The nonchalance with which not a few writers dismiss the diagnosis of acute gout when located in the great toe or elsewhere in the foot is, to say the least of it, somewhat remarkable. “It is a very easy matter,” say they, and as an earnest of their good faith are silent as to the many pitfalls that await the unwary. Should they deign to differential diagnosis, they are at pains to discriminate between it and acute articular rheumatism, which re classical outbreaks in the toe seems a little superfluous! But not a word of traumatic lesions, infective processes and static deformities, all infinitely more likely stumbling-blocks.
Did all cases conform to the classic type, acute sthenic gout, it might be held relatively easy. But such are not, to say the least of it, common nowadays. More often than not our examples are, as Garrod terms them, of acute asthenic character. As he observes: “There may be indeed pain and tenderness in the toe, and some amount of swelling, but accompanied with little heat or redness, and all febrile disturbance may be absent; still œdema is generally observed and itching and desquamation follow.”
That diseases, like their victims, alter with environment is but too clear. Who can doubt that the gout of the Regency has to-day assumed a milder clinical facies? Physicians of those days were haunted with the fear of confounding it with erysipelas and phlegmon. Still, while no such fears apparently beset us to-day, it were well to walk circumspectly.
Thus, recently a friend of mine came across an instance of what he deemed acute gout in a metacarpo-phalangeal joint. Its failure to respond to colchicum and the growing intensity and extent of the local inflammation suggested incision, when, lo, pus issued, to the subject’s comfort, but to his own chastening!
There are, however, many more likely sources of fallacy, these, too, of the most diverse type, inasmuch as they differ according to the exact location in the foot of the assumed gouty process. For while the big toe is the site of predilection for the initial manifestation, it is not always so. The primary outbreak may be located in any of the smaller joints of the foot, or outside them in related structures: in the heel, the sole, or the tendo Achillis. These vagaries greatly enhance the difficulties of diagnosis. For the process of differentiation will vary according to the particular joint or structure involved, the predilections of certain infective processes, not to mention the marked liability of the foot to painful disturbances of static origin.
Inasmuch as the primary outbreak may be located in any part of the foot, we purpose, for reasons just cited, dealing seriatim with gout in (1) the big toe; (2) the instep; (3) the heel; (4) the sole.
Infections.—There is no â priori reason why any of the infections may not find a nidus in the first metatarso-phalangeal joint. Thus, Garrod, as we know, held gouty subjects specially liable to pyæmia. In rare instances, the primary focus has been in or near the great toe, and has consequently been mistaken for gout. The rapid progress of the disease would of course soon clear up the nature of the case. But if the subject has previously suffered from gout, such a diagnostic error at first sight is quite excusable. Accordingly, as a safeguard in all doubtful cases, inquiry should be made as to the existence of bladder troubles, piles, etc., especially any recent operation in this or other regions.
Again, while gout in its articular form is rarely, if ever, met with in children, it must be recalled, on the authority of Sir James Goodhart, that rheumatism in their instance is occasionally limited to one joint. Moreover, this distinguished physician actually saw it localised in the great toe, “in a case in which the subsequent course of the disease showed that it was acute rheumatism.”
Acute Gonococcal Arthritis.—We may recall that Van Swieten, a disciple of Boerhaave, held that sometimes a wife while nursing her gouty husband had contracted the same disorder. A tribute, we fear, to Van Swieten’s diplomacy rather than to his clinical acumen—an euphemism for gonorrhœal rheumatism!
Of course in adolescents or in young adults monarticular pain, with or without swelling, heat, or redness, should not suggest “gout,” but an infective disorder either in the joint or the related bone-ends. At the same time middle-aged men enjoy no immunity from gonorrhœa, and we may add that gonococcal infection of the metatarso-phalangeal joints is not so uncommon. When located in that of the great toe, it is easy to see how readily the acute arthritis may be confused with gout. But, unlike the latter, its duration is measured by months or weeks rather than by days. It is well to recollect, too, that “gouty” persons are more prone to develop arthritis following gonococcal infection. Given therefore a history even remote, we should in doubtful cases recall the longevity of the organism, its persistence in the prostatic recesses, and the need for bacteriological investigation.
