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

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.