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Rationale and Objectives Publishing is critical for academic medicine career advancement. Rejection of manuscripts can be demoralizing. Obstacles faced by clinical faculty may include lack of time, confidence, and optimal writing practices. This study describes the development and evaluation of a peer-writing group, informed by theory and research on faculty development and writing. Materials and Methods Five clinical-track radiology faculty members formed a “Writers' Circle” to promote scholarly productivity and reflection on writing practices. Members decided to work with previously rejected manuscripts. After members' initial meeting, interactions were informal, face to face during clinical work, and online. After the first 6 months, an anonymous survey asked members about the status of articles and evaluations of the writing group. Results Ten previously rejected articles, at least one from each member, were submitted to the Circle. In 6 months, four manuscripts were accepted for publication, five were in active revision, and one was withdrawn. All participants (100%) characterized the program as worth their time, increasing their motivation to write, their opportunities to support scholarly productivity of colleagues, and their confidence in generating scholarship. Conclusions Peer-support writing groups can facilitate the pooling of expertise and the exchange of recommended writing practices. Our peer-support group increased scholarly productivity and provided a collegial approach to academic writing.

Aims: The purpose of this study was to evaluate the ability of ultrasound in detecting subscapularis tendon pathology with operative correlation. Methodology: A retrospective study was conducted on 86 patients who had shoulder ultrasound prior to surgical repair from January 2006 to August 2008. All sonographic examinations and surgical reports were reviewed. Sonographic evaluation of subscapularis tendon, including normal, tendinosis, partial thickness tear, full thickness tear, and complete tear were correlated to operative reports. Results: Of the 86 patients, 19 patients had surgically proven abnormal subscapularis tendons. There was 100% ultrasound concordance in tendinosis (n = 1), 100 % ultrasound concordance in partial thickness tears (n =3), 88 % ultrasound concordance in full thickness tears (n = 8), 57 % ultrasound concordance in complete tears (n = 7). Overall, there was 79% ultrasound concordance

MR imaging appearances of different types of reconstructive muscle flaps following reconstructive surgery of the lower extremity with associated post-surgical changes due to altered anatomy, radiation, and potential complications, can be challenging. A multidisciplinary therapeutic approach to tumors allows for limb salvage therapy in a majority of the patients. Decision-making for specific types of soft tissue reconstruction is based on the body region affected, as well as the size and complexity of the defect. Hematomas and infections are early complications that can jeopardize flap viability. The local recurrence of a tumor within six months after a complete resection with confirmed tumor-free margins and adjuvant radiation therapy is rare. Identification of a new lesion similar to the initial tumor favors a finding of tumor recurrence.

Objectives The purpose of this study was to determine whether any sonographic features of jumper's knee can predict the outcome after sonographically guided percutaneous patellar tendon fenestration. Methods Patients were identified between July 2001 and March 2009 who had clinical and sonographic findings of jumper's knee, who had failed conservative treatment, and who had sonographically guided percutaneous fenestration of the patellar tendon. Pain levels were assessed before and 4 weeks after fenestration. Sonograms were retrospectively characterized with regard to echogenicity, size, definition, location, calcification, and hyperemia of the abnormal patellar tendon region. Sonographic findings before fenestration were correlated with clinical outcomes. Results A total of 45 patellar tendons (32 consecutive patients) were included in the study. The average prefenestration functional pain score was 3.6 (range, 2-5), and the average postprocedure functional pain score after 4 weeks was 1.4 (range, 0-5). The preprocedure sonographic finding that correlated with an improved clinical outcome after tendon fenestration was the presence of a well-defined tendon abnormality. No other sonographic findings were associated with the clinical outcome. After fenestration, 76% (34 of 45) showed clinical improvement; 24% (11 of 45) showed no change; and 0% (0 of 45) had worse symptoms at 4 weeks. Conclusions The presence of a well-defined area of tendinosis on sonography was associated with clinical improvement after percutaneous sonographically guided fenestration of the patellar tendon. All tendons either improved (76%) or showed no change (24%) in the functional pain score at 4 weeks after fenestration.

Objectives Implanted mesh for inguinal hernia repair is often difficult to visualize with gray scale sonography and may present without the knowledge of the sonographer. We sought to evaluate the utility of the twinkling artifact produced by inguinal mesh to assist in mesh identification. Methods Two reviewers evaluated focused sonographic examinations of 44 inguinal regions, 24 of which had implanted inguinal mesh. The sonographic examinations consisted of static gray scale and color Doppler images with both linear and curvilinear array transducers. The presence of the twinkling artifact and visibility of the mesh were graded on a 4-point visibility scale. Results Inguinal mesh was not easily identified on gray scale imaging using either the curvilinear array (P = .5) or linear array (P = .5) transducer. The mesh was definitely seen in 3 of 24 inguinal regions using the linear array transducer and 2 of 24 inguinal regions using the curvilinear array transducer. In 79% of inguinal regions with mesh, the twinkling artifact was produced with the curvilinear array transducer only. The artifact was not elicited when using the linear array transducer. With the use of the curvilinear array transducer and the presence of the twinkling artifact, there was a significant chance of correctly identifying the presence of mesh (P Conclusions Standard gray scale imaging alone is not reliable when identifying inguinal mesh. The twinkling artifact was present in 79% of inguinal regions with mesh when evaluated with a low-frequency curvilinear array transducer.

