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convexity presenting outwards.

On the posterior half of its

external face an articular facet is formed for the malleolus

externus.

The cuboid bone assumes a conical shape, the apex presenting towards the sole of the foot; it is separated by a considerable interval from the os calcis. This bone is thought to be so important by Dr. Little in preventing the restoration of the foot in inveterate adult congenital varus, that he says, "the treatment might well be commenced in robust subjects by ablation of the os cuboides, which, in preventing the unrolling of the foot, acts as the keystone of the inverted arch." The operation of ablation of the cuboid has been performed by Mr. Solly; inversion of the foot was overcome, and a useful limb was gained. I doubt whether this operation is ever necessary under forty years of age, and I should only deem it justifiable when other means had failed.

The cuneiform bones are less affected by pressure than by impaired nutrition; they are relatively smaller than in their normal condition, but their forms are little changed. They are rotated en masse with the anterior portion of the foot the first cuneiform bone, however, is sometimes found to be rotated with the scaphoid by the tibialis posticus.

;

The tibia and fibula undergo atrophy, and the malleolus internus is shorter and more flattened than natural; it presents an articular facet, which corresponds with that of the scaphoid bone.

All the bones of the foot and leg become atrophied, and as age advances, degeneration of the bones takes place: this change, however, is more frequently connected with paralytic distortion than with the ordinary form of congenital varus. Concentric atrophy is, perhaps, more

1 On the Deformities of the Human Frame,' p. 305, 1853.

commonly seen; the periosteum becomes loosely attached to the bone, and the endosteum is softened and attenuated.

These changes are incident to age. Also, anchylosis of the tarsus, rarely, occurs, or excrescences form on the head of the astragalus, for instance, which impede motion and prevent the restoration of the limb. But the change which is perhaps more than any other important, and which is common in long-continued distortion, is loss of elasticity in the ligaments. The rigid shortening of the ligaments is not unfrequently a serious impediment to the restoration of the shape of the foot in mature manhood, and greater than the changes incident to the bones.

The ligaments which are especially rigid and shortened, are-lig. deltoideum, plantare calcaneo-scaphoideum, calcaneo-cuboideum, plantare naviculare-cuboideum, plantare commune; and those which are most extended are-lig. fibulæ anterius, medium, et posticum, membrana capsularis ossis navicularis et capitis tali, and those on the dorsum, between the astragalus, scaphoid, and cuneiform bones. The plantar fascia, also, is always retracted.

Every muscle of the leg and foot is directly or indirectly affected, being either retracted or extended. Those which · are most retracted are-M. gastrocnemius, soleus, tibiales, anticus et posticus, flexor longus digitorum, plantaris, abductor pollicis, transversus pedis, flexor brevis minimi digiti, flexores, longus et brevis, pollicis; and those which are most extended are-M. peronei, longus, brevis, et tertius, extensor longus digitorum, extensor brevis digitorum, abductor minimi digiti.

At an early period of distortion, the muscles alone are retracted, and the blood-vessels accommodate themselves by a series of curves to the distorted position of the limb. But

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after the lapse of years, when structural change and shortening have resulted, the vessels and nerves likewise are found to be essentially shortened. At the same time that the muscles undergo structural change, the fasciæ lose their glistening appearance; the ligaments soften and lose their elasticity; the tendons diminish in size, and the bloodvessels in calibre; the nerves become as though reduced to their neurilemma; and the skin no longer retains its smoothness and elasticity.

The following is the report of Cruveilhier of a dissection of congenital varus from a female, aged 41, the limb having been injected through the popliteal artery:

"The thigh on the side of the distorted foot was nearly the same size as the other thigh, but the leg was atrophied. The subcutaneous layer of fat was of considerable thickness. The skin was hard, the dermis being thickened; and over the tuberosity of the calcaneum, which projected considerably, the cuticle was deposited in several layers. An irregular synovial capsule allowed the skin to move freely over the tuberosity. The skin of the sole of the foot was thin, as that which has not been subjected to friction. The aponeurosis of the leg was much thinner than usual, and had in part lost its glistening appearance. The nerves, especially the muscular branches, were extremely small, as though reduced to their neurilemma. The tibial arteries had not half their usual calibre, and only one muscular branch was injected. The veins, in like manner, were diminished in size. All the muscles had passed into a state of fatty degeneration-the tibialis anticus, extensor longus digitorum, the peronei, longus et brevis, the soleus, and the external head of gastrocnemius; and the tendons themselves were very much attenuated. The tendo Achillis was certainly not half the size of that of the other leg; and the aponeurosis, having undergone a similar amount of atrophy, showed that exercise is as necessary to the tendons and fasciæ as to the muscles. The traction which the muscles make on their tendons during contraction is the exercise that is requisite for them, and the distension which is caused by the same contraction is that which is necessary to the aponeuroses.' Anatomic Pathologique,' tome i, livraison 2, 1829-35.

1

TALIPES VALGUS.-ẞlatoos, valgus, plattfuss, splay-foot, pied-plat, stréphexopodie.

Valgus is, in some sort, the reverse of varus, inasmuch as the adductor muscles are retracted in varus, but the abductors, in valgus.

In valgus the foot is everted, the arch of the foot is lowered or lost, and a convex surface may present instead of the normal arch; the outer edge of the foot is raised, and the plantar surface is inclined outwards; the malleolus internus is consequently rendered unusually prominent, and brought nearer to the ground; the toes are extended, and the knee is inclined inwards. Such are the general characters of valgus.

Three grades of distortion may be distinguished.

In the first degree the peronei muscles are alone retracted, through which the motion of the ankle-joint is impeded, and the foot is everted and rotated outwards. This is a rare form of congenital affection, and far less common than the second degree.

The second degree is that which usually exists as congenital valgus. (Figs. 9 and 10.) M. peronei, longus, brevis Fig. 9.

et tertius, extensor longus digitorum, gastrocnemius, and soleus, are retracted. Very rarely the extensors of the foot are not retracted.

In the third degree, in addition to the muscles above mentioned, M. tibialis anticus, extensor proprius pollicis, and

Fig. 10.

abductor minimi digiti, are also retracted.

In this grade of

valgus the muscles of the calf of the leg are always retracted, and the heel is in consequence raised; but the anterior portion of the foot is flexed on the leg by the action of the muscles on the anterior surface of the leg; consequently the ankle-joint is locked, the arch of the foot is destroyed, and the plantar surface presents a convex, instead of its normally concave surface. The dorsum of the foot is hollowed out on its outer aspect, and lies in contact with the external and anterior surfaces of the leg. (Fig. 11.) This degree of distortion is rare, and when it exists in both feet is usually combined with monstrosity. Extreme grades of distortion,

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