Hallux Valgus and Custom Orthotic Prescription
Condition: Hallux Valgus
MeSH terms: Hallux Valgus; Bunion
Study type: Interventional

Summary: 
      Hallux valgus can be defined as a progressive subluxation of the first metatarsophalangeal
      joint and lateral deviation of the hallux. This common foot condition is associated with
      altered gait patterns. Specifically reduced forward propulsion, leading to gait instability.
      Research has shown that foot problems and pain play a major role towards the contribution of
      falls in the adult population. There are currently two main interventions for the treatment
      of hallux valgus: surgery and orthotic prescription. There has not been a lot of research
      performed evaluating the effects of custom orthotic prescription on hallux valgus.

      Therefore, this study will investigate adults with moderate hallux valgus and the effects of
      orthotic intervention on the efficacy of forward propulsion during walking. It is
      hypothesized that implementation of an orthotic will lead to decreased foot pain, an increase
      in step length, an increase in the forward moment about the ankle and hallux, and a more
      medial center of pressure tracking through the great toe instead of the lesser metatarsals.

      This study will consist of 10 adults. The participant will go through three rounds of testing
      in the lab. The first session will consist of initial baseline testing in which each
      participant will be evaluated for severity of Hallux Valgus and range of motion of the first
      metatarsophalangeal joint. A foot casting will then be performed by a pedorthist and the
      participant will be set up with markers, so as to record motion while they perform 15 walking
      trials across a 10m runway with a force plate embedded in the middle whilst wearing standard
      footwear (no orthotic). The second lab session will consist of the standard footwear (no
      orthotic) walking as well as the addition of standard footwear with custom orthotic walking.
      The third session, after having worn the orthotic for two weeks, will repeat both conditions
      measured in the second lab session. Data about the center of pressure trajectories, step
      length, foot pain, and the moments about the ankle and first metatarsophalangeal joints will
      be collected and calculated.
    

Detailed description: 
      The participants will enter the lab three times. On their first session, the level of
      severity of hallux valgus of the participant will be identified. The participant will sit in
      a chair, with their bare feet resting on the ground. A picture of their foot will be taken in
      the transverse plane. Another picture will then be taken of the foot when the individual is
      in a standing position. The participant will not experience any pain or discomfort during
      this test as only 2 pictures will be taken of the foot.

      The participant will then have range of motion testing performed on their first
      metatarsophalangeal joint. This will be performed by the researcher passively dorsiflexing
      the first metatarsophalangeal joint and measuring the angle created with a goniometer.

      The participant will also have an orthotic foot casting performed by a pedorthist. This foot
      casting will be performed to create a mould of the foot that will be used by a pedorthist to
      construct the orthotic.

      After the participant put on the standard footwear (no orthotic) they will be set up with
      optotrak markers with three on the first ray, three on the midfoot, three on the heel, and
      three on the medial distal tibia. Then the participant will walk across a 10m walkway with a
      force plate embedded half way along the walkway at a constant velocity for a total of 15
      trials. The participant will rate their pain on the visual analogue scale (VAS) immediately
      following the completion of the 15 walking trials.

      On the second session, the participant will once again be set up with optotrak marker and
      will perform 15 walking trials with the standard footwear (no orthotics) and rate their pain
      level on the VAS. The custom orthotic will be placed in the standard footwear. Then the
      participant will perform 15 walking trials and rate their pain on the VAS. The participant
      will then be instructed to wear the orthotic for seven hours a day, seven days a week for two
      weeks. During this two week period, the principal investigator will call the participant
      once, after about 1 week, to ask about how the orthotic wear is going. In specific, how often
      they have been wearing it and for how long.

      Two weeks later, the participant will return for their final testing session. This session
      will consist of a repetition of the 15 walking trials and vas ratings with both the standard
      footwear (no orthotic) and the standard footwear with the custom orthotic. The participant
      will then be debriefed and offered the opportunity to opt to have a summary of the results
      when the study is completed sent to them. They will be allowed to keep the custom orthotic.
    

Intervention name(s): Custom Made Orthotic
Intervention type(s): Device
Intervention description(s): Provides longitudinal arch support
Intervention model: Single Group Assignment
Masking: None (Open Label)
Primary purpose: Basic Science
Keywords: gait; orthotics; kinetics; hallux valgus; bunions