Diagnostic accuracy of ultrasound for rotator cuff tears

Pseudoparalysis and Pseudoparesis of the Shoulder: Definitions, Management, and Outcomes

Loss of shoulder function can be a complex condition to manage. Specifically, the definition between the terms pseudoparalysis and pseudoparesis remains inconsistent in the literature based on various factors including chronicity, present pathology, and the role of pain in the loss of function. There is also debate as to the optimal management strategies for these challenging conditions. In the setting of advanced glenohumeral arthritis or arthropathy in the correct patient, arthroplasty provides consistent and reliable results. However, in younger patients or the patient without arthritis, arthroplasty may not be the best option. In some cases, addressing pain with biceps procedures, balloon spacer placement, débridement, or others may be appropriate. However, other instances may require attempts at improving shoulder kinematics with procedures such as rotator cuff repair, superior capsular reconstruction, and tendon transfer. In this review, we discuss current definitions for pseudoparalysis and pseudoparesis, in addition to reviewing the indications for the various treatment options and their respective outcomes.

Exploring the integration of diagnostic musculoskeletal ultrasound imaging into clinical practice by physical therapists

BACKGROUND

Musculoskeletal ultrasound (MSK-US) use for diagnostic purposes is expanding in physical therapy practice. Identifying and describing physical therapy-specific approaches to incorporating MSK-US into the evaluation process is needed. Musculoskeletal ultrasound extends the physical exam to allow clinicians to visualize anatomy and pathophysiology both statically and dynamically. Purpose: To document 1) weekly use of diagnostic MSK-US; and 2) clinical reasoning approach used in challenging patient cases by physical therapists (PTs) registered by Inteleos in musculoskeletal sonography (RMSK-certified).

METHODS

Longitudinal, observational, cohort study using mixed methods for data collection and analysis. All 23 currently RMSK-certified PTs using MSK-US in clinical practice across the United States were contacted, and 16 participated. Data were collected using an online survey created with the Research Electronic Data Capture System. Participants documented MSK-US clinical use and significant cases using weekly, reflective, online journals for three months. Demographic data were summarized using descriptive statistics. Case data were analyzed thematically.

RESULTS

Participating RMSK-certified PTs performed 1110 MSK-US examinations over 110 weeks. Clinicians averaged 7 (range 1-25) MSK-US examinations weekly, representing 28% of an average caseload. Examinations contributed significant anatomical/ pathological information 100% of the time. The most common joints scanned were the knee (n = 281), shoulder (n = 254), and wrist (n = 228). Case data revealed three themes: 1) augmenting the clinical evaluation to extend or narrow a diagnosis; 2) outcomes guiding action; and 3) lessons learned from clinical findings.

CONCLUSION

RMSK-certified PTs regularly used MSK-US to validate and refine their clinical diagnoses and treatment. Ultrasound imaging directly influenced patient care by informing the diagnostic process, guiding treatment, and appropriately identifying referrals.

Clinical Applications, Challenges, and Recommendations for Artificial Intelligence in Musculoskeletal and Soft-Tissue Ultrasound: AJR Expert Panel Narrative Review

Artificial intelligence (AI) is increasingly used in clinical practice for musculoskeletal imaging tasks, such as disease diagnosis and image reconstruction. AI applications in musculoskeletal imaging have focused primarily on radiography, CT, and MRI. Although musculoskeletal ultrasound stands to benefit from AI in similar ways, such applications have been relatively underdeveloped. In comparison with other modalities, ultrasound has unique advantages and disadvantages that must be considered in AI algorithm development and clinical translation. Challenges in developing AI for musculoskeletal ultrasound involve both clinical aspects of image acquisition and practical limitations in image processing and annotation. Solutions from other radiology subspecialties (e.g., crowdsourced annotations coordinated by professional societies), along with use cases (most commonly rotator cuff tendon tears and palpable soft-tissue masses), can be applied to musculoskeletal ultrasound to help develop AI. To facilitate creation of high-quality imaging datasets for AI model development, technologists and radiologists should focus on increasing uniformity in musculoskeletal ultrasound performance and increasing annotations of images for specific anatomic regions. This Expert Panel Narrative Review summarizes available evidence regarding AI's potential utility in musculoskeletal ultrasound and challenges facing its development. Recommendations for future AI advancement and clinical translation in musculoskeletal ultrasound are discussed.

