The efficacy and safety of patient-specific instrumentation in primary total knee replacement: a systematic review and meta-analysis.

INTRODUCTION: Patient-specific instrumentation (PSI) for primary total knee arthroplasty (TKA) surgery has been shown to increase accuracy of component positioning. However, it is unclear whether this also translates to actual benefits for patients in terms of better outcomes (efficacy) or less complications such as revisions (safety). We therefore systematically reviewed the literature to determine the efficacy and safety of PSI in primary TKA. METHODS: Randomized controlled trials comparing PSI to non-PSI in primary TKA were included. A random effects model was used with meta-regression in case of heterogeneity. RESULTS: Forty-three studies were included with a total of 1816 TKA in the PSI group and 1887 TKA in the control group. There were no clinically relevant differences between the PSI-group and non-PSI group regarding all outcomes. There was considerable heterogeneity: meta-regression analyses showed that the year the study was published was an important effect modifier. Early publications tended to show a positive effect for PSI compared to non-PSI TKA, whereas later studies found the opposite. CONCLUSION: Based on evidence of moderate certainty, our study suggested that there were no clinically relevant differences in efficacy and safety between patients treated with PSI TKA and patients treated with non-PSI TKA.

Translation and Validation of 'Foot Health Status Questionnaire' in Dutch.

The aim of our study was to develop a Dutch version of the Foot Health Status Questionnaire (FHSQ-NL) and evaluate its measurement properties according to the COSMIN definition (COnsensus-based Standards for the selection of health Measurement INstruments). After translation of the FSHQ, a group of 119 randomly selected patient who visited the outpatient clinic for conditions affecting the foot and ankle were asked to participate, of which103 patients were included in the analysis. The FHSQ-NL, a validated Dutch FAOS and a visual analogue scale (VAS) for pain and function were used in this study as outcomes measures. Reliability was assessed by calculating intraclass correlation coefficient (ICC), internal consistency by Cronbach's alpha, and the smallest detectable change (SDC). Construct validity was evaluated by use of a priori hypotheses concerning Spearman's correlation coefficient between FHSQ subscales and FAOS and VAS. All domains of the FHSQ-NL, besides 'General health,' indicated good internal consistency with a Cronbach's alpha ranging from 0.61 to 0.91. Test-retest reliability of all FHSQ domains was poor with an ICC ranging from 0.47 to 0.77. At individual level, the SDC ranged from 35.1 to 60.6 and at a group level (n = 50) from 5.0 to 8.6. Construct validity was supported by confirmation of 75% of all a priori hypotheses. The FHSQ-NL has good internal consistency and smallest detectable change (SDC) at group level. However, reliability and SDC on individual level show suboptimal results. Therefore, the questionnaire is more suitable for evaluating foot complaints at group level instead of individual level.

Total knee arthroplasty improves gait adaptability in osteoarthritis patients; a pilot study.

Background: Gait adaptability is of utmost importance for keeping balance during gait in patients with knee osteoarthritis, also after total knee arthroplasty (TKA). The aims of this explorative study are: (1) assess the effect of age, knee osteoarthritis and TKA on gait adaptability; (2) assess changes in gait adaptability pre-to post-TKA and (3) their relation to functional outcomes. Methods: Gait adaptability was measured using a Target Stepping Test (TST) in knee osteoarthritis patients before (preTKA) and 12 months after TKA (postTKA) and compared to asymptomatic old (AsOld) and young adults (AsYng). TST imposed an asymmetrical gait pattern with projected stepping targets at high walking speed. Gait adaptability was determined through stepping accuracy on the targets. The Oxford Knee Score (OKS) and Timed-Up-and-Go test (TUG) measured patients' physical function. Results: 12 preTKA, 8 postTKA, 18 AsYng, 21 AsOld were tested. Age showed no effect on TST-stepping accuracy. PreTKA showed worse TST-stepping accuracy compared to AsYng and AsOld (7.7; 6.2 cm difference). PostTKA showed an improvement of 52% in TST-stepping accuracy compared to preTKA (3.2 cm).Higher stepping accuracy preTKA predicted higher stepping accuracy post-TKA. In addition, low preTKA stepping accuracy predicted more improvement postTKA. Pre-to post-TKA improvement of stepping accuracy was related to improvement on the TUG (Beta = 0.17, p = 0.024), but not to OKS. Conclusions: Gait adaptability is improved following TKA in knee osteoarthritis patients and no longer significantly worse than asymptomatic adults. The relation of gait adaptability to function is shown by its relation to the TUG and shows to have predictive value pre-to post-TKA.

