title: Extensor tendons and variations of the medial four digits of hand: a cadaveric study.
abstract: A total of 100 cadaveric limbs were dissected to study the anatomy of the forearm and hand extensor musculature. Four types of contributions to the index finger were found for the extensor indicis proprius (EIP), including one new type where the double tendons of the EIP inserts volar and radial to the extensor digitorum communis of the index finger (EDC-I). Four variant muscles were identified including the extensor medii proprius (EMP) (in five cadavers), extensor digitorum brevis manus (EDBM) (in one cadaver), extensor indicis et medii communis (EIMC) (in four cadavers) and extensor pollicis et indicis (EPI) (in four cadavers). The absence of the EIP in four cases was substituted by either the EIMC or the EPI. Two unpreviously published cases were found. In one hand, the variant EIMC was present along with the EPI. In another hand, both the EMP and the EDBM were present, and the EMP tendon inserted to the tendon of the EDBM. Awareness of the variations on the dorsum of the hand is essential for diagnosis, surgical planning and treatment of diseased hands.
authors.affiliation: Mahidol University International College, 999 Phutthamonthon 4 Road, Salaya, Nakhonpathom, 73170, Thailand.
authors.forename: Athikhun
authors.initials: A
authors.lastname: Suwannakhan
authors.affiliation: Department of Orthopaedics, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Rama VI Road, Ratchathewi, Bangkok, 10400, Thailand.
authors.forename: Tulyapruek
authors.initials: T
authors.lastname: Tawonsawatruk
authors.affiliation: Department of Anatomy, Faculty of Science, Mahidol University, Rama VI Road, Ratchathewi, Bangkok, 10400, Thailand. krai.mee@mahidol.ac.th.
authors.forename: Krai
authors.initials: K
authors.lastname: Meemon
mesh_terms: D063405:Anatomic Variation; D006225:Hand / Q000033:anatomy & histology*; D006801:Humans; D013710:Tendons / Q000033:anatomy & histology*
keywords: Anatomical variations; Extensor digitorum brevis manus; Extensor indicis et medii communis; Extensor medii proprius; Extensor pollicis et indicis; Extensor tendons