What joint does the tight retinacular test focus on?

The tight retinacular test specifically assesses the function and mobility of the structures surrounding the proximal interphalangeal (PIP) joint. In this test, the clinician evaluates the ability of the distal interphalangeal (DIP) joint to flex when the PIP joint is held in extension. A positive result indicates that there may be tightness in the retinacular ligaments and potentially a functional limitation that can affect hand function.

This test is particularly important because normal movement at the DIP joint relies on the proper length and function of the retinacular ligaments, which connect the PIP joint to the DIP joint. If the PIP joint is unable to flex the DIP joint adequately, it suggests a restriction in the surrounding soft tissues, rather than a purely intrinsic problem with the DIP joint itself. Therefore, the focus of the tight retinacular test is indeed on the PIP joint, revealing its influence on the movements of the DIP joint.