Lactate based caproate production with Clostridium drakei and process control of Acetobacterium woodii via lactate dependent in situ electrolysis.

Syngas fermentation processes with acetogens represent a promising process for the reduction of CO2 emissions alongside bulk chemical production. However, to fully realize this potential the thermodynamic limits of acetogens need to be considered when designing a fermentation process. An adjustable supply of H2 as electron donor plays a key role in autotrophic product formation. In this study an anaerobic laboratory scale continuously stirred tank reactor was equipped with an All-in-One electrode allowing for in-situ H2 generation via electrolysis. Furthermore, this system was coupled to online lactate measurements to control the co-culture of a recombinant lactate-producing Acetobacterium woodii strain and a lactate-consuming Clostridium drakei strain to produce caproate. When C. drakei was grown in batch cultivations with lactate as substrate, 1.6 g·L-1 caproate were produced. Furthermore, lactate production of the A. woodii mutant strain could manually be stopped and reinitiated by controlling the electrolysis. Applying this automated process control, lactate production of the A. woodii mutant strain could be halted to achieve a steady lactate concentration. In a co-culture experiment with the A. woodii mutant strain and the C. drakei strain, the automated process control was able to dynamically react to changing lactate concentrations and adjust H2 formation respectively. This study confirms the potential of C. drakei as medium chain fatty acid producer in a lactate-mediated, autotrophic co-cultivation with an engineered A. woodii strain. Moreover, the monitoring and control strategy presented in this study reinforces the case for autotrophically produced lactate as a transfer metabolite in defined co-cultivations for value-added chemical production.

An Examination of the Number of Adolescent Scoliotic Curves That Are Braceable at First Presentation to a Scoliosis Service.

Adolescent idiopathic scoliosis (AIS) affects between 0.5% and 5.2% of adolescents and is progressive in two-thirds of cases. Bracing is an effective non-operative treatment for AIS and has been shown to prevent up to 72% of curves from requiring surgery. This paper explores the presentation of AIS in the UK and identifies who would be suitable for bracing, as per guidelines published by the Scoliosis Research Society (SRS) and British Scoliosis Society (BSS), through curve severity and skeletal maturity at presentation. There were 526 patients with AIS eligible for inclusion across three tertiary referral centres in the UK. The study period was individualised to each centre, between January 2012 and December 2021. Only 10% were appropriate for bracing via either SRS or BSS criteria. The rest were either too old, skeletally mature or had a curve size too large to benefit. By the end of data collection, 38% had undergone surgery for their scoliosis. In the UK, bracing for AIS is only suitable for a small number at presentation. Future efforts to minimise delays in specialist review and intervention will increase the number of those with AIS suitable for bracing and reduce the number and burden of operative interventions for AIS in the UK.

Novel synthetic co-culture of Acetobacterium woodii and Clostridium drakei using CO2 and in situ generated H2 for the production of caproic acid via lactic acid.

Acetobacterium woodii is known to produce mainly acetate from CO2 and H2, but the production of higher value chemicals is desired for the bioeconomy. Using chain-elongating bacteria, synthetic co-cultures have the potential to produce longer-chained products such as caproic acid. In this study, we present first results for a successful autotrophic co-cultivation of A. woodii mutants and a Clostridium drakei wild-type strain in a stirred-tank bioreactor for the production of caproic acid from CO2 and H2 via the intermediate lactic acid. For autotrophic lactate production, a recombinant A. woodii strain with a deleted Lct-dehydrogenase complex, which is encoded by the lctBCD genes, and an inserted D-lactate dehydrogenase (LdhD) originating from Leuconostoc mesenteroides, was used. Hydrogen for the process was supplied using an All-in-One electrode for in situ water electrolysis. Lactate concentrations as high as 0.5 g L-1 were achieved with the AiO-electrode, whereas 8.1 g L-1 lactate were produced with direct H2 sparging in a stirred-tank bioreactor. Hydrogen limitation was identified in the AiO process. However, with cathode surface area enlargement or numbering-up of the electrode and on-demand hydrogen generation, this process has great potential for a true carbon-negative production of value chemicals from CO2.

