Weightbearing Assessment of Tarsal Instability

Study Overview
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Brief Summary
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The purpose of this study is to compare the average joint motion and joint axis orientation of the hindfoot bones between patients diagnosed with adult-acquired flatfoot disorder (AAFD) and a control group of patients without foot deformity, using weight-bearing CT technology.

Official Title
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In-Vivo Physiologic Weight-Bearing Assessment of Tarsal Instability: Three-Dimensional Cone-Beam Computed Tomography Analysis

Conditions
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Adult-acquired Flatfoot Disorder (AAFD)

Intervention / Treatment
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* Radiation: Weightbearing CT


Participation Criteria
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Eligibility Criteria
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Symptomatic group: Inclusion Criteria: 1. adult patients (ages 18 -80 years old) diagnosed with Stage 2 AAFD Exclusion Criteria: previous surgery infection tumor in the affected foot pregnancy Control group: Inclusion Criteria: 1. adult patients (ages 18 -80 years old) without foot deformity Exclusion Criteria: history of previous foot and ankle surgery foot deformity known foot and ankle pathology pregnancy

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Diagnostic
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Weightbearing CT (AAFD group)<br>Weightbearing CT scan of affected foot | Radiation: Weightbearing CT<br> <br> |
| Active Comparator: Weightbearing CT (control group)<br>Weightbearing CT scan of normal foot | Radiation: Weightbearing CT<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Joint Motion Between Touch-down Bearing Navicular and Full-weight Bearing Navicular | Relative motion, which is the position of the full weightbearing (FWB, greater that 75-100% body weight) navicular in comparison to the touch down weightbearing (TDWB, 25-50% body weight) navicular position, will be determined by comparing the joint orientation across these two points on one CT scan. The difference between the two positions is reported below. | 1 CT scan, one reading while touch-down bearing, one reading while full-weight bearing | 
| Change in Navicular Rotation Between Touch-down Bearing and Full-weight Bearing | Relative motion across joint segments will be determined by comparing the joint orientation across two time points: touch-down bearing (TDWB, 25-50% body weight) and full-weight bearing (FWB, greater that 75-100% body weight) as measured on CT. | 1 CT scan, one reading while touch-down bearing, one reading while full-weight bearing | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Adult-acquired flatfoot disorder (AAFD), flexible flatfoot, computed tomography (CT)