Validation of an on-screen application-based measurement of shoulder range of motion over telehealth medium.

BACKGROUND: Shoulder range-of-motion (ROM) assessment is vital for the follow-up evaluation of operated patients and for the outcome-based research studies. The aim of this study was to investigate the accuracy and reliability of a remote on-screen application (app)-based method of shoulder ROM measurement through a telehealth medium. MATERIALS AND METHODS: A consultant shoulder surgeon, a board-certified orthopedic resident, and a graduate medical doctor served as the examiners. The cohort consisted of 24 healthy volunteers and 16 symptomatic patients with expected shoulder ROM deficits. Shoulder ROM was first examined physically using a goniometer in the clinic and then over Zoom remote conferencing using the protractor extension app of the Chrome browser. RESULTS: Instrument validity was examined by comparing the goniometer method with the protractor app-based method of the expert shoulder consultant using Bland-Altman analysis. It showed only minor mean differences between the healthy volunteers and the patients in elevation (2.0° and 5.0°, respectively), abduction (2.0° and 3.0°, respectively), external rotation with the elbow adducted (1.9° and 0.2°, respectively), external rotation with the elbow abducted at 90° (0.4° and 4°, respectively), and internal rotation with elbow abducted at 90° (2.3° and 1.2°, respectively), with limits of agreement that were below the well-established minimal clinically important difference values. The intraclass correlation coefficient (ICC) values varied between 0.83 and 0.96 for the volunteers and between 0.90 and 0.98 for the patients, indicating excellent correlation between the 2 methods. The interobserver reliability between 2 examiners for the protractor app-based method as evaluated by ICC scores was excellent; it ranged between 0.86 and 0.98 for the volunteers and between 0.88 and 0.99 for the patients. Comparison of the protractor app-based method with the gold-standard goniometer method for the resident and the graduate doctor showed excellent ICC values. CONCLUSION: A protractor app-based method of measuring shoulder ROM over a telehealth medium is accurate and reliable compared with a clinical goniometer method. This validated method can be used during remote telehealth consultation with significant benefits of saving patients travel and time during the COVID-19 (coronavirus disease 2019) pandemic and even later.

Geometric analysis of the humeral head and glenoid in the Indian population and its clinical significance.

BACKGROUND: Total anatomic and reverse shoulder prostheses are designed to match the dimensions of the native bony anatomy. Chinese and Japanese bony dimensions of the shoulder have been found to be different from that of the Caucasian population. We hypothesized that the geometric dimensions of the humeral head and glenoid in the Indian population would also be different from that of the Caucasian population. METHOD: Fifty patients underwent computerized tomographic scans of their normal shoulders. We calculated the superoinferior (SI) diameter of the humeral head, anteroposterior diameter of the humeral head, radius of curvature of the humeral head, humeral head retroversion, humeral head thickness, inclination angle, critical shoulder angle, greater tuberosity angle, glenoid width, glenoid length, radius of curvature of the glenoid, glenoid inclination angle, and glenoid version. RESULTS: The radius of curvature of the humeral head averaged 22.9 ± 1.7 mm, the articular surface thickness 17.1 ± 1.6 mm, and the SI diameter 42.3 ± 3 mm. The SI diameter strongly correlated with the thickness (r = 0.617, P = .001). The anteroposterior/SI articular surface diameter ratio averaged 0.9 ± 0.9, the articular surface thickness/radius of curvature ratio 0.7 ± 0.9, the inclination angle 133.8 ± 6.4, and the retroversion angle 33.5° ± 8.5°. The radius of curvature of the glenoid averaged 23.3 ± 3.4 mm, the glenoid width 24.0 ± 2 mm, the SI length 31.3 ± 2.2 mm, the glenoid inclination angle 78.7° ± 4.8°, and the glenoid retroversion 1.8° ± 3.8°. DISCUSSION: Compared with the Western population, our cohort had a smaller humeral radius of curvature (P = .04), smaller articular surface diameter (P = .001), smaller inclination angle (P = .003), larger retroversion angle of the humeral head (P < .001), and smaller glenoid length and width (P < .0001). Most of the implant companies did not have smaller sized combinations of humeral heads with thickness to match our population. The glenoid width of females in our cohort was found to be smaller for the smallest size of the glenoid base plate. CONCLUSION: Smaller sized options in humeral head diameter and thickness of the anatomic prosthesis and glenoid baseplate of the reverse shoulder prosthesis need to be made available to suit our population and avoid a mismatch.