Extracorporeal Shock Wave Application Research Articles

Mechanical and microbiological testing concept for activatable anti-infective biopolymer implant coatings.

An anti-infective bilayer implant coating with selectively activatable properties was developed to prevent biofilm formation and to support the treatment of periprosthetic infection as a local adjunct to current treatment concepts. In a first step, Ti6Al4V discs were coated with a permanent layer of Poly(l-lactide) (PLLA) including silver ions. The PLLA could be optionally released by the application of extracorporeal shock waves. In a second step, a resorbable layer of triglyceride (TAG) with incorporated antibiotics was applied. The second layer is designed for resorption within weeks. Prior to approval and clinical application, a comprehensive evaluation process to determine mechanical/physical and microbiological properties is obligate. To date, none of the existing test standards covers both drug-releasing and activatable coatings for orthopedic implants. Therefore, a comprehensive test concept was developed to characterize the new coating in a pilot series. The coatings were homogeneously applied on the Ti6Al4V substrate, resulting in an adhesion strength sufficient for non-articulating surfaces for PLLA. Proof of the extracorporeal shockwave activation of PLLA was demonstrated both mechanically and microbiologically, with a simultaneous increase of biocompatibility compared to standard electroplated silver coating. Wettability was significantly reduced for both layers in comparison to the Ti6Al4V substrate. Thus, potentially inhibiting biofilm formation. Furthermore, the TAG coating promoted cell proliferation and bacterial eradication. In conclusion, the testing concept is applicable for similar biopolymer coating systems. Furthermore, the extracorporeal activation could represent a completely new supportive approach for the treatment of periprosthetic joint infections.

Dose-related effects of extracorporeal shock waves on orthodontic tooth movement in rabbits

The purpose of this animal study is to investigate the quantitative effects of extracorporeal shock waves applied at two different impulses and with two different applicators on orthodontic tooth movement. Thirty-five New Zealand rabbits were randomly divided into five groups (n = 7): the four experimental extracorporeal shock wave groups—focused/500 impulses, focused/1000 impulses, unfocused/500 impulses, and unfocused/1000 impulses—and the control group. Orthodontic tooth movement was achieved by application of reciprocal force between two maxillary incisors. In the experimental groups, animals received 500 or 1000 impulses of extracorporeal shock waves at 0.19 mJ/mm2 with focused or unfocused applicators depending on the group to which they belonged. These experiments were conducted on days 0, 7, and 14. Orthodontic tooth movement was measured with 0.01 mm accuracy at one-week intervals. On days 7 and 21, the bone-specific alkaline phosphatase levels were measured from blood samples. After 21 days, the animals were sacrificed and the area between the two maxillary incisors was stereologically examined. Orthodontic tooth movement in the focused/500 impulses and focused/1000 impulses groups was significantly increased compared to the control group. A significant difference in bone-specific alkaline phosphatase levels between the unfocused/500 impulses and control groups was found at 21st day. Stereological analysis showed that there were significant increases of the formation of new bone, connective tissue, and vessels in the experimental groups. The application of extracorporeal shock waves, especially with a focused applicator, could accelerate orthodontic tooth movement.

Radial extracorporeal shock wave therapy in flexor tendon pathology of the hand: A feasibility study

Radial extracorporeal shock wave therapy (rESWT) is an effective and safe non-invasive therapeutic option for various musculoskeletal pathologies. However, data on possible application of radial extracorporeal shock waves (rESWs) on soft tissue components of fingers is still scarce. We now aimed to analyze the feasibility of applying rESWs to human fingers ex vivo. Fresh frozen human cadaveric fingers were exposed to rESWs of varying energy density. The penetration of the rESWs into the soft tissue was determined using pressure sensitive Fuji films that were placed underneath the flexor tendons and other soft tissue components at the proximal phalanx. Then, rESWs were applied and activation of the Fuji film was recorded. Software based image analysis was performed on all films treated with rESWT under ultrasound gel. Penetration of the rESWs through the soft tissue was detected in all settings. Increasing energy density of the rESWs resulted in increasing film activation. Image analysis of films used under ultrasound showed a significant difference among the groups. The results of this study demonstrate that rESWs can penetrate soft tissues including the flexor tendons of human cadaveric fingers. rESWT should be considered as a valuable potential therapeutic option of different finger pathologies. Further studies focusing on the clinical application of rESWT for finger pathologies are required.

