Stimulation of human bone marrow mesenchymal stem cells by electromagnetic transduction therapy - EMTT.

Many different pulsed electromagnetic field (PEMF) devises have been clinically used to stimulate healing processes, but many procedures are still without supporting basic research data. The aim of this study was to investigate a new modified pulsed electromagnetic field therapy: electromagnetic transduction therapy (EMTT). EMTT is technically based on high-intensive PEMFs with a magnetic field strength between 80 and 150 mT. The effect of EMTT for a 10-min session three times a week on human bone marrow mesenchymal stem cells (MSCs) was evaluated by assessing cell viability, gene expression of bone regenerative factors and VEGF-A (vascular endothelial growth factor) secretion after 7 and 14 days of treatment. No negative or toxic effects of EMTT on MSCs in vitro were observed in the applied test frame. The VEGF-ELISA at day 7 of EMTT treatment with 80 mT showed a significant higher VEGF concentration compared to untreated control group. In conclusion, high-intensive electromagnetic impulses showed no harmful effects on MSC cultures in our study. The enhancement of the proangiogenic factor VEGF in MSCs on day 7 indicates a substantial role in cell-stimulating effect of EMTT. Further in vitro and in vivo studies should differentiate specific stimulating and regenerating effects of EMTT impulses in soft tissue engineering. Specific electromagnetic characteristics have to be determined to optimize electromagnetic treatment options in orthopedic surgery and traumatology and soft tissue treatment options.

Current Consensus for Rehabilitation Protocols of the Surgically Repaired Acute Mid-Substance Achilles Rupture: A Systematic Review and Recommendations From the "GAIT" Study Group.

Surgical repair of acute mid-substance Achilles tendon ruptures is performed in active patients, but the postoperative rehabilitation program is often based on the experience of the surgeon or therapist, rather than on evidence-based protocols. The aim of the study is to establish an evidence-based protocol for rehabilitation. This study is a consensus statement. The "GAIT" study group (German, American, and Italian Tendon), an informal collection of 4 experienced foot and ankle surgeons, met to address the question of what items they felt were important relative to rehabilitate a surgically repaired Achilles tendon acute rupture. Thirty-three statements were formulated. A value of 100% agreement by all the members was set to produce a proposed consensus statement. A value of 80% consensus was set to produce "strong recommendation." A systematic review of the literature was also performed. The GAIT group reach 100% agreement on the average postoperative non-weightbearing for 2.3 weeks, the foot in plantarflexion for the first 4 weeks, avoiding ROM exercises beyond neutral, and both stretching and eccentric exercise, not started before 12 weeks. Concentric bilateral heel raises should be performed after 6 weeks, and the average return to initiate sports, was 24.4 weeks. The use of a 1/8th-1/4th inch heel cushions in daily shoes after 8 weeks, the use of an antigravity treadmill for rehabilitation, and the return to sports based on heel raise repetitions is strongly recommended. Given lack of established verified protocols, the recommendations by our experienced panel should be considered. These proposed consensus statements could be used as a basis for larger controlled trials, and develop best practices.

Distribution patterns of foot and ankle tumors: a university tumor institute experience.

