Use Of Low-intensity Pulsed Ultrasound Research Articles

THE INFLUENCE OF L OW INTENSITY BROADBAND ULTRASOUND ON SKIN REGENETATION IN AN EXPERIMENT

THE INFLUENCE OF L OW INTENSITY BROADBAND ULTRASOUND ON SKIN REGENETATION IN AN EXPERIMENT

Daily low-intensity pulsed ultrasound stimulation mitigates joint degradation and pain in a post-traumatic osteoarthritis rat model

ObjectivesThe aim of this study was to investigate the effects of low-intensity pulsed ultrasound (LIPUS) in a post-traumatic osteoarthritis (OA) rat model and in vitro. MethodsThirty-eight male, four-month-old Sprague Dawley rats were randomly assigned to Sham, Sham ​+ ​US, OA, and OA ​+ ​US. Sham surgery was performed to serve as a negative control, and anterior cruciate ligament transection was used to induce OA. Three days after the surgical procedures, Sham ​+ ​US and OA ​+ ​US animals received daily LIPUS treatment, while the rest of the groups received sham ultrasound (US) signals. Behavioral pain tests were performed at baseline and every week thereafter. After 31 days, the tissues were collected, and histological analyses were performed on knees and innervated dorsal root ganglia (DRG) neurons traced by retrograde labeling. Furthermore, to assess the activation of osteoclasts by LIPUS treatment, RAW264.7 ​cells were differentiated into osteoclasts and treated with LIPUS. ResultsJoint degradation in cartilage and bone microarchitecture were mitigated in OA ​+ ​US compared to OA. OA ​+ ​US showed improvements in behavioral pain tests. A significant increase of large soma-sized DRG neurons was located in OA compared to Sham. In addition, a greater percentage of large soma-sized innervated neurons were calcitonin gene-related peptide-positive. Daily LIPUS treatment suppressed osteoclastogenesis in vitro, which was confirmed via histological analyses and mRNA expression. Finally, lower expression of netrin-1, a sensory innervation-related protein, was found in the LIPUS treated cells. ConclusionOur findings demonstrate that early intervention using LIPUS treatment has protective effects from the progression of knee OA, including reduced tissue degradation, mitigated pain characteristics, improved subchondral bone microarchitecture, and less sensory innervation. Furthermore, daily LIPUS treatment has a suppressive effect on osteoclastogenesis, which may be linked to the suppression of sensory innervation in OA. The translational potential of this articleThis study presents a new potential for early intervention in treating OA symptoms through the use of LIPUS, which involves the suppression of osteoclastogenesis and the alteration of DRG profiles. This intervention aims to delay joint degradation and reduce pain.

Evaluation of Low-Intensity Pulsed Ultrasound on Stress Fractures to Reduce the Time to Return to Sport or Activity in the Physically Active Population: A Systematic Review.

Stress fractures are a common and significant source of pain and burden that can require long periods of rest from physical activity to allow adequate healing. Specifically in athletes or those with physically demanding occupations, the prolonged period of rest and the potential for requiring surgical intervention in the case of poor or delayed healing can have devastating impacts on these individuals' careers and socioeconomic well-being. In this population, successful healing, in addition to a quicker healing time and a sooner return to activity, are important outcomes when faced with treating stress fractures. The use of low-intensity pulsed ultrasound (LIPUS) to accelerate bone healing has been a topic of investigation, though little research has explored the use of LIPUS specifically in the physically active population. The purpose of this study was to review the existing literature on the use of LIPUS for stress fracture healing in the physically active population with the outcome of a quicker return to sport or physical duties. The PubMed and Embase databases were screened for relevant articles using defined Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) criteria. Two independent researchers screened articles using PICOS criteria for inclusion in the review. Data were independently extracted regarding study and population characteristics as well as outcome measures, including time to healing of fractures and time to return to sport or physical activity. Five studies were ultimately included in the systematic review. One study investigated the use of LIPUS in pediatric athletes with spondylolysis, while four studies investigated lower extremity stress fractures in adult populations. All reported the outcomes of either rate or time to healing and ability to return to sport or activity. One study found a statistically significant improvement in the rate of bone union in the intervention group undergoing LIPUS compared to the control. Two studies found a statistically significant decrease in the time to resolution of symptoms, allowing an earlier return to sport or physical duties. Two studies found no difference in the time to healing or success rate of healing between the LIPUS group and the control group. This review of the literature suggests that the use of LIPUS for the treatment of stress fractures in the athletic or physically active population has the potential to expedite the resolution of symptoms and return to activity. Due to the heterogeneity of the existing studies, more research is needed to definitively determine the most appropriate clinical application of LIPUS and its most effective ultrasound settings. Further research should be directed toward more controlled studies specifically investigating the athletic and physically active population.