The impact of a novel musculoskeletal consult service in an inpatient rehabilitation facility: A descriptive analysis

BACKGROUND

Musculoskeletal (MSK) pathologies significantly affect the rehabilitation course for patients admitted to an inpatient rehabilitation facility (IRF). The impact of a specialized inpatient MSK consult service has not been previously evaluated.

OBJECTIVE

To assess the demographics, pathologies, and impact on pain scores of patients who were evaluated by a specialized MSK consult service.

DESIGN

Retrospective descriptive analysis of patients at an IRF who were evaluated by the MSK consult service.

SETTING

Academic IRF.

PARTICIPANTS

230 patients evaluated by the MSK consult service over 4.5 years.

INTERVENTIONS

MSK consult service composed of sports medicine fellowship-trained physiatrists who use history, physical examination, point-of-care ultrasound, and specialized MSK knowledge to assess and address MSK barriers to functional improvement.

MAIN OUTCOME MEASURES

Primary rehabilitation diagnosis, length of stay, discharge destination, reason for consult, MSK diagnosis, need for injection, change in Numerical Pain Rating Scale (NPRS) pain scores, change in Functional Independence Measures (FIM).

RESULTS

A total of 230 consults met inclusion criteria for analysis. The most common symptoms were shoulder pain (47%), knee pain (30%), and hip/groin pain (10.4%). The MSK consult service made 82 different musculoskeletal and neuromuscular diagnoses. The most common primary rehabilitation diagnosis was stroke (28.3%). Injections were performed in 44.3% of consults, with an average reduction in NPRS pain score of 2.3 (SD 1.9) and a statistically significant reduction in average NPRS pain scores in patients who underwent injections compared to those who did not (p < .001).

CONCLUSIONS

This study is the first to examine the use of an innovative inpatient MSK physiatry consult service in an IRF. This promising consult service can play a pivotal role in patient care by reducing functionally limiting MSK pain to allow for better toleration of therapies and to optimize functional gains.

High-Resolution Imaging Insights into Shoulder Joint Pain: A Comprehensive Review of Ultrasound and Magnetic Resonance Imaging (MRI)

Shoulder joint pain is a complex and prevalent clinical concern affecting individuals across various ages and lifestyles. This review delves into the pivotal role of high-resolution imaging techniques, namely ultrasound and magnetic resonance imaging (MRI), in the comprehensive assessment and management of shoulder joint pain. We explore the anatomical foundations of the shoulder, common etiologies of pain, and the significance of precise diagnosis. High-resolution imaging facilitates the identification of various shoulder pathologies and is crucial in treatment planning, surgical interventions, and long-term prognosis assessment. We examine emerging technologies, discuss challenges and limitations, and chart potential future developments, emphasizing the ongoing evolution of imaging in this critical healthcare domain. In conclusion, high-resolution imaging is an indispensable tool, continually advancing to meet the diagnostic and therapeutic needs of individuals grappling with shoulder joint pain.

Secondary Rotator Cuff Insufficiency After Anatomic Total Shoulder Arthroplasty

» Secondary rotator cuff insufficiency is a challenging complication after anatomic total shoulder arthroplasty.» Acute tears may be amenable to open or arthroscopic repair in some instances.» Chronic attritional tears are best managed with revision to reverse shoulder arthroplasty, especially in the elderly.» Increased glenoid inclination, larger critical shoulder angle, oversized humeral components, thicker glenoid components, and rotator cuff muscle fatty infiltration have all shown to contribute to tear risk.

Delamination of rotator cuff tears: Real-time dynamic ultrasound findings

PURPOSE

The purpose of this study was to evaluate the value of diagnosing delaminated tears and ultrasonic characteristics on real-time dynamic ultrasound.

MATERIALS AND METHODS

We enrolled 143 consecutive patients who underwent arthroscopic rotator cuff repair between April 2020 and January 2021. All patients were examined using real-time dynamic ultrasound of the shoulder within 2 weeks before arthroscopy. In our study, delaminated tears were defined as intratendinous horizontal splitting with or without the retraction of the articular or bursal layer of tendon. Delaminated tears were classified into three types on the basis of their shape: greater retraction of the articular layer (type I), greater retraction of the bursal layer (type II), and equal retraction of both layers (type III). The sensitivity and specificity of real-time dynamic ultrasound for evaluation of delaminated tears were calculated using arthroscopy findings as the gold standard. Ultrasonic imaging appearances of delaminated rotator cuff tears were further described.

