The Potential of Ultrasound: Earlier Noninvasive Type 2 Diabetes Mellitus Detection

Are you aware that type 2 diabetes mellitus (T2D) affects approximately 537 million adults worldwide, including 37.3 million in the USA? That is over 10% of the U.S. population! Approximately 79% of the people worldwide with T2D are underserved, underrepresented, impoverished, in lower socioeconomic communities, and in developing countries. Furthermore, the worldwide prevalence of T2D is expected to reach an astonishing 783 million by 2045.1–8

Even more shocking is that approximately 50% (232 million) of those people with T2D worldwide are unaware and undiagnosed! This is a major problem since, when T2D is finally detected, at the time of diagnosis, nearly one-half already have one or more irreversible complications resulting in an at least $966 billion global economic burden.

Also, a vast 81% with prediabetes (PreD), more than 77 million in the USA, are undiagnosed and unaware. However, in PreD, earlier lifestyle modifications reduce the risk of developing T2D by greater than 50%. These high numbers of undiagnosed people may be secondary to the lower accuracy of current screening methods in certain conditions and specific populations.

T2D leads to multiple costly serious end-organ complications, including being the leading cause of both end-stage renal disease and non-traumatic lower extremity amputations. Earlier detection is critical as earlier effective glycemic management reduces the risk of associated ophthalmologic, renal, and neurologic diseases by 40%. The urgency of this important matter has even prompted the United States Preventive Services Task Force to update guidelines in 2021 to help improve earlier T2D and PreD detection.1,3,4,9,10

Given its advantages over MRI, including low cost and portability, musculoskeletal (MSK) ultrasound (US) utilization, especially shoulder US, has significantly increased over the past few decades. Shoulder US is often performed on patients with T2D, given the high prevalence of T2D in society and the increased risk of rotator cuff pathology and adhesive capsulitis in individuals with T2D.9,10

As MSK US use increases, a unique opportunity arises for detecting T2D in those unaware, undiagnosed, and presenting for (seemingly) unrelated care. It is our experience and confirmed in our prior publications9,10 that the incidental detection of a hyperechoic deltoid muscle, on routine shoulder US (Figure 1), has on many occasions resulted in the incidental identification of undiagnosed T2D and even PreD. This abnormality was seen in those with and without obesity. Also, in those uncertain of their T2D status or told they were ‘borderline’, most were not treated, despite having this characteristic US deltoid muscle abnormality. Initial experiments also suggest that the hyperechoic deltoid muscle appearance may predate the elevation of HbA1c levels.

Figure 1. Long-axis US image of the right shoulder. a, Normal appearance of a hypoechoic deltoid muscle (solid arrow) in a 43-year-old woman without T2D or PreD. b, Abnormal hyperechoic deltoid (solid arrow) in a 47-year-old woman with T2D. The empty arrows indicate the supraspinatus tendon inserting on the greater tuberosity (arrowheads).

Skeletal muscle insulin resistance is thought to be the primary defect in T2D development, often occurring decades before β-cell failure and apparent metabolic dysfunction.11 Could this earlier-identified skeletal muscle US abnormality represent the noninvasive detection of early muscle insulin resistance and dysfunction, prior to clinically apparent metabolic dysfunction?

We continue to study this novel sonographic abnormality prospectively, including using histologic analyses. We expect our studies will help elucidate this US skeletal muscle abnormality, which could represent the earlier detection of muscle insulin resistance and dysfunction. This could initiate further studies on earlier noninvasive T2D detection, prevention, treatment, and targeted therapies for potential reversal.

References

1.         International Diabetes Federation. IDF diabetes atlas [Internet]. 10th ed. Brussels, Belgium: International Diabetes Foundation; 2021 [cited October 17, 2023].

2.         Centers for Disease Control and Prevention. National Diabetes Statistics Report website. [Internet]. Atlanta (GA): Centers for Disease Control and Prevention, U.S. Department of Health and Human Services; 2022 [updated June 29, 2022; cited October 17, 2023]. 

3.         National Center for Chronic Disease Prevention and Health Promotion, Center for Disease Control and Prevention. Cost-effectiveness of diabetes interventions [Internet]. Atlanta (GA): Centers for Disease Control and Prevention; 2022 [updated December 1, 2022; cited October 17, 2023].

4.         US Preventive Services Task Force, Davidson KW, Barry MJ, Mangione CM, et al. Screening for prediabetes and type 2 diabetes: US Preventive Services Task Force recommendation statement. JAMA 2021; 326:736–743. PMID: 34427594.

5.         Boyle JP, Honeycutt AA, Narayan KM, et al. Projection of diabetes burden through 2050: impact of changing demography and disease prevalence in the U.S. Diabetes Care 2001; 24:1936–1940. PMID: 11679460.

6.         Lin J, Thompson TJ, Cheng YJ, et al. Projection of the future diabetes burden in the United States through 2060. Popul Health Metr 2018; 16(1):9. PMID: 29903012; PMCID: PMC6003101.

7.         Rowley WR, Bezold C, Arikan Y, Byrne E, Krohe S. Diabetes 2030: insights from yesterday, today, and future trends. Popul Health Manag 2017; 20(1):6–12. PMID: 27124621; PMCID: PMC5278808.

8.         National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health. Diabetes [Internet]. Bethesda (MD): National Institute of Diabetes and Digestive and Kidney Diseases; 2021 [cited October 17, 2023].

9.         Soliman SB, Rosen KA, Williams PC, et al. The hyperechoic appearance of the deltoid muscle on shoulder ultrasound imaging as a predictor of diabetes and prediabetes. J Ultrasound Med 2020; 39:323–329. PMID: 31423604. https://onlinelibrary.wiley.com/doi/10.1002/jum.15110.

10.       Rosen KA, Thodge A, Tang A, Franz BM, Klochko CL, Soliman SB. The sonographic quantitative assessment of the deltoid muscle to detect type 2 diabetes mellitus: a potential noninvasive and sensitive screening method? BMC Endocr Disord 2022; 22(1):193. PMID: 35897066.

11.       DeFronzo RA, Tripathy D. Skeletal muscle insulin resistance is the primary defect in type 2 diabetes. Diabetes Care 2009; 32(Suppl 2):S157–S163. PMID: 19875544; PMCID: PMC2811436.

Steven B. Soliman, DO, RMSK, FAOCR, is an associate professor and musculoskeletal radiologist at the University of Michigan.

Interested in reading more about MSK ultrasound? Check out these posts from the Scan:

The Game-Changing Use of Ultrasound on the Sideline: Revolutionizing Sports Medicine

In the world of sports, injuries are an unfortunate reality that athletes must face. Rapid and accurate diagnosis is crucial to ensure timely treatment and minimize downtime. Traditionally, athletes would have to undergo imaging scans off-site, resulting in delays and limited access to immediate medical care. However, with recent advancements in medical technology, ultrasound has emerged as a game-changing tool. The terms, “venue ultrasound” and “sideline ultrasound” refer to the use of ultrasonography at a sports venue, in a stadium, on the sideline of a sporting event, or in the athletic training room. Its portability and real-time imaging capabilities make it an invaluable asset for sports medicine providers. In fact, the pilot investigation using venue ultrasound at the 2020 Tokyo Olympic Games was successful in diagnosing injuries among athletes.1

Portable and Convenient
Ultrasound technology has undergone significant advancements, making it more compact, portable, and user-friendly. Modern handheld ultrasound devices are lightweight, battery-operated, and can be easily transported to sporting events or training facilities. This portability allows medical professionals to perform immediate on-site evaluations, enabling faster diagnosis and treatment decisions. The technology continues to evolve with many pocket-sized, handheld devices by leading manufacturers. Examples include the Philips Lumify, GE Vscan, Sonosite iViz, Butterfly iQ, Viatom, and Clarius. In addition, many of the units allow for easy wireless exchange of images and remote access by off-site professionals, if further assistance is needed.

