But before definitely deciding it will be prudent to await the development of some of the characteristic alterations of structure appertaining to rheumatoid arthritis. An affection of the shoulder frequently occurs which resembles in many respects rheumatoid arthritis, and has been well described by Simon Duplay[253] and W. Pepper.[254] It usually follows an injury, such as contusion, sprain, etc., of the joint, but may be spontaneous; it is unattended by swelling or deformity. Its early symptoms are pain on pressure of the shoulder a little below the outer border of the acromion, and especially behind it and at the coracoid process, also about the insertion of the deltoid and below the acromion during movements of the joint, especially when the arm is raised from the side or rotated inwardly; early restriction of these movements, which increases till a fibrous ankylosis becomes established and scapula and humerus move together as one piece, motion between those bones no longer existing, and forcible attempts to produce it giving great pain, and sometimes producing {94} crepitus in or about the articulation; sometimes early numbness and pain down the member to the hand in the course of the ulnar, internal cutaneous, or the radial nerve; vicious and painful semiflexion of the elbow; after a time wasting of the group of muscles which move the shoulder-joint. Although usually monoarticular and of traumatic origin, I have seen it affect first one and then the other shoulder in the absence of any known injury, and beginning like a neuritis or a neuralgia of the scapulo-humeral nerves. Duplay, however, regards it as a periarthritis. It may be distinguished from the rheumatoid arthritis by the absence of effusion into or enlargement of the articulation, and of deformity of the bones; by the early restriction of the movements and the rapid development of adhesions which fix the articulation; and by the curability of the disease. [Footnote 253: _Archives Générales de Méd._, Nov., 1872, pp. 512-542.] [Footnote 254: _Archives of Med._, Oct., 1880.]