Dynamic contrast-enhanced ultrasound and elastography assess deltoid muscle integrity after reverse shoulder arthroplasty

Bone Density Changes at the Origin of the Deltoid Muscle following Reverse Shoulder Arthroplasty

Background: Reverse total shoulder arthroplasty (RSA) significantly impacts deltoid length, tension, and structure. Studies have extensively investigated various modifications in deltoid characteristics, such as perfusion, elasticity, caliber, histological changes, and strength post-RSA. However, to date, there is a notable absence of research evaluating changes in bone mineral density (BMD) at the deltoid muscle origin after the RSA procedure. Methods: A retrospective analysis of a consecutive series of RSAs performed between May 2011 and May 2022 was conducted. Inclusion criteria comprised primary RSAs with both preoperative and last follow-up shoulder CT scans and a minimum follow-up of 12 months. Trabecular attenuation measured in Hounsfield units (HU) was calculated using a rapid region-of-interest (ROI) method. BMD analysis involved segmenting three ROIs in both pre- and postoperative CT scans of each patient: the acromion, clavicle, and spine of the scapula. Results: A total of 44 RSAs in 43 patients, comprising 29 women and 14 men, were included in this study. The mean follow-up duration was 49 ± 22.64 months. Significant differences were observed between preoperative and postoperative HU values in all analyzed regions. Specifically, BMD increased in the acromion and spine, while it decreased in the clavicle (p-values 0.0019, <0.0001, and 0.0088, respectively). Conclusions: The modifications in shoulder biomechanics and, consequently, deltoid tension post-implantation result in discernible variations in bone quality within the analyzed regions. This study underscores the importance of thorough preoperative patient planning. By utilizing CT images routinely obtained before reverse shoulder replacement surgery, patients at high risk for fractures of the acromion, clavicle, and scapular spine can be identified.

Imaging in shoulder arthroplasty: Current applications and future perspectives

Shoulder arthroplasty has become a standard surgical procedure for treating a variety of complex shoulder disorders, including those with degenerative and traumatic aetiologies. The ever-improving success rates of shoulder arthroplasty could be attributed to advancements in endoprosthesis design, improvements in the biomechanics of endoprosthetic components, and improvements in surgical techniques. It improves patient outcomes and helps restore shoulder joint function and mobility. Imaging plays a vital role by enabling surgeons to plan arthroplasty procedures, help guide endoprosthesis placement, and monitor postoperative outcomes. In addition, imaging plays a role in assessing the residual bone stock and status of rotator cuff integrity and in correcting the placement of prosthetic components to restore shoulder mobility. CT-guided navigation aids surgeons by helping them choose appropriate components for implants and ensuring that implants are placed optimally during surgery. It can lead to better surgical results with reduced patient morbidity and a longer duration of prosthetic stability. After surgery, it is crucial to use imaging techniques to detect issues such as periprosthetic loosening, infections, or fractures to start effective management strategies to enhance patient recovery. This article aims to provide orthopaedic surgeons and radiologists with knowledge on the imaging methods used in shoulder arthroplasty and their role in presurgical planning, intraoperative guidance and postoperative assessment. In this study, we aimed to investigate the rationale behind utilising various types of shoulder replacements: total shoulder replacement (TSA), reverse total shoulder arthroplasty (RTSA), and hemiarthroplasty; methods, their respective advantages and limitations; and outcomes. Our objective is to comprehensively analyse the procedures mentioned above and highlight their unique features and benefits to facilitate a better understanding of these approaches. Additionally, we will discuss how these imaging techniques help identify issues such as loose components, fractures around the implant site, joint instability and infections.

Contrast-Enhanced Ultrasound-Assessed Supraspinatus Muscle Perfusion Indicates Better Tissue Vitality and Outcome After Supraspinatus Tendon Repair and Subacromial Decompression

OBJECTIVE

Supraspinatus tendon (SSP) tears are a frequent indication for shoulder surgery. Therapy options include physiotherapy, tendon repair and less invasive surgical options like subacromial decompression (SAD). The selection of the most appropriate treatment depends on the specific characteristics and needs of each patient subgroup. Typically, physically active patients are candidates for tendon repair, while a conservative approach is preferred for individuals with severe muscle degeneration or low physical demands. The goal of this study was to assess the impact of contrast-enhanced ultrasound (CEUS)-assessed SSP muscle perfusion on post-operative shoulder function and tendon healing in patients undergoing SSP repair or SAD, thereby enhancing personalized therapy for SSP tendon tears.

METHODS

Two cohorts of patients with SSP tendon tears were treated either by SAD or tendon repair. Pre-operative and 6-month post-operative SSP muscle perfusion was quantified using CEUS and investigated as a surrogate for tissue vitality. The magnetic resonance imaging-derived parameters fatty infiltration and tendon retraction and established shoulder function scores were assessed pre- and post-operatively.

RESULTS

Thirty-five SSP repair patients were compared with 20 SAD patients. Pre-operative perfusion was comparable in the SAD and SSP repair cohorts when a re-tear occurred (wash-in perfusion index = 103.8 ± 124.0 vs. 114.6 ± 155.0, p = 0.83), while being significantly higher among patients with an intact repair (103.8 ± 124 vs. 325.4 ± 388.6, p = 0.006). Below-median pre-operative muscle perfusion was associated with lower post-operative shoulder function (Constant score: 59 ± 28 vs. 78 ± 19, p = 0.012).

CONCLUSION

CEUS can visualize SSP muscle perfusion as a surrogate for tissue vitality and tendon healing, which is associated with better post-operative shoulder function.

Deltoid Muscle Tension Alterations Post Reverse Shoulder Arthroplasty: An Investigation Using Shear Wave Elastography

INTRODUCTION

This study aimed to evaluate the utility of shear wave elastography (SWE) in assessing changes in deltoid muscle properties following reverse shoulder arthroplasty (RSA).

METHODS

Our cohort consisted of 18 patients who underwent RSA due to various conditions, including osteoarthritis, cuff arthropathy, and irreducible proximal humeral fractures. Pre- and postoperative muscle elasticity and stiffness were measured using SWE and were compared with functional outcomes and radiological parameters.

RESULTS

Our results showed significant changes in deltoid muscle elasticity after RSA, particularly in the anterior and middle portions. However, these alterations were not correlated with postoperative functional outcomes or specific radiological parameters. The study also underscored the potential of SWE for future applications, including the preoperative assessment of deltoid function, postoperative monitoring, and intraoperative use for optimal component positioning during RSA.

CONCLUSION

Further research, involving larger, more homogeneous patient cohorts is needed to confirm these findings and to explore the potential influence of these changes on the biomechanical design of implants and prosthesis positioning in RSA.

