DISPLACEMENT OF THE BICEPS EEMORLS MUSCLE. 
681 
after falls lame again. When the muscle becomes fixed in the abnormal 
position it appears tense, and its outline more distinct, whilst a depression 
appears in front of the trochanter. 
Course. Spontaneous recovery is never permanent ; and unless 
operation be resorted to, habitual luxation results, i.e., the lameness 
continually recurs, or becomes lasting. 
Treatment. Myotomy is the only means of cure. The operation is 
usually carried out with a free incision as follows :—By drawing the 
sound limb forward weight is thrown on its neighbour, and a nearly 
perpendicular incision, about 2 inches in length, is made through the 
skin 2 inches below and just in front of the trochanter, in the direction 
of the muscle. Beginning at its anterior border, the muscle is then 
divided from subjacent tissues by using the fingers or the handle of a 
scalpel. It is next lifted, a director thrust under it transversely, and it 
is divided with a scalpel from within outwards. With proper treatment 
the wound heals in sixteen to eighteen days. Hertwig has shown that 
the section might be made subcutaneously. Healing would doubtless be 
more rapid by observing antiseptic precautions. 
In the horse, the muscle does not pass over the upper trochanter, but back¬ 
wards between it and the ischium, becomes attached by a tendon to the upper 
part of the ischial tuberosity, which it partly covers, and then blends with 
the middle and short abductor. The muscle, therefore, during its course, 
describes a curve, and one portion of it passes over the ischial tuberosity, 
to which it is attached by means of a tendon . 
In fractures of the ischium, the tuber ischii may be displaced by the pull of 
this muscle, resulting in deformity of the buttock ; the symptoms are similar 
to those in the above-described disease of cattle. Moller saw two cases of 
this kind. 
A ten year old grey gelding had fallen in front of the carriage and was 
lame, but in the stable showed nothing unusual. A careful examination of 
the pelvis proved, however, that the left buttock was abnormally flat at the 
height of the tuber ischii. Seen from the side, the right buttock projected 
considerably further than the left, the flattening, which was about 1 to 2 inches 
in size, was most marked over the tuber ischii, and lost itself above and 
below, as well as externally and internally. The right tuberosity could be 
distinctly felt, but the left was indistinguishable; a soft mass of muscle 
occupied its position, and the bone could only be felt in the depths. Around 
the trochanter the muscles of the quarter were slightly prominent, so that 
when seen from behind, the left quarter appeared broader than the right. 
Lower down the middle line of the perineum was thrust about an inch to 
the left. 
At a walking pace there was moderate supporting leg lameness of the left 
limb, which was abducted both when loaded and when freely swinging. By 
placing the hand on the quarter, close behind the upper trochanter, during 
movement, it was possible at the moment the limb was relieved of weight to 
detect a sensation as though a cord moved from behind forwards, and then 
immediately glided back again. Careful observation detected this jerking 
movement of the biceps femoris muscle, over a region extending from a point 
about 4 inches above and to the side of the upper trochanter, as far as the 
