Duchenne Muscular Dystrophy Multidisciplinary Approach by nikeborome

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									Duchenne’s Muscular
A Multidisciplinary Approach

By: Brittany Annis, Student PT
     Ithaca College 2010
   Introduce background information on
    Duchenne’s Muscular Dystrophy
   Identify associated pathologies
   Identify and explain the benefits of the
    multidisciplinary team members
   Describe the goals and interventions of
    physical therapy for DMD
   Describe current evidence and
    recommendations for exercise and DMD
               Intro to DMD
   Most prevalent childhood muscular
    dystrophy, every 1 in 3000-6000 male births
   X-linked recessive disorder- gene deletion
   Deficiency of the muscle protein Dystrophin
   Progressive muscle weakness in skeletal,
    smooth, and cardiac muscle
   It has been observed that there is a greater
    number of Type II muscle fibers with
    degeneration compared to Type I.

   Provides mechanical
    reinforcement to the
    membrane of muscle
    fibers; protects muscle
    fibers from being
    damaged while
    stressed during muscle
         Lifespan of DMD

 Shortened lifespan due to progressive
  muscle weakness and complications-
  mean age is 19 without intervention,
  mid-to-late twenties with proper care.
 Now, studies and research are showing
  that if properly diagnosed, individuals
  with DMD can have possible lifespan
  into their forties
             Signs and Symptoms
   Early signs between
    ages 3 and 5, when
    most commonly
     Delayed walking
     Inability to run, jump,
      keep up with peers
     Difficulty climbing stairs
     Gower’s Sign
     Frequent falls
     Occasionally (30%)
      global developmental
      delay and delayed
Associated Pathologies:
             Progressive weakness of hip
              and shoulder girdle musculature
             Weakness in paraspinals make
              walking difficult
             Leads to:
               – Waddling gait
               – Lumbar lordosis
               – Forward thrusting of the
               – Scapular winging
               – Anteroposterior scoliotic
               – Joint contractures
               – Respiratory impairment
               – Weight gain
        Associated Pathologies:
          Joint Contractures
   Mainly found at hips,      Equinovarus:
    knees, ankles               – Ankle plantarflexion and
                                – Tight gastrocnemius
                                  mm/Achilles tendon
   Contractured Tensor
                                – Associated weakness of
    Fascia Latae:                 tibialis anterior and
    – Waddling gait               peroneal mms
    – Tightened IT Band        Complications include:
    – Resultant hip and            Difficulty wearing shoes
      knee                         Foot pain
      pain/deformities             Hypersensitivity
                                   Concern about foot’s
     Associated Pathologies:
 Most commonly seen when non-
  ambulatory, due to increased amount of
  time spend seated in a wheelchair
 May require spinal fusion to promote
  better sitting and comfort, to prevent
  further deformity, avoid respiratory
    The Multidisciplinary Team
 Can alter the natural     –   Rehabilitation
  progression of the        –   Orthopedics
  disease and improve
  function and quality of   –   Pharmocologics
  life.                     –   Psychosocial
 Comprehensive set of      –   Respiratory care
  recommendations to
  manage the wide           –   Cardiovascular care
  spectrum of               –   Pain
  complications             –   Gastroenterology/
 Includes:                     Nutrition
   Currently the best treatment option available
   Improve muscle strength and function
   Significantly slow the progression of muscle
   Prolong ambulation to mid-teens or later
   Delay the onset of respiratory and/or cardiac
   [Use caution: complications include weight
    gain, vertebral fractures, failure to gain
    height, irritability]
Respiratory Management
   Patients with DMD are at increased risk of respiratory
   Because of progressive loss of muscle strength:
     – Cough may be ineffective
     – Nocturnal hypoventilation
     – Sleep-disordered breathing
   PT can assist with respiratory management by having patient
    breathe against a resistive load (water in pool), breath-holding,
    bubble-blowing, to improve ventilatory strength and endurance.
   Important to note signs and symptoms of hypoventilation to refer
    patient to respiratory physician.
     – Fatigue, dyspnea, tachycardia, morning/continuous
        headaches, sleep dysfunction, nightmares, difficulty
Cardiac Management
 Cardiomyopathy and/or cardiac arrhythmia
  are major sources of mortality in DMD
 The heart/myocardium have areas of
  hypertrophy, atrophy, and fibrosis
 Failure to see a cardiac specialist early in the
  disease process have led to late treatment
  and poor outcomes
 Higher levels of fitness are associated with
  better cardiac health
            Potential Surgeries
 Heelcord lengthening
 Hamstring lengthening
 ITB lengthening
 Cannot perform hip flexor lengthening
  (responds poorly, weakens muscles and
  cannot properly brace)
    – Hip deformities often correct themselves once
      knee and ankle malalignments have been altered.
   Surgery in the late ambulatory phase or after
    is usually not effective.
Other Important Teams:

