[Reconstruction of tibial metaphyseal defects with artificial components in revision arthroplasty (GenuX MK System)]. / Rekonstruktion tibialer metaphysärer Defekte im Revisionsfall mit metallischen Metaphysenkomponenten (GenuX MK-System).

OBJECTIVE: Restoration of knee function by using tibial metaphyseal components in advanced metaphyseal bone defects after multiple bone-damaging revision surgery on the knee joint. INDICATIONS: Advanced tibial metaphyseal bone defects (Anderson Orthopaedic Research Institute [AORI] IIb and III defects) in revision arthroplasty of the knee joint. CONTRAINDICATIONS: Persistent or current joint infection, general infection (e.g., pneumonia), nonreconstructable insufficient extensor apparatus. SURGICAL TECHNIQUE: Standard access including existing skin scars, arthrotomy, removal of cement spacer if necessary and removal of multiple tissue samples; preparation of femur first, followed by preparation of the tibia. Referencing the tibial rotation and joint line height. Tibial osteotomy referenced intramedullarily. Determination of the metaphyseal defect size and choice of component size. Positioning of the rasp guide for the preparation of the metaphyseal component (sleeve); gradual preparation of the bed for the metaphyseal component. Afterwards the prepared component at the desired depth (when using augments +5 or +10 mm accordingly 5 or 10 mm above the tibial plateau) is left and the tibial plateau is fixed on the embedded sleeve. Test coupling, control of the implant position and the height of the joint line radiologically. If satisfactory the definitive implants accordingly to the components of used implants before can be implanted. POSTOPERATIVE MANAGEMENT: Full weight bearing. Regular wound control; limitation of the degree of flexion only with weakened or reconstructed extensor apparatus. RESULTS: Between May 2018 and August 2019, 14 metaphyseal tibial components were implanted in 14 patients. The mean follow-up was 10.4 months. The follow-up included clinical examination, KSS (Knee Society Score) and an X­ray and failure analysis. A significant improvement in range of movement from 75 ± 16° to 100 ± 14° (p < 0.01) was achieved. The KSS improved significantly from 78 ± 12 points preoperatively to 137 ± 23 points postoperatively. Two patients complained of persistent pain after exercise (walking distance >200 m) after 6 months; tibial shaft pain was negated by all patients. The group examined afterwards showed an implant survival rate of 100% in the observation interval.

Author Correction: Rapid and Precise Semi-Automatic Axon Quantification in Human Peripheral Nerves.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Rapid and Precise Semi-Automatic Axon Quantification in Human Peripheral Nerves.

We developed a time-efficient semi-automated axon quantification method using freeware in human cranial nerve sections stained with paraphenylenediamine (PPD). It was used to analyze a total of 1238 facial and masseteric nerve biopsies. The technique was validated by comparing manual and semi-automated quantification of 129 (10.4%) randomly selected biopsies. The software-based method demonstrated a sensitivity of 94% and a specificity of 87%. Semi-automatic axon counting was significantly faster (p < 0.001) than manual counting. It took 1 hour and 47 minutes for all 129 biopsies (averaging 50 sec per biopsy, 0.04 seconds per axon). The counting process is automatic and does not need to be supervised. Manual counting took 21 hours and 6 minutes in total (average 9 minutes and 49 seconds per biopsy, 0.52 seconds per axon). Our method showed a linear correlation to the manual counts (R = 0.944 Spearman rho). Attempts have been made by several research groups to automate axonal load quantification. These methods often require specific hard- and software and are therefore only accessible to a few specialized laboratories. Our semi-automated axon quantification is precise, reliable and time-sparing using publicly available software and should be useful for an effective axon quantification in various human peripheral nerves.

Perfusion maintains functional potential in denervated mimic muscles in early persistent facial paralysis which requires early microsurgical treatment - the histoanatomic basis of the extratemporal facial nerve trunk assessing axonal load in the context of possible nerve transfers.

