This chapter aims to analyze works in the literature that show the therapeutic effects of using the Leap Motion Controller (LMC) sensor to assess hand fine motor dexterity, especially those involving the Box and Blocks Test. Besides the introduction, we will describe: (a) the LMC device and its forms of interaction in a Virtual Reality environment (immersive and non-immersive); (b) aspects of manual function assessment; (c) the functioning of the traditional Box and Blocks Test (BBT) and its virtual version (VBBT) developed with Virtual Reality technologies; (d) discussion about the VBBT integrated with the LMC, in physical therapy practice.