The effects of minimally invasive laser needle system on suppression of trabecular bone loss induced by skeletal unloading.

This study was aimed to evaluate the effects of low-level laser therapy (LLLT) in the treatment of trabecular bone loss induced by skeletal unloading. Twelve mice have taken denervation operation. At 2 weeks after denervation, LLLT (wavelength, 660 nm; energy, 3 J) was applied to the right tibiae of 6 mice (LASER) for 5 days/week over 2 weeks by using a minimally invasive laser needle system (MILNS) which consists of a 100 µm optical fiber in a fine needle (diameter, 130 µm) [corrected]. Structural parameters and histograms of bone mineralization density distribution (BMDD) were obtained before LLLT and at 2 weeks after LLLT. In addition, osteocyte, osteoblast, and osteoclast populations were counted. Two weeks after LLLT, bone volume fraction, trabeculae number, and trabeculae thickness were significantly increased and trabecular separations, trabecular bone pattern factor, and structure model index were significantly decreased in LASER than SHAM (p < 0.05). BMDD in LASER was maintained while that in SHAM was shifted to lower mineralization. Osteocyte and osteoblast populations were significantly increased but osteoclast population was significantly decreased in LASER when compared with those in SHAM (p < 0.05). The results indicate that LLLT with the MILNS may enhance bone quality and bone homeostasis associated with enhancement of bone formation and suppression of bone resorption.

Development of a minimally invasive laser needle system: effects on cortical bone of osteoporotic mice.

Many studies have shown the positive effects of low-level laser therapy in the treatment of bone disease. However, laser radiation is scattered in the skin surface which reduces the initial photon density for tissue penetration and consequently the therapeutic efficacy. We developed a minimally invasive laser needle system (MILNS) to avoid laser scattering in tissue and investigated its stimulatory effects in the cortical bone of osteoporotic mice. The MILNS was designed to stimulate cortical bone directly by employing fine hollow needles to guide 100 µm optical fibers. The study animals comprised 12 mice which were subjected to sciatic denervation of the right hind limb and were randomly divided into two groups, a sham group and a laser group which were treated using the MILNS for 2 weeks without and with laser irradiation, respectively. In vivo micro-CT images were taken to analyze the structural parameters and bone mineral density. After 2 weeks of treatment with the MILNS, the relative changes in mean polar moment inertia, cross-section thickness, and periosteal perimeter were significantly higher in the laser group than in the sham group. Moreover, the distribution of bone mineral density index was higher in the laser group. The MILNS was developed as a minimally invasive treatment modality for bone disease and resulted in positive therapeutic efficacy in the cortical bone of osteoporotic mice.

Investigation of electrical responses to acupuncture stimulation: the effect of electrical grounding and insulation conditions.

Acupuncture in Oriental medicine has been widely used as a core therapeutic method due to its minimal side-effects and therapeutic efficacy. However, the electrical response to acupuncture stimulation (ERAS) has not been clearly studied under acupuncture conditions that might affect the efficacy of acupuncture therapy. In this study, the ERAS was objectively investigated by measuring meridian electric potentials (MEPs) when the electrical grounding conditions of the operator and subject were varied, and when the insulation conditions of acupuncture needle were varied. MEPs between Sang-geoheo (ST37) and Ha-geoheo (ST39) of the Stomach Meridian (ST) were measured by stimulating Jok-samni (ST36) with an acupuncture needle. For non-insulated acupuncture stimulation (NIAS), the average MEP peak was 148.6 +/- 20.6 when neither the operator nor the subject were electrically grounded, 23.1 +/- 8.8 when the subject only was electrically grounded, 348 +/- 76.8 when the operator only was electrically grounded, and 19.9 +/- 4.7 when both the operator and the subject were electrically grounded. The MEPs presented various magnitudes and patterns depending on the electrical grounding conditions. The MEP pattern was very similar to that of the charge and discharge of a capacitor. For insulated acupuncture stimulation (IAS), the average MEP peak was 20 +/- 4 in all electrical grounding conditions, which is not a significant electric response for acupuncture stimulation. In terms of electricity, this study verified that acupuncture therapy might be affected by acupuncture conditions such as (1) the electrical grounding condition of the operator and the subject and (2) the insulation condition of the acupuncture needle.