Abnormal lymphatic system function in patients with chronic neck and shoulder pain: neuroimaging evidence from DTI-ALPS.

Objective: Chronic neck and shoulder pain (CNSP) is frequently associated with structural and functional brain damage that progressively worsens over time. The glymphatic system (GS), a gel-like extracellular fluid in the brain, plays a crucial role in clearing waste products and maintaining interstitial fluid homeostasis. However, its relationship with CNSP remains unclear. This study employed diffusion tensor imaging along perivascular spaces (DTI-ALPS) to investigate functional changes in the lymphatic system among patients with chronic neck and shoulder pain, while exploring potential correlations with clinical outcomes. Methods: This study enrolled 20 patients with CNSP and 20 healthy controls (HCs). All participants underwent standardized scans using a 3.0T MRI scanner. By calculating the bilateral DTI-ALPS indices of the two groups, we compared the functional status of GS between the groups and further established its correlation with clinical indicators. Results: Following a permutation test (10,000), the DTI-ALPS index in the left cerebral hemisphere of the CNSP group was significantly lower than that in the HCs group ( Conclusion: Our findings indicate that CNSP may lead to abnormal GS function in the left hemisphere as the disease duration prolongs and pain intensity increases.