BACKGROUND: Bone and soft tissue masses of the foot and ankle are not particularly rare but true neoplasia has to be strictly differentiated from pseudotumorous lesions. Diagnosis is often delayed as diagnostic errors are more common than in other regions. Awareness for this localization of musculoskeletal tumors is not very high and neoplasia is often not considered. The purpose of this study is to provide detailed information on the incidence and distribution patterns of foot and ankle tumors of a university tumor institute and propose a simple definition to facilitate comparison of future investigations. METHODS: As part of a retrospective, single-centre study, the data of patients that were treated for foot and ankle tumors between June 1997 and December 2015 in a musculoskeletal tumor centre were analyzed regarding epidemiologic information, entity and localization. Included were all cases with a true tumor of the foot and ankle. Exclusion criteria were incomplete information on the patient or entity (e.g. histopathological diagnosis) and all pseudotumoral lesions. RESULTS: Out of 7487 musculoskeletal tumors, 413 cases (5,52%) of tumors of the foot and ankle in 409 patients were included (215 male and 198 female patients). The average age of the affected patients was 36 ± 18y (min.3y, max.92y). Two hundred sixty-six tumors involved the bone (64%), among them 231 (87%) benign and 35 (13%) malignant. There were 147 soft tissue tumors (36%), 104 (71%) were benign, 43 (29%) malignant. The most common benign osseous tumor lesions included simple bone cysts, enchondroma and osteochondroma. By far the most common malignant bone tumor was chondrosarcoma. Common benign soft tissue tumors included pigmented villo-nodular synovitis, superifcial fibromatosis and schwannoma whereas the most common malignant members were synovial sarcoma and myxofibrosarcoma. Regarding anatomical localization, the hindfoot was affected most often. CONCLUSIONS: Knowledge of incidence and distribution patterns of foot and ankle tumors will help to correctly assess unclear masses and initiate the right steps in further diagnostics and treatment. Unawareness can lead to delayed diagnosis and inadequate treatment with serious consequences for the affected patient.

Electromagnetic transduction therapy and shockwave therapy in 86 patients with rotator cuff tendinopathy: A prospective randomized controlled trial.

Rotator cuff (RC) tendinopathy is the most common cause of shoulder pain. The effectiveness of electromagnetic transduction therapy (EMTT), a high energetic pulsed electromagnetic field therapy in this field has not been tested yet in combination with extracorporeal shock wave therapy (ESWT). A total of 86 patients with RC tendinopathy were randomized to undergo three sessions of ESWT in combination with 8 sessions of EMTT or sham-EMTT. Both intervention groups experienced significant and clinical relevant decrease of pain at all follow-up visits, and the functionality of the shoulder evaluated by the Constant Murley score increased significantly as well. The combination of EMTT + ESWT produced significantly greater pain reduction in the visual analogue scale compared to ESWT with sham-EMTT after 24 weeks, during which the Constant Murley score improved significantly when the combination of ESWT and EMTT was employed. In patients with RC tendinopathy, electromagnetic transduction therapy combined with extracorporeal shock wave therapy significantly improves pain and function compared to ESWT with sham-EMTT.

Distal femoral replacement with the MML system: a single center experience with an average follow-up of 86 months.

BACKGROUND: The aim of this study was to compare the functional outcomes and complication rates after distal femoral replacement (DFR) performed with the modular Munich-Luebeck (MML) modular prosthesis (ESKA/Orthodynamics, Luebeck, Germany) in patients being treated for malignant disease or failed total knee arthroplasty. METHODS: A retrospective review of patient charts and a functional investigation (involving Musculoskeletal Tumor Society Score [MSTS], American Knee Society Score [AKSS], Oxford Knee Score [OKS], Western Ontario and McMaster Universities Osteoarthritis Index [WOMAC], Toronto Extremity Salvage Score [TESS], the 12-Item Short-Form [SF-12] Health Survey, and a failure classification system developed by Henderson et al.) of DFR cases from 2002 to 2015 were conducted. The indications for DFR were malignant tumor resection in the femur (n = 20, group A) or failure of revision total knee arthroplasty without a history of malignant disease (n = 16, group B). RESULTS: One-hundred and twenty-nine patients were treated during the study period. Of these, 82 were analyzed for complications and implant-survival. Further, 36 patients were available for functional assessment after a mean follow-up of 86 months (range: 24-154). There were 75 complications in total. The overall failure rate for DFR was 64.6% (53/82 patients). The most common failure mechanisms were type III (mechanical failure), followed by type I (soft tissue) and type II (aseptic loosening). The mean MSTS score (out of 30) was 17 for group A and 12 for group B. All the clinical outcome scores revealed an age-dependent deterioration of function. CONCLUSION: DFR is an established procedure to restore distal femoral integrity. However, complication rates are high. Post-procedure functionality depends mainly on the patient's age at initial reconstruction.