Limited knee extension during gait after total knee arthroplasty is related to a low Oxford Knee Score.

BACKGROUND: After total knee replacement (TKR) some patients report low self-perceived function, which is clinically measured using patient reported outcome measures (PROMs). However, PROMs, e.g. the Oxford Knee Score (OKS), inherently lack objective parameters of knee function. Biomechanical gait analysis is an objective and reliable measurement to quantitatively assess joint function. Therefore, the aim of this study was to explore the relationship between biomechanical gait parameters and the OKS. METHODS: Gait analyses were recorded in 37 patients at least one year after primary TKR and in 24 healthy controls. Parameters from this analysis were calculated for hip, knee and ankle joint angles and joint moments in the sagittal and frontal plane including initial contact, early, late stance and swing. For the patients these parameters were expressed as its difference to control values at matched walking speed. Linear regression analyses were performed between the parameters from gait analysis and the OKS, with speed as covariate. RESULTS: The difference in knee extension angle at initial contact and late stance between patients and controls was significantly related to the OKS. Per one degree knee extension difference increase, the OKS reduced with 1.0 to 1.6 points. Overall, patients extended their knee less than controls. Neither ankle and hip gait parameters, nor joint moments showed a relation with OKS. CONCLUSIONS: All patients with a submaximal score on the OKS showed limited knee extension during gait, even without a mechanical constraint in knee extension. This could be related to motor control limitations in this patient group.

Matching walking speed of controls affects identification of gait deviations in patients with a total knee replacement.

BACKGROUND: The assessment of functional recovery of patients after a total knee replacement includes the quantification of gait deviations. Comparisons to comfortable gait of healthy controls may incorrectly suggest biomechanical gait deviations, since the usually lower walking speed of patients already causes biomechanical differences. Moreover, taking peak values as parameter might not be sensitive to actual differences. Therefore, this study investigates the effect of matching walking speed and full-waveform versus discrete analyses. METHODS: Gait biomechanics of 25 knee replacement patients were compared to 22 controls in two ways: uncorrected and corrected for walking speed employing principal component analyses, to reconstruct control gait biomechanics at walking speeds matched to the patients. Ankle, knee and hip kinematics and kinetics were compared over the full gait cycle using statistical parametric mapping against using peak values. FINDINGS: All joint kinematics and kinetics gait data were impacted by applying walking speed correction, especially the kinetics of the knee. The lower control walking speeds used for reference generally reduced the magnitude of differences between patient and control gait, however some were enlarged. Full-waveform analysis identified greater deviating gait cycle regions beyond the peaks, but did not make peak value analyses redundant. INTERPRETATION: Matching walking speed of controls affects identification of gait deviations in patients with a total knee replacement, reducing deviations confounded by walking speed and revealing hidden gait deviations related to possible compensations. Full-waveform analysis should be used along peak values for a comprehensive quantification of differences in gait biomechanics.

No differences in cost-effectiveness and short-term functional outcomes between cemented and uncemented total knee arthroplasty.

