Anat Biol Anthropol.  2023 Mar;36(1):9-15. 10.11637/aba.2023.36.1.9.

Morphologic Analysis and Classification in Insertion of the Fibularis Tertius Tendon: A Cadaveric Study

• Kwon H
• Cho J
• Choi Y
• Park K
• Lee M
• Kim D
• Park SB
• Park J

• KMID: 2541220
• DOI: http://doi.org/10.11637/aba.2023.36.1.9

Abstract

The fibularis tertius muscle originates on the medial surface of the fibula and attaches to the proximal portion of the fifth metatarsal bone. The aim of this study is to provide an anatomical basis for the role of the fibularis tertius tendon in the mechanism of fifth metatarsal avulsion fracture by classifying the shape and location of the fibularis tertius tendon in Korean cadavers. For this study, 89 feet were dissected using formalin-fixed Korean cadavers. There were 61 male and 28 female, and the average at death age was 78.79±11.00 years. Ercikti’s method was applied for classification according to the shape of the insertion in the fibularis tertius tendon, and the width of the footprint of insertion was measured additionally. As a result, the fibularis tertius tendon was type 1 (one-branch) in 56% and type 2 (two-branch) in 44%. Tendons were absent in 7 feet (7.9%), type 1a in 2 feet (2.2%), type 1b in 26 feet (29.2%), type 1c had 16 feet (18.0%), type 1d had 2 feet (2.2%), type 2a had 35 feet (39.3%), and type 2b) was 1 feet (1.1%). The width of the fibularis tertius tendon attachment site was 15.50±2.12 mm in types 1a, 19.23± 3.91 mm in types 1b, 17.43±3.91 mm in types 1c, 12.22±7.07 mm in types 1d, 20.42±5.12 mm in type 2a, 20.00 mm in type 2b. There was no difference in the width of the fibularis tertius tendon according to gender and side. In conclusion, the shape of the fibularis tertius tendon contact point would be able to load the proximal attachment part of the fifth metatarsal bone. Based on this, we suggest the need for a schematic study or biomechanical study of the fibularis tertius tendon in relation to the fifth metatarsal avulsion fracture.

Keyword

Korean cadaver; Ankle; 5^th metatarsal bone; Fibularis tertius tendon; Avulsion fracture