Treatment of Medial Tibial Stress Syndrome With Radial Soundwave Therapy in Elite Athletes: Current Evidence, Report on Two Cases, and Proposed Treatment Regimen.

Two case reports of high-level athletes with medial tibial stress syndrome (MTSS), 1 an Olympian with an actual stress fracture, are presented. Successful treatment included radial soundwave therapy, pneumatic leg braces, relative rest using an antigravity treadmill, and temporary foot orthoses. Radial soundwave therapy has a high level of evidence for treatment of MTSS. We also present recent evidence of the value of vitamin D assessment. Both patients had a successful outcome with minimal downtime. Finally, a suggested treatment regimen for MTSS is presented.

Treatment of Plantar Fasciitis With Radial Soundwave "Early" Is Better Than After 6 Months: A Pilot Study.

Extracorporeal shock wave therapy/radial soundwave therapy has been predominantly used for chronic or recalcitrant plantar fasciitis with strong scientific evidence of reliable outcomes. Most of the studies included patients with plantar fasciitis with symptoms >6 months in duration. Only 2 known studies have investigated acute plantar fasciitis, which is <6 weeks in duration. They both found suboptimal results for the use of extracorporeal shock wave therapy. To the best of our knowledge, no studies have investigated radial soundwave therapy for the subacute stage or early stage of plantar fasciitis. Data were prospectively collected from 28 eligible patients who underwent radial soundwave therapy (RSWT) during a 9-month period in 2014. Of the 28 subjects, 14 were enrolled in the "early group" with a symptom duration of <3 months and 14 in the "standard/control" group with a symptom duration of >6 months. The pretreatment and posttreatment visual analog scale scores, Roles-Maudlsey scores, and activity level were recorded and compared. The early implementation of RSWT yielded comparable outcomes when compared with the standard group. RSWT is a valid treatment modality that can be implemented soon after the initial treatment options or first-phase treatment options have failed. Early treatment is more likely to allow for maintenance of patients' activity level. Also, waiting 6 months to treat plantar fasciitis with RSWT results in delays and inferior results. Early treatment is better for active and athletic patients.

Electromagnetic Transduction Therapy for Achilles Tendinopathy: A Preliminary Report on a New Technology.

A parallel prospective feasibility study was performed on 53 patients with chronic mid-portion Achilles tendinopathy (age 44.7 ± 9.1 years). Of the 53 patients, 28 (active group) were treated using a new electromagnetic (pulsed electromagnetic field) transduction therapy device (Cellactor® MT1) and heel cushions. The device produces an electromagnetic field of 80 milliTesla; a total of 8 treatments was performed within 4 weeks in an outpatient setting, without anesthesia, immobilization, or rest. A control group of 25 patients with a similar duration of symptoms was treated with heel cushions only. At the 12-week assessment point, the visual analog scale scores in both groups had significantly decreased, although the active group had significantly improved visual analog scale scores compared with those of the controls. The Role-Maudsley scores had also significantly improved in both the active and the control groups (p < .00001 and p = .0002, respectively). Electromagnetic transduction therapy could potentially be a useful modality for the treatment of Achilles tendinopathy. It should be compared with the current reference standard of extracorporeal shockwave therapy/radial soundwave therapy with similar level I, II, and III studies.

19 years outcome after cementless total hip arthroplasty with spongy metal structured implants in patients younger than 65 years.

