Duchennes Muscular Dystrophy

Question 1

Description

Answer 1

Recessive X-linked form of muscular dystrophy which results in muscle degeneration and eventual deathCaused by the absence or severe abnormality of protein dystrophin

Question 2

Incidence

Answer 2

1/5000 live MALE births1/3 due to spontaneous mutation

Question 3

Presentation / Progression

Answer 3

Becomes clinically apparent about age 3-5Clumsiness, poor walking, frequent fallsMUSCLE WEAKNESS symmetricIn Pelvic girdle, then Shoulder girdleFinally respiratory and distal limb musclesMuscle contracturesDeath usually occurs from ventilatory failure, about age 20

Question 4

Associated Disorders

Answer 4

Restrictive pulmonary disease - restrict lung expansionCardiac abnormalitiesScoliosisLearning difficulties, 25% have IQ < 75Malignant hyperthermia - inability to regulate body temperature

Question 5

Clinical Signs

Answer 5

Calf Pseudohypertrophy - initially enlarged muscles eventually replaced by fat and connective tissueProximal muscle AtrophyGower’s sign- uses hands and arms to “walk up” on own body from squatted position, indicative of proximal weakness, especially of the lower limbsWide-based gaitAbnormal muscle biopsy/ genetic testing

Question 6

Cure?

Answer 6

Currently no cure

Question 7

Treatments

Answer 7

Prednisone- steroid that slow down rate of muscle deteriorationVentilation: non invasive, invasivePulmonary careROM, exercise, avoid overwork

Question 8

Progressive

Answer 8

Walking usually stops by age 12-13

Question 9

Contractures

Answer 9

Severe problemAnkle, hip, knee, IT band, elbow, wristAssociation between contractures and loss of ambulationAFOs and stretching prolong walking

Question 10

Tendon Releases

Answer 10

Bach and McKeon showed tendon releases with short term intensive rehab could Prolong ambulationReduce fallsImprove contracturesRelease of illiotibial band and tensor fascia lataeGluteus MaximusHamstringsAchilles tendon

Question 11

Scoliosis

Answer 11

Problems with skin breakdownpaindecreased sittinglimitations on cardiopulmonary reserveWithout intervention could progress to a mean of about 90 degreesBracing is not effective fore prevention of scoliosis or its progressionSurgical fusion when curve >35 degrees

Question 12

Other problems

Answer 12

OsteoporosisObesityHand dysfunction

Question 13

Hand Dysfunction

Answer 13

Difficulty with fine motor tasksPicking up heavy objectsFunctional deterioration begins about age 10Extrinsic and Intrinsic digital muscle shortnessSwan-neck and boutonniere deformitiesHyperextension of the interphalangeal jointsWrist flexion and ulnar deviation contractures

Question 14

Orthotic goal

Answer 14

Maintain ROM of wrist and handsBalanced forearm orthosis (BFOs) attached to wheelchairRobotic arm for ADLs