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.
Lying position (anatomical):
The least popular position for testing offers good range of motion but limited as the elbow is straight rather than bent (which is when most supination in real life occurs). This was the original position of choice for research as the shoulder could be more easily stabilized. Stabilisation with an upper arm support and chest strap.
Seated Position:
The most popular position as it tends to be the most comfortable. Although this position is not as stabilised as lying it does allow as large a range of motion it is also much more functional and gives the most usable results. The shoulder must be closely monitored for movement as must the elbow, however, if the elbow is overly stabilized then the range of motion will be restricted (remember not to increase the intra-muscular pressure in the forearm too much by over stabilizing the elbow). Try to get the elbow to as close as 90 degrees as possible for the test (this is the angle of peak torque for the biceps at the elbow which gives them mechanical advantage in this position). Best for patients.
To view a set up video see below:
One of the main consideration is the height of the shoulder girdle. Most authors recommend neutral as the optimal position it is best to be guided by subject comfort try to avoid elevation or depression.
Standing position:
In the standing position stabilization is difficult if not impossible (and probably undesirable). Testing in this position is more functional than that in any other position expect correlation coefficients to be as low as 0.71.
Stabilisation:
Because of the mobility of the wrist and hand it is possible to circumduct the wrist in one direction or the other. This adds to pronation and supination. Circumduction is a combined motion and should be prevented during testing because it is not reproducible.
Lying: In the lying position stabilisation normally only involves a arm support and the chest straps to prevent the torso from influencing the results. It is likely the shoulder will move during the test it can be held manually.
Seated: in the seated position stabilisation usually involves an elbow pad and an elbow strap.
Standing: Stabilisation in the standing position is not normally required as this is the most functional position.
Attachments:
The hand grip should be used
Axis of rotation:
The axis of rottion bisects the head of the ulna distally and the head of the radius proximally. In essence the ring finger (3rd finger) needs to be in a line with the actuator axis.
Anatomical zero:
Thumb pointing upwards
Range of motion:
Gallagher et al (1997) suggest a -50 to +50 degree range of motion, however, this can be hard to achieve and a -30 to +30 degree range seems more common.
Gravity correction:
Not required.
Speeds:
As velocities in some sports (any involving throwing an object) are known to reach thousands of degrees/second (Pappas et al., 1985) testing using a dynamometer has been said to be non-functional. However, speeds over 300 degrees/second have been found to be difficult to achieve by even baseball pitchers (Cook et al., 1987). This could be said to suggest that muscular effort starts the motion but only occurs at slower speeds with momentum and acceleration playing a larger role later in the speed of the motion later through range rather than pure strength. Even if this speed could be achieved it is over such a small arc that the results gained would likely be fruitless.
Generally it is accepted that speeds of 30 degrees/second are slow with 60 degrees a standard test speed. Any speed up to 190 degrees/second is achievable but speeds over this are hard to maintain.
Pronation / Supination Protocols:
Muscles involved:
Pronators and supinator
| Strength Test Protocols | General | Patients | Athletes | Research |
| Contraction Cycle | con/con | con/con | con/concon/ecc | con/conecc/ecc |
| Speed/s | 60 or 120 | 60 or 120 | 60-300 | 60-500 |
| Trial Repetitions | 0 | 0 | 0 | 3 |
| Repetitions | 10 | 10 | 10 | 5 |
| Sets | 3 | 3 | 4 | up to 9 |
| Rest between sets | 20-30 secs | 20-30 secs | 20-30 secs | 20 secs |
| Rest between speeds | 2 minutes | 2 minutes | 2 minutes | 2-5 minutes |
| Rest between sides | 5 minutes | 5 minutes | 5 minutes | 5 minutes |
| Feedback | nil | nil | nil | nil |
| Endurance Test Protocols | General | Patients | Athletes | Research |
| Contraction Cycle | con/con | con/con | con/concon/ecc | con/conecc/ecc |
| Speed/s | 120 | 120 | 120-300 | 120-500 |
| Trial Repetitions | 0 | 0 | 0 | 0 |
| Repetitions | Max | Max | Max | Max |
| Sets | 1 | 1 | 1 | 1 |
| Rest between sets | N\A | N/A | N/A | N/A |
| Rest between speeds | 10-15 mins | 10-15 mins | 10-15 mins | 10-30 mins |
| Rest between sides | 5 mins | 5 mins | 5 mins | 5 mins |
| Feedback | nil | nil | nil | nil |
| Strength Exercise Protocol | General | Patients | Athletes |
| Contraction Cycle | con/con | con/con | con/ecc |
| Speed/s | 60 up to 180 | 60 up to 180 | 60-300 |
| Trial Repetitions | 0 | 0 | 0 |
| Repetitions | 10 | 10 | 14 |
| Sets | 6 | 6 | up to 12 |
| Rest between sets | 30-60 secs | 30-60 secs | 30 secs |
| Rest between speeds | 2 mins | 2 mins | 2 mins |
| Rest between sides | Nil | Nil | Nil |
| Feedback | bar | bar | bar |
| Endurance Exercise Protocol | General | Patients | Athletes |
| Contraction Cycle | con/con | con/con | con/con |
| Speed/s | 120-180 | 120-180 | 120-300 |
| Trial Repetitions | 0 | 0 | 0 |
| Repetitions | Max | Max | Max |
| Sets | 1-3 | 1 | 1-3 |
| Rest between sets | 5-10 mins | N/A | 5-10 mins |
| Rest between speeds | 10-30 mins | N/A | 10-30 mins |
| Rest between sides | Nil | Nil | Nil |
| Feedback | bar/pie chart | bar/pie chart | bar/pie chart |
Notes:
Test the uninvolved or dominant limb first.
A very difficult movement to localize, care must be taken when analyzing the results as this is an under researched area.
Interpretation:
In the forearmit is normal to look at the ratio between the right and left sides there should be a 0-10% difference between the sides. Anything beyond this would either demonstrate extreme hand dominance (this can happen in certain sports like javelin), or indicate a muscle imbalance which would be best corrected.
Eccentric results are generally 30% higher than concentric within the same muscle Ivey et al (1985) Davies (1984).
Generally the pronators are stronger than the supinators by 10% however results do ary between 30% stronger to 5% weaker
Angle of peak torque for pronation is aproximatly-8 degrees and peak supination occurs at +12 degrees (Gallagher et al 1997).
Normative values:
| Ellenbecker et al (2006) | Age | Sex | Machine | PTBW (SD) | |
| speed deg/s | 12-16 | f | Cybex | Supination/Pronation ratio | |
| 90 Non Dominant | 104.1 (32.5) | ||||
| 210 | 125.62 (53.9) | ||||
| 90 Dominant | 62.25 (25.1) | ||||
| 210 | 64.59 (24.1) | ||||
Pronation concentric strength (subjects tested seated)
| Female | Male |
| Non Dominant | ||
| 60/sec | 7 | 12 |
| 120/sec | 6 | 10 |
| 180/sec | 5 | 9 |
| Female | Male |
| Dominant | ||
| 60/sec | 8 | 13 |
| 120/sec | 7 | 12 |
| 180/sec | 6 | 11 |
Supination concentric strength (subjects tested seated)
| Female | Male |
| Non Dominant | ||
| 60/sec | 6 | 10 |
| 120/sec | 5.5 | 5 |
| 180/sec | 5 | 8 |
| Female | Male |
| Dominant | ||
| 60/sec | 5 | 11 |
| 120/sec | 9 | 10 |
| 180/sec | 4 | 9 |
Adapted from Hartsell, Hubbard and Van Os (1995)