Measuring Shear Wave Velocity in Adult Skeletal Muscle with Ultrasound 2-D Shear Wave Elastography: A Scoping Review

Ultrasound 2-D shear wave elastography (US 2D-SWE) is a non-invasive, cost-effective tool for quantifying tissue stiffness. Amidst growing interest in US 2D-SWE for musculoskeletal research, it has been recommended that shear wave velocity (SWV) should be reported instead of elastic moduli to avoid introducing unwanted error into the data. This scoping review examined the evolving use of US 2D-SWE to measure SWV in skeletal muscle and identified strengths and weaknesses to guide future research. We searched electronic databases and key review reference lists to identify articles published between January 2000 and May 2021. Two reviewers assessed the eligibility of records during title/abstract and full-text screening, and one reviewer extracted and coded the data. Sixty-six studies met the eligibility criteria, of which 58 were published in 2017 or later. We found a striking lack of consensus regarding the effects of age and sex on skeletal muscle SWV, and widely variable reliability values. Substantial differences in methodology between studies suggest a pressing need for developing standardized, validated scanning protocols. This scoping review illustrates the breadth of application for US 2D-SWE in musculoskeletal research, and the data synthesis exposed several notable inconsistencies and gaps in current literature that warrant consideration in future studies.

Update of Contrast-enhanced Ultrasound in Musculoskeletal Medicine: Clinical Perspectives - A Review

Contrast-enhanced ultrasound (CEUS) uses an intravascular contrast agent to enhance blood flow signals and assess microcirculation in different parts of the human body. Over the past decade, CEUS has become more widely applied in musculoskeletal (MSK) medicine, and the current review aims to systematically summarize current research on the application of CEUS in the MSK field, focusing on 67 articles published between January 2001 and June 2021 in online databases including PubMed, Scopus, and Embase. CEUS has been widely used for the clinical assessment of muscle microcirculation, tendinopathy, fracture nonunions, sports-related injuries, arthritis, peripheral nerves, and tumors, and can serve as an objective and quantitative evaluation tool for prognosis and outcome prediction. Optimal CEUS parameters and diagnostic cut off values for each disease category remain to be confirmed.

Functional outcome and CEUS-assessed deltoid muscle vitality after fracture-specific versus standard prosthetic design in reverse shoulder arthroplasty for trauma

Functional outcome after reverse-shoulder-arthroplasty (RSA) in proximal humerus fractures (PHF) depends on deltoid muscle integrity and successful reattachment of the tuberosities for best possible recovery of rotator-cuff function. In this monocentric, prospective, randomized, controlled trial we investigated whether a reverse-fracture-prosthesis (RFP) with a metaphyseal fenestrated stem achieved superior shoulder and muscle function compared to a common reverse-prosthesis (RP) design for patients with PHF. Our hypothesis was that patients with RFP may achieve a superior healing rate of the greater tuberosity (GT) compared to patients receiving RP, which translates to significantly higher clinical outcome and functional scores as well as differences in deltoid muscle microperfusion. Forty-four patients with PHF were randomized preoperatively to one of the prosthesis types in RSA between 2018 and 2020 (22 with RFP and 22 with RP) and prospectively assessed 6 months after surgery. We assessed osteointegration of the GT with radiographs 1 day and 6 months postoperatively and examined shoulder function and patient satisfaction by using established shoulder scores. A contrast-enhanced ultrasound (CEUS) examination of both shoulders was performed to quantify intramuscular blood flow and evaluate vitality of the deltoid muscle. None of the functional and psychosocial scores or radiographs and ultrasound examinations showed significant differences between the RSA designs. The constant-Murley score (p = 0.384) and active anterior-elevation-abduction, and external rotation were comparable between the RFP and RP group. Similar healing rates of the GT were observed (p = 0.655). CEUS-assessed deltoid microperfusion revealed equivalent muscle vitality for both groups (p = 0.312). Level of evidence: Level II; Randomized Controlled Trial; Treatment Study. Clinical significance: The radiographic evaluation for the investigation of the GT healing rate indicates that the proclaimed benefits of the fracture prosthesis with fenestration design might not be as great as expected.

CEUS-assessed supraspinatus muscle perfusion improves after tendon repair and predicts anatomical and functional outcome: A 1-year prospective pilot study

Rotator cuff tear including SSP (Supraspinatus) tendon tears are a very common and often painful condition with several therapeutic options such as tendon repair. Reflected by the high retear rates, the preoperative selection of patients suitable for surgery or conservative treatment, which often yields comparable results, remains difficult. Using contrast-enhanced ultrasound (CEUS), it is possible to quantify the SSP muscle perfusion as a surrogate parameter for its vitality and healing capabilities. In this study, we enrolled 20 patients who underwent an SSP repair for a preoperative and two postoperative (6 months and 1 year) clinical and sonographic exams including CEUS. Along with functional improvement (p < 0.001, Constant score), we found a significant increase in CEUS-assessed muscle perfusion after tendon repair (p < 0.001). Furthermore, weak preoperative muscle perfusion was associated with a higher risk of a retear (χ²  = 0.045) and a moderate trend toward lower postoperative shoulder function that did not reach significance (r = 0.435; p = 0.055, DASH score). If confirmed in larger studies, CEUS might be a valuable additional diagnostic method for a precise selection of patients who most likely profit from a tendon repair and those who can be treated conservatively with an equally good outcome.

New perspectives for investigating muscular perfusion response after dietary supplement intake: an exploratory, randomized, double-blind, placebo-controlled crossover trial in healthy young athletes using contrast-enhanced ultrasound (CEUS)

Background

Various dietary supplements have been reported to enhance muscular perfusion in athletes practicing resistance training, especially through modulation of nitric oxide signaling.

Objectives

The aim of this study was therefore to investigate selected ‘NO-boosting’ supplements in a real-life setting i) to generate novel hypotheses and perfusion estimates for power calculation in view of a definitive trial and ii) to assess the feasibility of the study design with particular focus on the use of contrast-enhanced ultrasound (CEUS) for perfusion quantification.

Methods

Thirty young male athletes (24 ± 4 years) regularly practicing resistance training were enrolled in this three-arm, placebo(PL)-controlled crossover trial with ingestion of two commercially available supplements: an amino acid combination (AA) (containing 3 g of L-arginine-hydrochloride and 8 g of L-citrulline-malate) and 300 mg of a specific green tea extract (GTE). After intake, CEUS examinations of the dominant biceps brachii muscle were performed under resting conditions and following standardized resistance exercising. Quantitative parameters of biceps perfusion (peak enhancement, PE; wash-in perfusion index, WiPI) and caliber were derived from corresponding CEUS video files. Additionally, subjective muscle pump was determined after exercise.

