Test library › Elbow & forearm
Grip strength difference ≥10% (elbow extended vs flexed)
For: Lateral elbow tendinopathy
Painful overload of the wrist extensor tendons where they attach to the outside of the elbow. Also called tennis elbow.
Best used to rule inWhat the numbers mean
- Positive result: a moderate rule-in: a positive result makes the diagnosis clearly more likely.
- Negative result: a small shift: a negative result nudges the diagnosis down, but does not exclude it.
Source
Dorf ER, Chhabra AB, Golish SR, McGinty JL, Pannunzio ME. Effect of Elbow Position on Grip Strength in the Evaluation of Lateral Epicondylitis. J Hand Surg Am. 2007;32(6):882–886. Journal article (DOI) · single study
Figures as they will appear in Rule It In, Rule It Out (Trokos, forthcoming). If a newer or better study changes them, this page changes with the book. Figures last updated from the book on 2 October 2026.
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This page gives the published figures. Rule It In, Rule It Out adds how to do this test, what counts as positive, how to read the result, and, where studied, whether combining it with other tests helps.
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One study, one test, once a month
Rule It In is a free evidence letter for musculoskeletal clinicians: one recent study explained, one examination test with its real numbers. From Trokos, publisher of Rule It In, Rule It Out.