Real-Time Imaging
One of the most significant advantages of sideline or venue ultrasound is its ability to provide real-time imaging. Unlike other imaging modalities, such as X-ray (XR) or magnetic resonance imaging (MRI), which require athletes to wait for results, ultrasound allows for immediate visualization of internal structures. This real-time feedback empowers medical staff to make quick and accurate diagnoses, as well as enables expedited triage of acute athlete conditions. This is particularly useful when XR is not readily available, which is commonplace at many events, particularly non-stadium venues.

Injury Assessment and Diagnosis
Portable handheld ultrasound devices can accurately assess soft tissue injuries, detect fractures, evaluate joint stability, and identify potential nerve or vascular involvement. During the last Olympics, ultrasound showed 100% accuracy in cases that underwent confirmatory imaging.1 In the emergency department (ED), which can be a similar setting to the sports sideline, point-of-care ultrasound (POCUS) enables appropriate medical decision-making using real-time imaging. Applications of POCUS for musculoskeletal conditions in the ED include joint effusions, long bone fractures, and muscle and tendon injuries.2 Long bone fractures can be excluded and tendon injuries can be diagnosed by physicians in the ED using POCUS with high sensitivity and specificity.3,4 Further, POCUS in the ED positively impacts medical decision-making for musculoskeletal complaints.5

Monitor Healing
Once an injury has occurred, ultrasound can be used to monitor the healing progress during the rehabilitation phase. Regular ultrasound assessments allow medical staff to evaluate tissue repair, assess the formation of scar tissue, and track the restoration of normal function. This real-time monitoring provides valuable insights into an athlete’s recovery trajectory, enabling adjustments to treatment plans as needed. This can be particularly helpful in athletic training room situations in determining time to return to play.6

Additional Applications
Sideline ultrasound has numerous applications in the care of athletes, including trauma assessments and guided injections. One notable application is the Focused Assessment with Sonography for Trauma (FAST) exam, which is a POCUS examination used to evaluate potential internal injuries, particularly within the abdomen and chest, in the context of acute trauma. While the FAST exam has more traditionally been utilized in the ED, it is becoming increasingly popular on the sideline. The exam involves using ultrasound to evaluate specific regions of the body quickly, aiding in the identification of potential organ damage or bleeding. It allows for rapid assessment and triage regarding further medical interventions or necessary actions. Meanwhile, ultrasound-guided injections and interventions have long been an essential component of sports medicine. The addition of ultrasound guidance enables medical providers to be more targeted in their treatments.

Limitations and Future Directions
While venue ultrasound has enhanced sports medicine, it is essential to acknowledge its limitations. The depth of penetration, image quality, time from injury, and operator dependence can impact the accuracy of diagnoses. Continued advancements in technology and ongoing training for sports medicine professionals are crucial to maximize the potential of sideline ultrasound.

Conclusion
The use of ultrasound on the sideline has revolutionized sports medicine, enabling rapid and accurate diagnosis of injuries. Its portability, real-time imaging capabilities, and dynamic ability to assess musculoskeletal injuries make it an invaluable tool for healthcare professionals on the sideline and in the training room. With further advancements, ultrasound’s role in sports medicine is poised to continue expanding, benefiting athletes worldwide by providing more immediate and personalized care. For further information on this topic, consider reviewing the AIUM webinar, Sideline Ultrasound (https://www.youtube.com/watch?v=aX-AibSfctc).

Robert Monaco and Lauren Rudolph.
Robert Monaco, MD, MPH, RMSK, is a physician at Atlantic Sports Health and is a team physician for USA Figure Skating. Lauren Rudolph, MD, is a physician at Boulder Biologics, adjunct faculty for ultrasound education at Rocky Vista University, and a traveling physician with the US Ski team.

References:

  1. Onishi K, Engebresten L, Budgett R, Soligard T, Forster BB. The International Olympic Committee venue ultrasound program: A pilot study from Tokyo 2020 Olympic Games. Am J Phys Med Rehabil 2023; 102:449–453. 
  2. Chen KC, Lin A, Chong CF. et al. An overview of point-of-care ultrasound for soft tissue and musculoskeletal applications in the emergency department. J Intensive Care 2016; 4:55.
  3. Waterbrook AL, Adhikari S, Stolz U, Adrion C. The accuracy of point-of-care ultrasound to diagnose long bone fractures in the ED. Am J Emerg Med 2013; 31:1352–1356.
  4.  Wu TS, Roque PJ, Green J, et al. Bedside ultrasound evaluation of tendon injuries. Am J Emerg Med 2012; 30:1617–1621.
  5. Situ-LaCasse E, Grieger RW, Crabbe S, Waterbrook AL, Friedman L, Adhikari L. Utility of point-of-care musculoskeletal ultrasound in the evaluation of emergency department musculoskeletal pathology. World J Emerg Med 2018; 9:262–266.
  6. Bailowitz Z, Visco C, Christen K, Ahmad C. Diagnostic musculoskeletal ultrasound for the acute evaluation and management of soccer players. Curr Sports Med Rep 2021; 20: 525–530.

The Power of Ultrasound in Physiotherapy

In incredible ways, ultrasound has revolutionized the path to recovery for patients with soft tissue damage and enhanced the patients’ overall well-being. It is a cutting-edge therapeutic technique that harnesses the power of sound waves to stimulate deep tissues, accelerate healing, and alleviate pain. Through its mechanical vibrations, ultrasound effectively increases blood flow, reduces inflammation, and enhances the flexibility of muscles and tendons. This noninvasive modality has significantly impacted the field of physiotherapy.

The Benefits of Ultrasound in Physiotherapy

  1. Accelerated Healing: The primary benefit of ultrasound therapy is its ability to expedite the healing process. By encouraging collagen production, ultrasound facilitates the repair of tissues, enabling faster recovery from various injuries and conditions. Witnessing the speed at which a body can regenerate and mend itself is truly remarkable.
  2. Pain Relief: Dealing with pain can be physically and mentally debilitating. Thankfully, ultrasound therapy can provide immense relief. By stimulating sensory nerves, this modality effectively alleviates pain, allowing a runner to focus on their recovery and regain their quality of life.
  3. Improved Circulation: Optimal blood circulation is vital for the healing process. Ultrasound therapy can be instrumental in enhancing circulation, ensuring that oxygen and essential nutrients reach the damaged tissues more efficiently. As a result, inflammation reduces, and overall healing is optimized.
  4. Enhanced Mobility and Flexibility: A lack of mobility and flexibility can hinder daily activities and impact overall well-being. Ultrasound therapy can cause significant improvements in these areas. The targeted sound waves promote soft tissue mobilization, increasing flexibility and range of motion. This newfound freedom of movement has been a game-changer for many patients.
  5. Noninvasive and Safe: One of the most appealing aspects of ultrasound therapy is its noninvasive nature. Patients can receive effective treatment without the need for surgical interventions or invasive procedures. This not only minimizes downtime but also provides peace of mind for the patient, who knows that they are undergoing a safe and risk-free therapy.

