Treatment of partial injury of the calcaneus tendon with heterologous fibrin biopolymer and/or photobiomodulation in rats.

The present study aimed to evaluate the new heterologous fibrin biopolymer associated, or not, with photobiomodulation therapy for application in tendon injuries, considered a serious and common orthopedic problem. Thus, 84 Rattus norvegicus had partial transection of the calcaneus tendon (PTCT) and were randomly divided into: control (CG); heterologous fibrin biopolymer (HFB); photobiomodulation (PBM); heterologous fibrin biopolymer + photobiomodulation (HFB + PBM). The animals received HFB immediately after PTCT, while PBM (660 nm, 40 mW, 0.23 J) started 24 h post injury and followed every 24 h for 7, 14, and 21 days. The results of the edema volume showed that after 24 h of PTCT, there was no statistical difference among the groups. After 7, 14, and 21 days, it was observed that the treatment groups were effective in reducing edema when compared to the control. The HFB had the highest edema volume reduction after 21 days of treatment. The treatment groups did not induce tissue necrosis or infections on the histopathological analysis. Tenocyte proliferation, granulation tissue, and collagen formation were observed in the PTCT area in the HFB and HFB + PBM groups, which culminated a better repair process when compared to the CG in the 3 experimental periods. Interestingly, the PBM group revealed, in histological analysis, major tendon injury after 7 days; however, in the periods of 14 and 21 days, the PBM had a better repair process compared to the CG. In the quantification of collagen, there was no statistical difference between the groups in the 3 experimental periods. The findings suggest that the HFB and PBM treatments, isolated or associated, were effective in reducing the volume of the edema, stimulating the repair process. However, the use of HFB alone was more effective in promoting the tendon repair process. Thus, the present study consolidates previous studies of tendon repair with this new HFB. Future clinical trials will be needed to validate this proposal.

Systematic Review of Photobiomodulation Therapy (PBMT) on the Experimental Calcaneal Tendon Injury in Rats.

This systematic review analyzed the light parameters and the effects of photobiomodulation therapy (PBMT) through low-level laser therapy (LLLT) and/or LED (light-emitting diode) on tendon repair of rats submitted to calcaneal injury. This study was conducted in accordance with the guidelines of the Preferred Reporting Items for Meta-Analysis, and PubMed and MEDLINE databases were accessed to search eligible studies published in English. The search terms were as follows: "Achilles tendon" or "Calcaneal tendon" or "tendon injuries" or "soft tissue injuries" and "tendinopathy" or "tendinitis" and "low-level light therapy" or "low-level laser therapy" or "low intensity power therapy" or "light-emitting diode" or photobiomodulation." The SYRCLE (SYstematic Review Center for Laboratory animal Experimentation) risks of bias was used to assess the risk of bias for selected studies. A total of 225 studies were found based on the descriptors used, and only 33 studies were eligible. Light parameters identified per point of irradiation were approximately 60 mW (continuous mode at infrared spectra), 2 W cm-2 , 2 J and 45 J cm-2 . Light parameters at red spectra, continuous versus pulsed mode, and PBMT combined or compared with other therapies such as ultrasound, and studies using unhealthy rats (ovariectomized and/or diabetic models) were also identified and grouped according to these similarities. The main effects found were decreased inflammatory markers and signs of inflammatory process. PBMT (laser/LED) has positive effects in reducing the inflammatory and time for tissue repair in animal models of tendon injury and/or tendinitis using parameters identified.

Effects of Low-Power Light Therapy on the Tissue Repair Process of Chronic Wounds in Diabetic Feet.

OBJECTIVE: To analyze the efficacy of the therapeutic use of Low-Level Laser Therapy (LLLT) on the tissue repair process of chronic wounds in patients with diabetic feet through the analysis of Pressure Ulcer Scale for Healing (PUSH) scales, pain and the measurement done using the ImageJ© software. METHODS: This clinical trial was carried out with 18 patients 30-59 years of age, who had chronic wounds on their foot due to complications of diabetes mellitus. The patients were randomly allocated in two different groups of equal numbers: Control and Laser Groups. The LLLT equipment used in the research has a wavelength of 660 nm, 30 mW power, continuous mode emission, 6 J/cm2 dosimetry, 48/48 h in a 4-week period. Measurement and the aspect of wounds were noted in the PUSH scale and the pain was evaluated weekly. The Mann-Whitney U nonparametric test was used to compare groups. RESULTS: The Laser Group presented a significant increase of the tissue repair index when compared with the Control Group, with a significant statistical difference (p < 0.013). There was no significant difference between the groups in all the weeks using the PUSH scale. CONCLUSIONS: The use of LLLT on chronic wounds in a diabetic foot demonstrated efficacy on the progression of the tissue repair process in a short period.