The aim of this study was to evaluate the magnetic resonance imaging (MRI) interpretation proficiency of musculoskeletal fellows in training.Between July 2003 and June 2007, 14 musculoskeletal fellows were independently tested with 20 MRI studies of the knee and shoulder at four separate time points during their fellowship years. Trends in true-positive and false-positive interpretation results were evaluated. Fellows who completed their residencies at the fellowship institution (internal fellows) were compared with those from other residencies (external fellows).There was a significant improvement in proficiency between the initial and final (9-month) evaluations (P.0001). At the initial evaluation, there was a mean of 52.8% (41.7 of 79) true-positive results (range, 32-51); at 9 months, there was a mean of 71.0% (56.1 of 79; range, 40-72). The number of false-positive results also declined during this time period from a mean of 8.1 (range, 2-13) at initial evaluation to 4.7 (range, 2-8) at 9 months (P.001). External fellows had more incorrect diagnoses initially but showed greater improvement than internal fellows at 9 months.Fellows continued to improve their MRI interpretation skills throughout the first 9 months of their fellowships. External fellows were slightly less proficient at the start of their fellowships but slightly more proficient at 9 months compared to internal fellows.

Objective The purposes of this study were (1) to review the sonographic in vitro and in vivo appearances of mesh for surgical repair of abdominal wall hernias, (2) to describe sonographic techniques and discuss the limitations of sonography in evaluation of mesh hernia repair, and (3) to illustrate common complications after mesh repair shown with sonography. Methods We identified interesting cases from the musculoskeletal sonographic database as well as from the teaching files of the authors, with surgical or other cross-sectional imaging corroboration. Results A compilation of the sonographic appearances of mesh used for anterior abdominal wall and inguinal hernia repair and complications diagnosable by sonography is presented. Conclusions Sonography can be effective for evaluation of mesh and complications after mesh repair of anterior abdominal wall and inguinal hernias.

Summary Objective To elucidate the role of body mass index (BMI) and knee osteoarthritis (OAK) by evaluating measures of body composition including fat mass and skeletal muscle mass (SMM). Methods Data are from 541 women enrolled in the Michigan Bone Health Study, a longitudinal, population-based study. At visits in 1998 and 2002, radiographs were taken of both knees and were evaluated for the presence of OAK (≥2 on the Kellgren–Lawrence (K–L) scale). Joint space width (JSW) was measured with electronic calipers. Fat mass and SMM were determined using bioelectrical impedance analysis. Results In 2002, the prevalence of OAK was 11% in this population of women whose mean age was 47 years. Fat mass, lean mass, SMM, waist circumference and BMI were greater in women with OAK compared to those without OAK. In multiple variable analyses adjusted for age, fat mass and SMM explained OAK prevalence and increasing OAK severity better than models with BMI; further SMM explained more variation than did fat mass. SMM was positively associated with level of left and right medial JSW while there was no consistent association of JSW and BMI or fat mass. Conclusion Fat mass and SMM were associated with K–L OAK score and the amount of joint space, with more variation explained by SMM. SMM was highly associated with JSW. Therefore, though obesity, frequently characterized by BMI, is a frequently reported risk factor for OAK, this mis-attribution may mean that interventions that focus on weight loss as treatment for osteoarthritis should be aware that this may negatively impact muscle mass.

OBJECTIVES The purpose of this article is to evaluate the diagnostic accuracy of sonography in clinically occult femoral hernias and to describe our sonographic technique. METHODS The clinical and imaging data for 93 outpatients referred by general surgeons, all of whom underwent sonographic evaluation and surgery, were reviewed retrospectively. Of these, 55 patients who underwent surgical exploration for groin hernias within 3 months of sonography and met all inclusion criteria were included in the study. The sonographic technique involves using the pubic tubercle as an osseous landmark to identify and appropriately visualize the femoral canal. The Valsalva maneuver is then used to differentiate the movement of normal fat (a potential pitfall) from true herniation in the femoral canal. Surgical findings were used as the reference standard by which sonographic results were judged. Two-by-two contingency tables were used to calculate the sensitivity, specificity, positive predictive value, and negative predictive value. RESULTS In these 55 patients, surgery revealed 15 femoral hernias. Eight femoral hernias occurred in women, and 7 occurred in men. For diagnosing femoral hernias, sonography demonstrated sensitivity of 80%, specificity of 88%, a positive predictive value of 71%, and a negative predictive value of 92%. True-positive cases of femoral hernias have a sonographic appearance of a hypoechoic sac with speckled internal echoes. When examining during the Valsalva maneuver, a femoral hernia passes deep to the inguinal ligament, expands the femoral canal, displacing the normal canal fat, and effaces the femoral vein. CONCLUSIONS Sonography can exclude femoral hernias with high confidence in light of its exceptional negative predictive value. With attention to technique and imaging criteria, the diagnostic accuracy of sonography can be enhanced.

Photoacoustic tomography (PAT), a nonionizing, noninvasive, laser-based technology was adapted to joint imaging for the first time. Pulsed laser light in the near-infrared region was directed toward a joint with resultant ultrasonic signals recorded and used to reconstruct images that present the optical properties in subsurface joint tissues. The feasibility of this joint imaging system was validated on a Sprague Dawley rat tail model and verified through comparison with histology. With sufficient penetration depth, PAT realized tomographic imaging of a joint as a whole organ noninvasively. Based on the optical contrast, various intra- and extra-articular tissues, including skin, fat, muscle, blood vessels, synovium and bone, were presented successfully in images with satisfactory spatial resolution that was primarily limited by the bandwidth of detected photoacoustic signals rather than optical diffusion as occurs in traditional optical imaging. PAT, with its intrinsic advantages, may provide a unique opportunity to enable the early diagnosis of inflammatory joint disorders, e.g., rheumatoid arthritis, and to monitor therapeutic outcomes with high sensitivity and accuracy.

