Fig. 159.—Hallux Rigidus and Flexus in a boy æt. 17. There is a suppurating corn over the head of the first metatarsal bone.
As the disease progresses, the toe is drawn towards the sole and becomes permanently flexed—hallux flexus—and any attempt at dorsiflexion is attended with pain.
The condition is met with chiefly in adolescent males, is nearly always associated with flat-foot, and is then usually bilateral. The patient's gait, in addition to having the characteristic features associated with flat-foot, is peculiarly wooden and inelastic, as instead of rising on the balls of the toes with each step, he puts down and lifts the sole as if it were a rigid plate. The pain is increased by walking. The boot tends to become worn away at the point of the toes and at the posterior edge of the heel, and the usual crease across the dorsum is absent.
On dissection it is found, especially in hallux flexus, that the inferior portions of the collateral ligaments are contracted, and that the cartilage of that part of the head of the metatarsal which is exposed on the dorsum is converted into fibrous tissue; there may also be other changes characteristic of arthritis deformans. Bony ankylosis has not been observed.
Treatment.—In early cases, great benefit results from measures directed towards the cure of the accompanying flat-foot, and especially the wearing of the support of the anterior arch devised by Scholl. If the joint of the big toe is painful and sensitive, absolute rest should be enforced until these symptoms have disappeared. The patient must wear a properly shaped boot with a pliable sole, and be instructed how to manipulate and exercise the toe. Later, when the toe is already rigid or flexed towards the sole, the above treatment is not feasible. It is then best to correct the deformity either by wrenching the toe into the dorsiflexed position, under anæsthesia, and fixing it with a plaster-of-Paris bandage; or, when this is impossible, by excising the articular end of the metatarsal bone and interposing a layer of fatty or bursal tissue between the distal end of the metatarsal and the base of the first phalanx. When these measures are impracticable, the suffering may be relieved by inserting in the boot a rigid metal plate which will prevent any attempt at dorsiflexion in walking.
Hammer-toe.—This is a flexion-contracture which generally involves the second, but sometimes also other toes. It may be congenital and inherited, but usually develops about puberty, and is then, as a rule, bilateral, and often associated with flat-foot.
The first phalanx is dorsiflexed, and the second is plantar-flexed, while the third varies in its attitude, sometimes being in line with the second ([Fig. 160]), sometimes even more plantar-flexed, and sometimes dorsiflexed. When the second toe alone is affected, as is commonly the case, it is partly buried by those on either side of it, only the knuckle of the first inter-phalangeal joint projecting above the level of the other toes ([Fig. 160]). The skin over the head of the first phalanx being pressed upon by the boot usually presents a corn, under which a bursa forms ([Fig. 161]). Both the corn and the bursa are subject to attacks of inflammation, which cause suffering and disability in walking. The soft parts at the distal extremity of the toe are flattened out by contact with the sole of the boot—hence the supposed resemblance to the head of a hammer.
Fig. 160.—Hammer-toe.