MEMOIR XIII.
ON THE FRACTURE OF THE ROTULA.
§ I.
1. The rotula, a sort of bony production of the sesamoid kind, attached to the tendon common to the extensors of the leg, represents a moveable pulley, intended to slide on that formed by the separation of the condyls of the os femoris. It protects the joint which it covers, and, in point of structure, use, and situation, greatly resembles the olecranon, from which it differs only in this, that, instead of being a continuation or process of the tibia as the olecranon is of the ulna, it is only attached to that bone by a strong and thick ligament which is inserted into its tuberosity. Hence it follows, that between the injuries of the one and the other, there must be a great analogy: and indeed most of the signs characteristic of fractures of the olecranon, are characteristic also of those of the rotula, and the treatment which, in such cases, is suitable for the former, differs but little from that required by the latter.
§ II.
OF THE VARIETIES AND CAUSES.
2. Fractures of the rotula may, in general, assume any direction, transverse, longitudinal, or oblique: but the first kind occurs in practice much more frequently than the others; and so great indeed is the disproportion, that it has almost exclusively attracted the attention of authors, in the numerous forms of apparatus invented to retain the fragments.
3. A shattering of the bone, the effect of a violent blow; a contusion; an echymosis; an effusion of blood into the adjacent soft parts; one or more wounds of the soft parts, with or without an opening into the joint; a swelling, the degree of which varies greatly, according to the state of the fracture, and the disposition of the subject, but which is constantly present; a double division of the bone, one of which, being longitudinal, forms an angle with the other, which is transverse; and a concomitant fracture of the condyls of the os femoris, or of the tibia: such are the varieties and complications, of which the fracture under consideration is susceptible.
4. But this fracture may be produced in two modes. 1st, by the action of external bodies: 2dly, by that of the extensor muscles. The first mode of division takes place in falls on the knee, or when a body in motion strikes against it, and, in this case, there is no counter-stroke, the rotula being too small for such an occurrence, and always sustaining the fracture where it receives the blow. In the second, the fall is only subsequent to the fracture, and, as Camper has well observed, is most frequently the effect of it. For instance, the line of gravity of the body is, by some cause, removed behind it; the anterior muscles contract themselves to bring it forward again; the extensors act on the rotula; it is broken, and a fall ensues. Again, the leg is suddenly thrown into a state of violent extension; the extensors act with great force; a fracture is the consequence, and the patient falls. A soldier once fractured his rotula in kicking at his serjeant; thus the olecranon, in like manner, has been broken by throwing a stone. A man, in the Hotel-Dieu, fractured the rotula of each knee, in the operating room, by means of convulsive motions, produced by the operation of lithotomy.
5. The action of external bodies, can alone produce a longitudinal fracture, as when a person falls on a sharp projecting piece of timber: but this may also produce a transverse fracture. On the other hand, muscular action can never give rise to any but the latter kind, since the direction of this fracture is at a right angle with that of the extensors. A fracture resulting from the action of external bodies, is oftentimes accompanied by a wound, a contusion, or a shattering of the part (2); a fracture, arising from muscular action, is always simple, except as to a swelling around the joint. The latter cause may, instead of fracturing the rotula, rupture the common tendon of the muscles, or, what is more common, the inferior ligament. Desault has seen many examples of this: Petit has also observed several, and Sabatier has sometimes met with them. External violence seldom produces this double accident.
§ III.
OF THE SIGNS AND THE DISPLACEMENT.
6. In longitudinal fractures the diagnosis is always accompanied with more or less difficulty, because the extensor muscles, drawing by their contractions the two fragments equally upwards, and the inferior ligament holding them equally down, tend to keep them in apposition, and to prevent them from separating. Sometimes also the ligamentous production which covers the rotula, remains entire and serves to keep the fragments together. It will be necessary, therefore, should the existence of such a fracture be suspected, to move the two sides of the rotula in opposite directions, by pressing them to the right and to the left, in order to arrive at certainty on the subject. Should a wound exist, as is oftentimes the case (5) the diagnosis is less difficult.