RESULTS

Of the 143 patients, 47 (32.9%) had delaminated tears as confirmed by arthroscopy; 35 of these tears involved the supraspinatus tendon and 12 involved both supraspinatus and infraspinatus tendons. Real-time dynamic ultrasound correctly diagnosed 36 of 47 delaminated tears with sensitivity 72.0% (57.2%-83.3%) and specificity 96.7% (90.2%-99.2%). Moreover, type I tear (n = 32) was more common than type II (n = 11) and type III tears (n = 4). Real-time dynamic ultrasound evaluated shape of type I, type II, and type III with a sensitivity and specificity of 56% and 80%, 72% and 83%, and 100% and 98%, respectively. Anechoic horizontal linear splitting of tendon, unequal retraction of the bursal and articular layers, and thinning of the suffering tendon were the three signs observed during real-time dynamic ultrasound examination. These three signs were indicative of a diagnosis of delaminated rotator cuff tears with high specificities (100.0%, 100.0%, and 97.9%, respectively) but relatively low sensitivities (25.5%, 25.5%, and 36.2%, respectively).

CONCLUSION

Real-time dynamic ultrasound can be practically used for diagnosing delamination of rotator cuff tears with medium sensitivity and high specificity. Anechoic horizontal linear splitting of tendon, unequal retraction of the bursal and articular layers, and thinning of the involved tendon are the three important ultrasonic signs for diagnosis of delaminated rotator cuff tears.

A Systematic Temporal Assessment of Changes in Tendon Stiffness Following Rotator Cuff Repair

OBJECTIVES

How the material properties of the human supraspinatus tendon change following arthroscopic rotator cuff repair is undetermined. Shear wave elastography ultrasound is a relatively new, noninvasive measure of tissue stiffness. We aimed to evaluate any temporal changes in stiffness and/or thickness of supraspinatus tendons in humans following primary arthroscopic rotator cuff repair.

METHODS

Shear wave elastography was performed at three predetermined regions by a single sonographer at 1-, 6-, 12-, 24-, and 52 weeks postoperatively in 50 consecutive single-row inverted mattress primary arthroscopic rotator cuff repairs. One-way ANOVA with Tukey's correction and Spearman's correlation tests was performed.

RESULTS

Of 50 patients, two retore by 1-week and were excluded. Two patients retore at 6 weeks, two at 12 weeks, and one at 24 weeks. The mean tendon stiffness in 48 patients at the tendon footprint increased by 21% (1.32 m/s) at 6 months (P < .001), with the lateral tendon stiffening before the medial tendon. Tendon thickness decreased by 11% (0.6 mm) at 6 weeks (P = .008), then stabilized to 24 weeks. Tendons that were less elastographically stiff at 1 week were more likely to be thinner at 6-weeks (r = .38, P = .010).

CONCLUSIONS

The data supports the hypothesis that rotator cuff tendons repaired using the single-row inverted-mattress technique take 6 weeks to heal to bone. Unlike in other tendons, there was no hypertrophic healing response. Prior to 6 weeks, the tendon may stretch/thin-out, particularly if its material properties, as assessed by shear wave elastography, are inferior. The material properties of the tendon improved at the tendon insertion site first, then medially out to 12 months post-repair.

Artificial Intelligence in the Management of Rotator Cuff Tears

Technological innovation is a key component of orthopedic surgery. Artificial intelligence (AI), which describes the ability of computers to process massive data and "learn" from it to produce outputs that mirror human cognition and problem solving, may become an important tool for orthopedic surgeons in the future. AI may be able to improve decision making, both clinically and surgically, via integrating additional data-driven problem solving into practice. The aim of this article will be to review the current applications of AI in the management of rotator cuff tears. The article will discuss various stages of the clinical course: predictive models and prognosis, diagnosis, intraoperative applications, and postoperative care and rehabilitation. Throughout the article, which is a review in terms of study design, we will introduce the concept of AI in rotator cuff tears and provide examples of how these tools can impact clinical practice and patient care. Though many advancements in AI have been made regarding evaluating rotator cuff tears-particularly in the realm of diagnostic imaging-further advancements are required before they become a regular facet of daily clinical practice.