Traumatic Lesions.—Its exposed situation renders the big toe very liable to trauma. Often, too, the injury being slight, and not followed by any immediate consequences, the connection may easily be overlooked. A blow or a fall may readily bruise the synovial membrane without at first any external sign. But given trivial hæmorrhage into the cavity or subjacent tissues, an acute synovitis with effusion is induced.
Again, joint disorder following injury is usually monarticular, whereas the same when the outcome of so-called “constitutional” causes is generally oligo- or poly-articular. The relevancy of this is obvious when we recall that initial attacks of gout are monarticular. Accordingly, given a history of definite injury to the toe joint, the question arises, Is it acute gout or acute traumatic arthritis? this especially if the subject has not had a previous attack of gout at this site.
Here I would lay stress on the fact that indirect rather than direct traumatisms are more common antecedents or determinants of gout, viz., sprains or strains. Moreover, in reviewing the writings of the older physicians one is driven to the conclusion that frequently a septic cellulitis, synovitis, or a frankly traumatic arthritis was confused with acute gout.
The following examples cited by Scudamore are, we contend, susceptible of such an explanation: “A gentleman much subject to gout, when considering himself unusually well, underwent the slight operation of having the nail of the great toe cut on account of its improper growth. The toe was much pressed, and gouty inflammation was the immediate consequence.” In another case “the patient, never before having suffered the gout, tore off a broken portion of the thumb-nail, so as to make the part tender. Very soon the thumb and part of the hand put on a swollen and shiny appearance, and was exquisitely painful. A poultice was applied. Suddenly on the third evening the pain quitted the thumb and seized the toe, next the ankle, then the knee, and lastly the great toe of the other foot. Throughout he secured ease and sleep till the first light of the morning appeared, and hence facetiously observed that the gout in this respect assumed all the behaviour of a ghost.” Was not this probably a case of septic absorption with cellulitis and a mild degree of sapræmia, evoking arthralgic pains?
In conclusion, without denying the potentialities of trauma, whether direct or indirect, in determining an outbreak of gout, we would submit that its diagnosis under such circumstances should not be hastily arrived at, but by the slower process of elimination, this especially if the trauma has involved slight abrasions with the possibility of sepsis. A quick response to colchicum would of course be highly suggestive of gout.
Acute Osteoarthritis.—It is perhaps not so widely recognised as it should be that osteoarthritis not uncommonly attacks the metatarso-phalangeal joint of the great toe. It becomes enlarged owing to the hypertrophy of the articular ends. Like similar lesions in the small joints of the hand, the big toe joint from time to time undergoes exacerbation, with increased vascularity and local heat, which, though of minor degree, may by a superficial examiner be readily misinterpreted as gout. The parts are painful, somewhat swollen, hot, and tender, but the local symptoms are never intense, and constitutional disturbance is lacking. The presence of osteoarthritic lesions elsewhere and the revelations of skiagraphy will suffice for differentiation of such cases from asthenic articular gout.
Hallux Valgus with Inflamed Bunion.—Scudamore in his “Treatise on Gout” observes that “the bursal disease over the first joint of the great toe, which is familiarly known as bunion, is a very common complaint with gouty persons.” In view of the fact that no reference is made in the context to the absence or presence in such cases of a condition of hallux valgus, one is led to believe that Scudamore overlooked the deformity and regarded the local bursitis as the outcome of a gouty inflammation of this structure.
Bradford and Lovatt, discussing hallux valgus, observe: “There may be pain and irritability in the great toe joint, and in severe cases extreme pain and difficulty in walking, which is usually attributed by the patient to gout.” We would only qualify this statement by the fact that the local heat, redness, and swelling that in this condition so often follow slight injuries or excessive walking is not only so interpreted by the patient, but far too frequently also by his medical attendant.
Routine examination of the bare foot will minimise the chance of such a fallacy, though of course it must be borne in mind that a gouty subject may present this deformity. But when we recollect that hallux valgus of slight degree “is almost universally present after middle childhood,” we see that, given the presence of this static foot deformity, any inflammatory process in the superjacent structures is infinitely more likely to be due to an inflammatory bursitis than to a gouty arthritis.
