Comparison of thermal, rheological properties of Finnish Pinus sp. and Brazilian Eucalyptus sp. black liquors and their impact on recovery units.

Black liquor (BL) is the major bioproduct and biomass fuel in pulp mill processes. However, the high viscosity of BL makes it a challenging material to work with, resulting in issues with evaporators and heat exchangers during its transport and processing. The thermal and rheological properties of BLs from Pinus sp. (PBL) and Eucalyptus sp. (EBL) were studied. FTIR spectra revealed the presence of the characteristic functional groups and the chemical composition in liquors. TGA/DTG curves showed three characteristic degradation stages related to evaporation of water, pyrolysis of organic groups, and condensation of char. Rheologically, liquors are classified as non-Newtonian and with comportment pseudoplastic. Their rheological dynamic shear properties included a linear viscoelastic region up to 1% shear strain, while frequency sweeps showed that storage modulus (G') > loss modulus (G''), thus confirming the solid-like behavior of both BLs. The rheological study demonstrated that increasing the temperature and oscillatory deformations of PBL and EBL decreased their degree of viscoelasticity, which could favor their pumping and handling within the pulp mill, as well as the droplet formation and swelling characteristics in the recovery furnace.

Metabolomic Profiles of Nonobese and Obese Women With Gestational Diabetes.

CONTEXT: In non-pregnant population, nonobese individuals with obesity-related metabolome have increased risk for type 2 diabetes and cardiovascular diseases. The risk of these diseases is also increased after gestational diabetes. OBJECTIVE: This work aimed to examine whether nonobese (body mass index [BMI] < 30) and obese (BMI ≥ 30) women with gestational diabetes mellitus (GDM) and obese non-GDM women differ in metabolomic profiles from nonobese non-GDM controls. METHODS: Levels of 66 metabolic measures were assessed in early (median 13, IQR 12.4-13.7 gestation weeks), and across early, mid (20, 19.3-23.0), and late (28, 27.0-35.0) pregnancy blood samples in 755 pregnant women from the PREDO and RADIEL studies. The independent replication cohort comprised 490 pregnant women. RESULTS: Nonobese and obese GDM, and obese non-GDM women differed similarly from the controls across early, mid, and late pregnancy in 13 measures, including very low-density lipoprotein-related measures, and fatty acids. In 6 measures, including fatty acid (FA) ratios, glycolysis-related measures, valine, and 3-hydroxybutyrate, the differences between obese GDM women and controls were more pronounced than the differences between nonobese GDM or obese non-GDM women and controls. In 16 measures, including HDL-related measures, FA ratios, amino acids, and inflammation, differences between obese GDM or obese non-GDM women and controls were more pronounced than the differences between nonobese GDM women and controls. Most differences were evident in early pregnancy, and in the replication cohort were more often in the same direction than would be expected by chance alone. CONCLUSION: Differences between nonobese and obese GDM, or obese non-GDM women and controls in metabolomic profiles may allow detection of high-risk women for timely targeted preventive interventions.

Longitudinal Metabolic Profiling of Maternal Obesity, Gestational Diabetes, and Hypertensive Pregnancy Disorders.

