Trial results for a study investigating molecular pathways involved in knee pain in patients with Osteoarthritis were posted on ClinicalTrials.gov on 2025-08-13, with 71 participants enrolled.
Background
Knee osteoarthritis (OA) is recognized as the most common form of arthritis and a primary cause of knee pain globally, with prevalence rates comparable to cardiac disease, particularly in individuals over 65. A significant factor complicating the clinical picture and potentially impacting treatment outcomes is Central Sensitization (CS). CS is characterized by widespread pain sensitivity that can manifest throughout the central nervous system, leading to alterations in the spinal cord and brain. Its presence is noted in more than 20% of patients with knee OA, suggesting a distinct pain processing profile that warrants further investigation.
Trial design
This completed study enrolled 71 participants to investigate conditions including Knee Osteoarthritis and Knee Pain Chronic. The study aimed to explore molecular pathways involved in knee pain, specifically differentiating between individuals with and without prevalent central sensitization. The measurements collected focused on various aspects of pain sensitivity and psychological factors associated with pain.
Key results
The trial reported several key measurements comparing participants with prevalent central sensitization to those without:
- Pain Sensitivity: Pressure Pain Detection Threshold (PPT) (kPa):
- For the Prevalent Central Sensitisation group, the mean was 252.58 (Standard Deviation 124.41).
- For the Non-prevalent Central Sensitisation group, the mean was 266.17 (Standard Deviation 93.82).
- Pain Sensitivity: Temporal Summation Pain (TS) (score on a scale):
- For the Prevalent Central Sensitisation group, the mean was 4.26 (Standard Deviation 0.71).
- For the Non-prevalent Central Sensitisation group, the mean was 0.91 (Standard Deviation 0.83).
- Pain Sensitivity: Conditioned Pain Modulation (CPM) (kPa):
- For the Prevalent Central Sensitisation group, the mean was 73.66 (Standard Deviation 92.05).
- For the Non-prevalent Central Sensitisation group, the mean was 13.85 (Standard Deviation 137.71).
- Central Aspects of Knee Pain (CAP-Knee) (Score on a scale):
- For the Prevalent Central Sensitisation group, the mean was 8.9 (Standard Deviation 3.4).
- For the Non-prevalent Central Sensitisation group, the mean was 6.2 (Standard Deviation 2.4).
- Anxiety (score on a scale):
- For the Prevalent Central Sensitisation group, the mean was 6.00 (Standard Deviation 3.67).
- For the Non-prevalent Central Sensitisation group, the mean was 5.56 (Standard Deviation 2.94).
- Depression (score on a scale):
- For the Prevalent Central Sensitisation group, the mean was 4.00 (Standard Deviation 3.12).
- For the Non-prevalent Central Sensitisation group, the mean was 5.15 (Standard Deviation 2.74).
What this means
The results from this study highlight distinct differences in pain sensitivity and central pain processing between individuals with knee osteoarthritis who exhibit prevalent central sensitization and those who do not. Notably, the group with prevalent central sensitization showed a substantially higher mean score for Temporal Summation Pain (TS) (4.26 vs. 0.91) and a higher mean score for Central Aspects of Knee Pain (CAP-Knee) (8.9 vs. 6.2). These findings suggest that central sensitization is associated with increased pain amplification and a greater central component to knee pain. While differences in Pressure Pain Detection Threshold (PPT) and Conditioned Pain Modulation (CPM) were also observed, the larger standard deviations indicate more variability within these measures. Anxiety scores were slightly higher in the prevalent central sensitization group, while depression scores were slightly lower in this group. These distinctions underscore the importance of assessing central sensitization in knee OA patients to better understand their pain experience and potentially tailor treatment approaches.
Source
The information regarding these trial results was obtained from ClinicalTrials.gov, a public database of clinical studies. The results for the study NCT04443452, titled "Molecular Pathways Involved in Knee Pain", were posted on 2025-08-13 on clinicaltrials.gov.