It is known that soft tissue (skin, muscle, etc.) grafts to severely damaged or transected nerves can prevent or alleviate aberrant growth leading to neuropathic pain. We wanted to further understand the mechanism of reinnervation, especially across nerve and tissue types that are not thought to be inherently compatible.

The finding of cutaneous neurons contacting and changing NMJs, as well as finding rare muscle sensory sites, is fascinating but questions remain about the fate of the remainder of the axons as the reinnervation is much denser than the original muscle tissue. 

In our images, multiple small cutaneous neurons are seen contacting each neuromuscular junction, which are typically singly innervated by alpha motor neurons. The reinnervating neurons are clearly changing and thinning the morphology of the neuromuscular junction (NMJ) yet not seeming to form functional synaptic connections (as demonstrated by the lack of presynaptic vesicle/synaptophysin colocalization).