BACKGROUND AND OBJECTIVES: Early persistent facial paralysis is characterized by intact muscles of facial expression through maintained perfusion but lacking nerve supply. In facial reanimation procedures aiming at restoration of facial tone and dynamics, neurotization through a donor nerve is performed. Critical for reanimating target muscles is axonal capacity of both donor and recipient nerves. In cases of complete paralysis, the proximal stump of the extratemporal facial nerve trunk may be selected as a recipient site for coaptation. To further clarify the histological basis of this facial reanimation procedure we conducted a human cadaver study examining macro and micro anatomical features of the facial nerve trunk including its axonal capacity in human cadavers. Axonal loads, morphology and morbidity of different donor nerves are discussed reviewing literature in context of nerve transfers. METHODS: From 6/2015 to 9/2016 in a group of 53 fresh frozen cadavers a total of 106 facial halves were dissected. Biopsies of the extratemporal facial nerve trunk (FN) were obtained at 1 cm distal to the stylomastoid foramen. After histological processing and digitalization of 99 specimens available, 97 were selected eligible for fascicle counts and 87 fulfilled quality criteria for a semi-automated computer-based axon quantification software using ImageJ/Fiji. RESULTS: An average of 3.82 fascicles (range, 1 to 9) were noted (n = 97). 6684±1884 axons (range, 2655- 12457) were counted for the entire group (n = 87). Right facial halves showed 6364±1904 axons (n = 43). Left facial halves demonstrated 6996±1833 axons (n = 44) with no significant difference (p = 0.73). Female cadavers featured 6247±2230 (n = 22), male showed 6769±1809 axons (n = 40). No statistical difference was seen between genders (p = 0.59). A comparison with different studies in literature is made. The nerve diameter in 82 of our specimens could be measured at 1933±424 µm (range, 975 to 3012). CONCLUSIONS: No donor nerve has been described to match axonal load or fascicle number of the extratemporal facial nerve main trunk. However, the masseteric nerve may be coapted for neurotization of facial muscles with a low complication rate and good clinical outcomes. Nerve transfer is indicated from 6 months after onset of facial paralysis if no recovery of facial nerve function is seen.

Temporary epiphysiodesis using the FlexTack™ implant (tension band) featuring a modified explantation technique.

OBJECTIVE: Presenting the implantation of the PediatrOS™ FlexTack™ (Merete, Berlin, Germany) for growth guidance and a modified explantation procedure to facilitate explantation and prevent bone and soft tissue damage. INDICATIONS: Implantation: Genua vara and valga, coxa vara, varus and valgus deviation of the ankle joint, the elbow joint and the wrist Modified Explantation: Removal of the implant after successful limb correction or dislocation of the implant. CONTRAINDICATIONS: Implantation: Closed growth plates, insufficient remaining growth potential, acute or chronic infection, insufficient osseous structures, severe muscular, nervous or vessel diseases endangering the respective limb Explantation: General inoperability of the patient. SURGICAL TECHNIQUE: Implantation: Localization of the growth plate. Insertion of K­wire parallel to joint line on the joint side. Setting of the implant. Insertion of second K­wire and insertion with the implantation instrument and hammer. Modified Explantation: Cutting of the implant bridging part. Both ends of the bridging part are bent vertically to prevent soft tissue damage. Dissection of both implant arms from the bone with the chisel. Extraction in 360° motion using tooth extraction pliers. POSTOPERATIVE MANAGEMENT: Implantation: Full weight bearing. X­ray controls every 3 months to control growth correction. Explantation: Full weight bearing. RESULTS: Complications such as breaking of the k­wires, breaking of the chisel or extraction of adhering bone tissue occurred in 14 of the 64 (21.9%) explanted FlexTack implants. Complication-free removal using the original instruments provided by the manufacturer was possible for five implants. The modified explantation procedure as described above was applied in 45 explanted implants (70.3%) with complete removal of the implant without further complications within the follow up period.

The nerve supply of zygomaticus major: Variability and distinguishing zygomatic from buccal facial nerve branches.

The zygomaticus major (ZM) is important for the human smile. There are conflicting data about whether the zygomatic or buccal branches of the facial nerve are responsible for its motor innervation. The literature provides no precise distinction of the transition zone between these two branch systems. In this study, a definition to distinguish the facial nerve branches at the level of the body of the zygoma is proposed. In the light of this definition, we conducted an anatomical study to determine how the source of innervation of the ZM was distributed. A total of 96 fresh-frozen cadaveric facial halves were dissected under loupe magnification. A hemiparotidectomy was followed by antegrade microsurgical dissection. Any branch topographically lying superficial to the zygoma or touching it was classed as zygomatic, and any neighboring inferior branch was considered buccal. The arborization of the facial nerve was diffuse in all cases. In 64 out of 96 specimens (67%, 95% CI: 56% to 76%), zygomatic branches innervated the ZM. Buccal branches innervated ZM in the other 32 facial halves (33%, 95% CI: 24% to 44%). There were no differences in respect of sex or facial side. All facial halves displayed additional branches, which crossed the muscle on its inner surface without supplying it. In 31 specimens, a nerve branch ran superficial to ZM in its cranial third. According to our classification, the zygomaticus major is innervated by zygomatic branches in 67% of cases and by buccal branches in 33%. Clin. Anat. 31:560-565, 2018. © 2018 Wiley Periodicals, Inc.