CONTEXT: Comprehensive assessment of metabolism in maternal obesity and pregnancy disorders can provide information about the shared maternal-fetal milieu and give insight into both maternal long-term health and intergenerational transmission of disease burden. OBJECTIVE: To assess levels, profiles, and change in the levels of metabolic measures during pregnancies complicated by obesity, gestational diabetes (GDM), or hypertensive disorders. DESIGN, SETTING AND PARTICIPANTS: A secondary analysis of 2 study cohorts, PREDO and RADIEL, including 741 pregnant women. MAIN OUTCOME MEASURES: We assessed 225 metabolic measures by nuclear magnetic resonance in blood samples collected at median 13 [interquartile range (IQR) 12.4-13.7], 20 (IQR 19.3-23.0), and 28 (27.0-35.0) weeks of gestation. RESULTS: Across all 3 time points women with obesity [body mass index (BMI) ≥ 30kg/m2] in comparison to normal weight (BMI 18.5-24.99 kg/m2) had significantly higher levels of most very-low-density lipoprotein-related measures, many fatty and most amino acids, and more adverse metabolic profiles. The change in the levels of most metabolic measures during pregnancy was smaller in obese than in normal weight women. GDM, preeclampsia, and chronic hypertension were associated with metabolic alterations similar to obesity. The associations of obesity held after adjustment for GDM and hypertensive disorders, but many of the associations with GDM and hypertensive disorders were rendered nonsignificant after adjustment for BMI and the other pregnancy disorders. CONCLUSIONS: This study shows that the pregnancy-related metabolic change is smaller in women with obesity, who display metabolic perturbations already in early pregnancy. Metabolic alterations of obesity and pregnancy disorders resembled each other suggesting a shared metabolic origin.

Correction: Hokynar, K. et al. Chlamydia-Like Organisms (CLOs) in Finnish Ixodes ricinus Ticks and Human Skin. Microorganisms 2016, 4, 28.

The authors wish to make the following modification to this paper [...].

Chlamydia-Like Organisms (CLOs) in Finnish Ixodes ricinus Ticks and Human Skin.

Ticks carry several human pathogenic microbes including Borreliae and Flavivirus causing tick-born encephalitis. Ticks can also carry DNA of Chlamydia-like organisms (CLOs). The purpose of this study was to investigate the occurrence of CLOs in ticks and skin biopsies taken from individuals with suspected tick bite. DNA from CLOs was detected by pan-Chlamydiales-PCR in 40% of adult ticks from southwestern Finland. The estimated minimal infection rate for nymphs and larvae (studied in pools) was 6% and 2%, respectively. For the first time, we show CLO DNA also in human skin as 68% of all skin biopsies studied contained CLO DNA as determined through pan-Chlamydiales-PCR. Sequence analyses based on the 16S rRNA gene fragment indicated that the sequences detected in ticks were heterogeneous, representing various CLO families; whereas the majority of the sequences from human skin remained "unclassified Chlamydiales" and might represent a new family-level lineage. CLO sequences detected in four skin biopsies were most closely related to "uncultured Chlamydial bacterium clones from Ixodes ricinus ticks" and two of them were very similar to CLO sequences from Finnish ticks. These results suggest that CLO DNA is present in human skin; ticks carry CLOs and could potentially transmit CLOs to humans.

A Comparison of Soda Lime (Intersurgical) with Amsorb® plus: The Cost Implications

This was a prospective study comparing the cost implications between two carbon dioxide (CO2) absorbers, soda lime (Intersurgical) and AMSORB® PLUS. The study was conducted over two 4-week periods in two dedicated operating theatres using Datex Ohmeda Aestiva/5 anaesthetic machines. AMSORB® PLUS was used during the first four weeks and soda lime (Intersurgical) the following four weeks. General anaesthesia was administered as routinely done but fresh gas flow (FGF) during the maintenance phase was limited to a maximum flow of 2 L/min. The CO2 absorber was only changed when there was evidence of exhaustion. Total duration of anaesthesia, sevoflurane (bottles) and CO2 absorber (kg) consumption, and amount of waste product (kg) was calculated at the end of each study period. The total cost of delivering general anaesthesia was lower in the AMSORB® PLUS group, RM82.40 (USD19.89)/hour versus the soda lime group, RM91.50 (USD 22.09)/hour (p=0.17), which translates to a 10% reduction in cost per hour. Reduction in sevoflurane consumption in the AMSORB® PLUS compared to the soda lime group was also not statistically significant (p=0.22). The only significant finding was the reduction in CO2 absorber consumption in the AMSORB® PLUS group as compared to soda lime group (p=0.001). In conclusion, AMSORB® PLUS consumption was significantly reduced compared to that of soda lime. However, the use of AMSORB® PLUS did not significantly reduce sevoflurane consumption nor the total cost of delivering general anaesthesia. Given the superior safety profile, AMSORB® PLUS may be a suitable, cost-effective alternative to soda lime in the daily practice of anaesthesia.

