The impact of Achilles tendon thickness and Kager's fat pad thickness on clinical and functional outcomes following open surgical repair of acute Achilles tendon rupture

Abstract

BACKGROUND: Acute Achilles tendon ruptures (ATR) are among the most common sports-related injuries. The aim of this study was to evaluate the correlation between Achilles tendon (AT) and Kager's fat pad (KFP) thickness with clinical and functional out-comes, measured using the Achilles Tendon Rupture Score (ATRS) and the Foot and Ankle Outcome Score (FAOS), in patients treated with open surgical repair for acute ATR. METHODS: This retrospective study included 42 patients who underwent surgery for ATR at our institution between January 2017 and December 2021. All patients were treated using the open surgical Krackow suture technique. ATRS, FAOS, and Visual Analogue Scale (VAS) scores were recorded one year postoperatively. AT and KFP thicknesses were measured via ultrasonography by an independent radiologist at one-year follow-up. RESULTS: The mean age of the patients was 45.38 +/- 9.68 years, with 22 male patients (52.4%). The mean ATRS was 65.17 +/- 24.46, the mean FAOS was 76.14 +/- 16.75, and the mean VAS score was 3.02 +/- 1.44. The mean AT thickness on the operated side was 15.54 +/- 2.89 mm, compared to 14.58 +/- 2.28 mm on the contralateral side (p=0.009). The mean KFP thickness on the operated side was 8.42 +/- 2.99 mm, compared to 6.32 +/- 2.67 mm on the contralateral side (p=0.005). A strong correlation was found between ATRS and FAOS (r=0.742, p<0.001). For AT thickness, there were moderate negative correlations with both ATRS and FAOS (r=-0.544, p=0.013; r=-0.451, p=0.003, respectively). For KFP thickness, a moderate negative correlation was found with ATRS (r=-0.506, p=0.001). CONCLUSION: AT and KFP thicknesses had no significant direct effect on ATRS and FAOS. However, ATRS and FAOS scores fol-lowing open surgical repair of acute ATR were correlated with each other and with functional outcomes. Despite its specific complica-tions, open surgical repair of acute ATR is an effective option for patients eligible for surgery.