There are currently no standard examination positions for pronation and supination. During these movements the shoulder is difficult to fully stabilize without using 90 degrees of shoulder abduction and even then the subject can move the shoulder somewhat the elbow is usually flexed to 90 degrees during these tests (as described by Gallager et al 1997).
If isolated from the wrist and elbow the forearm has one degree of freedom. This is longitudinal through the two bones controlled by the superior and inferior raio/ulna joints. This motion allows radius to rotate moving the attached hand into the palm down (pronation) and palm up (supination positions.
These movements can be performed in either the lying, seated (most popular position), or standing positions. Most movements around the forearm in everyday life, and in fact sport, occur with the hand free in space (open chain) and with the elbow bent.
Supination of the forearm has been extensively studied in patient populations with biceps tendon problems. Supination is often investigated at the same time as elbow flexion the two are co-dependant.
These movements can be performed in either the standing, seated or lying (most popular position). Most movements around the elbow in everyday life, and in fact sport, occur with the hand free in space (open chain). The position of the elbow joint moves in space in relation to the shoulder which makes the two joints co-dependant. The action of flexion of the elbow also calls into play the wrist as stabilisation is required for the flexor muscles to function correctly.