Multicenter consensus statements on the use of low-intensity pulsed ultrasound (LIPUS) in Hand Surgery.

The purpose of this agreement was to establish consensus statements on the use of low-intensity pulsed ultrasound (LIPUS) in hand surgery. Based on Delphi consensus methodology, a preliminary list of questions on the use of LIPUS in hand surgery was developed by an interdisciplinary team of hand and plastic surgeons as well as psychologists and experts from communications science. Based on these, questionnaires were invented and a total of three Delphi rounds have been conducted. Delphi panelists consisted of 11 German hand surgeons with a mean experience in hand surgery of 15years (7-23years). Questions and statements were revised during this process, resulting in a consensus at the end of round three. After three Delphi rounds, the following recommendations could be derived. LIPUS can be applied for impaired fracture healing of the digits, metacarpals, carpal bones as well as a prophylactic procedure in order to avoid further revision surgery. LIPUS therapy can be useful in addition to revision surgery for delayed union and non-unions. In the case of certain risk factors (replantation, revascularization, osteoporosis, smoking), it can be applied directly postoperatively in order to prevent impaired fracture healing. It should be applied for 90-120days. There is a consensus among German hand surgeons, when and how LIPUS can be applied for improving fracture healing of the hand. Randomized controlled trials with direct comparison of fracture treatment with and without LIPUS are needed to support these statements with objective data.

Influence of Low-Intensity Pulsed Ultrasound Parameters on the Bone Mineral Density in Rat Model: A Systematic Review.

Bone recovery typically depends on the age of organisms or the prevalence of metabolic disorders such as osteoporosis, which is a metabolic condition characterized by decreased bone strength and bone mineral density (BMD). Therefore, low-intensity pulsed ultrasound (LIPUS), a non-invasive method for osteogenic stimulation, presents promising results. However, heterogeneity in animal study designs is a typical characteristic. Hence, we conducted a systematic review to evaluate the effectiveness of LIPUS in the recovery of experimental bone defects using rat models. We examined the areal and volumetric BMD to identify LIPUS doses to be applied and evaluated the accuracy reported by previous studies. The Virtual Health Library regional portal, PubMed, Embase, EBSCOhost, Scopus and CAPES were reviewed for animal studies that compared fracture treatments based on LIPUS with sham or no treatments using rat models and reported BMD as an outcome. The tool provided by the Systematic Review Centre for Laboratory Animal Experimentation (SYRCLE) and the Collaborative Approach to Meta-Analysis and Review of Animal Data from Experimental Studies (CAMARADES) checklist were used to assess the bias and quality of such studies. Of the six studies reviewed, the most frequently used LIPUS dose had an ultrasonic frequency of 1.0MHz, repetition rate of 0.1kHz and pulse duration of 2000μs. An intensity (ISATA) of 30mW/cm2 was the most preferred for bone recovery. However, the BMD could not solely irrefutably evaluate the effectiveness of LIPUS in bone recovery as the results were discordant with each other. The discrepancies in experimental methodologies, low-quality classifications and high risk of bias in the selected studies, however, did not validate the undertaking of a meta-analysis. On the basis of the BMD results, no sufficient evidence was found to recommend the use of LIPUS for bone recovery in rat models. Thus, this systematic review indicates that the accuracy of such reports must be improved to improve their scientific quality to facilitate a transition of LIPUS applications from pre-clinical research to clinic use.

