Case report 599

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/46798/1/256_2004_Article_BF00197627.pd

Growing bone cysts in long-term hemodialysis

All patients with chronic renal failure undergoing hemodialysis for more than 10 years in the university hospitals of Leuven were selected for this study. The medical records and radiographs of these 21 patients were studied retrospectively. Skeletal surveys were examined for the presence and location of subchondral cysts. The predialysis films and the films taken after 5, 10, 15 and 20 years of dialysis were reviewed. Subchondral cysts that grew in size and number were found in the wrist, humeral head, hip, and patella. Accurate measurements were made of cysts in the wrist and compared with a control group. In the dialysis group, cystic involvement of the wrist was more common and the size and number of the cysts were larger. Soft tissue swelling was seen in the dialysis group but not in controls. Soft tissue swelling was assessed on shoulder radiographs by measuring the acromiohumeral distance (ACD) and in the knees by ultrasonic measurement of synovial thickness [25]. In 11 patients synovial or bone biopsies or aspirated synovial fluid were available. All these patients had swollen joints and multiple subchondral periarticular cysts. Amyloid deposition was found in ten of these patients, and this proved to be composed of B2 microglobulins in seven (Table 1).Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/46797/1/256_2004_Article_BF00197929.pd

Acute patellar tendon ruptures: The diagnostic utility of sonography for tear detection and characterization in the emergent setting.

Purpose To determine the accuracy of ultrasound for diagnosing and characterizing acute patellar tendon ruptures, as well as to investigate secondary sonographic signs that may aide in identifying tear location, using surgical findings as the reference standard. Methods The sonographic findings of 46 consecutive knee ultrasounds obtained for clinically-suspected extensor mechanism injury (23 cases reporting a torn patellar tendon and 23 cases reporting an intact patellar tendon) were compared with intra-operative findings in those patients who underwent patellar tendon surgery. Twomusculoskeletal radiologists blindly and retrospectively reviewed all 46 cases to indicate the presence or absence of a patellar tendon tear, to identify suspected tear location, and to comment on refraction artifact and peritendinous fluid, which were also correlated with intraoperative findings. Results The sensitivity, specificity, positive predictive value, and negative predictive value of ultrasound for diagnosing patellar tendon rupture were 100%. Further, ultrasound correctly identified tear location in 94% of surgically-proven cases. The presence of refraction artifact (P \u3c 0.05) and increasing amount of peritendinous fluid (P \u3c 0.05) were associated with higher likelihood of tear. Relying solely on refraction artifact to identify tear location proved less accurate (P \u3c 0.05, P = 0.08) than using all sonographic signs available. There was no difference in tear location accuracy with varying amount of peritendinous fluid (P \u3e 0.24) or conspicuity of refraction artifact (P = 1.0). Conclusions Ultrasound is highly accurate for diagnosing and characterizing acute patellar tendon ruptures. Because acute repair is preferred in order to avoid long-term morbidity, and missed clinical diagnosis reportedly ranges from 10-50%, we advocate for an increasing role of ultrasound in the emergency setting to rapidly and effectively evaluate the integrity of the patellar tendon

Ultrasound evaluations and guided procedures of the painful joint arthroplasty.

