Achilles tendon Thickness by High Resolution Ultrasonography in a Healthy Adult Population

The objective of this study was to derive a population-specific normogram for Achilles tendon in Nigeria and to determine its variation with age, gender and body mass index (BMI). This was a prospective cross sectional study of 154 subjects in a health facility in Lagos, South West Nigeria. With each subject in the prone position each Achilles tendon was scanned in the longitudinal and transverse planes using a 5MHz linear transducer. The thickness and cross sectional area (CSA) of the tendon were measured at the level of the medial malleolus. Each individual's weight and height were measured and Body Mass Index calculated. Data were analysed using SPSS software version 20. The mean Achilles tendon antero-posterior diameter (AT-AP) for both legs is 11.76 ± 1.71 mm, mean width, 12.95 ± 1.67mm and mean cross sectional area (CSA) is 120.93 ± 31.18mm2.The right Achilles tendon mean (AT-AP) diameter is11.95 ± 1.78 mm, width, 13.11 + 1.77 mm and CSA is 124.61mm2. For the left Achilles tendon the corresponding dimensions are11.57 + 1.63 mm, 12.80 + 1.56 mm and 117.25mm2 + 27.43 respectively. There is a significant difference in the tendon CSA between the right and left tendons (p<0.05).Female AT-AP diameter is thinner than male but their width and CSA are thicker than that of the male (p < 0.05).The mean Achilles tendon ATAP diameter in our study differs significantly from those of the Caucasian population. The mean AT diameters very with age, gender and BMI. The mean values found in our study differ significantly from the majority of other studies on Caucasian populations with respect to Achilles tendon AP thickness and CSA.

Key Words: Achilles tendon; Normogram; Musculo-skeletal; ultrasonography