Results

For PE, WiPI, and biceps caliber, the standard deviation (SD) of the within-subject differences between PL, AA, and GTE was determined, thereby allowing future sample size calculations. No significant differences between PL, AA, and GTE were observed for biceps perfusion, caliber, or muscle pump. When comparing resting with post-exercise measurements, the increase in biceps perfusion significantly correlated with the caliber increase (PE: r = 0.266, p = 0.0113; WiPI: r = 0.269, p = 0.0105). Similarly, the biceps perfusion correlated with muscle pump in the post-exercise conditions (PE: r = 0.354, p = 0.0006; WiPI: r = 0.350, p = 0.0007). A high participant adherence was achieved, and the acquisition of good quality CEUS video files was feasible. No adverse events occurred.

Conclusion

Based on our novel examination protocol, CEUS seems to be feasible following higher-load resistance exercising and may be used as a new method for high-resolution perfusion quantification to investigate the effects of pre-exercise dietary supplementation on muscle perfusion and related muscle size dynamics.

Quantitative Analysis of Contrast-Enhanced Ultrasound That Can Be Used to Evaluate Angiogenesis during Patellar Tendon Healing in Rats

Objective

To investigate the efficacy of contrast-enhanced ultrasound (CEUS) in quantitatively evaluating angiogenesis during patellar tendon healing in rats.

Methods

A total of 40 Sprague-Dawley rats were used in this study. The patellar tendons of 30 rats (60 limbs) that underwent incision and suture were treated as the operation group and monitored after 7, 14, and 28 days. The normal patellar tendons of 10 rats (20 limbs) were treated as the control group and monitored on day 0. The ultrasound examination was used to evaluate the structure and blood perfusion of the patellar tendon. Immunohistochemistry was used to assess angiogenesis, and the biomechanical test was used to verify functional recovery of the patellar tendon.

Results

The tendons in the operation group were significantly thickened compared with those in the control group (p < 0.01). The peak intensity (PI) in CEUS of the tendons showed a clear difference at each time point after the surgery (p < 0.01). PI increased in the operation group with a maximum on day 7, and then gradually decreased until day 28 when PI was close to the basic intensity (BI) in the control group (p > 0.05). It was consistent with the change of the CD31-positive staining areas representing angiogenesis of the injured patellar tendons. The PI was positively correlated with the CD31-positive staining area fraction (R = 0.849, p < 0.001). The failure load and tensile strength of the repaired patellar tendons in the operation group increased over time. The PI showed negative correlations with the failure load (R = -0.787, p < 0.001) and tensile strength (R = -0.714, p < 0.001).

Conclusion

The PI in CEUS could quantitatively reflect the time-dependent change in the blood supply of the healing site, and the PI correlated with histologic and biomechanical properties of the healing tendon. Quantitative analysis of contrast-enhanced ultrasound could be a useful method to evaluate angiogenesis in healing tendons.

Effects of neuromuscular electrical muscle stimulation on the deltoid for shoulder function restoration after reverse total shoulder arthroplasty in the early recovery period: a prospective randomized study

INTRODUCTION

Neuromuscular electrical stimulation (NMES) is a treatment modality that has been used to accelerate the rehabilitation of patients with neurological damage. However, it is unclear whether NMES of the deltoid can lead to the early restoration of shoulder function after reverse total shoulder arthroplasty (RSA).

MATERIALS AND METHODS

In this prospective and randomized study, 88 patients who underwent RSA with the same prosthesis design for cuff tear arthropathy or irreparable rotator cuff tear were assessed. The patients were divided into two groups (NMES group and non-NMES group, 44 patients each). For the NMES group, two pads of the NMES device were placed over the middle and posterior deltoid area, and NMES was maintained for 1 month after surgery. Shoulder functional outcomes and deltoid thickness were compared at 3, 6, and 12 months postoperatively. Shoulder functional outcomes were assessed based on the visual analog scale (VAS) for pain, American Shoulder and Elbow Surgeons (ASES), and Constant scores and the range of motion (ROM) and power of the affected shoulder. The thickness of the anterior, middle, and posterior deltoid was measured by ultrasonography.

RESULTS

A total of 76 patients (NMES group, 33 patients; non-NMES group, 43 patients) were enrolled in the final analysis. The preoperative demographics and status of the remaining rotator cuff of both groups were not significantly different. At postoperative 3 months, the ROM and power of external rotation of the NMES group were significantly greater than those of the non-NMES group (ROM, 36° ± 14° vs. 29° ± 12°; P = .003; power, 4.8 kg ± 1.8 kg vs. 3.8 kg ± 1.0 kg; P < .002). The ROM of external rotation of the NMES group at postoperative 6 months was also greater than that of the non-NMES group (41° ± 12° vs. 34° ± 11°; P = .013). However, there was no significant difference in the VAS, ASES, and Constant scores at all follow-up points despite gradual improvements until 1 year postoperatively. Serial measurements of the thickness of the anterior, middle, and posterior deltoid of both groups did not show significant differences.

CONCLUSIONS

Postoperative NMES of the deltoid after RSA contributed to significantly faster ROM restoration and considerable improvement in the power of external rotation. Therefore, NMES following RSA could lead to the early restoration of external rotation and recovery of deltoid function.

Ultrasound of the symptomatic shoulder arthroplasty: Spectrum and prevalence of periarticular soft tissue pathology

PURPOSE

To describe our experience using ultrasound (US) to evaluate postoperative complications in the presence of in situ shoulder arthroplasty.

METHODS

Review of patients who underwent US evaluation following total shoulder arthroplasty (TSA), reverse total shoulder arthroplasty (RTSA) or hemiarthroplasty from 2007 to 2020. All studies were reviewed independently by two musculoskeletal radiologists to assess for joint effusion, periarticular collection, and characterization of associated rotator cuff tears. Tendon tears were assessed with respect to (1) thickness: low grade (<50% thickness), high grade (>50% thickness), full thickness; (2) morphology (focal vs. diffuse) and location (insertion vs. critical zone). Inter-reader agreements were determined using Cohen's kappa test.

RESULTS

Ninety-seven studies were performed in 72 patients following TSA, RTSA, or hemiarthroplasty. Thirty-seven exams were solely for diagnostic purposes, and 59 were for guiding joint or periarticular collection aspiration. Twenty-eight studies assessed the cuff tendons post TSA. The mean time between surgery and US examination was 29.2 months. Complete or high-grade tears were identified in 8/28 (28.6%) diagnostic exams. The most commonly torn tendon among TSA patients was the subscapularis, with 13/28 (46.4%) demonstrating at least partial tearing. Inter-reader agreement was excellent for presence of effusion (k = 0.79, p < .001) and periarticular collection (k = 0.87, p < .001), and excellent agreement for presence of subscapularis tear (k = 0.78, p < .001), with fair agreement for assessment of supraspinatus (k = 0.66, p < .001) and infraspinatus (k = 0.60, p < .001) tears.