Rationale and objectives One mission of an academic radiology department is to teach. The greatest teaching effort is directed at radiology residents. As clinical work demands increase, informal, non−revenue-generating, teaching may suffer. We sought to determine the economic consequences of teaching. Materials and methods With the use of a picture archiving and communications system, 6 radiology faculty members independently interpreted and dictated digitally acquired bone and chest radiographs for 1 hour alone and again 10−12 weeks later with a first-year resident. During the second session, the quality of teaching was graded by independent observers. The number of cases, relative value units (RVUs), and reimbursement for each session were calculated. Results The difference in number of cases dictated working alone (mean, 44.7) and with a first-year resident (mean, 23.5) was significant ( P = 0.007). The difference between RVUs generated by faculty alone (mean, 9.0) and with a resident (mean, 4.5) also was significant ( P = 0.006), and the difference in dollars billed when working alone (mean, $1558.45) and with a resident (mean, $777.65) was significant ( P = 0.007). As teaching quality increased, the number of cases interpreted, dollars billed, and RVUs trended lower. Conclusion Informal resident teaching significantly reduces clinical throughput, reducing examination volume, RVUs, and dollars billed by approximately half.

To understand a linear artifact that projects deep to reflective structures that move rapidly while using tissue harmonic imaging with pulse inversion (PI) sonography. We hypothesize that this artifact is due to a cancellation error between firings in PI imaging, and it is, therefore, similar in generation to the twinkling artifact in color Doppler sonography. This artifact could be studied with the use of surfaces of different roughness to represent different rates of motion, in which roughness corresponds to spatial fluctuations in surface height. Given very slight variations in beam focusing as occurs with sonographic imaging arrays, these spatial fluctuations translate into temporal fluctuations in the received signal as would occur with tissue motion.We scanned 4 different sandpaper grits and a smooth surface through a water path using fundamental and PI mode, 1- and 2-pulse techniques, respectively. The sandpaper and the smooth surface were scanned through a water path at mechanical indices of 0.1 to 0.7. Four independent images were subtracted pairwise to remove nonfluctuating signals. These noise pixels were counted and analyzed.Analysis of variance showed that the noise generated behind the different surfaces was highly significantly different. Two-tailed t tests generally showed significant differences in the quantity of noise between fundamental and harmonic imaging behind the roughest 3 grades of sandpaper. A multiple regression model showed significantly greater slopes for harmonic imaging for all grades of sandpaper and the smooth surface.The noise and, by extension, the linear streak artifact in musculoskeletal imaging are dependent on the mechanical index and are functions of sandpaper roughness. This would be equivalent to a subtraction error between 2 firings due to soft tissue motion, and the artifact may be a way to identify rapid soft tissue motion in PI images.

Six patients were retrospectively identified as having undergone lateral ligament reconstruction surgery. The surgical procedures were categorized into four groups: direct lateral ligament repair, peroneus brevis tendon rerouting, peroneus brevis tendon loop, and peroneus brevis tendon split and rerouting. At radiography and magnetic resonance (MR) imaging, the presence of one or more suture anchors in the region of the anterior talofibular ligament indicates direct ligament repair, whereas a fibular tunnel indicates peroneus brevis tendon rerouting or loop. Both ultrasonography (US) and MR imaging demonstrate rerouted tendons as part of lateral ankle reconstruction; however, MR imaging can also depict the rerouted tendon within an osseous tunnel if present, especially if T1-weighted sequences are used. Artifact from suture material may obscure the tendon at MR imaging but not at US. With both modalities, the integrity of the rerouted peroneus brevis tendon is best evaluated by following the tendon proximally from its distal attachment site, which typically remains unchanged. The rerouted tendon or portion of the tendon can then be traced proximally to its reattachment site. Familiarity with the surgical procedures most commonly used for lateral ankle ligament reconstruction, and with the imaging features of these procedures, is essential for avoiding diagnostic pitfalls and ensuring accurate assessment of the ligament reconstruction.

Obese individuals have slowed conduction in the median nerve across the wrist, but the mechanism for this is not established. This case-control study of 27 obese subjects and 16 thin subjects was designed to test the hypothesis that obese individuals have higher carpal canal pressures and more median nerve swelling than thin individuals. All subjects were asymptomatic for hand symptoms, and had measurements of median and ulnar sensory nerve conduction in the nondominant hand, ultrasound measurement of the median nerve cross-sectional area proximal to the carpal canal, and carpal canal pressure measurement. There was no difference in age or gender ratio between the obese and thin groups. The median nerve cross-sectional area was equal in the obese and thin groups (9.3 mm2 vs. 9.4 mm2), as was the carpal canal pressure (16.2 mmHg vs. 15.5 mmHg, respectively). There was a strong correlation between median nerve conduction slowing across the wrist and median nerve cross-sectional area at the wrist (r = 0.55, P = 0.002). Obesity does not influence carpal canal pressure or the size of the median nerve at the wrist. However, there is a strong association between slowed median nerve conduction and increased nerve size which suggests endoneurial edema as a metabolic mechanism; the conduction slowing does not appear to be related to mechanical stress. Muscle Nerve 30: 481–485 2004

