i ; 
t 
ABNORMAL CONDITIONS OF THE KNEE-JOINT. 
which had been broken exceeded by about six 
times the same diameter of that of the opposite 
side. The fracture did not represent a straight 
nsverse line, but was somewhat undulated. 
it the two extremities of the line of junction of 
the fracture it was quite evident that the union 
of the broken bone was immediate, and by the 
tervention of a true bony callus. Lallement 
esented Boyer with the patella thus solidly 
ited, and he has given an engraving of it in 
his valuable work. 
Inthe collection of Dr. William Hunter, there 
sa well-marked instance of bony union of a 
transverse fracture of the patella, and other 
xamples have been seen in the dead subject 
by Mr. Wilson. In Sir Charles Bell’s museum 
were likewise similar specimens, one or two of 
which ae now in the Museum of University 
Vollege. 
_ Dislocations of the femur from the tibia at 
the knee-joint.—The articular surfaces of the 
_ head of the tibia for the reception of the femoral 
condyles are very superficial ; and although the 
Semilunar cartilages are superadded to them 
_ for the reception of the condyles of the femur, 
they have no direct tendency to resist luxations 
of the femur at the knee-joint. On the other 
_ hand it is to be recollected that the surfaces by 
hich the tibia and femur are articulated 
together are broad, and that the number and 
Strength of the ligaments which unite these 
_ bones is considerable. The solidity of the arti- 
i ulation is further augmented by numerous and 
‘powerful tendons which surround the joint. 
_ Although therefore the knee-joint from its situa- 
_tion and functions must be subjected to nume- 
Tous injuries, dislocations are very seldom wit- 
_ nessed as the result of accident. Dislocations, 
however, occur in four different directions ; two 
of them are incomplete and lateral while the 
‘others are perfect luxations, the femur being 
thrown either backwards or forwards. The 
Tateral luxations are the rarest. 
__._ The lower extremity of the femur is now and 
_ then dislocated backwards: the signs of the 
accident are the following. The thigh-bone is 
_ somewhat displaced to the side as well as back- 
_ wards, and the tibia is advanced before the 
_ condyles of the femur. The lower dislocated 
| extremity of the os femoris makes such pressure 
on the pean artery as to prevent the pulsa- 
tion of the anterior tibial artery on the foot. 
The patella and tibia are drawn by the rectus 
_ muscle forwards; such, Sir A. Cooper tells us, 
_ are the appearances the knee-joint presented in 
_ aman brought into St. George’s Hospital in the 
_ year 1802. The limb in this case was easily 
_ reduced by extending the thigh from above the 
__ knee, and by drawing the leg from the thigh and 
inclining the tibia a little backwards. As soon 
_ as it was reduced, the popliteal artery ceased to 
__ be compressed, and the pulsation in the anterior 
_ tibial artery was restored. We will quote the 
| following abstract. of a case of dislocation of the 
: 4 lower extremity of the femur backwards ;+ the 
‘ 
y 
* Prof. Cooper. 
+ London Medical Gazette, May 14, 1836, given 
| by Mr. Thomas Brittan, House Surgeon, Chester 
| Infirmary. 
: 
W 
: 
71 
subject of the accident, besides other injuries, 
was brought into the Chester Infirmary with a 
very complete dislocation of the lower extremity 
of the femur backwards. The whole limb was 
shortened four or five inches, and the condyles 
of the femur could be felt plainly among the 
muscles of the calf of the leg, while the tibia 
was in advance of the femur and drawn up- 
wards on the anterior part of this bone. The 
leg and foot were swollen and cold; all cireu- 
lation below the knee was stopped; there were 
no marks of external contusion. It appears 
that although the pulleys were used to reduce 
the luxation, it was easily effected by gradual 
extension of the limb. It became necessary 
after about five weeks had passed from the time 
of the accident, to amputate the limb in conse- 
quence of an extensive abscess which formed in 
the ham and calf of the leg. Upon examining 
the amputated limb, jit was found that the pop- 
liteal abscess was wy extensive and commu- 
nicated with the knee-joint. On tracing the 
course of the artery, which had been previously 
injected, it was found to be obliterated from 
just below the point where it gives off the 
superior articular artery, exactly to its bifurcation 
into the anterior and posterior tibial arteries. 
The nerve also for this distance was slightly 
enlarged and firmer than natural, having a cord- 
like feel; the whole being so closely connected 
by dense cellular tissue as to be scarcely sepa- 
rable. The attachments of the muscles were all 
perfect and did not appear to have been lace- 
rated. With respect to the joint the lateral 
ligaments on both sides were perfect; the ante- 
rior crucial ligament had been absorbed, but 
the posterior crucial ligament and the posterior 
ligament of Winslow were united into one 
band ; the synovial membrane was healthy or 
but very little altered; the semilunar cartilages, 
as well as those on the ends of the bones, were 
sound; there was no fluid in the joint. 
Case of dislocation of the femur backwards 
from the tibia—Sir A. Cooper remarks that 
cases of dislocation of the knee-joint are so 
rare that every instance of this accident is 
worthy of recita!. He adduces the following 
example from the experience of Mr. Too- 
good, of Bridgewater. Francis Newton, a 
strong athletic man thirty years old, fell from 
the fore part of a waggon, and was dragged a 
great distance betore he was disentangled from 
the framework of the shafts. In two hours 
after the accident the left knee was observed to 
be very much swollen; the os femoris was dis- 
located backwards, and its lower extremity 
occupied the upper part of the calf of the leg, 
the internal condyle of the femur being nearly 
through the skin; the tibia, fibula; and patella 
were driven up in front of the thigh. The 
appearances of the limb were so dreadful that 
Mr. Toogood despaired at first sight of being 
able to reduce it, but to his surprise the reduc- 
tion was easy. The limb was placed in splints; 
the strictest antiphlogistic treatment with rest 
was prescribed ; the symptoms were mild, and 
he suffered little from pain or inflammation. 
Malgaigne, in a letter to Velpeau in the Ar- 
chives Medicales, June 1837, upon the subject 