Dual modality of vertebral body tethering : anterior scoliosis correction versus growth modulation with mean follow-up of five years.

AIMS: Vertebral body tethering (VBT) is a non-fusion technique to correct scoliosis. It allows correction of scoliosis through growth modulation (GM) by tethering the convex side to allow concave unrestricted growth similar to the hemiepiphysiodesis concept. The other modality is anterior scoliosis correction (ASC) where the tether is able to perform most of the correction immediately where limited growth is expected. METHODS: We conducted a retrospective analysis of clinical and radiological data of 20 patients aged between 9 and 17 years old, (with a 19 female: 1 male ratio) between January 2014 to December 2016 with a mean five-year follow-up (4 to 7). RESULTS: There were ten patients in each group with a total of 23 curves operated on. VBT-GM mean age was 12.5 years (9 to 14) with a mean Risser classification of 0.63 (0 to 2) and VBT-ASC was 14.9 years (13 to 17) with a mean Risser classification of 3.66 (3 to 5). Mean preoperative VBT-GM Cobb was 47.4° (40° to 58°) with a Fulcrum unbend of 17.4 (1° to 41°), compared to VBT-ASC 56.5° (40° to 79°) with 30.6 (2° to 69°)unbend. Postoperative VBT-GM was 20.3° and VBT-ASC Cobb angle was 11.2°. The early postoperative correction rate was 54.3% versus 81% whereas Fulcrum Bending Correction Index (FBCI) was 93.1% vs 146.6%. The last Cobb angle on radiograph at mean five years' follow-up was 19.4° (VBT-GM) and 16.5° (VBT-ASC). Patients with open triradiate cartilage (TRC) had three over-corrections. Overall, 5% of patients required fusion. This one patient alone had a over-correction, a second-stage tether release, and final conversion to fusion. CONCLUSION: We show a high success rate (95%) in helping children avoid fusion at five years post-surgery. VBT is a safe technique for correction of scoliosis in the skeletally immature patient. This is the first report at five years that shows two methods of VBT can be employed depending on the skeletal maturity of the patient: GM and ASC. Cite this article: Bone Jt Open 2022;3(2):123-129.

Dynamic Radiographs in Assessing Stability of Cervical Spine Fractures: A Multicentre Study.

BACKGROUND: In the management of a trauma patient with cervical spine injury, the need for accurate diagnostic imaging is key to ensure correct management. Different classification systems have been developed including the Subaxial Injury Classification (SLIC) system and AO cervical spine fracture classification. Through a multicentre study, we have identified a group of cases where the use of CT alone to classify fractures by either SLIC or AO score may be deficient and the use of dynamic cervical spine radiographs could help identify instability. METHODS: Three level 1 trauma centers retrospectively reviewed patients with cervical spine injuries. Cervical spine radiographs (AP and lateral) were undertaken in collar, in all patients with suspected cervical spine injury within 2 weeks, followed by reanalysis of scoring systems. RESULTS: Eleven cases were identified in total, and 72% were male with a mean age of 65 years, with approximately 54% being older than 70 years. All patients reported their pain as severe using the Visual Analogue Scale scale. The predynamic radiograph mean SLIC score was 0.73, which is in contrast to the postdynamic radiograph mean SLIC score of 6. The statistical significance (P = 0.004) was found using the Wilcoxon signed-rank test. CONCLUSION: Supine imaging eliminates the gravitational loads normally exerted on the c-spine. The cases show assumed cervical stability based on CT, but dynamic c-spine radiographs subsequently demonstrated instability. Therefore, we suggest a combination of SLIC and AO classification using radiologic imaging to classify fracture and correlate clinical symptoms with persistent neck pain, which warrants a Miami-J collar and dynamic c-spine radiograph to assess stability with re-evaluation of scoring.

Managing Known Difficult Airways in Obstetric Patients Using a Flexible Bronchoscope and IRRIS: A Case-Illustrated Guide for Nonexpert Anesthesiologists, without Surgical Backup.