Incorporating Ultrasound Into Physiotherapy Sessions

During physiotherapy sessions, the utilization of ultrasound therapy can be a straightforward and comfortable experience. The physiotherapist applies a gel to the targeted area and gently moves a handheld transducer over the skin. The transducer emits therapeutic sound waves, which penetrate deep into the tissues, providing the desired benefits. The duration and frequency of ultrasound treatment are tailored to the patient’s specific needs, ensuring optimal results.

It is crucial to emphasize that ultrasound therapy should always be administered by trained professionals who can customize the treatment according to individual requirements, and can take into account any contraindications. Physiotherapists conduct thorough assessments and develop personalized treatment plans that may include a combination of ultrasound therapy, stretching exercises, strengthening routines, and other complementary techniques.

Ultrasound is a transformative, revolutionary therapy in the realm of physiotherapy. Through its ability to accelerate healing, alleviate pain, improve circulation, and enhance mobility, ultrasound has become an indispensable tool in the journey toward improved well-being. If you are considering physiotherapy or seeking effective treatment options, I highly encourage you to explore the incredible benefits of ultrasound therapy. Consult with a qualified physiotherapist who can review your case and determine whether it is in your best interest to experience the remarkable healing potential of ultrasound firsthand.

Interested in learning more about ultrasound in physiotherapy? Check out the following articles from the American Institute of Ultrasound in Medicine’s (AIUM’s) Journal of Ultrasound in Medicine (JUM). Members of AIUM can access them for free after logging in to the AIUMJoin the AIUM today!

And, check out this post from the Scan:

Cynthia Owens, BA, is the Publications Coordinator for the American Institute of Ultrasound in Medicine (AIUM).

Preventing Work-Related Musculoskeletal Disorders Among Ultrasound Operators

Up to 90% of sonographers and other operators of diagnostic medical sonography report having painful work-related injuries affecting the muscles, nerves, ligaments, or tendons.1 These work-related musculoskeletal disorders (WRMSDs) result from the multiple times a day the operators repeatedly make the same movements and maneuvers while performing ultrasound examinations.2 For the ultrasound operator, the most common locations of WRMSDs include the shoulder, neck, wrist, and hands, and the results of WRMSDs can lead to serious health issues, absenteeism, presenteeism, and even leaving the field of ultrasound altogether.3

The following are some of the critical factors that can lead to the development of WRMSDs:

  • Poor ergonomics, including poor posture and machines with poor ergonomic design.3
  • Poor workflow, including the positions of the machine, bed, and workstation, leads to unnecessary arm abduction and overreaching.3
  • Lengthy exams with an increasing workload and number of exams to be performed during the workday.4
  • Inadequate breaks between examinations in addition to an increasing workload.5
  • Psychological stress and psychosocial factors in the workplace.6
  • Unsupportive or inflexible environments that fail to account for the diverse abilities and experiences of individual operators.7

The Occupational Safety and Health Administration has placed the primary responsibility for protecting workers on the employer.8,9 So, when developing WRMSD prevention protocols, administrators should collaborate with ultrasound operators to create policies that support their safety.10 Such policies should take into account scheduling to limit overtime work and provide breaks, staffing levels to optimize patient care, proper ergonomic equipment and adjustable equipment, and room designs that facilitate proper ergonomics, such as adequate space for patients and equipment. The workplace culture should support wellness and also have transparent policies regarding reporting and tracking of WRMSDs.

The operator also needs to ensure their working space is set up in the best manner possible for preventing WRMSDs during their workday. They can do so by customizing their ultrasound environment to promote proper ergonomic technique.

  1. At the beginning of each examination, the operator should properly position and make adjustments depending upon the body habitus of each patient.11 Reaching movements should be avoided by keeping the operator, machine, bed, and patient as close together as possible and at appropriate heights.
  2. The operator’s head and the screen/monitor should be on the same axis, and the eye-screen distance should be at least 60 cm. The top of the screen should be aligned with the level of the operator’s eyes; then, the top of the screen should be tilted back slightly to encourage proper neck posture.11,12
  3. The operator’s neck should be straight, and neck extension should be avoided.6
  4. The operator should be positioned in order to allow the arm to be in a relaxed position with the upper arm close to the body (minimal flexion, ideally abduction <30 degrees) and the elbow at a 90-degree angle, ie, the forearm should be horizontal to the floor allowing the shoulder to remain in a neutral positionwhenever possible.
  5. A “wearable transducer cable support device,”13 such as a cable brace, can be utilized to reduce arm strain during scanning. Also, the ultrasound transducer cable should not be passed around the operator’s neck as any traction force could result in a poor neck position.11,12
  6. A scanning chair should be equipped with a backrest for lumbar support and adjustable height to mold the lumbar lordosis. Moreover, a seatback inclined between 10° and 20° is recommended. The back should be well supported on the seat. A slight gap should remain between the edge of the seat and the back of the knee, and the body should be on the axis of the screen. The chair should be height adjustable so the operator can be properly positioned relative to the patient and ultrasound system. Exam chairs should not have armrests as they may restrict access to the patient.
  7. Exam tables should be height adjustable to encourage proper positioning by minimizing extended reaching, elevated arms, and wrist deviation, and allowing operators to stand and/or sit while performing procedures.
  8. The ultrasound machine keyboard should be easy to move and adjust.
  9. Removing the transducer from the patient and relaxing the hand to allow for brief micro-breaks during the examination can help reduce muscle strain.
  10. With the exception of point-of-care imaging, portable diagnostic exams should be limited to critically ill patients and those patients who are unable to come to the ultrasound department.

Specific types of ultrasound examinations also bring unique challenges. Some of these challenges are addressed, by specialty, in the AIUM Practice Principles for Work-Related Musculoskeletal Disorder.14

Increased awareness of the magnitude of the problem and local quality improvement (QI) efforts are necessary to ensure that these standards are translated into the successful reduction of WRMSDs among ultrasound operators.

A QI program should include ongoing tracking or logging of the following:

  • Ergonomic education for employees
  • Safety and resource utilization
  • Equipment updates
  • The numbers and types of reported symptoms and/or injuries, and
  • Organizational (ie, policies and practices) changes or updates made to improve employee safety and well-being.

A review of these data, along with a status check on overall workplace culture and worker well-being, should be conducted annually. To do so, a QI team composed of individuals from all levels of the organization (eg, administration, management, staff) should review aggregated data from tracking logs and any annual workplace environment reports to identify and prioritize areas for improvement.

The protection of our frontline workforce is paramount in retaining individuals with valuable skills. This protection requires a change in industry mindset that acknowledges the shared responsibility among both employers and ultrasound operators.