Is Advanced Imaging to Assess Rotator Cuff Integrity Before Shoulder Arthroplasty Cost-effective? A Decision Modeling Study

BACKGROUND

Shoulder arthroplasty is increasingly performed for patients with symptoms of glenohumeral arthritis. Advanced imaging may be used to assess the integrity of the rotator cuff preoperatively because a deficient rotator cuff may be an indication for reverse shoulder arthroplasty (RSA) rather than anatomic total shoulder arthroplasty (TSA). However, the cost-effectiveness of advanced imaging in this setting has not been analyzed.

QUESTIONS/PURPOSES

In this cost-effectiveness modeling study of TSA, all patients underwent history and physical examination, radiography, and CT, and we compared (1) no further advanced imaging, (2) selective MRI, (3) MRI for all, (4) selective ultrasound, and (5) ultrasound for all.

METHODS

A simple chain decision model was constructed with a base-case 65-year-old patient with a 7% probability of a large-to-massive rotator cuff tear and a follow-up of 5 years. Strategies were compared using the incremental cost-effectiveness ratio (ICER) with a willingness to pay of both USD 50,000 and 100,000 per quality-adjusted life year (QALY) used, in accordance with the Second Panel on Cost-Effectiveness in Health and Medicine. Diagnostic test sensitivity and specificity were extracted from published systematic reviews and meta-analyses, and patient utilities were obtained using the Cost-Effectiveness Analysis Registry from the Center for the Evaluation of Value and Risk in Health. Final patient states were categorized as either inappropriate or appropriate based on the actual rotator cuff integrity and type of arthroplasty performed. Additionally, to evaluate the real-world impact of intraoperative determination of rotator cuff status, a secondary analysis was performed where all patients indicated for TSA underwent intraoperative rotator cuff examination to determine appropriate implant selection.

RESULTS

Selective MRI (ICER of USD 40,964) and MRI for all (ICER of USD 79,182/QALY) were the most cost-effective advanced imaging strategies at a willingness to pay (WTP) of USD 50,000/QALY gained and 100,000/QALY gained, respectively. Overall, quality-adjusted life years gained by advanced soft tissue imaging were minimal: 0.04 quality-adjusted life years gained for MRI for all. Secondary analysis accounting for the ability of the surgeon to alter the treatment plan based on intraoperative rotator cuff evaluation resulted in the no further advanced imaging strategy as the dominant strategy as it was the least costly (USD 23,038 ± 2259) and achieved the greatest health utility (0.99 ± 0.05). The sensitivity analysis found the original model was the most sensitive to the probability of a rotator cuff tear in the population, with the value of advanced imaging increasing as the prevalence increased (rotator cuff tear prevalence greater than 12% makes MRI for all cost-effective at a WTP of USD 50,000/QALY).

CONCLUSION

In the case of diagnostic ambiguity based on physical exam, radiographs, and CT alone, having both TSA and RSA available in the operating room appears more cost-effective than obtaining advanced soft tissue imaging preoperatively. However, performing selective MRI to assess rotator cuff integrity to indicate RSA or TSA is cost-effective if surgical preparedness, patient expectations, and implant availability preclude the ability to switch implants intraoperatively.

LEVEL OF EVIDENCE

Level III, economic and decision analysis.

Ultrasonic aspiration for vaccination-related shoulder dysfunction

Background

Chronic shoulder pain occurs rarely after a vaccination and is hypothesized to arise from the effects of unintentional vaccine injection into the subacromial bursa, rotator cuff, capsule or underlying bone. The avascular nature of the rotator cuff, as well as unknown genetic and environmental factors, may predispose to the persistence of pain and disability, referred to as vaccination-related shoulder dysfunction and shoulder injury related to vaccine administration (SIRVA).

Methods

Ultrasonography, sonopalpation and ultrasound-guided anesthetic injections were used to locate the anatomical source of chronic (mean 20, range 8–42 months) shoulder pain after a vaccination in a consecutive series of 5 patients. Subsequently ultrasound-guided ultrasonic aspiration and debridement was performed using a 2.1 mm outer cannula with an inner needle vibrating at 28 kHz. Outcomes were assessed using the Quick Disabilities of the Arm, Shoulder and Hand (QDASH) scale at 2, 4, 12, 24 weeks and 1 year.

