814 DISTENSION OF SYNOVIAL CAVITIES IN THE FORE LIMB. 



Treatment. Treatment is principally confined to blistering or 

 the use of the actual cautery, and though frequently ineffective, 

 sometimes decreases the lameness in two or three months. In young 

 horses rest alone may result in recovery. Where the growths arise 

 from the periosteum of the metacarpus the pointed cautery is of 

 use. Division of the median nerve sometimes removes the lameness ; 

 Moller so far cured several cases by neurectomy that the animals 

 became perfectly useful even for carriage work. 



IV.— DISTENSION OF ARTICULAR AND TENDINOUS SYNOVIAL 

 CAVITIES IN THE FORE LIMB. 



In the fore-limb several of the joint cavities and tendon sheaths 

 are so situate that distension is not visible externally. This is the 

 case in the shoulder and elbow. But in the knee, fetlock and pastern 

 joints, tendon sheaths and bursae, when distended with synovia, 

 form swellings or " galls." To prevent repetition the most important 

 will here be collectively dealt with. We may distinguish three 

 varieties : — (A) Distension of joints ; (B) Distension of the sheaths 

 of flexor tendons ; (C) Distension of the sheaths or bursa? of extensor 

 tendons. 



(A) Distension of articular synovial sacs. 



1. Of the knee. Though the construction of the knee is un- 

 favourable to the production of "galls," yet in working-horses 

 distension of the capsular ligament lying between the radius and 

 upper row of carpal bones is occasionally seen. This constitutes a 

 knee gall, and either appears as a roundish swelling, divided into 

 several parts by the extensor tendons on the front of the knee, or 

 occasionally as a tumour the size of a hen's egg, lying on the outer 

 surface of the limb, behind the radius and just over the pisiform 

 bone. 



2. Of the fetlock (articular wind galls). These consist of roundish 

 swellings between the metacarpus and suspensory ligament, caused 

 by distension of the synovial membrane of the fetlock-joint. They 

 often appear divided into two parts, are seldom larger than a duck's 

 egg, and extend forwards on either side of the fetlock. When the 

 foot is lifted they may disappear, but immediately weight is placed 

 on the limb they return. Hoffmann says they are particularly 

 noticeable when the fetlock is upright. 



3. Of the foot. These are of rare occurrence. They appear 

 above the coronary margin at the toe as tense, slightly painful 

 swellings ; their real nature is often unrecognised. Frick has seen 



