ACUTE INFLAMMATION OF THE KERATOGENOUS MEMBRANE 



047 



form and break, and not infrequently the plantar aponeurosis becomes 

 inflamed and, later, ruptured. 



(3) Septicaemia or general 

 infection sometimes results 

 from necrosis of the sensitive 

 lamina? or sole, especially 

 when the disease attacks the 

 os pedis. The pedal veins 

 offer little resistance to in- 

 fective material penetrating 

 their walls, and reaching 

 the general circulation. 

 Spinola drew attention to 

 the frequent connection be- 

 tween necrosis of the pedal 

 bone and attacks of septi- 

 caemia. The constant and 

 severe pain also causes the 

 patients to lie continually, 

 and, further, predisposes to 

 blood-poisoning. 



Causes. With the excep- 

 tion of laminitis, which will 

 later receive attention, acute fig. 559.— To illustrate the joints and deep 



inflammation of the sensitive 

 structures of the foot is due 

 to external injurious influ- 

 ences. Mechanical injuries, 

 like bruises, wounds by 

 driven or picked-up nails, 

 or separations of the wall 

 allow of irritants reaching the 

 sensitive parts directly ; in 

 other cases the injury is 

 thermal, but as the horny 

 box forms an excellent pro- 

 t e c t i o n against ordinary 

 changes in temperature, and 

 as burns from hot-fitting of 

 shoes are nowadays rare, 

 such cases are much less 

 frequent, Pricks in shoeing 



seated arteries, veins and nerves involved in 

 surgical injuries of the foot. Right fore foot, 

 seen from below, behind, and somewhat from 

 one side. The outer lateral cartilage is re- 

 moved, together with sufficient of the pedal 

 bone to render visible the vessels, &c, in its 

 interior. The nerves accompanying arteries /", 

 are shown too thick ; they should be less 

 than half as broad as figured, a, Digital artery ; 

 b, posterior suffraginal artery ; c, artery of 

 plantar cushion (cut through) : d, posterior 

 artery of coronary circle ; /, plantar artery, 

 which anastomoses with its fellow within the 

 pedal bone, and gives off twigs /', which 

 pass to the anterior surface of the pedal 

 bone, just above its lower edge ; g, twigs of 

 plantar artery supplying coffin joint ; E, deep 

 lateral layer of coronary plexus, clothing 

 inner surface of lateral cartilage ; F, divided 

 ends of superficial part of coronary plexus. 

 From these arise the digital vein (not shown) 

 H, plantar vein ; 4, posterior branch of digital 

 nerve accompanying vessels into pedal bone ; 

 5, twigs of posterior branch passing towards 

 sensitive laminse. 