Given an inflamed bursa with cellulitis spreading over the dorsum of the foot, confusion with acute sthenic gout is all too easy. But in our experience, mirabile dictu, the ordinary more or less chronic circumscribed redness over the bunion is but too commonly misinterpreted as gout, this particularly in women, despite the rarity with which gout attacks their toe and the frequency with which their footgear is precisely adapted to produce hallux valgus. Given therefore the presence of this static foot deformity, we should in the absence of objective stigmata of gout, viz., tophi, suspend our diagnosis pending observation of the results obtained by local treatment of the displaced toe.
Hallux Rigidus.—This deformity is but too often overlooked, and if marked by pain and more or less rigidity of the first metatarso-phalangeal joint, it may, in lack of adequate examination, be flippantly dismissed as “gout,” this more particularly in its later stages, when, in addition to pain and stiffness therein, the joint is swollen, tender to the touch, and the bony ends actually enlarged. Here again local examination, if carefully carried out, will suffice to obviate such errors, while the quick response to rest and appropriate applications, with correction of the frequently associated sunken arch, will sufficiently attest its true nature.
Metatarsalgia.—As pointed out in our previous work on Fibrositis, “this painful condition is more often than not confused with rheumatism or gout.” We have known subjects wander to nearly every spa on the Continent under such a misconception. Not to mention the financial expense, the dietetic penances imposed, the consequences of such faulty diagnosis, are by no means trivial, for the intensity of the suffering may reduce the walking capacity to a minimum.
The neuralgic pain radiates into the toes and often upwards into the leg, usually comes on while walking, and is relieved by the removal of the boot. For its detection any altered relationship in the position of the third, fourth, and fifth metatarsals, especially their displacement to a lower level than normal, should be noted, and any limitation of the power of dorsal flexion of the foot likewise estimated. The presence of callosities under the heads of the metatarsals is very suggestive of this painful condition.
Next to the metatarso-phalangeal joints, the tarsal articulations are the most frequent site of initial attacks of gout. Here again we would insist on the necessity of excluding infections of the tarsal joints or shafts and even more important, static foot deformities.
Gonococcal Arthritis.—In a table compiled by Garrod from those of Foucart, Brandes, Rollet, and Fournier, the relative frequency of the implication of individual joints in gonorrhœal arthritis shows that out of a total of 119 the tarsus and metatarsus were attacked in five instances. In the more acute cases the periarticular swelling, local heat, and pink blush may be confused with acute gout. The resemblance is enhanced in that, as in gout, the overlying tendon sheaths are liable to become inflamed and distended with fluid.
Tuberculous and Syphilitic Disease of the Tarsal Joints or the Related Joints.—In cases of obscure pain and inflammatory trouble in the instep the possibility of arthritic and bony lesions of this nature should not be overlooked, especially if there be suggestive lesions elsewhere, or if the history afford evidence of the possibility of such contingencies.
Pes Planus.—In all cases of pain and swelling, with or without redness, in the instep, it is well to recollect that, though flatfoot may for a long time exist without giving rise to symptoms, it frequently happens that, in sequence to some unusual strain on the plantar arch, the static disturbance in the foot enters quite abruptly on a painful phase. Congestion and swelling of the foot is common, and actual teno-synovitis of the tibial and peroneal muscles is not infrequent. Tenderness, too, at points of ligamentary strain is almost always present, and more or less constant pain.[40]
The frequency with which the local and referred pains of flatfoot are misinterpreted as “gout” and dietetic restrictions and other useless and uncalled-for methods of therapy enjoined is well exemplified by a case which has just left our consulting room.