Evaluation of bone repair after application of a norbixin membrane scaffold with and without laser photobiomodulation (λ 780 nm).

Biocompatible membranes are widely used in medicine to stimulate bone repair. Several studies have demonstrated that laser photobiomodulation (PBM) also stimulates osteoblast proliferation and osteogenesis at the fracture site, leading to a greater deposition of bone mass and accelerating the process of bone consolidation. This work assessed the therapeutic effect of 780-nm laser PBM and a polystyrene membrane coated with norbixin and collagen (PSNC) on bone healing in rats with calvarial bone defect. Histological staining, Raman spectroscopy, and scanning electron microscopy (SEM) were used to evaluate the bone repair process. Four experimental treatment groups were compared: C, control; M, membrane only; L, laser PBM only; and ML, membrane + laser PBM. A bone defect was created in the calvaria of each animal, with each group subdivided into two subgroups that underwent euthanasia after 15 and 30 days treatment. The L and ML groups were irradiated (λ = 780 nm, ED = 6 J/cm2, P = 60 mW, t = 4 s) postoperatively on alternate days until they were euthanized. The bone concentration of hydroxyapatite (CHA) showed a clear gradation with increasing phosphate area in the order B (normal cortical bone) > L > M > ML > C for both periods. The PSNC membrane was effective in reducing the inflammatory process and served as a scaffold for bone repair. The laser PBM also showed positive effects on the bone repair process with increased deposition and organization of the newly formed bone. However, laser PBM failed to improve the bioactive properties of the membrane scaffold.

Low-intensity LED therapy (658 nm) on burn healing: a series of cases.

The objective of this study was to evaluate the effects of LED on burns healing. Five patients with skin burns were submitted to photobiomodulation by LED, GaAsIP diode, (λ 658 nm) with 40 mW, 7 J/cm2 on every other day. Biopsies of burned skin were performed and the healing process was photographed. Patients with bilateral burns were used as self-control, having one limb being irradiated and the contralateral limb irradiated with placebo. The burns treated with LED showed higher epithelization, with keratinocytes and fibroblasts proliferation, increased collagen synthesis, decreased pain, and pruritus. In conclusion, there was a faster clinical improvement in the irradiated limbs.

Low-intensity LED therapy (λ 640 ± 20 nm) on saphenectomy healing in patients who underwent coronary artery bypass graft: a randomized, double-blind study.

Myocardial revascularization surgery (CABG) is the most appropriate treatment for coronary artery disease. Currently, the great challenge is to reduce postoperative complications, such as wound infections, dehiscence, pain, and patients' quality of life. The saphenectomy is the target of complications in 10% of cases, which can cause greater morbidity, time, and cost of hospitalization. Studies show that low-intensity laser or light-emitted diode (LED) therapy promotes positive biomodulation of the tissue repair process, culminating in a lower incidence of dehiscence, pain reduction, and improvement in quality of life. The objective of the present study was to evaluate clinically the saphenous tissue repair after LED therapy. Forty subjects of both genders who underwent CABG with extracorporeal circulation were randomly divided into two groups: the placebo (PG) and experimental (EG). The experimental group underwent low-intensity LED therapy (λ 640 ± 20 nm, 6 J/cm2) on saphenectomy. The tissue repair was analyzed by digital photogrammetry on the first and fifth postoperative day. The border closure was blindly evaluated by three researchers. The hematoma and hyperemia area was quantitatively analyzed using ImageJ© software. The results showed that in the experimental group, there were less bleeding points and no dehiscence in saphenectomy, as compared to the placebo group. There was also a smaller area of hematoma and hyperemia in the experimental group (p < 0.0009). These data lead to the conclusion that the type of phototherapy protocol employed can assist in tissue repair.

Low-intensity laser (660 NM) has analgesic effects on sternotomy of patients who underwent coronary artery bypass grafts.

BACKGROUND: The aim of this study was to evaluate the efficacy of low-level laser therapy for reducing the acute pain of sternotomy in patients who underwent a coronary artery bypass graft (CABG). METHODS: This study was conducted with ninety volunteers who electively submitted to CABG. The volunteers were randomly allocated into three groups of equal size (n = 30): control, placebo, and laser (λ of 660 nm and spatial average energy fluency of 1.06 J/cm 2 ). Pain when coughing was assessed by a visual analog scale (VAS) and McGill Pain Questionnaire, according to sensory, affective, evaluative, and miscellaneous domains. The patients were followed for 1 month after the surgery. RESULTS: The laser group had a greater decrease in pain with analogous results, as indicated by both the VAS and the McGill questionnaire (P ≤ 0.05) on sensory and affective scores, on days 6 and 8 postsurgery compared to the placebo and control groups. CONCLUSION: Laser seems to be effective promoting pain reduction after coronary-arterial bypass grafting.