Treatment of Nontraumatic Rotator Cuff Tears: A Randomized Controlled Trial with Two Years of Clinical and Imaging Follow-up.

BACKGROUND: The optimal treatment for symptomatic, nontraumatic rotator cuff tear is unknown. The purpose of this trial was to compare the effectiveness of physiotherapy, acromioplasty, and rotator cuff repair for this condition. We hypothesized that rotator cuff repair yields superior results compared with other treatment modalities. METHODS: One hundred and eighty shoulders with symptomatic, nontraumatic, supraspinatus tears were randomized into one of three cumulatively designed intervention groups: the physiotherapy-only group (denoted as Group 1), the acromioplasty and physiotherapy group (denoted as Group 2), and the rotator cuff repair, acromioplasty, and physiotherapy group (denoted as Group 3). The Constant score was the primary outcome measure. Secondary outcome measures were visual analog scale for pain, patient satisfaction, rotator cuff integrity in a control imaging investigation, and cost of treatment. RESULTS: One hundred and sixty-seven shoulders (160 patients) were available for analysis at two years. There were no significant differences (p = 0.38) in the mean change of Constant score: 18.4 points (95% confidence interval, 14.2 to 22.6 points) in Group 1, 20.5 points (95% confidence interval, 16.4 to 24.6 points) in Group 2, and 22.6 points (95% confidence interval, 18.4 to 26.8 points) in Group 3. There were no significant differences in visual analog scale for pain scores (p = 0.45) and patient satisfaction (p = 0.28) between the groups. At two years, the mean sagittal size of the tendon tear was significantly smaller (p < 0.01) in Group 3 (4.2 mm) compared with Groups 1 and 2 (11.0 mm). Rotator cuff repair and acromioplasty were significantly more expensive than physiotherapy only (p < 0.01). CONCLUSIONS: There was no significant difference in clinical outcome between the three interventions at the two-year follow-up. The potential progression of the rotator cuff tear, especially in the non-repaired treatment groups, warrants further follow-up. On the basis of our findings, conservative treatment is a reasonable option for the primary initial treatment for isolated, symptomatic, nontraumatic, supraspinatus tears in older patients. LEVEL OF EVIDENCE: Therapeutic Level I. See Instructions to Authors for a complete description of levels of evidence.

Adverse reaction to metal debris after Birmingham hip resurfacing arthroplasty.

BACKGROUND AND PURPOSE: Concern has emerged about local soft-tissue reactions after hip resurfacing arthroplasty (HRA). The Birmingham Hip Resurfacing (BHR) was the most commonly used HRA device at our institution. We assessed the prevalence and risk factors for adverse reaction to metal debris (ARMD) with this device. PATIENTS AND METHODS: From 2003 to 2011, BHR was the most commonly used HRA device at our institution, with 249 implantations. We included 32 patients (24 of them men) who were operated with a BHR HRA during the period April 2004 to March 2007 (42 hips; 31 in men). The mean age of the patients was 59 (26-77) years. These patients underwent magnetic resonance imaging (MRI), serum metal ion measurements, the Oxford hip score questionnaire, and physical examination. The prevalence of ARMD was recorded, and risk factors for ARMD were assessed using logistic regression models. The mean follow-up time was 6.7 (2.4-8.8) years. RESULTS: 6 patients had a definite ARMD (involving 9 of the 42 hips). 8 other patients (8 hips) had a probable ARMD. Thus, there was definite or probable ARMD in 17 of the 42 hips. 4 of 42 hips were revised for ARMD. Gender, bilateral metal-on-metal hip replacement and head size were not factors associated with ARMD. INTERPRETATION: We found that HRA with the Birmingham Hip Resurfacing may be more dangerous than previously believed. We advise systematic follow-up of these patients using metal ion levels, MRI/ultrasound, and patient-reported outcome measures.