The safety and utility of low-intensity pulsed ultrasound for effective blood–brain barrier penetration in the treatment of glioblastoma: a scoping review protocol

Abstract Glioblastoma (GBM) is one of the most aggressive central nervous system tumours with suboptimal treatment options and associated poor prognosis. A major impediment to systemic treatment is the limitation of drug delivery to the tumour by the blood-brain barrier (BBB). Several novel techniques to permeate the BBB have been described, however of significant promise is the disruption of the blood brain barrier with low-intensity pulsed ultrasound (LIPU) to facilitate the delivery of varying therapeutic agents. This emerging technique has been demonstrated in clinical studies to enhance delivery of chemotherapeutic agents to the tumour. This study protocol seeks to guide the comprehensive review of literature concerning the safety and utility of LIPU for effective BBB penetration in the treatment of GBM. This protocol follows the Preferred Reporting Items for Systematic Reviews and Meta-Analysis Extension for Scoping Reviews (PRISMA ScR) guideline 2020. The search strategy was performed on four databases: PubMed, EMBASE, SCOPUS, and Cochrane Central Register of Controlled Trials. All observational and human randomised controlled studies describing the use of LIPU in the treatment of GBM will be included. Excluded studies include non-human randomized control trials, abstract only articles, letters to the editor, conference proceedings. Our outcomes include frequency of LIPU used, duration of intervention, clinical outcomes, complications, and challenges associated with the use of LIPU. This study aims to assess the safety and feasibility of this technique in the management of the GBM and proscribe its use if found effective to improve the outcomes in these patients.

Osteogenic effect of low-intensity pulsed ultrasound on peri-implant bone: A systematic review and meta-analysis.

Purpose This study aimed to evaluate the effect of low-intensity pulsed ultrasound (LIPUS) on promoting osseointegration around dental implants.Study selection A comprehensive search was performed on two databases, including MEDLINE (PubMed) and Web of Science to identify relevant studies published before June 1, 2022. Randomized controlled trials that met the inclusion criteria were selected for the study. The year of publication, study design, animal species, number of animals, number of implants, implant position, implant size, intervention, follow-up time, bone volume ratio (BV/TV), bone-implant contact ratio (BIC), and implant removal torque value (RTV) measurements, including mean and SD, were extracted.Results Ten randomized trials were included in this meta-analysis. The results showed that LIPUS significantly promoted osteogenesis around dental implants. Furthermore, in animal models of pre-existing diseases such as osteoporosis and diabetes, LIPUS had the same effect. The included data were divided into subgroups to explore the effects of different follow-up time, acoustic intensities, and frequencies. Results showed that higher acoustic intensities and frequencies significantly improve the osteogenic effects of LIPUS. There was some degree of heterogeneity owing to bias in the included studies. More high-quality randomized controlled trials are necessary in the future.Conclusions LIPUS can promote bone healing around dental implants and is an attractive option for edentulous patients, especially those with pre-existing diseases. Further clinical trials on the use of LIPUS in implant dentistry are warranted. Furthermore, future studies must pay more attention to acoustic intensity and frequency.

LIPUS accelerates bone regeneration via HDAC6-mediated ciliogenesis

Delayed fracture union and nonunion are common complications of fracture encountered, while Low-intensity pulsed ultrasound (LIPUS) can stimulate bone regeneration. Still, the underlying mechanism of LIPUS on bone regeneration has been poorly understood, which resulted in varied outcomes in the clinic. Therefore, figuring out the mechanism of LIPUS on bone regeneration can lay the foundation for better use of LIPUS in clinical bone regenerative therapies. In this study, we created transgenic mice to reveal the relationship between the periosteal cells' fate and the number of ciliated cells under the LIPUS stimulation. In vitro, we isolated the periosteal cell and aim to figure out the relationship between LIPUS and HDAC6-mediated ciliogenesis and find out a potential target for LIPUS-based bone regeneration strategies. The results showed that LIPUS promoted femoral bone defect regeneration and enhanced osteogenic differentiation of Prrx1+ cells. However, these pro-effects were significantly weakened when the Prrx1+ cell's primary cilia were knocked down. Besides, LIPUS stimulated the formation of Prrx1+ cells' primary cilia in the bone defect microenvironment. In vitro, the results supported that LIPUS enhanced the osteogenic differentiation of Prrx1+ cells through HDAC6-mediated ciliogenesis. In conclusion, λ LIPUS could promote the osteogenic differentiation of Prrx1+ cells to stimulate bone regeneration and inhibit the expression of HDAC6 to increase the prevalence of primary cilia in Prrx1+ cells. LIPUS could enhance the osteogenic differentiation of Prrx1+ cells mainly through HDAC6-mediated ciliogenesis.

Low-intensity pulsed ultrasound does not promote bone healing and functional recovery after open wedge high tibial osteotomy.