 Nutritional, swallowing, gastrointestinal,
  speech and language, pain
  management, psychosocial,
 All fields are continuously changing as
  the stages of the disease change
       Goals of Physical Therapy
   Prolong independent
   Maximize functional
   Prevent complications
    of inactivity
   Improve emotional well-
Physical Therapy Interventions

 Stretching/Positionin      Objective measures
  g                           and testing to
 Management of               monitor progression
 Assistive devices
 Exercise
               Objective Measures
   Strength testing- MMT to            ROM: goniometry to identify
    monitor disease progression          hypomobility, jt contractures
    and predict functional losses,       that may contribute to
    assess responses to                  functional deterioration or to
    treatment and monitor                ry complications, or to note
    muscle imbalances                    need of splinting/orthotics.
      – Test LEs every 6 months           – In ambulatory phase,
        when ambulatory; test                measure hips, knees,
        UE and LE every 6                    ankles (ITB, H/S,
        months when non-                     heelcords). In non-
        ambulatory                           ambulatory phase,
                                             measure UE as well as
                                             LE (elbows, wrists, finger
       Objective Measures, Con’t
   Timed Testing:                   ADLs: Assessment
    Standardized tests are            of impairment in
    responsive to change,
                                      home, school,
    easy to administer,
    relevant to function              community settings
    (when ambulatory only)            – Frequency of falls,
    – Timed 10 meter walk,              self-care skills
      timed Gower’s
      manuever, time to climb
      4 stairs, 6 min walk test
                              Heelcords: Gastrocnemius/
 Combination of               Achilles Tendon lengthening
  AROM, AAROM,                 into dorsiflexion
  PROM, prolonged             Tensor Fascia Latae/Iliotibial
                               Band: stretch hip into
  elongation (splinting,       adduction, internal rotation,
                               and extension.
                              Other muscles throughout
 Minimum of 4-6               the hips, knees and ankles
  days per week, at           In non-ambulatory phase,
                               also focus on upper
  home/school and in           extremities: finger flexors,
                               wrist flexors, elbow and
  the clinic                   shoulder joints
        Assistive Devices: AFOs

 Custom-molded and comfortable for optimum
  foot and ankle alignment
 Throughout life: AFO’s are appropriate at
  night to prevent or minimize the progression
  of equinus contractures
 Late stages:
    – KAFOs for non-ambulatory boys to prevent
      contracture and deformity (not for use at night)
    – Resting hand splints for finger flexors
         Assistive Devices Con’t
   Wheelchair: Need                 Standing Frames: A few
    appropriate postural              hours per day, even
    positioning to prevent            with minimal weight
    scoliosis and back                bearing, to prevent and
    pain/aches                        reduce the severity of
    – Powered for more                contractures, decubitis
      involved patients.              ulcers, and scoliosis.
    – Manual Lightweight for          Also improves bone
      less involved patients so
      can self propel and             mineral density,
      increase independence,          circulation, and GI and
      as well as provide arm          respiratory functions.
   There is a high level of controversy concerning
    whether exercise is beneficial or harmful to patients
    with DMD
   Normal, dystrophic muscle (those without muscular
    dystrophy) can withstand mechanical forces during
   Those with muscular dystrophy are compromised due
    to weakened muscles, joints, tendons, and bones
    during muscle contractions and weight-bearing.
   But exercise is very important to avoid disuse atrophy
    and other secondary complications of inactivity
          Type I vs Type II Fibers
   Type I muscle fibers are            It is possible to switch Type
    slow twitch for slower               II muscle fibers to Type I with
    contractions, and fatigue-           exercise training, so with an
    resistant, so good for               increased number of Type I
    continuous contractions              fibers, the muscles are more
    (postural muscles)                   durable and more resistant
   Type II muscle fibers are fast       to degeneration.
    twitch for quick contractions,      But the form of exercise
    and are easily fatigued              needed to switch Type II
    (“sprinter” muscles). They           fibers to Type I is very
    are also less resistant to           specific
    mechanical stresses (more
    easily injured)
     Current Evidence Regarding
   In a mouse study, a          It has been observed
    greater percentage of         that Type II muscle
    Type I muscle fibers          fibers are subject to
    were observed after low       greater degeneration,
    intensity, long-term          and the majority of
    exercise                      research using animal
   Sedentary mice with           models and some
    DMD had a higher              human studies suggest
    percentage of Type I          that increasing activity
    fibers than sedentary         may actually slow the
    mice without DMD              degeneration in
                                  dystrophic muscle.
       Current Evidence, Con’t