Exposure to radial extracorporeal shockwaves induces muscle regeneration after muscle injury in a surgical rat model

The leading cause of training interruption in sport is a muscle injury, for which the standard treatment is nonsteroidal anti-inflammatory drugs (NSAIDs). To find alternative treatments, we investigated whether the radial extracorporeal shockwave application (rESWT) could stimulate muscle regeneration. A lesion with complete rupture (grade III muscle tear) was set in the musculus rectus femoris of 12-week-old Wistar rats, and the NSAID diclofenac, rESWT, or a combined therapy were applied on day 0, 3, and 5 directly following the surgery. Rats were euthanized at 2, 4, and 7 days after surgery and the area of muscle lesion was excised for histological and gene expression analysis to determine the progress in the healing of damaged fibers and tissue regeneration. The best effect on muscle regeneration was observed in the group treated with rESWT alone. Monotherapy by diclofenac showed a smaller but still positive effect and lowest effects were detected when both therapies were applied. rESWT alone demonstrated a significant upregulation of the muscle markers MyoD and myosin. The presence of myosin gene expression indicated newly formed muscle fibers, which was confirmed by hematoxylin and eosin staining. Seven days after injury the amount of mononucleated cell decreased and regenerating fibers could be detected. This effect is most pronounced in the group treated with rESWT alone. In our study, shockwaves demonstrated the best effect on muscle regeneration. Therefore, we recommend prospective clinical studies to analyze the effect of rESWT after sports trauma to improve muscle regeneration and to shorten the rehabilitation.

Extracorporeal Shock Wave Stimulates Angiogenesis and Collagen Production in Facial Soft Tissue

BackgroundThis study investigated the efficacy of extracorporeal shock wave (ESW) application in stimulating dermal thickness, vascularity, and collagen synthesis of facial skin in a large animal model. Materials and methodsThe facial skin of the maxillary and mandibular areas of goats (n = 6 per group) was treated with ESWs of different intensities (0.15 and 0.45 mJ/mm2; 1000 pulses). After 4 d, histology and immunohistochemistry were used to evaluate the following: dermal thickness, total number and abundance of microvessels, amount of type 1 collagen, and α-smooth muscle actin expression. ResultsDermal thickness, number and abundance of microvessels, and collagen synthesis increased after ESW application at both intensities (each P < 0.05). When comparing ESW groups, the highest collagen abundance was seen after 0.15 mJ/mm2 (P = 0.034), whereas the highest number of microvessels was detected after treatment with 0.45 mJ/mm2 (P = 0.002). ConclusionsA single-session application of focused low-energy ESWs to facial skin can increase dermal thickness by stimulating collagen production and local microcirculation. These findings commend the technique for future investigation for pretreatment of local or microvascular skin flaps to enhance tissue healing.

A Novel Technique for the Standardized Application of Shock Waves in Experimental Research: The Diver Box

The Diver Box is designed to prevent impedance differences, energy loss or damage to neighboring structures caused by the use of shock waves with application gels. The Diver Box is an acrylic glass container filled with tempered water and includes a coupling membrane to prevent the impedance jump from air to water and to avoid the continuous propagation of shock waves into the tissue, maintaining wave dynamics. Different modes of extracorporeal shock waves can be applied to a mouse skin wound without energy loss and protected from harmful phase-reversed waves. Macroscopic changes were seen in only 5% to 12% of tested specimens. Hazardous phase reversal, back reflection and mechanical tissue damage can be avoided by use of the Diver Box, ensuring standardized extracorporeal shock wave application.

