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Introduction We investigated Achilles tendon structure, strength, and function one year or more after Achilles Tendon Rupture (ATR) managed non-surgically using the Leicester Achilles Management Protocol (LAMP).Materials and Methods This cross-sectional study recruited individuals ≥12 months post ATR. Structure was assessed using Ultrasound Tissue Characterisation (UTC): Cross-Sectional Area (CSA) of Aligned Fibrillar Structure (AFS) and Disorganised Fibrillar Structure (DFS). Plantarflexor strength using maximal voluntary isometric contraction (MVIC) and the calf raise test. Patient-reported outcomes included the Achilles tendon rupture score (ATRS), EQ-5D-5L. Achilles tendon resting angle (ATRA) indirectly measured tendon elongation. The relationship between outcomes and time since ATR was analysed using linear regression adjusting for age, sex, ethnicity, and Body Mass Index (BMI).Results Sixty participants (mean age 55.2 years, 78.5% male) were assessed at a mean of 6.8 years post ATR. The affected tendon showed a 62% larger CSA, with 28.7mm2 (16%) DFS compared to 7.3mm2 (7%) on the non-affected side (p<0.001). Linear regression showed decreasing AFS with time post-injury (p=0.04); no significant associations were found for CSA or DFS. Significant deficits were observed in plantarflexor strength, with MVIC and calf raise work 18% and 40% lower in the affected limb (p<.001). ATRA indicated tendon elongation in the affected limb of 6.7° (p<0.001). Median ATRS was 83, EQ-5D index 0.95, EQ-5D VAS 85.Conclusion Significant structural and functional deficits persist years after ATR, including increased tendon size, fibre disorganisation, reduced muscle strength/endurance, and tendon elongation. ATRS scores were consistent with previous non-surgical protocol outcomes in the UK.