Physical Medicine Interventions for Duchenne Muscular Dystrophy, the Including Avoiding Invasive Airway Tubes

7 II. STAGE 1: AMBULATORY INTERVENTIONS TO OPTIMIZE HABILITATION A. Prevention of Joint Contractures The physical/orthopedic treatment goals for DMD are to maintain the balance of strength across all major lower extremity joints, to prevent or reverse contractures, prolong the ability to walk safely without braces, and maximize arm function. Untreated, there is a strength imbalance in all major muscle groups of the lower extremities. When this imbalance is severe, tightening of the skin, muscles, tendons, and ligaments causes joint contractures that prematurely impair the ability to walk. B. Lower Extremities Stretching Loss of the ability to walk results from muscle weakness and from joint contractures that decrease range-of-motion (ROM) across weight bearing joints. Contracture severity is slowed, but not reversed, by performing aggressive ROM and joint stretching. ROM is performed to the point of maximal stretch, or a few degrees past the point of comfort, for several minutes a few times per day on joints with or prone to contractures. The most important leg muscle groups to stretch are the ankle plantarflexors, the hamstrings at the knees, and the hip flexors. Occupa- tional and physical therapists provide education and guidance for individualized home therapy programs. There is indirect evidence that regular stretching has prolonged the ability to walk for children with DMD to about 10 years by comparison to 6 or 7 years for children in the 1950s before such an emphasis. 1 No amount of stretching will prevent contractures when muscle strength imbalance is severe. C. Late Surgery Once contractures decrease limb function, the only way to restore function is to surgically release the joint’s tightened soft tissues. The most commonly used surgical protocol was one described for an 11 year old with DMD in 1845 then re-described in 1959. 2 It includes the surgical release of tight flexor muscles at the hips, knees, and ankles (the Achilles tendon), and the release of the iliotibial bands at the knees when the patient has been falling. Following this late surgery, long leg bracing was used. In the 1970s, up to 40% of NMD clinics 3 in the U.S. used late surgical interventions without the tibialis posterior transfers to balance strength at the ankles as patients “were about to lose their independent