Surgical and Radiologic Anatomy

, Volume 38, Issue 9, pp 1083–1093 | Cite as

Extensor tendons and variations of the medial four digits of hand: a cadaveric study

  • Athikhun Suwannakhan
  • Tulyapruek Tawonsawatruk
  • Krai Meemon
Original Article


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.


Extensor tendons Anatomical variations Extensor medii proprius Extensor digitorum brevis manus Extensor indicis et medii communis Extensor pollicis et indicis 



We express our deepest respect to the body donors and their families.

Compliance with ethical standards

Conflict of interest

The authors declare no conflict of interest.


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Copyright information

© Springer-Verlag France 2016

Authors and Affiliations

  • Athikhun Suwannakhan
    • 1
  • Tulyapruek Tawonsawatruk
    • 2
  • Krai Meemon
    • 3
  1. 1.Mahidol University International CollegeNakhonpathomThailand
  2. 2.Department of Orthopaedics, Faculty of Medicine, Ramathibodi HospitalMahidol UniversityBangkokThailand
  3. 3.Department of Anatomy, Faculty of ScienceMahidol UniversityBangkokThailand

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