Ultrasound-guided platelet-rich plasma injection improves pain, function and symmetry in lumbar myofascial pain syndrome: A case report

Figure 5 The surface electromyography of the bilateral quadratus lumborum revealed improved symmetry in both time-domain and frequency-domain analyses following platelet-rich plasma treatment compared to pretreatment measurements. The frequency-domain analysis demonstrated a significant reduction in muscle fatigue at the 6-month follow-up assessment. A: Surface electromyography (sEMG) time domain analysis of quadratus lumborum (QL) before treatment; B: sEMG frequency domain analysis of QL before treatment; C: sEMG time domain analysis of QL at 6-month follow-up after treatment; D: sEMG frequency domain analysis of QL at 6-month follow-up after treatment.