Measuring short-term liver metabolism non-invasively: postprandial and post-exercise ¹H and ³¹P MR spectroscopy.

OBJECT: The objective of this study was to determine the effects of a standardized fat rich meal and subsequent exercise on liver fat content by ¹H MRS and on liver adenosine triphosphate (ATP) content by ³¹P MRS in healthy subjects. MATERIALS AND METHODS: Hepatic ¹H and proton decoupled ³¹P MRS were performed on nine healthy subjects on a clinical 3.0 T MR imager three times during a day: after (1) an overnight fast, (2) a following standardized fat rich meal and (3) a subsequent exercise session. Blood parameters were followed during the day to serve as a reference to MRS. RESULTS: Liver fat content increased gradually over the day (p = 0.0001) with an overall increase of 30 %. Also γ-NTP changed significantly over the day (p = 0.005). γ-NTP/tP decreased by 9 % (p = 0.019, post hoc) from the postprandial to the post-exercise state. CONCLUSION: Our study shows that in vivo MRS can depict short lived physiological changes; entering of fat into liver cells and consumption of ATP during exercise can be measured non-invasively in healthy subjects. The physiological state may have an impact on fat and energy metabolite levels. Hepatic ¹H and ³¹P MRS studies should be performed under standardized conditions.

Adverse reaction to metal debris after ReCap-M2A-Magnum large-diameter-head metal-on-metal total hip arthroplasty.

BACKGROUND AND PURPOSE: The clinical findings of adverse reaction to metal debris (ARMD) following large-diameter-head metal-on-metal total hip arthroplasty (LDH MoM THA) may include periarticular fluid collections, soft tissue masses, and gluteal muscle necrosis. The ReCap-M2a-Magnum LDH MoM THA was the most commonly used hip device at our institution from 2005 to 2012. We assessed the prevalence of and risk factors for ARMD with this device. METHODS: 74 patients (80 hips) had a ReCap-M2a-Magnum LDH MoM THA during the period August 2005 to December 2006. These patients were studied with hip MRI, serum chromium and cobalt ion measurements, the Oxford hip score questionnaire, and by clinical examination. The prevalence of ARMD was recorded and risk factors for ARMD were assessed using logistic regression models. The mean follow-up time was 6.0 (5.5-6.7) years. RESULTS: A revision operation due to ARMD was needed by 3 of 74 patients (3 of 80 hips). 8 additional patients (8 hips) had definite ARMD, but revision was not performed. 29 patients (32 hips) were considered to have a probable or possible ARMD. Altogether, 43 of 80 hips had a definite, probable, or possible ARMD and 34 patients (37 hips) were considered not to have ARMD. In 46 of 78 hips, MRI revealed a soft tissue mass or a collection of fluid (of any size). The symptoms clicking in the hip, local hip swelling, and a feeling of subluxation were associated with ARMD. INTERPRETATION: ARMD is common after ReCap-M2a-Magnum total hip arthroplasty, and we discourage the use of this device. Asymptomatic patients with a small fluid collection on MRI may not need instant revision surgery but must be followed up closely.

Weight-bearing CT imaging of the lower extremity.

OBJECTIVE: The purpose of this article is to describe weight-bearing CT of the lower extremity joints using a novel portable imager utilizing cone-beam CT technology. CONCLUSION: Cone-beam CT technology with new design and flexible gantry movements allows both supine and weight-bearing imaging of the lower extremities, with a reasonable radiation dose and excellent image quality. Weight-bearing CT of joints can provide important new clinical information in musculoskeletal radiology.