The purpose of this article is to describe the use of ultrasound for the diagnosis and treatment of painful joint arthroplasty. Ultrasound plays a crucial role in the diagnosis of the painful joint arthroplasty, especially given its unique dynamic capabilities, convenience, and high resolution. Ultrasound guidance is also instrumental for procedures in both diagnosing and in select cases, treating the painful joint arthroplasty. Topics to be discussed in this article include trends in arthroplasty placement, benefits of the use of ultrasound overall, and ultrasound evaluation of periprosthetic joint infections. We will also review the sonographic findings with dissociated/displaced components and adverse reaction to metallic debris including metallosis, trunnionosis, and metal-on-metal pseudotumors. Additionally, we will discuss ultrasound evaluation of tendon pathologies with arthroplasties, including dynamic maneuvers to evaluate for tendon impingement/snapping. Finally, we will cover ultrasound-guided joint arthroplasty injection indications and precautions. KEY POINTS: • Ultrasound is preferred over MRI in patients with joint arthroplasty and plays a crucial role in diagnosis, especially given its unique dynamic capabilities, convenience and high resolution. • It is especially beneficial for US-guided aspiration in periprosthetic joint infections; effectively used to evaluate periprosthetic fluid collections, facilitating differentiation between abscesses and aseptic collections, and tracking sinus tracts. • Recently, the diagnosis of periprosthetic joint infections has shifted focus to biomarkers in the periprosthetic fluid, specifically α-defensin, which has a high sensitivity and specificity for diagnosing infection. • Cutibacterium acnes is a major pathogen responsible for shoulder arthroplasty infections, often presenting with normal laboratory values and since slow growing, must be kept for a minimum of 14 days.http://deepblue.lib.umich.edu/bitstream/2027.42/175149/2/1s00256-022-04080-y.pdfPublished versionDescription of 1s00256-022-04080-y.pdf : Accepted versio

Influence of asymptomatic rotator cuff pathology on in-vivo shoulder motion and clinical outcomes.

INTRODUCTION: Rotator cuff tears are common, affecting up to 50% (or more) of individuals over age 60 and accounting for an economic burden of $3- 5 billion per year in the U.S. alone [1,2]. Although many rotator cuff tears are painful, the incidence of asymptomatic rotator cuff tears has been reported to range from 15-39% [3]. However, the influence of asymptomatic rotator cuff pathology on shoulder function is not particularly well understood. Thus, the objective of this study was to assess the effects of asymptomatic rotator cuff pathology on shoulder kinematics, strength, and patient-reported outcomes. METHODS: Following IRB approval, 25 asymptomatic subjects (age: 59±5.5, range: 51-74) with normal shoulder function underwent a clinical ultrasound exam to evaluate their rotator cuff. The ultrasound imaging identified subjects as having an intact rotator cuff (CNTL, n=9, age: 58.1 ± 5.4, range: 51-69) or having asymptomatic rotator cuff pathology ranging from tendinosis to a full-thickness tear (PATH, n=16, age: 59.6 ± 5.7, range: 51-74). For all subjects, in-vivo shoulder motion during frontal-plane elevation was measured using a biplane x-ray system. The 3D position and orientation of the humerus, scapula, and ribs 3 and 4 were measured from biplane x-ray images using model-based tracking (±0.4, 0.5°) [4]. From these data we measured humerothoracic, glenohumeral, and scapulothoracic kinematics [5], glenohumeral joint contact patterns [6], and acromiohumeral distance [7]. Conventional clinical outcomes were assessed by measuring: 1) isometric shoulder strength during abduction (ABD), elevation (ELEV), internal rotation (IR), and external rotation (ER), 2) active and passive ROM during ABD, ELEV, IR, and ER, and 3) patient-reported outcomes using the Western Ontario Rotator Cuff (WORC) score and a visual-analog pain scale (VAS). The effects of rotator cuff pathology on measures of shoulder motion, strength, ROM, and patientreported outcomes were assessed with an unpaired t-test. Significance was set at p=0.05 and statistical trends were set at p=0.10. RESULTS: Conventional clinical outcomes: No significant differences were detected between the CNTL and PATH subjects in average age (p=0.76), composite WORC score (p=0.18), VAS score (p=0.47), or any measure of active or passive ROM (p\u3e0.32). Subjects with rotator cuff pathology had significantly less ABD strength (p=0.03) and a trend for lower ELEV and ER strength (p=0.08), but no difference in IR strength (p=0.22, Fig. 1A). Joint kinematic outcomes: Compared to the CNTL subjects, there were statistical trends for the subjects with asymptomatic rotator cuff pathology a more inferiorly positioned humerus on their glenoid (p=0.06, Fig. 1B) and a more anteriorly tilted scapula (p=0.10, Fig. 1C). No statistically significant differences were detected between the CNTL and PATH subjects in scapulothoracic internal/external rotation ROM (p=0.47), scapulothoracic anterior/posterior tilt ROM (p=0.77), or scapulothoracic upward rotation ROM (p=0.69). Similarly, no significant differences were detected between the CNTL and PATH subjects in the average scapulothoracic internal/external rotation (p=0.56) or average scapulothoracic upward rotation (p=0.92). No differences were detected between the CNTL and PATH subjects in the average (p=0.57) or range (p=0.56) of acromiohumeral distance. DISCUSSION: Although the study failed to detect statistically significant differences between PATH and CNTL subjects in many of the outcome measures, the subtle differences and statistical trends that were observed together suggest a plausible progression of rotator cuff pathology. First, intrinsic supraspinatus tendon degeneration - typically identified clinically as tendinosis - appears to be one of the earliest indications of rotator cuff pathology. We suspect that the degenerated/torn supraspinatus tendon is structurally compromised in a way that prevents it from fully transmitting muscle forces, thus contributing to a decrease in shoulder strength (Fig. 1A). Next, the decrease in sup aspinatus tendon forces leads to subtle GHJ instability, as evidenced by the humerus positioned more inferiorly on the glenoid (Fig. 1B). This subtle instability further exacerbates the issue of decreased shoulder strength, since the GHJ is no longer in an optimal configuration to provide a stable base of support necessary to generate high muscle forces. At some point during the progression of rotator cuff pathology the scapula becomes tilted more anteriorly (Fig. 1C), though it is still unknown if abnormal scapular motion contributes to the development of rotator cuff pathology or is the result of rotator cuff pathology. There is evidence that anterior tilting of the scapula decreases the acromiohumeral distance and, presumably, increases the likelihood of symptoms due to subacromial impingement, but the data reported here suggest that the humerus positioned more inferiorly on the glenoid appears to maintain the acromiohumeral distance. Consequently, the on-going biologic processes associated with rotator cuff tendon degeneration and/or tear propagation are able to proceed in the absence of impingement-related symptoms. Although this mechanism is speculative, it may help to explain why such a high number of rotator cuff tears remain asymptomatic. This mechanism would also suggest that exercises designed to restore normal scapular motion may increase the acromiohumeral distance sufficiently to minimize or eliminate impingementrelated symptoms and the need for surgery. Furthermore, it is possible that some measure of scapular kinematics may be the best predictor of the presence/absence of symptoms in individuals with a rotator cuff tear. Clearly, further research is needed to more precisely understand the relationships between tendon pathology, GHJ motion, scapulothoracic motion, acromiohumeral distance, and the development of symptoms. (Figuer Presented)