To evaluate whether low-intensity pulsed ultrasound (LIPUS) accelerates bone healing at osteotomy sites and promotes functional recovery after open-wedge high tibial osteotomy (OWHTO). Overall, 90 patients who underwent OWHTO without bone grafting were enrolled in this nonrandomized retrospective study, and 45 patients treated with LIPUS were compared with 45 patients without LIPUS treatment in terms of bone healing and functional recovery postoperatively. Clinical evaluations, including the pain visual analogue scale (VAS) and Japanese Orthopaedic Association (JOA) score, were performed preoperatively as well as six weeks and three, six, and 12 months postoperatively. The progression rate of gap filling was evaluated using anteroposterior radiographs at six weeks and three, six, and 12 months postoperatively. The pain VAS and JOA scores significantly improved after OWHTO in both groups. Although the LIPUS group had better pain scores at six weeks and three months postoperatively, there were no significant differences in JOA score between the groups. The lateral hinge united at six weeks postoperatively in 34 (75.6%) knees in the control group and in 33 (73.3%) knees in the LIPUS group. The progression rates of gap filling in the LIPUS group were 8.0%, 15.0%, 27.2%, and 46.0% at six weeks and three, six, and 12 months postoperatively, respectively, whereas in the control group at the same time points they were 7.7%, 15.2%, 26.3%, and 44.0%, respectively. There were no significant differences in the progression rate of gap filling between the groups. The present study demonstrated that LIPUS did not promote bone healing and functional recovery after OWHTO with a locking plate. The routine use of LIPUS after OWHTO was not recommended from the results of our study. Cite this article: Bone Jt Open2022;3(11):885-893.

Effectiveness and Mechanisms of Low-Intensity Pulsed Ultrasound on Osseointegration of Dental Implants and Biological Functions of Bone Marrow Mesenchymal Stem Cells.

Dental implant restoration is the preferred choice for patients with dentition defects or edentulous patients, and obtaining stable osseointegration is the determining factor for successful implant healing. The risk of implant failure during the healing stage is still an urgent problem in clinical practice due to differences in bone quality at different implant sites and the impact of some systemic diseases on bone tissue metabolism. Low-intensity pulsed ultrasound (LIPUS) is a noninvasive physical intervention method widely recognized in the treatment of bone fracture and joint damage repair. Moreover, many studies indicated that LIPUS could effectively promote the osseointegration of dental implants and improve the osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs). This review is aimed at investigating the research progress on the use of LIPUS in dental implant medicine from three aspects: (1) discuss the promoting effects of LIPUS on osseointegration and peri-implant bone regeneration, (2) summarize the effects and associated mechanisms of LIPUS on the biological functions of BMSCs, and (3) introduce the application and prospects of LIPUS in the clinical work of dental implantation. Although many challenges need to be overcome in the future, LIPUS is bound to be an efficient and convenient therapeutic method to improve the dental implantation success rate and expand clinical implant indications.

The perceptions of clinicians using low-intensity pulsed ultrasound (LIPUS) for orthopaedic pathology: A national qualitative study

IntroductionLow-intensity pulsed ultrasound (LIPUS) is a non-invasive treatment modality for delayed union or non-union of acute fractures. We aimed to assess the current use of LIPUS at a national level in the United Kingdom, why and how clinicians use it, what treatment protocols are followed, and what the current perceptions are on this technology. MethodologyUsing a detailed online survey compromised of 20 questions delivered to known LIPUS users, we were able to collect qualitative data on indication of use, type of machine used, personal views on the technology, frequency of usage, and treatment protocols. Each question was peer-reviewed to exclude bias. ResultsA total of 70 respondents completed the survey. LIPUS was used by most clinicians for cases of non-union (N = 55, 78.5%) and delayed union (N = 51, 72.8%). The majority of respondents personally used a LIPUS device between 1 and 5 times in 12 months (N = 38, 54.3%). Most considered LIPUS a failure after three to six months of treatment without clinical improvement (N = 39, 55.7%). A total of 32 respondents (45.7%) mentioned the need for funding approval before accessing LIPUS technology. Poor revision surgery candidates (N = 48, 68.6%) and atrophic non-union (N = 46, 65.7%) were the most frequently cited reasons for using LIPUS technology as treatment. Most participants (N = 48, 68.6%) considered LIPUS to be cost-effective. Despite most clinicians being comfortable with the use of LIPUS, some respondents did not understand the basic science underpinning the technology nor could explain the need for LIPUS to patients comfortably. ConclusionLIPUS technology may have a significant role to play in the treatment of orthopaedic fracture related pathology. Regular users perceived the technology to be cost-effective and efficacious. Further research should standardize treatment protocols and aim to establish a national LIPUS registry

Effect of Low-Intensity Pulsed Ultrasound (LIPUS) on Alveolar Bone during Maxillary Expansion Using Clear Aligners.