BACKGROUND: Cementless fixation of total hip arthroplasties (THAs) is often favored in young, high-demanding patients due to the conservation of valuable bone-stock and easier revision if loosening has occurred. Long-term outcome data of the spongy metal structured implant used in the present study in patients younger than 65 years are still lacking. METHODS: We conducted a retrospective chart review and functional investigation (Merle d'Aubigné score, SF-12) of patients younger than 65 years at implantation treated with a spongy metal structured THA (n = 79) from one orthopedic university center from 1985 to 1989. RESULTS: At a 19-year mean follow-up (range: 15.3 - 21.3 years), the overall stem survival rate was 93.7 %, and the overall cup survival rate was 82.3 %. Revision surgeries of the stem were performed in all cases for aseptic loosening at an average of 15.3 ± 3.5 years after implantation. Acetabular components were revised for aseptic loosening and recurrent dislocation after inlay revision on an average of 11.8 ± 4.7 years after implantation. No other device related complications occurred within the 19-year follow-up period. No correlation was found between time of revision and gender or age. Clinical outcome scores (Merle d'Aubigné score, SF-12) revealed excellent to good results of the implanted THAs in 87 % of patients. CONCLUSIONS: We conclude that spongy metal structured cementless THAs implanted in young patients have an excellent survival and provide trustworthy clinical results at 19 years of follow-up.

Short- to long-term follow-up of total femoral replacement in non-oncologic patients.

BACKGROUND: Compromised bone stock and heavily impaired structural integrity after multiple endoprosthetic revision surgeries can lead to a comparable condition as encountered in musculoskeletal tumor surgery. Total femoral replacement (TFR) can restore femoral integrity and allow patients to resume ambulation. Even though several authors reported their results of TFR, so far many questions are still on debate: Which patients are at risk to experience low functional outcome? Do complications and clinical outcome after TFR depend on the indication for the surgery (e.g. periprosthetic fractures or aseptic loosening) or the age of the patients? The purpose of the present study was to compare complication rates after TFR performed with modular total femur prosthesis MML (Fa. ESKA/Orthodynamics) in patients without malignant disease. METHODS: We conducted a retrospective chart review and functional investigation of patients treated with a TFR for non-oncologic conditions from 1995 to 2015 and a minimum follow-up of 2 years. Complications were recorded according to the Henderson-Classification; outcome was evaluated with established clinical scores. The indication for TFR was periprosthetic fracture (Group A, n = 11) or aseptic loosening (Group B, n = 7) with massive bone defect of the femur deemed unsuitable for conventional arthroplastic or biologic reconstruction. RESULTS: Eighteen patients matched the inclusion criteria and could be investigated clinically after a mean follow-up of 80 months (range: 28-132). Before TFA, all patients had previously undergone multiple operations (range: 1-8). The overall failure rate for any reason was 72% (n = 13/18), leading to a total of 37 surgical revisions with total exchange of TFR in 22% (n = 4/18). Most common failure mechanism was Type I (soft tissue), followed by Type IV (infection) and Type III (mechanical failure). According to Enneking's functional evaluation method (MSTS-Score), the function ranged from 1 to 15 with a mean of 10 ± 4 out of 30. CONCLUSION: TFR is a salvage procedure to restore mechanical integrity and regain functional ability after extensive femoral bone loss. Outcome of the patients in the present study did mainly depend on the age at reconstruction and not on the indication for TFR.

Radial Soundwave for Sesamoidopathy in Athletes: A Pilot Study.

The purpose of the present study was to evaluate the efficacy of radial soundwave therapy (RSW) for the management of sesamoiditis, symptomatic bipartite sesamoids, and avascular necrosis in athletic patients. The data from 10 patients undergoing RSW for sesamoiditis were retrospectively studied. Three treatments at 2.4 Bar and 13 Hz, for a total of 2500 pulses in each session, were administered to the affected sesamoid approximately 1 week apart. The Roles and Maudsley score and the visual analog scale (VAS) were used to assess disability and pain. An overall improvement was seen in reported pain after RSW. The pretreatment VAS score was 5.9 ± 1.7 and the post-treatment VAS score improved to 2.3 ± 2.4 (p = .0001). The activity pretreatment Roles and Maudsley score was 3.1 ± 0.3 and the post-treatment score was 1.5 ± 0.7 (p = .00003). All but 1 of the patients (90%) reported some or complete relief of pain. The mean time to return to activity was 10.1 ± 15.6 weeks, although this value was biased by 1 patient requiring 1 year to return to activity. Eliminating this patient, the average time to return to activity was 5.4 ± 5.6 weeks. Three patients in the cohort did not have to stop their desired activity at all, including 1 gymnast and 1 runner. Of these 3 patients, 2 (20% of all patients) reported complete relief of pain (VAS score of 0) after treatment. The third patient experienced a significant decrease in pain, with the VAS score, improving from 7 to 1. The results of the present study have demonstrated that RSW can be a viable treatment of certain symptomatic sesamoid pathologies and can be considered a valid alternative to surgery.