Comparison between the Use of LMA™ and SLIPA™ in Patients Undergoing Minor Surgeries

Supraglottic airway devices have been used as safe alternatives to endotracheal intubation in appropriate types of surgery. This was a prospective, randomised, single blind study comparing the use of LMA™ and SLIPA™ in terms of ease of insertion, haemodynamic changes and occurrence of adverse effects (e.g. blood stains on the device upon removal and sore throat). A total of 62 ASA I or II patients, aged between 18 to 70 years were recruited for this study. Patients were randomised into two groups; LMA™ and SLIPA™ group. Following induction of anaesthesia, an appropriate sized LMA™ or SLIPA™ was inserted after ensuring adequate depth of anaesthesia. Anaesthesia was maintained with oxygen, nitrous oxide and sevoflurane. The ease of insertion was graded and haemodynamic changes were recorded at 2 minute intervals up to 10 minutes after insertion of the airway devices. The presence of blood stains upon airway device removal at the end of surgery and incidence of sore throat was also recorded. No difficult insertion was experienced in either of these devices. Insertion was either easy [LMA™ 87.1% versus SLIPA™ 80.6% (p = 0.49)] or moderate [LMA™ 12.9% versus SLIPA™ 19.4% (p = 0.16)]. Throughout the study period, the haemodynamic changes that occurred in both groups were not statistically different. Traces of blood were noted on the surface of the device in 9.7% of patients in the SLIPA™ group versus 6.5% of patients in the LMA™ group. The incidence of sore throat was recorded in 12.9% versus 19.4% of patients in the SLIPA™ and the LMA™ groups respectively. These findings were not statistically significant. In conclusion, this study showed no significant differences between the use of LMA™ and SLIPA™ in terms of ease of insertion, haemodynamic changes and adverse effects in patients undergoing minor surgical procedures.

A comparison between Laryngeal Tube Suction II Airway and Proseal Laryngeal Mask Airway in laparascopic surgery.

This was a prospective randomized study comparing the ease of insertion, haemodynamic changes, quality of airway seal, oxygenation and ventilation parameters and complications between Laryngeal Tube Suction II (LTS II) with Proseal Laryngeal Mask Airway (PLMA), both are supraglottic airway incorporated with gastric passage. Fifty-four ASA I and II patients were randomly allocated to receive either LTS II or PLMA. Both devices provided a secure airway even under conditions of elevated intra-abdominal pressure up to 17 mmHg. In this study, there were no differences concerning ease of insertion, haemodynamic changes, quality of airway seal, oxygenation and ventilation parameters and complications between LTS II and PLMA.

Serum testosterone levels during early pregnancy in patients developing preeclampsia.

OBJECTIVE: The purpose of the present study was to elucidate the possible association between hyperandrogenemia and preeclampsia by analysing serum testosterone (T) in pregnant women with a specific liquid chromatography tandem mass spectrometric (LC-MS/MS) method. STUDY DESIGN: Serum levels of T, sex hormone binding globulin (SHBG) and testosterone/sex hormone binding globulin-ratio (T/SHBG-ratio) were determined during the first and second trimester in pregnancy from 91 pregnant women who later developed preeclampsia and from 182 healthy controls. RESULTS: There were no significant differences in serum T levels measured by LC-MS/MS between the patients and matched controls. The fetal gender had no influence on serum hormone levels or differences between the groups. Nor were there any significant differences in individual changes of hormones between the two sample taking periods. The results were unaffected by the matching of maternal body mass index (BMI) or other interfering factors such as parity, maternal age at the sample collection time and maternal smoking in multiple regression analyses. CONCLUSION: The concentrations of serum T, SHBG and the T/SHBG-ratio in early pregnancy do not predict the development of preeclampsia.

Factors associated with persistent risk of depression in older people following discharge from an acute cardiac unit.

