Bunnel Test for Intrinsic Tightness

- See:
       - Intrinsic Plus Finger
       - Lumbical Plus Finger
       - Phalangeal Injury

- Discussion:
    - lumbical plus finger should be distinguished from intrinsic plus finger;

- Clinical Presentation:
    - gripping medium-sized objects such as hammer handle is done primarily through IP joint flexion because handle effectively blocks MP joint from achieving full flexion;
    - pts w/ intrinsic tightness will become symptomatic when repetitively using this grip configuration against resistance;

- Technique:
    - intrinsic tightness is demonstrated by comparing passive PIP joint flexion w/ MP joint held in extension and then flexion;
    - test for intrinsic tightness is performed by passively holding pt's MCP joints extended & either actively or passively flexing PIP joints;
    - since intrinsics are put on stretch by MCP extension, if they are tight, IP joints will have limited flexion;
    - if PIP joint flexion is restricted when MP joint is held in extension but not when MP joint is held in flexion, pt has positive intrinsic tightness test;
    - attempts at active digital extension characterized by hyperextension of MP joint w/ simultaneous flexion of the PIP joint;
    - when MP joint are held in flexion, active extension of IP joint is normal

Original Text by Clifford R. Wheeless, III, MD.

Last updated by Data Trace Staff on Thursday, September 20, 2012 2:25 pm