Clinical Report: Inulin and Physiotherapy Reduce Knee OA Pain Independently
Overview
In a 6-week randomized controlled trial involving 117 patients with knee osteoarthritis, both inulin supplementation and physiotherapy-supported exercise independently reduced pain by clinically meaningful amounts. No synergistic effect was observed when combining the two interventions, though each demonstrated distinct benefits on physical performance and pain sensitization.
Background
Knee osteoarthritis (OA) is a common degenerative joint disease characterized by pain and functional impairment. Management strategies often include physiotherapy-supported exercise to improve mobility and reduce pain. Nutritional interventions such as inulin supplementation have been proposed to modulate pain through gut microbiota and metabolic pathways. Understanding the comparative and combined effects of these interventions can inform holistic OA treatment approaches.
Data Highlights
Intervention
Change in Pain (NRS, points)
30-sec Sit-to-Stand (repetitions)
Timed Up-and-Go (seconds)
Grip Strength (units)
Dropout Rate (%)
Placebo
Reference
Reference
Reference
Reference
Not specified
Inulin
−1.11
Not significant
Not significant
+4.62
3.6
Physiotherapy-Supported Exercise
−1.55
+2.76
−0.66
Not significant
21
Combined (Inulin + Physiotherapy)
−1.67
Not specified
Not specified
Not significant
Not specified
Key Findings
Both inulin supplementation and physiotherapy-supported exercise significantly reduced knee OA pain compared with placebo, exceeding the minimal clinically important difference of 1 point on the Numerical Rating Scale.
No synergistic pain reduction effect was observed when combining inulin with physiotherapy-supported exercise.
Physiotherapy-supported exercise improved physical function, increasing sit-to-stand repetitions by 2.76 and reducing timed up-and-go by 0.66 seconds.
Inulin supplementation improved grip strength by 4.62 units and was associated with higher pressure pain thresholds and reduced temporal summation, indicating effects on central sensitization.
Inulin increased circulating butyrate and GLP-1 levels; higher GLP-1 correlated with improved grip strength in exploratory analyses.
Dropout rates were substantially lower in the inulin group (3.6%) compared to the physiotherapy group (21%), with minor gastrointestinal side effects reported for inulin but no withdrawals due to adverse events.
Clinical Implications
Clinicians may consider inulin supplementation as a complementary approach to physiotherapy-supported exercise for knee OA pain management, particularly for patients who may have difficulty adhering to exercise programs. The distinct mechanisms of action suggest that dietary interventions targeting gut-derived metabolites and central sensitization could provide additional benefits beyond physical rehabilitation. Monitoring for minor gastrointestinal symptoms with inulin is advised but generally well tolerated.
Conclusion
Inulin supplementation and physiotherapy-supported exercise each independently improve pain and function in knee osteoarthritis without synergistic interaction. Integrating dietary and physical interventions offers a promising, holistic strategy for OA management.
References
Kouraki et al. 2024 -- Knee OA Pain: Inulin vs Physiotherapy Effects