Results

The distal infraspinatus and teres minor tendons, their insertions and or the adjacent bone were the source of pain in all 5 patients. The mean QDASH score improved from 65 points to 11 points at 2 weeks (P = 0.001), and to 1 point at 4 weeks after the procedures (P = 0.003). Improvements in pain and function remained stable at 1 year in 3 patients, for at least 24 weeks in 1 patient who died of unrelated causes, and 1 year in 1 patient for posterior shoulder pain who after a pain free interval developed anterior shoulder pain related to his previously asymptomatic osteoarthritis (P = 0.013).

Conclusion

The distal infraspinatus and teres minor tendons, their insertions and adjacent bone are a common source of chronic shoulder pain after a vaccination. Ultrasound-guided ultrasonic aspiration and debridement is a potentially effective treatment for resolving pain and restoring function.

Acromiohumeral distance and supraspinatus tendon thickness in people with shoulder impingement syndrome compared to asymptomatic age and gender-matched participants: a case control study

Background

Shoulder impingement syndrome (SIS) is the most common form of shoulder pain. Conservative and surgical treatments for SIS are often not effective. One such surgical intervention is subacromial decompression, aimed at widening the subacromial space (SAS). A better understanding of the changes in the SAS may help explain the relative ineffectiveness of current interventions.

Objective: To measure the acromiohumeral distance (AHD) and supraspinatus tendon thickness (STT) in people with SIS using a case control study.

Methods

The AHD and STT of 39 participants with SIS ≥3 months and 39 age, gender and dominant arm matched controls were measured using ultrasound imaging. Between-group differences for AHD and STT were compared using t-tests. A linear regression was used to determine if there was a relationship between AHD and STT measures, with group as a covariate.

Results

Compared to controls (mean age 55.7 years, SD 10.6), individuals with SIS (mean age 57.1 years, SD 11.1) had a significantly larger AHD (mean difference 2.14 mm, 95% CI 1.21, 3.07, p < 0.001) and STT (mean difference 1.25 mm, 95% CI 0.60, 1.90, p < 0.001). The linear regression model indicated an association between AHD and STT (β = 0.59, 95% CI 0.29, 0.89, p < 0.01, R² = 0.35, n = 78), suggesting that as STT increases in size, so does the AHD.

Conclusion

Individuals with SIS had a larger AHD and greater STT than controls. These results suggest the SAS is already wider in people with SIS and that the symptoms associated with SIS may be more related to an increased STT than a smaller SAS.

The fate of sutures post rotator cuff repair

BACKGROUND

Ultrasonographic imaging has been widely used as a diagnostic tool for rotator cuff tears. Several studies have explored the changes in rotator cuff tendon morphology after arthroscopic cuff repair; however, none have addressed the fate of sutures. The aim of this study was to determine (1) if the sutures migrate through the tendon during the postoperative healing period in patients who have had arthroscopic rotator cuff repair; (2) if the sutures do migrate, the time point at which it does; and (3) if the quality of the tendon, in terms of tendon stiffness, modulus of elasticity, bursal thickness, and anatomic footprint, affects suture migration.

METHODS

This was a prospective study involving 21 patients who had primary arthroscopic rotator cuff repair performed by a single surgeon. All patients were assessed at 8 days, 6 weeks, 12 weeks, and 24 weeks postrepair; during each assessment, patients underwent an ultrasonographic examination (using a Siemens ACUSON S3000 ultrasonographic system, following a standardized protocol), where supraspinatus tendon thickness and thickness of tendon tissues below and above the suture were measured. Measurements of anatomic footprint, bursal thickness, tendon stiffness, and modulus of elasticity were obtained to assess tendon quality.

RESULTS

Of the 21 participants, 14 (67%) had full-thickness tears and 7 (33%) had partial-thickness tears. Between the 12th- and 24th-week follow-up, 2 patients' tendons were found to be not intact. Within the first 12 weeks of the postrepair healing period, the sutures migrated inferiorly, through to the middle of the tendon at the footprint-articular junction (ie, ratio of tendon tissue thickness below the suture to the total tendon thickness = 0.5) (P = .03). The mean anatomic footprint increased from 8.4 ± 1.6 mm to 9.1 ± 1.2 mm between 8 days and 6 weeks (P = .04); bursal thickness decreased during the 24-week period from 1.5 ± 0.9 mm to 0.7 ± 0.4 mm (P = .005); tendon modulus of elasticity increased from 154 ± 75 kPa to 205 ± 96 kPa between 8 days and 24 weeks (P = .05).

