UBC Theses and Dissertations

UBC Theses Logo

UBC Theses and Dissertations

The free Achilles tendon is longer in those with midportion Achilles tendinopathy : an MRI case-control study Callow, Joanne Hazel


Rationale: The distal attachment of the triceps surae muscle onto the Achilles tendon is variable, leading to inter-individual diversity in the length of the free Achilles tendon. A longer free tendon may be more prone to injury due to reduced muscular buttressing. Objective: The purpose of this study was to compare the free Achilles tendon dimensions and structure between those with midportion or insertional Achilles tendinopathy (AT) and healthy controls using magnetic resonance imaging (MRI). Methods: MRI scans from 132 patients were compared. The insertional AT group consisted of 25 patients (median age 61, height 163 cm, weight 81.7 kg) and were matched by 25 controls (median age 55, height 168 cm, weight 78 kg). The midportion AT group consisted of 41 patients (median age 55, height 168 cm, weight 83.9 kg) and were matched by 41 controls (median age 52, height 170 cm, weight 77.1 kg). The primary outcome measure was free Achilles tendon length. Secondary outcome measures included cross-sectional area (CSA), anteroposterior thickness, location of pathology and extent of pathology. All measurements were assessed twice and the mean was reported. Results: Midportion AT cases had significantly longer free tendons (Mdn = 51.2 mm, IQR = 26.9 mm) compared to controls (Mdn = 40.8 mm, IQR = 20.0 mm), p = .007. However, there was not a significant difference between the free Achilles tendon lengths in insertional AT cases (Mdn = 47.9 mm, IQR = 15.1 mm) and controls (Mdn = 39.2 mm, SD = 17.9 mm), p = .158. Free Achilles tendon length was also correlated with the extent of pathology among those with AT, rτ = 0.18, p = .03. Conclusion: Having a long free Achilles tendon is associated with the presence of midportion Achilles tendinopathy.

Item Media

Item Citations and Data


Attribution-NonCommercial-NoDerivatives 4.0 International