Ultrasound and shock-wave stimulation to promote axonal regeneration following nerve surgery: a systematic review and meta-analysis of preclinical studies

Limited regeneration after nerve injury often leads to delayed or incomplete reinnervation and consequently insufficient muscle function. Following nerve surgery, application of low-intensity ultrasound or extracorporeal shock waves may promote nerve regeneration and improve functional outcomes. Because currently clinical data is unavailable, we performed a meta-analysis following the PRISMA-guidelines to investigate the therapeutic effect of ultrasound and shock wave therapies on motor nerve regeneration. Ten ultrasound-studies (N = 445 rats) and three shock-wave studies (N = 110 rats) were identified from multiple databases. We calculated the difference in means or standardized mean difference with 95% confidence intervals for motor function, nerve conduction velocity and histomorphological parameters of treated versus sham or non-treated animals. Ultrasound treatment showed significantly faster nerve conduction, increased axonal regeneration with thicker myelin and improved motor function on sciatic functional index scale (week two: DM[95%CI]: 19,03[13,2 to 25,6], 71 animals; week four: 7,4[5,4 to 9,5], 47 animals). Shock wave induced recovery improvements were temporarily significant. In conclusion, there is significant evidence for low-intensity ultrasound but not for extracorporeal shock wave treatment to improve nerve regeneration. Prospective clinical trials should therefore investigate available FDA-approved ultrasound devices as adjunct postoperative treatment following nerve surgery.

Induction of Endogenous Neural Stem Cells By Extracorporeal Shock Waves After Spinal Cord Injury.

Animal experimental study OBJECTIVES.: The purpose of this study is to investigate the effects of extracorporeal shock waves (ESWs) on endogenous neural stem cells (NSCs) proliferation after spinal cord injury (SCI). Exogenous stem cell transplantation for SCI still has many limitations to be addressed such as ideal cell sources, timing of transplantation, and fate of the transplanted cells. Moreover, the efficacy is another issue owing to a peculiar pathologic condition in the chronic phase of SCI. Contusive SCI was made using 24 Sprague-Dawley rats, and ESWs were applied at post-injury 4 weeks in rats. Proliferation and differentiation of endogenous NSCs (DCX, Sox-2) and axonal sprouting (GAP-43 and MAP-2) were observed at 6 weeks after application of ESWs. Differentiation of the activated neural stem cells was also investigated by coexpression of neuronal/glial cell markers (GFAP, Neu N, and CC-1). Immunofluorescence staining and western blotting were performed for quantitative analysis, and these results were compared with those in the control group. For clinical assessment, the BBB locomotor rating scale was performed. More proliferation of endogenous neural stem cells was noted in the experimental groups, and these activated cells were mainly founded in the ependymal layer of the central canal and the injured posterior horn. Differentiation into neuronal and glial cells was also noted in a limited number of cells. With respect to axonal regeneration, GAP-43 and MAP-2 expressions in the experimental groups were also significantly higher than those in the control group. During 6 weeks' clinical observation following ESWs application, functional improvement of the hindlimb was observed without clinical deterioration by trials. Collectively, these findings indicate that ESWs on the chronic phase of SCI induce activation of endogenous NSCs and consequent functional improvement. N/A.

Application of extracorporeal shockwaves in the treatment of scoliosis: a case report.

[Purpose] In a pilot investigation, extracorporeal shockwave therapy was applied to patients with idiopathic scoliosis. This case report aimed to describe the effects of repeated extracorporeal shockwave therapy on the clinical signs of a patient with scoliosis due to a functional tethered cord syndrome. [Subject and Methods] In June 2016, a 13-year-old girl presented with a left thoracic curvature. Radiograph showed a left thoracic curve of 24°. An angle of trunk rotation of 21° was measured using a scoliometer. Extracorporeal shockwave therapy was proposed to support conservative treatment. Five sessions of extracorporeal shockwave therapy were applied. Finger-floor distance and the angle of trunk rotation before and after each application of extracorporeal shockwave therapy were measured. [Results] The average finger-floor distances before and after extracorporeal shockwave therapy were 22.6 cm and 15.6 cm, respectively. The average angles of trunk rotation before and after the therapy were 13° and 10.2°, respectively. [Conclusion] The short-term effect of extracorporeal shockwave therapy was revealed in this study. The neural structures that inhibited free mobility of the spine were mobilized. Furthermore, deformity was reduced by applying extracorporeal shockwave therapy.

