The article by Oztas and colleagues about the effect of repeated ultrasound to treat carpal tunnel syndrome (CTS) causes me concern. As physiatrists, we are aware of the heating effects of therapeutic ultrasound and thus would routinely avoid ordering its use directly over compromised nerves, since this could aggravate the condition. For example, we would not want to use ultrasound directly over a compressed nerve root with active radiculopathy. Therefore, I am uncertain why the authors studied ultrasound in this manner. The authors failed to note that appropriate use of ultrasound has been reported in the literature for treatment of entrapment neuropathy in humans. As noted in that report, it is important to avoid placing the ultrasound over the center of the carpal canal because direct heating of the median nerve could lead to increased inflammation. The ultrasound should be directed around the canal, along the edges. In this manner, the ultrasound renders the transverse carpal ligament and other structures more elastic and responsive to the manipulation and exercise. The report by Oztas and colleagues demonstrated that there is a difference between use of ultrasound over the nerve for a direct healing effect versus use around the nerve to allow release of structures compressing the nerve. The latter effect can relieve pressure and allow the nerve to heal spontaneously.
Sucher, B. M. (1999). Ultrasound therapy effects in CTS . Archives of Physical Medicine and Rehabilitation. W.B. Saunders. https://doi.org/10.1016/S0003-9993(99)90071-0