An investigation of shock wave therapy and low-intensity pulsed ultrasound on fracture healing under reduced loading conditions in an ovine model

Extracorporeal shock wave treatment for post‑surgical fracture nonunion: Insight into its mechanism, efficacy, safety and prognostic factors (Review)

Post-surgical fracture nonunion (PSFN) represents the failure to achieve cortical continuity at radiological examination after an orthopedic operation, which causes a considerable disease burden in patients with fractures. As one of the traditional treatment modalities, surgical therapy is associated with a high fracture union rate; however, post-surgical complications are not negligible. Therefore, less invasive therapies are needed to improve the prognosis of patients with PSFN. Extracorporeal shock wave treatment (ESWT) is a noninvasive method that presents a similar efficacy profile and favorable safety profile compared with surgical treatment. However, the application and detailed mechanism of ESWT in patients with PSFN remain unclear. The present review focuses on the mechanism, efficacy, safety and prognostic factors of ESWT in patients with PSFN, aiming to provide a theoretical basis for its application and improve the prognosis of these patients.

Effects of different physical factors on osteogenic differentiation

Osteoblasts are essential for bone formation and can perceive external mechanical stimuli, which are translated into biochemical responses that ultimately alter cell phenotypes and respond to environmental stimuli, described as mechanical transduction. These cells actively participate in osteogenesis and the formation and mineralisation of the extracellular bone matrix. This review summarises the basic physiological and biological mechanisms of five different physical stimuli, i.e. light, electricity, magnetism, force and sound, to induce osteogenesis; further, it summarises the effects of changing culture conditions on the morphology, structure and function of osteoblasts. These findings may provide a theoretical basis for further studies on bone physiology and pathology at the cytological level and will be useful in the clinical application of bone formation and bone regeneration technology.

Advances in physical diagnosis and treatment of male erectile dysfunction

Erectile dysfunction (ED) is the most common male sexual dysfunction by far and the prevalence is increasing year after year. As technology advances, a wide range of physical diagnosis tools and therapeutic approaches have been developed for ED. At present, typical diagnostic devices include erection basic parameter measuring instrument, erection hardness quantitative analysis system, hemodynamic testing equipment, nocturnal erection measuring instrument, nerve conduction testing equipment, etc. At present, the most commonly used treatment for ED is pharmacological therapy represented by phosphodiesterase five inhibitors (PDE5i). As a first-line drug in clinical, PDE5i has outstanding clinical effects, but there are still some problems that deserve the attention of researchers, such as cost issues and some side effects, like visual disturbances, indigestion, myalgia, and back pain, as well as some non-response rates. Some patients have to consider alternative treatments. Moreover, the efficacy in some angiogenic EDs (diabetes and cardiovascular disease) has not met expectations, so there is still a need to continuously develop new methods that can improve hemodynamics. While drug have now been shown to be effective in treating ED, they only control symptoms and do not restore function in most cases. The increasing prevalence of ED also makes us more motivated to find safer, more effective, and simpler treatments. The exploration of relevant mechanisms can also serve as a springboard for the development of more clinically meaningful physiotherapy approaches. Therefore, people are currently devoted to studying the effects of physical therapy and physical therapy combined with drug therapy on ED. We reviewed the diagnosis of ED and related physical therapy methods, and explored the pathogenesis of ED. In our opinion, these treatment methods could help many ED patients recover fully or partially from ED within the next few decades.

A Systematic Review of Animal Models of Disuse-Induced Bone Loss

OBJECTIVE

Several different animal models are used to study disuse-induced bone loss. This systematic review aims to give a comprehensive overview of the animal models of disuse-induced bone loss and provide a detailed narrative synthesis of each unique animal model.

METHODS

PubMed and Embase were systematically searched for animal models of disuse from inception to November 30, 2019. In addition, Google Scholar and personal file archives were searched for relevant publications not indexed in PubMed or Embase. Two reviewers independently reviewed titles and abstracts for full-text inclusion. Data were extracted using a predefined extraction scheme to ensure standardization.