The Vega advanced third generation posterior stabilized total knee arthroplasty system enables the restoration of range of motion for high demanding daily activities - A 5-years follow-up study.

BACKGROUND: The Vega System® PS (Aesculap AG, Tuttlingen, Germany) is an advanced, third generation fixed implant that aims to mimic natural knee kinematics by optimizing pivotal motion while reducing surface stress. This study evaluated mid-term survival and clinical outcomes, including range of motion (ROM) of the modern posterior stabilized implant in order to analyse whether this biomechanically successful implant reaches good results in situ. METHODS: The first 100 patients to receive the Vega PS System for total knee arthroplasty were invited to take part in this single centre, single surgeon study. Of these, 84 patients were clinically assessed 5-6 years postoperatively. Data which was obtained during this follow-up examination included revision data, range of motion and clinical scores. RESULTS: The 5-year survival rate for exchange of any component was 97.6%, whereby two patients required replacement of the polyethylene gliding surface. Secondary patella resurfacing was performed in 7 patients. Significantly improved results in comparison to the preoperative state could be obtained at the follow-up: KOOS improved from 39.4 to 78.8, SF-12 PCS improved from 32.1 to 42 SF-12 MCS improved from 46 to 53.8 and patella pain improved from 2.7 to 0.3. The mean ROM of the 84 patients after 5 years was 133.1° and mean total KSS was 189.9. DISCUSSION & CONCLUSIONS: This study demonstrates a high survival rate of the Vega PS System® and significant improvements in clinical outcomes 5 years after implantation. The obtained mean ROM indicates that this implant provides good flexibility of the knee joint, allowing a high number of activities. However, due to the rate of secondary patella implantation, routine resurfacing of the patella for all PS TKA cases is highly recommended. CLINICAL TRIALS REGISTRATION: The study was registered at clinicaltrials.gov (NCT02802085).

Topical Treatment Is Effective and Safe for Acute Ankle Sprains: The Multi-Center Double-Blind Randomized Placebo-Controlled TRAUMED Trial.

BACKGROUND: Topical NSAIDs are widely used to treat ankle sprains. Traumed (Tr14) gel is a multicomponent formulation, demonstrating inflammation-resolution properties. METHODS: This multicenter, double-blind trial investigated the efficacy and safety of Tr14 gel versus placebo gel and non-inferiority versus 1% diclofenac gel, applied 3×/day for 7 days after acute lateral ankle sprain (EudraCT Number: 2016-004792-50). The primary outcome was AUC for pain on passive movement, assessed by VAS from baseline to Days 4 and 7. RESULTS: The trial population included 625 patients aged 18 to 78 years. The AUC scores were 187.88 and 200.75 on Day 4 (p = 0.02) and 294.14 and 353.42 on Day 7 (p < 0.001) for Tr14 and placebo, respectively. For Tr14 compared to diclofenac, the AUC scores were 187.50 and 197.19 on Day 4 (p = 0.3804) and 293.85 and 327.93 on Day 7 (p = 0.0017), respectively. On the FAAM-ADL subscale, Tr14 was superior to placebo and non-inferior to diclofenac at all time points. Time to 50% pain improvement was lowest for Tr14 (6.0 days), compared to placebo (7.1 days) and diclofenac (7.0 days). Adverse events were uncommon and minor. CONCLUSIONS: Tr14 gel is effective and safe in acute ankle sprains, compared to placebo gel and diclofenac gel, and has faster pain resolution. TRIAL REGISTRATION: The trial was registered in clinicaltrialsregister.eu, EudraCT number 2016-004792-50 on 07.06.2017.

