Real-time sonoelastography of the Achilles tendon: pattern description in healthy subjects and patients with surgically repaired complete ruptures

Tendon quality in small unilateral supraspinatus tendon tears. Real-time sonoelastography correlates with clinical findings

PURPOSE

To investigate the feasibility of real-time sonoelastography in the assessment of the mechanical tendon properties in small unilateral supraspinatus tears, to describe the sonoelastographic properties of the torn supraspinatus tendons and to correlate real-time sonoelastography findings with clinical results and demographic data.

METHODS

All the patients presenting for a unilateral rotator cuff tear were prospectively scrutinized. Clinical evaluation included complete physical examination, VAS, Quick DASH, Constant-Murley score, Simple Shoulder Test, ASES score and UCLA score. Radiological evaluation was performed with conventional ultrasounds and real-time sonoelastography; this is a noninvasive method that uses ultrasounds to evaluate the mechanical properties of tissues, reflecting their quality, that can be semi-quantitatively estimated using the strain index. During the enrolment period, 92 patients were scrutinized, and 50 were included in the study.

RESULTS

A negative correlation between strain index and VAS for pain, a strong positive correlation between strain index and Constant-Murley score and ASES score were found. Comparable results were observed in male and female patients, but in males, we found a strong positive correlation also for Simple Shoulder Test and UCLA score.

CONCLUSIONS

Real-time sonoelastography was a feasible method applicable in the assessment of tendon quality in small supraspinatus tears, and its findings correlated with the clinical results of the patients. In day-by-day clinical practice, this information is very important because quality of tendons is one of the most important prognostic factors for surgeons performing rotator cuff repair.

LEVEL OF EVIDENCE

III.

Sonoelastography: musculoskeletal applications

All participants for image samplings provided written informed consent. Conventional B-mode ultrasonography (US) has been widely utilized for musculoskeletal problems as a first-line approach because of the advantages of real-time access and the relatively low cost. The biomechanical properties of soft tissues reflect to some degree the pathophysiology of the musculoskeletal disorder. Sonoelastography is an in situ method that can be used to assess the mechanical properties of soft tissue qualitatively and quantitatively through US imaging techniques. Sonoelastography has demonstrated feasibility in the diagnosis of cancers of the breast and liver, and in some preliminary work, in several musculoskeletal disorders. The main types of sonoelastography are compression elastography, shear-wave elastography, and transient elastography. In this article, the current knowledge of sonoelastographic techniques and their use in musculoskeletal imaging will be reviewed.

"Soft, hard, or just right?" Applications and limitations of axial-strain sonoelastography and shear-wave elastography in the assessment of tendon injuries

Injury to a tendon leads to alterations in the mechanical properties of the tendon. Axial-strain sonoelastography and shear-wave elastography are relatively new, real-time imaging techniques that evaluate the mechanical properties of tendons in addition to the existing morphological and vascular information that is obtained with traditional imaging tools. Axial-strain sonoelastography displays the subjective distribution of strain data on an elastogram caused by tissue compression, whereas shear-wave elastography provides a more objective, quantitative measure of the intrinsic tissue elasticity using the acoustic push-pulse. Recent studies suggest that axial-strain sonoelastography is able to distinguish between asymptomatic and diseased tendons, and is potentially more sensitive than conventional ultrasound in detecting early tendinopathy. Shear-wave elastography seems to be a feasible tool for depicting elasticity and functional recovery of tendons after surgical management. While initial results have been promising, axial-strain sonoelastography and shear-wave elastography have not yet found routine use in wider clinical practice. Possible barriers to the dissemination of axial-strain sonoelastography technique include operator dependency, technical limitations such as artefacts and lack of reproducibility and quantification of sonoelastography data. Shear-wave elastography may improve the reproducibility of elastography data, although there is only one published study on the topic to date. Large-scale longitudinal studies are needed to further elucidate the clinical relevance and potential applications of axial-strain sonoelastography and shear-wave elastography in diagnosing, predicting, and monitoring the progress of tendon healing before they can be widely adopted into routine clinical practice.

Value of adding sonoelastography to conventional ultrasound in patients with congenital muscular torticollis

BACKGROUND

Sonoelastography has been utilized to evaluate various myopathies. However, the benefits of adding sonoelastography to conventional ultrasound (US) in patients with congenital muscular torticollis are unclear.

OBJECTIVE

To evaluate the value of adding sonoelastography to conventional US in patients with congenital muscular torticollis.

MATERIALS AND METHODS

This study included 27 infants clinically diagnosed with congenital muscular torticollis and 17 healthy infants who underwent conventional US and sonoelastography. The echogenicity of the sternocleidomastoid muscle was assessed as isoechoic, heterogeneous, hyperechoic or hypoechoic compared with normal muscle. The thickness of the involved and contralateral sternocleidomastoid muscles was measured. Elastographic findings were scored from 1 (soft) to 3 (hard) by two independent radiologists.

