Anatomical Investigation of the Flexor Retinaculum Covering the Tarsal Tunnel in Formaldehyde-Fixed Cadavers

Aim: The flexor retinaculum lies between the medial malleolus of the tibia and the medial process of the calcaneus. It converts grooves on the tibia and calcaneus into the tarsal tunnel. The aim of this study was to analyze the morphometry, the course, and the shape of the flexor retinaculum covering the tarsal tunnel in formaldehyde-fixed cadavers. Material and Methods: Six lower extremities of four formaldehyde-fixed cadavers (four right sides, and 2 left sides) were examined to evaluate the morphometry of the flexor retinaculum. The cadavers were two females and two males with an age range of 60-89 years. A digital caliper (150 mm) and a light microscope were used for measuring parameters. The central length, proximal, midpoint, and distal width, thickness, course, and shape of the flexor retinaculum were examined in this study. Results: The mean central length of the flexor retinaculum was found 42.26±5.18 mm. The mean proximal, midpoint, and distal width of the flexor retinaculum were 29.29±7.29 mm, 29.92±3.66 mm, and 29.76±8.13 mm, respectively. The mean of the thickness was measured at 234.94 µm. The flexor retinaculum coursed vertically in four extremities and coursed obliquely in two extremities. The shape of the retinaculum was triangular in five extremities and quadrangular in only one extremity. Conclusion: The morphometric data obtained from this study can help surgeons during the operations of the tarsal tunnel syndrome. To our knowledge, the width and course of the flexor retinaculum were examined for the first time in this study. Amaç: Retinaculum flexorum, tibia'nın malleolus medialis'i ile calcaneus'un processus medialis'i arasında uzanır. Retinaculum flexorum, tibia ve calcaneus üzerindeki olukları tarsal tünele dönüştürür. Bu çalışmanın amacı, formaldehit fikse kadavralarda tarsal tüneli kaplayan retinaculum flexorum’un morfometrisini, seyrini ve şeklini incelemektir. Gereç ve Yöntemler: Dört formaldehit fikse kadavraya ait olan altı adet alt ekstremite (dört sağ taraf ve iki sol taraf), retinaculum flexorum morfometrisini değerlendirmek için incelendi. Yaş aralığı 60-89 yıl arasında olan kadavraların ikisi kadın ve ikisi ise erkek idi. Parametrelerin ölçümü için bir dijital kumpas (150 mm) ve bir ışık mikroskobu kullanıldı. Bu çalışmada retinaculum flexorum’un santral uzunluğu, proksimal, orta nokta ve distal genişliği ile kalınlığı, seyri ve şekli incelendi. Bulgular: Retinaculum flexorum’un ortalama santral uzunluğu 42,26±5,18 mm ola