Elson`s Test

Elson’s Test is a diagnostic examination for the early detection of central slip injuries in the extensor tendon of the hand. Central slip injuries can be easily overlooked until a Boutonnière deformity develops, which results in significant functional limitations¹,².

Elsons test

Execution of the Test

• Patient position: The patient rests the hand on a table

• Finger position:

  • The proximal interphalangeal joint (PIP joint) of the affected finger is flexed to 90° over the edge of the table

• Examiner:

  • Palpates the middle phalanx of the involved finger

  • Instructs the patient to extend the PIP joint against resistance

Video av utførelse av Elsons test

Interpretation of Results

• Positive test:

  • Weak extension at the PIP joint

  • (Hyper)extension at the distal interphalangeal joint (DIP joint) → indicates a central slip injury

• Negative test:

  • Strong extension at the PIP joint

  • DIP joint remains flaccid → no central slip injury

Evidence and Diagnostic Value

• A cadaver study analyzing four non-invasive tests for central slip integrity found that Elson’s Test was the only one that accurately identified injury in simulated conditions²

• This supports its high diagnostic value for early detection of extensor tendon injury

Summary

Elson’s Test is a simple and highly specific clinical maneuver for detecting central slip injuries in the extensor tendon. A positive finding helps clinicians identify injury before a Boutonnière deformity develops, allowing for earlier intervention and improved functional outcomes.

Sources

1. Elson RA. Rupture of the central slip of the extensor hood of the finger. A test for early diagnosis. J Bone Joint Surg Br. 1986 Mar;68(2):229-31. doi: 10.1302/0301-620X.68B2.3958008. PMID: 3958008.

2. Rubin J, Bozentka DJ, Bora FW. Diagnosis of closed central slip injuries. A cadaveric analysis of non-invasive tests. J Hand Surg Br. 1996 Oct;21(5):614-6.