ABSTRACT
The lower extremities, each composed of a thigh, leg, and foot for the purposes of this chapter, are the primary mechanisms by which humans maintain upright posture and move their bodies. During quiet stance, they support the body with subtle anterior/posterior and medial-lateral movements, whereas during locomotion, they guide the body through a complex mechanism of weight transfer, ground impact, and propulsion. Within
CONTENTS
10.1 Introduction ........................................................................................................................ 265 10.2 Anatomy of Lower Limb ................................................................................................... 266
10.2.1 Hip ........................................................................................................................... 266 10.2.2 Knee ......................................................................................................................... 268 10.2.3 Foot and Ankle ....................................................................................................... 269
10.3 Structure and Function of Lower Limb .......................................................................... 273 10.3.1 Hip ........................................................................................................................... 273 10.3.2 Knee ......................................................................................................................... 275 10.3.3 Foot and Ankle ....................................................................................................... 276
10.3.3.1 Motion of the Joints of Foot and Ankle................................................277 10.3.3.2 Arch of the Foot: Windlass Mechanism and Midtarsal
Joint Locking ............................................................................................ 278 10.3.3.3 Foot Type .................................................................................................. 279
10.4 Locomotion Biomechanics ................................................................................................280 10.4.1 Overview of Human Locomotion ....................................................................... 281 10.4.2 Link-Segment Gait Analysis ................................................................................ 281 10.4.3 Joint-Specic Models ............................................................................................. 282 10.4.4 Multisegment Foot Models ...................................................................................284 10.4.5 Sequential Modeling .............................................................................................284 10.4.6 Tracking Foot Bone Motion .................................................................................. 286 10.4.7 Descriptions of Joint Motion Using Biplane Fluoroscopy ................................ 286 10.4.8 Computational Modeling of the Foot.................................................................. 287 10.4.9 Cadaveric Gait Simulation ....................................................................................288
10.5 Summary and Future Perspectives ................................................................................. 289 Acknowledgments ...................................................................................................................... 290 References ..................................................................................................................................... 290
each lower extremity are three major joints, namely, the hip, knee, and ankle, as well as numerous smaller joints, most of which are in the foot. In this chapter, we review the lower extremities by rst summarizing the relevant anatomy, then describing the structure and function of the lower limb, and then providing more details of locomotion biomechanics.