7. If the division be transverse, the diagnosis becomes then as plain and easy, as it is difficult and obscure in cases where it is longitudinal. In such a case, a considerable separation or space exists between the two fragments, sensible to the touch, when the hand is placed on the knee. In this separation, the fragments are not displaced by the same means. The superior fragment being attached to the extensors, is drawn upwards with great force by these muscles, the action of which the rotula no longer resists. The lower fragment, on the other hand, being attached only to the inferior ligament, is not moved by any muscle, and cannot be displaced in any other way than by the motions of the leg with which it is still connected.
8. Hence it follows, 1st, that, in a state of extension, the separation is the least possible, because it is then produced on the part of the superior fragment only; 2dly, that in a state of flexion it is greatest, because then both fragments concur alike in producing it; 3dly, that it may be increased or diminished by varying the degrees of flexion.
9. This fracture is further characterized by the following circumstances, namely, a practicability of moving the fragments transversely in opposite directions, and of producing, by that means, some degree of crepitation, provided they be first brought close together; by the pain which accompanies these motions; by the swelling common to every kind of fracture of the rotula, and which, if very great, may involve the other signs in more or less uncertainty; by a difficulty of standing; and an almost entire loss of the power of walking, in consequence of the extensors being no longer able to communicate motion to the leg, unless when the fracture exists very low down, near to the inferior ligament.
10. The touch will always discover in what part of the bone the fracture is situated, which, if it be oblique, will partake more or less of the characters of the longitudinal or the transverse, accordingly as it approaches to the one or the other.
§ IV.
OF THE PROGNOSIS.
11. Many authors have pretended that fractures of the rotula cannot be cured, and it even appears that the Academy of Surgery adopted this opinion, on receiving a memoir from a Flemish physician, which contained several facts tending to establish that principle. But what do these facts prove? That in some particular cases, reunion did not take place, but they do not show that this was owing to the nature of the fracture.
12. But, what, in such cases, could prevent a cure from taking place? The structure of the rotula differs, say they, from that of the other bones. Now, admitting this difference of structure to be real, it certainly approaches to the structure of tendons to which indeed it bears a strong affinity. But, who does not know, that, when tendons are divided, they unite as readily as bones? Besides, is not the power of reunion common to every part endowed with life? I have already shown, when treating of other fractures that communicate with joints, what credit is due to those hypotheses so often revived but never confirmed, nay even clearly proved to be unfounded, such as, an effusion of callus into the joint, a failure of reunion from a want of periosteum on the posterior part of the bone, the synovia diluting the matter of callus, and thus preventing it from being duly prepared, &c.
13. The inflammation of the articulating surfaces and of the ligaments around the joint, ought to have more influence in constituting an unfavourable prognosis, than any circumstance that authors have mentioned. But experience proves, that, when judiciously treated, these fractures are not accompanied by that accident, and even that the swelling, which for the most part attends them, always yields more or less speedily, when a bandage, uniformly applied, presses equally on all parts around the joint, and thus forms a kind of discutient, while at the same time it retains the fragments.
14. Pare, Fabricius of Hilden, and a number of other writers, have pretended, that some degree of lameness must always be the consequence of this fracture. But, from what causes must this lameness so certainly arise? Is it from a want of reunion in the part? I have already shown (11 and 12) that this apprehension is wholly unfounded. Is it from an anchylosis? This accident cannot take place, except either in consequence of inflammation occurring in the articulating surfaces, (and I have already shown how that may be avoided, 13) or of a stiffness in the ligaments, and I shall hereafter make it appear that that may be readily prevented by motion. Is it from the fragments being drawn asunder, and in that state united by an intermediate substance of too great an extent? I shall prove, that a bandage properly constructed, is always sufficient to keep these fragments in contact.
From these considerations it appears, that writers have, in general, without sufficient cause, given an unfavourable prognosis, in relation to fractures of the rotula, which have, indeed, a great affinity to other affections of the same kind.