Pregnancy is associated with anatomical and physiological changes leading to potential difficult airway management. Some pregnant women have known difficult airways and cannot be intubated even with a hyperangulated videolaryngoscope. If neuraxial techniques are also impossible, awake tracheal intubation with a flexible bronchoscope may be one of the few available options to avoid more invasive techniques. The Infrared Red Intubation System (IRRIS) may help nonexpert anesthesiologists in such situations and may enhance the chance of successful intubation increasing safety for the mother and the fetus, especially in hospitals without the ear, nose, and throat surgical backup.

Online survey among maritime pilots: job-related stress and strain and the effects on their work ability.

BACKGROUND: Maritime pilots often navigate ships through challenging waterways. The required 24 h standby rotation system (ROS) poses a stressful working situation. This study aims to describe the current job-related stress and strain among maritime pilots and the effects on their work ability, taking into account the different rotation systems. METHODS: Within a cross-sectional survey, pilots of all German pilots' associations were asked to complete an online questionnaire. The 1-week ROS (port pilots) was compared with the 4-month ROS (sea and canal pilots). The pilots' subjective perception of stress and strain was assessed using an established ship-specific questionnaire. Daily sleepiness and work ability were examined respectively using the Epworth Sleepiness Scale (ESS) and the Work Ability Index (WAI). RESULTS: The study group consisted of 401 male German pilots with an average age of 48.5 years (participation rate 46.9%). More than 50% of the pilots evaluated irregular working hours as the main stressor in their job. 79.8% of the pilots (especially 4-month ROS) experienced high psychological demands in their workplace. 83.3% stated having regularly neglected their private obligations due to job assignments. Pilots from the 4-month ROS experienced insufficiently predictable free time and long operation times at a stretch as stressors (p < 0.001 and p = 0.037). Elevated daily sleepiness was found in 41.9% of the pilots. The overall evaluation of the WAI questionnaire showed good to very good work ability at 77.3%. Additionally, no significant differences in the daily sleepiness or the work ability were observed between the pilots of the different two ROS. CONCLUSIONS: Due to their subjectively higher job-related mental demands, their disturbed work-life balance, and their long operation times at a stretch, it is likely that pilots from the 4-month ROS have significantly higher job stress compared to those in the 1-week ROS. However, this does not lead to more sleepiness or reduced work ability, which suggests that the pilots of this ROS are highly adapted to their working situation. Nevertheless, intervention measures with shortened ROS amongst sea and canal pilots' associations should be tested in respect of benefit, practicability and acceptance by the pilots.

A randomised controlled trial of lidocaine infusion on post-operative opioid consumption in patients undergoing robotic colorectal surgery.

INTRODUCTION: Intravenous lidocaine has been shown to have analgesic effects leading to a reduced post-operative opiate need, but this effect is still debated in various surgical populations. We investigated whether this effect could be demonstrated in robot-assisted colorectal surgery. METHODS: A total of 60 adult patients undergoing robot-assisted colorectal surgery were randomly assigned to two groups in this prospective, double-blinded trial. The lidocaine group was treated with intravenous lidocaine. Treatment was initiated before induction of anaesthesia with a bolus of 1.5 mg/kg and immediately followed by infusion of 1.5 mg/kg/h continued until 2 h after end of surgery. The control group received placebo treatment with an equal volume and a dosing of 0.9% saline. The follow-up period was 72 h. RESULTS: No significant difference between groups in the median cumulated morphine consumption at 24 and 72 h was observed. Nor were there any differences in pain score, use of antiemetics, time until flatus and/or defecation or length of hospital stay. CONCLUSIONS: In this randomised, double-blinded, prospective study using intravenous lidocaine versus 0.9% saline in robot-assisted colorectal surgery, we found no significant difference in post-operative cumulated morphine consumption at 24 or at 72 h. FUNDING: The study received funding from DASAIMs Forskningsinitiativ (2016) and DASAIMs Smerteforskningspris (2016). TRIAL REGISTRATION: The trial is registered with EudraCT (2014-003466-25) and ClinicalTrials.gov (ID: NCT03044808).

