I 
INFLAMMATION OF BURSA OF BICEPS MUSCLE. 507 
exostoses; the synovial membrane was thickened, and to some extent 
ossified; in one case synostosis had even occurred. 
Prognosis. The variations in the pathological conditions are so great 
that no fixed principles can be laid down either for prognosis or treat¬ 
ment. The degree of local change, the severity of the lameness and 
the time it has existed, form the chief indications. Excessive muscular 
atrophy and obstinate lameness are always grave. The symptoms are 
equally varied (compare with “ Shoulder Lameness”)- 
iy.—INFLAMMATION OF THE BURSA OF THE BICEPS, 
FLEXOR BRACHII OR CORACO RADIALIS MUSCLE 
(BURSITIS INTERTUBERCULARIS). 
Anatomy. During flexion and extension of the shoulder-joint the tendon 
of the flexor brachii glides over the bicipital groove of the humerus, which is 
covered with cartilage, and forms one of the boundaries of an extensive bursa 
(bursa intertubercularis). The bursa extends from the periphery of the 
cartilage-covered tuberosities, over the tendon, clothes a portion of its 
surface, then its sides, and finally its under face. The sides of the bursa 
are covered by the lower points of insertion of the supraspinatus muscle, and 
its cavity is divided from the capsule of the shoulder-joint by a mass of fat. 
In swine and carnivora, the bursa is continuous with the shoulder-joint. Its 
position is nearer the central line of the body than in the horse. 
In horses, the extensive intertubercular bursa is sometimes the seat 
of acute or chronic inflammation, in which the biceps tendon shares, 
and which almost always results from severe bruises, such as are caused 
by collisions when the shoulder is struck and the biceps receives the 
full shock. Wounding of the bursa may be followed by acute septic 
inflammation. Runaway horses frequently suffer. 
A chronic bursitis (which may be bilateral) is produced in tramway 
and omnibus horses by continuous rapid driving. 
As in acute inflammation of other tendon sheaths, serous and fibrous 
exudates occur ; in affected wounds and metastatic diseases purulent 
inflammation of the sheath of the tendon may set it. Dieterichs saw 
symptoms of acute inflammation, hypersemia, and exudation in horses 
which had shortly before fallen ill. Necrosis of the bursa in the horse 
was seen by Moller. The tendon was partially necrotic, the gliding 
surface on the humerus deprived of cartilage and eroded. 
Chronic bursitis produces abrasion of cartilage, formation of exostoses 
on the humerus, and ossification of the biceps. Williams and Dieterichs 
found the muscle almost entirely ossified, though in Dieterichs’s case the 
biceps had become adherent to*the humerus. The gliding surface of 
the biceps is frequently roughened from friction against the roughened 