BACKGROUND: There is an ongoing debate regarding optimal fixation of total knee arthroplasty (TKA), however cost has not been addressed as profoundly. Therefore, the current study primarily aimed to compare costs and cost-effectiveness 1 year after cemented or uncemented TKA. A secondary objective was to compare short-term functional outcomes between both groups. METHODS: A posthoc prospective observational multicenter cohort study of 60 cemented and 50 uncemented Low Contact Stress (LCS) knee systems. Outcome was evaluated using the EuroQol5D-3 L (EQ5D) index, in order to calculate quality adjusted life years (QALYs). Total costs were calculated considering direct costs within the hospital setting (inpatient cost) as well as direct and indirect costs outside the hospital. Cost-effectiveness (total costs per QALY), Oxford Knee Score (OKS) and Numeric Rating Scale (NRS) were compared between cemented and uncemented cases at 1 year after surgery. HealthBASKET project, a micro-costing approach, represents the Dutch costs and situation and was used to calculate hospital stay. (In) direct costs outside the healthcare (medical cost and productivity cost) were determined using two validated questionnaires. RESULTS: Median costs per QALY were similar between cemented and uncemented TKA patients (€16,269 and €17,727 respectively; p = 0.50). Median OKS (44 and 42; p = 0.79), EQ5D (0.88 and 0.90; p = 0.82) and NRS for pain (1.0 and 1.0; p = 0.48) and satisfaction (9.0 and 9.0; p = 0.15) were also comparable between both groups. CONCLUSION: For this type of knee implant (LCS), inpatient hospital costs and costs after hospitalization were comparable between groups.

Measurement properties of the most commonly used Foot- and Ankle-Specific Questionnaires: the FFI, FAOS and FAAM. A systematic review.

PURPOSE: In the foot and ankle literature, a wide range of patient-reported outcome measures (PROMs) is used, however, consensus as to which PROMs are preferred is lacking. Selection of a PROM is among other reasons, often based on measurement properties without considering the methodological quality of the studies that evaluate these measurement properties. The aim of current study was first to identify the most frequently used foot and ankle-specific PROMs in recent orthopaedic foot and ankle literature, and second to conduct a systematic review to synthesize and critically appraise the measurement properties of these PROMS. METHODS: Six PubMed indexed journals focussing on foot and ankle research were screened to identify most commonly used foot and ankle-specific PROMs over a 2 year period (2015-2016). Subsequently, a systematic literature search was performed in PubMed, EMBASE, SPORTDiscus and Scopus to identify relevant studies on their measurement properties. Methodological quality assessment was performed using the COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) checklist, criteria for good measurement properties were applied, and a level of evidence was determined for the measurement properties of each domain of the questionnaires. RESULTS: The three most frequently reported PROMs were the Foot Function Index (FFI), the Foot and Ankle Outcome Score (FAOS) and the Foot and Ankle Activity Measure (FAAM). Among 2046 unique citations, 50 studies were included evaluating these PROMs. Evidence to support the measurement properties of the FFI was mainly lacking due to poor methodological quality. More evidence was available for the measurement properties of the FAOS and the FAAM, but overall evidence supporting all measurement properties is not yet sufficient. CONCLUSION: The best available evidence retrieved in this review showed that the FAOS and the FAAM are promising outcome measures for evaluation of patients with foot and ankle conditions, but their shortcomings should be taken into account when interpreting results in clinical setting or trials. LEVEL OF EVIDENCE: I.

[Subpectoral tenodesis of the long head of the biceps tendon with an interference screw and a cortical button : Clinical and cosmetic results after 1 year]. / Subpektorale Tenodese der langen Bizepssehne mittels Interferenzschraube und Cortical-Button : Klinische und kosmetische Ergebnisse nach einem Jahr.

BACKGROUND: Pathologies of the long head of biceps tendon (LHB) can cause anterior shoulder pain. Surgical treatment includes tenotomy and tenodesis (TD), however TD causes fewer cosmetic deformities and less cramping of the biceps muscle. To date, numerous techniques for TD have been described but the "gold standard" has not yet been established. OBJECTIVES: The purpose of this study is to evaluate the functional and cosmetic outcome following subpectoral biceps TD with an interference screw and a cortical-button (STLHB-IC) after 1 year. MATERIALS AND METHODS: 35 patients (10 female, 25 male) with an average age of 57.4 ± 7 years were examined after STLHB-IC with a follow up of 12.8 ± 1.2 months. The constant score (CS), the long head of biceps score (LHBS) and the subjective shoulder value (SSV) were assessed. Furthermore, the cosmetic result was evaluated by the patient and the examiner, and the elbow flexion strength (EFS) was measured. RESULTS: The CS (82.5 ± 17.2), LHBS (90.1 ± 11.5) and SSV (83.2 ± 17.7) showed good and excellent results. The SSV increased significantly pre vs. postoperatively (40.6 ± 19.7 vs. 83.2 ± 17.7). The CS (82.5 ± 17.2) and the LHBS (90.1 ± 11.5), as well as the EFS (17.5 ± 4.8 kg) of the affected shoulder revealed no significant differences compared with the non-affected shoulder (CS: 91.8 ± 11.3, LHBS: 99.1 ± 11.5; EFS: 19.7 ± 4.8). Severe Popeye deformities (measured by LHBS) were found in 6% of the cases, however if they occurred patients (13.4 ± 3.8) evaluated them as significantly less disadvantageous than the examiners (11.9 ± 4.7). There were no neurovascular injuries, infections or fractures. CONCLUSION: STLHB-IC is a safe, reproducible technique with convincing functional and cosmetic results that provides high patient satisfaction.