DISCUSSION

This is the first study to investigate suture position and migration post arthroscopic rotator cuff repair. The findings of this study suggest that sutures migrating to the middle of the tendon during the postoperative healing process is a normal phenomenon observed on ultrasonography.

Diagnostic Accuracy of Ultrasonography for Rotator Cuff Tears: A Systematic Review and Meta-analysis

Background

With recent improvements in transducer strength, image resolution, and operator training, ultrasound (US) provides an excellent alternative imaging modality for the diagnosis of rotator cuff tears.

Purpose

To evaluate the diagnostic accuracy of US for partial- and full-thickness rotator cuff tears and biceps tendon tears, compare diagnostic values with those of magnetic resonance imaging (MRI) using arthroscopy as the reference standard, assess longitudinal improvements in accuracy, and compare diagnostic values from operators with different training backgrounds.

Study Design

Systematic review; Level of evidence, 3.

Methods

The PubMed and Cochrane Library databases were systematically searched for full-text journal articles published between January 1, 2010, and April 1, 2020. The inclusion criteria were studies that evaluated the diagnostic accuracy of US for rotator cuff tears or biceps tendon tears utilizing arthroscopy as the reference standard. The exclusion criteria were studies with <10 patients, studies including massive tears without reporting diagnostic data for specific tendons, and studies lacking diagnostic outcome data. Extracted outcomes included diagnostic accuracy, sensitivity, specificity, negative predictive value, and positive predictive value. The mean difference and 95% confidence interval were calculated for both US and MRI diagnostic values, and meta-analysis was conducted using the Mantel-Haenszel random-effects model.

Results

In total, 23 eligible studies involving 2054 shoulders were included. US demonstrated a higher median diagnostic accuracy for supraspinatus tendon tears (0.83) and biceps tendon tears (0.93) as compared with subscapularis tendon tears (0.76). US was found to have a higher median accuracy (0.93) for full-thickness supraspinatus tears than partial-thickness tears (0.81). US had superior median sensitivity for partial-thickness supraspinatus tears when performed by radiologists as opposed to surgeons (0.86 vs 0.57). Meta-analysis of the 5 studies comparing US and MRI demonstrated no statistically significant difference in diagnostic sensitivity, specificity, or accuracy for any thickness supraspinatus tears (P = .31-.55), full-thickness tears (P = .63-.97), or partial-thickness tears (P = .13-.81).

Conclusion

For experienced operators, US is a highly sensitive and specific diagnostic modality for the diagnosis of supraspinatus tears and demonstrates statistically equivalent capability to MRI in the diagnosis of both full- and partial-thickness rotator cuff tears.

Ultrasound in Sports Injuries

Utilization of musculoskeletal ultrasound, in particular for sports medicine, has dramatically increased in recent years. Ultrasound is an important adjunct tool to physical examination and other imaging methods in the evaluation and management of the injured athlete. It offers unique advantages in specific clinical scenarios. Dedicated training and a standardized scanning technique are important to overcome the inherent operator dependence and avoid diagnostic pitfalls. Ultrasound guidance can also improve accuracy in targeted percutaneous injection therapies. This article reviews the general ultrasound appearance of muscle, tendon, ligament, and nerve abnormalities in the athlete with a focus on sport-specific injuries.

Diagnostic Accuracy of Musculoskeletal Ultrasound on Long Head Biceps Tendon Pathologies