Extra-corporeal pulsed-activated therapy ("EPAT" sound wave) for Achilles tendinopathy: a prospective study.

Achilles tendinopathy is common and extracorporeal shockwaves have become a popular treatment for this condition, even though previous research has not provided conclusive results regarding its efficacy in cases of Achilles tendinopathy. Our aim was to evaluate 3 weekly shockwave treatments in patients with Achilles tendinopathy, as quantified by the Roles and Maudsley score. A total of 74 tendons in 60 patients were assessed at baseline and at least 1 year posttreatment, including 32 (43.24%) paratendinoses, 23 (31.08%) proximal tendinoses, and 19 (25.68%) insertional tendinoses. The mean age of the participants was 48.6 ± 12.94 years, and patients with paratendinosis (41.44 ± 14.01 years) were statistically significantly younger than those with proximal (53 ± 8.9 years) and insertional (54.26 ± 9.74 years) tendinopathy, and these differences were statistically significant (P = .0012 and P = .0063, respectively). Overall, 58 (78.38%) tendons improved by at least 1 year posttreatment, including 75% in the paratendinosis, 78.26% in the proximal tendinosis, and 84.21% in the insertional tendinosis groups, and no adverse effects were observed. The Roles and Maudsley score improved from 3.22 ± 0.55 to 1.84 ± 1.05 (P < .0001) in the paratendinosis group, 3.39 ± 0.5 to 1.57 ± 0.66 (P < .0001) in the proximal tendinopathy group, and 3.32 ± 0.58 to 1.47 ± 0.7 (P = .0001) in the insertional tendinopathy group. Based on these results, we believe that shockwave therapy serves as a safe, viable, and effective option for the treatment of Achilles tendinopathy.

Long-term Efficacy of Percutaneous Epidural Neurolysis of Adhesions in Chronic Lumbar Radicular Pain: 10 Year Follow-up of a Randomized Controlled Trial.

BACKGROUND: No long-term follow-up data exist in any treatment for chronic radicular pain occurring with disc pathology and after failed back surgery. A previous randomized controlled trial (RCT) has proven efficacy in short-term follow-up as an evidence-based effective therapeutic option. OBJECTIVES: Long term data is needed to determine the efficacy and cost- effectiveness of minimal invasive procedures. The present study reports 10 year follow-up results from the randomized trial. STUDY DESIGN: A prospective, randomized, placebo-controlled, interventional clinical trial. A power calculation was based on a previous feasibility trial. SETTING: University medical centers. METHODS: After a 4 year enrollment phase, 381 patients with chronic radicular pain persisting beyond 4 months, who failed conservative treatments, were screened. Ninety patients were enrolled. Patients were randomly assigned to receive percutaneous epidural lysis of adhesions or placebo with concealed allocation in permuted blocks of 4 to 8 patients each, and stratified by treatment center. The primary outcomes were a mean change of the Oswestry Disability Index (ODI) scores and Visual Analog Scale (VAS), one and 10 years after intervention. For each rating scale an analysis of variance with the within-patient factor time (baseline, one year follow-up, 10 year follow-up) and the between-patient factor treatment (lysis, placebo) was used. RESULTS: Homogeneity was shown at baseline between the groups. The ODI and VAS scores were significantly better one and 10 years in the lysis group vs the control group. The ODI in the lysis group improved from 55.3 ± 11.6 to 9.6 ± 9.3 after one year and to 11.7 ± 14.2 after 10 years. The placebo group also improved from 55.4 ± 11.5 to 30.7 ± 14.2 after one year and to 24.8 ± 12.0 after 10 years. The VAS improved from 6.7 ± 1.1 to 1.2 ± 1.1 after one year and to 1.5 ± 1.4 after 10 years in the lysis group and from 6.7 ± 1.1 to 2.8 ± 1.5 after one year and to 2.9 ± 1.3 after 10 years after placebo intervention. The statistical difference of the ODI and VAS between the treatment and control groups remain significant up to 10 years. No treatment-related severe adverse effects occurred within the 10 years, but minor transient neurological effects were seen directly after the intervention. LIMITATIONS: The long-term effects of single treatment components cannot be specified as no imaging examination was performed at 10 year follow-up. A large variety of unanalyzed noninvasive treatments were done within the 10 years. Some patients did not clearly remember the intervention after 10 years. Uncontrolled effects such as higher inhomogeneity of biometric properties, concomitant therapies, pain tolerance level, or just social effects could occur, but were not analyzed in the trial. CONCLUSION: This is the first 10 year follow-up report of a placebo-controlled RCT showing efficacy of the minimally invasive percutaneous adhesiolysis procedure for patients with chronic lumbosacral radicular pain. No alternative evidence-based treatment modality with 10 year follow-up is available to be recommended. This procedure should be considered as the first treatment option for patients with chronic lumbosacral radicular pain.