§ V.
OF THE REDUCTION AND THE MEANS OF MAINTAINING IT.
15. I have already observed (7), that the causes of the separation of the fragments are, as far as respects the upper one, the contraction of the extensor muscles; and, in relation to the lower one, the flexion of the leg; whence it follows, that the means of preserving contact between these fragments are 1st, all those that are calculated for the prevention of muscular action; 2dly, such as may keep the limb in a state of permanent extension. Hence two leading curative indications must be fulfilled by the bandage constructed for fractures of the rotula: the last of these indications presents in general but little difficulty; but, with regard to the other, the case is different. To fulfil the latter, it is necessary first, to weaken the contractile force of the muscles, and by that means diminish the effort which they make to draw the superior fragment upwards; and then, to oppose to them a proper mechanical resistance, which, by acting in a direction the very reverse of that in which they act, may countervail their efforts.
16. But the force of contraction is diminished, 1st, by throwing the muscular fibres into a state of relaxation; this end is best attained by bending the thigh on the pelvis: 2dly, by making compression over the whole limb, by means of a circular bandage, which, by confining the muscles, tends to restrain and weaken their action. Thus it is known that the advantage of the bandage employed to unite transverse wounds, consists chiefly in that compression which, by diminishing muscular action, prevents the retraction of their edges. Another advantage resulting from the bandage in this case is, that it prevents the swelling of the limb.
17. As to the mechanical resistance, which must act in a direction opposite to that of the contraction of the muscles, and, by that means, prevent the displacement of the superior fragment, it cannot, in the present case, be of the same nature as in fractures of the thigh, the clavicle, &c. where permanent extension is practised. The superior fragment offers too small a purchase for any extending forces to act on. This resistance must be made, then, by placing some body above this fragment, and retaining it in that situation with a force sufficient to hinder the fragment from rising upwards: such as a few turns of a roller drawn tight, a bit of leather, some hollow compresses, &c.
18. It is evident from the foregoing principles, that every bandage intended to retain a transverse fracture of the rotula, ought to be calculated to maintain the following state of things: 1st, the extension of the leg on the thigh; 2dly, the flexion of the thigh on the pelvis; 3dly, a uniform compression over the whole limb; and, 4thly, some mechanical resistance properly secured above the superior fragment: the three last expedients relate to the displacement of that fragment alone; while the first has a relation to that of the lower one. Let us examine whether or not the bandages, hitherto employed by different authors, be calculated for these purposes.
19. M. Valentin, believing that position alone was sufficient to retain the fragments in contact, neglected the application of apparatus entirely, which he even considered as hurtful, in consequence of the swelling it produced; but experience soon proved the insufficiency of this method. The slightest movement, or the least effort on the part of the patient, made the extensor muscles contract, which, drawing the superior fragment upwards, separated it from the lower one; and, as the time of reunion is in direct proportion to the distance of the fragments from each other, it must, under such treatment, have been necessarily tedious, and sometimes must have even failed altogether.
20. As to a swelling being produced by the bandage, this never occurs, unless when some openings are left, through which the integuments protruding become tumefied: but, when the pressure is uniform throughout, when the fluids find throughout an equal resistance, this accident is not to be apprehended, as is proved by the practice of Desault, who never met with it; on the contrary, a bandage properly constructed and applied, is calculated to prevent swelling (16).
Mere position, then, though always of service in this affection, is not alone sufficient, because it fulfils only the first of the indications or principles laid down with respect to every form of apparatus for transverse fractures (18), namely, that which relates only to the lower fragment; while those that relate to the upper one, remain still to be fulfilled.
21. Most authors have employed, with a view to these, a kind of figure of 8 bandage, known in art by the name of Kiastre,[32] and approved of by Petit, Heister, &c. This is made of a roller formed into two balls, which are brought across each other alternately under the ham, passing over two hollow or forked compresses, that enclose the two fragments of the rotula.
