College of Massage Therapists of British Columbia (CMTBC) Practice Exam

At the glenohumeral joint, which range of motion is greater during CPR assessments?

1. Flexion

2. External Rotation

3. Abduction

4. Internal Rotation

The correct answer is: External Rotation

During CPR assessments, the range of motion that is typically greater at the glenohumeral joint is external rotation. This is largely due to the position required when performing chest compressions, which often involves lifting and positioning the arms to facilitate optimal mechanics and access to the chest area. When a person is lying flat on their back, as found in CPR scenarios, the arms must often be placed in a way that effectively exposes the chest while maintaining enough supportive positioning to enable effective compressions. The use of external rotation allows for a more efficient alignment of the shoulders and arms to maximize force generation during compressions. Additionally, external rotation at this joint can facilitate a better mechanical advantage and alignment for rescuers, allowing for deeper compressions and reducing fatigue during the process. This range of motion can sometimes be greater than others like flexion, abduction, or internal rotation, which may not be as required in this specific life-saving context.