CONCLUSION

The most commonly torn tendon following anatomic TSA identified by US was the subscapularis, which was torn or deficient in 46.4% of cases. The majority of studies were performed for the guidance of percutaneous aspiration.

Contrast-enhanced ultrasound for musculoskeletal indications in children

The increasing use of contrast-enhanced ultrasound (CEUS) has opened exciting new frontiers for musculoskeletal applications in adults and children. The most common musculoskeletal-related CEUS applications in adults are for detecting inflammatory joint diseases, imaging skeletal muscles and tendon perfusion, imaging postoperative viability of osseous and osseocutaneous tissue flaps, and evaluating the malignant potential of soft-tissue masses. Pediatric musculoskeletal-related CEUS has been applied for imaging juvenile idiopathic arthritis and Legg-Calvé-Perthes disease and for evaluating femoral head perfusion following surgical hip reduction in children with developmental hip dysplasia. CEUS can improve visualization of the capillary network in superficial and deep tissues and also in states of slow- or low-volume blood flow. In addition, measurements of blood flow imaging parameters performed by quantitative CEUS are valuable when monitoring the outcome of treatment interventions. In this review article we present current experience regarding a wide range of CEUS applications in musculoskeletal conditions in adults and children, with emphasis on the latter, and discuss imaging techniques and CEUS findings in musculoskeletal applications.

The effect of glenoid lateralization and glenosphere size in reverse shoulder arthroplasty on deltoid load: A biomechanical cadaveric study

Purpose

Use of a relatively larger glenosphere with some larger overhang helps to minimize posterior impingement and some degree of glenoid lateralization is also beneficial in reverse shoulder arthroplasty (RSA). The optimal amounts of inferior overhang and lateralization are not agreed upon. The purpose of this in-vitro biomechanical study is to analyze the effect of glenosphere size and glenoid lateralization on deltoid load, focusing on differences in its three distinct heads.

Methods

Reverse shoulder arthroplasty (DeltaXtend, Fa. Depuy/Synthes) was performed on six cadaveric specimens. The load on each head of the deltoid muscle (spinalis, acromialis, and clavicularis) was measured indirectly by transferring deformation (μm/m) via strain gauges (Fa. Vishay) with stepwise lateralization: +0 mm (subgroup I), +5 mm (subgroup II), +10 mm (subgroup III). Each scenario was done with a 38 mm (group A) and a 42 mm (group B) glenosphere.

Results

In group A as well in group B, the mean measured deformation in the respective titanium omega increased with lateralization in the clavicular (AI: 119.6 μm/m, AIII: 307.3 μm/m; BI: 173.3 μm/m, BIII: 358.5 μm/m), in the spinal (AI: 85.3 μm/m, AIII: 188.5 μm/m; BI: 138.8 μm/m, BIII 261.2 μm/m) and in the acromial head (AI: 340.5 μm/μ; AIII: 454.2 μm/m; BI: 388.5 μm/m, BIII: 538.8 μm/m). A significant difference between the subgroups in the spinal (p = .048) and clavicular heads (p = .028) was found. The use of a 42 mm glenosphere increased significantly the load in each segment.

Conclusion

Lateralization and glenosphere size increased significantly deltoid muscle loading, especially in the clavicular head. According to these in-vitro data, the high variability in the amount of lateralization influences the soft-tissue balance in reverse shoulder arthroplasty.

Level of evidence

Basic science study.

Posttraumatic Perfusion Analysis of Quadriceps, Patellar, and Achilles Tendon Regeneration With Dynamic Contrast-Enhanced Ultrasound and Dynamic Contrast-Enhanced Magnetic Resonance Imaging: Preliminary Results

OBJECTIVES

The healing process of tendons after surgical treatment of tendon ruptures mainly depends on the perfusion of the tendon and its surrounding tissue. Dynamic contrast-enhanced ultrasound (DCE-US) and dynamic contrast-enhanced MRI (DCE-MRI) can provide additional information about the local microperfusion. In this pilot study, the feasibility of these techniques to assess the vascularization during tendon regeneration was evaluated.

METHODS

Between 2013 and 2015, 23 patients with surgical treatment of traumatic rupture of quadriceps, patellar, and Achilles tendons were involved. All patients received clinical follow-up examinations at 6, 12, and at least 52 weeks postoperatively. Dynamic contrast-enhanced US and DCE-MRI examinations were performed 6 and 12 weeks postoperatively. Dynamic contrast-enhanced US perfusion was quantified by the parameters peak enhancement, wash-in area under the curve, rise time, and initial area under the curve. Correlations between these parameters were examined via the Spearman rank correlation. The clinical and functional outcomes were assessed via the Lysholm Knee Score and Knee and Osteoarthritis Outcome Score at 12 and 52 weeks postoperatively.

RESULTS

Fourteen patients with quadriceps (n = 8), patellar (n = 4) and Achilles (n = 2) tendon ruptures with complete follow-up were available. The microperfusion could be successful assessed. We could detect a strong correlation of DCE-US (peak enhancement) parameters with DCE-MRI (initial area under the curve) parameters after 6 and 12 weeks.

CONCLUSIONS

In this pilot study, DCE-US was able to visualize the microperfusion of healing tendons with a strong correlation with DCE-MRI. Our initial results are in favor of DCE-US as a potential quantitative imaging tool for evaluating the vascularization in tendon regeneration as a complementary method.

Analysis of Three-Dimensional Ultrasound in Diagnosis of Shoulder and Neck Inflammation and Surrounding Tissue Lesions

Ultrasound imaging technology can not only show neck tear the degree and extent of disease, to help make the correct diagnosis, can also be used to assess shoulder neck inflammation after surgery to repair a shoulder muscle neck tissue integrity and healing. Ultrasound imaging with high-resolution, real-time operation, low cost, etc. gradually become shoulder neck inflammatory disease preferred imaging modality. The sensitivity and specificity for three-dimensional ultrasound imaging of shoulder neck inflammation were 78% and 93% in this study. The full-thickness inflammation sensitivity and specificity were 50% and 95%. The sensitivity and specificity of inflammation were 57% and 87%, respectively. This study shows that the diagnostic accuracy of 3D ultrasound imaging in shoulder and neck inflammation and surrounding tissue lesions is close to that of MRI. Three-dimensional appearance of new technologies such as ultrasound imaging will further improve ultrasound imaging techniques in shoulder neck inflammation application in the diagnosis and treatment assessment.

