Evaluation of Low-Level Laser Therapy with a He–Ne Laser on the Healing of an Osteochondral Defect Using a Biomechanical Test

Photobiomodulation and mesenchymal stem cell-conditioned medium for the repair of experimental critical-size defects

Orthopedic surgeons face a significant challenge in treating critical-size femoral defects (CSFD) caused by osteoporosis (OP), trauma, infection, or bone tumor resections. In this study for the first time, the application of photobiomodulation (PBM) and bone marrow mesenchymal stem cell-conditioned medium (BM-MSC-CM) to improve the osteogenic characteristics of mineralized bone scaffold (MBS) in ovariectomy-induced osteoporotic (OVX) rats with a CSFD was tested. Five groups of OVX rats with CSFD were created: (1) Control (C); (2) MBS; (3) MBS + CM; (4) MBS + PBM; (5) MBS + CM + PBM. Computed tomography scans (CT scans), compression indentation tests, and histological and stereological analyses were carried out after euthanasia at 12 weeks following implantation surgery. The CT scan results showed that CSFD in the MBS + CM, MBS + PBM, and MBS + CM + PBM groups was significantly smaller compared to the control group (p = 0.01, p = 0.04, and p = 0.000, respectively). Moreover, the CSFD size was substantially smaller in the MBS + CM + PBM treatment group than in the MBS, MBS + CM, and MBS + PBM treatment groups (p = 0.004, p = 0.04, and p = 0.01, respectively). The MBS + PBM and MBS + CM + PBM treatments had significantly increased maximum force relative to the control group (p = 0.01 and p = 0.03, respectively). Bending stiffness significantly increased in MBS (p = 0.006), MBS + CM, MBS + PBM, and MBS + CM + PBM treatments (all p = 0.004) relative to the control group. All treatment groups had considerably higher new trabecular bone volume (NTBV) than the control group (all, p = 0.004). Combined therapies with MBS + PBM and MBS + CM + PBM substantially increased the NTBV relative to the MBS group (all, p = 0.004). The MBS + CM + PBM treatment had a markedly higher NTBV than the MBS + PBM (p = 0.006) and MBS + CM (p = 0.004) treatments. MBS + CM + PBM, MBS + PBM, and MBS + CM treatments significantly accelerated bone regeneration of CSFD in OVX rats. PBM + CM enhanced the osteogenesis of the MBS compared to other treatment groups.

Does low level laser therapy has effects on inflammatory biomarkers IL-1β, IL-6, TNF-α, and MMP-13 in osteoarthritis of rat models-a systemic review and meta-analysis

Osteoarthritis (OA) is a chronic degenerative joint disease and is considered as the most common cause of pain and disability. To the best of our knowledge, it is generally observed that there is a lack of evidence on the effects of low-level laser therapy (LLLT) on inflammatory cytokines in OA. The present review aims to appraise the current evidence of efffects of LLLT on inflammatory cytokines in OA of the knee. Medical databases such as Medline, PubMed, EMBASE, PEDro CINAHL, Web of Science, Cochrane register, and Google reference were searched from its inception to June 2019. Articles that meet the inclusion criteria: subjects (animals-Wistar rats) induced with OA; rats with age group of 50-90 days; weight of 150-300 g; finding the effects of LLLT; reporting inflammatory cytokines; and articles written in English were included. The reviewers assessed the methodological quality of the primary studies. Data of inflammatory cytokines IL-1β, IL-6, TNF-α, and MMP-13 were extracted for analysis. The Q (x2) test and I2 statistics analysis were performed to find the heterogeneity evaluation. Standard mean difference (SMD) and its 95% confidence interval (CI) were used to synthesize the data. Two hundred eleven potential articles were identified and 186 articles were excluded based on the selection criteria. The rest of the 25 articles were read and 8 articles were selected for further study. From the study, it is observed that the laser therapy group had mild to moderate improvement than control group in IL-1β, TNF-α, and MMP-13 (IL-1β; SMD 1.21 [95% CI - 0.278, 2.704], TNF-α; SMD 5.19 [95% CI 2.413, 7.961], and MMP-13 SMD - 1.45 [95% CI - 5.121, 2.211]), while IL-6 [SMD 3.11 (95% CI 0.662, 5.549] did not show any considerable improvement after laser therapy. The present review provides the evidence of LLLT-dependent reduction of IL-1β, TNF-α, and MMP-13, and its ability to modulate proliferation of inflammatory cells, which makes LLLT a suitable treatment for OA. Though the included studies showed a high heterogeneity in treatment parameter, the beneficial effect of LLLT on changes in inflammatory cytokines, such as IL-6, seems to be unaffected.