Objective With the use of surgical findings as the reference standard, the purpose of this study was to describe the sonographic findings of partial-thickness and complete tears of the quadriceps tendon and to determine whether sonography can potentially aid diagnosis. Methods Three hundred eighty-nine consecutive sonographic reports (January 1996 to April 2001) of the knee/quadriceps tendon were reviewed retrospectively and assessed for subsequent surgery on the quadriceps tendon. Seven cases were thus identified. Findings at surgery (complete versus partial tears) were compared with the original sonography reports. Results All 4 partial tears and 1 of 2 complete tears were diagnosed correctly on the basis of sonography. One complete tear was described as a partial tear on the basis of sonography. In a seventh case, complete disruption of the extensor mechanism with osseous avulsion of the superior pole of the patella was identified correctly. Dynamic scanning was essential in diagnosing a partial quadriceps tendon tear in 1 case. Conclusions Sonography, including the use of dynamic evaluation, was helpful in the diagnosis of partial-thickness tears of the quadriceps tendon and may aid in differentiation of such cases from complete quadriceps tendon tears, particularly in the acute setting. The presence of scar tissue in the setting of chronic injury may represent a potential pit-fall in the assessment of partial versus complete quadriceps tears. Further study is needed to define the accuracy of sonography for detecting quadriceps tendon tears.

We present a case of traumatic bamboo foreign body penetration through the posterior thigh extending cephalad into the pelvis sustained during skiing. The unsuspected bamboo foreign body was missed prospectively on the initial portable trauma radiograph of the pelvis, but was retrospectively quite apparent as a linear 12 x 2-cm radiolucent region overlying the left pelvis and hip region. On CT examination, the bamboo stick appeared as a round cylindrical air-filled structure of high density compared to soft tissue - the typical appearance of bamboo. Bamboo foreign bodies can be recognized radiographically by this typical appearance, since it is one of the few wood products that causes high attenuation relative to soft tissue on CT.

Osteoarthritis (OA) has been characterized as a slowly evolving degenerative disease affecting cartilage and bone, with a multifactorial etiology that may differ depending on the joint site. Because OA has been considered a disease of the elderly, few population-based studies have examined its frequency and characteristics in persons under the age of 45. Objective In this cross-sectional study, we examined X-rays of both knees and the dominant hand in a population of younger black and white pre- and perimenopausal women in southeastern Michigan ( N =1053) for evidence of osteoarthritis, and reported these outcomes according to the risk factors of age, body size, injury, and smoking behavior. Design Sixteen joints of the dominant hand as well as both knee joints (weight bearing) were evaluated using the Kellgren and Lawrence Atlas of Standard Radiographs of Arthritis. Results By age 40, radiographically-defined osteoarthritis emerges in both the hands and knees. These age characteristics are observed in both black and white women, however prevalence of knee OA was higher in black females (23.1%) compared with white females (8.5%), and although prevalence of hand OA was more comparable between black (25.5%) and white females (19.2%), the joint sites affected differed. The major risk factors reported in studies of older populations are present in this younger population where OA is newly emerging. Conclusions This study provides strong evidence that primary prevention of OA must be implemented in young adulthood to curtail the emergence of radiographically-defined OA at the mid-life.

Ventilation/perfusion scans with single-photon emission tomography (SPET) were reviewed to determine their usefulness in the evaluation of lung volume reduction surgery (LVRS) candidates, and as a predictor of outcome after surgery. Fifty consecutive planar ventilation (99mTc-DTPA aerosol) and perfusion (99mTc-MAA) scans with perfusion SPET of patients evaluated for LVRS were retrospectively reviewed. Technical quality and the severity and extent of radiotracer defects in the upper and lower halves of the lungs were scored from visual inspection of planar scans and SPET data separately. An emphysema index (EI) (extent x severity) for the upper and lower halves of the lung, and an EI ratio for upper to lower lung were calculated for both planar and SPET scans. The ratios were compared with post-LVRS outcomes, 3, 6 and 12 months after surgery. All perfusion and SPET images were technically adequate. Forty-six percent of ventilation scans were not technically adequate due to central airway tracer deposition. Severity, extent, EI scores and EI ratios between perfusion and SPET were in good agreement (r = 0.52-0.68). The mean perfusion EI ratio was significantly different between the 30 patients undergoing biapical LVRS and the 17 patients excluded from LVRS (3.3+/-1.8 versus 1.2+/-0.7; P0.0001), in keeping with the anatomic distribution of emphysema by which patients were selected for surgery by computed tomography (CT). The perfusion EI ratio correlated moderately with the change in FEV1 at 3 months (r = 0.37, P = 0.04), 6 months (r = 0.36, P = 0.05), and 12 months (r = 0.42, P = 0.03), and the transition dyspnea index at 6 months (r = 0.48, P = 0.014) after LVRS. It is concluded that patients selected to undergo LVRS have more severe and extensive apical perfusion deficits than patients not selected for LVRS, based on CT determination. SPET after aerosol V/Q imaging does not add significantly to planar perfusion scans. Aerosol DTPA ventilation scans are not consistently useful. Perfusion lung scanning may be useful in selecting patients with successful outcomes after LVRS.

