The two-point discrimination test--time for a re-appraisal?

The two-point discrimination (2PD) test is the most frequently used test for the assessment of the sensory outcome after nerve repair. Here we focus on factors which explain the enormous and implausible variability in reported 2PD levels after nerve repair. We conclude that the 2PD testing technique is not at all standardized and that its use as the sole test for tactile gnosis recovery should be seriously questioned. Reports of 2PD results should always be accompanied by a detailed description of how the test was performed, especially with reference to the pressure applied and the testing protocol.