RESULTS

The sternocleidomastoid muscle thickness, difference and ratio between involved and normal sternocleidomastoid muscle thickness, and elastographic score differed significantly between the patient and control groups. Of the 27 patients, 11 had isoechoic, 5 had heterogeneous and 11 had hyperechoic muscles. Congenital muscular torticollis patients with isoechoic muscle showed significantly higher elastographic scores than the control group, but there were no other significant differences by conventional US.

CONCLUSIONS

Adding sonoelastography to conventional US is helpful for the diagnosis of congenital muscular torticollis, especially in patients with isoechoic sternocleidomastoid muscle.

Ultrasound elastography is a reproducible and feasible tool for the evaluation of the patellar tendon in healthy subjects

OBJECTIVE

To evaluate the feasibility and reproducibility of ultrasound elastography (UE) in the assessment of healthy patellar tendon and to describe its UE pattern.

METHODS

Twenty-two patellar tendons of 11 out of 16 healthy subjects who met the inclusion criteria were evaluated three times by ultrasound (US) and UE at their proximal, middle and distal portions, by two separate sonographers with different experiences in UE.

RESULTS

In all tendon portions the color map analysis showed a predominance of green (highly elastic), with good values of intra-observer (Operator 1: P-values = 0.790, 0.864, 0.865; Operator 2: P = 0.642, 0.882, 0.613 for proximal, middle and distal portions, respectively) and inter-observer (P = 0.657) agreement. For both operators the intra-observer analysis of the elasticity ratio (ER) between the tendon and the subcutis showed high agreement values (P < 0.001 for both operators). The inter-observer analysis showed also high agreement values (P < 0.001 at proximal, P = 0.001 at middle, P = 0.005 at distal portions). The overall analysis of the ER of the tendon portions showed values of (mean ± SD): 1.47 ± 0.64, 4.38 ± 1.36, 3.32 ± 1.20 for proximal, middle and distal portions, respectively. The mean time to perform the UE evaluation for the inexperienced operator was 5 min at the beginning of the study but decreased to 2 min after a few examinations were done. The mean time for the expert was 2 min for the entire study.

CONCLUSIONS

UE is a feasible and reproducible tool for the evaluation of the healthy patellar tendon and further data are needed to define its role in the assessment of tendon pathology.

Real-time sonoelastography of Achilles tendon in patients with ankylosing spondylitis

OBJECTIVE

Real-time sonoelastography (SE) is a new ultrasound-based imaging technique that provides information on tissue elasticity and stiffness. We determined the efficacy of SE for assessing Achilles tendon abnormalities in patients with ankylosing spondylitis (AS).

MATERIALS AND METHODS

Forty-one consecutive AS patients and 32 asymptomatic healthy subjects were enrolled. Achillodynia was scored on a 0- to 100-mm visual analog scale. A high-resolution ultrasound machine equipped with an elastography-compatible linear probe was used to perform bilateral B-mode ultrasound, Doppler ultrasound, and SE examinations of Achilles tendons. Tendons were divided into proximal, middle, and distal segments. B-mode examinations included tendon thicknesses, echotextures, and enthesopathic findings. SE using color-coded images was performed in the same areas. Normal consistent tendon structures were coded as blue or green, and moderately (yellow) or severely (red) softened areas were considered pathological.

RESULTS

The distal third of the Achilles tendons was the most commonly affected part in the AS patients compared with healthy subjects (p = 0.001), whose middle third was more commonly affected. Achillodynia intensity tended to be higher in patients with pathological B-mode or SE examination findings (p = 0.09 and p = 0.07 respectively). Softening detected by SE in the distal third was associated with enthesopathy findings such as calcaneal bone erosions (Fisher's X (2), p = 0.07) and tendinous enlargement (Fisher's X (2), p = 0.001). B-mode and SE findings had moderate to good correlation in the assessment of Achilles tendon abnormalities.

CONCLUSIONS

Sonoelastography may be useful for the evaluation of tendon abnormalities in patients with AS; in addition; it may be useful for the evaluation of other inflammatory rheumatic conditions.

Update on ultrasound elastography: miscellanea. Prostate, testicle, musculo-skeletal

Nowadays ultrasound elastosonography is an established technique, although with limited clinical application, used to assess tissue stiffness, which is a parameter that in most cases is associated with malignancy. However, although a consistent number of articles have been published about several applications of elastosonography, its use in certain human body districts is still not well defined. In this paper we write on the use of elastosonography in prostate, testicle and musculo-skeletal apparatus. We report and compare the work of several authors, different type of elastosonography (shear wave, strain elastography, etc.) and instrumental data obtained in the study of both benign and malignant lesions.