The Role of Sonoelastography in the Diagnosis of Supraspinatus Tendinosis

Research Article

Austin J Musculoskelet Disord. 2021; 8(1): 1056.

The Role of Sonoelastography in the Diagnosis of Supraspinatus Tendinosis

Cavalieri S¹, Negroni D¹, Vinco A¹, Zagaria D¹*, Guglielmi R² and Carriero A¹

¹Department of Diagnosis and Treatment Services, Radiodiagnostics, Azienda Ospedaliero Universitaria Maggiore della Carità, Novara, Italy

²Istitute of Radiology, Spital Thurgau, AG Cantonel Hospital, Munsterlingen, Switzerland

*Corresponding author: Domenico Zagaria, Department of Diagnosis and Treatment Services, Radiodiagnostics, Azienda Ospedaliero Universitaria Maggiore della Carità, Novara, Italy

Received: March 15, 2021; Accepted: April 20, 2021; Published: April 27, 2021


Purpose: The aim of the study was to evaluate the sensitivity and specificity of compressive elastosonography (“Strain Elastography”), integrated with the B-mode ultrasound examination, in supraspinatus tendinosis, using magnetic resonance imaging as the gold standard for diagnosis.

We also verified the intra-observer reproducibility of this elastosonographic method.

Materials and Methods: The supraspinatus tendons of 30 patients with shoulder pain and positive magnetic resonance imaging for tendinosis were examined with B-Mode ultrasound and compressive elastosonography in the absence of full-thickness tendon ruptures. At the same time, 30 control individuals, asymptomatic for shoulder pain and with a negative history of previous diseases affecting the rotator cuff, were examined with B-Mode ultrasound and compressive elastosonography.

The MRI exam was used as a gold standard reference exam for the diagnosis of tendinosis. At the “Strain” elastosonography the images were evaluated qualitatively with the color elastogram and quantitatively with the percentages of deformation of the supraspinatus tendon (Strain T), of the deltoid muscle used as reference tissue (Strain R) and of the SR/ST ratio (Ratio).

Results and Conclusions: The comparison between the group of individuals with tendinosis and the control group shows a statistically significant difference (p<0.05) for the Ratio values (SR/ST), respectively: 4.7 ± 0.14 vs 5.3 ± 0.19.

The different Ratio values indicate that the supraspinatus tendon, when compared with the deltoid muscle, is softer in patients with tendinosis than in the control group. As indicated by the statistical analysis of the ROC curve, the Ratio value of 4.8 represents the best sensitivity and specificity data (70% and 61% respectively). Elastosonography can therefore provide added value, compared to the conventional ultrasound examination only, to confirm the diagnosis of supraspinatus tendinosis. The analysis showed a low variance of results, due to its excellent intra-observer reproducibility (intraclass correlation coefficient = 0.86).

Future studies could aim to describe any changes in Stain T, Strain R and Ratio values in a cohort of individuals stratified by gender, age and BMI.

Keywords: Diagnostic imaging; Ultrasonography; Elastography; Share wave; Tendons; Muscle


Rotator cuff tendinopathy is the leading cause of shoulder pain and the supraspinatus tendon is the most frequently involved [1,2]. Studies have shown that the prevalence of rotator cuff pathology fluctuates between 5% and 40% and that the prevalence increase is directly related to the age of the patients [3].

Shoulder ultrasound is a diagnostic imaging method widely used in clinical practice, which has the advantages of non-invasiveness, low cost and high tolerability.

In the literature there is a variability regarding the diagnostic accuracy of ultrasound in diagnosing tendinopathy of the rotator cuff tendons, this variability is influenced by the intrinsic limits of it and the experience of the clinician/sonographer [4].

Elastosonography is an ultrasound imaging technique capable of obtaining qualitative and quantitative information on tissues’ stiffness. It studies the physical properties of elasticity, based on the principle that an external force (e.g. manual compression with the probe) applied to a tissue induces a deformation of the tissue itself; the deformation induced is greater in softer tissues and lesser in harder tissues. This method was initially used in the diagnostic imaging of diseases of the liver, thyroid, breast, prostate, cervix and lymph nodes [5-9] and subsequently also in the study of the musculoskeletal system [10-13].

Currently two different techniques can be used in clinical practice: the “Strain” (compression) elastosonography and the “Shear Wave”. The “Strain” technique uses manual compression, while the “Shear Wave” technique requires the mechanical impulse to be generated by the ultrasound probe itself.

Both forms of elastosonography evaluate tissue stiffness, which is measured by Young’s modulus.

Young’s modulus can be calculated with the following equation:


where E is Young’s modulus measured in Pascals (Pa), σ is the externally applied force (“stress” measured in Pa), and ε is the strain, which is a unitless measure of the relative elongation of the tissue [14,15].