Optimising the tip-apex-distance in trochanteric femoral fracture fixation using the ADAPT-navigated technique, a longitudinal matched cohort study.

INTRODUCTION: The annual incidence of proximal femoral fractures is 100-150/100,000 and continues to increase with an aging population. Cut-out of hip screws after fracture fixation has been quoted as 8% in the literature. The tip-apex distance (TAD) is the strongest predictor for cut-out after operative fracture stabilisation. The aim of this study was to evaluate the novel ADAPT system (Adaptive Positioning Technology, Stryker, USA), a navigation device for intramedullary nailing of trochanteric fractures and its effect on optimising the TAD. This is the first clinical study to evaluate this new technology. METHODS: The study group of 36 consecutive patients with a pertrochanteric fracture underwent intramedullary nailing for fracture fixation using ADAPT technology, while the matched control group underwent conventional Gamma-3-nailing. Matching criteria included fracture classification, gender and age. We measured the operative time and the postoperative TAD in anteroposterior (AP) and lateral radiographs of the 72 patients. RESULTS: The mean TAD using ADAPT was 16.9 mm (range 8.4-33.7 mm) compared with 24.9 mm (range 14.6-40.2 mm) in the reference group treated without ADAPT. Using the ADAPT system significantly improved (p < 0.0005) the accuracy of lag screw placement but had no effect on operating time in fixation of femoral pertrochanteric fractures. CONCLUSION: Working with the novel ADAPT system for positioning the lag screw using the Gamma-3-nail led to a statistically highly significant reduction of the TAD compared to the reference group (p < 0.001). The ADAPT system proved to be a very useful device in achieving higher surgical standards for the treatment of trochanteric fractures with intramedullary nailing. It enables higher accuracy in screw positioning and therefore better placement of the implant.

Movement-Related Activity of Human Subthalamic Neurons during a Reach-to-Grasp Task.

The aim of the study was to record movement-related single unit activity (SUA) in the human subthalamic nucleus (STN) during a standardized motor task of the upper limb. We performed microrecordings from the motor region of the human STN and registered kinematic data in 12 patients with Parkinson's disease (PD) undergoing deep brain stimulation surgery (seven women, mean age 62.0 ± 4.7 years) while they intraoperatively performed visually cued reach-to-grasp movements using a grip device. SUA was analyzed offline in relation to different aspects of the movement (attention, start of the movement, movement velocity, button press) in terms of firing frequency, firing pattern, and oscillation. During the reach-to-grasp movement, 75/114 isolated subthalamic neurons exhibited movement-related activity changes. The largest proportion of single units showed modulation of firing frequency during several phases of the reach and grasp (polymodal neurons, 45/114), particularly an increase of firing rate during the reaching phase of the movement, which often correlated with movement velocity. The firing pattern (bursting, irregular, or tonic) remained unchanged during movement compared to rest. Oscillatory single unit firing activity (predominantly in the theta and beta frequency) decreased with movement onset, irrespective of oscillation frequency. This study shows for the first time specific, task-related, SUA changes during the reach-to-grasp movement in humans.

Split-belt locomotion in Parkinson's disease links asymmetry, dyscoordination and sequence effect.

BACKGROUND: The pathophysiology behind gait impairments seen in Parkinson's disease (PD), in particular freezing of gait (FOG), is not fully understood. Here we study the interplay between several gait features related to FOG during different split-belt treadmill (SBTM) conditions. METHODS: We investigated the spatiotemporal properties, the phenomenon of sequence effect and the inter-limb symmetry and temporal coordination of gait during different split-belt conditions in 20 patients with advanced Parkinson's disease and different severities of freezing. Subjects were tested in four belt configurations: tied, split while reducing the velocity of leg with the shorter (worst side reduction, WSR) and longer (best side reduction, BSR) step length, and tied again to measure the after-effect. RESULTS: We found that in spite of an improvement of spatial symmetry, the BSR led to a worsening of coordination (i.e. the left-right anti-phased stepping) and an increased sequence effect (i.e. progressive shortening of the step length). By contrast, in spite of a worsened spatial symmetry, WSR improved inter-limbs coordination and reduced the sequence effect. After prolonged split-belt walking gait was differently modulated according to the reduction of the best or worst leg velocity: BSR led to positive after effects in symmetry, bilateral coordination and sequence effect. CONCLUSIONS: These findings support the hypothesis that the irregularity of inter-limb coordination and defective amplitude generation leading to sequence effect might be coupled and result from the same maladaptive motor behavior. Furthermore, our results show that SBTM can be an effective tool to improve parkinsonian gait.