Objective To determine whether Caucasian women ages 28–48 years with newly defined osteoarthritis (OA) would have greater bone mineral density (BMD) and less bone turnover over time than would women without OA. Methods Data were derived from the longitudinal Michigan Bone Health Study. Period prevalence and 3-year incidence of OA were based on radiographs of the dominant hand and both knees, scored with the Kellgren/Lawrence (K/L) scale. OA scores were related to BMD, which was measured by dual-energy x-ray absorptiometry, and to serum osteocalcin levels, which were measured by radioimmunoassay. Results The period prevalence of OA (K/L grade ≥2 in the knees or the dominant hand) was 15.3% (92 of 601), with 8.7% for the knees and 6.7% for the hand. The 3-year incidence of knee OA was 1.9% (9 of 482) and of hand OA was 3.3% (16 of 482). Women with incident knee OA had greater average BMD (z-scores 0.3–0.8 higher for the 3 BMD sites) than women without knee OA (P 60%; P = 0.02) or knee OA (20%; P not significant). The average change in absolute serum osteocalcin levels was not as great in women with incident hand OA or knee OA as in women without OA (P < 0.02 and P < 0.05, respectively). Conclusion Women with radiographically defined knee OA have greater BMD than do women without knee OA and are less likely to lose that higher level of BMD. There was less bone turnover among women with hand OA and/or knee OA. These findings suggest that bone-forming cells might show a differential response in OA of the hand and knee, and may suggest a different pathogenesis of hand OA and knee OA.

An arterioarticular fistula is an unusual complication of knee arthrocentesis. We describe the sonographic findings immediately following a failed clinical attempt at knee arthrocentesis that resulted in an arterioarticular fistula. Spectral Doppler analysis confirmed the jet of blood into the hemarthrosis. Knowledge of anatomy and application of standard technique is necessary to minimize the complications of arthrocentesis.

We undertook this study to determine the CT findings of lipomatous hypertrophy of the interatrial septum, an asymptomatic and underrecognized benign proliferation of fat within the atrial septum.We retrospectively identified 12 cases of lipomatous hypertrophy of the interatrial septum by searching the radiology records at our institution from 1991 to 1995. We reviewed the CT scans of these patients to determine the distribution and morphology of fat within the interatrial septum.In all patients with lipomatous hypertrophy, a mass of fat attenuation extended from the coronary sinus to just above the level of the aortic root with relative sparing of the fossa ovalis, which resulted in a dumbbell configuration. Average dimensions were 7 cm for craniocaudal extent (range, 6-9 cm), 4.5 cm along the interatrial septum (range, 3.6-6.2 cm), and 2.7 cm perpendicular to the septum (range, 1.5-4.8 cm). Increased epicardial fat was seen on CT scans in 10 patients (83%). CT revealed mediastinal lipomatosis in six patients (50%). No patients had undergone corticosteroid treatment or total parenteral nutrition. No electrocardiographic or functional cardiac abnormalities were seen.On standard, high-resolution, and enhanced CT images, lipomatous hypertrophy of the interatrial septum is shown as a nonenhancing smoothly marginated homogeneous dumbbell-shaped mass of fat attenuation confined to the interatrial septum. These characteristic morphologic features allow confident diagnosis and help differentiate this benign condition from other cardiac masses.

Gout is an ancient disease. Last decade has brought about significant advancement in imaging technology and real scientific growth in the understanding of the pathophysiology of gout, leading to the availability of multiple effective noninvasive diagnostic imaging options for gout and treatment options fighting inflammation and controlling urate levels. Despite this, gout is still being sub-optimally treated, often by nonspecialists. Increased awareness of optimal treatment options and an increasing role of ultrasound and dual energy computed tomography (DECT) in the diagnosis and management of gout are expected to transform the management of gout and limit its morbidity. DECT gives an accurate assessment of the distribution of the deposited monosodium urate (MSU) crystals in gout and quantifies them. The presence of a combination of the ultrasound findings of an effusion, tophus, erosion and the double contour sign in conjunction with clinical presentation may be able to obviate the need for intervention and joint aspiration in a certain case population for the diagnosis of gout. The purpose of this paper is to review imaging appearances of gout and its clinical applications.

The osseous pelvis is a well-recognized site of origin of numerous primary and secondary musculoskeletal tumors. The radiologic evaluation of a pelvic lesion often begins with the plain film and proceeds to computed tomography (CT), or magnetic resonance imaging (MRI) and possibly biopsy. Each of these modalities, with inherent advantages and disadvantages, has a role in the workup of pelvic osseous masses. Clinical history and imaging characteristics can significantly narrow the broad differential diagnosis for osseous pelvic lesions. The purpose of this review is to familiarize the radiologist with the presentation and appearance of some of the common benign neoplasms of the osseous pelvis and share our experience and approach in diagnosing these lesions.

Objective. In our clinical practice, we have noted a caliber change of the posterior interosseous nerve (PIN) at the elbow as seen in the long axis on sonography simulating nerve entrapment. The objective of this study was to characterize the PIN using sonography in asymptomatic individuals. Methods. Our study retrospectively characterized the PIN in 50 elbows of 47 asymptomatic patients with sonography. Measurements of the PIN in a short-axis cross section using the circumferential trace technique and the anteroposterior (AP) dimension in the long axis were made proximal, at, and distal to the arcade of Frohse. Results. There was reduction of the AP dimension of the PIN distal to the arcade of Frohse when compared with the measurements at the arcade of Frohse and proximal to the arcade (P < .0001); however, there was no significant difference between the cross-sectional area of the PIN at all 3 levels (P = .59). Condusions. The PIN normally flattens as it enters into the supinator muscle without a notable chanqe in the cross-sectional area. This appearance should not be misinterpreted as nerve entrapment when imaged in the long axis.