An Ex Vivo Bone Defect Model to Evaluate Bone Substitutes and Associated Bone Regeneration Processes.

The increased incidence of bone defects, especially in cases of comminuted fractures or bone tumor resections demands suitable bone grafts and substitutes. The aim of this study was to establish an ex vivo bone defect model to evaluate new bone substitutes and associated repair processes under controlled conditions. Femoral heads derived from patients undergoing total hip replacement were cut into cylinders (20 mm diameter, 7 mm height). A central bone defect (6 mm diameter, 5 mm depth) was inserted centrally. The bone slides were cultured for 28 days and viability was evaluated by lactate dehydrogenase and alkaline phosphatase assay, and Calcein-AM viability staining and DNA quantification. Data revealed the viability of the bone tissue over the tested time period of 28 days, and an increase in cell numbers implicating active cell proliferation processes in the sections. To analyze the bone regeneration potential of this model in combination with a bone replacement material, we injected a collagen-type 1 hydrogel into the central defect. Cellular ingrowth into the gel was evaluated by microscopy and DNA quantification at different time points demonstrating an increase of cells in the defect over time. Finally, gene expression of osteogenic markers indicated an osteoblastic phenotype of the cells in the defect. In summary, the ex vivo bone defect model remains viable and shows active bone repair processes over 28 days. Additional advantages include high reproducibility, manageable costs, and a native bone-implant interface supporting the evaluation of bone substitute materials and associated regeneration processes. Impact statement Testing of new implant materials and bone repair strategies up to date rely mainly on in vivo and in vitro investigation models providing different pros and cons. In this study we established a novel human ex vivo bone defect model with a proven vitality of at least 28 days. The model provides a native bone implant interface and is designed to monitor cell invasion into a critically sized defect filled with the potential implant material. Furthermore, associated repair processes can be documented on the cell and molecular level, including additional advantages such as high reproducibility and manageable costs.

The effect of antibacterial acting extracorporeal shockwaves on bacterial cell integrity.

BACKGROUND: Antibacterial effects of extracorporeal shockwaves (ESWs) have been demonstrated in vitro against bacteria under static and dynamic growth conditions. This study assessed the effects of ESWs on the cell wall integrity of bacteria. MATERIAL/METHODS: Standardized suspensions of Staphylococcus aureus were exposed to various shockwave impulses (2000-12,000) of different energy flux densities (EFD, 0.38-0.96 mJ/mm(2)). Bacterial suspensions of equal concentration that had been permeabilized (to >99%) with isopropanol were used as positive controls. The bacteria of all groups were stained with Sytox Green nucleic acid stain. The fluorescence of the shockwave-treated, permeabilized, and untreated suspensions was measured and compared for bacterial survival, quantified by colony-forming units after plating. RESULTS: Although ESWs showed a significant energy-dependent antibacterial effect that reduced CFUs in the treated suspensions by between 56% and 99%, only maximum energies (4000 impulses at 0.96 mJ/mm(2) and 12,000 impulses at 0.59 mJ/mm(2)) were followed by a significant increase in fluorescence compared with the untreated control (p<0.05). However, the fluorescence of these treated groups was still far less than that of the alcohol-permeabilized positive control groups (p<0.05). Lower energies and impulse rates did not show increased intracellular uptake of the fluorescent dye (p>0.05). CONCLUSIONS: This is the first study to assess bacterial cell wall permeability after ESW treatment. It was found that the permeabilization of bacterial cells after ESW treatment was far less than expected due to the corresponding antibacterial effect. Other mechanisms, such as intracellular effects, might be involved in bacterial killing after ESWs and still must be elucidated.

