Comparison of the efficacy of ultrasound-guided dextrose 25% hypertonic prolotherapy and intra-articular normal saline injection on pain, functional limitation, and range of motion in patients with knee osteoarthritis; a randomized controlled trial.

Abstract

Background and aims: Knee osteoarthritis (OA) is a debilitating condition that manifests as knee pain and dysfunction. Clinicians prefer non-surgical options such as intra-articular injections for mild to moderate disease. Dextrose prolotherapy (DPTx) has been shown to have a beneficial effect on knee OA in the long-term. In this randomized controlled trial (RCT), we aimed to compare DPTx with intra-articular normal saline injection (IA-NS) to treat knee OA in terms of effectiveness and patient-reported outcomes.

Methods: The study was a double-blind RCT with an allocation ratio of 1:1. We used block randomization to assign patients to each treatment arm. Patients with a visual analog scale of at least 4 for pain, and a Kellgren-Lawrence scale of grade 2 or 3 (mild or moderate disease) were selected and assessed according to eligibility criteria. The participants received either 5 ml of 50% dextrose water or 5 ml of 0.9% sodium chloride. The patients were followed up at 2, 4, and 8 weeks. SPSS software was used for statistical analyses. All results were reported with a confidence interval of 95%, and a p-value of less than 0.05 was considered significant.

Results: Overall, 55 patients were included in the study, but 50 completed the study process (25 patients in each treatment arm). The mean age of patients with knee OA was 62.98 ± 5.37, ranging from 55 to 74 years. We observed significant improvement in both groups in terms of knee pain, function, and knee extension degree at all follow-up visits (p < 0.001). Although DPTx was associated with better results than IA-NS, the difference was not statistically significant (p > 0.05). The adverse events were limited to injection-site pain and ecchymosis, which resolved by week 4.

Conclusion: Although we achieved slightly better results with DPTx, this treatment technique was not clinically or statistically superior to IA-NS in terms of knee pain and function in the short-term. Therefore, both DPTx and IA-NS are effective and well tolerated treatment options for knee OA. However, more RCTs are needed to confirm these claims.