Effects on posture by different neuromuscular afferent stimulations and proprioceptive insoles: Rasterstereographic evaluation

Background: Proprioceptive neuromuscular stimulating insoles are increasingly applied in treating functional complaints, chronic pain, foot disorders and so on. Objectives: To evaluate rasterstereography as a tool in objectifying postural changes resulting from neuromuscular afferent stimulation and proprioceptive neuromuscular stimulating insoles and to compare the respective effects on posture. Study design: This is a prospective experimental study. Methods: A total of 27 healthy volunteers were consecutively exposed to six different varying intense neuromuscular afferent stimulating test conditions at three different times. One test condition featured proprioceptive neuromuscular stimulating insoles. In each test condition, a sequence of 12 rasterstereographic recordings of back shape was documented. Changes between six different test conditions and over time for 14 posture characterising parameters were investigated, for example, trunk inclination, pelvic torsion, lateral deviation of the spine’s amplitude or sagittal spinal curve. Results: Standard deviation of our rasterstereographic measurements (±2.67 mm) was better than in most comparable reference values. Different neuromuscular stimuli were found to provoke significant changes to various posture parameters, including trunk inclination, pelvic torsion and so on ( each p < 0.001, F-tests). Proprioceptive neuromuscular stimulating insoles induced significant changes for parameter lateral deviation of the spine’s amplitude (p = 0.03). Conclusion: Neuromuscular afferent stimulation and proprioceptive neuromuscular stimulating insoles induce postural changes, which can be detected reliably by rasterstereography. Clinical relevance We demonstrated that rasterstereography – a radiation-free imaging modality – enables visualisation and documentation of subtle postural changes induced by varying intense neuromuscular afferent stimulation and the application of proprioceptive neuromuscular stimulating insoles