First Report of Late Blight Caused by Phytophthora infestans Clonal Lineage US-23 on Potato in Idaho.

Late blight, caused by Phytophthora infestans (Mont.) de Bary, is a destructive disease of potato (Solanum tuberosum) and tomato (S. lycopersicum) in the United States. Prior to 2007, the US-8 clonal lineage was the predominant genotype in the United States (4). Since 2007, a significant genetic change in the population of P. infestans occurred in the eastern United States with the appearance of new isolates with unique genotypes and epidemiological characteristics (3). These new genotypes US-22, US-23, and US-24 are sensitive to metalaxyl and represent mating types A2, A1, and A1, respectively (1,2). Prior to 2012, only US-8 had been documented in Idaho (5). In 2013, late blight was discovered in late August on potato crops (cv. Russet Norkotah) in Bingham and Madison counties, ID. Infected foliage (four samples from Bingham County and five from Madison) was sent to Michigan State University and the University of Wisconsin for confirmation of P. infestans and characterization of the isolates. Five sections from the leading edge of lesions were excised with a sterilized scalpel and placed on potato tuber slices ('Dark Red Norkotah'). Pathogen sporulation on the excised lesions was enhanced by incubation in plastic boxes lined with moistened paper towels for 5 days at 18°C in the dark. The sporulating lesions were transferred onto pea agar medium (160 g peas, 5 g sucrose, 15 g agar, 700 ml distilled water) amended with 50 mg/ml vancomycin. Ten pure cultures were obtained for each of 4 isolates per county by hyphal tipping. Cellulose acetate electrophoresis was conducted to determine Gpi allozyme genotype of the 4 isolates (4). The allozyme banding patterns were 100/100 at the Gpi locus, consistent with previously reported analyses of the US-23 genotype (1,2). Genomic DNA was extracted from 10 pure cultures using the DNeasy Plant Mini Kit (Qiagen, Germantown, MD), and SSR analyses were performed. Microsatellite markers Pi02, Pi4B, Pi63, PiG11, and D13 were used in SSR analyses. Pi02, Pi4B, and Pi63 had alleles of 162/164, 213/217, and 270/279 bp in size, respectively which is consistent with the reference US-23 genotype (1). However, heterozygosity was detected at locus D13 in the Idaho genotype with allele size of 134/210 bp and an additional allele of 140/155/176 bp at locus PiG11. This is different from the standard US-23 genotype (homozygous alleles 134/134 at locus D13 and two alleles 140/155 at locus PiG11). These allele changes indicate the isolates may be variants of US-23 isolates as all other phenotypic characteristics were similar to those of reference US-23 isolates. The Idaho genotypes were sensitive to metalaxyl both in vitro on rye A agar medium amended with metalaxyl at <0.1 ppm, and in vivo on Ridomil treated foliage tests at <0.1 ppm (1,2). Mating type assays confirmed the pathogen to be the A1 mating type. In the 2009 and 2010 late blight epidemics in the eastern United States, US-23 was the predominant genotype, but to our knowledge this genotype has never been reported previously in Idaho. Thus, this is the first known report of P. infestans genotype US-23 causing late blight on potato in Idaho, indicating a change in the population of P. infestans. In Idaho, the source of this genotype remains unknown, although infected tomatoes have been implicated in the widespread dissemination of this genotype of P. infestans in the eastern United States. References: (1) G. Danies et al. Plant Dis. 97:873, 2013. (2) C. Hu et al. Plant Dis. 96:1323, 2012. (3) K. Deahl. (Abstr.) Phytopathology 100:S161, 2010. (4) S. B. Goodwin et al. Plant Dis. 79:1181, 1995. (5) USAblight. Recent US Genotypes. Online: www.usablight.org/node/52 , retrieved 3 January 2014.