Mortality of German travellers on passenger vessels.

BACKGROUND: In the past two decades, more and more Germans decided to spend their holidays on a passenger vessel. This study examined the frequencies and causes of deaths of German travellers aboard passenger vessels of all flags. METHODS: The shipboard deaths of all German travellers within the time period from 1998 to 2008 were counted using the German civil central register in Berlin. The available documentation in this register provides information on frequencies, circumstances and causes of deaths on ships. In the above-mentioned period of time, the total cohort of German travellers on cruise ships is estimated to be 5.97 million persons. RESULTS: During the 11-year examination period, 135 shipboard deaths of German passengers [102 males (75.6%) and 33 females (24.4%)] were recorded. Out of these travellers, 110 died on cruise ships. When considering only the passengers on cruise ships (without those on ferries) an average crude mortality rate of 1.8 per 100,000 German passengers was calculated. The crude mortality rate of shipboard death for males and females was 2.5 and 0.8 per 100,000 German passengers with a mean age of 71.2 years [standard deviation (SD) 16.0 years] and 73.3 years (SD 16.0 years), respectively. Significantly, more deceased travellers older than 70 years were observed on traditional cruise ships and resort vessels than on passenger ferries (P = 0.001). The causes of death were documented in 85 cases (63.0%). Out of these documented deaths, 82 (96.5%) cases were regarded to be natural causes (particularly circulatory diseases) and 3 (3.5%) as unnatural causes (twice drowning and once an accidental fall). CONCLUSIONS: In spite of the large proportion of unknown causes of death, this study argues for a high significance of internal causes of deaths among German passengers. Thus, ship's doctors-particularly those on traditional cruise ships-should be well experienced in internal and geriatric medicines.

Production of ß-ionone by combined expression of carotenogenic and plant CCD1 genes in Saccharomyces cerevisiae.

BACKGROUND: Apocarotenoids, like the C13-norisoprenoids, are natural compounds that contribute to the flavor and/or aroma of flowers and foods. They are produced in aromatic plants-like raspberries and roses-by the enzymatic cleavage of carotenes. Due to their pleasant aroma and flavour, apocarotenoids have high commercial value for the cosmetic and food industry, but currently their production is mainly assured by chemical synthesis. In the present study, a Saccharomyces cerevisiae strain that synthesizes the apocarotenoid ß-ionone was constructed by combining integrative vectors and high copy number episomal vectors, in an engineered strain that accumulates FPP. RESULTS: Integration of an extra copy of the geranylgeranyl diphosphate synthase gene (BTS1), together with the carotenogenic genes crtYB and crtI from the ascomycete Xanthophyllomyces dendrorhous, resulted in carotenoid producing cells. The additional integration of the carotenoid cleavage dioxygenase gene from the plant Petunia hybrida (PhCCD1) let to the production of low amounts of ß-ionone (0.073 ± 0.01 mg/g DCW) and changed the color of the strain from orange to yellow. The expression of the crtYB gene from a high copy number plasmid in this former strain increased ß-ionone concentration fivefold (0.34 ± 0.06 mg/g DCW). Additionally, the episomal expression of crtYB together with the PhCCD1 gene in the same vector resulted in a final 8.5-fold increase of ß-ionone concentration (0.63 ± 0.02 mg/g DCW). Batch fermentations with this strain resulted in a final specific concentration of 1 mg/g DCW at 50 h, which represents a 15-fold increase. CONCLUSIONS: An efficient ß-ionone producing yeast platform was constructed by combining integrative and episomal constructs. By combined expression of the genes BTS1, the carotenogenic crtYB, crtI genes and the plant PhCCD1 gene-the highest ß-ionone concentration reported to date by a cell factory was achieved. This microbial cell factory represents a starting point for flavor production by a sustainable and efficient process that could replace current methods.