This post was created from the AIUM Practice Principles for Work-Related Musculoskeletal Disorder, which was developed by the American Institute of Ultrasound in Medicine in collaboration and with the expressed support of the American College of Emergency Physicians (ACEP), American College of Obstetricians and Gynecologists (ACOG), American College of Radiology (ACR), American Registry for Diagnostic Medical Sonography (ARDMS), American Society of Echocardiography (ASE), Australasian Society for Ultrasound in Medicine (ASUM), Fetal Heart Society (FHS), Intersocietal Accreditation Commission (IAC), International Society of Ultrasound in Obstetrics and Gynecology (ISUOG), Joint Review Committee on Education in Cardiovascular Technology (JRC-CVT), Joint Review Committee on Education in Diagnostic Medical Sonography (JRC-DMS), Perinatal Quality Foundation (PQF), Society of Diagnostic Medical Sonography (SDMS), and Society for Maternal-Fetal Medicine (SMFM). The Practice Principle was developed to expand on the “Industry Standards for the Prevention of Work-Related Musculoskeletal Disorders in Sonography”13 to include safety practices for all health care professionals who utilize ultrasound.

References

  1. Evans K, Roll S, Baker J. Work-related musculoskeletal disorders (WRMSD) among registered diagnostic medical sonographers and vascular technologists. A representative sample. J Diagn Med Sonog 2009; 25:287– 299.
  2. Wareluk P, Jakubowski W. Evaluation of musculoskeletal symptoms among physicians performing ultrasound. J Ultrason 2017; 17:154– 159. https://doi.org/10.15557/JoU.2017.0023.
  3. Bowles D, Quinton A. The incidence and distribution of musculoskeletal disorders in final-year Australian sonography students on clinical placement. Sonography 2019; 6:157– 163. https://doi.org/10.1002/sono.12203.
  4. Gibbs V, Young P. A study of the experiences of participants following attendance at a workshop on methods to prevent or reduce work-related musculoskeletal disorders amongst sonographers. Radiography 2011; 17:223– 229. https://doi.org/10.1016/j.radi.2011.02.003.
  5. Baker JP, Coffin CT. The importance of an ergonomic workstation to practicing sonographers. J Ultrasound Med 2013; 32:1363– 1375. https://doi.org/10.7863/ultra.32.8.1363.
  6. Harrison G, Harris A. Work-related musculoskeletal disorders in ultrasound: can you reduce risk? Ultrasound 2015; 23:224– 230. https://doi.org/10.1177/1742271X15593575.
  7. Chari R, Chang CC, Sauter SL, et al. Expanding the paradigm of occupational safety and health: a new framework for worker well-being. J Occup Environ Med 2018; 60:589– 593.
  8. United States Department of Labor, Occupational Safety and Health Administration. Ergonomics website. https://www.osha.gov/ergonomics. Accessed November 12, 2021.
  9. United States Department of Labor, Occupational Safety and Health Administration. Solutions to control hazards website. https://www.osha.gov/ergonomics/control-hazards. Accessed November 12, 2021.
  10. United States Department of Labor, Occupational Safety and Health Administration. Identity problems website. https://www.osha.gov/ergonomics/identify-problems. Accessed November 12, 2021.
  11. Rousseau T, Mottet N, Mace G, Franceschini C, Sagot P. Practice guidelines for prevention of musculoskeletal disorders in obstetric sonography. J Ultrasound Med 2013; 32:157–164. https://doi.org/10.7863/jum.2013.32.1.157.
  12. BP Bernard (ed). Musculoskeletal Disorders and Workplace Factors; A Critical Review of Epidemiologic Evidence for Work-Related Musculoskeletal Disorders of the Neck, Upper Extremity, and Low Back. U.S. Department of Health and Human Services July; 1997 DHHS (NIOSH) Publication No. 97B141.
  13. Industry standards for the prevention of work related musculoskeletal disorders in sonography. J Diagn Med Sonogr 2017; 33:370–391.
  14. AIUM practice principles for work-related musculoskeletal disorder [published online ahead of print January 24, 2023]. J Ultrasound Med. https://doi.org/10.1002/jum.16124.

Musculotendinous Ultrasound Imaging Applications in Sports Medicine

There is a clearly established role of ultrasound imaging in traditional medical contexts to optimize patient assessment and subsequent care. These same applications have been carried over into sports medicine settings, especially with recent developments in ultrasound portability. Such technological advancements enable athletic trainers and other sports medicine clinicians to perform sideline assessments for athletes who sustain musculoskeletal injuries during sports.

Beyond diagnostic applications of ultrasound imaging, sports medicine clinicians and researchers have begun to adopt this tool as a creative means to assess musculotendinous structures in response to sport and exercise. Ultrasound imaging has advantages over other measurement techniques given that it is relatively inexpensive equipment, fairly easy to operate (especially if you know your anatomy!), and can be rapidly implemented into assessments. Ultrasound imaging also enables clinicians to perform more dynamic assessments with patients to understand functional movement patterns, and noninvasively examine deeper tissue structures. The real-time visual platform uniquely provides the opportunity to enhance patient-clinician dialogue and provide feedback to target key muscle groups during fundamental exercises.

Below, several exemplary studies that leverage ultrasound imaging in musculotendinous contexts are presented to convey the depth and breadth of innovation in the sports medicine field and highlight opportunities for future ultrasound implementation into practice.

Muscle Morphology

Ultrasound has been most frequently implemented in sports medicine research to conduct table-top assessments of musculotendinous structures. This measurement approach provides insights to clinicians on patients’ muscle and tendon changes in response to exercise (eg, weight- and height-adjusted size, fiber arrangement and quality). For example, researchers have been able to examine lower limb musculotendinous responses across long-distance running training.1,2 Beyond training adaptations, clinicians are also able to get some insights into structural tissue changes in the presence of current or future musculoskeletal injury. This has specifically been done to examine musculotendinous adaptations at the shoulder complex,3 foot complex,4 and lumbopelvic hip complex5 across a range of pathological populations. Preliminary work has begun to identify signals in tendon tissue quality that relate to future pain in running athletes.1 Such studies will continue to help inform rehabilitative and training interventions to improve muscle and tendon quality to move toward injury risk reduction in sports medicine.

Dynamic Muscle Function

In addition to the role of ultrasound imaging in more static imaging contexts, ultrasound has been implemented in sports medicine research in more functional contexts. Researchers have inventively started to use foam blocks with Velcro elastic belts to secure portable ultrasound probes on patients to visualize deep lumbopelvic hip muscles across a range of exercises and movements to assess the role of these muscles during fundamental movements (Figure).6 Through this approach, researchers have examined athletes’ transverse abdominis muscle thickness during an abdominal draw-in maneuver across patient positions to determine which activity elicited the most “bang for your buck” in muscle activity.7 Additionally, this measurement approach has been used to assess gluteal muscle function throughout treadmill walking. In these instances, ultrasound videos were obtained to quantify muscle activity throughout movement and identify activity dysfunction among patients with lower limb injuries.8,9 These examples emphasize the utility of ultrasound imaging to supplement typical sports medicine clinical assessments and underscore the opportunity for clinicians to implement ultrasound imaging in more dynamic assessments.

An athlete with ultrasound probes attached to her leg. A screen in the fore ground shows the ultrasound image.

