In an our previous article, we described a case of a professional swimmer who presented a pneumothorax after treatment with dry needling (DN), performed by a physiotherapist. Although only few cases of serious adverse events after this treatment are reported in literature, the description of this case seemed to us of considerable interest to underline and discuss the medical-legal and ethical aspects regarding the skills and responsibilities of medical doctors and physiotherapists performing the procedure. The doctor-patient relationship, in this case, has failed because the patient has not received a correct diagnosis and adequate rehabilitation treatment according to international guidelines. In Italy a specialist medical doctor's prescription is required as a guide in the rehabilitation program performed by the physiotherapist after a clear and official diagnosis. The Italian Council of Health in the session of 13 June 2017, established that the practice of DN is a doctor's exclusive competence due to the invasive characteristics and potential complications of this technique.