Fig 4. Classification of histological characteristics of nerves in limb stumps after amputation.

Normal nerve (N0i: longitudinal and N0ii: transversal section), degenerating axons (N1), axonal sprouts (N2i: at the end of damaged fascicles, arrows show elongated structures corresponding to axonal fibers and N2ii: at distal area, arrows show isolated axons appearing as donut ring-like structures), unorganized axons bundled in connective tissue (N3), unorganized axon ramifications in muscle (N4), neuroma—highly unorganized axons in tissue (N5). Scale bar = 100μm.