But the unequal pressure which this makes on the unequally projecting parts of the knee, renders its application extremely painful, particularly below, where the pasteboard covering applied by Louis, immediately on the skin, afforded but a feeble protection to the tendons of the flexors. Besides, it did not prevent the swelling, which is indeed a necessary consequence both of this unequal pressure, and of the openings left between the casts of the bandage. This swelling is taken notice of by all writers, and is, according to them, one of the troublesome circumstances attending the fracture. The third indication is not all fulfilled (18).
22. The extensor muscles, not being at all compressed, will act with their whole force on the upper fragment, and, on the slightest effort of the patient, overcome the resistance of the bandage, the action of which, being oblique with respect to the fragment, is inconsiderable, unless it be drawn very tight, and thus a displacement will again occur. This obliquity of the turns of the roller obliges the surgeon, either to draw it very tight, in which case a swelling is inevitable, or to make it but moderately tight, and then the apparatus will be insufficient to resist the action of the muscles.
23. Most of the objections to the ancient apparatus for fractures of the rotula, apply also both to that proposed by Ravaton in his surgery, and to that which Bell employs in his practice. Both of these, while they fail in making sufficient resistance to muscular action, as well as in fulfilling the third condition laid down as necessary to every bandage (18), contribute to the swelling, and can rarely produce a perfect contact between the fragments. Thus Bell has well observed, that the reunion is rarely perfect, and that there is always a separation more or less perceptible.
24. The complication, the intricacy, the expense, and other more weighty inconveniences of the machine described by Garengeot in his treatise on instruments, and employed, for the first time, by Arnaud, and also of that which was proposed and used by Solingen, have, long since, entirely banished them from among the means of reduction.
25. Some practitioners have advised the uniting bandage used in cases of transverse wounds, which is formed, as is well known, of two small rollers or strips placed in the longitudinal direction of the limb, one of them having holes in it, to which the divisions of the other are fastened. Both of these are first secured by circular turns; being then drawn in opposite directions so as to meet, they draw the parts on which they are applied in the same directions. But the action of this bandage is confined to the integuments, and would have of course but a feeble influence on the fragments beneath. It is also attended with this further inconvenience, that by wrinkling the integuments, and throwing them into folds, it might press them down between the fragments, and thus prevent their contact. Besides, it is liable to most of the objections urged against the preceding one.
26. This view of the means employed by different practitioners, to counteract the causes of displacement in this fracture, are sufficient to convince us, that the difficulties hitherto experienced in the treatment of it, have arisen from the feebleness of the former, and the strength of the latter. So great indeed have been these difficulties, that some authors, conceiving a reunion impossible, have, in conformity to such an opinion, though contrary to all the rules and principles of the profession, advised us to abandon the patient to himself. But I have already exposed the fallacy of that opinion, respecting the want of a healing power in the rotula (12), an opinion which, if generally adopted, would give rise to consequences of the most serious nature. In the present case, as in all other fractures, the contact of the fragments ought to be the chief object of the surgeon’s efforts.
27. But ought this contact to be perfect and exact? Several authors, particularly Bell, have conceived, that the motions of the limb can be performed as well with a slight separation of the fragments. Pott even declares that such a separation will enable the patient, after his recovery, to walk with more ease. Flajani advances the same opinion in a dissertation on the subject.
From this doctrine arose a new mode of treatment, which consisted in not suffering the fragments to be at rest. They were accordingly, during the cure, put frequently in motion, the more effectually to prevent an anchylosis, which is sometimes the consequence of this fracture.
28. But, on the one hand, it is difficult to conceive, on what this opinion of these authors can be founded; while, on the other, reason declares, in the plainest and most forcible terms, that the more the state of a bone, after it has been broken, differs from its natural state, the less free will be the exercise of its functions, and, that the perfection of the treatment of fractures consists, in leaving behind it no vestige of the accident.