Preoperative strength training for elderly patients awaiting total knee arthroplasty.

Objective. To investigate the feasibility and effects of additional preoperative high intensity strength training for patients awaiting total knee arthroplasty (TKA). Design. Clinical controlled trial. Patients. Twenty-two patients awaiting TKA. Methods. Patients were allocated to a standard training group or a group receiving standard training with additional progressive strength training for 6 weeks. Isometric knee extensor strength, voluntary activation, chair stand, 6-minute walk test (6MWT), and stair climbing were assessed before and after 6 weeks of training and 6 and 12 weeks after TKA. Results. For 3 of the 11 patients in the intensive strength group, training load had to be adjusted because of pain. For both groups combined, improvements in chair stand and 6MWT were observed before surgery, but intensive strength training was not more effective than standard training. Voluntary activation did not change before and after surgery, and postoperative recovery was not different between groups (P > 0.05). Knee extensor strength of the affected leg before surgery was significantly associated with 6-minute walk (r = 0.50) and the stair climb (r - = 0.58, P < 0.05). Conclusion. Intensive strength training was feasible for the majority of patients, but there were no indications that it is more effective than standard training to increase preoperative physical performance. This trial was registered with NTR2278.

First Report of Zebra Chip Disease and "Candidatus Liberibacter solanacearum" on Potatoes in Idaho.

In September 2011, potato (Solanum tuberosum L.) tubers graded in a packing facility in south-central Idaho were observed with internal discolorations suggestive of zebra chip disease (ZC). Symptoms were observed in 1 to 2% of tubers of cv. Russet Norkotah and included brown spots and streaks especially in and near the vascular tissue. Some tubers also showed a dark and sunken stolon attachment typical of ZC (1). Initially, tissue samples were taken from seven symptomatic tubers and tested by PCR for "Candidatus Liberibacter solanacearum", the bacterium associated with ZC. Primers specific for the 16S rDNA (primers CLipoF [4] and OI2c [3]) and the outer membrane protein (OMB 1482f and 2086r) (2) were used. Six of these samples were positive for the bacterium. The amplified 16S rDNA and OMB products from two symptomatic tubers of cv. Russet Norkotah were cloned and three clones of each were sequenced. The 16S sequences (1,071 bp; GenBank Accession Nos. JN848755 and JN848756) from the two tubers varied by one nucleotide and had 99 to 100% sequence identity to numerous "Ca. L. solanacearum" sequences in GenBank (e.g., Accession Nos. HM246509, FJ957897, and EU935004). Sequences of the two OMB clones (605 bp; GenBank Accession Nos. JN848757 and JN848758) had 97% sequence identity to the two "Ca. L. solanacearum" OMB sequences in GenBank (Accession Nos. CP002371 and FJ914617). Six of eight additional symptomatic field-collected cv. Russet Norkotah tubers corresponding to tubers collected in the packing facility were also positive for "Ca. L. solanacearum" by PCR. Additional severely symptomatic tubers of cvs. Russet Burbank, Yukon Gold, and raw cut French fries of Ranger Russet produced in south-central Idaho were subsequently tested by PCR and were found to be positive for "Ca. L. solanacearum" as well. On the basis of the symptoms, specific PCR amplification with two distinct primer pairs and DNA sequence analysis, zebra chip disease caused by "Ca. L. solanacearum" was determined to be present in Idaho. This disease has caused significant economic damage to potatoes in many regions, including Texas, Mexico, Central America, and New Zealand (1). Idaho is the largest potato-producing state in the United States, with over 150,000 ha planted this year, and therefore, ZC potentially poses a significant risk to agriculture in this state. References: (1) J. M. Crosslin et al. Online publication. doi:10.1094/PHP-2010-0317-01-RV, Plant Health Progress, 2010. (2) J. M. Crosslin et al. Southwest. Entomol. 36:125, 2011. (3) S. Jagoueix et al. Mol. Cell. Probes 10:43, 1996. (4) G. A. Secor. Plant Dis. 93:574, 2009.

