Ultrasound Findings of Delayed-Onset Muscle Soreness

Assessment of the Performance of Ultrasonography for Detecting Myofascial Trigger Points

Needle electromyogram (EMG) research has suggested that endplate noise (EPN) is a characteristic of myofascial trigger points (MTrPs). Although several studies have observed MTrPs through ultrasonography, whether they are hyperechoic or hypoechoic in ultrasound images is still controversial. Therefore, this study determined the echogenicity of MTrP ultrasonography. In stage 1, the MTrP of rat masseter muscle was identified through palpation and marked. Needle EMG was performed to detect the presence of EPN. When EPN was detected, ultrasound scans and indwelling needles were used to identify the nodule with a different grayscale relative to that of its surrounding tissue, and the echogenicity of the identified MTrP was determined. In stage 2, these steps were reversed. An ultrasound scan was performed to detect the nodule at the marked site, and an EMG needle was inserted into the nodule to detect EPN. There were 178 recordings in each stage, obtained from 45 rats. The stage 1 results indicate that the MTrPs in ultrasound images were hypoechoic with a 100% sensitivity of assessment. In stage 2, the accuracy and precision of MTrP detection through ultrasonography were 89.9% and 89.2%, respectively. The results indicate that ultrasonography produces highly accurate and precise MTrP detection results.

Imaging of Muscle Injuries

Ultrasound (US) and MR imaging are the most common imaging modalities used to assess sports muscle injuries. The site of the muscle injury can be located at the peripheral aspect of the muscle (myofascial), within the muscle belly (musculotendinous), and with tendon involvement (intratendinous). Tears that affect the intramuscular tendon have a worse prognosis in terms of recovery time. US is an excellent method to evaluate muscle injuries, with high spatial and contrast resolution. MR imaging can be reserved for evaluation of professional athletes, surgical planning, differential diagnosis, and assessment of deep located and proximal muscle groups.

Non-Vascular Considerations When Interpreting Extremity Arterial and Venous Examinations

Peripheral arterial and venous examinations are performed regularly in vascular labs and interpreted by physicians of different specialities. Many vascular examinations have nonvascular pathology that is either inadvertently imaged by the sonographer or imaged with intent as it relates to patient's symptoms. It is prudent for every reader of vascular studies to be acquainted with the sonographic appearance of these non-vascular lesions to enable appropriate and optimal interpretation that has a direct bearing on patient's clinical care. Our review includes a discussion of the nonvascular pathologies like lymph nodes, soft tissue edema, soft tissue fluid collections, musculotendinous injuries, soft tissue masses, and joint and bursal pathologies that may be encountered during interpretation of vascular exams. The pictorial essay includes a discussion of their sonographic appearances and pitfalls in interpretation. Multiple illustrative examples and sonographic images of the non-vascular pathologies found during interpretation of vascular studies have been utilized to highlight their appearances.

Recommended Musculoskeletal and Sports Ultrasound Terminology: A Delphi-Based Consensus Statement

OBJECTIVES

The current lack of agreement regarding standardized terminology in musculoskeletal and sports ultrasound presents challenges in education, clinical practice, and research. This consensus was developed to provide a reference to improve clarity and consistency in communication.

METHODS

A multidisciplinary expert panel was convened consisting of 18 members representing multiple specialty societies identified as key stakeholders in musculoskeletal and sports ultrasound. A Delphi process was used to reach consensus which was defined as group level agreement >80%.

RESULTS

Content was organized into seven general topics including: 1) General Definitions, 2) Equipment and Transducer Manipulation, 3) Anatomic and Descriptive Terminology, 4) Pathology, 5) Procedural Terminology, 6) Image Labeling, and 7) Documentation. Terms and definitions which reached consensus agreement are presented herein.

CONCLUSIONS

The historic use of multiple similar terms in the absence of precise definitions has led to confusion when conveying information between colleagues, patients, and third-party payers. This multidisciplinary expert consensus addresses multiple areas of variability in diagnostic ultrasound imaging and ultrasound-guided procedures related to musculoskeletal and sports medicine.

Recommended musculoskeletal and sports ultrasound terminology: a Delphi-based consensus statement

The current lack of agreement regarding standardised terminology in musculoskeletal and sports ultrasound presents challenges in education, clinical practice and research. This consensus was developed to provide a reference to improve clarity and consistency in communication. A multidisciplinary expert panel was convened consisting of 18 members representing multiple specialty societies identified as key stakeholders in musculoskeletal and sports ultrasound. A Delphi process was used to reach consensus, which was defined as group level agreement of >80%. Content was organised into seven general topics including: (1) general definitions, (2) equipment and transducer manipulation, (3) anatomical and descriptive terminology, (4) pathology, (5) procedural terminology, (6) image labelling and (7) documentation. Terms and definitions which reached consensus agreement are presented herein. The historic use of multiple similar terms in the absence of precise definitions has led to confusion when conveying information between colleagues, patients and third-party payers. This multidisciplinary expert consensus addresses multiple areas of variability in diagnostic ultrasound imaging and ultrasound-guided procedures related to musculoskeletal and sports medicine.

Myotendinous pseudomasses: an imaging review

A mass or a tumor may not always be an underlying cause for a clinically apparent swelling. A wide range of myotendinous disorders can present as pseudomasses. These include muscle/myofascial hernia, tendon tears, benign hypertrophy, accessory muscles, tendon xanthomas, diffuse myositis, and exertional compartment syndromes. We have briefly reviewed these lesions highlighting their typical radiological findings and have also highlighted the role of different imaging modalities and the role of dynamic imaging. Although rare, radiologists should be aware of these entities to avoid mislabeling a pseudomass as a mass or malignancy and to detect the abnormality in not-so-apparent masses.

Muscle Imaging

Evaluation and characterization of skeletal muscle pathology is a frequently encountered indication for musculoskeletal imaging. Causes of muscle pathology are diverse and include traumatic, autoimmune, infectious, inflammatory, neurologic, and neoplastic. Each etiology while dramatically different in the pathophysiology may present with similar imaging features. An understanding of the subtle differences in imaging features between the pathologic conditions may serve to guide diagnosis and treatment in these often complex cases. In this section, we will discuss the various skeletal muscle pathologies and the imaging features associated with each.

Ultrasound Features of the Proximal Hamstring Muscle-Tendon-Bone Unit

The hamstring muscle complex is made by a group of posterior biarticular thigh muscles, originating at the ischial tuberosity, which extend the hip and flex the knee joint. Proximal hamstring injuries are frequent among athletes, commonly involving their long myotendinous junction during an eccentric contraction. In this pictorial essay, we describe the ultrasound technique to visualize the normal anatomy of the proximal hamstring muscle-tendon-bone complex and present ultrasound findings in patients with traumatic injuries and tendinopathies.