Photobiomodulation therapy in knee osteoarthritis reduces oxidative stress and inflammatory cytokines in rats

Knee osteoarthritis (OA) is a chronic disease that causes pain and gradual degeneration of the articular cartilage. In this study, MIA-induced OA knee model was used in rats to test the effects of the photobiomodulation therapy (PBM). We analyzed the inflammatory process (pain and cytokine levels), and its influence on the oxidative stress and antioxidant capacity. Knee OA was induced by monosodium iodoacetate (MIA) intra-articular injection (1.5 mg/50 μL) and the rats were treated with eight sessions of PBM 3 days/week (904 nm, 6 or 18 J/cm² ). For each animal, mechanical and cold hyperalgesia and spontaneous pain were evaluated; biological analyses were performed in blood serum, intra-articular lavage, knee structures, spinal cord and brainstem. Cytokine assays were performed in knee, spinal cord and brainstem samples. The effects of the 18 J/cm² dose of PBM were promising in reducing pain and neutrophil activity in knee samples, together with reducing oxidative stress damage in blood serum and spinal cord samples. PBM improved the antioxidant capacity in blood serum and brainstem, and decreased the knee pro-inflammatory cytokine levels. Our study demonstrated that PBM decreased oxidative damage, inflammation and pain. Therefore, this therapy could be an important tool in the treatment of knee OA.

Current Trends in the Evaluation of Osteochondral Lesion Treatments: Histology, Histomorphometry, and Biomechanics in Preclinical Models

Osteochondral lesions (OCs) are typically of traumatic origins but are also caused by degenerative conditions, in primis osteoarthritis (OA). On the other side, OC lesions themselves, getting worse over time, can lead to OA, indicating that chondral and OC defects represent a risk factor for the onset of the pathology. Many animal models have been set up for years for the study of OC regeneration, being successfully employed to test different treatment strategies, from biomaterials and cells to physical and biological adjuvant therapies. These studies rely on a plethora of post-explant investigations ranging from histological and histomorphometric analyses to biomechanical ones. The present review aims to analyze the methods employed for the evaluation of OC treatments in each animal model by screening literature data within the last 10 years. According to the selected research criteria performed in two databases, 60 works were included. Data revealed that lapine (50% of studies) and ovine (23% of studies) models are predominant, and knee joints are the most used anatomical locations for creating OC defects. Analyses are mostly conducted on paraffin-embedded samples in order to perform histological/histomorphometric analyses by applying semiquantitative scoring systems and on fresh samples in order to perform biomechanical investigations by indentation tests on articular cartilage. Instead, a great heterogeneity is pointed out in terms of OC defect dimensions and animal's age. The choice of experimental times is generally adequate for the animal models adopted, although few studies adopt very long experimental times. Improvements in data reporting and in standardization of protocols would be desirable for a better comparison of results and for ethical reasons related to appropriate and successful animal experimentation.