Real-time Feedback

Ultrasound imaging demonstrates great promise as a rehabilitative feedback tool for patients who have difficulty recruiting specific muscle groups as a result of injury.10 The most robust use of ultrasound for feedback has been taking dynamic assessments of the lumbopelvic hip complex muscles a step further and using ultrasound to allow patients to visualize their muscles during abdominal contraction exercises. In this manner, clinicians have been able to show patients their muscle activity, and encourage activation of select muscles during rehabilitative exercises. This approach has been found to be more successful for patient neuromuscular education than other feedback approaches, such as verbal encouragement. The visual interface not only helps patients to see and understand muscle recruitment in real time but also helps clinicians to see when patients are able to activate proper stabilizing muscle groups as opposed to “cheating” on an exercise and using global movers to achieve a movement. While there is less available information on the use of ultrasound for feedback for targeting other muscle groups during rehabilitation, these studies highlight the opportunities for ultrasound imaging to maximize patient benefit during clinical interventions.

The Future of Ultrasound in Sports Medicine

Ultrasound imaging can clearly play a key role in sports medicine assessments and interventions. Continued research is necessary to broaden our understanding of musculotendinous changes in relation to sports injuries and rehabilitation, as current research is still scraping the surface of ultrasound opportunities in sports. Ultrasound assessments may complement other forms of athlete assessments and provide more in-depth insights into muscle and tendon function in relation to performance and injury. It is plausible that with continued technological advancements and the miniaturization of ultrasound units, clinicians may be able to use imaging during more sport-specific activities at higher velocities to unearth real-time musculotendinous changes in physical activity. The prospects of ultrasound are promising, and this tool may continue to revolutionize patient care in sports medicine clinics.

References

  1. Cushman DM, Petrin Z, Eby S, et al. Ultrasound evaluation of the patellar tendon and Achilles tendon and its association with future pain in distance runners. Phys Sportsmed. 2021; 49:410–419. doi:10.1080/00913847.2020.1847004.
  2. DeJong Lempke AF, Willwerth SB, Hunt DL, Meehan III WP, Whitney KE. Adolescent marathon training: prospective evaluation of musculotendinous changes during a 6-month endurance running program [published online ahead of print September 29, 2022]. J Ultrasound Med. doi:10.1002/jum.16105.
  3. Thomas SJ, Blubello A, Peterson A, et al. Master swimmers with shoulder pain and disability have altered functional and structural measures [published online ahead of print April 13, 2021]. J Athl Train. doi:10.4085/1062-6050-0067.21.
  4. Fraser JJ, Koldenhoven R, Hertel J. Ultrasound measures of intrinsic foot muscle size and activation following lateral ankle sprain and chronic ankle instability. J Sport Rehabil 2021; 30:1008–1018. doi:10.1123/jsr.2020-0372.
  5. Dieterich AV, Deshon L, Strauss GR, McKay J, Pickard CM. M-Mode ultrasound reveals earlier gluteus minimus activity in individuals with chronic hip pain during a step-down task. J Orthop Sports Phys Ther 2016; 46:277–285. doi:10.2519/jospt.2016.6132.
  6. DeJong AF, Mangum LC, Hertel J. Ultrasound imaging of the gluteal muscles during the Y-balance test in individuals with and without chronic ankle instability. J Athl Train 2019; 55:49–57. doi:10.4085/1062-6050-363-18.
  7. Mangum LC, Henderson K, Murray KP, Saliba SA. Ultrasound assessment of the transverse abdominis during functional movement: Transverse abdominis during movement. J Ultrasound Med 2018; 37:1225–1231. doi:10.1002/jum.14466.
  8. DeJong AF, Mangum LC, Hertel J. Gluteus medius activity during gait is altered in individuals with chronic ankle instability: An ultrasound imaging study. Gait Posture 2019; 71:7–13. doi:10.1016/j.gaitpost.2019.04.007.
  9. DeJong AF, Koldenhoven RM, Hart JM, Hertel J. Gluteus medius dysfunction in females with chronic ankle instability is consistent at different walking speeds. Clin Biomech (Bristol, Avon). 2020; 73:140–148. doi:10.1016/j.clinbiomech.2020.01.013.
  10. Valera-Calero JA, Fernández-de-Las-Peñas C, Varol U, Ortega-Santiago R, Gallego-Sendarrubias GM, Arias-Buría JL. Ultrasound imaging as a visual biofeedback tool in rehabilitation: An updated systematic review. Int J Environ Res Public Health. 2021; 18(14):7554. doi:10.3390/ijerph18147554.

Alexandra F. DeJong Lempke, PhD, ATC, is a clinical assistant professor of Applied Exercise Science, co-director of the Michigan Performance Research Lab, and a member of the Exercise & Sport Science Initiative within the U-M School of Kinesiology.

Interested in reading more about MSK ultrasound? Check out these posts from the Scan:

The Potential of Elastography in MSK Ultrasound

Elastography is a method of imaging that detects the compressibility or stiffness of tissues in the imaging field and then overlays a false-color map upon the greyscale image to indicate which tissues are hard/stiff versus soft/compressible. The science behind the technique is beyond the scope of a blog post, particularly as there are several methods by which elastography can be performed.  

In practical terms, elastography is useful in identifying lesions that are sonographically iso-dense compared to their surroundings. Such lesions, while they are therefore visually “iso-grey” (if you will tolerate a neologism), may not be iso-compressible despite their iso-density, and thus when their differential compressibility is identified by elastography it becomes possible to characterize a lesion whose greyscale appearance is not instructive. Among the most common current uses of elastography are the characterization of breast and liver lesions, and indeed the well-known Fibroscan device is, in essence, liver elastography.

There are several instances in the field of musculoskeletal (MSK)/rheumatologic ultrasound in which this technology is appealing, but more work is needed before widespread use will be advisable. I will mention only two of the most obvious examples here. 

Example One

The first example is in the interrogation of a symptomatic tendon or ligament. Such a structure, whose normal function involves incredible amounts of linear tension, when disrupted by trauma or disease, would be expected to lose integrity in the region of the insult and become softer/more compressible than normal in that area.

Traditionally, elastography is not used to measure tendons and ligaments despite the validity of the above statement. The reason for this is that the stiffness of tissue, when measured by elastography, can be expressed in terms of the speed at which a deformation (compression wave) in the tissue propagates, usually in meters per second (there are other units by which stiffness can be measured, but for simplicity’s sake, I will leave it at that).

In the classical case of breast and liver lesions, this is not an issue since the surrounding normal tissue is relatively soft and compressible, so the speed of the propagation of a compression wave is relatively slow. Thus, most elastography measurements top out at a propagation speed of about 10 meters per second, and most normal and abnormal breast/liver tissue will have stiffness values somewhat slower than this. Tendons and ligaments, on the other hand, are by nature very hard/noncompressible. Even in their “relaxed” state, these tissues are so bowstring-tight (relatively) that measuring a normal Achilles’ tendon, for example, will yield only a maxed-out value of “offscale hard” throughout the entire structure. 

It is tempting to say that one could simply recalibrate the machine to measure faster propagation speeds, but, unfortunately, we run into limitations of our current technology. It is simply not possible currently to measure velocities much faster than 10 m/s. 

While we await advancements in technology, the current workaround is to trust that a damaged region of tendon or ligament will be significantly softer, and thus transmit compression waves much more slowly. Therefore, we simply consider any propagation speed that falls out of “offscale” and into the measurable range to be an indicator of pathology.

