158 



ABNORMAL CONDITION OF THE ANKLE-JOINT. 



oblique ligaments which pass before and be- 

 hind from the fibula to the tibia. The proper 

 interosseous membrane itself must be detached 

 from between the bones to allow the astragalus 

 to ascend along the outside of the tibia. While 

 the ligaments which connect the outer malleolus 

 to the tibia must be torn, those which unite it 

 to the foot remain entire, the deltoid or internal 

 lateral ligament must be completely torn across, 

 as well as the synovial sac of the articula- 

 tion ; nor should it be forgotten that the annu- 

 lar ligaments and strong fasciae at the lower 

 part of the leg, must, in so severe and ex- 

 tensive an injury, be lacerated; the tendons, 

 muscles, and other structures may escape injury, 

 the astragalus and outer malleolus are dragged 

 up (fg. 54, a, 6), their ascent being only limited 

 by the lower point of the upper fragment of 

 the fibula (c), which remains in its natural 

 relation to the tibia, except that it must be 

 somewhat approximated to it ; the lowest point 

 of the superior fragment of the broken fibula 

 rest upon the summit of the articular pulley of 

 the astragalus, as is well seen in a preparation 



B'eserved in the collection of St. Thomas's 

 ospital Museum, the delineation of which we 

 have borrowed from Sir A. Cooper's work. The 

 preservation of this specimen, which in our 

 mind is a true example of the complete dislo- 

 cation of the tibia inwards, and of the external 

 malleolus astragalus and foot upwards and 

 outwards, is a new proof of the truth of the 

 observation we have above made, that this 

 severe accident had not altogether escaped the 

 notice of English surgeons, although the 

 11 Annuaire" contains the first accurate account 

 of the external signs by which it may be recog- 

 nized in the living subject. 



Luxation of the tibia outwards, complicated 

 with simple fracture of one or both of the mal- 

 leoli. This, it is said, is one of the most dan- 

 gerous of the dislocations to which the ankle is 

 liable, for its production has been noticed to 

 be attended with greater violence, and to be 

 accompanied by more contusion of the integu- 

 ments, more laceration of ligaments, and greater 

 injury to bone, than we have occasion to ob- 

 serve in the production of the other luxations 

 of this joint. 



The astragalus in this accident is carried towards 

 and below the external malleolus(7zg. 55), whilst 

 the outer edge of the foot is turned downwards, 

 its inner edge upwards, and the sole inwards, 

 the tibial malleolus disappears, and is hidden 

 at the bottom of a retiring angle formed by the 

 inner side of the leg and foot, and the peroneal 

 malleolus forms, with the astragalus, a salient 

 angle rounded off on the outside. Looking 

 only to the change of form, situation, and rela- 

 tive position of the leg and foot, we might sup- 

 pose the case one of congenital club-foot.* The 

 luxation of the tibia outwards, with inversion 

 of the sole of the foot, is one of the most rare 

 and most difficult cases to explain. Its pro- 

 duction must be the result, we suppose, of co- 

 incidences rare and unusual. There may be a 

 certain obliquity in the line of direction of the 



* Dupuytren, Annuaire. 



Fig. 55. 



Fig. 56. 



Luxation outwards of the Dissection of the luxa- 

 tibia and fibula with ob- tion outwards (Museum 

 lique fracture of the tibia. of St. Thomas's Hospi- 

 tal}. [Fty.55.] 



fracture coinciding with a considerable degree 

 of resistance in the lower fragment of the fibula : 

 thus, if we can suppose that a fracture shall 

 traverse the tibia obliquely from above down- 

 wards, and from within outwards, so that the 

 point of the upper fragment be directed down- 

 wards and outwards, and the lower fragment point 

 upwards and inwards, and if to this obliquity 

 we suppose added a certain resistance on the 

 side of the lower fragment of the fibula, it is 

 plain that the foot being unable to turn out- 

 wards, must be carried inwards by the action 

 of the muscles, and with this inversion, &c. 

 some little shortening of the limb, at least 

 when measured on its inner side, may be ex- 

 pected. 



If this accident be neglected, the cure which 

 nature attempts is very imperfect, the ankle-joint 

 becomes stiff and rigid (fg. 56), the interval be- 

 tween the internal and external malleolus is 

 much increased^ the latter presses heavily 

 against the integuments, which, when the limb 

 is much exercised, have a strong tendency to 

 inflame and suppurate, the outer edge of the 

 foot throughout its whole line presses the 

 ground, whether the patient be standing or 

 walking, while the inner edge is somewhat 

 elevated and curved inwards. In the dissec- 

 tion of this accident, it will be found that the 