Subthalamic nucleus stimulation improves Parkinsonian gait via brainstem locomotor centers.

BACKGROUND: Subthalamic deep brain stimulation (STN-DBS) can ameliorate gait disturbances in Parkinson's disease (PD). Using motor imagery and positron emission tomography (PET), we investigated how STN-DBS interacts with supraspinal locomotor centers in PD. METHODS: Ten PD patients with bilateral STN-DBS actually walked or stood still under STN-DBS ON or OFF conditions. Directly thereafter, subjects imagined walking or standing while changes in regional cerebral blood flow were measured by PET. RESULTS: Independent of STN-DBS, imagined walking distance correlated with imagery duration. Compared with STN-DBS OFF, STN-DBS ON improved actual gait and increased imagined walking distance. Imagery of gait (vs. stance) induced activity in the supplementary motor area and the right superior parietal lobule for both STN-DBS conditions. The improvement of imagined gait during STN-DBS ON led to activity changes in the pedunculopontine nucleus/mesencephalic locomotor region (PPN/MLR). CONCLUSIONS: Data suggest that STN-DBS improves Parkinsonian gait by modulating PPN/MLR activity.

Physiological and anatomical decomposition of subthalamic neurostimulation effects in essential tremor.

Postural tremor is the leading symptom in essential tremor, but in some cases intention tremor and limb ataxia emerge and can become highly disabling features. Deep brain stimulation of the thalamus or subthalamic white matter improve tremor and ataxia; however, the underlying network mechanisms are enigmatic. To elucidate the mechanisms of deep brain stimulation in essential tremor, we pursued a multimodal approach combining kinematic measures of reach-to-grasp movements, clinical assessments, physiological measures of neuronal excitability and probabilistic tractography from diffusion tensor imaging. Seven patients with essential tremor (age 62.9 ± 10.3 years, two females) received thalamic deep brain stimulation and a clinical examination of severity of limb tremor and ataxia at off stimulation, using therapeutic and supratherapeutic stimulation parameters. A reach-to-grasp task based on acoustic cues was also performed. To examine the electrical properties of target structures, we determined the chronaxie of neural elements modulated. A control group of 13 healthy subjects (age 56 ± 7.6 years, five females) underwent whole-brain diffusion tensor imaging at 3 T. Probabilistic tractography was applied in healthy subjects from seeds in cerebellum and midbrain to reconstruct the connectivity pattern of the subthalamic area. The positions of stimulation electrodes in patients were transferred into probability maps and connectivity values were correlated to clinical outcome measures. Therapeutic stimulation improved ataxia and tremor mainly during the target period of the reaching paradigm (63% reduction compared with off stimulation). Notably the acceleration (29%) and deceleration periods (41%) were improved. By contrast, supratherapeutic stimulation worsened ataxia during the deceleration period with a 55% increase of spatial variability, while maintaining near complete suppression of tremor. Chronaxie measures were in the range of rapidly-conducting myelinated fibres with significantly different values for the anti-tremor effect of therapeutic stimulation (27 s) and the pro-ataxic effect of supratherapeutic stimulation (52 s). The degree of connectivity to the dentato-thalamic tract at the stimulating electrode correlated significantly with the reduction of tremor in the therapeutic condition. Our data suggest that stimulation induced tremor reduction and induction of ataxia by supratherapeutic stimulation are mediated by different fibre systems. Probalistic tractography identified the dentato-thalamic tract as a likely target of tremor suppression. Stimulation-induced ataxia may be caused by additional recruitment of adjacent fibre systems at higher amplitudes. Stimulation with short pulse duration may help to increase the therapeutic window and focus on the anti-tremor effect.

Arthroscopic-assisted hook plate fixation for acromioclavicular joint dislocation.