Evaluation of Bone Healing Using Contrast-Enhanced Ultrasonography in Non-Operative Treatment of Tibial Fracture in a Puppy Dog

Simple Summary

This report describes the clinical presentation of a tibial fracture in a young dog. treated with a conservative approach and subjected to X-ray, B-mode, Color Doppler and contrast-enhanced ultrasound (CEUS) examinations during the bone healing, in order to assess hemodynamic changes during fracture healing. This report showed the application of CEUS in controlling the fracture healing process.

Abstract

A 10-month-old mixed-breed male dog was presented with an oblique tibial fracture. The dog was treated with a Robert Jones-like bandage as a conservative approach, and was subjected to X-ray, B-mode, Color Doppler and contrast-enhanced ultrasound (CEUS) examinations during the fracture healing, in order to assess bone hemodynamic changes. B-mode, Power Doppler and CEUS examinations of the fracture gap were performed at 7, 20, 35, and 50 days post-trauma. Quantitative analysis of CEUS and perfusion parameters were obtained. On CEUS, a steep incline in signal numbers was visible in fracture gap at 7 days with peaks at 35 days, after which the vascularization decreases gradually over the next days. In this study, CEUS provided important information on the early stages of the callus formation and on the healing of neighboring tissues, allowing recognition of a correct bone healing. Moreover, the number of vascular signals on CEUS was greater than that on Doppler images on the same day. This report showed the application of CEUS in controlling the fracture healing process. CEUS could be a method of monitoring the remedial processes, assessing the tibial fracture perfusion characterized by low-velocity, small-volume blood flows.

Reversed shoulder arthroplasty leads to significant histological changes of the deltoid muscle: a prospective intervention trial

INTRODUCTION

Reverse shoulder arthroplasty (RSA) shows promising short- and mid-term results in cuff tear arthropathy. However, functional impairments are described in long-term findings. Micromorphological changes in the periarticular musculature could be in part responsible for this, but have not yet been analysed. Thus, histological changes of the deltoid muscle and their association to the functional outcome were evaluated in this study.

MATERIAL AND METHODS

A total of 15 patients treated with RSA were included in this prospective study. Functional outcome was assessed using the Constant Score (CS) and the DASH (disabilities of the arm, shoulder and hand) Score before RSA and after a mean follow-up of 12 months. Deltoid muscle biopsies were harvested intraoperatively and 12 months postoperatively. Mean deltoid muscle fibre area (MMFA) was calculated histologically after haematoxylin-eosin staining.

RESULTS

Postoperative shoulder function significantly improved within 12 months (CS: Δ 37.4 ± 22.6, p = 0.001; DASH: Δ 27.1 ± 29.1, p = 0.006). The MMFA significantly decreased (p = 0.02), comparing the results from the intraoperative biopsy (MMFA: 8435.8 µm², SD ± 5995.9 µm²) to the 12 months biopsy (MMFA: 5792. µm², SD ± 3223.6 µm²). No correlation could be found between the functional score results and MMFA.

CONCLUSION

Signs of deltoid muscle changes in terms of a reduced MMFA can be detected 1 year after RSA and thus already a long time before long-term functional impairments become apparent. Further studies with larger patient series and longer follow-up periods as well as extended histological assessments and simultaneous radiological examinations are required.

Contrast-enhanced ultrasound for determining muscular perfusion after oral intake of L-citrulline, L-arginine, and galloylated epicatechines: A study protocol

INTRODUCTION

The market for dietary supplements in the sports sector has been growing rapidly for several years, though there is still lacking evidence regarding their claimed benefits. One group is that of nitric oxide increasing supplements, so-called "NO-boosters," which are claimed to improve the supply of oxygen and nutrients to the muscle by enhancing vasodilation.The aim of this study was to investigate 3 of these supplements in healthy male athletes for their muscle perfusion-enhancing potential using contrast-enhanced ultrasound (CEUS).

METHODS

This placebo-controlled, double-blind, randomized cross-over trial will be carried out at the Center for Orthopedics, Trauma Surgery and Spinal Cord Injury of the University Hospital Heidelberg. Three commercial NO enhancing products including 300 mg of the specific green tea extract VASO6 and a combination of 8 g L-citrulline malate and 3 g L-arginine hydrochloride will be examined for their potential to increase muscular perfusion in 30-male athletes between 18 and 40 years and will be compared with a placebo. On each of the 3 appointments CEUS of the dominant biceps muscle will be performed at rest and after a standardized resistance training. Every athlete receives each of the 3 supplements once after a wash-out period of at least 1 week. Perfusion will be quantified via VueBox quantification software. The results of CEUS perfusion measurements will be compared intra- and interindividually and correlated with clinical parameters.

DISCUSSION

The results of this study may help to establish CEUS as a suitable imaging modality for the evaluation of potentially vasodilatory drugs in the field of sports. Other supplements could also be evaluated in this way to verify the content of their advertising claims.

TRIAL REGISTRATION

German Clinical Trials Register (DRKS), ID: DRKS00016972, registered on 25.03.2019.

The Relationship of Ultrasound Measurements of Muscle Deformation With Torque and Electromyography During Isometric Contractions of the Cervical Extensor Muscles

OBJECTIVES

Speckle tracking analysis (STA) of ultrasound (US) images quantifies the longitudinal deformation of a region of muscle tissue to provide a mechanical measure of muscle activity. As the validity and reliability of this method has not yet been adequately assessed, the aim of this study was to determine the validity and reliability of STA in the dorsal neck muscles during isometric neck extension contractions.

METHODS

Twenty volunteers performed 3 repetitions of isometric neck extension in a dynamometer at 10%, 20%, 40%, 60%, and 80% of maximal voluntary torque while US and surface electromyography (EMG) data were recorded. Speckle tracking analysis was then used to calculate measurements of muscle deformation. The relationship among torque, muscle deformation (separate for each muscle and summed), and EMG was evaluated using linear regressions and Spearman's correlation coefficients. The reliability of EMG and muscle deformation was determined using intraclass correlation coefficients (ICCs).

RESULTS

Muscle deformation in 4 of the 5 muscles when examined separately and collectively was significantly related to torque (P < .05); however, the relationship was weak (r² = 0.03-0.18). In contrast, a strong linear relationship was observed between torque and EMG (P < .001, r² = 0.83). Poor to moderate reliability of muscle deformation measures (ICC: 0.02-0.69) was found compared with EMG, which was highly reliable (ICC: 0.67-0.90).

CONCLUSION

These results suggest that the validity of US STA measurements for isometric contractions of the dorsal neck muscles is questionable. Further investigation into this method is required before it can be used as a tool to measure muscle activity.

