Biomecánica del pie

TUTORIAL

Diagnosis and Management of the Painful Ankle/Foot Part 1: Clinical Anatomy and Pathomechanics
Phillip S. Sizer Jr., PhD, PT1; Valerie Phelps, PT2; Roger James, PhD3; Omer Matthijs, PT4
1

Texas Tech University Health Science Center, Lubbock TX; 2International Academy of Orthopedic Medicine-US, Tucson AZ; 3Texas Tech University, Lubbock, Texas; 4 International Academy ofOrthopedic Medicine-Europe, Schoten, Belgium

Abstract: Distinctive anatomical features can be witnessed in the ankle/foot complex, affording specific pathological conditions. Disorders of the ankle/foot complex are multifactoral and features in both the clinical anatomy and biomechanics contribute to the development of ankle/foot pain. The superior tibiofibular, distal tibiofibular, talocrural, subtalar,and midtarsal joint systems must all participate in function of the ankle/foot complex, as each biomechanically contributes to functional movements and clinical disorders witnessed in the lower extremity. A clinician’s ability to effectively evaluate, diagnose, and treat the distal lower extremity is largely reliant upon a foundational understanding of the clinical anatomy and biomechanics of thiscomplex complex. Thus, clinicians are encouraged to consider these distinctions when examining and diagnosing disorders of the ankle/foot.
Key Words: Ankle, Biomechanics, Pathoanatomy, Subtalar, Talocrural Foot, Midtarsal,

INTRODUCTION
Painful disorders of the ankle foot complex present many challenges to clinicians. Complexities in structure and function can create difficulties in diagnosisand management. The distal location, while sharing many structural similarities with the wrist and hand, creates complicated behavioral distinctions when the lower extremity is functioning in the closed chain (with the foot planted on the ground). Likened to the wrist/hand, symptom localization is trustworthy, due to relatively small sensory receptive fields and reduced corresponding convergence ofthe afferent signals in the dorsal horn of the spinal cord. Like the proximal row of the carpals, the talus acts as an intercalated segment between the rigid mortise and semi-rigid tarsals.1 However, unlike the wrist/hand, the ankle/foot is required to frequently function in the close chain. As a consequence, the talus moves in reaction to the positions and movements of the surroundingarchitecture while the lower extremity bears weight.2 This behavior accounts for the multiple instantaneous axis orientations demonstrated by the talus with movements,3 whereby as these axes change, talar movement can be initiated by different forces and actions.

Send all correspondence and reprint requests to: Phillip S. Sizer Jr, PhD, PT, Texas Tech University Health Science Center, School of AlliedHealth, Doctorate of Science Program in Physical Therapy, 3601 4th St., Lubbock, TX 79430. Tel: (806) 743-3902.

© 2003 World Institute of Pain, 1530-7085/03/$15.00 Pain Practice, Volume 3, Issue 3, 2003 238–262

Diagnosis and Management of the Painful Ankle/Foot Part 1 • 239

There are five different mechanisms involved in ankle foot function, including the superior tibiofibular joint, thetalocrural coupling mechanism, the tarsal mechanism intercalated between the lower leg and the distal half of the foot, the tarsometatarsal mechanism, and finally, the metatarsophalangeal mechanism.4 Each of these contributes to the overall composite function of the entire lower extremity during any weightbearing behavior.2 Conversely, limits within any component can adversely influence the overallfunction of this entire system, resulting in compensatory behaviors in adjacent structures and potential tissue failure.

THE LOWER LEG
The superior tibiofibular joint (STFJ) anatomically belongs to the knee but functionally belongs to the ankle/foot. The STFJ is comprised of an oval synovial joint compartment located between the fibular head and proximal posterolateral tibia just distal to the...