Chapter 21. The Ankle and Foot

At the completion of this chapter, the reader will be able to:

1. Describe the anatomy of the joints, ligaments, muscles, and blood and nerve supply that comprise the ankle and foot complex.

2. Describe the biomechanics of the ankle and foot complex, including the open- and close-packed positions, normal and abnormal joint end-feels, kinesiology, and the effects of open- and closed-chain activities.

3. Outline the purpose and components of the tests and measures of the ankle and foot complex.

4. Perform a detailed examination of the ankle and foot complex, including palpation of the articular and soft tissue structures, range-of-motion (ROM) testing, passive articular mobility tests, and stability tests for the ankle and foot complex.

5. Discuss the significance of the key findings from the tests and measures.

6. Evaluate the total examination data to establish a physical therapy diagnosis.

7. Describe the significance of muscle imbalance in terms of functional muscle performance and the deleterious effects on the lower kinetic chain.

8. Develop self-reliant examination and intervention strategies.

9. Describe the intervention strategies based on clinical findings and established goals.

10. Apply manual techniques to the ankle and foot complex, using the correct grade, direction, and duration.

11. Incorporate appropriate therapeutic exercises into the intervention progression.

12. Evaluate intervention effectiveness in order to progress or modify the intervention.

13. Plan an effective home program and instruct the patient in same.

The ankle and foot is a complex structure of 28 bones (including two sesamoid bones) and 55 articulations (including 30 synovial joints), interconnected by ligaments and muscles.

The foot has undergone a number of evolutionary adaptations, which make it very effective for bipedal locomotion. 1First, the foot has become plantigrade, which allows most of the sole to be a weight-bearing surface. Second, the great toe has come to lie in a position with the other toes and, because of the relative immobility of the first metatarsal at the metatarsophalangeal (MTP) joint, is now relatively nonprehensile. Third, the metatarsals and phalanges have progressively shrunk and become small in comparison to the hypertrophied tarsus. Last, the medial side of the foot has become larger and stronger than that of any other primate.

The ankle joint sustains the greatest load per surface area of any joint of the body. 2Peak vertical forces reach 120% of body weight during walking and they approach 275% during running. 3The joints and ligaments of the ankle and foot complex act as stabilizers against these forces and constantly adapt during weight-bearing activities, especially on uneven surfaces. It is estimated that an average 180-lb man absorbs 76.2 tons on each foot while walking 1 mile and that the same man absorbs 121.5 tons per foot while running 1 mile. 4Approximately 60% of this weight-bearing load is carried out by the rearfoot, and 28% by the metatarsal heads. 5,6Although the ankle and foot complex normally adapts well to the stresses of everyday life, sudden or unanticipated stresses to this region ...