Commander Muscle Tester PowerTrack II
JTech Power Track II
The Commander PowerTrack II manual muscle tester is a brilliant dynamometer for clinical and research purposes, used extensively in Australia and internationally. This JTech hand held dynamometer has been extremely popular among Australian universities, Australian national and state sporting associations, Australian hospitals, and private clinics. Consisting of a wrist console and a hand held dynamometer (transducer), it allows fast and accurate testing of isometric muscle strength. The digital wrist console stores and analyses up to 40 bilateral tests. The PowerTrack II (written PowerTrack rather than Power Track) is designed to measure forces using either the make or brake isometric strength measuring techniques.
Importance & Reliability of the PowerTrack Hand Held Dynamometer
When testing a patient who you suspect is impaired on one side, with manual muscle testing (MMT) one might be able to say that the impaired side is weaker than the unimpaired side, but the unimpaired side may not be normal either! Thus it is important to test using the PowerTrack as it provides a numerical objective measure of force.
Researchers have used hand held dynamometers like the PowerTrack to compile databases on populations of normals. These databases record how many Newtons force particular muscle groups generate in specified age groups. Databases exist for stating if the strength of the limbs are within the normal range or not. Using these databases and their regression equations one is able to say if a 67 year old male patient who has a body weight of 765 Newtons and an elbow flexion force on his non-dominant side of 130.8 N is impaired or not. In this case the patient's force is actually 46.5% below the predicted value and more than two standard deviations below the mean values for his age group.
This is obviously a lot more informative than merely saying his non-dominant side is weaker than his dominant side! It is also much more informative than merely saying he has a ranking of Grade 2 as measured using a five point subjective MMT scale. Also it should be noted that if the MMT score differs by only one grade this represents an error of 20% in a five-grade system.
Some researchers have found that therapists using MMT could not distinguish knee extensor forces that varied as much as 25%, and that they graded as normal patients who had lost as much as 50% of the muscle's tension production. The PowerTrack hand held dynamometer has been used to measure hip abduction and adduction isometric strength in elite soccer players, in order to help prevent groin injuries.
The PowerTrack II Commander Manual Muscle Tester unit consists of:*
- PowerTrack II dynamometer and wrist console
- Battery supplied
- Spiral bound Flip Chart
- Spiral bound Users Manual
- Formatted pad for manual recording of results
- Two transducer heads (one scooped and one flat & round)
- Two leads (one short and one long) for connecting the transducer to the wrist console.
- A hard, foam cushioned carry case
*Contents may vary without notification.
Our JTECH Medical muscle testing dynamometers have an Australian Register of Therapeutic Goods Certificate wth the Therapeutic Goods Administration (TGA); ARTG Identifier 277071. This certificate only applies to these hand held dynamometers in Australia if they are imported by Australasian Medical & Therapeutic Instruments Pty Ltd.
Please refer to the following document for details of published studies that have involved the PowerTrack dynamometer.