Correlation between ultrasound assessment of musculature with lung function in patients with Duchenne muscular dystrophy

*Correspondence: [e-mail].

Abstract

Background: Duchenne muscular Dystrophy (DMD) is a genetic disease of recessive inheritance linked to the X chromosome, caused by a mutation in the dystrophin gene. This mutation will result in the dystrophin protein's absence, leading to musculoskeletal degeneration. The disease is the most common childhood-onset form of muscular dystrophy and affects males almost exclusively. DMD symptoms onset occurs in early childhood, usually between the ages of 3 and 5 years, with progressive muscle weakness and loss of gait in adolescence, progressive cardiomyopathy, and respiratory failure, leading to death. Spirometric parameters such as forced vital capacity (FVC) are used to monitor lung function. Muscle ultrasound has been increasingly used in neuromuscular diseases and allows you to evaluate the muscles individually.

Objective: To evaluate the correlation between lung function and muscle involvement in DMD at different stages of the disease.

Methods: This is a prospective observational study with 22 patients with DMD followed-up at the Hospital das Clínicas de São Paulo - HC/FMUSP, with the assessment of eleven muscles (axial, appendicular, and respiratory) by ultrasonography in Duchenne muscular dystrophy (DMD) patients through quantitative analysis by histogram and correlating the results with the Forced Vital Capacity (FVC).

Results: The muscle involvement of the 1st interosseous and rectus femoris increased proportionally with age. The degree of muscle involvement of the first interosseous, biceps brachii, deltoid, rectus femoris, anterior tibialis, and medial gastrocnemius muscles increased with the reduction of FVC with statistical significance. The correlation between the histogram of diaphragmatic and intercostal muscles with FVC was not statistically significant.

Conclusion: The 1st interosseous and Rectus femoris muscles had a statistical correlation with age and FVC. The degree of involvement of the diaphragm and intercostal muscles did not correlate with FVC, 1st interosseous bone may be an indirect marker of disease progression and respiratory involvement. The follow-up of these patients will determine the value of ultrasound in the long-term follow-up of respiratory and appendicular muscles in patients with DMD.

Publication History

Article published online:
12 May 2025