carried along with it, the internal malleolus being moved forwards, and the external backwards. The superior articular surface of the bone is imperfectly covered by the tibia; indeed, it may remain entirely uncovered by the tibia, and be thrown forward on to the dorsum of the foot. The astragalus being strongly articulated with the os calcis, is slightly rotated together with it: it undergoes consequently a twofold displacement; first, in its long axis, through its attachments with the calcaneum, and secondly, in its vertical axis.

The scaphoid bone is drawn inwards and upwards, and its tubercle may be in contact with the internal malleolus. And the cuboid, with the cuneiform bones, as well as the metatarsus and the phalanges, necessarily follow in the abnormal direction of the other bones of the foot.

The muscles which are principally concerned in giving rise to talipes varus are, tibiales, anticus et posticus, flexor longus digitorum, gastrocnemius, and soleus.

The plantar fascia is an important agent in the increase of distortion. It is very rarely alone shortened and without affection of the muscles, but it generally becomes secondarily affected; then it diminishes the length of the foot, and the span of the arch of the foot. It is, however, occasionally alone shortened at birth, but more frequently there is combined with it retraction of the tibialis anticus.

The tibiales are necessarily, from their attachments, mainly instrumental in the production of varus; they invert the anterior portion of the foot, and raise its inner edge from the ground: while the muscles of the calf of the leg raise the posterior extremity of the os calcis. It is this combined action of the extensors and adductors of the foot, together with the traction which is made on the calcaneo

scaphoid ligament, that causes rotation on its axis of the os calcis. And the astragalus is necessarily rotated with it; and also, through the elevation of the os calcis, is thrust forward on to the dorsum of the foot, and gains an oblique direction as regards the malleoli. The positions of these bones are due solely to muscular retraction; and their positions vary as muscular retraction is considerable or otherwise.

In the fourth degree of varus, the tarsal bones are not only twisted on their axes, but they are also sometimes wanting in development and are malformed. When distortion is induced at an early period of gestation, muscular retraction appears to be greater than when it occurs at a later period. The cartilages, then, accommodate themselves to the distorted position of the limb, and irregularities of form occur through abnormal pressure. These malformations of the tarsal bones occur only in severe forms of congenital varus ; and in these instances some abnormality of the brain or spinal cord is generally found to coexist. In these cases, and also when distortion is less complicated, the patella is not unfrequently retracted above its usual position it may be drawn up on the outer side of the thigh to the extent of from two to three inches. Occasionally, it is scarcely more than elementary in its development; once I have found it reduced to one eighth of its normal size; and in one instance it was absent. The following is the case, which I copy from my note-book :

:

"Oct. 1855.-H. T., æt. two months, was born at the eighth month of utero-gestation. Remained during three days after birth almost inanimate. From that time to the present has daily been convulsed, and several times in the course of the day. Is a poor, little, sickly, puny child.

"There is valgus of the left foot, of the third degree; and varus of the right, of the second degree, together with powerful retraction

of the quadriceps extensor cruris, through which the leg is slightly bent forwards upon the thigh. After very careful examination, I was unable to discover any trace of a patella. They were both absent."

Duval mentions an instance in which the patella was absent, as follows:

"There is at present in my Orthopaedic Institution a young child from Clermont-Ferrant, sixteen months old, who was born with extreme varus of the right foot, and equally well-marked equinus of the left. The flexor muscles are strongly retracted, and the toes are flexed on themselves; the tibio-tarsal, the tarsal, and the tarsometatarsal articulations present almost a tetanic rigidity. In this child there is a development that I have never before observed, namely, absence of the patella."1

A spastic condition of the extensors of the leg is not an uncommon condition, together with the most severe form of club-foot; the knee can then only be partially bent, and the leg immediately returns to its extended position.3

Rotation of the tarsal bones is in rare instances so great, that their replacement becomes exceedingly difficult, yet dislocation does not occur, but rotation on their axes only. An instance of dislocation is, however, recorded, and the specimen is shown in the Strasburg Museum. The astragalus is dislocated inwards and forwards, and displaced transversely, with its posterior surface in contact with the malleolus externus.3

1 Op. cit., p. 95.

2 Occasionally, retraction of the extensors of the leg continues to exist for many years. I have known it to exist at thirty years of age equally as in infancy. Congenital varus may be removed, and this distortion be suffered to remain, as, indeed, usually happens. I have once divided, with great advantage, the Sartorius at its origin, and the internal head of the rectus, in a case of this kind, where motion was impeded by retraction of the extensor muscles: the thigh was flexed on the trunk, and the leg was forcibly and rigidly extended. 3 Vide Held, 'Diss. sur le Pied-bot,' 1836.

3

When the child begins to walk and to bear the weight of the body on the feet, important changes commence. The outer edge of the foot being alone in contact with the ground, a callosity, composed of fat and cellular tissue, is developed over the cuboid bone and the fifth metatarsal bone, for the protection of the skin, or over that portion of the outer edge of the foot which is in contact with the ground. A bursa mucosa is formed between the cushion and the bones, and a second bursa is frequently found between the cushion and the skin. These bursæ are apt to inflame through prolonged pressure; ulceration of the skin also occasionally takes place, and the callosity may be in part or wholly destroyed.

Pressure on the outer edge of the foot, to which the development of the callosity is due, occasions also rotation of the fifth metatarsal bone into the sole of the foot; for the surface being narrow for the support of the superincumbent weight, and the bone insufficiently supported, it yields and is pressed into the sole of the foot the fourth metatarsal bone then, together with the fifth, the cuboid bone, and the os calcis, form the base of support.

Fig. 7.

And in

like manner the fourth metatarsal bone may yield. In this way the transverse arch of the foot, which previously was unaffected, is compressed. (Figs. 7 and 8.) Now, it is not the outer edge of the foot alone which is in contact with

Fig. 8.

the ground, but the dorsum. And distortion may even be increased beyond that which is now described. The weight of the body is now no longer transmitted to the ground through an arch, as in the normal condition of parts, but through a solid pile of bones; and, consequently, alterations in form are produced by attrition of the bony surfaces one upon another.

The scaphoid is, perhaps, more altered than any other tarsal bone in a case of long-standing congenital varus, being wedged in between the inner malleolus, the astragalus, the cuboid and the cuneiform bones. It undergoes atrophy through pressure (indeed, all the bones of the foot undergo atrophy, either through pressure or impaired nutrition), a new facet is formed for articulation with the inner malleolus, and occasionally this bone is found almost translucent, through the pressure of the head of the astragalus.

The os calcis becomes curved in its long diameter, the