476 VETERINARY SURGICAL OPERATIONS 



neously sliding forward the point is at once forced into the 

 frog. At first it only enters the horn or is only wedged into 

 the lacuna, but with each successive step it is driven inward 

 more and more until it meets with resistance that causes the 

 protruding part to bend against the foot. If the nail is 

 pointed and favorably directed it may be driven inward step 

 after step until the head reaches the level of the shoe. Some- 

 times in this manner a long nail or spike may completely 

 transfix the foot from the side of the frog to the pit between 

 the heels, following the perforans tendon on its upward 

 course. By the simple application of a smooth cover to the 

 solar surface nails are intercepted from attaching themselves 

 to the frog as the point is tipped upward by treading upon 

 the nail head, and thus penetration is successfully prevented. 

 It is only the nail fixed point upward upon the street that 

 penetrates protective pads and since such nails are rare as 

 compared with those lying flat, street-nail punctures are al- 

 most entirely eliminated by them. 



The economy from protecting pads can hardly be over- 

 estimated in large establishments, in view of the annual loss 

 from this single disabling and often fatal accident. 



TREATMENT.— The horse-shoer's method, which con- 

 sists of paring the hoof thin and excavating the horn around 

 the perforation and then submitting the wound to a thor- 

 ough cauterization with hydrochloric acid, is commendable 

 because of the certainty with which the inoculated microbes 

 are destroyed. It is only where the caustic does not reach 

 the depth of the tract, or where the inflammation has already 

 advanced into the inaccessible surroundings that such treat- 

 ment fails or becomes more harmful than beneficial. This 

 "first aid" can in no light be discredited if immediately em- 

 ployed, and especially if the penetration is superficial. On 

 the other hand, when the tract is. a deep one or the puncture 

 is of several days' duration, the cauterization may do harm 

 by producing an impervious eschar that will subsequently 

 obstruct the drainage. 



The veterinarian usually arrives upon the scene when 

 the inflammation is already well advanced, the claudication 

 is accentuating, and the patient is beginning to show sys- 

 temic invasion of the microbic products. At this stage the 

 following routine is recommended : 



RESTRAINT.— The operation may be performed in the 

 stable or at the horse-shoer's in the standing position. In 

 the restive horse cocainization of the plantars is helpful. 



