When you finish this chapter you will be able to:
Briefly describe the anatomy of the foot.
Explain the process of injury assessment for the foot.
Formulate steps that can be taken to minimize foot injuries.
Identify the causes of various foot injuries commonly seen in athletes.
Describe the appropriate care for injuries to the foot.
The human foot must function both to absorb forces and to provide a stable base of support during walking, running, and jumping. It contains 26 bones (7 tarsal, 5 metatarsal, and 14 phalangeal) that are held together by an intricate network of ligaments and fascia and moved by a complex group of muscles (Figure 14–1). The tarsal bones that form the ankle include the talus and calcaneus. The navicular, cuboid, and three cuneiform bones form the instep of the foot.
Bony structure of the foot. (Modified from Van De Graaff, K: Human anatomy, ed. 6, Dubuque, IA: McGraw-Hill Higher Education, 2002.)
The foot is structured, by means of ligamentous and bony arrangements, to form several arches. The arches assist the foot in supporting the body weight and in absorbing the shock of weight bearing. There are four arches: the medial longitudinal, the lateral longitudinal, the metatarsal, and the transverse (Figure 14–2).
Arches of the foot: (A) Metatarsal and transverse arches. (B) Medial longitudinal arch. (C) Lateral longitudinal arch.
The metatarsal arch is shaped by the distal heads of the metatarsals. The arch stretches from the first to the fifth metatarsal. The transverse arch extends across the transverse tarsal bones and forms a half dome. The medial longitudinal arch originates along the medial border of the calcaneus and extends forward to the distal head of the first metatarsal. The main supporting ligament of the medial longitudinal arch is the plantar calcaneonavicular ligament, which acts as a spring by returning the arch to its normal position after it has been stretched. The lateral longitudinal arch is on the lateral aspect of the foot and follows the same pattern as the medial longitudinal arch. It is formed by the calcaneus, cuboid, and fifth metatarsal.
Plantar Fascia (Plantar Aponeurosis)
The plantar fascia is a thick white band of fibrous tissue originating from the medial aspect of the calcaneus and ending at the distal heads of the metatarsals. Along with ligaments, the plantar fascia supports the foot against downward forces ...