The right extremity presented an example of luxation of the carpus forwards, while in the left was afforded an instance of displace ment of the carpus backwards.
Right Extrenzity.— The upper arm and hand, as already mentioned, bore a just pro portion to each other, and to the stature of the individual, but the forearms were scarcely one half the usual length. The first range of the carpus was articulated with the anterior aspect of the radius, which bone was only four inches and a half in length (fig. 927.). The ulna, six inches in length, was prolonged below the radius nearly half an inch, its lower extremity was destitute of the rounded head, which in the normal state is received into the concavity of the radius, and was carried for wards outwards and upwards (see fig. 927.). About half an inch above the level of its lower extremity it was in contact with the radius by a very small surface which was destitute of cartilage. An anterior and pos terior ligament connected the two bones in this situation, and permitted a very slight degree of motion between them. The lower extremity of the radius was totally destitute of articulating surface, and was represented by a rounded and blunt•margin.
The surface for articulation with the carpus was placed altogether on the anterior aspect of the bone. It consisted of a deep excava tion of an oblong form, and its longest diame ter running somewhat transversely ; it was tolerably smooth, though not invested with cartilage.
The radius and ulna were not only remark ably short, but likewise atrophied, both as to breadth and thickness.
Their superior extremities, with the excep tion of being unusually small, presented no abnormal appearance.
The bones of the first row of the carpus were in a state of atrophy, especially the semi-lunar bone. When the hand was flexed
at a right angle with the forearm, the lower end of the ulna formed a most conspicuous projection, while during extension, two pro minences were seen ; one, in front, caused by the carpus, the other posteriorly, mark ing the position of the lower extremities of the bones of the forearm. The hand was inclined to the radial side of the forearm ; it admitted of being flexed to a right angle, and could be extended perfectly. The ex tensor tendons in their passage from the forearm to the hand were lodged in deep and narrow grooves, or channels, formed on the dorsal aspect of the radius.
Upon the left side the deformity was equally remarkable, although the reverse of that no ticed on the right side. The carpus was re ceived into a socket formed for it by the radius and ulna. This socket was not at the lowest extremity of the bones of the forearm but near to it, and on the dorsal aspect of the bones, and it presented somewhat a glenoid shape, the longest diameter of which was directed obliquely downwards and in wards. With respect to the carpus, there was neither a scaphoid nor semi-lunar bone. The hand placed in the state of extension formed a right angle with the forearm, but the patient had the power of bringing it to a straight line with the latter, in which position two prominences were seen ; but, contrary to what was observed on the opposite side, the dorsal projection was here formed by the carpus, the extremities of the radius and ulna con stituting the palmar eminences (see fig. 927.). In this left extremity, the carpus and forearm, including the elbow joint, were malformed, as well as the wrist-joint, but the rest of the skeleton, with the exception of the right wrist-joint and forearm, was quite normal.