[Rehabilitation of Parkinson's patients with deep brain stimulation. Experiences of the Neurological Rehabilitation Center Godeshöhe]. / Rehabilitation von Parkinson-Patienten mit Tiefenhirnstimulation. Erfahrungen des Neurologischen Rehabilitationszentrums Godeshöhe.

BACKGROUND: Deep brain stimulation (DBS) of the subthalamic nucleus (STN) has become an important therapeutic option in patients with advanced Parkinson's disease (PD). An increasing number of patients are referred for hospital rehabilitation after initial programming. The role of further DBS and medication adjustments for this rehabilitation therapy is uncertain. METHODS: This study was a retrospective analysis of a hospital rehabilitation program with a systematic algorithm to improve DBS efficacy in PD patients referred within 3 months after electrode implantation. This study analyzed (1) changes of stimulation parameters and medication and (2) changes in the performance of activities of daily living as measured by the Barthel index. RESULTS: After an average of 20.4±10.7 days following surgery 95 PD patients were hospitalized for an average rehabilitation period of 29.0±11.2 days. Technical dysfunctions were found in 3 (3.1%) patients and a bilateral electrode dislocation in 1 (1.1%) patient. Stimulation parameters were adjusted on 7.3±4.0 days, sometimes with several adjustments on the same day. Until discharge the stimulation amplitude was significantly increased from 2.1±0.8 V to 3.0±0.8 V. Moreover, in 70 (73.7%) patients active stimulation contacts were changed. The mean levodopa equivalent dosage decreased from 529±290 mg/die to 300±277 mg/die. The Barthel index increased significantly by 10.3±12.4 points. CONCLUSION: Further DBS and medication adjustments play an important role for hospital rehabilitation of PD patients after initial DBS programming in DBS centers.

Treatment of malunited fractures of the ankle: A long-term follow-up of reconstructive surgery.

In this retrospective study, using the prospectively collected database of the AO-Documentation Centre, we analysed the outcome of 57 malunited fractures of the ankle treated by reconstructive osteotomy. In all cases the position of the malunited fibula had been corrected, in several cases it was combined with other osteotomies and the fixation of any non-united fragments. Patients were seen on a regular basis, with a minimum follow-up of ten years. The aim of the study was to establish whether reconstruction improves ankle function and prevents the progression of arthritic changes. Good or excellent results were obtained in 85% (41) of patients indicating that reconstructive surgery is effective in most and that the beneficial effects can last for up to 27 years after the procedure. Minor post-traumatic arthritis is not a contraindication but rather an indication for reconstructive surgery. We also found that prolonged time to reconstruction is associated negatively with outcome.

Shape changes of supported Rh nanoparticles during oxidation and reduction cycles.

The microscopic insight into how and why catalytically active nanoparticles change their shape during oxidation and reduction reactions is a pivotal challenge in the fundamental understanding of heterogeneous catalysis. We report an oxygen-induced shape transformation of rhodium nanoparticles on magnesium oxide (001) substrates that is lifted upon carbon monoxide exposure at 600 kelvin. A Wulff analysis of high-resolution in situ x-ray diffraction, combined with transmission electron microscopy, shows that this phenomenon is driven by the formation of a oxygen-rhodium-oxygen surface oxide at the rhodium nanofacets. This experimental access into the behavior of such nanoparticles during a catalytic cycle is useful for the development of improved heterogeneous catalysts.

Identification of Potato virus Y Strains Associated with Tuber Damage During a Recent Virus Outbreak in Potato in Idaho.