Example Two

The second example of the potential rheumatologic utility of elastography is in the assessment of systemic sclerosis, commonly known as scleroderma. As the Greek name would suggest, this disease usually includes a characteristic hardening of the skin. The problem is that there is currently no reliable way to quantify skin stiffness. The existing gold standard is a semi-quantitative scoring of skin thickening performed by simple physical examination in which each of several predefined regions of the skin is palpated and assigned a value from 0 to 3. This results in an overall score known as the Modified Rodnan Skin Score (MRSS). Performing Rodnan scoring requires an experienced clinician, and since scleroderma is a rare disease, very few physicians have a large enough cohort in their practice to be able to consider themselves expert Rodnan scorers.

This leads to a host of problems, and one of the worst is that clinical trials in scleroderma (a devastating and potentially fatal disease for which no good treatment exists) are very difficult to conduct because one of the primary endpoints of any trial will be the degree of improvement found in this semi-quantitative and hard-to-perform examination, which is subject to severe inter-rater reliability problems.

When I first started as a rheumatology fellow, I agreed to help with a scleroderma clinical trial in the role of a blinded efficacy assessor. The sponsor brought a dozen or so of us to a hotel for training, and all morning long we cycled through a series of hotel meeting rooms, each containing a volunteer patient for us to score.

It was a disaster.

After lunch, the representative from the sponsor got up to the podium and told us to rip up our afternoon agendas—we were going back to the meeting rooms to examine the volunteers again in an effort to improve the scoring consensus.

Clearly, this situation screams for elastography. The objective measurement of skin stiffness is precisely the datum that is sorely needed. Sadly, our current technology again fails us, as present-day elastography has limitations in resolution and the skin by its anatomic location, will always be very nearly directly applied to the probe face, in a region outside the focal zone of the beam where the measurement physics work best. Further, one of the techniques for performing elastography is highly operator-dependent, because the compression waves being measured are generated by manually varying the pressure of the probe against the skin—definitely a skill that must be learned over time and one that opens the door once more to inter-rater variability.

Overall, elastography holds great promise for MSK/rheumatologic applications in the future, as described in the two examples above. For now, however, it’s currently a technology that is “not ready for prime time” in this field.

This post is intended as a companion to “What Rheumatologists Really Need for Ultrasound Is…”, which discusses advances in ultrasound technology that are sorely needed in the field of MSK ultrasound, and specifically in rheumatology.

Dr. Mandelin is an academic rheumatologist, registered in MSK ultrasound (RhMSUS) by the American College of Rheumatology and certified in MSK ultrasound (RMSK) by the Alliance for Physician Certification & Advancement. He currently serves the AIUM as secretary of the High-Frequency Clinical and Preclinical Imaging Community. Connect with him on Twitter @NU_Rheum_MSK_US.

Do More With Less: Ultrasound

Life is not always easy, sometimes you just have to manage with what you have. To work with limited resources is one of the skills you acquire once you are a primary care physician and particularly in Africa.

This is also true concerning point-of-care ultrasound (POCUS); it is possible to do more with less. If you really understand how it works, you can find new ways to use your tools to get the correct diagnosis.

Now, I want to share with you the case of a 53-year-old male patient whose major complaint was joint pains, particularly in the left wrist and knee. Upon physical examination, the joints were warm, swollen, and painful. I hypothesized that the diagnosis was a primary gout episode but in my health facility I don’t have a uric acid test that I would ordinarily use for confirmation of the diagnosis. I then performed a POCUS examination to confirm the diagnosis by looking for the double contour cartilage line, which is a sign of gout in joints due to uric acid deposit at the surface of bone cartilage. I didn’t have a linear high-frequency probe, so I used an endocavitary probe just as you can see in the pictures.

Ultrasound images of the knee showing the double contour sign indicative of gout.

POCUS can greatly increase healthcare in low-income countries. Usually, the healthcare gap between upper-income and low-income countries is huge but, with POCUS, the same technics can be applied to both, with the same results, if ultrasound devices are available.

However, the problem remains that there is a lack of healthcare professionals who are skilled enough to use it and teach others. The problem is no longer an absence of devices but is now due to an absence of knowledge of how to use them.

Fortunately, due to COVID-19 lockdowns, we know almost everything that can be taught online. Therefore, it is time for us to think about establishing a new way to teach, learn, and practice ultrasound. Many ultrasound societies, such as the AIUM, ISUOG, and EDE, have started to share free POCUS education on their websites. Free online courses should be encouraged since they will lead us to the democratization of ultrasound, particularly in low-resource settings.

Yannick Ndefo, MD, is a general practitioner at St Thomas hospital in Douala, Cameroon.

Interested in learning more? Check out the following posts from the Scan:

A Faster Recovery for Carpal Tunnel Release

Carpal tunnel syndrome (CTS) is a phenomenon that occurs due to impingement of the median nerve at the wrist. It usually presents as numbness, tingling, and/or pain in the hand involving the thumb, index, and middle fingers. It commonly starts as nighttime numbness and tingling that awakens the patient and it can progress to being painful throughout the day. As it worsens in severity, it can produce weakness of the hand and loss of dexterity as well as radicular pain up the arm proximally toward the shoulder. There are several risk factors including repetitive use of the hands, such as with manual labor jobs, as well as obesity and rheumatologic conditions.

CTS is the most common compression neuropathy affecting 1.8–3.6% of the general population and up to 7% of manual laborers in the United States. Over 500,000 carpal tunnel releases (CTRs) are performed annually in the United States for definitive treatment of severe or refractory CTS. Multiple CTR techniques exist with one common goal—cut (ie, release) the transverse carpal ligament (TCL). Releasing the TCL reduces pressure within the carpal tunnel and, thereby, resolves the compression of the median nerve allowing improvement in associated symptoms.

For many years, the gold standard technique was open CTR (OCTR). OCTR is safe and effective but involves a relatively large incision measuring ~2 inches at the base of the palm. The skin of the palm is thick and takes weeks to months to heal, so patients are often out of work and activity for up to 6–8 weeks post-OCTR. Therefore, the mini-open (m-OCTR) technique has become very popular because the incision size is reduced to ~1 inch. This reduces the size of the scar and healing times slightly, but patients are still restricted in activity for at least 4–6 weeks. Endoscopic CTR (ECTR) is an alternative option that involves two smaller ~0.5-inch incisions but has been associated with a higher risk of transient postoperative nerve symptoms and intraoperative neurovascular injury.

Advances in ultrasound (US) technology and training over the past 20 years have catapulted US-guided procedures into realms most never believed possible. Many current US machines provide extremely high-resolution imaging, allowing providers to confidently perform advanced US-guided procedures in a safe and effective manner. Amongst the procedures being successfully implemented into clinical practices across the country is CTR with US guidance.

CTR with US guidance involves making a very small, ~4 mm, incision in the distal forearm as opposed to incising the skin of the palm. The distal forearm skin is relatively thin and heals rapidly, enabling patients to return to full activity within 1 week. Prior to performing CTR with US guidance, the patient is scanned to ensure adequate visualization of major anatomic structures including the:

  1. Median nerve
  2. Palmar cutaneous branch
  3. Thenar motor branch
  4. 3rd common palmar digital nerve
  5. Osseous boundaries of the carpal tunnel (scaphoid, pisiform, trapezium, hook of hamate)
  6. Ulnar vessels within Guyon’s canal
  7. Transverse safe zone (TSZ) between the ulnar aspect of the median nerve and the radial aspect of the ulnar vessels or hook of the hamate, whichever lies more radial
  8. Distal transverse carpal ligament (TCL)
  9. Superficial palmar arterial arch (including Doppler)

If there are no contraindications to undergoing CTR with US guidance, then the procedure may be performed in either an outpatient clinic or an ambulatory surgical center.