Clinical Scenario: Pathologies of the long head of the biceps brachii (LHB) tendon are a source of shoulder pain in many people. It is important to have a reliable assessment of the LHB tendon to make an accurate diagnosis and provide the correct treatment or referral if necessary. Shoulder ultrasound is very accurate in the diagnosis of rotator cuff tears. However, its ability to detect pathologies of the LHB tendon is still unclear. Clinical Question: In patients with shoulder pain, can musculoskeletal ultrasound accurately diagnose LHB tendon pathologies? Summary of Key Findings: Four high-quality cohort studies met inclusion criteria and were included in the critical appraisal. The STrengthening the Reporting of OBservational studies in Epidemiology checklist was used to score the articles on methodology and consistency. Three studies evaluated accuracy in diagnosis of full-thickness tears and found high sensitivity (SN) and specificity (SP). Three studies evaluated accuracy in diagnosis of partial-thickness tears and found low SN and negative predictive value, but high SP and positive predictive value. Two studies evaluated tendon subluxation/dislocation and found high SN and SP. Two studies evaluated tendinitis and found moderate SN and high SP. Clinical Bottom Line: There is moderate to strong evidence to support the use of musculoskeletal ultrasound in diagnosis of LHB tendon pathology. Strength of Recommendation: There is grade B evidence that musculoskeletal ultrasound can accurately diagnose full-thickness tears and tendon subluxation/dislocation; can rule in partial-thickness tears (based on SP and positive predictive value), but not rule out partial-thickness tears; and can rule in tendinitis (based on SP and positive predictive value), but not rule out tendinitis.

Imbalanced Loss-Integrated Deep-Learning-Based Ultrasound Image Analysis for Diagnosis of Rotator-Cuff Tear

A rotator cuff tear (RCT) is an injury in adults that causes difficulty in moving, weakness, and pain. Only limited diagnostic tools such as magnetic resonance imaging (MRI) and ultrasound Imaging (UI) systems can be utilized for an RCT diagnosis. Although UI offers comparable performance at a lower cost to other diagnostic instruments such as MRI, speckle noise can occur the degradation of the image resolution. Conventional vision-based algorithms exhibit inferior performance for the segmentation of diseased regions in UI. In order to achieve a better segmentation for diseased regions in UI, deep-learning-based diagnostic algorithms have been developed. However, it has not yet reached an acceptable level of performance for application in orthopedic surgeries. In this study, we developed a novel end-to-end fully convolutional neural network, denoted as Segmentation Model Adopting a pRe-trained Classification Architecture (SMART-CA), with a novel integrated on positive loss function (IPLF) to accurately diagnose the locations of RCT during an orthopedic examination using UI. Using the pre-trained network, SMART-CA can extract remarkably distinct features that cannot be extracted with a normal encoder. Therefore, it can improve the accuracy of segmentation. In addition, unlike other conventional loss functions, which are not suited for the optimization of deep learning models with an imbalanced dataset such as the RCT dataset, IPLF can efficiently optimize the SMART-CA. Experimental results have shown that SMART-CA offers an improved precision, recall, and dice coefficient of 0.604% (+38.4%), 0.942% (+14.0%) and 0.736% (+38.6%) respectively. The RCT segmentation from a normal ultrasound image offers the improved precision, recall, and dice coefficient of 0.337% (+22.5%), 0.860% (+15.8%) and 0.484% (+28.5%), respectively, in the RCT segmentation from an ultrasound image with severe speckle noise. The experimental results demonstrated the IPLF outperforms other conventional loss functions, and the proposed SMART-CA optimized with the IPLF showed better performance than other state-of-the-art networks for the RCT segmentation with high robustness to speckle noise.

Quantitative Evaluation of Rotator Cuff Tears Based on Non-linear Statistical Analysis of Ultrasound Radiofrequency Signals

There is increasing clinical requirement for early and accurate ultrasound diagnosis of rotator cuff tears (RCTs). A method based on non-linear statistical analysis was proposed for the detection of RCTs using ultrasound radiofrequency (RF) signals. One hundred fifty-two patients with shoulder pain were first examined with ultrasound and then diagnosed with magnetic resonance imaging (MRI) as the ground truth. By comparison of the region of interest (ROI) with a part of the supraspinatus with no pathologic change part in the same RF signal frame, the relative P_ks value (viz., rP_ks value) was evaluated to quantify the pathophysiologic changes. The results indicated that the rP_ks values of all RCTs are <0.7, and the accuracy, sensitivity and specificity of the proposed method can reach 97.5%, 100% and 91.4%, respectively. This computer-aided method was found to perform better diagnostic than the results reported by an experienced radiologist (accuracy = 75.7%, sensitivity = 72.6%, and specificity = 85.7%). The high sensitivity advantage of this method indicates that the prospects for its application in the computer-aided diagnosis of RCTs are good.

