Background and aims: Pain is a debilitating sign of osteoarthritis (OA) and current pharmacological and surgical treatments are unsatisfactory. Whole body vibration (WBV) is a physical exercise-related therapy, which has been shown to decrease pain in OA patients, but the underlying mechanisms are unknown. This study aims to provide new insights into mechanisms of analgesic actions of WBV in the medial meniscal tear knee OA mouse model.
Methods: Experiments were performed in accordance with IASP guidelines and after approval by the local ethics committee. OA was induced by transection of the medial collateral ligament and medial meniscus in male and female C57BL/6J mice. Sham-operated and naïve mice served as controls. WBV was performed using a custom-made WBV apparatus (15 Hz and 0.3 g, 15 min/day, 5 days/week) for 13 weeks. Mechanical sensitivity was assessed by von Frey filaments and the hind limb use by the dynamic weight bearing device. Naloxone methiodide (NLXM) was used to test for the opioid receptor involvement. Knee cartilage destruction was assessed using contrast enhanced µCT.
Results: WBV reduced the OA-triggered mechanical sensitivity and restored the physiological hind limb use in both sexes. These analgesic effects were reversed by NLXM injected intraarticularly, on the spinal cord, or into the brain. µCT analysis revealed less cartilage damage in OA mice following WBV.
Conclusions: WBV alleviated mechanical pain and restored limb use via endogenous opioids, and attenuated cartilage destruction, offering new perspectives on OA treatment.
Research support: German Federal Ministry of Education and Research (BMBF; 1EC1408L).

WHOLE BODY VIBRATION IN EXPERIMENTAL OSTEOARTHRITIS IN MALES AND FEMALES - EFFECTS ON PAIN AND CARTILAGE DESTRUCTION