Footwear and Injury Prevention Study
Condition: Pronation Control
Study type: Interventional
Phase: Phase 3

Summary: 
      The purpose of this study is to assess whether shoes that are more controlling for movement
      of the foot and ankle, compared to shoes that are less controlling, will reduce the overall
      number and severity of injuries experienced during a 13-week running programme. Our
      hypothesis is that runners who wear more controlling footwear during the 13-week programme
      will experience less injury events.
    

Detailed description: 
      The proposed study will be a non-blinded prospective randomized cohort design.

      Subjects will include adult runners of both genders with no history of injury in the 6 months
      prior to study enrollment. Eligible participants will have no history of surgery or trauma to
      the lower extremity that might compromise their walking or running gait, and all subjects
      must be able to comfortably fit into their selected footwear.

      Three different foot posture sub-group classifications will be recruited: neutral, mild to
      moderate, and excessive. The subjects' foot posture will be classified using the Foot Posture
      Index (Redmond et al. (2006)(1). Twenty four subjects are estimated to be required within
      each foot posture sub-group; therefore 72 subjects will be our goal for enrollment. Subjects
      within each foot posture sub-group will be randomized into one of two separate footwear
      conditions: both the neutral group and the mild to moderate pronator group will be divided to
      receive either a neutral cushioned running shoe (a.k.a. 'neutral shoe'), or a shoe with mild
      stability components for controlling overpronation (a.k.a. 'stability shoe'); participants in
      the excessive pronator sub-group will be randomized to receive either a 'stability shoe' or a
      shoe will aggressive motion controlling features (a.k.a. 'motion control shoe').

      All subjects will undergo an initial baseline test, including an entrance interview for
      participant eligibility, training history, running injury history and documentation of lower
      extremity anthropometry (i.e. arch height, knee alignment, standing rearfoot position).
      Subjects will be randomized during their baseline test to their shoe condition and receive
      their shoes, training diary and running programme at that time.

      Once all subjects have completed their baseline testing, the official running clinic start
      date will commence on the following Saturday. A running clinic is established so that all
      subjects will have a chance to meet together, along with knowledgeable run leaders and a
      study co-investigator (MR), in order to increase group cohesion and provide an opportunity
      for data monitoring, programme feedback and subject questions. All subjects will begin the
      running programme at the official running clinic start date. The programme is designed to
      prepare individuals for a half-marathon (21 kilometre) running event in 13 weeks. Subjects
      will run on their own time, as indicating in their running programme, for the rest of the
      week until meeting again the following Saturday. This schedule will be repeated for the
      entire 13 week duration of the programme.

      Outcome variables of interest in this study include: 1) number of injury events, defined as a
      missed run workout that is associated with running related pain; 2) McGill Pain Questionnaire
      score(2) ; and 3) Visual Analog Scale (VAS) items for pain at rest, activities of daily
      living, during or immediately after running, respectively(3) . Outcome variables will be
      assessed at baseline, at the 6 week point in the running programme, and at the conclusion to
      the running programme.

      All data will be entered into a spreadsheet and statistical analysis software package JMP
      Version 4.0.0 (SAS Institute Inc., Cary, NC). In calculating statistical power for subject
      recruitment, a 20% difference in the VAS pain scores across groups will be considered to be a
      clinically meaningful difference. Accordingly, assuming a standard deviation of 2.3 in the
      VAS scores, an alpha of 5% and a beta error-level of 10%, twenty four subjects will be
      required within each foot posture sub-group; therefore 69 subjects will be our goal for
      enrollment. Each foot posture sub-group will undergo its own analysis procedure. Levene's
      test of equality of variance will precede a factorial analysis of variance in determining
      whether there are significant main effects for time and footwear condition, as well as an
      interaction effect, for all three dependent (or outcome) variables. Alpha will be set at 0.05
      for this study.

        1. Redmond AC, Crosbie J, Ouvrier RA. Development and validation of a novel rating system
           for scoring standing foot posture: The Foot Posture Index. Clin Biomech 2006;21:89-98.

        2. Melzack R. The McGill Pain Questionnaire: Major properties and scoring methods. Pain.
           1975; 1: 277-299.

        3. Wewers M.E. & Lowe N.K. A critical review of visual analogue scales in the measurement
           of clinical phenomena. Research in Nursing and Health 1990;13: 227-236.
    

Intervention name(s): Motion Controlling Running Shoe; Neutral Running Shoe
Intervention type(s): Device; Device
Intervention description(s): Running shoe with thermoplastic mid-foot shank stiffener, denser durometer foam on medial aspect of mid-sole, reinforced heel counter, wider sole-plate, and lateral foam crash-pad.; Standard running shoe with single density mid-sole foam.
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Treatment
Keywords: running; injury; pronation; footwear.