Snapping Pes Syndrome Caused by the Gracilis Tendon: Successful Selective Surgery with Specific Diagnosis by Ultrasonography. - Akagawa, Manabu; Kimura, Yoshiaki; Saito, Hidetomo; Kijima, Hiroaki; Saito, Kimio; Segawa, Toyohito; Wakabayashi, Ikuko; Kashiwagura, Takeshi; Miyakoshi, Naohisa; Shimada, Yoichi (Case Reports in Orthopedics, 2020)