The subject, a middle-aged spinster of lean kind, came to Bath for treatment of her supposed gout, and for which indeed she had previously received spa therapy. Her feet when bared showed a condition of double hallux valgus with related bursal thickenings. The occasional inflammation of these latter structures and the recital of doubtful ancestral proclivities were the sole evidence on which was based the diagnosis of gout. In addition, as is so frequent in hallux valgus, there was associated therewith a bilateral flatfoot, and it may be added that in the left foot a hammer-toe had been removed some years since. Unfortunately the neglected symmetrical flatfoot had, as so frequently happens, initiated, through the erroneous deflection of a body weight, a condition of chronic villous synovitis in both knees. This again was misinterpreted as but another proof of her assumed “gouty” diathesis. Reflecting upon human nature, how curious the reluctance with which such subjects elect to part with their “gout.” Women especially hold tenaciously thereto, even those of austere type, clinging to the taint handed down to them from some far-off ancestor whose “superfluity of naughtiness” was a by-word among his generation. To exchange gout, morbus dominorum, for “flatfoot” and inflamed “bunions,” savours of degradation, and to couple it with aspersions on their footgear is well-nigh insupportable. Nor are the “lords of creation,” we fear, exempt from this failing. We recall during the War being consulted by a highly placed officer who complained of gout. A well-preserved man of nigh sixty years of age, he obviously prided himself on being immaculately booted. As such patients frequently do, he brought his own diagnosis of “gout.” Removing his footgear, manifestly too small, his crucified toes stood out with bunions in a state of hot resentment. But impeachment of his boots was too much for him. Persuasion and argument were futile, and I doubt not he walks to-day stiff, a martyr to his vanity. “Il faut souffrir pour être belle.”
In some instances the first manifestations of gout occur in the heel, while in others the sheath of the neighbouring tendo Achillis is the part first invaded. Probably there is no region of the foot in which there exist more pitfalls, and doubly careful should we be before concluding that any painful or inflammatory condition thereof is one of “gout.”
Referred Pain.—Pain in the heel affords many loopholes for misinterpretation. It may, as Sir James Paget pointed out many years ago, be symptomatic of a renal calculus. In my own experience it is sometimes complained of by the subjects of internal hæmorrhoids, the pain waxing and waning with the variations in the rectal trouble, and only disappearing permanently when the piles have been radically treated. It is, again, a symptom sometimes complained of by the victims of enlarged prostate.
If the pain and tenderness be located on the under-surface of the os calcis, there are several misconceptions possible.
(1) Careful examination may reveal a tendency to flatfoot, the pain being referable to strain on the posterior insertion of the plantar fascia.
(2) The root of the trouble may be a gonococcal inflammation of the plantar fascia, or of the periosteum covering the os calcis.
(3) A skiagram may show the existence of a bony spur on the inferior surface of the os calcis.
(4) The bursa under the os calcis may be inflamed.
(5) Also, as Tubby has pointed out, pain in the heel may be referable to shortening of one leg or constant standing, and more rarely to tuberculous disease of the os calcis.
If the pain and tenderness be located on the posterior surface of the os calcis, or in the tendo Achillis, the following should be excluded before assigning the trouble to “gout”:—
(1) Post-calcaneal Bursitis.—Inflammation of the bursa lying between the os calcis and the tendo Achillis is not uncommon. It may be uni- or bi-lateral, and in the majority of instances is attributable to violent exercise, or chafing of the heel by ill-fitting boots. The local swelling and tenderness at the site of the inflamed bursa and its aggravation by plantar flexion of the foot will afford a clue to its true nature. (An exostosis projecting from the hinder surface is sometimes a cause of post-calcaneal bursitis.)
(2) Synovitis of the Tendo Achillis.—Symptoms very similar to those above described have been met with in a teno-synovitis of the tendo Achillis, as evidenced by swelling of the sheath, tenderness, and silky crepitus.
There is a wide disposition to regard all painful or unpleasant sensations in the sole of the foot as evidences of “goutiness.” It may be recalled that Strabo, according to Plutarch, apostrophised heat or itching of the feet at night as “the lisping of the gout.” Duckworth, too, emphasised the frequency of this symptom in the gouty, and Sir Charles Scudamore also held heat and dryness of the sole as frequent harbingers of acute attacks. Now, did we but confine our hazards as to gout only to cases marked by heat or itching in the sole, possibly little harm might result; but unfortunately there is a flippant readiness to relegate all obscure pains or abnormal sensations in the sole to the “gouty” category. Needless to say, this is quite unjustifiable. We need not reiterate the bounden necessity of excluding all static foot deformities, but we should in addition recall the various types of plantar neuralgia.