BACKGROUND: This longitudinal study aims to describe the prevalence and characteristics associated with persistent risk of depression in a group of older, hospitalized patients. METHODS: We examined patients at two time-points: baseline and one month post-discharge from hospital. Patients in this study comprised those who had been admitted to the cardiology unit, with no cognitive impairment, aged 60 years and over, and those who were followed up at both time points (N = 155). Questionnaires administered included risk of depression (Geriatric Depression Scale-15; GDS-15), cognitive impairment (Mini-mental State Examination), social support (7-Item Subjective Social Support Index), co-morbidity (Charlson's Comorbidity Index), sociodemographic variables, physical functioning (Modified Barthel's Index) and clinical variables. RESULTS: The prevalence of risk of depression (GDS-15 score > or = 5) among older inpatients at baseline was 34%. At one month post-discharge this had fallen to 17% and this group was identified as those at persistent risk of depression. Factors associated with a risk of persistent depression were: hospitalization within the last six months; length of stay of four days or more; discharge diagnosis of angina; and impaired Subjective Social Support Score. CONCLUSION: Depression occurs commonly among older hospitalized patients and may resolve spontaneously. The identification of factors associated with persistent risk of depression can be helpful when looking at which patients may benefit most from screening and treatment for depression after discharge.

Fixation of experimental osteotomies with bioabsorbable SR-polylactide-polyglycolide (80/20) polymeric rods.

Self-reinforced polylactide-polyglycolide (80/20) composite rods, 2 mm in diameter and 36 mm in length, were implanted into the dorsal subcutaneous tissue of 20 rabbits. Osteotomies of the distal femur were fixed with these rods (2x15 mm) in the rabbits. The follow-up times varied from 3 to 104 weeks. After sacrifice, three-point bending and shear tests and molecular weight measurements were performed for subcutaneously placed rods. Radiological, histological, microradiographic, oxytetracycline-fluorescence, and histomorphometrical studies of the osteotomized and intact control femora were performed. After 6 weeks the mechanical properties had decreased significantly, but osteotomies had healed uneventfully. The present investigation showed that the mechanical strength and fixation properties of SR-Polylactide-glycolide (80/20) rods are suitable for fixation of cancellous bone osteotomies in rabbits provided that the operative technique is correct. The present article is the first report on the application of these rods for fixation of cancellous bone osteotomies.

The effect of low-intensity pulsed ultrasound on bone healing in SR-PLLA rod fixed experimental distal femur osteotomy in rat.

The effects of low-intensity pulsed ultrasound (30 mW/cm2) were investigated in experimental cancellous bone fracture healing in bioabsorbable self-reinforced poly-L-lactide (SR-PLLA) rod fixed distal femur osteotomy in rats. A transverse transcondylar osteotomy was fixed with one SR-PLLA rod in 32 male Wistar rats of the age of 20 weeks. Half of the rats had a daily 20-min ultrasound exposure for three weeks. The follow-up times were three, six, and 12 weeks. Radiographical, histological, microradiographical, oxytetracycline labeling, and histomorphometrical analyses were performed. No foreign-body reactions were noted. The biocompatibility of SR-PLLA and ultrasound was found to be good. In the radiological and histological assessments there was a slight tendency for enhanced healing in the ultrasound group at three weeks, but at six and 12 weeks no differences were observed. The histomorphometrical and oxytetracycline labeling analyses showed that ultrasound exposure had no significant effects on bone healing. The present study shows that there were no obvious findings to support the hypothesis that low-intensity pulsed ultrasound enhances bone healing in self-reinforced poly-L-lactide (SR-PLLA) rod fixed experimental metaphyseal distal femur osteotomy in rats. The observed good biocompatibility provides a safe starting-point for clinical trials on bioabsorbable fixation combined with low-intensity ultrasound.

Bioabsorbable screw fixation for the treatment of ankle fractures.

