The correlations between dimensions of the normal tendon and tendinopathy changed Achilles tendon in routine magnetic resonance imaging

Abstract

This comparative study aimed to investigate how tendinopathy-related lesions change correlations in the dimensions of the Achilles tendon. Our experimental group included 74 patients. The mean age was 52.9 ± 10.4 years. The control group included 81 patients with a mean age was 35.2 ± 13.6 years, p < .001. The most significant difference in correlation was the thickness of the tendon and the midportion's width, which was more significant in the tendinopathy (r = .49 vs. r = .01, p < .001). The correlation was positive between width and length of the insertion but negative in normal tendons (r = .21 vs. r = - .23, p < .001). The correlation was between the midportions width in tendinopathy and the tendon's length but negative in the normal tendon (r = .16 vs. r = - .23, p < .001). The average thickness of the midportion in tendinopathy was 11.2 ± 3.3 mm, and 4.9 ± 0.5 mm in the control group, p < .001. The average width of the midportion and insertion was more extensive in the experimental group, 17.2 ± 3.1 mm vs. 14.7 ± 1.8 mm for the midportion and 31.0 ± 3.9 mm vs. 25.7 ± 3.0 mm for insertion, respectively, p < .001. The tendon's average length was longer in tendinopathy (83.5 ± 19.3 mm vs. 61.5 ± 14.4 mm, p < .001). The dimensions correlations in normal Achilles tendon and tendinopathic tendon differ significantly.

Figure 1

Dimensions of the Achilles tendon. (a) and (b) sagittal section, (c) and (d) transverse section. Section c was made at level E. Section d was made in the middle of distance D. A, B, C, D, E and F – dimensions of the Achilles tendon, as explained in the Material and Methods.

Figure 2

Differences in the average dimensions of the Achilles tendon in experimental and control group. The vertical axis represents millimeters, horizontal axis represents dimensions A–G; definitions are in the Material and Methods. The figure was prepared in Excel (version 16.46).

Figure 3

Midportion tendinopathy of the right Achilles tendon in a 45-year-old male who used to run about 3–5 km per day presenting with Achilles pain. Clinical diagnosis of tendinopathy was made with a suspicion of partial rupture. MRI showed a spindle-shaped Achilles tendon with alterations in the signal in the thickened part. (a)- Sagittal section, PD- weighted TSE, (b) axial section PD- weighted SPAIR.

Figure 4

Insertion of the left Achilles tendon. A 61-year-old male who suffered from Achilles pain for eight months, with acute Achilles tendon pain one week before examination. Tendinopathy with partial rupture was suspected. A, B, C, D, F, G—dimensions of the Achilles tendon; definitions in the Material and Methods. (a) and (b) Sagittal T2-weighted FSE (fast spin echo), (c)- sagittal PD-weighted FS (fat suppression), (d) and (e) axial PD-weighted FS.

Figure 5

The normal Achilles tendon. A 34-year-old female with clinical suspicion of a nerve tumor on n. tibialis. (a) PD- weighted SPAIR, (b) T1-weighted, (c) and (d) PD- weighted TSE SPAIR.

Figure 6

Diameters of the normal Achilles tendons in two patients. (a) and (b) a 34-year-old female with clinical suspicion of enthesopathy of the Achilles tendon, (c) a 28-year-old male with clinical suspicion of myositis. (a) and (b) axial section, PD-weighted FS, (c) T1-weighted.

Figure 7

Diameters of the Achilles tendon with midportion tendinopathy of the left Achilles tendon in a 52-year-old male who presented with Achilles pain. Clinical suspicion of tendinopathy with partial rupture. MRI showed an advanced tendinopathy. A, B, C, D, F, G—dimensions of the Achilles tendon; definitions in the Material and Methods. (a) sagittal section PD- weighted, (b) PD- axial section weighted FS, (c) axial section T1- weighted, (d) axial section PD- weighted FS.