Efficacy of photobiomodulation in relieving postoperative pain in patients with knee osteoarthritis undergoing total knee replacement

Abstract

Purpose: To evaluate the efficacy of photobiomodulation in reducing opioid consumption after total knee replacement in patients with knee osteoarthritis. Secondarily, also to evaluate pain, early adverse effects and patient’s satisfaction with the analgesia. Methods: Ten patients with knee osteoarthritis were submitted to primary total knee replacement under spinal anesthesia and sedation. Among postoperative analgesia, all patients received ultrasound guided obturator and femoral nerve blockage, dipyrone 30mg/kg intravenous (IV) every 6 hours and ketorolac 30mg IM every 12 hours for 3 days. If still with pain patients could receive IV morphine 2mg by a patient control analgesia (PCA) device. photobiomodulation (PBM) was applied in nine patients with a Light Aid equipment from Bright Photomedicine-Brasil, arsenide, gallium and aluminum LEDs. Patients received sessions of PBM at the immediate postoperative (in the operating room) and after 48 hours. The Waves were of 850nm length and it was applied in the topography of the femoral nerve for 240 seconds and parallel to the surgical incision of the knee for 120 seconds. One patient received placebo PBM. Results: The patient that received placebo PBM consumed 12mg, 22mg, 20mg and 4mg at immediate postoperative (IPO), 1st, 2nd, and 3rd PO day, respectively. The group that received PBM, received on average 3.5mg±4.8, 8.4mg±5.32, 1.56mg±2.37 and 0mg of morphine respectively at IPO, 1PO, 2PO, 3PO. Pain at rest averaged 4.8±3.2 and 5.6±3.5 at movement at IPO evaluation for the PBM group whereas the patient that received placebo treatment referred pain 8 at rest and 10 at movement. Four patients reported pain above 8 at least once during follow-up, while the remaining reported pain 5 at most once. In average the 9 patients that received PBM graded their satisfaction with the analgesia as 7.9±2.4 while the patient that received placebo with a 2. Two patients had nausea and itching, two only nausea and one only itching. All symptoms were subsided without the need of new procedures or increased hospitalization. Conclusions: There is an actual potential of using photobiomodulation as a tool to reduce pain and increase mobility of patients with knee osteoarthritis undergoing total knee replacement.