Investig Magn Reson Imaging.  2016 Jun;20(2):123-126. 10.13104/imri.2016.20.2.123.

The MRI Findings of Flexor Digitorum Accessorius Longus Muscle: a Case Report

• Shin JH
• Shim JC
• Lee KE
• Kim HK
• Lee GJ
• Suh JH

• KMID: 2327425
• DOI: http://doi.org/10.13104/imri.2016.20.2.123

Abstract

The flexor digitorum accessorius longus (FDAL) is the most common accessory muscle found in the posterior compartment of the ankle area. The accessory muscle in this area such as the FDAL may be incidentally identified on magnetic resonance images (MRI). There are some case reports about the FDAL in cadaver researches. However, the MRI findings about the FDAL have been reported in a few cases. In this paper, we report a case of the FDAL incidentally identified on MRI with review of the literature about the FDAL.

Keyword

Flexor digitorum accessorius longus; Anatomical variation; Accessory muscle; Magnetic Resonance Imaging

MeSH Terms

Ankle
Cadaver
Magnetic Resonance Imaging*

Figure

• 

  Fig. 1 MR images of the left ankle. (a) Axial proton density-weighted image (TR/TE, 3000/44) shows the flexor digitorum accessorius longus (FDAL) muscle (arrow) originating from the posterior muscular compartment. (b) Axial proton density-weighted image (TR/TE, 3000/44) shows the FDAL muscle (arrow) passing lateral to neurovascular bundle and posterior to flexor hallucis longus (FHL) tendon (arrowhead) in tarsal tunnel. (c) Coronal proton density-weighted image (TR/TE, 3000/44) shows the FDAL muscle (arrow) descends obliquely along the ankle region. (d) Sagittal proton density-weighted image (TR/TE, 3000/44) shows the FDAL (arrow) inserting on the quadratus plantae muscle (arrowhead).

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