[Typical and atypical forms of neuralgic amyotrophy of the shoulder: 86 cases].

Eighty-six cases of neuralgic shoulder amyotrophy are reported. Among these, 67 cases were concordant with the usual semeiological description. The other cases were atypical in their anatomical distribution (extensive or restricted to peripheral nerve rami), in their course (chronic or recurrent or alternating from one side to the other) and in their cause, notably familial forms. The continuum existing between these variants is most probably due to an immuno-allergic mechanism.