Therapeutic effects of prolotherapy with intra-articular dextrose injection in patients with moderate knee osteoarthritis: a single-arm study with 6 months follow up

Objectives: Prolotherapy is an injection-based complementary treatment, which has shown promising results in the treatment of different musculoskeletal disorders. The aim of this study was to determine the therapeutic efficacy of dextrose prolotherapy on pain, range of motion, and function in patients with knee osteoarthritis (OA).

Methods: In this single-arm prospective study, participants with symptomatic moderate knee osteoarthritis underwent prolotherapy with intra-articular injection of 20% dextrose water at baseline, and at 4 weeks and 8 weeks later. Patients were followed for 24 weeks. Pain severity at rest and activity, according to the visual analog scale (VAS), articular range of motion (ROM), and Western Ontario and McMaster Universities arthritis index (WOMAC) scores were measured at baseline, 4, 8, and 24 weeks later.

Results: A total of 24 female patients (average age: 58.37 ± 11.8 years old) received 3-monthly injection therapies. Before the treatment, the mean articular range of motion was 105.41 ± 11.22°. Mean VAS scale at rest and activity was 8.83 ± 1.37 and 9.37 ± 1.31, respectively. At the end of week 24, knee ROM increased by 8°. Pain severity in rest and activity decreased to 4.87 ± 1.39, 45.86%, and 44.23%, respectively (p < 0.001). Total WOMAC score and its subcategories showed a continuous improvement trend in all the evaluation sessions, so that at the end of the study, the total score decreased by 30.5 ± 14.27 points (49.58%) (p < 0.001). Improvements of all parameters were considerable until week 8, and were maintained throughout the study period.

Conclusions: Prolotherapy with three intra-articular injections of hypertonic dextrose given 4 weeks apart for selected patients with knee OA, resulted in significant improvement of validated pain, ROM, and WOMAC-based function scores, when baseline levels were compared at 24 weeks. Further studies with randomized controlled trials involving a comparison group are suggested to confirm these findings.