CTR with US guidance is usually performed under local anesthetic. The patient is positioned supine with the arm abducted 90 degrees and the wrist slightly extended. Using a #15 blade scalpel, a ~4-mm incision is made at the level of the proximal wrist crease, penetrating the antebrachial fascia. The surgical device is then advanced under direct US visualization into the carpal tunnel, passing it between the hamate and median nerve within the TSZ, similar to ECTR. The distal tip is advanced such that the blade, when activated, will engage the distal TCL. The position of the device relative to the TSZ and surrounding neurovascular structures is confirmed with US. Using the lever handle, balloons are inflated to increase the TSZ. Next, the cutting knife is deployed and advanced in a retrograde fashion using the thumb slide. The TCL is cut distal to proximal using continuous US visualization. Following TCL transection, the device is removed and a sterile dressing is applied.

Following the procedure, Tylenol and/or NSAIDs is sufficient for pain control. No splinting, occupational therapy, or opioids are required. Patients may begin immediate wrist and hand motion and resume normal activities as tolerated. The only restriction is no lifting, pushing, or pulling greater than 10 pounds with the surgical hand for 1 week. This means that those with desk jobs may return to work the next day; manual laborers may return in 1 week.

Incision at level of proximal palmar crease immediately following the procedure.
Incision at the level of proximal palmar crease immediately following the procedure.

In summary, various CTR techniques exist. Although all techniques have good outcomes at 3 months and beyond, the immediate post-op recovery timeline favors the US-guidance technique. The early success of CTR with US guidance being implemented in clinics across the country is exciting for the field of interventional musculoskeletal ultrasound. The sky is the limit!

Brett Kindle, MD

Brett J. Kindle, MD, CAQSM, RMSK, is a sports medicine specialist at Andrews Institute for Orthopaedics and Sports Medicine, as well as the Medical Director of EXOS-Florida, the Associate Program Director for Andrews Institute Primary Care Sports Medicine Fellowship, and a Team Physician for Pensacola Blue Wahoos.

What Rheumatologists Really Need for Ultrasound Is…

After I graduated from a Rheumatology fellowship, I was invited to stay on as junior faculty and several years thereafter the ACR (that acronym stands for American College of Rheumatology – I have no idea why most people who are into ultrasound always think it means something else…) developed an educational initiative aimed at bringing MSK US to every Rheumatology training program in the USA.

The ACR began to invite about 20 training programs per year to nominate one faculty member whose journey through the Ultrasound School of North American Rheumatologists (USSONAR) would be subsidized by the College. The idea was that each USSONAR graduate would then start an MSK US training program at his or her home institution, and since there are only about 120 Rheumatology training programs in the USA, the whole process would only take about 6 years. The rate of adoption among training programs was of course not 100%, and there are several key barriers to the development of an ultrasound training program, but at our institution it worked.

I’ve been doing point-of-care MSK ultrasound ever since I completed USSONAR and passed my certification exams, and our institution now has a required half-day MSK ultrasound clinic in which every Rheumatology fellow spends 6 months as part of their required curriculum. While MSK US certification is not required for graduation or to sit for boards, I’m proud to say that so far three of our Rheumatology graduates have opted to sit for the exam and are now ultrasound certified.

The program has been in place for about 7 years now, so it seems a good time to begin reflecting on my impressions of how MSK US fits into a Rheumatology practice, and more importantly some of the ways in which the current off-the-shelf technology doesn’t fully meet our specialty’s needs.

Clearly, MSK US is a major boon to Rheumatology in terms of needle guidance. Our half-day ultrasound clinic has made it possible for us to stop referring hip injections out to Interventional Radiology or Anesthesia-Pain, and I’m hoping that we will soon be able to bring sacroiliac joint injections back in-house as well. Diagnostically, the most common reason a patient is referred to the ultrasound clinic is for disambiguation of the borderline / nebulous case—that patient who endorses symptoms that sound like active inflammation but whose physical exam is benign. Our most common diagnostic referral is to answer the question of whether or not subclinical synovitis is present in the small joints of the hands, and that leads us to the first instance of current MSK US technology being less than a seamless integration into clinical practice and more of a square peg being jammed into a round hole.

The soft tissues associated with the small joints of the hands are at very shallow depths, usually under 1 cm in most patients. My very first ultrasound machine was a SonoSite M-MSK, and you adjusted the depth with a pair of pushbuttons. The standard procedure (and I would teach the fellows exactly this) was to start up the machine and then just start tapping the “less depth” button over and over.

Image of a finger joint with a ruler indicating the small height of the joint  is less than 2 centimeters.

“Just keep tapping,” I would tell the fellow. “Tap it like you’re playing Space Invaders, and just keep hitting it until the machine starts beeping in protest because the minimum depth has been reached.”

Even at that minimum setting, most ultrasound machines still show a depth of about 2 cm. I often joke with the fellows that this setting would be wonderful if we were trying to look clear through the patient’s hand and figure out what material the cushion on the exam table was made of!

Astute readers will also realize that no matter what the depth on the machine is set to, this puts the target structure (again, usually at a depth of 0.5–1 cm) closer to the probe face than the optimal focal zone distance on many probes—we are giving ourselves a case of technological hyperopia.

A stand-off pad will help keep the tissue at a better focal distance, but these pads can be cumbersome and will make the learning curve for any fellow even steeper than it already is by virtue of obscuring the tactile input, which is integral to the hands-on nature of point-of-care sonography. Ultrasound doesn’t feel like a natural extension of the physical exam with a stand-off pad in the way.

The real solution here is to switch to ultra-high-frequency ultrasound, something in the 50–70 MHz range, where the depth bar at the edge of the monitor is labeled in millimeters instead of centimeters. For small joints, I think this has to be the future of MSK ultrasound. This is why I was interested in the AIUM’s Community on High Frequency Clinical and Preclinical Imaging, and ultimately volunteered to serve among its leadership. Sadly, these UHF machines are expensive and they are often purpose-built for ultra-high-frequency only, meaning that a top of the line Rheumatologic MSK US clinic would need to own two machines, one UHF and one standard.  

This won’t fly in most places.

One of the main reasons why the ACR’s vision for an MSK US curriculum in every Rheumatology training program has not been fully realized is the expense involved in acquiring even one machine.

When we are looking at the hands of that patient whose clinical presentation is ambiguous—whose symptoms don’t seem to match their physical exam and in whom occult synovitis is suspected—we are looking for three telltale sonographic signs of the ravages of inflammation: hypertrophy of the synovium, the presence of a joint effusion, and hyperemia from the irritated joint lining struggling to summon blood flow to meet its elevated metabolic demands. The first two are often lumped together under the umbrella of “grayscale findings,” and the hyperemia is of course measured by Doppler.

The second hurdle for MSK US in the field of Rheumatology, then, is that of Doppler sensitivity. We are trying to examine and even semi-quantify the blood flow in capillaries, using equipment designed to measure the jets from regurgitant heart valves. Power Doppler is helpful here, due to its independence from the angle of insonation, but again we end up playing every trick in the book (starting with turning the wall filter off completely, if the machine even allows it) trying to squeeze every iota of signal out of the noise.

