Ankle joint mobilization reduces axonotmesis-induced neuropathic pain and glial activation in the spinal cord and enhances nerve regeneration in rats

Abstract

An important issue in physical rehabilitation is how to protect from or to reduce the effects of peripheral nerve injury. In the present study, we examined whether ankle joint mobilization (AJM) would reduce neuropathic pain and enhance motor functional recovery after nerve injury. In the axonotmesis model, AJM during 15 sessions every other day was conducted in rats. Mechanical and thermal hyperalgesia and motor performance deficit were measured for 5 weeks. After 5 weeks, we performed morphological analysis and quantified the immunoreactivity for CD11b/c and glial fibrillary acidic protein (GFAP), markers of glial activation, in the lumbar spinal cord. Mechanical and thermal hyperalgesia and motor performance deficit were found in the Crush+Anesthesia (Anes) group (P<0.001), which was significantly decreased after AJM (P<0.001). In the morphological analysis, the Crush+Anes group presented reduced myelin sheath thickness (P<0.05), but the AJM group presented enhanced myelin sheath thickness (P<0.05). Peripheral nerve injury increased the immunoreactivity for CD11b/c and GFAP in the spinal cord (P<0.05), and AJM markedly reduced CD11b/c and GFAP immunoreactivity (P<0.01). These results show that AJM in rats produces an antihyperalgesic effect and peripheral nerve regeneration through the inhibition of glial activation in the dorsal horn of the spinal cord. These findings suggest new approaches for physical rehabilitation to protect from or reduce the effects of nerve injury.

Spinal Cord Stimulation Reduces Mechanical Hyperalgesia and Glial Cell Activation in Animals with Neuropathic Pain

“…Similarly, other therapeutic treatments that use our endogenous analgesia system also reduce glial activation including electroacupunture, peripheral nerve stimulation, or joint mobilization [16,25,35,69]. SCS increases release of the inhibitory neurotransmitters GABA, serotonin, and opioids in the spinal dorsal horn [7,8,30,39,32,59,65,67-58] that could directly inhibit activation of glial cells.…”

Neural Mobilization Reverses Behavioral and Cellular Changes That Characterize Neuropathic Pain in Rats

“…In addition, studies demonstrated that from inhalation anesthetics, halothane was able to decrease nociceptive reactions (returned to basal levels) faster than other inhalatory anesthesics (enflurane, isoflurane, and desflurane) [29]. Furthermore, studies have shown that the use of inhalational anesthetic during nine sessions of physical therapy in rats did not change expression of glial cells markers [4]. Suggesting that this anesthetic does not influence in chronic models of sensitization [30,31].…”

Neural Mobilization Treatment Decreases Glial Cells and Brain-Derived Neurotrophic Factor Expression in the Central Nervous System in Rats with Neuropathic Pain Induced by CCI in Rats

“…The technique aims to restore the mobility and elasticity of the peripheral nervous system that are lost due to strains that are imposed on the nerve trunks, roots, nerves, spinal cord, nerve wrappings, and the meninges by oscillations and joint angles. The growth of various physiotherapy techniques involving manual therapy that have been studied by researchers (e.g., global postural reeducation [18], joint mobilization [19–21], and the NM technique) has gradually resulted in the reaping of the fruits of new knowledge [22–24]. …”