The conditions which demand surgical interference in paraplegia due to compression of the spinal cord are by no means clearly defined. There are two chief reasons for this: first, the difficulty in diagnosing accurately the cause of the paraplegia; and second, the difficulty of distinguishing between cause and effect when we attempt to determine the results attained by our surgical interference. When a cure results after operation it is often impossible to make sure that recovery would not have ensued had Nature been left unaided to pursue her course. Nevertheless, it is obvious that certain cases are definitely improved by surgical interference, and not infrequently it holds out the only hope of relief. In attempting to define the indications for operation I have made a study of fourteen cases which have come under my care.
Hemorrhage within the neural canal may be the cause of the compression. This may be