Medical ozone therapy reduces shock wave therapy-induced renal injury

Objectives: Extracorporeal shock wave (ESW) lithotripsy is the preferred treatment modality for uncomplicated kidney stones. More recently free oxygen radical production following ESW application has been considered to be crucial in shock wave-induced renal damage. It has been shown that ozone therapy (OT) has ameliorative and preventive effects against various pathological conditions due to increased nitro-oxidative stress. In current study, we aimed to evaluate the efficacy of OT against ESW-induced renal injury. Methods: Twenty-four male Sprague–Dawley rats were divided into three groups: sham-operated, ESW, and ESW + OT groups. All groups except sham-operated group were subjected to ESW procedure. ESW + OT group received 1 mg/kg/day of oxygen/ozone mixture intraperitoneally at 2 h before ESW, and OT was continued once a day for consecutive three days. The animals were killed at the 4th day, and kidney tissue and blood samples were harvested for biochemical and histopathologic analysis. Results: Serum ALT and AST levels, serum neopterin, tissue nitrite/nitrate levels, and tissue oxidative stress parameters were increased in the ESW group and almost came close to control values in the treatment group (p < 0.05, ESW vs. ESW + OT). Histopathological injury scores were significantly lower in treatment group than the ESW group (p < 0.05, ESW vs. ESW + OT). Immunohistochemical iNOS staining scores in ESW group were higher than those of sham-operated group (p < 0.05, ESW vs. sham-operated), iNOS staining scores in OT group were significantly lower than the ESW group (p < 0.05, ESW + OT vs. ESW). Conclusion: OT ameliorates nitro-oxidative stress and reduces the severity of pathological changes in the experimental ESW-induced renal injury of rat model.

Extracorporeal shock waves improve angiogenesis after full thickness burn

ObjectiveExtensive wounds of burn patients remain a challenge due to wound infection and subsequent septicemia. We wondered whether extracorporeal shock wave application (ESWA) accelerates the healing process. The aim of the study was to analyze microcirculation, angiogenesis and leukocyte endothelium interaction after burns by using ESWA with two types of low intensity. MethodsFull-thickness burns were inflicted to the ears of hairless mice (n=51; area: 1.3mm2). The mice were randomized into five groups: (A) low-energy shock waves after burn injury (0.04mJ/mm2); (B) very low-energy shock waves after burn injury (0.015mJ/mm2); (C) mice received burns but no ESWA (control group); (D) mice without burn were exposed to low-energy shock waves; (E) mice without burns and with no shock wave application. Intravital fluorescent microscopy was used to assess microcirculatory parameters, angiogenesis and leukocyte behavior. ESWA was performed on day 1, 3 and 7 (500 shoots, 1Hz). Values were obtained straight after and on days 1, 3, 7 and 12 post burn. ResultsGroup A showed accelerated angiogenesis (non-perfused area at day 12: 5.3% vs. 9.1% (group B) and 12.6% (group C), p=0.005). Both shock wave groups showed improved blood flow after burn compared to group C. Shock waves significantly increased the number of rolling leukocytes compared to the non-ESWA-treated animals (group D: 210.8% vs. group E: 83.3%, p=0.017 on day 7 and 172.3 vs. 90.9%, p=0.01 on day 12). ConclusionShock waves have a positive effect on several parameters of wound healing after burns, especially with regard to angiogenesis and leukocyte behaviour. In both ESWA groups, angiogenesis and blood flow outmatched the control group. Within the ESWA groups the higher intensity (0.04mJ/mm2) showed better results than the lower intensity group. Moreover, shock waves increased the number of rolling and sticking leukocytes as a part of an improved metabolism.