Preoperative deltoid assessment by contrast-enhanced ultrasound (CEUS) as predictor for shoulder function after reverse shoulder arthroplasty: a prospective pilot study

INTRODUCTION

Although the deltoid represents the main motor muscle after reverse shoulder arthroplasty (RSA), its standardized preoperative assessment regarding morphology and function is still not established. Its clinical relevance and interactions with major biomechanical parameters like the medialization of the center of rotation (COR) regarding shoulder function after RSA are yet unknown. We evaluated contrast-enhanced ultrasound (CEUS) of the deltoid as possible surrogate marker for individual deltoid properties of patients receiving an RSA, and its predictive value for postoperative shoulder function.

MATERIALS AND METHODS

35 patients were prospectively assessed. Before and 6 months after RSA, dynamic deltoid perfusion, caliber and a combination of both (PE*caliber, named DeltoidEfficacy) was quantified by CEUS. Changes of deltoid properties and the predictive value of preoperative CEUS-based deltoid properties for shoulder function after RSA were assessed. To analyze interrelating effects with deltoid properties, COR-medialization and deltoid lengthening were quantified.

RESULTS

Deltoid caliber and perfusion significantly increased after RSA (p = 0.0004/p = 0.002). Preoperative deltoid caliber, perfusion and the combined value DeltoidEfficacy significantly correlated with shoulder function after RSA within the whole study cohort (caliber: r = 0.445, p = 0.009; perfusion: r = 0.593, p = 0.001; DeltoidEfficacy: r = 0.66; p = 0.0002). The predictive value of DeltoidEfficacy for shoulder function after RSA varied among patient subgroups: Multivariate regression analysis revealed the strongest prediction in patients with either very high or very low deltoid properties (Beta = 0.872, r = 0.84, p = 0.0004), independent from COR-medialization or deltoid lengthening. Contrary, in patients with intermediate deltoid properties, COR-medialization revealed the strongest predictive value for shoulder function after RSA (Beta = 0.660, r = 0.597; p = 0.024).

CONCLUSION

Deltoid CEUS seems to allow an assessment of individual deltoid properties and deltoid adaptations after RSA. Deltoid CEUS seems to predict shoulder function after RSA and might support an identification of patients requiring special attention regarding COR positioning.

Contrast-Enhanced Ultrasound for Musculoskeletal Applications: A World Federation for Ultrasound in Medicine and Biology Position Paper

This World Federation for Ultrasound in Medicine and Biology position paper reviews the diagnostic potential of ultrasound contrast agents for clinical decision-making and provides general advice for optimal contrast-enhanced ultrasound performance in musculoskeletal issues. In this domain, contrast-enhanced ultrasound performance has increasingly been investigated with promising results, but still lacks everyday clinical application and standardized techniques; therefore, experts summarized current knowledge according to published evidence and best personal experience. The goal was to intensify and standardize the use and administration of ultrasound contrast agents to facilitate correct diagnoses and ultimately to improve the management and outcomes of patients.

Contrast-Enhanced Ultrasound (CEUS) as Predictor for Early Retear and Functional Outcome After Supraspinatus Tendon Repair

Supraspinatus (SSP) tendon tears represent a common indication for shoulder surgery. Yet, prediction of postoperative function and tendon retear remains challenging and primarily relies on morphologic magnetic resonance imaging (MRI)-based parameters, supported by patients' demographic data like age, gender, and comorbidities. Considering continuously high retear rates, especially in patients with larger tears and negative prognostic factors, improved outcome prediction could be of high clinical value. Contrast-enhanced ultrasound (CEUS) enables an assessment of dynamic perfusion of the SSP muscle. As a potential surrogate for muscle vitality, CEUS might reflect functional properties of the SSP and support improved outcome prediction after tendon repair. Fifty patients with isolated SSP tendon tears were prospectively enrolled. Preoperatively, SSP muscle perfusion was quantified by CEUS and conventional morphologic parameters like tear size, fatty infiltration, and tendon retraction were assessed by MRI. At six months follow-up, shoulder function, tendon integrity, and muscle perfusion were reassessed. The predictive value of preoperative CEUS for postoperative shoulder function and tendon integrity was evaluated. 35 patients entered the statistical analysis. Preoperative CEUS-based assessment of SSP perfusion significantly correlated with early postoperative shoulder function (Constant, r = 0.48, p < 0.018) and tendon retear (r = 0.67, p < 0.001). CEUS-based subgroup analysis identified patients with exceptionally high, respectively low risk for tendon retear. CEUS-based assessment of the SSP seemed to predict early shoulder function and tendon retear after SSP repair and allowed to identify patient subgroups with exceptionally high or low risk for tendon retear. © 2019 The Authors. Journal of Orthopaedic Research® published by Wiley Periodicals, Inc. on behalf of Orthopaedic Research Society. J Orthop Res 38:1150-1158, 2020.

Safety Profile of Musculoskeletal Contrast-Enhanced Ultrasound with Sulfur Hexafluoride Contrast Agent

PURPOSE

Muscle, bone and tendon regeneration depend on the microperfusion of the corresponding tissue which can be quantified with contrast-enhanced ultrasound (CEUS) using sulfur hexafluoride contrast agent (SonoVue®). This study investigated the incidence of adverse events (AEs) in musculoskeletal patients and gives an overview of musculoskeletal CEUS applications.

PATIENTS AND METHODS

Based on 13 studies in a standardized monocentric setting, a total of 2268 CEUS examinations in 764 patients were performed and AEs due to the administration of sulfur hexafluoride contrast agent were classified as either mild, moderate or severe.

RESULTS

No fatal events occurred. AEs were reported in three cases, of which only one was classified as severe and two as mild. The total rate of all AEs was 0.13% and 0.04% for severe AEs.

CONCLUSION

The present analysis confirms the safety of musculoskeletal CEUS using sulfur hexafluoride contrast agent with a lower rate of AEs than that reported for other contrast agents even in elderly patients with concomitant diseases.

Intra-observer and Device-Dependent Inter-observer Reliability of Contrast-Enhanced Ultrasound for Muscle Perfusion Quantification

Muscle perfusion quantification by contrast-enhanced ultrasound (CEUS) may facilitate treatment decisions in musculoskeletal disorders. Translation into clinical routine relies on high intra-observer and inter-observer reliability and transferability between ultrasound devices to enable validation and multicenter studies. This study evaluates these aspects for deltoid muscle perfusion quantification, including possible multicenter study setups. One hundred sixty-six CEUS quantifications were conducted on 42 shoulders. Intra-observer reliability revealed a high intra-class correlation coefficient (ICC, r = 0.91) and low coefficient of variation (CV, 10.28%). Inter-observer reliability revealed an ICC of .84 and a CV of 17.1%, but these values decreased when different ultrasound devices were used (ICC = .60, CV = 18.6%). Re-evaluating subgroups with high sectional plane concordance significantly increased reliability (intra-observer: ICC = .97, CV = 5.49%, inter-observer/same device: ICC = .98, CV = 5.83%, varying devices: ICC = .78, CV = 9.8%). CEUS perfusion quantification of the deltoid seems applicable for multicenter studies, yet pooling different ultrasound devices remains critical. Sectional plane concordance appears to be crucial for reliability and transferability of CEUS muscle perfusion quantifications.

