CAPACITIVE COUPLING ELECTRIC FIELDS IN THE TREATMENT OF VERTEBRAL COMPRESSION FRACTURES.

Positive effects of Capacitive Coupling Electric Field (CCEF) stimulation are described for several orthopedic indications such as the healing of recent fractures, non-unions and spinal fusion, due to the capacity to involve the up-regulation of osteopromotive factors. In vitro studies on MC3T3-E1 bone cells showed that CCEF acts opening the plasma membrane voltage gated calcium channels, thus increasing the cytosolic calcium concentration and the phospholipase A2 (PLA2) activity. Cytosolic calcium activates the calmodulin pathway, thus resulting in an up-regulated expression of osteogenic genes, such as transforming growth factor-β superfamily genes (TGF-β1, -β2 -β3, bone morphogenetic protein-2 and -4), fibroblast growth factor (FGF)-2, osteocalcin (BGP) and alkaline phosphatase (ALP). PLA2 acts increasing the synthesis of Prostaglandin E2 (PGE2), which promotes osteogenesis by raising the cellular L-ascorbic acid uptake through the membrane carrier sodium vitamin C transporter-2 (SVCT-2). In vivo, Brighton et al. in a castration-induced osteoporosis animal model, demonstrated that CCEF was able to restore bone mass/unit volume in the rat vertebral body. To investigate the role of CCEF stimulation in vertebral bone marrow edema (VBME) its percentage was assessed in 24 patients with 25 acute vertebral compression fractures (VCFs) conservatively treated with CCEF (group A) or without CCEF (group B) using serial MR imaging follow-up at 0, 30, 60, 90 days. Pain and quality of life were assessed by visual analog scale (VAS) and Oswestry Low Back Disability Index (ODI) in the same periods. At 90 day follow-up the complete resolution of VBME was found only in group A (p=0.0001). A significant improvement of VAS (p=0.007) and ODI (p=0.002) was also observed in group A. This preliminary observational study shows that patients treated with CCEF stimulation present an improvement of clinical symptoms with faster fracture healing and a complete VBME resolution.