Extracorporeal shock wave‐induced proliferation of periosteal cells

The cambium cells of the periosteum are an important cell source for select tissue engineering/regenerative medicine applications due to their osteogenic and chondrogenic potential. However, the cambium layer is only 2-5 cells thick, which complicates its harvest, and the low cell number limits its suitability for certain applications. Extracorporeal shock waves (ESWs) have been reported to cause periosteal osteogenesis following cambium layer thickening. This study quantified the proliferation of cambium cells in the femur and tibia of adult rats following ESW treatment at two different energy flux densities. Four days after application of ESWs, there was a significant (3- to 6-fold) increase in cambium layer thickness and cell number. Proliferation was seen with an energy flux density as low as 0.15 mJ/mm(2). The tibial cambium cells were more proliferative than those of the femur, with the cells closest to the ESW source proliferating the most. Within the thickened periosteum, α-smooth muscle actin and von Willebrand Factor expression were upregulated, suggesting a vascular role in ESW osteogenesis. Bone formation was seen within the stimulated periosteum at day 4. We propose that non-invasive ESWs can be used to rapidly stimulate cambium cell proliferation, providing a larger cell population for use as a progenitor cell source for tissue engineering applications, than can normally be provided by periosteum.

Stimulation of bone growth factor synthesis in human osteoblasts and fibroblasts after extracorporeal shock wave application

Nonunion is a common problem in Orthopedic Surgery. In the recent years alternatives to the standard surgical procedures were tested clinically and in vitro. Extracorporeal shock wave therapy (ESWT) showed promising results in both settings. We hypothesized that in target tissue cells from nonunions like fibroblasts and osteoblasts ESWT increases the release of bone growth factors. Fibroblasts and osteoblasts were suspended in 3ml cryotubes and subjected to 250/500 shock waves at 25kV using an experimental electrohydraulic lithotripter. After ESWT, cell viability was determined and cells were seeded at 1×10(5)cells in 12 well plates. After 24, 48, and 72h cell number was determined and supernatant was frozen. The levels of growth factors FGF-2 and TGF-β(1) were examined using ELISA. A control group was treated equally without receiving ESWT. After 24h there was a significant increase in FGF-2 levels (p<0.05) with significant correlation to the number of impulses (p<0.05) observed. TGF-β(1) showed a time-dependent increase with a peak at 48h which was not significantly different from the control group. FGF-2, an important growth factor in new bone formation, was shown to be produced by human fibroblasts and osteoblasts after treatment with ESWT. These findings demonstrate that ESWT is able to cause bone healing through a molecular way by inducing growth factor synthesis.

Microvascular Response to Shock Wave Application in Striated Skin Muscle

This study aims to quantify by intravital microscopy the microhemodynamic response after extracorporeal shock wave application (ESWA) to the physiologic microcirculation of the mouse dorsal skinfold chamber. ESWA was carried out using an electrohydraulic shock wave source. Two different shock wave doses of 500 and 1000 pulses at an energy flux rate of 0.08 mJ/mm(2) and a frequency of 4 Hz were compared with sham-operated animals. Microcirculatory analyses were performed at baseline (BL) and during a 3 d observation period after ESWA. The expression of caspase-3 (casp-3), proliferating cell nuclear antibody (PCNA), von Willebrand factor (vWF), and endothelial nitric oxide synthase (eNOS) were analyzed semiquantitatively by immunohistochemistry. ESWA provoked a significant and persistent increase of functional capillary density (FCD) throughout the observation period, reaching a maximum (140% ± 5% of BL, P < 0.05 versus sham) after 1 d when animals were treated with 1000 pulses. ESWA induced a slight increase of leukocyte rolling (∼2- to ∼3.5-fold, P < 0.05) and leukocyte adherence (∼1.5- to ∼2-fold, P < 0.05) to the endothelial lining of postcapillary venules. One day following ESWA, we observed enhanced expression of casp-3 (∼3- to ∼4-fold), PCNA (∼9- to ∼14-fold), vWF (∼11- to ∼14-fold), and eNOS (∼3-fold), all P < 0.05. This study shows that ESWA provokes a favorable persistent increase of patent capillaries, however accompanied by a transient and slight inflammatory response but also by dose-dependant apoptotic cell death. Our data suggest that ESWA might represent a noninvasive biomechanical tool to treat critically perfused and endangered tissues, but certainly warrants further investigation.