Potato virus Y (PVY) causes substantial losses in potato production by decreasing yields and affecting the quality of potato tubers. Management of PVY in potato is dependent primarily on potato seed certification programs to prevent or limit initial levels of virus inoculum. Prior to 1990, the ordinary strain of PVY (PVYO) was the predominant virus in North America. PVYO induces clear foliar symptoms in many potato cultivars, allowing successful management in seed potato through a combination of visual inspections and limited laboratory testing. In recent years, necrotic strains of PVY (PVYN, PVYNTN, and PVYN:O) have begun to spread in the United States, many of which induce mild symptoms in potato, making them more difficult to manage through visual inspections. In addition to reducing yield, necrotic isolates may also cause external and internal damage in tubers of susceptible cultivars, which is known as potato tuber necrotic ringspot disease (PTNRD). Tuber necrotic strains of PVY have been reported across the northern United States (1,2,4), although limited information is available on their incidence and spread in commercial potato production. During June and July of 2007, 38 random samples were collected from three different commercial fields displaying disease problems (cvs. Russet Ranger, Alturas, and Russet Burbank) in the vicinity of Idaho Falls, ID. Plants collected showed various degrees of mosaic and leaf yellowing. By using double-antibody sandwich (DAS)-ELISA and reverse transcription (RT)-PCR, 25 of these plants were identified as PVY positive. The mutiplex RT-PCR assay (3) confirmed that nine plants were infected with PVYNTN and 11 with PVYN:O. No RT-PCR products were amplified from five samples. During September and October of 2007, 25 tuber samples (cv. Russet Burbank) showing various degrees of unusual internal symptoms (e.g., brown spots) were collected near Idaho Falls, ID. Twenty-two tubers were found PVY positive by DAS-ELISA, and multiplex RT-PCR determined 13 of those were PVYNTN, three were PVYO, one was a PVYNTN/N:O mixture, and one was a PVYO/N:O mixture. No RT-PCR products were amplified from four samples. In October 2007, six tubers showing distinct external tuber damage characteristic of PTNRD (cv. Highland Russet) were collected near Twin Falls, ID. All six tubers were determined to be PVY positive by DAS-ELISA, and RT-PCR identified five as infected with PVYNTN and one with PVYN:O. All the mixtures were easily separated by inoculating tobacco plants followed by subsequent testing of individual plants. Asymptomatic tubers from the same lot not showing PTNRD damage were found PVY negative by DAS-ELISA and RT-PCR. All PVYNTN isolates collected during 2007 were inoculated into tobacco plants (Nicotiana tabacum L. cv. Xanthi) and confirmed to induce systemic vein necrosis. Limited sequencing of four of the PVYNTN isolates determined that they contained recombinant junctions 2 and 3, identifying them as being related to the European strain of PVYNTN (3). The data suggest an increase in distribution and incidence of necrotic strains of PVY in commercial, potato-production areas in Idaho during an outbreak in 2007 and the potential for an increase in PTNRD. References: (1) P. M. Baldauf et al. Plant Dis. 90:559, 2006. (2) J. M. Crosslin et al. Plant Dis. 90:1102, 2006. (3) J. H. Lorenzen et al. Plant Dis. 90:935, 2006. (4) L. M. Piche et al. Phytopathology 94:1368, 2004.

Stimulation of bone cell differentiation by low-intensity ultrasound--a histomorphometric in vitro study.

Several investigations have established a stimulatory effect of low-intensity ultrasound treatment on osteogenesis and fracture healing. The objective of this study was to examine whether the stimulatory effect of low-intensity ultrasound results in increased bone cell activity and/or proliferation. Twenty-four paired triplets of metatarsal bone rudiments of twelve 17-days-old fetal mice were dissected and divided into two groups. One group of bone rudiments was treated with pulsating low-intensity ultrasound (30 mW/cm(2); 1.5 MHz) for 20 min/day for a period of 3 or 6 days. The other group served as controls. After culture, the metatarsal bone rudiments were prepared for computer aided light microscopy. The following histomorphometric parameters were determined: length, width and volume of the calcified cartilage and of the bone collar, and cell number. GLM analysis demonstrated that bone collar volume and calcified cartilage percentage were significantly higher in the ultrasound-stimulated rudiments compared to untreated controls. Further, the calcified cartilage volume bordering the hypertrophic zone was significantly higher than in the center of the bone rudiment. Ultrasound treatment did not change the number of the cells. These results suggest that the stimulatory effect of low-intensity ultrasound on endochondral ossification is likely due to stimulation of bone cell differentiation and calcified matrix production, but not to changed cell proliferation.

