This section is from the book "Applied Anatomy: The Construction Of The Human Body", by Gwilym G. Davis. Also available from Amazon: Applied anatomy: The construction of the human body.
This sometimes exists as a pure form but it often accompanies varus and sometimes valgus. It is caused by a paralysis of the extensor muscles. The tendo calcaneus is contracted and the patient walks on the toes. By division or lengthening of the tendo calcaneus and forcible flexion of the foot the
Fig. 599. - Talipes calcaneus.
Fig. 600. - Talipes cavus heel may be brought down but the foot will "flop in a more or less flail-like condition from the leg. To remedy this either an apparatus is employed or sometimes the peroneal muscles or some of the flexor tendons are brought forward and the effort made to have them fulfil the function of the paralyzed extensors, which latter may also be shortened (Fig. 598).
These result from paralysis of the muscles of the calf or of most of the flexor and extensor muscles (Figs. 599 and 600).
If the calf muscles are paralyzed the contraction of the tibialis anterior and tibialis posterior pull up the arch and the contraction of the flexor brevis digitorum pulls the pillars closer together, therefore the heel descends, the arch ascends, and the plantar ligaments contract. If the extensor muscles are also paralyzed the toes drop and the anterior deformity is increased.
The treatment of this condition is as yet not entirely settled. The plantar fascia must be divided and the pillars of the arch separated and the arch depressed by forcible manual or instrumental means. To retain the foot in its corrected position the tendo calcaneus is sometimes shortened. Jones makes an arthrodesis (ankylosis) of the midtarsal and ankle-joints; Whitman excises the astragalus, pushes the foot back, and transplants the peroneal and posterior tibial tendons into the os calcis. The writer makes a transverse section through the sub-astragaloid joint, pushes the foot back, and if necessary transplants the peroneal and posterior tibial tendons into the os calcis.
Hallux valgus is a subluxation of the big toe outward. There is usually a deformity of the bone, the joint surface of the head of the first metatarsal being inclined obliquely out. As the toe becomes displaced outward the extensor hallucis longus by its contraction tends to increase the deformity. On the side of the head of the protruding metatarsal bone a bursa develops and becomes painful, forming a bunion. This bursa sometimes suppurates (Fig. 601).
In some cases hallux valgus is due apparently to ill-shaped shoes, but in many cases, and these the worst, a rheumatic-gouty condition is the main factor. In treatment the articular surface of the head of the first metatarsal bone is first resected. This enables the toe to be brought straight. To keep it straight the tendon of the extensor hallucis is displaced inward so that by its contraction it keeps the toe from again going outward.
Fig. 601. - Hallux valgus, showing the position of the bones.