

Dislocation of Thumb 



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careful examination and measurement, however, quickly clear up any 

 doubt. 



The most important injury of the thumb is that in which the first 

 phalanx is dislocated backwards, the end of the metacarpal bone 

 slipping forwards between the heads of insertion of the flexor brevis 

 pollicis with its allied muscles, the abductor pollicis with the outer 



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head, and the adductor with the inner. The result is that the 

 more the surgeon pulls on the phalanges, the narrower the interval 

 between the heads of the flexor brevis becomes, the more tense are 

 those heads, and the firmer the grasp of the neck of the metacarpal 

 bone. Before attempting reduction, therefore, the metacarpal bone 

 should be thrust towards the palm, so as to slacken to the utmost the 



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