PURPOSE: We present a new technique of arthroscopic-assisted AC-hook plate fixation for acromioclavicular joint dislocation with all the advantages of minimally invasive surgery and the possibility to treat concomitant pathologies. METHODS: Initially a glenohumeral arthroscopy is performed to address concomitant intra-articular injuries. Under subacromial visualisation the drill hole for the hook of the plate can be exactly positioned in the acromion. The hook plate is put in place under visual control. RESULTS: The initial results (n = 3) are promising with good to excellent results in the Constant score [90.5 (range 82-100)] in all cases studied. The cross-body test was slightly positive in one case. The median follow-up time after the index procedure was seven months (range five to ten). CONCLUSIONS: In conclusion, arthroscopic-assisted reconstruction of acromioclavicular joint separation is feasible and may provide patients with all the benefits of AC-hook fixation with decreased risks related to open surgery. The described technique is recommended for all surgeons familiar with arthroscopic surgery.

Multifragmentary tibial pilon fractures: midterm results after osteosynthesis with external fixation and multiple lag screws.

Osteosynthesis of intraarticular tibial pilon fractures is preferably achieved using locking plates via a minimally invasive technique. If combined with severe soft tissue damage there is a high risk of wound-healing deficits after plate osteosynthesis. Thus our aim was to find an alternative method of treatment for those cases with combined soft tissue injuries.We report on five cases with comminuted fractures of the joint surface combined with critical soft tissue condition that were treated with lag screws and external fixation (AO) applied across the ankle joint. All five patients were followed up, undergoing clinical and radiological examination.Using this approach we achieved fracture healing of comminuted fractures without further complications. Clinical follow-up after an average of 55.6 (36-75) months revealed a mean AOFAS score of 81 (62-100).We therefore propose combined treatment using lag screws with external fixation as a practical treatment option for those fractures for which lag screws combined with a locking plate are not feasible or when there is a high risk of wound-healing deficits due to severe soft tissue damage.

Lower limb joints kinematics in essential tremor and the effect of thalamic stimulation.

Following the hypothesis that thalamic deep brain stimulation improves ataxia in patients with essential tremor by modulating the cerebello-thalamo-cortical pathway, we examined the joint kinematics of lower limbs during uninterrupted gait in eleven patients who have been treated with bilateral thalamic stimulation for 24.7±20.3 months. Patients were assessed under routine chronic stimulation, supra-therapeutic amplitude, and off stimulation by means of an infrared movement analysis system while walking on a treadmill. Chronic thalamic DBS normalized the highly variable excursion throughout the gait cycle that characterized the subgroup of patients with longest disease duration. Supratherapeutic thalamic DBS amplitude did not reproduce such improvements while, more importantly, it induced ataxic changes of joint excursion. The normalization of kinematic abnormalities argues against the hypothesis of a cerebellar neurodegeneration in ET. Moreover, these results suggest that the beneficial effect of thalamic DBS on ataxic symptoms is limited to a narrow therapeutic window.

Stimulation site within the MRI-defined STN predicts postoperative motor outcome.

High-frequency stimulation of the subthalamic nucleus (STN-HFS) is highly effective in treating motor symptoms in Parkinson's disease (PD) and medication side effects as well as in improving quality of life. Despite preoperative screening for patients as eligible candidates for this treatment, electrode position may furthermore influence treatment quality. Here, we investigated the relationship between the anatomical site of stimulation within the MRI-defined STN and the outcome of PD patients after STN-HFS. In 30 PD patients with bilateral STN stimulation, we retrospectively defined the boundaries of the STN within the axial target plane of the stereotactic T2-weighted MRI and determined the position of the active electrode contact in relation to the border of the STN. The position of the active contact within the STN was the only variable to predict the outcome of STN stimulation. In contrast, covariates such as age, disease duration, symptom severity, and response to levodopa had no effect. The lateral position of the stimulation contact within the STN led to significantly better clinical improvement, lower stimulation parameters, and less need for postoperative dopaminergic medication. The outcome of patients with stimulation contacts within the medial region of the STN was significantly worse. Precise targeting of the lateral region of the STN is essential for achieving sufficient stimulation efficacy. Preoperative T2-weighted MRI might be a useful component of the targeting procedure to improve the outcome of PD patients.