph and radiology report printing time. After the initial measurement, numerous changes were initiated both in radiology and in orthopedic surgery. The mean interval between arrival at the outpatient clinic and in radiology decreased by one third from 60 min during the first measurement to 40 (p < 0.001) and 41 min during the second and third measurement. The proportion of patients with total radiology times of more than 30 min decreased from 41 to 29 % between the first and third measurements (p < 0.001). The corresponding results for radiology times of more than 45 min were 17 and 11 % (p = 0.03). A standard type of quality management program can be employed successfully in order to reduce radiology throughput times for orthopedic outpatients.

The purpose of this study was to perform percutaneous laser disc decompression (PLDD) under MR guidance in an open configuration 0. 5-T MR system. Following failed conservative treatment for 6 months, eight patients with contained disc herniations were enrolled in the study. Following MR guided introduction of the laser fiber into the targeted disc space, the laser-induced temperature distribution was visualized using a color-coded subtraction technique based on a T1-weighted GRE sequence. In seven patients PLDD could be performed. In all cases laser effects were depicted by MR. In this regard the color-coded technique was found to be superior to conventional magnitude images. Whereas no apparent decrease in the extent of herniation was discovered immediately following PLDD, T2-weighted FSE images showed signal intensity alterations in two of the seven patients. Clinical evaluation, obtained 3-4 months after PLDD, revealed a fair (n = 2) or good (n = 4) response to the treatment. One patient showed no change in symptoms. MR guidance and monitoring of PLDD is feasible within an open 0.5-T system and seems to render PLDD more safe and controllable.

A number of abnormalities of the shoulder joint can cause pain or dysfunction. Imaging of this complex joint is demanding. Standard radiographs are considered to represent the basis of all imaging. For more detailed diagnoses, especially concerning soft tissue, more advanced imaging methods are required. Standard arthrography (without combination with either CT or MRI) is rarely indicated anymore. Bone scintigraphy is another imaging method with limited use in shoulder joint abnormalities (neoplasm, infection, occult fracture). Sonography is useful in abnormalities of the rotator cuff and the biceps tendon. This method is commonly employed for screening. CT is useful in the demonstration of complex fractures. CT arthrography is indicated in instability of the glenohumeral joint and is competing with MR arthrography. MRI and MR arthrography are the imaging method of choice for many indications, mainly due to their free choice of imaging planes and excellent contrast resolution. These methods provide the most detailed diagnosis mainly with regard to abnormalities of the rotator cuff (partial versus intact or full-thickness tears) and the biceps tendon and are useful in the assessment of instability.

The purpose of this evaluation was the description of potentially misleading MR appearances of osteoid osteoma. The MR images of 10 patients with osteoid osteoma were retrospectively evaluated and compared to radiographic, intraoperative and histologic findings. 4 of the 10 abnormalities were located in the proximal femur, two in the lumbar spine, and one each in the tibial plateau, in the cervical spine, in the sacrum and in the first metacarpal. 8 of the 9 nidi visible on standard radiographs and/or CT scans were demonstrated on MR images. Edema was visible within the bone marrow in 3, within soft tissue in 2 and in both locations in 4 MR examinations. The soft tissue abnormalities were circumscribed in 3 patients and could be misdiagnosed as soft tissue tumors or an abscess in these patients. One of 5 osteoid osteomas located in the proximity of a joint mimicked septic arthritis. The MR appearance of osteoid osteoma may be misleading. However, false diagnoses usually can be avoided with a careful search of a nidus. MR imaging in osteoid osteoma is important for differential diagnosis.

The authors evaluated the use of MR-imaging of the menisci compared to arthroscopy considered as the gold standard by which all noninvasive imaging procedures of the knee have to be measured.In a prospective study, we evaluated the use of MRI in 50 patients with clinically suspected disorders of the meniscus, followed by an arthroscopic examination by an experienced arthroscopist. MRI studies were performed after clinical evaluation and were interpreted by an experienced radiologist, who had no knowledge of the clinical findings.The accuracy of the diagnosis from MRI was 78 per cent for the medial meniscus (sensitivity 79 per cent and specificity 78 per cent) and 94 per cent for the lateral meniscus (sensitivity 50 per cent and specificity 98 per cent). The average age of the patients was 34 years, with a range from 3 to 73 years. The imaging studies revealed 9 false positive test and suggested that the meniscus was either degenerated or form in the horizontal plane. In all 9 menisci the abnormal MR imaging signal was limited to the posterior horns. The positive predictive value was 59 per cent and the negative predictive value was 94 per cent representing a moderate level of diagnostic certainty, both in patients who had a positive result and in those who had a negative result. High predictive negative value of MRI indicates that a negative MRI is quite reliable for meniscal lesions.Problems of MR-imaging are the popliteus tendon sheath and the transverse ligament. This ligament is seen in association with a large branch of the lateral inferior geniculate artery, and may be mistaken for a grade 3 signal intensity in the anterior horn of the lateral meniscus.A normal MRI allows to eliminate a meniscal lesion and so there is no need for a diagnostic arthroscopy. But with a pathologic MRI there is a risk to establish too often the diagnostic of a meniscal lesion rather then to identify structural modifications as a degeneration.

This article reviews the pathogenesis and clinical and imaging findings in shoulder impingement syndrome. Shoulder impingement is caused by compression of the supraspinatus tendon underneath the coracoacromial arch, mainly in forward flexion of the arm. Different stages of impingement syndrome are described. Stage I relates to edema and hemorrhage of the supraspinatus tendon. Stage II is characterized by bursal inflammation and fibrosis, as well as tendinopathy. In stage III there is a tear of the rotator cuff. Clinical signs may overlap. Moreover, calcifying tendinitis, fractures and pain originating from the cervical spine may mimic shoulder impingement syndrome. Imaging is important for the exact diagnosis. Standard radiographs are the basis of imaging in shoulder impingement syndrome. They may demonstrate subchondral sclerosis of the major tuberosity, subacromial spurs, and form anomalies of the acromion. They are also important in the differential diagnosis of shoulder impingement syndrome and demonstrate calcifying tendinitis, fractures and neoplasm. Ultrasonography has found acceptance as a screening tool and even as a final diagnostic method by many authors. However, there is a high interobserver variability in the demonstration of rotator cuff tears. Its usefulness has therefore been questioned. MR imaging is probably the method of choice in the evaluation of the rotator cuff and surrounding structures. Several investigations have demonstrated that differentiation of early findings, such as tendinopathy versus partial tears, may be difficult with MR imaging. However, reproducibility for fullthickness tears appears to be higher than for sonography. Moreover, specificity appears to be superior to sonography. MR arthrography is not universally accepted. However, it allows for more exact differentiation of discrete findings and may be indicated in preoperative planning. Standard arthrography and CT have a limited role in the current assessment of the rotator cuff.

Vertebral pain is common in elderly patients. This article reviews indications and results of imaging in these patients. The differential diagnosis of degenerative disease and the mass important emergency situations are discussed. Standard radiographs are crucial for adequate diagnosis due to high spatial resolution and the excellent overview they provide. Computed tomography is useful in bone abnormalities and is an important diagnostic tool in this population. Magnetic resonance imaging is preferable in abnormalities of the cervical spine and in suspected spondylodiscitis. Myelography, CT myelography and discography are rarely indicated, but may be ordered for operative planning. Bone scintigraphy is useful in detection of multilocular lesions and can be used for assessing the activity of pathologic processes.