The “Strain Elastography” method was the first form of elastosonography to be developed with Ophir et al. in the early 1990s [16].

The operator exerts an external force through repeated compressions using the ultrasound probe.

The compressed tissue analysis can be visualized as a deformation map (elastogram) which allows a qualitative assessment of the tissue stiffness.

Most elastograms allow you to highlight different levels of stiffness (hard, intermediate and soft tissue) by means of a colour scale. It is also possible to carry out a quantitative analysis by placing ROIs that detect the percentage of deformation of the sampled tissue [17,18].

Few scientific research used compressive elastosonography for the evaluation of the supraspinatus tendon, highlighting how this method can provide additional data about the presence of tendinosis compared to the conventional ultrasound examination alone. Our study aims to confirm the possible added value of “Strain Elastography” in the diagnosis of supraspinatus tendinosis and to evaluate its intra-observer reproducibility by comparing it with shoulder MR, which we use as reference.

Materials and Methods

The cases were selected from symptomatic patients for shoulder pain with a diagnostic MRI study positive for degenerative changes of the supraspinatus tendon, in the absence of complete or focal full-thickness tendon ruptures. On the same day that the magnetic resonance was performed, the ultrasound evaluation in B-mode and the investigation with the compressive elastosonographic technique were carried out.

The controls were chosen from individuals asymptomatic for shoulder pain with a negative history of previous or current joint diseases, selected from the general population. This last group underwent B-mode ultrasound and elastosonographic examination but not magnetic resonance investigation.

Since our study protocol does not involve drugs or invasive procedures and we carried out diagnostic tests in compliance with the standards, there was no risk expected for the study subjects.

Nonetheless, each participant to the study received a face to face explanation about the study protocol and goals, was offered the chance to ask questions and then filled in and signed a consent form. Throughout the study period, each subject was treated according to the standards of Good Clinical Practice [19].

We used the following:

• Philips “Achieva” and “Ingenia” 1.5 Tesla high-field magnetic resonance devices;

• Toshiba “APLIO 500” ultrasound device with linear probe - type: PLT-1204BX 18LX7 - broadband and high frequency (from 7 to 18 Mhz) and module for the elastosonographic investigation in “Strain Elastography” mode;

• Microsoft “Excel” software for data archiving and analysis.

Study population

From February 2020 to August 2020, we enrolled patients who met the following inclusion criteria: 1) age eighteen or older; 2) for the case group: patients with shoulder pain; 3) for the case group: patients who were already due to perform an MR investigation of the shoulder and whose MR study showed tendon changes of the supraspinatus; 4) for the control group: asymptomatic subjects for shoulder pain and with no history of previous shoulder pathologies.

Subjects with the following criteria were excluded or not enrolled in the study: 1) previous surgery on the affected shoulder; 2) performing an MRI examination of the shoulder with intra-articular administration of paramagnetic contrast (arthro-MRI); 3) a diagnosis of neuromuscular and / or connective tissue diseases; 4) pregnancy or breastfeeding in progress; 5) for the case group: the presence of complete or focal full-thickness tear of the supraspinatus tendon, documented in a previous MRI study.

Patients included in the study underwent B-Mode ultrasound and “Strain” (compression) Elastosonography in order to confirm the pathological changes of the supraspinatus tendon found on magnetic resonance imaging and to collect the quantitative elastosonographic values of Strain T, Strain R and Ratio.

A basic patient’s history was also collected: gender, age, duration of shoulder pain expressed in months (if belonging to cases), shoulder affected by painful symptoms and dominance (right-handed or lefthanded).

The MR study was read by a senior radiologist with 15 years of experience in MSK radiology and acted as our gold standard for the diagnosis of supraspinatus tendinosis.

The MR study was performed in baseline conditions, following the standard protocols for the evaluation of the shoulder, by means of weighted sequences in DP, DP SPAIR and STIR, oriented on the three orthogonal planes of the space according to the shoulder’s anatomy. The following were considered as tendinosis findings: a hyperintensity of focal or diffuse intra-tendon signal in long TR sequences, such as from mucoid degeneration, associated with tendon thickening. Conversely, a focal full thickness tear or a complete tear of the tendon were considered as rupture findings [20].

For the ultrasound examination the patient was placed in a sitting position, with the arm behind the back and the elbow flexed 90 degrees, in order to better expose the supraspinatus moving it away from the acromion of the scapula, thus allowing a complete visualization of the tendon [21].

The ultrasound evaluation in B-Mode considered as signs of tendinosis: a thickening (increase in thickness versus healthy controls) with hypoechogenicity, sometimes inhomogeneous and a loss of the tendon’s fibrillar structure [22] (Figure 1).