A neural model for chronic pain and pain relief by extracorporeal shock wave treatment

The paper develops a new theory of chronic pain and pain relief by extracorporeal shock wave treatment. Chronic pain without underlying anatomical disorder is looked at as a pathological control function of memory. Conditioned reflexes are considered to be engraved memory traces linking sensory input of afferent signals with motor response of efferent signals. This feature can be described by associative memory functions of the nervous system. Some conditioned reflexes may cause inappropriate or pathological reactions. Consequently, a circulus vitiosus of pain sensation and muscle and/or vessel contraction is generated when pain becomes chronic (pain spiral). The key feature is a dedicated engram responsible for a pathological (painful) reaction. The pain memory may be explained by the concept of a holographic memory model published by several authors. According to this model it is shown how nervous systems may generate and recall memory contents. The paper shows how extracorporeal shock wave treatment may reorganize pathologic memory traces, thus giving cause to real and permanent pain relief. In a generalized manner, the idea of associative memory functions may help in the understanding of conditioning as a learning process and explain extracorporeal shock wave application as an efficient treatment concept for chronic pain. This concept may open the door for new treatment approaches to chronic pain and several other disorders of the nervous system.

Selective loss of unmyelinated nerve fibers after extracorporeal shockwave application to the musculoskeletal system

Application of extracorporeal shockwaves (ESW) to the musculoskeletal system may induce long-term analgesia in the treatment of chronic tendinopathies of the shoulder, heel and elbow. However, the molecular and cellular mechanisms behind this phenomenon are largely unknown. Here we tested the hypothesis that long-term analgesia caused by ESW is due to selective loss of nerve fibers in peripheral nerves. To test this hypothesis in vivo, high-energy ESW were applied to the ventral side of the right distal femur of rabbits. After 6 weeks, the femoral and sciatic nerves were investigated at the light and electron microscopic level. Application of ESW resulted in a selective, substantial loss of unmyelinated nerve fibers within the femoral nerve of the treated hind limb, whereas the sciatic nerve of the treated hind limb remained unaffected. These data might indicate that alleviation of chronic pain by selective partial denervation may play an important role in the effects of clinical ESW application to the musculoskeletal system.

Evaluating the risk of sciatic nerve damage in the rabbit by administration of low and intermediate energy extracorporeal shock waves

The aim of the study was to evaluate the likeliness for peripheral nerve lesions following extracorporeal shock wave application. 82 rabbit sciatic nerves were randomized to undergo low-energetic (0.08 mJ/mm2), middle-energetic (0.28 mJ/mm2) or no (controls) shock wave therapy. After 1 to 28 days an independent neuropathologist checked the specimen for signs of neural lesions. Only after 14 and 28 days vacuolic swelling of the axons was noted, somewhat pronounced in the middle-energetic group. In no case was there any disruption of the nerve's continuity. We did not observe any neurapraxia. Shock wave application does not threaten peripheral nerve integrity in an animal model.