Accuracy and Reliability of Imaging Modalities for the Diagnosis and Quantification of Hill-Sachs Lesions: A Systematic Review

PURPOSE

To determine the reliability and accuracy of different imaging modalities in assessing Hill-Sachs lesions within the setting of anterior shoulder instability.

METHODS

A systematic review was performed according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyses) guidelines using the PubMed, Scopus, Embase, and Cochrane Library databases. The inclusion criteria were clinical trials or cadaveric studies that assessed the accuracy of humeral head bone loss imaging or reliability and English-language articles. The exclusion criteria were animal studies; imaging studies without measures of accuracy, reliability, or clinical predictive power; studies of shoulder injuries without humeral head bone loss; editorials; abstracts; reviews; case reports; and surveys. The search terms included "imaging" OR "radiographic" OR "CT" OR "MRI" AND "Hill-Sachs" OR "humeral head bone loss." Assessment of the methodologic quality of the included studies was performed using the original Quality Assessment of Diagnostic Accuracy Studies (QUADAS) tool.

RESULTS

Forty studies (2,560 shoulders) met the inclusion criteria and were assessed. For diagnosing the presence of Hill-Sachs lesions, computed tomography (CT) arthrography had the highest reported accuracy (median, 91%; range, 66%-100%). For the same assessment, CT arthrography also had the greatest reported sensitivity (median, 94%; range, 50%-100%). For the quantification of Hill-Sachs lesion parameters, reported intraobserver reliabilities were highest for 3-dimensional (3D) CT (intraclass correlation coefficient [ICC] range, 0.916-0.999), followed by 2-dimensional CT (ICC range, 0.858-0.861) and magnetic resonance imaging (MRI) (ICC range, 0.28-0.97). For the same quantification parameters, interobserver reliabilities were also reported for 3D CT (ICC range, 0.772-0.996), 2-dimensional CT (ICC range, 0.721-0.879), and MRI (κ range, 0.444-0.700). Intraobserver reliabilities for determining glenoid tracking were only reported for 3D CT (κ range, 0.730-1.00; ICC range, 0.803-0.901) and MRI (ICC range, 0.770-0.790).

CONCLUSIONS

This study shows that the current literature supports a variety of different imaging modalities that provide clinically acceptable accuracy in diagnosing and quantifying Hill-Sachs lesions, as well as determining whether they will cause persistent anterior shoulder instability. Furthermore, this systematic review justifies that further research is needed to help develop a treatment algorithm on the proper imaging modalities needed to help treat patients with anterior shoulder instability that is both reliable and financially acceptable.

LEVEL OF EVIDENCE

Level IV, systematic review of Level I through IV studies.

Ultrasound Findings Aid Decisions to Repair Partial Articular Supraspinatus Tendon Avulsion

OBJECTIVES

Ultrasound (US) is useful for diagnosing full-thickness rotator cuff tears and high-grade partial-thickness bursal-side tears. However, anisotropy artifacts make it difficult to identify partial articular supraspinatus tendon avulsion (PASTA) by US. This study was performed to determine the diagnostic accuracy of US for PASTA and to uncover sensitive findings that could aid decisions to repair.

METHODS

Patients who underwent preoperative US examinations and supraspinatus tendon confirmation by arthroscopic examinations were enrolled. We analyzed 52 PASTA cases involving greater than 50% thickness of the tendon and 52 age- and sex-matched cases with an intact supraspinatus. Two orthopedic surgeons blinded to the diagnosis interpreted US videos of the supraspinatus tendon. Six findings (echo defect, tendon delamination, echo change, tendon thickness, tendon fiber pattern, and cartilage interface sign) were assessed. We calculated the sensitivity, specificity, and accuracy for each US finding.

RESULTS

The cases consisted of 46 men and 58 women. The US diagnosis of PASTA showed sensitivity of 64.7%, specificity of 94.1%, and accuracy of 79.4%. The echo change in the short axis showed the highest sensitivity. Thinning and delamination showed the highest specificity of 100%. In contrast to previous reports, the sensitivity of the cartilage interface sign was low in both long-axis images (17.6%) and short-axis images (29.4%).

CONCLUSIONS

Preoperative diagnostic US to aid decisions regarding PASTA repair showed high specificity (94.1%) and moderate accuracy (79.4%). However, the sensitivity was only 64.7% and was affected by the examiner's experience with US.