The Hyperechoic Appearance of the Deltoid Muscle on Shoulder Ultrasound Imaging as a Predictor of Diabetes and Prediabetes

OBJECTIVES: To evaluate whether the ultrasound appearance of the deltoid muscle in diabetic patients differs from that in obese nondiabetic patients. METHODS: Ultrasound images of the deltoid muscle from 137 type 2 diabetic patients (including 13 prediabetic patients) and 49 obese nondiabetic patients were blindly reviewed by 2 musculoskeletal radiologists, and by a third when arbitration was needed, to determine whether the appearance was normal, suspected diabetes, or definite diabetes. Age, sex, race, body mass index (BMI), insulin use, and hemoglobin A RESULTS: The type 2 diabetic patients included 98 women and 39 men aged 29 to 92 years, and the nondiabetic patients included 19 women and 30 men aged 18 to 75 years. A consensus diagnosis of definite diabetes by the musculoskeletal radiologists based on a hyperechoic deltoid was a powerful predictor of diabetes, with a positive predictive value of 89%. A hyperechoic deltoid was also a powerful predictor of prediabetes. Of the 13 prediabetic patients, all had the same hyperechoic appearance of the diabetic deltoid, regardless of BMI. Although obese diabetic patients more often had a diagnosis of definite diabetes, the BMI alone could not explain the increased echogenicity, as obese nondiabetic patients\u27 deltoid muscles did not appear as hyperechoic and were correctly categorized as not having definite diabetes with 82% specificity. CONCLUSIONS: The characteristic hyperechoic deltoid appearance is a strong predictor of both diabetes and prediabetes and differs from that of obese nondiabetic patients