Anatomy of the extensor tendons to the index finger
ABSTRACT An anatomic study was performed to better delineate the extensor tendons of the index finger. Seventy-two cadaver hands were dissected. Classically, a single slip of the extensor digitorum communis (EDC) and a single slip of the extensor indicis proprius (EIP) are said to run to the index finger. The EIP is said to be ulnar to the EDC at the level of the metacarpal head. In dissections in this study, the classic description was noted in 58 of the hands. Ten hands had a double slip of the EIP. Two hands had a double slip of the EDC running to the index. Two hands had a single slip of the EIP either volar or radial to the EDC at the level of the metacarpal head. Thirteen hands (19%) showed anatomic variants of the EIP and EDC tendons at the level of the metacarpal head, differing from the classic description. Additionally, two hands showed aberrant tendons. A knowledge of these variants when performing tendon repair or EIP transfer is necessary.
- SourceAvailable from: Daniel Casanova-Martinez
[Show abstract] [Hide abstract]
- "It was first described by Wood (1864). Since then, many studies confirm the presence of this muscle with a frequency from 0.5 to 4 % (De Vilhena 1933; Cauldwell et al. 1943; Godwin and Ellis 1992; Yoshida 1995; Gonzalez et al. 1996). The extensor indicis radialis (EIR) is also a supernumerary muscle. "
ABSTRACT: Anatomical variations of the fingers extensor tendons are not uncommon and have been described by several authors. Participation of intertendinous band of fascia in this kind of variation can change muscle functionality. However, this element is scarcely described in the literature. In this case report, we describe the finding of an accessory tendon located between the extensor digitorum communis muscle tendon, destined for the index finger, and the extensor pollicis longus tendon. In an anatomical analysis, we observed a connection between the radial portion of the accessory tendon and the ulnar portion of the extensor pollicis longus tendon by intertendinous fascia. This finding corresponds anatomically to the supernumerary muscle denominated extensor indicis radialis, but due to the fascial connections observed with the extensor pollicis longus, this muscle would behave functionally as a supernumerary muscle denominated extensor pollicis et indicis communis. This report suggests that participation of fascia in muscular variation in this anatomical segment is essential to establish the correct morpho-functional denomination of muscular variants.12/2012; 88(3). DOI:10.1007/s12565-012-0164-8
International Journal of Morphology 09/2012; 30(3):1071-1073. DOI:10.4067/S0717-95022012000300050 · 0.32 Impact Factor
- "Bingold (1964) said that the extensor indicis brevis may arise by a narrow aponeurosis from the wrist and insert by a slender tendon into the ulnar side of the extensor hood of the index. The extensor indicis muscle is widely utilized in surgeries of tendon transfer designed to restore a variety of finger movements (Gonzalez et al., Kitano et al., 1996; Batra et al.). It is utilized in reference to dysfunctions caused by functional loss of the abductor pollicis brevis, opponens pollicis muscles (Batra et al.), and extensor pollicis longus (Noorda et al.,1994). "
[Show abstract] [Hide abstract]
- "The anatomical distribution of the finger extensors was examined to understand their patterns of arrangement [14,15] and their structural variations . The extensor mechanism of the fingers is complex and has been discussed in its anatomy  and function . "
ABSTRACT: Our understanding of finger functionality associated with the specific muscle is mostly based on the functional anatomy, and the exact motion effect associated with an individual muscle is still unknown. The purpose of this study was to examine phalangeal joints motion of the index finger generated by each extrinsic muscle. Ten (6 female and 4 male) fresh-frozen cadaveric hands (age 55.2 +/- 5.6 years) were minimally dissected to establish baseball sutures at the musculotendinous junctions of the index finger extrinsic muscles. Each tendon was loaded to 10% of its force potential and the motion generated at the metacarpophalangeal (MCP), proximal interphalangeal (PIP), and distal interphalangeal (DIP) joints was simultaneously recorded using a marker-based motion capture system. The flexor digitorum profundus (FDP) generated average flexion of 19.7, 41.8, and 29.4 degrees at the MCP, PIP, and DIP joints, respectively. The flexor digitorum superficialis (FDS) generated average flexion of 24.8 and 47.9 degrees at the MCP and PIP joints, respectively, and no motion at the DIP joints. The extensor digitorum communis (EDC) and extensor indicis proprius (EIP) generated average extension of 18.3, 15.2, 4.0 degrees and 15.4, 13.2, 3.7 degrees at the MCP, PIP and DIP joints, respectively. The FDP generated simultaneous motion at the PIP and DIP joints. However, the motion generated by the FDP and FDS, at the MCP joint lagged the motion generated at the PIP joint. The EDC and EIP generated simultaneous motion at the MCP and PIP joints. The results of this study provide novel insights into the kinematic role of individual extrinsic muscles.Journal of Orthopaedic Surgery and Research 08/2008; 3:27. DOI:10.1186/1749-799X-3-27 · 1.39 Impact Factor