The present study evaluated the possible effect of low-intensity pulsed ultrasound (LIPUS) on buccal bone plate thickness and height after maxillary arch expansion using clear aligners. The cone beam computed tomography (CBCT) of before and immediately after maxillary arch expansion (3 mm per side) of 28 adult patients (18 in LIPUS group and 10 in control) (average age 36.2 ± 13.2 years old) was analyzed. The wearing protocol of clear aligners in the LIPUS group was to change the aligners every 4 to 5 days, while the wearing protocol in the control group (without LIPUS) was to change the aligners every 7 to 10 days. Bone thickness at 3 mm and 6 mm from the buccal alveolar bone crests, along with the measurements of buccal alveolar bone heights, was measured in standardized sagittal sections. Data were analyzed through paired sample t-test and the Wilcoxon test. The results were given as mean ± standard deviation and 95% confidence intervals. p value < 0.05 was considered statistically significant. The results showed significant increase in bone height in both groups. However, comparison of both LIPUS and control groups showed no statistically significant difference in bone thickness or bone height. The results of this study showed that the use of LIPUS together with accelerated aligner tray change protocol did not affect alveolar bone integrity when compared to the control group.

Can low-intensity pulsed ultrasound (LIPUS) accelerate bone healing after intramedullary screw fixation for proximal fifth metatarsal stress fractures? A retrospective study

BackgroundIntramedullary screw fixation is considered the standard treatment for proximal fifth metatarsal stress fractures. Low-intensity pulsed ultrasound (LIPUS) is a well-known bone-healing enhancement device. However, to the best of our knowledge, no clinical study has focused on the effect of LIPUS for postoperative bone union in proximal fifth metatarsal stress fractures. This study aimed to investigate the effect of LIPUS treatment after intramedullary screw fixation for proximal fifth metatarsal stress fractures.MethodsBetween January 2015 and March 2020, patients who underwent intramedullary screw fixation for proximal fifth metatarsal stress fractures were investigated retrospectively. All patients underwent intramedullary screw fixation using a headless compression screw with autologous bone grafts from the base of the fifth metatarsal. The time to restart running and return to sports, as well as that for radiographic bone union, were compared between groups with or without LIPUS treatment. LIPUS treatment was initiated within 3 weeks of surgery in all cases.ResultsOf the 101 ft analyzed, 57 ft were assigned to the LIPUS treatment group, and 44 ft were assigned to the non-LIPUS treatment group. The mean time to restart running and return to sports was 6.8 and 13.7 weeks in the LIPUS treatment group and was 6.2 and 13.2 weeks in the non-LIPUS treatment group, respectively. There were no significant differences in these parameters between groups. In addition, the mean time to radiographic bone union was not significantly different between the LIPUS treatment group (11.9 weeks) and the non-LIPUS treatment group (12.0 weeks). The rate of postoperative nonunion in the LIPUS treatment group was 0% (0/57), while that in the non-LIPUS treatment group was 4.5% (2/44). However, this difference was not statistically significant.ConclusionsThere were no statistically significant differences regarding the time to start running, return to sports, and radiographic bone union in patients with or without LIPUS treatment after intramedullary screw fixation for proximal fifth metatarsal stress fractures. Therefore, we cannot recommend the routine use of LIPUS to shorten the time to bone union after intramedullary screw fixation for proximal fifth metatarsal stress fractures.

Impact of photobiomodulation and low-intensity pulsed ultrasound adjunctive interventions on orthodontic treatment duration during clear aligner therapy.

