Duloxetine in Addition with Platelet Rich Plasma in Managing Neuropathic Knee Pain: A Comparative Study

Abstract

Background: Osteoarthritis of knee joint is one of the most prevalent forms of arthritis in the world. With the progressive ageing of the population, it becomes a major public health concern. Knee osteoarthritis with neuropathic pain further increase the sufferings resulting functional limitation. Various conservative and intra-articular therapies have been used but none proved to be ideal for the treatment of chronic osteoarthritis. Current research in investigating new methods for stimulating repair or replacing damaged cartilage by using biological agents like platelet rich plasma in chronic osteoarthritis. Combination of platelet rich plasma therapy along with orally given duloxetine can provide better outcome for neuropathic pain and functional limitation.
Methods: This study was carried out in the Pain Clinic, Department of Anaesthesia, Analgesia and Intensive Care Medicine, BSMMU during the period of May 2019 to April 2020. The patients were randomly assigned to one of the two groups (group A= only intra articular PRP; group B= PRP with oral Duloxetine 20mg) using a computer generated random sampling. After providing the allocated treatment, all patients were undergone follow-up examination at 1st week, 1st month and 3rd month after the procedure by International Knee Documentation Committee (IKDC) score, DN4 questionnaire and VAS scale. Pain intensity and neuropathic pain status were assessed by visual analog scale (VAS) and DN4 questionnaire. Whereas IKDC score was used to assess functional impairment of affected knee joint. Follow up were carried out by visiting in Pain Clinic at mentioned intervals or over phone. The significance of the difference of the DN4 score, visual analogue scale (VAS) and International Knee Documentation Committee (IKDC) score at 1st week, 1st month, and 3rd month were tested by using unpaired t- test, chi-square test and fisher exact test.
Results: To assess functional improvement of affected knee joint, group B mean IKDC score was more than Group A in all follow up period, but statistically significant results were observed in 1st month (50.92±3.85) and 3rd month (55.54±4.64) follow up. Mean DN4 score and VAS score at pretreatment and 1st week were not statistically significant between the groups. But at 1st month and 3rd month both DN4 score and VAS score showed statistically significant difference between the groups. Inter group comparison showed that, mean DN4 score in group B (2.45±0.59) grossly decreased than group A (5.20±0.51) which indicate statistically significant reduction of neuropathic pain between the groups. Group B mean VAS (2.15±0.36) score decreased more than Group A (4.75±0.43) showed statistically significant improvement of pain in group B than group A.
Conclusion: Intra articular platelet rich plasma in combination with oral duloxetine provide better pain relief and improvement of functional status than PRP alone in chronic knee osteoarthritis with neuropathic pain.