BookDouglas H. Richie, Jr.
Summary: This new book consolidates the current knowledge of lower extremity biomechanics and pathomechanics and makes this information relevant to the study of common foot and ankle pathologies. The content is presented in a language and format that allows the clinician to review current evidence explaining the etiology of these disorders in order to formulate effective treatment interventions. In order to understand pathomechanics, the clinician must also become versed in the normal, healthy biomechanics of the lower extremity. A review of gait, muscle function and forces acting on the lower extremities during physical activity will be the focus of the first part of this book. The second part of the book will study the common, challenging pathologies treated on a daily basis by foot and ankle clinicians: hallux abducto valgus, hallux rigidus, metatarsalgia, digital deformities, adult acquired flatfoot, and plantar heel pain. These chapters discuss all the relevant factors contributing to these conditions, evaluating and exposing myths and misconceptions about the pathomechanics and treatments of these conditions. For each disorder, a comprehensive review of published research provides a foundation for an updated, valid description of etiology and risk factors. Providing a fresh approach to lower extremity pathomechanics and management strategies, Pathomechanics of Common Foot Disorders is a valuable resource for podiatrists and orthopedic foot and ankle surgeons at all levels. .
Contents:
Intro
Preface
Pathomechanics
References
Acknowledgments
Contents
1: Comparative Anatomy and Introduction to the Twisted Plate Mechanism
The Specialization of the Human Foot
Ontogeny of the Human Foot
Does Ontogeny Recapitulate Phylogeny of the Human Foot?
Ankle and Hindfoot Development: Twisting the Plate of Bones
Ontogeny of the Forefoot
Rotation of Segments
The Twisted Plate Provides the Specialized Function of the Human Foot
Clinical Application of the Twisted Plate Mechanism
Twisting the Plate and Locking for Optimal Foot Function High-Gear Push Off
What Initiates High-Gear Push Off?
Testing the Theory of High-Gear Push Off
What Is the Ideal Alignment of the Human Foot?
The Myth of Midfoot "Locking"
What Stiffens the Human Foot?
The Springlike Function of the Human Foot
Summary
References
2: Human Walking: The Gait Cycle
Introduction
Kinetics
Key Events in the Walking Gait Cycle
Phase 1 Initial Contact 0- 2% of the Gait Cycle (Fig. 2.3)
Phase 2 Loading Response 2-12% of the Gait Cycle (Fig. 2.4)
Phase 3 Midstance 12- 31% of the Gait Cycle (Fig. 2.5) Phase 4 Terminal Stance 31-50% of the Gait Cycle (Fig. 2.6)
Phase 5 Pre-swing 50-62% of the Gait Cycle
Phase 6 Initial Swing 62-75% of the Gait Cycle Events (Fig. 2.8)
Phase 7 Mid-swing 75-87% of the Gait Cycle (Fig. 2.9)
Phase 8 Terminal Swing 87-100% of the Gait Cycle (Fig. 2.10)
Common Compensatory Changes Observed in Gait
References
3: Motion of the Foot: Joints, Muscles, and Sensorimotor Control
Introduction
General Motion of the Foot Segments
The Bone Pin Studies
The Lateral Metatarsals Move More than the Medial The Navicular-Cuneiform Joints Move More than the Midtarsal Joint
The Midfoot Joints Contribute More Sagittal Plane Motion than the Ankle
The Medial Column Moves More than the Ankle
Pure Ankle Joint Motion Can Now Be Measured
The Ankle Moves in the Transverse and Frontal Planes
There Is more Frontal Plane Motion in the Ankle than the Subtalar Joint
The Talonavicular Joint and the Calcaneocuboid Joints Move More than the Subtalar Joint
Majority of First Ray Motion Is as the Naviculocuneiform Joint
The Lateral Metatarsals Move More than the Medial Metatarsals The Lateral and Medial Columns Have the Same Sagittal Plane Motion
How Does the "Normal" Foot Function in Gait?
Neuromuscular Control
Do Joint Axes Determine Direction and Range of Motion?
Muscle Function in the Lower Extremity
Phasic Activity
Muscle Strength
Moment Arm
Major Muscle Contributors in Six Planes of Motion (Summary of Table 3.2)
Sagittal Plane
Frontal Plane
Transverse Plane
Muscle Activity/Demand and Foot Type
The Plantar Intrinsic Muscles
Storage and Return of Energy
Twisting the Plate Stores and Releases Energy
References