Energy-dependent stimulatory and inhibitory effects of extracorporeal shock waves on bacteria and on gentamicin activity.

BACKGROUND: Local infection is considered a contraindication for extracorporeal shock wave (ESW) application, although the antibacterial effects of ESW have been clearly demonstrated in vitro. This study aimed to assess the effects of ESW on bacteria under growth-promoting conditions and to evaluate interactions with the activity of gentamicin. MATERIAL/METHODS: Standardized suspensions of Staphylococcus aureus were exposed to 4000 shock wave impulses of various energy flux densities (EFD) both at 37 degrees C in growth medium and at 20 degrees C in saline. Bacterial viability of treatment groups and controls were quantified. Furthermore, the MICs of gentamicin against ESW-treated and untreated suspensions of S. aureus were compared. Finally, suspensions of S. aureus containing graded concentrations of gentamicin were exposed to ESW and bacterial growth was assessed. RESULTS: Antibacterial effects of ESW (0.59-0.96 mJ/mm2) were confirmed with bacteria suspended in normal saline (20 degrees C, p<0.05). However, bacteria suspended in growth medium at 37 degrees C demonstrated significantly increased proliferation (p=0.009) after treatment with shock waves of lower EFD (0.59 mJ/mm2). At higher EFD a significant reduction of bacteria was observed (p=0.009). The MIC of gentamicin against S. aureus was not altered by ESW application. Furthermore, the combination of gentamicin and ESW did not alter gentamicin activity (p>0.05). Nevertheless, a growth-promoting effect of ESW at 0.59 mJ/mm(2) was demonstrated despite simultaneous administration of gentamicin. CONCLUSIONS: This is the first study reporting energy-dependent stimulation of bacterial growth by ESW. Also important is that ESW did not alter the activity of gentamicin.

The minimally invasive anterolateral approach combined with hip onlay resurfacing.

OBJECTIVE: Minimally invasive anterolateral approach in hip resurfacing with complete preservation of muscular integrity. INDICATIONS: Primary or secondary osteoarthritis of the hip. APPROACH: None. Onlay implant: Females>55 years with osteoporosis. Males>60 years with osteoporosis. Severe varus deformity (CCD [collodiaphyseal] angle<100 degrees). History of metal allergy. Clinically relevant renal insufficiency. Radiologic appearance of avascular necrosis stage 3 and 4 according to Ficat. Femoral head cysts>1 cm in diameter. SURGICAL TECHNIQUE: Supine position with possible overextension of the hip, longitudinal incision along the intermuscular septum and blunt intermuscular dissection between gluteus medius and tensor fasciae latae, partial resection of the anterior capsule and anterior dislocation of the hip with complete proximal release of the capsule. Dislocation of the femoral head and dorsal positioning, reaming of the acetabulum to implant the cementless acetabular component, exposition and reaming of the femoral head in extension/adduction and external rotation, implantation of the cemented onlay endoprosthesis. POSTOPERATIVE MANAGEMENT: Prophylaxis of thromboembolism and periarticular ossification. Rehabilitation with weight bearing as tolerated starting on the day of surgery, ergometer training from day 4 after surgery. RESULTS: 31 patients with osteoarthritis underwent onlay resurfacing via a minimally invasive approach. The Harris Hip Score improved from 43.9 to 97.1 at 12 months after surgery. Adverse events such as fracture, dislocation, nerve or muscle lesions did not occur, and clinically significant thromboembolism or infection was not observed.