We report a sonographic technique of skin marking of the projection of nonpalpable subcutaneous foreign bodies and masses using a paperclip. Localization and marking of the overlying skin assists in preoperative planning and further management.

Objective The purpose of this presentation is to review pathologic conditions that lead to pain at the radial aspect of the distal radius and to address anatomic variations of the first extensor compartment that exist and may have diagnostic and therapeutic implications. Methods Our presentation is based on a review of cases from teaching files and observations made in anatomic specimens. Results The discussed conditions include de Quervain tenosynovitis, intersection syndrome, and Wartenberg syndrome. Sonographic diagnosis of these conditions is addressed, and correlations are provided with anatomic specimens. Conclusions Sonography is able to depict and differentiate between these conditions.

To determine if levels of endogenous estrogen or estrogen metabolites are associated with an increased risk of developing knee osteoarthritis (OA) in women.Serum estradiol (E2) and 2 urinary estrogen metabolites (2-hydroxyestrone and 16alpha-hydroxyestrone) with radiographically defined prevalent and incident knee OA in 842 white and African American women from the Southeast Michigan Arthritis Cohort.The mean age and body mass index (BMI) of women in the cohort were 42.3 years and 28.5 kg/m2, respectively. Women who developed radiographically defined knee OA had significantly greater odds of having baseline endogenous early follicular phase estradiol concentrations in the lowest tertile (47 pg/ml; odds ratio [OR] 1.88, 95% confidence interval [95% CI] 1.07-3.51) compared with those with estradiol concentrations in the middle tertile [47-77 pg/ml]), after adjustment for age, BMI, and other covariates. Women who developed knee OA also had greater odds of having baseline urinary concentrations of 2-hydroxyestrone in the lowest tertile (OR 2.9, 95% CI 1.49-5.68) compared with women with 2-hydroxyestrone concentrations in the middle tertile), after adjustment for covariates. Women who developed knee OA were more likely to have a ratio of 16alpha-hydroxyestrone to 2-hydroxyestrone in the highest tertile (0.86; OR 1.86, 95% CI 1.01-3.44 compared with women with ratios in the 0.54-0.86 range), after adjustment for other covariates.There were significant associations of lower baseline serum estradiol and urinary 2-hydroxyestrone with developing knee OA in middle-aged women.

Although extensive research is ongoing in the realm of ultrasound contrast media used to visualize arterial blood flow, a cadaveric model to test such media has not been evaluated. This study shows that arterial flow can be visualized via ultrasound in a cadaveric model during embalming. Five of eight cadaveric subjects showed flow reliably in axillary, brachial, and radial arteries, while two of these showed flow into the distal segments of the digital arteries. Thus, a cadaveric model for the assessment of ultrasound contrast media is proposed. Additionally, it was noted that no statistically significant relation between cadaveric gender, age, weight to height ratio, or time elapsed between death and embalming versus extent of arterial flow visualized was observed. Thus, such a cadaveric model population may be male or female and have variable age, weight, height, and time elapsed between death and embalming without affecting the consistency of arterial flow.

The rotator cuff muscles generate torque forces to move the humerus while acting in concord to produce balanced compressive forces to stabilize the glenohumeral joint. Thus, rotator cuff tears are often associated with loss of shoulder strength and stability, which are crucial for optimal shoulder function. The dimensions and extent of rotator cuff tears, the condition of the involved tendon, tear morphologic features, involvement of the subscapularis and infraspinatus tendons or of contiguous structures (eg, rotator interval, long head of the biceps brachii tendon, specific cuff tendons), and evidence of muscle atrophy may all have implications for rotator cuff treatment and prognosis. Magnetic resonance imaging can demonstrate the extent and configuration of rotator cuff abnormalities, suggest mechanical imbalance within the cuff, and document abnormalities of the cuff muscles and adjacent structures. A thorough understanding of the anatomy and function of the rotator cuff and of the consequences of rotator cuff disorders is essential for optimal treatment planning and prognostic accuracy. Identifying the disorder, understanding the potential clinical consequences, and reporting all relevant findings at rotator cuff imaging are also essential.

The purpose of this research was to describe the sonographic findings of pectoralis major injuries with clinical, surgical, and magnetic resonance imaging (MRI) correlation.Images from sonographic examinations of the pectoralis major muscle of 6 patients were retrospectively evaluated and characterized. The sonographic findings were compared with clinical, surgical, and MRI findings.The 6 patients were male (mean age, 30 years) with injuries sustained during weight lifting, football, and shotgun firing. Two of the 6 patients had MRI correlation; 1 had surgical correlation; 2 had both surgical and MRI correlation; and 1 had clinical follow-up. The sternal head was injured in 5 patients; 4 involved the musculotendinous junction, and 1 involved the distal tendon. The sonographic findings of muscle fiber retraction and surrounding hemorrhage allowed identification of the affected muscle. Direct impact injury causing hematoma involved the clavicular head in 1 patient. In total, 5 cases were partial-thickness pectoralis major tears, whereas complete distal tendon disruption was found in 1.Sonographic imaging longitudinal to the pectoralis muscle fibers showed fiber disruption, retraction, and possible hypoechoic or anechoic hematoma, most commonly involving the musculotendinous junction of the sternal head. Distal tendon assessment is important to evaluate for a full-thickness pectoralis major tear.

