Angulated muscle fibers

What it means

Normal muscle fibers are polygonal-shaped in cross section, are multinucleated, and have minimal amounts of endomysial connective tissue. In contrast, angulated (also known as angular) muscle fibers have long and narrow vertices (corners) with sharp edges and a pointed tip.

Muscle fibers showing neurogenic atrophy are compressed by neighboring non-atrophic fibers and may show an angulated appearance on a transverse section. See Figure 3A in PMID:32529201.

Rare diseases that can present with this1

The range is how often this sign appears among people diagnosed with each disease — it is not a probability of having any of them. Many of these signs also occur in common, non-rare conditions. A sign on this page is a conversation to have with a clinician, not a conclusion.

Part of the broader category

Also called: Angular muscle fibers · Angular muscle fibres