Axonotmesis

The axonotmesis injury is a traumatic injury of a peripheral nerve with transection of the axon. The myelin sheath of Schwann cells is likewise damaged, vital, though, that the continuity of the envelope structures of the nerve ( endoneurium, perineurium, epineurium ) is retained. Since the axon was interrupted, first a Wallerian degeneration takes place. The proximal axon stump forms a growth cone and grows along the Endoneuriumhülle obtained from. Upon successful regeneration, the degree of restoration of function is likely.

Demarcation

The axonotmesis is a moderate form of nerve injury. It is divided into the embossed by Herbert Seddon classification of neurapraxia of the lighter and the heavier still neurotmesis

Examination findings

Neuro Graphically, the excitability of the nerve distal to the lesion site is lost in the innervation of the nerves occur paresis, muscle atrophy and sensory disturbances, and autonomic functions are impaired.

Forecast

When axonotmesis in contrast to Neurapraxia degenerated axon beyond the injury site. The prognosis is still favorable, since the continuity of the surrounding connective tissue and basement membrane is preserved. Therefore, a substantial or even complete recovery of nerve function occur. The sprouting of new axons proceeds at a rate from 0.25 to 3 mm per day. The restitution therefore takes much longer than in a pure neurapraxia, - depending on the length of the damaged nerve section in the order of weeks to months. The regenerative capacity is maintained over years.