BACKGROUND: Self-reinforced poly(L/dL)lactide 70:30 (SR-PLA70) retains its strength in bone for 24 weeks, whereas self-reinforced poly-L-lactide (SR-PLLA) retains its strength for over 36 weeks. In this prospective randomized study, bioabsorbable 4.5-mm SR-PLA70 screws were compared with SR-PLLA screws in the treatment of displaced ankle fractures in adults. METHODS: Sixty-two patients with ankle fractures needing operative treatment were randomized into two groups. Comminuted fractures needing plating were excluded. In total 54 of 62 patients were followed up for 1 year by clinical evaluation, radiographs, and Olerud-Molander score. RESULTS: The study groups differed significantly only in the mean duration of sick leave (SR-PLA70, 60 days; SR-PLLA, 65 days; P = 0.02). At the 1-year follow-up, syndesmotic ossification was more common in the SR-PLA70 group (5 versus 1 patient, not significant). Radiologically, the screw channel had not disappeared in any of the patients by the 1-year follow-up. CONCLUSIONS: Both implant types proved to have good biocompatibility. SR-PLA70 and SR-PLLA screws are suitable in selected cases for the fixation of ankle fractures, but the mechanical stability of the fixation has to be carefully monitored perioperatively.

Bioportfolio: lifelong persistence of variant and prototypic erythrovirus DNA genomes in human tissue.

Human erythrovirus is a minute, single-stranded DNA virus causing many diseases, including erythema infectiosum, arthropathy, and fetal death. After primary infection, the viral genomes persist in solid tissues. Besides the prototype, virus type 1, two major variants (virus types 2 and 3) have been identified recently, the clinical significance and epidemiology of which are mostly unknown. We examined 523 samples of skin, synovium, tonsil, or liver (birth year range, 1913-2000), and 1,640 sera, by qualitative and quantitative molecular assays for the DNA of human erythroviruses. Virus types 1 and 2 were found in 132 (25%) and 58 (11%) tissues, respectively. DNA of virus type 1 was found in all age groups, whereas that of type 2 was strictly confined to those subjects born before 1973 (P < 0.001). Correspondingly, the sera from the past two decades contained DNA of type 1 but not type 2 or 3. Our data suggest strongly that the newly identified human erythrovirus type 2 as well as the prototype 1 circulated in Northern and Central Europe in equal frequency, more than half a century ago, whereafter type 2 disappeared from circulation. Type 3 never attained wide occurrence in this area during the past > or =70 years. The erythrovirus DNA persistence in human tissues is lifelong and represents a source of information about our past, the Bioportfolio, which, at the individual level, provides a registry of one's infectious encounters, and at the population level, a database for epidemiological and phylogenetic analyses.

Effect of ultrasound therapy on bone healing of lateral malleolar fractures of the ankle joint fixed with bioabsorbable screws.

BACKGROUND: We investigated the effect of low-intensity ultrasound on bone healing in bioabsorbable self-reinforced poly-L: -lactic acid (SR-PLLA) screw-fixed lateral malleolar fractures. The study design was prospective, randomized, double-blind, and placebo-controlled. METHODS: A total of 22 fractures were fixed with one SR-PLLA screw. All the patients were instructed to use an ultrasound device 20 min daily for 42 days without knowing whether it was active or inactive. Eleven patients had active and eleven sham ultrasound devices. The causes of error during treatment with head module placement and attachment to the convex surface of the lateral distal fibula were minimized by careful targeting and using coupling gel. Radiological fracture healing was assessed by radiographs and multidetector computed tomography (CT) scans in a blinded manner by a radiologist and orthopedic surgeons. RESULTS: The overall compliance to the daily ultrasound treatments was good. All wounds healed uneventfully, and no foreign body reactions were observed. No difference was observed between the groups regarding either fracture line visualization or callus formation assessed by plain radiographs. In the CT images at 9 weeks, the share of the endosteal united fracture line compared to the non-united fracture line was slightly higher in the active ultrasound device group than in the sham ultrasound device group, but the difference was not statistically significant. CONCLUSION: The study indicates that the biocompatibility of ultrasound therapy and bioabsorbable SR-PLLA screw fixation is good. There was no obvious effect of low-intensity ultrasound on lateral malleolar fracture healing. However, the relatively small number of patients must be kept in mind when interpreting our results. It is also important to limit any conclusions based on the present study to malleolar fractures fixed with the SR-PLLA screw.