Sports-related and overuse conditions may cause painful abnormalities that include muscle and tendon tears, tendon avulsion, bone remodeling, and stress fracture. Adductor insertion avulsion syndrome (AIAS), or thigh splints, is a stress-related avulsive injury of the adductor muscles that occurs at the posteromedial midfemoral diaphysis (Fig. 1). 1,2 Repetitive avulsive stresses in AIRS may result in a spectrum of findings, which include traction periostitis, osseous stress reaction, and stress fracture. 1 1 Bone scan findings in AIAS include linear uptake along the medial shaft of the femur. 3-5 The findings associated with AIAS on magnetic resonance (MR) imaging have been described recently 1,2 They include bone marrow edema, adjacent enhancing periostitis, and stress fracture of the posteromedial femoral diaphysis. 1,2 Musculoskeletal sonography is commonly used to evaluate muscle and tendon injury. 6 To our knowledge, the sonographic findings of AIAS have not been described. We present the sonographic findings in a patient with clinical and MR imaging evidence of AIAS.

One method for performing effective shoulder arthrography with a fluoroscopically guided anterior approach is described. The technique can ensure success while injury to the cartilaginous labrum is avoided, which is essential when arthrography is performed in conjunction with magnetic resonance (MR) imaging. The key features of the technique include supine positioning of the patient with the shoulder in external rotation, marking the skin just lateral to the humeral head cortex, inserting the needle perpendicular to the fluoroscopy beam, testing the injection with an anesthetic agent, and confirming intraarticular needle placement with iodinated contrast material. The procedure can be followed by an injection of dilute gadolinium solution for subsequent MR imaging. Proper patient and needle positioning as well as accurate confirmation of intraarticular needle placement are critical to a successful and atraumatic shoulder arthrographic examination. © RSNA, 2003

Received March 23, 2001, from the Department of Radiology, University of Michigan Hospitals, Ann Arbor, Michigan. Revision requested April 30, 2001. Revised manuscript accepted for publication June 4, 2001. Address correspondence and reprint requests to David A. Jamadar, MB, BS, Radiology, TC 2910, University of Michigan Hospitals, 1500 E Medical Center Dr, Ann Arbor, MI 48109-0326. onography is now used to evaluate many disorders of the musculoskeletal system.1 One such example is evaluation of the median nerve in carpal tunnel syndrome.2 Sonographic findings such as median nerve enlargement immediately proximal to the carpal tunnel and bowing of the flexor retinaculum have been described in these patients.2 A correct diagnosis relies on accurate identification of the median nerve and an understanding of the osseous landmarks delineating the carpal tunnel. The presence of multiple closely approximated linear echogenic structures at the volar wrist makes identification of the median nerve difficult; differentiation from the palmaris longus tendon and other tendons may occasionally prove challenging. We present a technique that allows reliable identification of the median nerve at several locations in the distal forearm and wrist by using the real-time capability of sonography. Median nerve pathologic characteristics are also described.

Complex knee injuries are common, often resulting from multiple forces: varus, valgus, hyperextension, hyperflexion, internal rotation, external rotation, anterior or posterior translation, and axial load. Certain combinations of forces are known to cause specific injury patterns. After a review of the literature, the authors developed a mechanism-based classification system based on patterns of bone marrow edema and ligament injury for complex knee injuries depicted at magnetic resonance imaging. The classification system takes into account knee position and forces and recognition of patterns of bone injury and complementary soft-tissue injury. Ten mechanism-based injury patterns were recognized: (a) pure hyperextension, (b) hyperextension with varus, (c) hyperextension with valgus, (d) pure valgus, (e) pure varus, (f) flexion with valgus and external rotation, (g) flexion with varus and internal rotation, (h) flexion with posterior tibial translation, (i) patellar dislocation (flexion, valgus, and internal rotation of femur on fixed tibia), and (j) direct trauma. Recognition of these patterns may help assess the full extent of knee injury, particularly at the posterolateral and posteromedial corners of the knee.

Objective : To assess whether the presence of subchondral bone marrow abnormalities (bone marrow edema (BME)) and cartilage defects, determined by magnetic resonance imaging (MRI), would explain the difference between painful osteoarthritis of the knee (OAK) compared with painless OAK or pain without OAK. Method : Four groups of women (30 per group), aged 35–55 years, were recruited from the southeast Michigan Osteoarthritis cohort (group 1: painful OAK; group 2: painless OAK; group 3: knee pain without OAK; and group 4: no OAK or knee pain). OAK was defined by a Kellgren–Lawrence score of 2 or greater, while pain was based on self-report. BME and cartilage defects were identified from MRI. Results : BME lesions were identified in 56% of all knees. BME lesions were four times (95% CI=1.7, 8.7) more likely to occur in the painless OAK group as compared with the group with pain, but no OAK. BME lesions >1cm were more frequent (OR=5.0; 95% CI=1.4, 10.5) in the painful OAK group than all other groups. While the frequency of BME lesions was similar in the painless OAK and painful OAK groups, there were more lesions, >1cm, in the painful OAK group.About 75% of all knees had evidence of some cartilage defect, of which 35% were full-thickness defects. Full-thickness cartilage defects occurred frequently in painful OAK. One-third of knees with full-thickness defects and 47% of knees with cartilage defects involving bone had BME >1cm. Women with radiographic OA, full-thickness articular cartilage defects, and adjacent subchondral cortical bone defects were significantly more likely to have painful OAK than other groups (OR=3.2; 95% CI=1.3, 7.6). Conclusion : The finding on MRI of subchondral BME cannot satisfactorily explain the presence or absence of knee pain. However, women with BME and full-thickness articular cartilage defects accompanied by adjacent subchondral cortical bone defects were significantly more likely to have painful OAK than painless OAK.

