Evaluation of Current Symptoms in Postoperative Achilles Tendons: A Multimodal Ultrasound Study

Abstract

(1) Background: It is unknown which imaging parameters are associated with clinical persistent symptoms in postoperative Achilles tendons. This study used B-Mode, Power Doppler (PD-US), Ultrasound Tissue Characterization (UTC) and Shear Wave Elastography (SWE) to investigate which imaging parameters are associated with persistent symptoms in postoperative Achilles tendon tissue. (2) Methods: Retrospective, cross-sectional, multimodal imaging study. Based on the VISA-A score, postoperative tendons were assigned to two groups: 1. asymptomatic (VISA-A ≥ 90, n = 18); 2. symptomatic (VISA-A < 90, n = 10). The following imaging parameters were analyzed: UTC (echo type I, II, III, IV), B-Mode (diameter, cross sectional area, calcification, fiber irregularity), PD-US (Öhberg score) and SWE (SWE 3 mm, SWE area) using a t-test and a Mann-Whitney U test. (3) Results: SWE and PD-US showed significantly reduced elasticity and increased neovascularization in symptomatic tendons (SWE 3 mm p = 0.031, SWE area p = 0.046, Öhberg score p < 0.001). The only significant correlation between imaging parameters and the VISA-A score was assessed for SWE 3 mm (r = 0.378; p = 0.047) and the Öhberg score (r = -0.737; p < 0.001). Conclusions: Symptomatic postoperative Achilles tendons showed increased neovascularization and lower SWE values than asymptomatic ones. Future studies should examine the diagnostic accuracy of PD-US and SWE in detecting current symptoms in postoperative Achilles tendons.

Keywords: Achilles tendon; Power Doppler; Shear Wave Elastography; Ultrasound Tissue Characterization; postoperative; surgery.

Figure 1

Flow chart of the study design.

Figure 2

B-Mode (B-US), Power Doppler (PD-US), Shear Wave Elastography (SWE) and Ultrasound Tissue Characterization (UTC): asymptomatic patient 12 months after midportion rupture and suture. There is no neovascularization, but focal hypoechogenicity and a thickened tendon in B-US and PD-US. For the insertion, SWE revealed high elastic properties (SWE 3 mm (black circle): 538.4 kPa (13.38 m/s) SD 12.3 kPa (2.02. m/s); SWE area (red rectangle): 469.5 kPa (12.49 m/s) SD 78.3 kPa (5.1 m/s), area 2.44 cm2). UTC shows a large area of echo type III (red—fibrillar matrix) in the midportion in the axial and longitudinal planes. UTC echo type I—intact and aligned tendon bundles (green); UTC echo type II—discontinuous wavy tendon bundles (blue); UTC echo type III—mainly fibrillar matrix (red); UTC echo type IV—mainly amorphous matrix (black).

Figure 3

Significant differences (*) between asymptomatic and symptomatic postoperative tendons could only be demonstrated in SWE 3 mm, SWE area and PD-US.