I always start the hand exam with a calibration image, in which I capture the blood flow in the pulp of a fingertip. Sometimes, especially in the midst of Chicago winters, you can’t even tell the Doppler is on at all. Currently, there’s nothing to do in that situation other than to comment in the report that Doppler calibration failed and thus the sensitivity of the study for detecting active synovitis (the very thing for which the study was ordered) is significantly compromised.

Taken together, it would seem that perhaps what we really need is for manufacturers to go beyond a blanket “MSK” setting in their machines and offer a true “Rheum” optimization package.

Dr. Mandelin is an academic rheumatologist, registered in MSK ultrasound (RhMSUS) by the American College of Rheumatology and certified in MSK ultrasound (RMSK) by the Alliance for Physician Certification & Advancement. He currently serves the AIUM as secretary of the High Frequency Clinical and Preclinical Imaging Community.

Where do you think MSK ultrasound is headed? Rheumatologists, where else does the technology not quite work in terms of your practice? Comment below or join in the conversation on Twitter, where my handle is @NU_Rheum_MSK_US.

Interested in learning more from the Scan? Check out the following posts:

The Role of Musculoskeletal Ultrasound in Sports Injuries

Approximately 20% of the U.S. population engaged in sports or exercise on a daily basis from 2010–2019.1 As expected, exercise and sports-related injuries are common, not only in the elite athlete but also in the general population. These injuries frequently lead to sport participation absence (SPA) and often, contact with the health care system. Although history and physical examination are the primary tools of diagnosis, musculoskeletal ultrasound (MSK US) has become the “stethoscope” for evaluation of sports medicine patients.

Even though MSK US has been widely used in Canada and Europe for years, the dramatic utilization increase in the United States has only occurred over the last two decades.2, 3 Between 2003 and 2015, there was a 347% increase in total MSK US volume within the Medicare population.3 The growth in subspecialties such as physical medicine and rehabilitation, rheumatology, and sports medicine has outpaced the growth in radiology. This Point-of-Care Ultrasound (POCUS) by clinicians may help facilitate diagnosis, expedite treatment planning, and reduce patient wait time and number of visits by offering one-stop clinics. 

Cristy Nicole French, MD
Cristy Nicole French, MD

POCUS can be quite useful to evaluate sports injuries. Propelled by advances in technology, the advent of compact, portable, and more affordable ultrasound machines may facilitate prompt diagnosis of sports injuries on the field and in the training room. The real-time nature of ultrasound provides the opportunity to interact with the athlete and correlate symptoms with sonographic findings. Patients enjoy this opportunity to “share their story” and often provide critical information to the diagnostic puzzle. They also appreciate the immediate findings the physician may be able to provide at the time of imaging. In fact, most patients actually prefer ultrasound to MRI.4 Other unique advantages of MSK US for sports imaging are the ability to easily assess the contralateral side as a control and the capability for dynamic imaging. Ultrasound guidance can also improve accuracy in targeted percutaneous injection therapies.4 Sports clinicians often encounter a treatment gap for a substantial percentage of young, active patients with a strong desire to return to activity, yet for whom conservative measures have failed and surgery is not indicated. Fueled by media coverage of the treatment of high-profile professional athletes, the field of orthobiologics has exploded in recent years. Ultrasound can provide target localization during administration of a wide array of injectable agents (prolotherapy, autologous whole blood, and platelet-rich plasma) in addition to image-guided peritendinous corticosteroid injections, tendon needling or fenestration, and even percutaneous ultrasonic tenotomy (Tenex).

With the development of high-frequency transducers, MSK US has equal diagnostic accuracy to magnetic resonance imaging (MRI) for evaluation of many superficial tendon and ligament abnormalities. In the current era of cost containment, the utilization of MSK US as an alternative to other more expensive imaging modalities may represent an effective way to save healthcare dollars.5, 6 However, many issues related to accuracy, observer variability, and high-quality training need to be considered, aside from pure economics, to ensure that MSK US is ethically and adequately performed in the best interest of patient care.

As any of us who have picked up a transducer know, some of the most significant disadvantages of ultrasound are the relatively long learning curve and inherent operator dependence. These challenges are compounded in MSK US by the complex anatomy, pathology, and terminology not often included in general ultrasound education programs. Dedicated training and standardized technique can minimize these limitations. Many subspecialty residency and fellowship programs have recognized the necessity of standardized, high-quality training and have strategically designed curricula to become proficient in the core competencies of MSK US.

In recent years, quantitative ultrasound methods, such as shear-wave elastography (SWE) and contrast-enhanced ultrasound, have emerged as an adjunct tool to standard B-mode imaging in the evaluation of various structures throughout the body. In particular, SWE has seen an exponential increase in the number of musculoskeletal applications. Shear-wave elastography can assess tissue stiffness by applying a mechanical stress that generates shear waves, which then travel through the tissue at a speed proportional to its stiffness. By quantifying mechanical and elastic tissue properties, SWE may provide important information about pre-clinical injuries in musculoskeletal tissues as well as tissue healing after injury. Although SWE is FDA-approved on most ultrasound platforms, its use for clinical imaging in musculoskeletal ultrasound has lagged behind research due to lack of standardization in study protocols, techniques, and outcomes measures. Nonetheless, SWE has a promising role in the future of ultrasonography in sports medicine and may help practitioners to better estimate injury severity and individualize the retraining plan for the injured athlete.

References

  1. Hauret KG, Bedno S, Loringer K, Kao TC, Mallon T, Jones BH. Epidemiology of Exercise- and Sports-Related Injuries in a Population of Young, Physically Active Adults: A Survey of Military Servicemembers. Am J Sports Med. Nov 2015;43(11):2645-53. doi:10.1177/0363546515601990
  2. Sharpe RE, Nazarian LN, Parker L, Rao VM, Levin DC. Dramatically increased musculoskeletal ultrasound utilization from 2000 to 2009, especially by podiatrists in private offices. J Am Coll Radiol. Feb 2012;9(2):141-6. doi:10.1016/j.jacr.2011.09.008
  3. Kanesa-Thasan RM, Nazarian LN, Parker L, Rao VM, Levin DC. Comparative Trends in Utilization of MRI and Ultrasound to Evaluate Nonspine Joint Disease 2003 to 2015. J Am Coll Radiol. Mar 2018;15(3 Pt A):402-407. doi:10.1016/j.jacr.2017.10.015
  4. Nazarian LN. The top 10 reasons musculoskeletal sonography is an important complementary or alternative technique to MRI. AJR Am J Roentgenol. Jun 2008;190(6):1621-6. doi:10.2214/ajr.07.3385
  5. Parker L, Nazarian LN, Carrino JA, et al. Musculoskeletal imaging: medicare use, costs, and potential for cost substitution. J Am Coll Radiol. Mar 2008;5(3):182-8. doi:10.1016/j.jacr.2007.07.016
  6. Bureau NJ, Ziegler D. Economics of Musculoskeletal Ultrasound. Curr Radiol Rep. 2016;4:44. doi:10.1007/s40134-016-0169-5

Dr. Cristy French (Twitter: @cristy_french) is an Associate Professor in the Division of Musculoskeletal Radiology at Penn State Health Milton S. Hershey Medical Center. She is the Director of Musculoskeletal Ultrasound as well as the Musculoskeletal Fellowship Director.