PERONEAL TENOTOMY 155 



groove on the external malleolus, and which terminates inferiorly almost 

 immediately after the tendon leaves the most inferior of the annular 

 bands. The sheath facilitates the gliding of the tendon through the 

 groove in the malleolus and the channel in the external lateral ligament. 

 In cases of distension of this sheath an enlargement usually makes its 

 appearance at its inferior extremity. It is peculiar inasmuch as it is 

 not elongated from above to below, as would naturally be expected, but 

 assumes a rounded form, and may attain the size of a tennis ball. The 

 usual symptoms are presented according to whether the swelling is 

 recent or chronic, but in either case there is little, if any, interference 

 with the action of the limb. If it is decided to treat, the treatment 

 which has already been given for enlarged bursas should be adopted. 

 It may be stated that there is little danger in operating surgically in 

 cases of distension of this sheath. 



PERONEAL TENOTOMY 



Boccar and others attributed the peculiar snatchy action in stringhalt 

 to defective action of the peroneus muscle, and hence introduced the 

 operation of peroneal tenotomy in the treatment of that affection. 



Stringhalt is dealt with in our chapter on nerves, but although our 

 knowledge of the pathology of this disease is so indefinite, and on this 

 account so many different causes are attributed to it, there is no doubt 

 but that in some cases considerable improvement in action is brought about 

 by section of the peroneal tendon. The author has frequently performed 

 the operation in the treatment of very pronounced cases, and whilst 

 admitting that in by far the greater number no improvement was 

 manifest, in a few cases the result was most satisfactory. It may be, as 

 Macqueen states, that the operation is only effective in bringing about 

 an improvement in those cases which present an abnormal degree of 

 abduction. 