   Further studies and information are
    needed for each subtype of muscular
    dystrophy to create subtype-specific
    recommendations, including specifics
    such as age, severity, rate of
    progression, and level of motivation.
         Recommended Exercise
              for DMD
   Low resistive and                  Long term, low-
    aerobic exercise are                intensity, preferably no
    justified to:                       load (or low-load)
    – Prevent deconditioning,
      decreased fitness, disuse
                                        weight-bearing activity
      atrophy and joint                 to reduce mechanical
      contractures                      stress on the muscle
    – Counteract secondary              – Increased Type I fibers,
      complications of inactivity         which are less vulnerable
      such as obesity,
                                          to degeneration
      Diabetes, osteoporosis
      and cardiovascular                – Will not promote
      diseases                            hypertrophy
         Recommended Exercise
            for DMD, Con’t
   Use caution to ensure       Aquatic Therapy!
    that cardiovascular or       Excellent for improving/
    muscular complications       maintaining mobility,
    do not develop               strength, flexibility, and
   High-resistance and          aerobic conditioning
    eccentric exercise is        and cardiopulmonary
    NOT recommended,
    although it has not          fitness
    actually been proven
    harmful for a DMD
                  Current Evidence
   Research and studies are being done with continuous
    advances and milestones in DMD research

   The severity of DMD can be determined by a positive
    correlation to the amount of dystrophin present in the
    muscle (the more dystrophin, the less severe the
    symptoms and progression)

   Corticosteroid prednisone was found effective in slowing
    the progression of DMD, and it also stimulates utrophin
    production ( a mm protein similar to dystrophin)

   Gene therapy clinical trials are underway and dystrophin
    gene injections are judged safe in clinical trial including 6
    boys with DMD; studies are being continued
                                Works Cited
Ansved, Tor. "Muscular Dystrophies: Influence of Physical Conditioning on Disease
    Evolution." Current Opinion in Clinical Nutrition and Metabolic Care 6 (2003): 435-39. Print.
Bushby, Katharine, Richard Finkel, and David Birnkrant. "Diagnosis and Management of
    Duchenne Muscular Dystrophy, Part 1: diagnosis, and pharmacological and psychosocial
    management." 30 Nov. 2009. Web. 1 Dec. 2009. <http://quest.mda.org/files/pdfs/Part_1-
Bushby, Katharine, Richard Finkel, and David Birnkrant. "Diagnosis and Management of
    Duchenne Muscular Dystrophy, Part 2: implementation of multidisciplinary care." 30 Nov.
    2009. Web. 1 Dec. 2009. <http://http://quest.mda.org/files/pdfs/Part_2-newDMD.pdf>.
Ciafaloni, MD, Emma, and Richard T. Moxley, MD. "Treatment Options for Duchenne Muscular
    Dystrophy." Current Treatment Options in Neurology 10.2 (2008): 86-93. Print.
Milestones in Duchenne's Muscular Dystrophy Research. MDA.org, Feb. 2009. Web. 1 Dec.
    2009. <http://www.mda.org/publications/milestones/dmd.html>.
Palmieri, B., V. Sblendorio, A. Ferrari, and A. Pietrobelli. "Duchenne Muscle Activity Evaluation
    and Muscle Function Preservation." Obesity Reviews 9 (2008): 121-39. Print.
Sayers, Stephen P. "The Role of Exercise as a Therapy for Children with Duchenne Muscular
    Dystrophy." Pediatric Exercise Science 12 (2000): 23-33. Print.

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