REGION OF THE WRIST. 347 



Ulnar Incision. From a point 2.5 cm. (i in.) above the styloid process of 

 the ulna toward its palmar surface, downward to the base of the fifth metacarpal 

 bone (Fig. 358). 



When making the radial incision, branches of the radial nerve may be seen in the 

 lower part of the incision and should if possible be avoided. In making the ulnar 

 incision a cutaneous branch of the ulnar nerve should be avoided as it verges toward 

 the dorsal surface below the styloid process. 



The extensor indicis tendon is pulled aside and the extensor carpi radialis 

 brevior beneath detached with the periosteum from the base of the third metacarpal 

 bone. The incision is then extended higher up the wrist, care being taken not to in- 

 jure the tendon of the extensor longus pollicis at the posterior radial tubercle. The 

 periosteum is to be detached over the lower end of the radius, the radiocarpal joint 

 opened, and the carpal bones removed one after another. The pisiform bone, 

 unciform process, and trapezium are left when possible. In removing the unciform 

 process the deep branch of the ulnar nerve should be avoided. If the trapezium is 

 removed care must be taken not to wound the radial artery as it goes over the bone 

 to dip between the first and second metacarpal bones, and also to avoid the flexor 

 carpi radialis tendon as it crosses to the inner side of the ridge of the trapezium on 

 its palmar surface. 



The articular ends of the ulna and radius may be removed with a small saw if 

 necessary. As Jacobson says, this operation is a tedious and difficult one, and we 

 might add that it is liable to be an inefficient one, owing to the inability to remove 

 all of the diseased tissue. 



Operations of Studsgaard and Mynter. Studsgaard of Copenhagen in 

 1891 (" Hospitalstidenden," Jan. 7, 1891) suggested, and Herman Mynter of Buf- 

 falo ( Transactions of the American Orthopedic Association, 1894, v l- vn *> P- 2 53) 

 carried out the method of splitting the hand on the dorsum from the web between 

 the second and third fingers to the lower edge of the radius, and on the palmar 

 surface to the base of the thenar eminence. 



Dr. Wm. J. Taylor {Annals of Surgery, vol. xxii, 1900, p. 360) modified the 

 operation by employing only the dorsal incision. This operation gives full access 

 and exposure to the parts, and all disease can most readily be recognized and re- 

 moved with the scissors or other instruments. It is probably the best method of 

 exposure and operation when simple incision and curetting does not suffice. 



AMPUTATION THROUGH THE WRIST-JOINT. 



When it is possible to do so the interarticular fibrocartilage over the lower end 

 of the ulna is not to be interfered with. The lower radio-ulnar joint is therefore not 

 injured and the movements of pronation and supination are preserved. 



The styloid process of the radius is i cm. below that of the ulna. It is directly 

 on the outer side of the radius, while the styloid process of the ulna is toward the 

 posterior surface. 



On account of the skin of the palm being thick and well adapted for pressure a 

 long palmar flap is preferred. 



Incision. On account of retraction, the knife is entered i cm. (|^ in.) below 

 the radial styloid process the thumb being abducted to render the tissues tense, and, 

 if the left hand is being operated on, the knife is carried straight down well on the 

 thenar prominence. It is then curved abruptly across the palm on a level almost or 

 quite as low as the web of the thumb. It is continued to the ulnar side and up 

 to within I cm. of the styloid process of the ulna. The flap should be an almost 

 square one with rounded ends. The incision goes down to but does not divide the 

 flexor tendons (Fig. 359.) 



This flap, embracing the palmar fascia and part of the thenar and hypothenar 

 muscles, is at once raised from the flexor tendons, care being taken not to catch the 

 knife on the unciform and pisiform bones. 



The hand is now pronated and a dorsal flap 2.5 cm. (i in.) long is cut. As the 

 skin is loose and elastic this length is needed to provide against retraction. 



