Muscle Activation in Chronic Ankle Instability and the Effect of an Exercise Programme
Condition: Ankle Injuries
MeSH terms: Ankle Injuries
Study type: Interventional

Summary: 
      This study aims to investigate the activity patterns of the peroneal muscle group, in
      individuals with a history of chronic ankle instability (CAI) of the ankle injuries compared
      with individuals without ankle problems. The study also aims to determine the effect of a
      targeted exercise programme on this muscle group in patients with CAI.

      Research on this topic may provide important insight on the roles of these muscles in chronic
      ankle instability and investigate whether specific strengthening programmes are effective in
      this complex patient category.
    

Detailed description: 
      The purpose of this study is to evaluate the role of the peroneus brevis (PB) and peroneus
      longus (PL) muscles in patients with chronic ankle instability and to determine whether an
      eccentric- concentric focused training intervention has an effect on these muscles.

      Volunteers will be recruited from Orthopaedic Clinics and the Musculoskeletal Assessment
      Clinics in St. Vincent's University Hospital. Posters and information leaflets will be
      supplied to areas where volunteers are being sought. A study information sheet will be given
      to the patient and written consent will be obtained prior to commencing the investigative
      study.

      Inclusion Criteria The selection criteria for chronic ankle instability (CAI) patients will
      be based on the position statement of the International Ankle Consortium (Gribble et al.
      2013).

        -  A history of at least 1 significant ankle sprain

        -  A history of the previously injured ankle joint "giving way", and/or recurrent sprain,
           and/or "feelings of instability". Self-reported ankle instability confirmed with
           validated ankle instability-specific questionnaire: The Cumberland Ankle Instability
           Tool (CAIT). CAIT is a simple, valid, and reliable tool to measure severity of
           functional ankle instability.

        -  A general self-reported foot and ankle function questionnaire is also completed. The
           Foot and Ankle Ability Measure (FAAM): The FAAM is a reliable, responsive, and valid
           measure of physical function for individuals with a broad range of musculoskeletal
           disorders of the lower leg, foot, and ankle.

      Exclusion Criteria

        -  Acute injury to musculoskeletal structures of other joints of the lower extremity in the
           previous 3 months that impacted joint integrity and function (ie, sprains, fractures),
           resulting in at least 1 interrupted day of desired physical activity

        -  Any Neurological problem that would affect muscle function of the lower limb

        -  Pregnant Women

        -  Participants under 18 and over 65 Controls

        -  Healthy Volunteers (Control) will be age and sex matched to their CAI variants

        -  Will have no previous history of significant ankle sprain, which interrupted desired
           physical activity.

      CAI patients will then be referred on for two radiological examinations in St. Vincent's

      Hospital to aid diagnosis:

        1. A diagnostic ultrasound will be performed by Dr. Eric Heffernan to look at peroneal
           tendon pathology and ligament character (thickening and continuity).

        2. Stress Fluoroscopy (Anterior Drawer and Talar Tilt) will be performed by Professor
           Robert Flavin to assess for biplanar instability and to out rule subtalar instability.

      Both participants with CAI and participants without ankle instability will undergo Surface
      electromyography (S-EMG) assessment of the PL, PB and Tibialis Anterior (TA) in both static
      and dynamic conditions in the University College Dublin School of Public Health,
      Physiotherapy & Population science (SPHPPS) motion analysis laboratory (This assessment
      process will initially be piloted on a healthy volunteer) Muscle onset will be determined and
      S-EMG will also normalized to Max Voluntary Contraction (MVC) determining the magnitude of
      activation, during Single leg Stance, wobble-board standing, walking, calf-raise exercise,
      tip-toe walking, jogging and a jump-landing task.

      Kinematic variables (degrees of movement and speed) will also be re-coded using CODA motion
      capture system during the movement tasks.

      The participants will be performing the functional tests on a force platform to allow for
      assessment of kinetic variables measuring ground reaction force and measures of postural
      control.

      Following S-EMG testing the CAI subjects will commence a six-week eccentric-concentric
      focused exercise programme.

      The exercise intervention will consist of an individual home-based progressive
      eccentric-concentric strengthening programme. Patients will be reviewed every two weeks
      during their rehabilitation; exercises will be progressed accordingly by their
      physiotherapist.

      Patients will be supplied with exercise diaries to assist with adherence to the exercise
      protocol.

      At the end of the six-week programme they will undergo repeat S-EMG testing and complete the
      self-reported ankle questionnaires used at pre-test phase.

      If using a power level of 80% and 5% significance, a sample size of 13 participants for each
      study group would be required for this study. To allow for a 23% dropout rate we will aim to
      recruit 16 patients to each group.
    

Intervention name(s): Exercise
Intervention type(s): Other
Intervention description(s): The exercise intervention will consist of an individual home-based progressive eccentric-concentric strengthening programme. Patients will be reviewed every two weeks during their rehabilitation; exercises will be progressed accordingly by their physiotherapist.
Intervention model: Single Group Assignment
Masking: None (Open Label)
Primary purpose: Treatment