This group includes the conditions known as hammer toe, hallux flexus, and some of the lateral versions of the toes.
HAMMER TOE.
This complaint may be described as a permanent flexion from the straight line at either or both of the inter-phalangeal joints, without paralysis of muscles, unattended with any primary degenerative or inflammatory disease of the articular structures, and essentially confined in origin to the period of active growth. Some precision of definition is necessary to exclude similar deformities of wholly different pathological nature.
Hammer toe was known long before it became the subject of scientific observation. According to Dr. Cohen,[8] the first printed description was that by a French surgeon named Laforest, in a volume published in 1782, and entitled “L’Art de Soigner les Pieds”; but Laforest was the successor of one Rousselot, who thirteen years earlier wrote a book to which he gave the formidable name of “La Toilette les Pieds, ou Traité de la Guérison des Cors, Verrues, et autres Affections de la Peau, et Dissertation abrégé sur le Traitement et la Guérison des Cancers.” In this essay a flexion of the toes attributed to the use of short shoes is alluded to with sufficient clearness to make it probable that Laforest had succeeded to the ideas as well as to the practice of his predecessor. The first account, however, with any pretensions to science, was that given by Boyer in 1822.[9] Since that time the subject has been discussed repeatedly in France, and within the last few years has been brought forward twice in England, at the Clinical Society in 1887, and at the Medical Society in 1889.
The deformity is found in both sexes, but appears to be somewhat more frequent in the male (three to two). The influence of age is very strongly marked. The condition invariably begins within the developmental period, and may show itself at any time between birth and adult life, but most frequently attracts the notice of the patient for the first time during the third quinquennial period. Amongst a number of incipient cases seen at Hanwell not more than one-tenth were under twelve years of age, the little toe being usually the seat of the earlier manifestations. It is said to be occasionally congenital. So far as my own observations go, neither class, occupation, nor constitutional condition, appears to have any share in its production.
It has long been a popular as well as a medical opinion that the deformity is handed down by inheritance. Even Laforest, who contests the belief, says, “Je m’entends souvent dire que l’on est né avec un doigt ainsi; que c’est un doigt de famille.” Boyer asserted that it was frequently inherited, and Blum and others have adduced examples in support of this view. In a paper read before the Clinical Society in 1887, I referred to a history in four cases out of twenty-two which had the same bearing; and other striking examples have since been brought forward by Mr. Adams. In fact, some evidence of the influence of the hereditary principle may be traced in at least a fourth of the examples that come under notice, and is particularly frequent and clear amongst patients of the educated classes.
The subjoined pedigree of a family in which the affection has arisen, illustrates the descent through four generations. It was noted that the children attacked were those who presented most resemblance in feature and temperament to the grandfather. The deformity usually appeared about the age of four, and was confined to the second toe. “Double-jointed” thumbs were also an inheritance in the family. In another example the condition developed in five children out of eleven. Here too there was a history of “double-jointedness” in the fingers and thumb, extending through three generations; and an aunt on the male side was also the subject of hammer finger. This association of hammer toe with other developmental irregularities is significant enough to deserve attention. In addition to the instances mentioned, there are amongst the seventy-three surgical cases on my list three accompanied by hallux flexus, and one with retraction of both little toes; and there is little doubt that coincidences of a like kind would more frequently be found were it always possible to ascertain the facts by inquiry.
Seat of attack.—In surgical cases the toe most commonly affected is the second. In my list of 73 patients who had applied for treatment, this digit was affected in all but four, while the third was attacked in five, the fourth in one, and the fifth in three cases. In one instance the affection of the third toe was symmetrical, each afforded only a single example; but if all cases of contraction of the joint for 30° or more be counted without reference to symptoms, the condition is far more frequent in the little toe than in the others. Thus in an examination of a series of 800 children under sixteen years of age the little toe was found to be involved in forty-one cases, nearly all of which were double, while the second toe was affected in six only, and the third toe in five. It may be noted also that the projection of the extremity of the second toe beyond that of the first—a condition regarded as a type by the ancient sculptors—was present in only three instances. This is confirmed by Professor Flower, who failed to find a single instance in many hundreds of children.