Bicycle Training on Ventilatory Functions in Duchenne Muscular Dystrophy

Ventilatory Functions Response to Bicycle Ergometry Training in Boys With Duchenne Muscular Dystrophy

The purpose of the study is to investigate the effect of bicycle ergometry training on ventilatory functions in boys with Duchenne muscular dystrophy.

Duchenne muscular dystrophy (DMD) is a common genetic X chromosome-linked recessive muscular dystrophy. It causes deterioration in mobility, progressive deformities in musculoskeletal system, upper limb impairment, and impaired airway clearance. Deterioration in respiratory muscles is the major cause of mortality and morbidity in DMD in their second to the third decade as a secondary complication in respiratory and cardiovascular systems. Cycling exercise is an easy functional treatment that considered as an aerobic exercise used to improve ventilatory functions, strength of respiratory muscles and therefore prevents respiratory diseases. Several studies support the benefit of bicycle ergometry training on ventilatory functions in different diseases while, there is no research conducted its effect on Duchenne muscular dystrophy. Hence, there is need to study the effect of bicycle ergometry training on ventilatory functions in Duchenne muscular dystrophy. Thirty boys with Duchenne muscular dystrophy aged from 8-10 years will be recruited from Abu El-Rish Pediatric Hospital. They will be divided randomly into control group (15 boys) and study group (15 boys). Control group will be participated in designed physical therapy program. Study group will be trained on the bicycle ergometer in addition to the same designed physical therapy program participated in control group.

Boys with Duchenne muscular dystrophy will receive the designed physical therapy program for 1 hour/ session.

Boys with Duchenne muscular dystrophy will receive the designed physical therapy program for 1 hour/ session in addition to bicycle ergometry training for 20 min./ session

The designed physical therapy program include gentle stretching exercises for biceps brachii, hamstrings and calf muscles bilaterally (5 times for every muscle) and isometric muscle contraction for quadriceps, hamstrings, anterior tibial group, calf muscles, biceps and triceps muscles (5 times for every muscle). Also, diaphragmatic breathing exercises will be applied.

The designed physical therapy program include gentle stretching exercises for biceps brachii, hamstrings and calf muscles bilaterally (5 times for every muscle) and isometric muscle contraction for quadriceps, hamstrings, anterior tibial group, calf muscles, biceps and triceps muscles (5 times for every muscle). Also, diaphragmatic breathing exercises will be applied + bicycle ergometry training

Spirometry will be used to measure forced vital capacity (FVC). It is the maximum volume of gas that can be expired when the child exhales as forcefully and as rapidly as possible after a maximal inspiration to assess the overall ability to move air in and out of the lungs. It is expressed in liter/minute.

Spirometry will be used to measure forced expiratory volume in the first second (FEV1). It is the volume of gas expired over a given time interval (the first second) from the beginning of the FVC maneuver that reflects airflow in the large airways. It is expressed in liter/minute.

Spirometry will be used to measure forced expiratory volume in the first second/forced vital capacity ratio (FEV1/FVC%). It is the relationship between forced expiratory volume in the first second (FEV1) and forced vital capacity (FVC) to determine if the respiratory pattern is obstructive, restrictive or normal pattern. It is expressed in (%).

The North Star Ambulatory Assessment (NSAA) will be used to to evaluate the ambulatory status of each boy. It is a 17-item scale (Standing-Walk-Stand up from chair-Stand on one leg Right & Left-Climb box step Right & Left-Descend box step Right & Left-Lifts head from supine-Gets to sitting-Rise from floor-Stands on heels-Jump-Hop Right & Left leg-Run 10-meters) that grades performance of various functional skills on a scale from 0 (unable), 1 (completes independently but with modifications), and 2 (completed without compensation).

Inclusion Criteria: Boys ages will be ranged from 8 to 10 years old. Confirmed diagnosis as Duchenne muscular dystrophy. Lower limb functional levels ranged from Grades 1 through 3 acc. to Vignos scale for lower extremities. Still ambulant and able to sit independently for at least 1 hour. Exclusion Criteria: Ccongenital or acquired skeletal deformities or cardiopulmonary dysfunction. Previous orthopaedic surgery in lower limbs. Behavioral problems causing inability to cooperate during the study.