Clinimetric Properties of Muscle Mass and Stiffness Measurements of the Quadriceps in Patients With COPD

Clinimetric Properties Assessment of Quadriceps Muscle Mass and Stiffness Using Perimetry and ShearWave Elastography in Patients With COPD : a Prospective Observational Study

A large amount of patients with COPD suffer from muscle dysfunction characterized by losses of muscle mass and strength. Studies have shown an association between a loss of quadriceps muscle mass and premature death.

This study aims to investigate the clinimetric properties of a simple quadriceps perimetry and ShearWave elastography to improve the monitoring of skeletal muscle function in patients with COPD.

Muscle dysfunction in COPD is characterized by reduced skeletal muscle mass and strength, particularly in the lower limbs. These systemic consequences of COPD play a key role in the course of these patients, through their impact on functional status, quality of life and increased mortality. Early detection and monitoring of muscular status in these patients could help improve management and limit the consequences of the disease.

Numerous studies show that variation in quadriceps mass has a significant relationship with premature mortality in this disease. The use of an indirect but simple and affordable measure: perimetric tape-measurement of thigh circumference, could help monitor quadriceps muscle mass in these patients on a regular and cost-effective basis. However, the clinimetric properties (validity, reliability, response to treatment) of this measurement need to be assessed to clarify its relevance.

On the other hand, ShearWave ® elastography (SWE) is a new method of measuring quadriceps stiffness. This measurement could provide additional information on muscle quality compared with conventional measures of strength or muscle trophicity. The potential added value of SWE ® for COPD patients has not yet been investigated. This tool would provide more precise indications of the state of the quadriceps, with the aim of improving the management of this pathology.

Inclusion Criteria:

• COPD patients
• Adults (>18 years old)
• Patients starting a pulmonary rehabilitation (PR) programme

Exclusion Criteria:

• Patients included in other research protocol
• Minors or under guardianship
• Pregnancy
• Patients with lower limb amputation or history of neuromuscular disease
• Cardiovascular contradications for PR