To assess the efficiency of low-intensity pulsed ultrasound (LIPUS) and photobiomodulation (PBM) interventions in accelerating orthodontic tooth movement during clear aligner therapy (CAT). This retrospective study was carried out on the records of 84 subjects who were treated using CAT. Twenty-eight patients were treated using CAT with a daily use of LIPUS for 20 minutes, 28 patients were treated using CAT with a daily use of PBM for 10 minutes, and 28 patients were treated using CAT alone. The total duration of treatment was recorded for all patients. One-way analysis of variance and post hoc Tukey test were used to assess whether there was any significant difference in total treatment duration among the three groups (P < .05). The mean treatment durations in days were 719 ± 220, 533 ± 242, and 528 ± 323 for the control, LIPUS, and PBM groups, respectively. The LIPUS group showed a 26% reduction, on average, in treatment duration when compared with the control group, whereas the PBM group showed an average 26.6% reduction in the treatment duration when compared with the control group. The results showed that there were statistically significant differences among the groups (P = .011). Treatment durations were significantly reduced in the LIPUS and PBM groups as compared with the control (P = .027 and P = .023, respectively), with no statistically significant differences between the LIPUS and PBM groups (P = .998). Daily use of LIPUS or PBM as adjunctive interventions during CAT could reduce the duration of orthodontic treatment.

The use of low intensity pulsed ultrasound in the foot and ankle.

Low intensity pulsed ultrasound (LIPUS) therapy has demonstrated clinical effectiveness in achieving union in a variety of fracture situations.Few studies have investigated the effectiveness of LIPUS therapy in foot and ankle surgery.The overall rate of union in all published studies relating to the use of LIPUS in a variety of foot and ankle fracture and fusion situations is 95%.Some studies suggest lower healing rates (~ 67%) when LIPUS therapy is used to treat hindfoot fusion nonunion.A well-powered, high-quality, randomized controlled trial is needed to demonstrate the clinical and cost effectiveness of LIPUS therapy in foot and ankle surgery.Cite this article: EFORT Open Rev 2021;6:217-224. DOI: 10.1302/2058-5241.6.200045

Stimulation of oral mucosal regeneration by low intensity pulsed ultrasound: an in vivo study in a porcine model.

Many studies have shown the ability of low intensity pulsed ultrasound (LIPUS) to stimulate the bone, cartilage and tendon regeneration but only a few studied LIPUS interest in the regeneration of the oral mucosa. The purpose of this study is to assess the ability of LIPUS to stimulate the regeneration of the palatal mucosa in a porcine model. Ten adults mini-pigs were used. Two mucosal wounds were realised on the left and right side of the palate of each pig. The right side was treated with LIPUS at 1 MHz of frequency and 300 mW/cm2 of acoustic intensity. The left side was not treated. The morphology of the wound was evaluated using a polymer silicone molding. The difference between two sides was significant from day 7 with a p value < 0.0001. At day 21, the wound is completely healed on all pigs with LIPUS. The control soft tissue defect exposed a healing of 80%. The present study showed that the use of LIPUS on the oral mucosa accelerates the healing of the masticatory mucosa.

Is there a role for low intensity pulsed ultrasound (LIPUS) in delayed or nonunion following arthrodesis in foot and ankle surgery?

BackgroundDelayed union and nonunion following foot and ankle arthrodesis is a disabling complication for patients. There are no clinical studies looking at whether there is a role for use of low-intensity pulsed ultrasound (LIPUS) following this. The aim of this study is to investigate the efficacy of LIPUS in this cohort of patients in our centre. MethodsThis was a retrospective observational study reviewing the use of LIPUS in patients who had arthrodesis of a number of different foot and ankle joints diagnosed with delayed or non-union. ResultsOver a 5year period, 18 patients (71st MTPJ fusion, 2 subtalar joints, 2 triple fusion, 4 ankle fusions and 3 isolated midfoot joint) with radiologically confirmed delayed union, were treated with a standardised LIPUS therapy. Twelve patients (67%) were treated successfully with full radiological union confirmed. 4 patients required further surgical revision surgery while 2 were treated conservatively. Isolated small foot joints demonstrated a higher incidence of fusion (9/10; 90%) after LIPUS in comparison to larger or multiple joint arthrodesis (3/8; 38%). ConclusionsThere may be a role for the use of LIPUS as a treatment option in delayed union of isolated, small foot joint arthrodesis. However, we would not recommend its use in large or multiple F&A joint arthrodesis. Large multicentre series are required to confirm our findings.