29. This truth was frequently confirmed in the experience of Desault, who had an opportunity of seeing numerous fractures of the rotula, both in the Hotel-Dieu, and in his private practice. He always observed, that, when the separation of the fragments was considerable, and the ligamento-cartilaginous substance uniting them was of some extent, standing and walking were performed with much difficulty; that the patient was exposed to frequent falls, from the want of a proper correspondence, in point of strength and motion, between the two limbs; and that, on the contrary, the less extensive the separation and the substance that filled it up were, the more free and easy were the motions of the part, which still remained, however, somewhat defective and imperfect, unless every vestige of the division was obliterated.
Paul of Egina long since observed, that, when no means of reduction were employed, though the patient might walk tolerably well on a level surface, he could not, without difficulty go up an ascent.
30. From what has been said, it follows, 1st, that in the treatment of this fracture, the perfect contact of the fragments ought to be the principal object of the practitioner; 2dly, that the kinds of apparatus employed by different authors, are but ill calculated for the attainment of this end, because they fulfil but imperfectly the indications formerly laid down (18). Let us see whether or not the apparatus of Desault be any better suited to this purpose.
31. The bandage, which he employed in this case, analogous to that for fractures of the olecranon, is composed, 1st, of one splint, two inches broad, and long enough to reach from the tuberosity of the ischium, to a little above the heel; 2dly, of two rollers, five or six yards long, and nearly three inches wide; 3dly, of another single roller, with two holes about the middle of it, a little longer than the injured limb of the patient, along the fore part of which it must be extended.
32. Every thing being arranged for the application of the apparatus,
1st, One assistant secures the pelvis, in the same manner as in fractures of the lower extremities; while another keeps the leg in a state of perfect extension on the thigh, and the thigh on the pelvis.
2dly, The surgeon, then, standing by the side of the fractured limb, extends along the anterior part of the leg and thigh the roller with holes in it, having previously wet it with vegeto-mineral water, taking care to make the two openings correspond to the lateral parts of the rotula, that, by being thus better adapted to its shape, it may not be thrown into wrinkles.
3dly, He then secures it on the top of the foot, by three circular casts of a roller placed one over the other, three or four inches above its lower end which must next be turned up over the three first casts, and made fast by two other ones. Then, while the compress roller[33] is secured above by an assistant, he passes up along the leg by oblique and reverse turns, according to the inequalities of the limb.
4thly, Having arrived at the lower part of the knee, he pushes the lower fragment upwards, and makes below it two or three circular turns to secure it. He then gives the roller into the hands of an assistant, and directing him who holds the long compress roller, to draw it forcibly upwards, pushes the integuments of the knee in the same direction, lest, by becoming interposed between the fragments, they might prove an obstacle to their reunion. Passing then the fingers of his left hand through the holes in the compress-roller he places them behind the superior fragment and pushes it forcibly downwards.
5thly, When the reunion of the fragments is exact, without any space intervening, he resumes the roller, and passing it obliquely under the ham, and bringing it up again behind the superior fragment, withdraws his fingers which held this fragment down. In place of his fingers, he then applies two or three tight circular casts, covers the knee with several oblique casts in form of the figure of 8, so as to leave no opening between them, and, then, continues the bandage up along the thigh, securing by it the compress-roller extended along the fore part of the limb.
6thly, When he has arrived at the upper part of the limb, the assistant who holds the compress-roller, drawing it forcibly upwards, doubles down its end over the circular casts. The surgeon next fixing this end by several additional casts, descends again along the thigh, covers the knee by a few more oblique turns, and finishes with the roller on the leg.
33. This first part of the bandage evidently fulfils the third and fourth indications (18). The compression of the roller on the muscles weakening their action and impeding their motions prevents their tendency to draw the superior fragment upwards: while the circular casts passed behind this fragment, acting in opposition to the muscular contractions, prevents it from moving upwards in obedience to them. The long compress-roller, stretched on the fore part of the limb, being first secured below, and then drawn forcibly upwards, presses the casts of the roller against each other, and prevents those that correspond to the thigh from slipping upwards, and thus abandoning the superior fragment, and prevents also those on the leg from slipping down and withdrawing their support from the inferior fragment. As there remains no vacant space between the circular turns, their pressure is uniform throughout: no swelling can consequently supervene (20).