Comparison of effects of LLLT and LIPUS on fracture healing in animal models and patients: A systematic review

The aim of this paper is to study the in vivo potency of low-level laser therapy (LLLT) and low intensity pulsed ultrasound (LIPUS) alone, accompanied by bone grafts, or accompanied by other factors on fracture healing in animal models and patients. In this paper, we aim to systematically review the published scientific literature regarding the use of LLLT and LIPUS to accelerate fracture healing in animal models and patients. We searched the PubMed database for the terms LLLT or LIPUS and/or bone, and fracture. Our analysis also suggests that both LIPUS and LLLT may be beneficial to fracture healing in patients, and that LIPUS is more effective. These finding are of considerable importance in those treatments with a LIPUS, as a laser device may reduce healing time. The most clinically relevant impact of the LIPUS treatment could be a significant reduction in the proportion of patients who go on to develop a nonunion. If it is confirmed that the therapeutic influence is true and reliable, patients will obtain benefits from LIPUS and LLLT. Further clinical trials of high methodological quality are needed in order to determine the optimal role of LIPUS and LLLT in fracture healing in patients.

Effects of Bone Marrow Mesenchymal Stem Cells-Conditioned Medium on Tibial Partial Osteotomy Model of Fracture Healing in Hypothyroidism Rats

Background

Hypothyroidism is associated with dysfunction of the bone turnover with reduced osteoblastic bone formation and osteoclastic bone resorption. Mesenchyme stem cells (MSCs) secrete various factors and cytokines that may stimulate bone regeneration. The aim of this study was to determine the effects of MSCs-conditioned medium (CM) in hypothyroidism male rats after inducing bone defect.

Methods

: In this study, 24 male rats were randomly assigned to three groups: (I) hypothyroidism+bone defect (HYPO), (II) hypothyroidism+bone defect+CM (HYPO+CM), and (III) no hypothyroidism+bone defect (control). Four weeks after surgery, the right tibia was removed, and immediately, biomechanical and histological examinations were performed.

Results

The results showed a significant reduction in bending stiffness (32.64±3.99), maximum force (14.63±1.89), high stress load (7.59±2.31), and energy absorption (12.68±2.12) at the osteotomy site in hypothyroidism rats in comparison to the control and hypothyroidism+condition medium groups (P<0.05). There was also a significant decrease in the trabecular bone volume (3.86±3.88) and the number of osteocytes (5800±859.8) at the osteotomy site in hypothyroidism rats compared to the control and hypothyroidism+condition medium groups (P<0.01 and P<0.02, respectively).

Conclusion

The present study suggests that the use of the CM can improve the fracture regeneration and accelerates bone healing at the osteotomy site in hypothyroidism rats.

Radiological and biochemical effects (CTX-II, MMP-3, 8, and 13) of low-level laser therapy (LLLT) in chronic osteoarthritis in Al-Kharj, Saudi Arabia

Inflammation of synovial membrane and degeneration of articular cartilage in osteoarthritis (OA) lead to major changes in joint space width (JSW) and biochemical components such as collagen-II telopeptide (CTX-II) and matrix metallo protineases (MMP-3, 8, and 13). Low-level laser therapy (LLLT) is thought to have an analgesic effect as well as biomodulatory effect on microcirculation and cartilage regeneration in animal studies. The objective of this study was to examine the analgesic and biochemical effect of LLLT in patients with knee osteoarthritis. Subjects (n = 34) who fulfilled the selection criteria were randomly divided into active group (n = 17) and placebo group. Subjects in active group were irradiated laser with the frequency of 3 days per week for 4 weeks with the specific parameters on 8 different points on the joint at 1.5 J per point for 60 s for 8 points for a total dose of 12 J in a skin contact method. The placebo group was treated with the same probe with minimum emission of energy. Visual analog scale for pain intensity, joint space width, collagen-II telopeptide, and matrix metallo protinease-3, 8, and 13 was measured before treatment and at 4 and 8 weeks following treatment. Data are analyzed with mean values and standard deviation with p < 0.05. Baseline values of all outcome measures show insignificant difference (p > 0.05) in both groups which shows homogeneity. After 4- and 8-week treatment, active laser group shows more significant difference (p < 0.001) in all the parameters than the placebo laser group (p > 0.05). Our results show that low-level laser therapy was more efficient in reducing pain and improving cartilage thickness through biochemical changes.

