Validity and Reliability of a Hand-Held Dynamometer for Dynamic Muscle Strength Assessment

To overcome the limitations of the MMT, isometric hand-held dynamometers (HHD) have been developed to aid therapists in clinics (Andrews (1991)). HHDs are generally small and portable, and measure strength objectively in kilograms, pounds or newtons. The clinician holds the HHD between his or her force-applying hand and the patient’s limb segment. The clinician stabilises the limb segment while encouraging the patient to exert as much force against the device as possible and the maximum force is recorded by the HHD. Such devices have been proven to have good to excellent reliability in different populations (Andrews (1991); Bohannon & Andrews (1987); Stark et al. (2011)). In a single test, however, they can assess the strength of a patient at only one joint angle, rather than through the patient’s entire ROM. Although this technique provides a crucial tool for clinical quantification of joint strength at a fixed static position (isometric), it cannot measure properties from dynamic muscle performance assessments.