34. But the first and second indications remain still to be fulfilled (18): it is necessary to prevent the separation of the lower fragment, by the extension of the leg on the thigh, and to throw the muscles into a state of relaxation by extending the thigh on the pelvis, and to maintain permanently, by the apparatus, that double position, which the assistant maintains only during the operation.
35. To obtain the first effect different means have been employed; but none answers so well, to extend the limb and retain it immoveably in that state, as a long and strong splint, placed, as Desault did it, subsequently to the application of the first part of the bandage, along the posterior part of the limb. An assistant must hold the end of this splint, while the surgeon secures it in its place by the second roller (31): in this way the extension of the leg is effected.
36. To obtain the extension of the thigh, it is necessary to place on the top of each other, two or three bolsters or little bags filled with chaff, so disposed as to form an inclined plain, considerably elevated towards the heel above the level of the bed, but which, gradually descending to the same level towards the tuberosity of the ischium, forms a supporting basis on which the whole limb may rest in a uniform manner. By this twofold extension of the leg and of the thigh, the lower fragment is kept up immoveably, and the muscles are kept in a state of relaxation.
Hence it follows, that this bandage fulfils extremely well the conditions laid down (18), and that it ought to be preferred to all the others (19...25), which answered the indications only in part.
37. Whatever may be the advantages of this bandage over the others, it must still be acknowledged to have its inconveniences. The rollers become relaxed in a short time; their compression is less active; the muscles, being less confined, contract more readily; hence the necessity of frequently repeating the application of the apparatus, a circumstance which is very troublesome, on account of the roller which composes it, and covers the whole limb. The resistance of it even when it is recently applied, is not always equal to the power of the muscles, whence the most assiduous attention is necessary, to obtain such a consolidation as to leave no trace of the fracture behind. Few persons ever possessed, like Desault, the art of overlooking nothing that might in any way contribute to the success of his treatment: from this, no less than from the excellence of his processes, arose the number of his cures. Let us confirm, by a few examples selected from among a great many, the doctrine here laid down. The following cases were collected by Julian and Bezard.
Case I. Francis Leclert, of a sanguine temperament, fell on the 7th of October, 1790, on his right knee, and produced a transverse fracture of the rotula. He was not able to rise; he was carried home, where a surgeon, on discovering the nature of his disease, advised him to be taken to the Hotel-Dieu.
He was conveyed thither on the day following, and, in the interval, a considerable swelling had occurred around the joint. The usual bandage was employed; the pains ceased immediately after its application; a copious blood-letting was directed, and a low diet was prescribed.
The whole apparatus was wet with vegeto-mineral water, two or three times a day. On the next day some light food was allowed, and the quantity increased by degrees, till in a short time the patient returned to his usual regimen. Eighth day, the swelling being almost gone, the bandage had become relaxed it was therefore reapplied. Every day the inclined plain formed by the bolsters was carefully examined, and put in order again as often as it became deranged.
Fifteenth day, a new application of the apparatus: twentieth day, an evacuation in consequence of a bilious disposition. Nothing particular occurred from this time till the completion of the cure, which took place on the sixty-seventh day after the accident: no depression existed at the place of the fracture: the motions were perfectly free; these were aided, by daily exercising the knee joint for some time.
Case II. Vincent Grenier, aged thirty-eight, making a false step, fell on the rotula, and fractured it, on the 6th of June, 1791: he was brought to the Hotel-Dieu, where Desault demonstrated to his pupils, by the usual signs the existence of the disease: a considerable swelling had already taken place. The bandage formerly described was applied: the same precaution as in the preceding case; apparatus examined every day; renewed as often as relaxed; extension maintained with great exactness. On the forty-fifth day, the consolidation was nearly effected; on the fifty-second it was complete, the joint was exercised for some time, and on the seventy-seventh day the cure being in all respects complete, the patient was discharged.