Objective We assessed the probability that mid-aged women with a Kellgren and Lawrence (K–L) score of 1 are likely to progress to a score of 2 or regress to a score of zero at a second time point, 2–3 years later.Methods Osteoarthritis (OA) of measurements (weight-bearing X-rays and interviews) were undertaken in women from the Southeast Michigan population who were ≥40 years of age, and who participated in both the 1995 and 1998 measurements (N=679).Results Of the 17.1 % of women with a 1995 K–L score of 1 in their right knee, 37.1% had a K–L score of 1 in 1998 while 32.8 % had a score of ≥2 and 30.2% had a score of zero. For 26.0% of women, the score progressed by at least one unit over the 2.5 year period whereas scores for only 7.0% of women regressed in the same time period. Women who had a K–L score of 1 in the right knee in 1995 were 2.5 times more likely to have a K–L score of 1 in 1998 (95% CI=1.6–3.8); and were 2.2 times more likely to have a K–L score of 2 or greater (95% CI=1.4–3.5) in 1998 compared with other scores. These women were 74% less likely to have a score of zero in 1998 (95% CI=0.2–0.4). Further, other risk factors, specifically age and BMI were predictors of increasing K–L grade in 1998.Conclusion These findings suggest that a score of 1 is part of the advancement to emergent OAK; and suggest the following criteria to characterize individuals who are at an intervenable stage on the pathway toward OAK: age ≥40, BMI ≥30, and K–L score of ≥1. From the perspective of both the individual and the examiner, these assessment characteristics are relatively simple to assess clinically. Copyright 2002 OsteoArthritis Research Society Intenational. Published by Elsevier Science Ltd. All rights reserved.

Discrepancies exist between radiographic osteoarthritis of the knee (OAK) and report of knee joint pain. Little is known about how these two definitions of osteoarthritis (OA) and their correlates differ between African American (AA) and Caucasian (CA) women.Objective We compared the prevalence of radiographic OAK and knee joint pain in AA and CA women, and the congruency of these outcomes according to age, body size, and knee injury.Design A cross-sectional study of African American and Caucasian women aged 40–53 years (N=829) in Southeast Michigan used the Kellgren and Lawrence Atlas of Standard Radiographs of Arthritis to characterize radiographs of both knee joints (weight bearing) and self-report of knee pain.Results Current pain was a significantly more sensitive predictor of radiographic OAK among AA women (Se=0.51) compared to CA women (Se=0.35). Specificity was similar between AA women (Sp=0.77) and CA women (Sp=0.82). Positive predictive value was significantly greater for AA compared with CA women (PV+=0.40 and PV+=0.15, respectively). The odds of having radiographic OAK increased with BMI >32kg/m2in both groups. Knee pain was related to BMI in CA women, but not AA women. Previous knee injury was associated with knee pain in both AA and CA women (OR=3.0 and OR=2.4).Conclusions Joint pain in AA women was more likely to be associated with radiographic OAK as compared with CA women. This suggests differences in these two groups in both how pain is experienced in the OAK process and in the prevalence of non-OAK related pain in knee joints.

Objective We evaluated C-reactive protein (C-RP), a quantitative marker of the acute phase response, as a potential biomarker of prevalent and incident osteoarthritis of the knee (OAK). Methods Serum C-reactive protein concentrations were characterized with ultrasensitive rate nephelometry in a population-based sample of 1025 women (318 African-American and 707 Caucasian) who are enrollees in a study of musculoskeletal conditions at the mid-life. Assignment of OAK was based on Kellgren-Lawrence (K–L) scores of 2 or more on radiographs. Prevalent OAK was based on the baseline (1996) score while the classification of incident OAK was based on a score of 2 or greater at the follow-up examination 2.5 years later amongst those with a baseline K–L scores of 0 or 1. Results At baseline, the prevalence of radiographic OAK was 12% in participants who were aged 27–53 years and 18% in the subgroup of women aged 40–53 years. The mean C-RP value was 2.31mg/L, with values ranging from below detection (0.3mg/L) to 47.4mg/L. Higher C-RP concentrations were associated with both prevalent and incident OAK ( P 0.0001, and P 0.0001, respectively). For each K–L score increase from 0 to 3, there was a significantly higher mean C-RP value. Compared to women without incident OAK, women who developed OAK in the 2.5-year follow-up had significantly higher baseline C-RP concentrations. Women with bilateral OAK had higher C-RP concentrations than women with unilateral OAK (6.65mg/L±0.56 vs 3.63mg/L±0.42, P 0.007). BMI was highly correlated with C-RP ( r =0.58) and obesity was an effect modifier with respect to OAK and C-RP concentrations. When stratified according presence or absence of OAK and obesity (BMI >30kg/m 2 ), mean C-RP values were: obesity and OAK, 6.3±0.4mg/L; obesity but not OAK, 4.3mg/L±0.2; no obesity but OAK, 1.7mg/L±0.8; and neither obesity nor OAK, 1.3mg/L±0.2mg/L. These stratum means were significantly different from each other, indicating a higher C-RP with OAK after accounting for obesity. Conclusion C-RP, as a measure of an acute phase response and inflammation, is highly associated with OAK; however, its high correlation with obesity limits its utility as an exclusive marker for OAK. Copyright 2002 OsteoArthritis Research Society International. Published by Elsevier Science Ltd. All rights reserved .