On incising the anterior closed space, besides the external signs of swelling, redness and tenderness together with a point of entry and throbbing pain (which is worse at night), one finds edema and swelling of the perpendicular connective tissue fibers. Pus is interspersed between the fibers, and the tuft of the phalanx shows evidences of softening. In cases of advanced infection, the tuft and part of the shaft of the phalanx are destroyed, and in cases in which the infection has reached a late stage, the entire phalanx is necrotic. In the latter type of case, an attempt should be made to preserve the base of the phalanx since it possesses regenerative powers.
Early sections of the distal portion of the phalanx reveal polymorphonuclear exudation into the marrow. Roentgen examination at this stage does not reveal any evidences of the destruction of bone. This is natural, because osteomyelitis is seen