The immediate effects of passive joint mobilisation on local muscle function. A systematic review of the literature

Background: Passive joint mobilisation is popular among healthcare providers and their patients; however, its effectiveness for improving muscle function is not well researched and the mechanisms of action involved are unclear. Objectives: To assess the effect of passive joint mobilisations on the function of muscles surrounding the targeted joints in symptomatic as well as asymptomatic individuals. Selection criteria: Controlled experimental trials assessing the immediate effect of passive joint mobilisation on outcomes associated with local muscle function. Data collection: Two authors independently assessed trial quality and extracted data. Main results: A total of seventeen studies were included, of which ten studies reported data on asymptomatic individuals and seven studies reported data on symptomatic individuals with various conditions. There is a moderate level of evidence that joint mobilisation immediately decreases the activation of superficial muscles during low load conditions in symptomatic individuals. For asymptomatic individuals, there is a low level of evidence that passive joint mobilisation improves maximum muscle strength when compared to sham mobilisation, opposed to a very low level of evidence suggesting no effect in symptomatic individuals. The five studies reporting data on both, changes in muscle function as well as changes in pain, suggest that other, not pain-related mechanisms may play an important role regarding the reported improvement in muscle function. Conclusion: Current best evidence suggests that passive joint mobilisation has the ability to immediately alter muscle function. The specific mechanisms of action involved require further basic science investigations. Registration number (PROSPERO): CRD42018117033.