Morphological and Functional Outcomes >13 Years After Achilles Tendon Rupture Treated Operatively and Non-operatively

OBJECTIVES: In patients >13yrs after treatment for acute Achilles tendon rupture (AATR), 1) investigate side-to-side differences in MRI-defined morphological changes in the Achilles tendon and surrounding calf musculature, 2) investigate side-to-side differences in single-limb functional tasks, and 3) compare patients who received operative vs non-operative treatment. METHODS: 28 patients (11 operative, 17 non-operative) from a previous randomized trial returned 15±1 years post-AATR for testing (age: 57±7 years; BMI: 30±5 kg/m2). Patients underwent bilateral 3T MRI (MAGNETOM Prisma, Siemens) including sagittal and axial T1 and T2-weighted turbo spin echo (TSE), axial T1-weighted inversion recovery, and sagittal T2-weighted 3D isotropic TSE sequences. The maximum anteroposterior Achilles tendon diameter (MAD) and cross-sectional area (CSA), distance from the MAD to the superior margin of the calcaneus, tendon length, gastrocnemius and soleus CSA, and calf circumference were measured using distance and area software tools (Figure 1; AGFA Healthcare). Functional measures included single-legged heel-rise repetitions and maximum vertical jump height. All outcomes were compared between limbs and between groups. RESULTS: Overall, there were significant side-to-side differences in most MRI and functional measures, with the injured limb Achilles tendon typically wider and thicker (MAD often twice as large), calf musculature CSA smaller, number of heel raises lower, and vertical jump height lower (Table 1). The only differences between treatment groups was in MAD and the distance from the MAD to the superior margin of the calcaneus, with a greater side-to-side difference for patients treated operatively (Table 1). CONCLUSION: Substantial side-to-side differences in tendon diameter, thickness, muscle bulk and functional performance persist beyond a decade after treatment for AATR. There were no differences favoring operative treatment over non-operative treatment.