Plantar Neuralgia.—Occasionally, as we have pointed out elsewhere, the pain is of almost unendurable severity. It constitutes one of the types of so-called partial sciatica, the pain and paræsthesia being confined to the plantar nerves. Indeed, pain, numbness, hyperæsthesia, or sweating of the sole are often symptomatic of a definite neuritis. Such may follow typhoid fever or caisson disease, and in this latter be of aggravated type. When we realise that the pain in these cases may be limited to the tips of the toes or the ball of the great toe, we see how readily it may be confused with “gout.” Fortunately plantar neuralgia is exceptionally rare; but even after exclusion of the foregoing causes we should, before pronouncing any such neuralgia to be “gouty,” recollect that plantar neuralgia or hyperæsthesia is very common in alcoholism and hysteria.
Erythromelalgia.—Among the exceptional cases that find their way to spas are examples of this rare disorder. Almost invariably they come under the diagnosis of “gout” or “rheumatism.” When we reflect that in the majority of instances the initial burning pain typical of the disease is located in some part of the sole of one foot, and that the associated redness and vascularity may be delimited to the ball of the great toe, the heel, or outer or inner side of the foot, we see the danger of its being too easily referred to “gout.”
If seen at the zenith of an attack, the severe pain, the local heat, the intense purplish redness, the distension of the veins, and in some instances œdema, how close the resemblance to gout! Precisely also, as in gout, the simulation of a deep-seated inflammatory process is very pronounced. Indeed, in not a few examples of erythromelalgia fruitless incisions have been made. Accordingly in all cases of pain, redness, and swelling in the sole of the foot, we should canvass the possibility that we may be face to face with an instance of erythromelalgia, a disorder which, like gout, is most frequently met with in men of middle age.
In drawing to a close our remarks on the diagnosis of acute gout in the foot, we would emphasise the fact that in all such cases the bare feet should be thoroughly examined. For, apart from infective and traumatic lesions, the frequency with which the various static foot deformities are confused with “gout” is incredibly common. That gout may co-exist with hallux valgus or other distortion we readily admit, but this does not absolve us of our responsibility—correction of the static deformity. Combine this, if you will, with constitutional treatment if there be evidence, i.e., tophi, of a “gouty” diathesis, but, we repeat, correct the mechanical defect. For gout may come and go, but static errors remain. In so doing, the victim will be saved much preventable suffering, and, for aught known to the contrary, the removal of irritation and local congestion may haply minimise the chances of subsequent gouty outbreaks.
While primary attacks are in the vast majority of instances localised to the foot, if not actually to the toe, it is well to recollect that very rarely the knee, the wrist, elbow, or ankle may be the chosen spot. In such cases there is need for exceptional caution before committing oneself to a diagnosis of gout. Certainly not until all other known causes of acute arthritis of monarticular type have been excluded.
If in the knee or wrist, any possibility of injury or strain should be thoroughly canvassed. To make assurance doubly sure, a radiograph should always be taken. Specific infective forms of arthritis then call for careful elimination—i.e., gonococcal, etc. If there be no history of such, a painstaking search should be made for any local foci of infection, e.g., mouth and accessory cavities. If any be found, they should be radically treated, as it is much more likely that the arthritis is due thereto than to gout.
If, notwithstanding a meticulously careful investigation, no cause can be assigned, we may entertain the possibility of its being gout, the more legitimately if the subject be a middle-aged man coming of gouty ancestry and exhibiting himself tokens of this diathesis, i.e., tophi. It would be confirmatory, too, if, apart from its exceptional localisation, the joint disorder in its course conformed to that typical of gout in the toe, in other words if it was of sudden nocturnal onset, showed marked daily remissions in temperature and pain, responded swiftly to the action of colchicum, and was not protracted beyond the usual week or ten days.
Sir Hale White, discussing the diagnosis of acute gout of unusual localisation, remarks: “The real difficulty in acute cases comes when it is suggested that an acute arthritis with pyrexia and swelling and redness of a joint other than that of the great toe is caused by gout. I have recently seen the difficulty in one patient in the wrist, in another in the knee. Such cases, if they are not gout, are some bacterial arthritis.”