Relation between preoperative electromyographic activity of the deltoid and upper trapezius muscle and clinical results in patients treated with reverse shoulder arthroplasty

BACKGROUND

If patients susceptible to poor clinical outcomes could be predicted before reverse shoulder arthroplasty (RSA), it would help to set reasonable postsurgical patient expectations in the preoperative setting. Our hypothesis was that the preoperative electromyographic (EMG) activity of the deltoid and upper trapezius muscles would be correlated with clinical outcomes of patients undergoing RSA.

METHODS

EMG activity of the deltoid and upper trapezius muscles was measured in 25 patients scheduled to undergo RSA during 3 motions: shrugging, forward flexion, and abduction. Their postoperative clinical results were assessed prospectively during regular outpatient visits, including strength, active range of motion (ROM), pain, and functional scores. The correlations between the preoperative EMG activities and clinical results were analyzed.

RESULTS

Postoperative shoulder strength after RSA was increased in patients with greater preoperative EMG activity of the middle deltoid and upper trapezius. Preoperative EMG activity of the anterior or middle deltoid muscle was associated with active ROM in flexion or abduction, whereas EMG activity of the posterior deltoid was associated with active ROM in external rotation.

CONCLUSIONS

Shoulder strength after RSA was positively correlated with preoperative EMG activity of the deltoid and upper trapezius. Active ROM after RSA was positively correlated with preoperative EMG activity of the deltoid. Therefore, preoperative EMG measurements of the deltoid and upper trapezius may predict clinical outcomes after RSA.

Imaging of shoulder arthroplasties and their complications: a pictorial review

Currently, an increasing number of patients benefit from shoulder prosthesis implantation. Radiologists are therefore more often confronted with imaging examinations involving shoulder arthroplasty, whether during a dedicated examination or incidentally. Standard radiography is the first-line imaging modality in the follow-up of these implants, before the possible use of cross-sectional imaging modalities (computed tomography and magnetic resonance imaging), ultrasound, or nuclear medicine examinations. Shoulder arthroplasties are divided into three categories: reverse shoulder arthroplasty, total shoulder arthroplasty, and partial shoulder joint replacement (including humeral hemiarthroplasty and humeral head resurfacing arthroplasty). Each of these prostheses can present complications, either shared by all types of arthroplasty or specific to each. Infection, periprosthetic fractures, humeral component loosening, heterotopic ossification, implant failure, and nerve injury can affect all types of prostheses. Instability, scapular notching, and acromial fractures can be identified after reverse shoulder arthroplasty implantation. Glenoid component loosening and rotator cuff tear are specific complications of total shoulder arthroplasty. Progressive wear of the native glenoid is the only specific complication observed in partial shoulder joint replacement. Knowledge of different types of shoulder prostheses and their complications’ radiological signs is crucial for the radiologist to initiate prompt and adequate management.

[CEUS-application possibilities in the musculoskeletal system]

METHODICAL ISSUE

Contrast-enhanced ultrasound (CEUS) offers easily accessible visualization and quantification of the skeletal muscle microcirculation and other tissues in vivo and in real-time with almost no side effects.

AIM

The aim of this review is to present the increasing number of musculoskeletal CEUS applications.

METHODICAL INNOVATIONS/PERFORMANCE

CEUS applications regarding the musculoskeletal system include applications at bone and joints extending beyond the visualization of only the muscular microcirculation. Besides basic muscle physiology, impaired microcirculation in patients with peripheral artery disease or diabetes mellitus and the diagnosis of inflammatory myopathies have been the subject of previous CEUS studies. More recent studies in orthopedics and traumatology have focused on osseous and muscular perfusion characteristics, e. g., in differentiating infected and aseptic non-unions or the impact of different types of implants and prostheses on muscular microcirculation as a surrogate marker of clinical success.

PRACTICAL RECOMMENDATIONS

CEUS of the musculoskeletal system is used in clinical trials or off-label. Therefore, it is not well established in clinical routine. However, considering the increasing number of musculoskeletal CEUS applications, this could change in the future.

Healing Response of a Structural Hamstring Injury: Perfusion Imaging 8-Week Follow-Up

CONTEXT

Hamstring injuries are frequently observed in various sports disciplines both in elite and recreational sport.

OBJECTIVE

To quantify intramuscular tissue perfusion via contrast-enhanced ultrasound in the acute phase and during the healing of a structural muscle injury confirmed by high-resolution magnetic resonance imaging.

DESIGN

Case study.

SETTING

Laboratory environment.

PATIENT

A 32-year-old wakeboarder (height = 176 cm, body weight = 76 kg, and body mass index = 24.5 kg/m2) with an acute indirect muscle injury of the semimembranosus muscle.

MAIN OUTCOME MEASURES

Average values of quantifiable contrast-enhanced ultrasound, represented as peak enhancement and wash-in area under the curve, as well as conventional ultrasound, 1.5T magnetic resonance imaging were assessed at 48-hour, 3-week, and 8-week postinjury.

RESULTS

Average values of the quantitative perfusion analysis at 48-hour and 8-week postinjury revealed an approximate 5-fold increase in peak enhancement, and the wash-in area under the curve increased more than 3-fold in the center of the lesion. Magnetic resonance imaging, performed 48 hours after the injury to gather reference data as gold standard, revealed a grade III structural muscle tear.

CONCLUSIONS

The authors are able to demonstrate significant changes in intramuscular tissue perfusion in the center of the structural lesion as well as in the adjacent tissue. Quantifiable contrast-enhanced ultrasound seems to be able to gather relevant data for the assessment and monitoring of muscle injuries and could be established as a valuable tool for further studies focusing on healing processes or therapeutic interventions.

Effect of Compression Garments on the Development of Delayed-Onset Muscle Soreness: A Multimodal Approach Using Contrast-Enhanced Ultrasound and Acoustic Radiation Force Impulse Elastography

BACKGROUND

Delayed-onset muscle soreness (DOMS) is one of the most common reasons for impaired muscle performance in sports. However, little consensus exists regarding which treatments may be most effective, and the underlying mechanisms are poorly understood.

OBJECTIVES

To investigate the influence of compression garments on the development of DOMS, focusing on changes in muscle perfusion and muscle stiffness.

