Separation of the lower epiphysis of the tibia is not common. It occurs most frequently between the ages of eleven and eighteen, as a result of forcible eversion or inversion of the foot. It is usually accompanied by fracture of the diaphysis of the fibula ([Fig. 98]), and is not infrequently compound. When the epiphysis is displaced to one side, the deformity is characteristic. In rare cases the growth of the tibia is arrested, the continued growth of the fibula causing the foot to become inverted. The treatment is the same as for Pott's fracture.
Fracture of the talus usually occurs as a result of a fall from a height, the bone being crushed between the tibia and the calcaneus. It is usually associated with other fractures, and is sometimes impacted, the foot assuming the position of equino-varus. The diagnosis is only to be made by exclusion, or by the use of the Röntgen rays. In interpreting radiograms of injuries in this region, care must be taken not to mistake the os trigonum tarsi for a fracture. In uncomplicated cases, the treatment consists in immobilising the foot and leg in a poroplastic splint and applying massage. In comminuted and in impacted fractures with persistent deformity, complete excision of the bone yields good results.
The calcaneus is most frequently broken by the patient falling from a height and landing on the sole of the foot, and the injury may occur simultaneously in both feet.
The primary fracture is usually longitudinal, passing through the facets for the talus and cuboid, and from this various secondary fissures radiate; the cancellated tissue is much crushed, so that the whole bone is flattened out. In spite of the great comminution, it is often impossible to elicit crepitus, as the fragments are held together by the investing soft parts. In other cases the foot may feel like “a bag of bones.” The lesion is often mistaken for a fracture of the lower end of the fibula, or is not diagnosed at all. The chief clinical feature is pain on movement of the foot, or on attempting to walk; the foot appears flat, and the hollows on either side of the tendo Achillis are filled up. In many cases there is a persistent tenderness which delays restoration of function for some months, but the ultimate result is usually satisfactory.
Treatment.—In simple comminuted fractures the patient should be anæsthetised, and the foot moulded into position, care being taken to restore the arch in order to avoid any tendency to flat foot. The foot is supported on a pillow, and to prevent stiffness, massage and movements of the ankle and tarsal joints should be commenced without delay.
Compound fractures confined to the calcaneus may be treated on conservative lines, but if associated with other injuries of the foot they may necessitate amputation.
The tuberosity of the calcaneus, into which the tendo Achillis is inserted, is sometimes separated by forcible contraction of the calf muscles, or from a fall on the ball of the foot. The separated fragment may be pulled up for a distance of 1 or 2 inches, and the rough surface from which it has been torn may be recognisable. The patient may be able to walk immediately after the accident, although with difficulty; or he may have pain for many months.
A good functional result is usually obtained by relaxing the calf muscles and fixing the foot in the position of extreme plantar flexion with the knee flexed, but in some cases it is advisable to peg the fragments, either through the skin or after exposing them by operation.
The other bones of the tarsus are rarely fractured separately. The tuberosity of the navicular is sometimes torn away by violent traction on the ligaments attached to it.
Fractures of the metatarsals and phalanges usually result from direct violence, such as a crush of the foot, in which the soft parts are severely damaged. The use of the Röntgen rays has shown, however, that certain painful conditions in the foot following comparatively slight injuries, such as kicking a stone, are due to a fracture of one of the metatarsals or phalanges.