PERIPHERAL PALSY. 361 



teristic forms of cerebral and spinal palsy are hemiplegia and paraple- 

 gia, while a palsy limited to the range of influence of some particular 

 nerve is an almost pathognomonic symptom of peripheral paralysis. 

 It is only as a symptom of incipient sclerosis, and in rare instances, 

 that the power of volition is suspended in single nerves owing to dis- 

 ease of the brain, or that the connection between the spinal marrow 

 and any particular nerve is broken. The converse of this proposition 

 is not true, however, as there are many peripheral palsies which in- 

 volve large numbers of nerves. Even in such cases, however, the 

 mode of extension of the malady often reveals its source. When a 

 tumor of the brain causes palsy of the region supplied by the various 

 cerebral nerves, the palsy does not arise in all of the nerves simulta- 

 neously, but extends gradually from one to another as the tumor 

 grows. I shall mention one case observed in the Greifswalder clinic, 

 as a striking example of how extension of the palsy may be of great 

 importance as a means of distinction between spinal and peripheral 

 paralysis due to .caries of the vertebrae. The patient suffered from 

 caries of the vertebrae, and his upper extremities were in a state of al- 

 most complete paralysis with anaesthesia, while the mobility and sen- 

 sation of the lower limbs was quite normal. From the manner in 

 which this palsy had developed, it could be decidedly inferred that it 

 was the nervous trunks of the brachial plexus which were affected by 

 the vertebral disease, and not the spinal marrow. Rheumatic palsy, 

 which likewise not unfrequently affects a large number of nerves, does 

 not present any peculiarity with regard to its manner of extension, 

 and for a differential diagnosis we can only avail ourselves of the fact 

 that it is not apt to assume the form of hemiplegia or paraplegia. On 

 the other hand, the mode of development of lead-palsy is very charac- 

 teristic, so that from it alone the real nature of the disease may be de- 

 termined, and other forms of peripheral palsy, as well as the central 

 palsies, may be excluded from the diagnosis. Lead-poisoning always 

 affects the upper extremities first, attacking the extensors of the fin- 

 gers, hands, and arms in succession, while the flexors remain quite free 

 from disease. 



2. If, from the outset of an attack of palsy, there have never been 

 any derangements of the cerebral function, the origin of the disease 

 is, in all probability, peripheral. The converse of this proposition 

 also does not hold good ; for a paralysis may be combined with serious 

 cerebral disorder, and the paralysis may still be a peripheral one. 

 Ample proof of this condition is given in cases of tumors at the base 

 of the brain. 



3. When the affected nerve is a nerve of mixed function, the com- 

 oHcation of palsy with anaesthesia of the region known to be supplied 



