I have never heard of it, but I guess it is possible if the HVLA is performed recklessly. I would wonder if their decresed sensation is accompanied by muscle weakness, and also the pattern of sensation loss as they relate to dermatome segments of the brachial plexus. The brachial plexus is composed of spinal nerve roots C5 to T1, a pretty wide range of segments and spinal nerves to be compressed by a single HVLA technique. These individuals may have an underlying thoracic outlet problem which has been exacerbated by the stress of HVLA.