Anatomical Classification of Plantaris Tendon according to Shape and Location of Insertion in Korean

Abstract

The plantaris muscle is a small muscle with a short belly and long thin tendon that forms part of the posterior superficial compartment of the calf. The purpose of this study was to classify the insertion type of plantaris tendon of Korean population, to measure anthropological characteristics by measuring the width and thickness, and to obtain clinically applicable anatomical basis data. The dissection was performed on 68 lower limbs (34 right, 34 left) fixed in formalin mixture. The types of insertion of plantaris tendon was classified according to the area and location of insertion into calcaneal tuberosity and calcaneal bone. In this study, all five types were identified. 25 limbs (36.8%) were classified into type 1, 8 limbs (11.8%) into types 2 and 3 respectively, 5 limbs (7.4%) into type 4, 18 lower extremities (26.5%) into type 5. The plantaris tendon was found to be absent in 4 lower limbs (5.9%). No differences in body side or gender were found in the insertion type of plantaris tendon. The thickness of the plantaris tendon was 0.72±0.27 mm for males and 0.59±0.18 mm for females, and males were thicker than females (p = 0.029). However, there was no difference between the two genders in the width of the plantaris tendon. In conclusion, this study not only examined the morphological characteristics of plantaris tendon in Korean population, but also presented basic anatomical data that doctors can apply to clinical practice.