Extracorporeal shockwave application to the distal femur of rabbits diminishes the number of neurons immunoreactive for substance P in dorsal root ganglia L5

Application of extracorporeal shockwaves to the musculoskeletal system can induce long-term analgesia in the treatment of chronic painful diseases such as calcifying tendonitis of the shoulder, tennis elbow and chronic plantar fasciitis. However, the molecular and cellular mechanisms underlying this phenomenon are largely unknown. Recently it was shown that application of extracorporeal shockwaves to the distal femur of rabbits can lead to reduced concentration of substance P in the shockwaves' focal zone. In the present study we investigated the impact of extracorporeal shockwaves on the production of substance P within dorsal root ganglia in vivo. High-energy shockwaves were applied to the ventral side of the right distal femur of rabbits. After six weeks, the dorsal root ganglia L5 to L7 were investigated with high-precision design-based stereology. The application of extracorporeal shockwaves caused a statistically significant decrease in the mean number of neurons immunoreactive for substance P within the dorsal root ganglion L5 of the treated side compared with the untreated side, without affecting the total number of neurons within this dorsal root ganglion. No effect was observed in the dorsal root ganglia L6 and L7, respectively. These data might further contribute to our understanding of the molecular and cellular mechanisms in the induction of long-term analgesia by extracorporeal shockwave application to the musculoskeletal system.

Low-Energy Shock Wave for Enhancing Recruitment of Endothelial Progenitor Cells

Stem and progenitor cell therapy is a novel approach to improve neovascularization and function of ischemic tissue. Enhanced tissue expression of chemoattractant factors such as stromal cell-derived factor 1 and vascular endothelial growth factor is crucial for the recruitment of circulating endothelial progenitor cells (EPCs) during acute ischemia. In chronic ischemia, however, expression of these chemoattractants is less pronounced, which results in insufficient EPC recruitment into the target tissue. Therefore, we investigated the effect of targeted extracorporeal shock wave (SW) application in order to facilitate EPC recruitment into nonischemic and chronic ischemic tissue. Hind limb adductor muscles of nude rats were treated with 500, 1000, and 2000 impulses of focused low-energy SW (flux density level: 0.05 mJ/mm2). Twenty-four hours later, mRNA expression of the chemoattractant stromal cell-derived factor 1 was significantly increased with 1000 impulses (stromal cell-derived factor 1/GAPDH: 0.95+/-0.09) and 2000 impulses (stromal cell-derived factor 1/GAPDH: 1.17+/-0.24; both P<0.05 versus untreated). Histologically, the number of vascular endothelial growth factor-positive endothelial cells per myocyte was significantly increased with 2000 impulses (0.24+/-0.05 versus 0.09+/-0.02; P<0.01). This preconditioning effect resulted in significantly enhanced recruitment and homing of EPCs that were intravenously infused 24 hours after SW treatment (P<0.05). In a rat model of chronic hind limb ischemia, SW-facilitated EPC treatment resulted in a significant increase in relative blood flow recovery as assessed by laser Doppler imaging (P<0.05). Preconditioning of both nonischemic and chronic ischemic tissue with low-energy SW improves recruitment of circulating EPCs via enhanced expression of chemoattractant factors. Thus, SW-facilitated cell therapy may improve the efficacy of EPC treatment in patients with chronic ischemia.

Location Modalities for Focused Extracorporeal Shock Wave Application in the Treatment of Chronic Plantar Fasciitis

Focused extracorporeal shock waves (ESWT) has been used in the treatment of plantar fasciitis with heel spurs. The optimal location for administering treatment, however, has not been determined. The purpose of this study was to determine whether fluoroscopy-guided location of a heel spur or patient location of the maximal point of tenderness is more effective in administering ESWT. In a prospective, examiner-blinded trial, 41 patients were randomized into two groups for treatment by ESWT: group 1, location of the heel spur for ESWT by fluoroscopy, and group 2, patient location for ESWT by maximal point of tenderness. Each group had three session of ESWT at 1-week intervals. The success rates between the two groups were assessed at 6 and 12 weeks. No significant differences were noted between the groups. Despite the small number of patients in the study, patient location for positioning the focus in ESWT in treatment of plantar fasciitis with a heel spur is recommended.