Achillodynia - Radiological Imaging of Acute and Chronic Overuse Injuries of the Achilles Tendon

Abstract

In the past decades the incidence of acute and chronic disorders of the Achilles tendon associated with sport-induced overuse has steadily increased. Besides acute complete or partial ruptures, achillodynia (Achilles tendon pain syndrome), which is often associated with tendon degeneration, represents the most challenging entity regarding clinical diagnostics and therapy. Therefore, the use of imaging techniques to differentiate tendon disorders and even characterize structure alterations is of growing interest. This review article discusses the potential of different imaging techniques with respect to the diagnosis of acute and chronic tendon disorders. In this context, the most commonly used imaging techniques are magnetic resonance imaging (MRI), B-mode ultrasound, and color-coded Doppler ultrasound (US). These modalities allow the detection of acute tendon ruptures and advanced chronic tendon disorders. However, the main disadvantages are still the low capabilities in the detection of early-stage degeneration and difficulties in the assessment of treatment responses during follow-up examinations. Furthermore, differentiation between chronic partial ruptures and degeneration remains challenging. The automatic contour detection and texture analysis may allow a more objective and quantitative interpretation, which might be helpful in the monitoring of tendon diseases during follow-up examinations. Other techniques to quantify tendon-specific MR properties, e.?g. based on ultrashort echo time (UTE) sequences, also seem to have great potential with respect to the precise detection of degenerative tendon disorders and their differentiation at a very early stage. Key Points: Citation Format:

Everything Achilles: Knowledge Update and Current Concepts in Management

“…T he Achilles tendon is the most commonly ruptured tendon 2 , and the incidence of injuries is increasing 13 . Injury causes are often multifactorial, related to overuse combined with mechanical overload and host susceptibility 14 .…”

Partial Achilles Tendon Rupture—A Neglected Entity: A Narrative Literature Review on Diagnostics and Treatment Options

“…The majority of studies report that with ultrasound it is difficult to distinguish partial ruptures from focal degenerative changes, since partial ruptures appear with a wavy, irregular echo pattern with accompanying focal hypoechogenic areas, detectable neovascularization, and tendon thickening that are also findings in Achilles tendinopathy [ 19 , 23 , 26 , 28 , 29 ]. A more specific finding might be a disrupted dorsal Achilles tendon border [ 19 , 28 ] ( Figure 2 a). The detection of proximal partial ruptures close to the myotendinous junction and the differentiation between older partial ruptures and intratendinous tendinopathy are challenging with ultrasound [ 28 , 30 ] ( Figure 2 b).…”

“…A more specific finding might be a disrupted dorsal Achilles tendon border [ 19 , 28 ] ( Figure 2 a). The detection of proximal partial ruptures close to the myotendinous junction and the differentiation between older partial ruptures and intratendinous tendinopathy are challenging with ultrasound [ 28 , 30 ] ( Figure 2 b). In MRI, a partial tear is defined as tendon thickening with a hyperintense signal on T1 and a strong hyperintense signal on magnetic resonance (MR) images with fluid-sensitive (T2-weighted and inversion recovery) sequences [ 29 , 30 , 31 ] ( Figure 3 ).…”

The Vienna morphological Achilles tendon score—VIMATS

“…The MRI examinations were performed on a 3.0 T whole-body Magnetom TimTrio scanner (Siemens Healthcare, Erlangen, Germany), using a gradient strength of 40 mT/m and an 8‑channel coil (In vivo, Gainesville, FL, USA). The standard MRI protocol [ 10 ] was identical for all examinations and consisted of a set of localizers and three morphological MRI sequences: 1) a sagittal fat-suppressed (fs) proton density-weighted (PD-w) turbo spin echo (TSE) sequence (TR 3970 ms, TE 26 ms, FoV 220 × 220 mm, TA 3:55 min); 2) a sagittal T1‑w spin echo (SE) sequence (TR 724 ms, TE 11 ms, FoV 220 × 220 mm, TA 3:22 min) and 3) an axial T2‑w TSE sequence (TR 6720 ms, TE 100 ms, FoV 170 × 170mm, TA 3:22 min). Total imaging time including positioning and registration of the patient was around 15 min.…”

“… Tendon insertion area abnormalities (‑5 points) Alterations at the insertion site of the AT include enthesiophytes and ossification (sagittal T1‑w SE images), as well as cystic alterations and bone marrow edema (on sagittal fs PD‑w TSE and axial T2 images) at the transition from the insertion zone to the calcaneal bone. Peritendinitis or edema of Kager’s fat pad (‑5 points) On T2‑w and PD‑w MRI sequences, peritendinitis appears as a linear or reticular high signal area alongside the deep surface as well as the subcutaneous surface of the tendon, representing an area of edema, thickened peritendinous tissue with fibrinous exudate, or increased vascularity [ 2 , 10 ]. Edema of Kager’s fat pad is present if high signal is seen within the fat pad on the sagittal fs PD‑w TSE images.…”