A Novel Method to Detect the Thickness of Adductor Pollicis Muscle Using Ultrasound in Stable Chronic Obstructive Pulmonary Disease Patients

Abstract

Objective: The aim of this study was to design an ultrasonic method to measure the adductor pollicis muscle thickness (APMT) of stable chronic obstructive pulmonary disease (COPD) patients. We also tested handgrip strength (HGS) to study the relationship between APMT and HGS in COPD patients. Method: 40 Stage I ~ II COPD out-patients and 20 non-COPD controls participated in the study. The ultrasound measurements of APMT were made with the subjects sitting with his or her hand lying on the knee, and put the 10 MHz probe on the triangle formed by the extension of the thumb and index finger. The ultrasonic APMT measurements start at the tip of the dorsal interosseous muscle, obliquely to the contralateral adductor pollicis fascia, the measuring lines overlapping to the path between champing points of caliper. The average of 3 consecutive measurements was considered to be the muscle thickness. The kappa coefficient was applied to assess the degree of the inter- and intra-observer agreement. Results: Ultrasound can be used to measure the thickness of adductor pollicis muscle conveniently. The APMT of dominant hand of men were 9.78 ± 0.34 mm, and women were 7.37 ± 0.48 mm in our 40 Stage I ~ II COPD out-patients. There were significant differences in APMT and HGS by genders. The APMT had a significant positive correlation with HGS (r = 0.676; P < 0.0001) in our COPD patients. The inter- and intra-observer reliability of ultrasonic APMT measurement was satisfactory. Conclusion: Ultrasonic adductor pollicis muscle thickness measurement is a new way and with excellent inter- and intra-observer reliability; it can be used as a new clinical metrology of nutritional status research and upper limb muscle function evaluation. Funding Statement: This work was supported by grants from Shanghai Municipal Health Commission (No. 201740227) and Shanghai University of Medical & Health Sciences (No. E1-0200-18-201116). This work was also supported by the National Natural Science Foundation of China (No. 81701547) and the Beijing Medical and Health Foundation (No. YWJKJJHKYJJ-F2187E). Declaration of Interests: The authors report no conflicts of interest in this work. Ethics Approval Statement: The project was approved by the Ethics and Research Committee of our institution (number 2015ky134).