L4 Part 1: Functional Foot Orthoses (FFOs) Flashcards
Objectives: Make sure you know them ALL!!!
aka Exam Items***
1. Define functional foot orthosis (FFO)
- Define goals and mechanisms of FFOs based on Root’s theories
- Describe 5 criteria for abnormal pronation
- Understand how orthotic rx relates to presence, or absence, of compensatory motion
- Describe the basics of foot orthotic rx, including materials, length, supplemental materials, and wear schedule
- Compare and contrast custom and prefab’d foot orthoses
- Rx in-shoe orthoses for common foot pathos, such as Rearfoot Varus and Forefoot Varus
**SEE CASES IN CANVAS-THERE’S 2!!!!!!!
Functional Foot Orthosis (FFO)
Defined:
*Know underlined stuff!!!!
- Orthopedic device designed to promote structural integrity** of joints of the foot and lower limb by **resisting the GRFs** that cause **abnormal skeletal motion** during the **stance phase of gait
- Theory→ control motion==> DEC pain
A functional foot orthosis is an ortho device designed to __________ of the joints of the foot and lower limb by _________ that cause _________ during the _____ phase of gait
- Promote structural integrity
- Resisting the GRFs
- Abnormal skeletal motion
- Stance
Primary Goal of FFO:
*know _underlined stuf_f!!!
CONTROL abnormal foot functioning during stance
Mechanisms of a FFO: How does it work to control abnormal foot function?
3 things it DOES DO:
- Controlling excessive STJ and MTJ motion
- DEcelerating pronation
- *think post-tib
- Allowing STJ to function closer to its neutral position @ MSt
Mechanisms of an FFO:
3 things it DOES NOT DO:
- Do NOT support the MLA
- Do NOT provide cushioning and shock absorb.
- Do NOT adhere to the outside of a shoe
Conceptual Framework of a FFO
STN position→ according to Root:
- Pt of maximal congruence in articulation of talus and navicular
- Minimizes stress to surrounding tissues
- @ IC→ most eff. pos. for mm function and attenuation of impact forces
- Point where foot converts FROM mobile adapter TO a rigid lever
- *just BEFORE TSt when STJ is neutral and MTJ is fully locked
Conceptual framework of FFO is based on ___________
Normal alignment
“Normal” Alignment
According to Root
In loaded STN position
what does this look like/entail?
- Bisected lower leg is parallel w/ bisected calcaneus
- Plane of metatarsal heads perpendicular to bisected calcaneus
- Distal ⅓ of lower leg perpendicular to floor
Real-life challenges to operating under assumption that STN Pos=”Normal” alignment?
Pronation is important for adapting to surfaces, so diff to maintain “normal” STN pos.
What is “Normal” Pronation values?
4-6 degs
5 Criteria for Abnormal Pronation:
IMPORTANT!!!!!
- STJ pronation > normal 4-6degs
- Foot pronates @ wrong time→ disrupts normal seq. of events during CKC motion
- Pronation is recurrent, w/ ea step contributing to repetitive microtrauma to MSK structures
- *post-tib tendonitis
- Pronation happens @ loc. other than STJ
- Unnecessary destructive compensatory motion occurs in other planes of motion of STJ
Summary of FFO Basics
Purpose of FFO?
- Restore normal foot alignment and promote STN pos.
Summary of FFO Basics
In order to decide if pt needs FFO:
Examine foot-ankle alignment and STN position, as well as dynamic gait analysis
REVIEW LEG-HEEL ALIGNMENT TESTING AND STN!!!!!