The study evaluates patients with clinical evidence of post-surgical hematoma / seroma after hip replacement surgery. These patients will undergo ultrasound evaluation in the 4th (+/- 2) day post surgery, in which triaxial parameters of the hematoma will be measured. This evaluation will then be repeated after 5 treatment sessions with ENF (Electro Neuro Feedback). The patient will then be subjected to evaluation scales that allow to evaluate the subjective improvement of the state of well-being after treatment ENF (Electro Neuro Feedback) generates waveforms that change automatically when the impedance of the skin changes according to a compensation algorithm, i.e. according to Feedback (Feedback). T

Inclusion Criteria:

• Gender: male and female
• Age: 35-85 years include
• Entry into the hospital rehabilitation program lasting at least 5 days following hip replacement surgery
• Absence in history of neurological or psychiatric disorders.
• Signature of the Informed Consent and consent to collaborate in all the procedures of the study

Exclusion Criteria:

• Presence of severe neurological / psychiatric pathologies
• to sign the Informed Consense
• of serious cardiological pathologies that can compromise patient safety
• of Pace Maker or spinal cord stimulators or other subcutaneous electronic instruments
• of active tumors in the treatment area

The population is made up of patients who have undergone hip prosthesis surgery with the presence of post-surgical hematoma who are included in the hospital rehabilitation program lasting at least 5 days following this intervention.