Sixty patients with chronic low back pain were randomized to receive either monopolar dielectric diathermy by radiofrequency combined with supervised therapeutic exercise (n=30) or supervised therapeutic exercise alone (n=30). The primary outcome was disability measured by the Roland Morris Disability Questionnaire. Secondary outcomes included Oswestry Disability Index, pain (VAS), kinesiophobia (TSK), quality of life (SF-36), sleep quality (PSQI), emotional distress (HADS), trunk flexor muscle endurance (McQuade test), and lumbar mobility. Outcomes were assessed at baseline, post-treatment (4 weeks), and 12 weeks. Overall, the results revealed that adding diathermy to exercise significantly improved pain, disability, kinesiophobia, muscle endurance, and several domains of quality of life compared to exercise alone. These findings suggest that diathermy plus exercise is more effective and provides more sustained benefits than exercise alone.