Multisegmented Foot Motion in Patients With Lateral Ankle Sprains and Chronic Ankle Instability

Arm 1:The purpose of this arm of the study is to determine if foot muscle exercises change
the function of the foot. Up to 25 people will be enrolled in this arm of the study at the
University of Virginia.

Arm 2: The purpose of this arm of the study is to determine if joint mobilization applied to
the middle part of the foot will effect function in people who are healthy, have a history
of lateral ankle sprains (LAS), or have chronic ankle instability (CAI) and have joint
stiffness. Up to 125 people will be enrolled in this arm of the study at the University of
Virginia. CAI is a condition where symptoms from an ankle sprain last longer than one year.
These symptoms include a feeling of looseness, feelings that the participant may roll the
ankle, or repeated ankle sprains. This study may help clinicians prescribe simple exercises
at home to help treat CAI. The participants are being asked to be in this study, because
they are physically active (participate in some form of physical activity for at least 20
minutes per day, three days per week) and are not currently seeking medical
treatment/therapy for LAS/CAI. Joint mobilization is a commonly used clinical intervention
used to decrease pain and increase joint range of motion. The home exercises employed for
this study are commonly used clinically in the treatment of foot and ankle problems and
include a foot and calf stretch and standing on one foot for 60 seconds. The participant
will be asked to perform these exercises three times daily throughout the course of the day.

The investigators hypothesize that joint mobilization will improve patient oriented outcomes
and measures of joint mobility and excursion in individuals with impaired foot mobility
immediately post intervention and at 1-week follow-up, but not at 4 weeks; and intrinsic
foot strengthening will result in differences in morphologic measures and intrinsic muscle
cross-section in healthy individuals following a 4 week home exercise program.

Inclusion Criteria:

Healthy participants

- Aged 18-50

- All subjects will be physically active: Participating in some form of physical
activity for at least 20 min per day, three times per week.

- All subjects will have no history of ankle injury.

LAS participants

- Aged 18-50

- All subjects with a history of ankle sprains, no lingering symptoms or disability,
not actively receiving treatment for their ankle sprain

- All subjects will be physically active: Participating in some form of physical
activity for at least 20 min per day, three times per week.

CAI participants

- Aged 18-50

- CAI with a history of recurrent ankle sprains, with the first sprain occurring longer
than 12 months ago. They will have lingering symptoms, and disability, but not
actively receiving treatment for their CAI

- All subjects will be physically active: Participating in some form of physical
activity for at least 20 min per day, three times per week.

Exclusion Criteria:

- Neurological or vestibular disorders affecting balance

- Currently seeking medical care for LAS/CAI

- History of prior ankle surgery

- History of ankle or foot fracture

- Diabetes mellitus

- Current self-reported disability due to lower extremity pathology that may adversely
affect neuromuscular function

- Lumbosacral radiculopathy

- Soft tissue disorders including Marfan's syndrome and Ehlers-Dandros syndrome

- Absolute contraindications to manual therapy

- Pregnancy