Apart from the simultaneous incidence of gout and fibrositis in the same subject, it is equally certain that the victims of a “gouty” heritage are unusually prone to develop fibrositis.
Thus, in a series of 1,000 cases hereditary or acquired gout was present in no less than 281—viz., a percentage incidence of 28·1. While this taint was more in evidence in fibrositis of the joints, it obtained appreciably in regard to all muscular types of the affection, more especially lumbago, its influence also being very obvious in the case of sciatica and other types of nerve sheath involvement.
In light of this, we must admit being somewhat nonplussed by those who confidently affirm that “gout” plays little or no part in the production of “fibrositis.” Speaking from an extensive experience, we confidently believe the reverse is the case, and that the gouty element is but too frequently overlooked in examples of this affection.
Approaching another aspect of this vexed question of the relationship of gout, what of the ambiguous attitude of those who, while denying it any share in the causation of lumbago and other types of muscular fibrositis, yet at the same time attribute to gout an important etiological rôle in the allied conditions sciatica and brachialgia?
Thus, they maintain that the fleeting attacks of lumbar fibrositis or lumbago which ensue after dietetic indiscretions have no relation to gout, but are simply indicative of some digestive disability on the part of the individual for certain articles of diet. Hardly to our mind a satisfactory mode of differentiation; much less can it be held to put out of court the influence of gout. For are not the gouty precisely the very persons who display this inability to cope satisfactorily with unusual or excessive meals? Hence the frequency with which in their instance attacks of lumbar fibrositis, often transient, almost invariably ensue when any unwonted excess of purin-containing food has to be disposed of, and especially when at the same time katabolic changes have been stimulated in the body by the ingestion of alcohol, not necessarily excessive in amount.
That the lumbar regions should have been singled out is the more remarkable, for, if there be one form of fibrositis more than another prone to be associated with gout, it is precisely lumbago.
Our difficulty, moreover, in appreciating the cogency of this plea for excluding the influence of gout in muscular fibrositis is the more accentuated in that those who advocate it claim that this very gout is the salient etiological factor in sciatica and brachialgia.
This position is untenable, and for the following reasons: the pathological lesion in both instances is the same—viz., fibrositis; in lumbago and deltoid rheumatism it implicates the sheaths and interstitial tissues of the muscles, in sciatica and brachialgia the similar investments of the nerves.
Strictly speaking, therefore, any differentiation that we can effect between muscular and neuralgic types of fibrositis is perforce merely topographical. To draw etiological distinctions is well-nigh impossible, for the very continuity of the fibrous tissues favours the passage of one type into the other. Hence clinically we find that the bulk of our cases of sciatica are preceded by lumbago, and similarly many cases of brachial neuralgia or neuritis develop by extension out of a pre-existing deltoid fibrositis.