Operative treatment of mid-shaft clavicular non-union.

Between 1974 and 1999, we treated operatively 28 patients with a symptomatic mid-shaft clavicular non-union using AO osteosynthesis, including bone grafting. Nine patients had a wave-plate osteosynthesis and 19 a standard AO/ASIF osteosynthesis. The mean follow-up was 10 (2-25) years. All but one non-union showed full bony consolidation. Pre-operatively, brachialgia was present in 12 patients. Of these patients, six were treated using standard osteosynthesis technique and six by wave-plate osteosynthesis. Post-operatively, patients treated by wave-plate osteosynthesis had no brachialgia and also had a higher Constant score than those patients treated using standard AO/ASIF techniques.

[Effects of low-intensity ultrasound on bone. Perspectives for dentistry?]. / Effecten van lage-intensiteit ultrageluid op bot. Perspectieven voor de tandheelkunde?

Low-intensity ultrasound is frequently used for non-invasive diagnostic purposes. However, low intensity ultrasound can also be used as a therapeutical agent. It has been concluded from animal experiments that it significantly stimulates the growth of bone. In clinical trials an accelerated healing of fracture has been found. Future research has to define the role in dentistry and the final therapeutical value of low intensity ultrasound.

Low-intensity pulsed ultrasound in the treatment of nonunions.

BACKGROUND: Low-intensity ultrasound has demonstrated an acceleration of bone healing and more profound callus formation in animal and human clinical experiments. In this study, the effect of pulsed, low-intensity ultrasound was determined in established nonunion cases. METHODS: The enrolled cases were reviewed for the time from their last surgical procedure and evidence of no healing or progression of healing during the 3 or more months before the start of low-intensity ultrasound therapy to determine whether the cases were established nonunions. Twenty-nine cases, located in the tibia, femur, radius/ulna, scaphoid, humerus, metatarsal, and clavicle, met the criteria for established nonunions. On average, the postfracture period before the start of ultrasound treatment was 61 weeks. Initial fracture treatment was conservative in 8 cases and operative in 21 cases. Additional treatments including bone grafting, reosteosynthesis, and other surgical procedures were performed an average of 52 weeks before the start of ultrasound treatment. Daily, 20-minute applications of low-intensity ultrasound at the site of the nonunion were performed by the patients at home. RESULTS: Twenty-five of the 29 nonunion cases (86%) healed in an average treatment time of 22 weeks (median, 17 weeks). Stratification of the healed and failed outcome for age, gender, concomitant disease, bone location, fracture age, prior last surgery interval, nonunion type, smoking habits, and fixation before and during treatment showed a significant difference only in the smoking habit strata. CONCLUSION: Noninvasive ultrasound therapy can be useful in the treatment of challenging, established nonunions.

Low-intensity ultrasound stimulates endochondral ossification in vitro.

Animal and clinical studies have shown an acceleration of bone healing by the application of low-intensity ultrasound. The objective of this study was to examine in vitro the influence of low-intensity ultrasound on endochondral ossification of 17-day-old fetal mouse metatarsal rudiments. Forty-six triplets of paired metatarsal rudiments were resected 'en block' and cultured for 7 days with and without low-intensity ultrasound stimulation (30 mw/cm2). At days 1, 3, 5, and 7, the total length of the metatarsal rudiments, as well as the length of the calcified diaphysis were measured. Histology of the tissue was performed to examine its vitality. The increase in length of the calcified diaphysis during 7 days of culture was significantly higher in the ultrasound-treated rudiments compared to the untreated controls (P = 0.006). The growth of the control diaphysis was 180 +/- 30 microm (mean +/- SEM), while the growth of the ultrasound-treated diaphysis was 530 +/- 120 microm. The total length of the metatarsal rudiments was not affected by ultrasound treatment. Histology revealed a healthy condition of both ultrasound-treated and control rudiments. In conclusion, low-intensity ultrasound treatment stimulated endochondral ossification of fetal mouse metatarsal rudiments. This might be due to stimulation of activity and/or differentiation of osteoblasts and hypertrophic chondrocytes. Our results support the hypothesis that low-intensity ultrasound activates ossification via a direct effect on osteoblasts and ossifying cartilage.