Photobiomodulation (Laser and LED) on Sternotomy Healing in Hyperglycemic and Normoglycemic Patients Who Underwent Coronary Bypass Surgery with Internal Mammary Artery Grafts: A Randomized, Double-Blind Study with Follow-Up.

BACKGROUND AND OBJECTIVE: This study aimed at analyzing the healing effects of low-level laser therapy (LLLT) (λ620 nm, 6 J/cm2) and light-emitting diode (LED) therapy (λ640 nm, 6 J/cm2) on the longitudinal sternotomy incisions of hyperglycemic and normoglycemic patients who underwent coronary artery bypass grafting (CABG). MATERIALS AND METHODS: 120 volunteers were electively submitted to CABG and were randomly allocated into four different groups of equal size (n = 30): control, placebo, laser (λ of 640 nm and spatial average energy fluency [SAEF] of 1.06 J/cm2), and LED (λ of 660 ± 20 nm and SAEF of 0.24 J/cm2). Laser and LED groups were irradiated from the second to eighth day postsurgery, and sternotomy incision was photographically registered. Then, participants were also separated into hyperglycemic and normoglycemic groups, according to their fasting blood glucose test before surgery. Three researchers blindly analyzed the incision photographs to determine hyperemia and wound closure at the first day of hospital discharge (eighth postoperative day). RESULTS: LLLT and LED groups had similarly less hyperemia and less incision bleeding or dehiscence (p ≤ 0.005) and the outcomes were also analogous between hyperglycemic and normoglycemic patients, which indicates no difference observed in an intragroup analysis (p ≥ 0.05). CONCLUSIONS: With the present therapy parameters, it may be assumed that both coherent light (laser) and non-coherent light (LED) are effective in promoting sternotomy and healing acceleration, which are evident on the eighth day postsurgery.

Low-intensity laser (660 nm) on sternotomy healing in patients who underwent coronary artery bypass graft: a randomized, double-blind study.

The aim of this study was to analyze the healing effects of low-level laser therapy (LLLT) on the longitudinal sternotomy incisions of patients who underwent coronary artery bypass graft (CABG). The volunteers were randomized into three groups of equal size (n = 30): control, placebo, and laser (λ = 660 nm and spatial average energy fluency [SAEF] = 1.06 J/cm2). The patients in the laser group underwent irradiation on postoperative days 2, 4, 6, and 8, and their sternotomy incisions were photographed immediately after the surgery and 8 days later for analysis. Three researchers who were blinded to the patient treatment groups analyzed the incision photographs to assess hyperemia and wound closure on the day of hospital discharge (eighth postoperative day). The sternotomy incisions in the LLLT group demonstrated less hyperemia, incisional bleeding, and dehiscence (p ≤ 0.005).

Low-Level Laser and Light-Emitting Diode Therapy for Pain Control in Hyperglycemic and Normoglycemic Patients Who Underwent Coronary Bypass Surgery with Internal Mammary Artery Grafts: A Randomized, Double-Blind Study with Follow-Up.

OBJECTIVE: This study aimed to evaluate the efficacy of low-level laser therapy (LLLT) and light-emitting diodes (LEDs) for reducing pain in hyperglycemic and normoglycemic patients who underwent coronary artery bypass surgery with internal mammary artery grafts. METHODS: This study was conducted on 120 volunteers who underwent elective coronary artery bypass graft (CABG) surgery. The volunteers were randomly allocated to four different groups of equal size (n = 30): control, placebo, LLLT [λ = 640 nm and spatial average energy fluence (SAEF) = 1.06 J/cm(2)], and LED (λ = 660 ± 20 nm and SAEF = 0.24 J/cm(2)). Participants were also divided into hyperglycemic and normoglycemic subgroups, according to their fasting blood glucose test result before surgery. The outcome assessed was pain during coughing by a visual analog scale (VAS) and the McGill Pain Questionnaire. RESULTS: The patients were followed for 1 month after the surgery. The LLLT and LED groups showed a greater decrease in pain, with similar results, as indicated by both the VAS and the McGill questionnaire (p ≤ 0.05), on the 6th and 8th postoperative day compared with the placebo and control groups. The outcomes were also similar between hyperglycemic and normoglycemic patients. One month after the surgery, almost no individual reported pain during coughing. CONCLUSIONS: LLLT and LED had similar analgesic effects in hyperglycemic and normoglycemic patients, better than placebo and control groups.