A cadaveric study of the Arcade of Frohse

Context: Arcade of Frohse (AF) is the free aponeurotic proximal edge of the superficial part of supinatormuscle. The posterior interosseous nerve (PIN) passes deep to it before entering supinator muscle. AF isthe most frequent cause of PIN compression and radial tunnel syndrome. Knowledge of anatomy of AF isessential for surgeons while performing PIN decompression surgery.Aim: To study the morphology and morphometry of Arcade of Frohse.Settings and Design: The descriptive study was carried out in the department of anatomy on the cadaversthat were routinely used for undergraduate education.Materials and Methods: The AF was dissected out and studied in 60 upper limbs of adult human cadavers.Its shape and consistency were studied. The length, width and thickness of the arcade was measured usingVernier’s callipers.Statistical Analysis Used: All measurements were recorded in mm and analysed using range, mean andstandard deviation.Results: The shape of the arcade was semicircular in 13%, semi-oval in 17% and oblique elongated in70%. The arcade was tendinous in 80% and membranous in 20%. The mean length, width and thickness ofAF are respectively 13.1+ 2.64 mm, 10.21+2.57 mm and 0.43+0.37 mm respectively.Conclusions: Three types of morphology of AF have been identified based on the shape of the arcade.Tendinous AF was four times commoner than the membranous. The arcade had an average length, widthand thickness of 13 mm, 10 mm and 0.4 mm respectively.Keywords: Arcade of Frohse, Posterior interosseous nerve, Radial tunnel syndrome.