Improving Patient Compliance with Low-Intensity Pulsed Ultrasound (LIPUS) Treatment (Second Report)

Objective: There are many reports that low-intensity pulsed ultrasound (LIPUS) promotes fracture healing. However, to obtain sufficient therapeutic effect, appropriate use of LIPUS is necessary and patient compliance is very important for that. We reported at this meeting in 2014 about explanation for patients with leaflets, aiming at improvement of compliance. A new model on which calendar function was installed and the implementation rate (actual irradiation days/LIPUS borrowed days) could be clearly indicated has been available since February 2016. In this study, we investigated if the use of the leaflet is meaningful for improving compliance with this new model. Materials and Methods: The subjects were 30 patients who underwent LIPUS at our hospital from April 2016 to March 2017 and were followed up for more than 3 months. The subjects consisted of 15 males and 15 females and the average age was 47.4 years (10–78 years) old. We examined compliance both in the group of 11 cases using the new model with explanatory leaflets and in the group of 19 cases using the new model without leaflet explanation. Results: The average compliance rate of all patients was 83.2% (37.6%–100%). The average rate was 88.8% in the group with explanatory leaflet and 79.9% in the group without the leaflet (P = 0.11). Discussion: Pounder et al reported that the implementation rate was significantly improved by using the new model, indicating the usefulness of the new device. The result of this study suggested that further improvement of compliance could be expected by using the new model and explanatory leaflets.

Dementia May Reduce the Effectiveness of Low-Intensity Pulsed Ultrasound (LIPUS) Following Intramedullary Fixation for Trochanteric Fracture of the Femur

Objectives: Femoral trochanteric fracture often occurs in elderly females with bone fragility, and may accompany the complication of dementia, such as Alzheimer disease. In addition, comminuted fracture and unstable fracture are also confirmed in many cases, but low intensity pulsed ultrasound (LIPUS) is effective in promoting callus formation after osteosynthesis. However, there is a concern that LIPUS may not be effective when dementia develops as a concomitant complication in patients with femoral trochanteric fracture. In this study, we examined the effects of LIPUS to promote callus formation in subjects with and without decreased cognitive function. Subjects and Methods: The inclusion criteria included elderly females who underwent reduction with the use of intramedullary nails of the same type, began to receive load training with no limitation on the day following the surgery, and were followed from surgery to convalescent rehabilitation at our hospital. The exclusion criteria included those who received drugs to increase bone quantity, such as osteoporosis drugs (except for alfacalcidol) and AChEIs, routine steroid administration, or artificial dialysis. The subjects were divided into the decreased cognitive function group with HDS-R of 20 points or less and the non-decreased cognitive function group with 21 points or more. These groups were further divided into the LIPUS treated group and the non-treated group, respectively to compare the appearance of callus confirmed by plain X-ray examination. Results: In the non-decreased cognitive function group, callus formation was significantly promoted by LIPUS, but LIPUS showed no effect in the decreased cognitive function group. Discussions: Patients with dementia, such as Alzheimer disease, exhibit decreased parasympathetic nerve function and decreased bone mass caused by retroplasia of the hypothalamus, as well as protracted synostosis in hip fracture due to dementia. For femoral trochanteric fracture with the complication of decreased cognitive function, concomitant use of LIPUS and AChEIs, which inhibit the aggravation of dementia, may be effective.

The use of low-intensity pulsed ultrasound in treating delayed union of fifth metatarsal fractures

BackgroundThere are no studies looking at the success rate of low-intensity pulsed ultrasound (LIPUS) in fifth metatarsal fracture delayed unions to our knowledge. The aim of this study is to investigate the use of LIPUS treatment for delayed union of fifth metatarsal fractures. MethodsA retrospective review of patients who were treated with LIPUS following a delayed union of fifth metatarsal fracture was conducted over a three-year period. ResultsThere were thirty patients (9 males, 21 females) in this cohort. The average age was 39.3 years. Type 2 fractures made up 43% of our cohort. Twenty-seven (90%) patients went on to progress to union clinically and radiologically following LIPUS treatment. Smoking (p=0.014) was predictive of non-union. Assuming that there were 10 delayed unions a year and 6 went on to non-union as previously suggested by a systematic review, the cost savings of using LIPUS (90% success rate; 10 LIPUS machine and surgery for 1 non-union) vs operative intervention (surgery for 6 non-union) equates to a cost saving of £7765 a year. ConclusionThere is a role for the use of LIPUS in delayed union of fifth metatarsal fractures and can serve as an adjunct prior to consideration of surgery. The findings of this study also suggest the use of LIPUS to be a cost effective treatment modality compared to surgical management. Level of evidenceLevel 4.