A prominent feature in this kind of sciatica is its great obstinacy and intractability. Another, equally marked, is the tendency to the development of spots around the foci of severest pain which are intensely and permanently tender, and the slightest pressure on which is sufficient to set up acute pain. This is a symptom much less developed, if developed at all, in the variety of sciatica which we first discussed. The places which are especially apt to present this phenomenon of tenderness are as follows: (1) A series, or line of points, representing the cutaneous emergence of the posterior branches, which reaches from the lower end of the sacrum up to the crista ilii; (2) a point opposite the emergence of the great and small sciatic nerves from the pelvis; (3) a point opposite the cutaneous emergence of the ascending branches of the small sciatic, which run up toward the crista ilii; (4) several points at the posterior aspect of the thigh, corresponding to the cutaneous emergence of the filets of the crural branch; (5) a fibular point, at the head of the fibula, corresponding to the division of the external popliteal; (6) an external malleolar, behind the outer ankle; (7) an internal malleolar. I have already mentioned that in sciatica the pain frequently spreads in a reflex manner to nerves which are connected, by their origin from the plexus, with the sciatic. It will be remembered, also, that I related cases in which the formation of tender points, in the course of the nerves thus secondarily affected, was even more distinct and remarkable than anywhere in the branches of the sciatic itself.