LASER versus electromagnetic field in treatment of hemarthrosis in children with hemophilia

Children with hemophilia usually have recurrent joint bleeding that leads to joint damage, loss of range of motion, and restriction of mobility, therefore affecting the quality of life in these children. The purpose of this study was to compare the effects of low-level laser therapy (LLLT) to that of pulsed electromagnetic field (PEMF) in treatment of hemarthrosis in children with hemophilia. Thirty boys with hemophilia A with ages ranging from 9 to 13 years were selected and assigned randomly, using sealed envelopes, into two equal intervention groups. The study group I received the traditional physical therapy program in addition to LLLT, whereas the study group II received the same physical therapy program given to the study group I in addition to PEMF. Both groups received the treatment sessions three times per week for three successive months. Pain, laboratory investigations, swelling, and range of motion (ROM) of the affected knee joint, in addition to physical fitness were evaluated before, at the end of the sixth week and at 12 weeks of the treatment program. Laser group showed significant improvement in all measured variables after the sixth week of treatment when compared with PEMF. By 12 weeks of treatment, there was a significant improvement in pain, ROM, ESR and leucocytes levels in laser group compared with PEMF, while there was no significant difference in knee circumferences and the 6-min walk test (6MWT) between both groups. Both groups showed significant improvement at 12 weeks of treatment compared with that at 6 weeks. Both LLLT and PEMF are effective modalities in reducing pain, swelling, increasing ROM and improving physical fitness. Twelve weeks of treatment of both modalities demonstrated significant improvement than 6 weeks of treatment. Laser therapy induced significant improvement than electromagnetic therapy in treatment of hemarthrosis-related problems in children with hemophilia.

Effect of low-level laser therapy on the expression of inflammatory mediators and on neutrophils and macrophages in acute joint inflammation

INTRODUCTION

Inflammation of the synovial membrane plays an important role in the pathophysiology of osteoarthritis (OA). The synovial tissue of patients with initial OA is characterized by infiltration of mononuclear cells and production of proinflammatory cytokines and other mediators of joint injury. The objective was to evaluate the effect of low-level laser therapy (LLLT) operating at 50 mW and 100 mW on joint inflammation in rats induced by papain, through histopathological analysis, differential counts of inflammatory cells (macrophages and neutrophils), as well as gene expression of interleukin 1-beta and 6 (IL-1β and IL-6), and protein expression of tumor necrosis factor alpha (TNFα).

METHODS

Male Wistar rats (n = 60) were randomly divided into four groups of 15 animals, namely: a negative control group; an inflammation injury positive control group; a 50 mW LLLT group, subjected to injury and treated with 50 mW LLLT; and a 100 mW LLLT group, subjected to injury and treated with 100 mW LLLT. The animals were subject to joint inflammation (papain solution, 4%) and then treated with LLLT (808 nm, 4 J, 142.4 J/cm(2), spot size 0.028 for both groups). On the day of euthanasia, articular lavage was collected and immediately centrifuged; the supernatant was saved for analysis of expression of TNFα protein by enzyme-linked immunosorbent assay and expression of IL-1β and IL-6 mRNA by real-time polymerase chain reaction. A histologic examination of joint tissue was also performed. For the statistical analysis, analysis of variance with Tukey's post-hoc test was used for comparisons between each group. All data are expressed as mean values and standard deviation, with P < 0.05.

RESULTS

Laser treatment with 50 mW was more efficient than 100 mW in reducing cellular inflammation, and decreased the expression of IL-1β and IL-6. However, the 100 mW treatment led to a higher reduction of TNFα compared with the 50 mW treatment.

CONCLUSIONS

LLLT with 50 mW was more efficient in modulating inflammatory mediators (IL-1β, IL-6) and inflammatory cells (macrophages and neutrophils), which correlated with the histology that showed a reduction in the inflammatory process.