CASE 4. — A boy, mt. eleven, was admitted into the Richmond Hospital on the 2nd of September, 1810, under the care of Dr. Mac donnell. Upon the Sunday previous to his concussion of the brain, under the influence of which he remained insensible for three quarters of an hour. The accident occurred at some distance from town. Before an hour elapsed the boy was visited by a surgeon, who, it is said, forcibly extended the limb, and then applied a narrow roller tightly round the wrist. On the following day (Monday) the patient admission he had been thrown from a horse with great violence. The lower extremity of the left radius was broken, and he sustained a complained of intense pain in the limb ; the hand became cold and discoloured ; the roller was not removed nor relaxed. On Tuesday, (lark coloured vesicles formed ; constitutional symptoms of the gangrene showed themselves; the pulse 159, feeble; countenance anxious. The gangrene increased for two days more. and reached within two inches of the elbow joint. On the sixth day a line of separation showed itself; and on the twenty-fourth day the bones were sawn through, and the wound soon healed.
Dissection of amputated Forearm. — The radius was found to have been completely broken through in the line of junction with its lower epiphysis. The ulna was entire. The preparation of the disjoined epiphysis and gangrened hand is preserved in the Museum of the Richmond Hospital.
The causes which have been known to pro duce a disjunction of the epiphysis are said to be similar to those which produce a transverse fracture of the bone close to the wrist-joint: but why in one case we should have a fracture, and in another a disjunction of the epiphysis, we cannot say. All my own observation has, as yet, taught me relative to this subject from the eases I have seen and inquired into, has been that the cause producing the disjunction in question has always been a violent one.
When a patient has suffered a disjunction of the lower epiphysis of the radius, there is, in general, much deformity observable in the region of the wrist. The hand, carpus, and lower fragment are carried backwards, and form together a plane which is from half an inch to three quarters of an inch behind the plane of the back part of the rest of the fore arm ; the transverse line of elevation of the lower fragment above the level of the dorsum of the upper fragment of the radius is very abrupt and obvious : and the first impression on the mind is, that a dislocation backwards of the carpus and hand is the accident which has occurred. This abrupt transverse ridge and depression are crossed vertically by the extensor tendons of the carpus; and pressure with the fingers discovers these longitudinal tendinous bands to be on the stretch, having been forcibly elevated from the back part of the radius as they pass to their grooves formed in the lower fragment.
The palmar surface of the forearm is un usually convex from above downwards, and does not present a salient angle in front, such as we might expect from the abrupt depression we noticed on the dorsum of the wrist and forearm. This convexity of the forearm in front, however, abruptly terminates in a trans verse narrow sulcus which marks the situation of the upper margin of the anterior annular ligament. The radial margin of the forearm is concave, and the ulnar margin presents a cor responding convexity. The patient complains much of pain, and has the same inability to move the forearm and hand as in cases of fracture.
By the above-mentioned signs we become informed that a solution of continuity in or near to the transverse line of junction of the lower epiphysis of the radius exists : hut without having had any opportunity of insti tuting an anatomical examination, we believe it would be difficult for any one to affirm whether the case were one of fracture, or disjunction of the epiphysis. Some writers seem to think that the case of disjunction of the epiphysis may be recognised by the circumstance, that, although there is an evi dent solution of continuity in the line of the radius, the crepitus of an ordinary fracture cannot be produced. To which we reply, that the absence of crepitation is not by any means unusual in cases of fracture of the ra dius in the region of the wrist; and, therefore, from this observation no useful inference can be deduced to aid our diagnosis.
In the examples of disjunction we have seen, we have always noticed a fixed condi tion, as it were, from the interlocking with each other of the portions of the disjoinecl radius ; so that it seemed quite vain to seek for crepitus ; — indeed we found it invariably demanded a considerable force in these cases to restore the limb to its original form.
We believe it is impossible to make a dif ferential diagnosis entirely to be relied on in these cases ; but we may, we think, conjec ture that the disjunction in question exists rather than a fracture, when the age of the patient is under eighteen or nineteen years, and the situation of the solution of con tinuity is in the exact transverse line of the junction of the epiphysis to the shaft of the bone. If, however, the diagnosis be difficult, we have practically little to regret this cir cumstance, because the prognosis and thy treatment will be the same in both cases.