Monarticular Gout in Large Articulation a Rarity
Given a chronic arthritis of one of the larger joints, say the ankle, knee, or elbow, we should be careful not to jump too readily to the conclusion that it is of “gouty” nature. The more obscure it appears the more need for caution. Needless to say, if the objective changes be but minimal and the condition be, so to speak, practically a mere arthralgia, there rests upon us the paramount necessity of careful discrimination before labelling it as “gouty” in kind.
Thus, if it be the knee, it may be a referred pain due to hip disorder, e.g., osteoarthritis or tuberculous disease, or it may be symptomatic of an inflammatory process, or, having regard to the usually mature or advanced age of the subject, it may be a neoplasm in the bones.
On the other hand, suppose the subject come complaining not much of pain in his joint, but more troubled because of its enlargements. If now on examination we find also that there is little or no tenderness, but simply a condition of peri-articular thickening or intra-articular effusion, what shall be our method of procedure? Certainly not to leap forthwith to the conclusion that it is gouty. No, not even if he exhibit tophi in his ears.
Now, as to pain and tenderness, it is a blessed feature of gouty arthritis that, generally speaking, in the chronic forms pain becomes much attenuated. But let us at the same time recollect that syphilitic arthritis, both secondary and tertiary, is relatively painless. But it is the much rarer tertiary form, be it remembered, which is usually monarticular. By the bye, too, we should never forget that a Charcot’s joint is also painless.
Coming now to the objective phenomena, is the case predominantly one of peri-articular infiltration or intra-articular effusion? As to the former, while you never know, still tuberculous joint disease is exceptionally rare at the age at which we usually meet gout. On the other hand, gummatous synovitis, with or without osteoperiostitis, is occasionally met with. It is just such a case as this that may be confounded with gout, the irregular lumpy thickening of the sub-synovial tissues with effusion being wrongly attributed to a gouty process with uratic deposits. Do not be misled if a history of injury be forthcoming in such cases, for it is not uncommon and may be given in good faith.
Now what if synovial effusion of chronic or recurring form be the striking objective feature of the case under review? In this event always recollect that of all the causes of monarticular disorder injury is far and away the most frequent. Not a few cases of monarticular joint disease come annually to the Royal Mineral Water Hospital, Bath, under the diagnosis of “gout” and “rheumatism.” But in all too many the symptoms are referable in truth to ligamentary strain, displaced cartilage, or foreign bodies, lesions always to be sought for and excluded in monarticular joint affection. Duckworth has it that hydrarthrosis is met with in chronic articular gout, in his deforming variety. He states that “hydrarthrosis is less commonly due to gout than to rheumatism,” but, we would remark, apart from traumatic lesions, more commonly due to gonorrhœa or syphilis than to either of them.
But the reader may say, this dissertation notwithstanding, Where does gout come in? Precisely so, and if his experience tallies with mine, he will find that chronic articular gout localised in one of the larger joints, and one only, is exceptionally rare. Personally, I should never feel justified in making the diagnosis unless I had elicited a history of (1) recurring classic outbreaks in the great toe with (2) an absence of traumatic infective and nerve arthropathies and, on the other hand, (3) demonstrable existence of uratic deposits in situ in the peri-articular tissues, the cartilage or bones as revealed by skiagraphy, or in the related bursæ.
In conclusion, if all these various pitfalls have been avoided, it will almost without exception be found that the final differentiation in doubtful cases will rest between gout and osteoarthritis; and in the vast majority, I had almost said all, it is the latter morbid process that will be found responsible.
This all too lengthy disquisition will not have been in vain if it instil caution. For it is in the monarticular types of joint affection that errors of catastrophic proportion occur more commonly than in any other form of joint disorder.