Summary

What it measures:

A dynamometer is a handheld device that can measure the isometric strength of a specific function, muscle group, or individual muscle. 

Target Population:

Mixed populations

International Classification of Functioning, Disability and Health (ICF):

Category: Body Functions

Domain: Neuromusculoskeletal and movement-related functions; muscle power functions 

Type of Measurement: Clinician-administered

Clinical Insights

• The current gold standard for strength testing is via isokinetic dynamometry. Handheld dynamometry is a more cost-effective, portable, and space-saving objective method of testing strength. However, there is insufficient evidence to recommend handheld dynamometry as a standard due to questions regarding validity, accuracy, and differences in interrater reliability due to a lack of universally accepted standardized positions for different muscle groups.
• Handheld dynamometry is more objective and quantitative than manual muscle testing if an isokinetic machine is unavailable.
• A break test or a make test can be used to test the subject. It is important to document which testing method was used during objective measurement collection for reliability and reproduction. 
• The break test requires the ability of the examiner to apply enough strength to break the movement, while simultaneously reading the force measure at the exact moment the patient’s movement starts to break.¹
• The examiner strength must be great enough to perform the assessment.² 
• Stabilization is of utmost importance for reliability. The strength and size of the examiner can impact the reliability of outcomes.²