RESULTS

1964 titles and abstracts were screened of which 653 full-text articles were included. The most common animal species used to model disuse were rats (59%) and mice (30%). Males (53%) where used in the majority of the studies and genetically modified animals accounted for 7%. Twelve different methods to induce disuse were identified. The most frequently used methods were hindlimb unloading (44%), neurectomy (15%), bandages and orthoses (15%), and botulinum toxin (9%). The median time of disuse was 21 days (quartiles: 14 days, 36 days) and the median number of animals per group subjected to disuse was 10 (quartiles: 7, 14). Random group allocation was reported in 43% of the studies. Fewer than 5% of the studies justified the number of animals per group by a sample size calculation to ensure adequate statistical power.

CONCLUSION

Multiple animal models of disuse-induced bone loss exist, and several species of animals have successfully been studied. The complexity of disuse-induced bone loss warrants rigid research study designs. This systematic review emphasized the need for standardization of animal disuse research and reporting.

Review on experimental study and clinical application of low-intensity pulsed ultrasound in inflammation

Low-intensity pulsed ultrasound (LIPUS), as physical therapy, is widely used in both research and clinical settings. It induces multiple bioeffects, such as alleviating pain, promoting tissue repair, and shortening disease duration. LIPUS can also mediate inflammation. This paper reviews the application of LIPUS in inflammation and discusses the underlying mechanism. In basic experiments, LIPUS can regulate inflammatory responses at the cellular level by affecting some signaling pathways. In a clinical trial, LIPUS has been shown to alleviate inflammatory responses efficiently. As a cheap, safe, and convenient physical method, LIPUS is promising as anti-inflammatory therapy.

Direct electromagnetic coupling for non-invasive measurements of stability in simulated fracture healing

Diagnostic monitoring and prediction of bone fracture healing is critical for the detection of delayed union or non-union and provides the requisite information as to whether therapeutic intervention or timely revision are warranted. A promising approach to monitor fracture healing is to measure the mechanical load-sharing between the healing callus and the implanted hardware used for internal fixation. The objectives of this study were to evaluate a non-invasive measurement system in which an antenna electromagnetically couples with the implanted hardware to sense deflections of the hardware due to an applied load and to investigate the efficacy of the system to detect changes in mechanical load-sharing in an ex vivo fracture healing model. The measurement system was applied to ovine metatarsal bones treated with osteotomies, resulting in four different levels of bone stability which simulated various degrees of fracture healing. Computational finite element simulations supplemented these ex vivo experiments to compare the osteotomy model of fracture healing to a more clinically applicable callus stiffening model of healing. In the ex vivo experiments, the electromagnetic coupling system detected significant differences between the four simulated degrees of healing with good repeatability. Computational simulations indicated that the experimental model of fracture healing provided a good surrogate for studying healing during the early time period as the callus stiffness is increasing as well as when diagnostic monitoring of the healing process is most critical. Based upon the data reported herein, the direct electromagnetic coupling method holds strong potential for clinical assessments and predictions of fracture healing. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res.

Low-Intensity Pulsed Ultrasound Treatment Accelerates Angiogenesis by Activating YAP/TAZ in Human Umbilical Vein Endothelial Cells

As a non-invasive method, low-intensity pulsed ultrasound (LIPUS) can accelerate fracture healing. The mechanisms responsible for the enhanced fracture healing need to be studied further. Activation of YAP/TAZ, key mediators of the Hippo signaling pathway, could promote angiogenesis and vascular remodeling. The purpose of this study was to determine whether LIPUS treatment can activate YAP/TAZ. Human umbilical vein endothelial cells (HUVEC) were used. After LIPUS treatment, Western blot and immunofluorescence staining were used for YAP/TAZ activation. Small interfering RNA (siRNA) of YAP and short hairpin LATS1/2 (shLATS1/2) were used to check whether there is cross-talk with the Hippo pathway. The phosphorylated YAP (p-127 and p-397) protein increased more than 3-fold 0.5 h after LIPUS treatment (p < 0.05). TAZ protein increased 3.0-, 2.0- and 1.5-fold 0.5, 6 and 12 h after LIPUS treatment. We found that LIPUS treatment activates YAP/TAZ, which is translocated into the cell nucleus to activate target genes. This process can be inactivated by siYAP and activated by shLATS1/2. The cross-talk with the Hippo pathway can initiate angiogenesis so as to accelerate fracture healing by LIPUS.