METHODS

In this controlled laboratory study with repeated measures, muscle perfusion and stiffness, calf circumference, muscle soreness, passive ankle dorsiflexion, and creatine kinase levels were assessed in participants before (baseline) a DOMS-inducing eccentric calf exercise intervention and 60 hours later (follow-up). After DOMS induction, a sports compression garment (18-21 mmHg) was worn on 1 randomly selected calf until follow-up, while the contralateral calf served as an internal control. Muscle perfusion was assessed using contrast-enhanced ultrasound (peak enhancement and wash-in area under the curve), while muscle stiffness was assessed using acoustic radiation force impulse (shear-wave velocities). A magnetic resonance imaging scan of both lower legs was also performed during the follow-up testing session to characterize the extent of exercise-induced muscle damage. Comparisons were made between limbs and over time.

RESULTS

Shear-wave velocity values of the medial gastrocnemius showed a significant interaction between time and treatment (P = .006), with the noncompressed muscle demonstrating lower muscle stiffness values at follow-up compared to baseline or to the compressed muscle. No significant differences in soleus muscle stiffness were noted between limbs or over time, as was the case for muscle perfusion metrics (peak enhancement and wash-in area under the curve) for the medial gastrocnemius and soleus muscles. Further, compression had no significant effect on passive ankle dorsiflexion, muscle soreness, calf circumference, or injury severity, per magnetic resonance imaging.

CONCLUSION

Continuous wearing of compression garments during the inflammation phase of DOMS may play an important role in regulating muscle stiffness; however, compression garments have no significant effects on intramuscular perfusion or other common clinical assessments. J Orthop Sports Phys Ther 2018;48(11):887-894. Epub12 Jun 2018. doi:10.2519/jospt.2018.8038.

Contrast-Enhanced Ultrasound Determines Supraspinatus Muscle Atrophy After Cuff Repair and Correlates to Functional Shoulder Outcome

BACKGROUND

Muscle degeneration as a consequence of rotator cuff tears is mainly assessed by magnetic resonance imaging. Contrast-enhanced ultrasound (CEUS) is a new functional imaging method to assess microvascular perfusion as a fundamental parameter of muscle tissue vitality. In this cross-sectional study, the authors evaluated supraspinatus muscle perfusion after cuff repair and analyzed its association with functional shoulder outcome and the grade of echogenicity in B-mode ultrasound indicating fatty infiltration.

HYPOTHESIS

The authors expected reduced microperfusion of the operated versus the contralateral supraspinatus muscle and a correlation of the muscular microperfusion with functional shoulder outcome.

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

Patients who received unilateral repair of the supraspinatus tendon between 2009 and 2014 were invited for a single follow-up examination. Functional scores were assessed, including the Constant-Murley score and American Shoulder and Elbow Surgeons score. CEUS examination was performed bilaterally in an oblique sagittal plane of the supraspinatus fossa. Perfusion was quantified by the parameters wash-in perfusion index (WiPI) and peak enhancement via VueBox quantification software. The results of the Constant-Murley score, American Shoulder and Elbow Surgeons score, and perfusion parameters were referenced to the contralateral shoulder. Echogenicity of the supraspinatus muscle was classified with a 3-point scale as compared with the trapezius muscle.

RESULTS

Sixty-seven patients were available, with a mean follow-up of 38.0 ± 18.5 months. Functional assessment showed impaired shoulder function on the operated shoulder as compared with the contralateral side (relative Constant Score [CS], 80% ± 19%). CEUS revealed diminished perfusion on the operated shoulder (WiPI, 55.1% ± 40.2%, P < .001). A strong correlation could be demonstrated between the perfusion deficit and functional impairment (relative WiPI and CS: r_s = .644, P < .001). Higher grade of echogenicity in B-mode ultrasound was associated with reduced perfusion.

CONCLUSION

CEUS could visualize impaired supraspinatus muscle perfusion after rotator cuff repair as compared with the contralateral, healthy shoulder. With its ability to quantify microvascular perfusion as a surrogate parameter for muscle vitality and function, CEUS may serve as a quantitative method to evaluate rotator cuff muscles.

Contrast-Enhanced Ultrasound as a New Investigative Tool in Diagnostic Imaging of Muscle Injuries-A Pilot Study Evaluating Conventional Ultrasound, CEUS, and Findings in MRI

OBJECTIVE

To emphasize the diagnostic value of contrast-enhanced ultrasound (CEUS) in the imaging of muscle injuries with different degrees of severity by comparing findings to established imaging modalities such as conventional ultrasound and magnetic resonance imaging (MRI).

DESIGN

Case series.

SETTING

Institutional study. Conventional ultrasound and CEUS were performed in the Department of Internal Medicine. Magnetic resonance imaging was carried out in the Department of Radiology within the Magnetom Avanto 1.5T and Magnetom Skyra fit 3T (Siemens Healthineers, Erlangen, Germany) and in the Institution of Imaging Diagnostics and Therapy (Magnetom Avanto 1.5T; Siemens, Erlangen, Germany).

PATIENTS

Fifteen patients who underwent an acute muscle injury were recruited.

MAIN OUTCOME MEASURES

The appearance and detectable size of muscle injuries were compared between each imaging modality. The injuries were assessed by 3 independent observers and blinded between imaging modalities.

RESULTS

All 15 injuries were identified on MRI and CEUS, whereas 10 injuries showed abnormalities in conventional ultrasound. The determination and measurement revealed significant differences between conventional ultrasound and CEUS depending on injury severity. Contrast-enhanced ultrasound revealed an impairment of microcirculation in grade I lesions (corresponding to intramuscular edema observed in MRI), which was not detectable using conventional ultrasound.

CONCLUSIONS

Our results indicate that performing CEUS seems to be a sensitive additional diagnostic modality in the early assessment of muscle injuries. Our results highlight the advantages of CEUS in the imaging of low-grade lesions when compared with conventional ultrasound, as this was the more accurate modality for identifying intramuscular edema.

The application of ultrasound elastography in the shoulder

Ultrasound elastography (EUS) is a recently developed method for the assessment of tissue elasticity by applying mechanical stress and subsequently analyzing tissue displacement with ultrasound. To date, mainly two different techniques are used in clinical practice: strain (compression) EUS and shear wave EUS. However, shear wave EUS has been shown to be more examiner independent and more reliable as this technique allows a quantitative measurement of tissue elasticity. There is increasing evidence that EUS can be used to evaluate mechanical properties of musculoskeletal tissue. Thus, it might be a powerful tool to detect and to monitor pathologic processes affecting the shoulder girdle. As ultrasound is an essential clinical tool for the examination of the shoulder, this review describes the two most important EUS techniques available for clinical use, presenting the published evidence on the applications of EUS for the evaluation of pathologic processes affecting the shoulder joint. In addition, technical issues, limitations, and future perspectives of these methods for the assessment of the shoulder are outlined.