The development of cerebral perfusion in healthy preterm and term neonates.

Quantitative measurement of cerebral blood flow (CBF) volume was performed by sonographic flowmetry of both internal carotid (ICA) and vertebral arteries (VA) in 113 healthy preterm and term infants of 32 - 42 weeks postmenstrual age (PA) in order to delineate the physiological characteristics of brain perfusion in a time period very sensitive to brain injury. Mean CBF volume increased with PA, beginning with 33 +/- 9 ml/min in neonates of 32 - 34 weeks and rising to 45 +/- 10, 58 +/- 13, 69 +/- 14, and 83 +/- 16 ml/min, respectively, in the PA groups of 35 - 36, 37 - 38, 39 - 40 and 41 - 42 weeks. There was no difference in CBF volume between the sexes. The bilateral sum of flow volumes in both ICA and VA rose markedly with PA. The relative contribution of bilateral VA flow volume to total CBF volume was 26 +/- 8 % and remained constant with PA. In addition, we calculated the approximate CBF (ml/100 g brain weight/min) using the brain weights of each child as estimated by means of an equation based on head circumference measurements. Estimated CBF correlated significantly with PA (r = 0.49; p

Measurement of volume of cerebral blood flow in healthy preterm and term neonates with ultrasound.

Changes in cerebral blood flow are important in the pathogenesis of ischaemic brain damage, but standard methods cannot measure volume of cerebral blood flow quantitatively in neonates. We used colour duplex sonography of the extracranial cerebral arteries to measure volume of global cerebral blood flow in 67 healthy preterm and term neonates. Volume of cerebral blood flow increased between the postmenstrual ages of 34 weeks (median 33 mL/min [range 23-43]) and 42 weeks (85 mL/min [57-104]). However, intersession and interobserver variability was quite large. This non-invasive method will allow quantitative bedside monitoring of global brain perfusion in preterm and term neonates with pathological disorders, and could also be used to monitor effects of neuroprotective measures.

Diabetes incidence in children of different nationalities: an epidemiological approach to the pathogenesis of diabetes.

AIMS/HYPOTHESIS: Incidence studies of children with Type I (insulin-dependent) diabetes mellitus and different ethnic backgrounds are known to provide important insights into the pathogenesis of the disease. For this reason, we compared the incidence rate in Baden-Württemberg, Germany, of children who were not of German descent with that of German children as well as with the reported incidence rates pertaining to the countries of origin of the children who were not of German descent. METHODS: Our study was based on the Baden-Württemberg incidence register, part of the EURODIAB TIGER network, which includes 2,121 children aged 0-14 years, diagnosed as having Type I diabetes between 1987 and 1997. The study covered a population at risk of 1.8 million children, which represents 13.3% of the total number of children in Germany. RESULTS: The total incidence rate was found to be 12.5 per 100,000 per year (95 %-CI 12.0-13.0); for German children alone it was calculated as 13.5 (95%-CI 12.9-14.1) and for children who were not of German descent it was significantly lower at 6.9 per 100,000 per year (95%-CI 5.8-8.0). The percentage of children who were not of German descent with Type I diabetes (8.3 %) is smaller than that among the general population (15.2%). Children from former Yugoslavia, Italy and Greece had incidence rates closer to their countries of origin than to the incidence rate of German children. CONCLUSION/INTERPRETATION: Our findings indicate that genetic factors play a predominant role in the pathogenesis of Type I diabetes. However, the influence of certain aspects of life-style, which remain constant even after immigration, cannot be excluded.

Varying clinical presentations at onset of type 1 diabetes mellitus in children--epidemiological evidence for different subtypes of the disease?

OBJECTIVE: On the basis of 2121 case observations between 1987 and 1997, we describe the clinical and laboratory characteristics of diabetes mellitus type 1 at its onset. Our objective is to analyze whether clinical presentation follows a uniform pattern or whether there is evidence for different subtypes. RESEARCH DESIGN AND METHODS: Thirty-one pediatric hospitals and one diabetes center in Baden-Wuerttemberg (BW), Germany, participated in this study. The hospital records of 2121 children below 15 yr of age were examined retrospectively. Statistical analysis was done after logarithmic transformation into a normal distribution. RESULTS: The average duration of symptoms was found to be 15.2 d (95% CI (Confidence Intervals) = 14.3-16.1) ranging between 2.0 and 180 d (95% central range). The most frequent symptoms were polyuria and polydipsia; 7.2% presented with altered level of consciousness. The mean blood glucose value was 407.9 mg/dL (95% CI = 400.0-416.0), corresponding to 23.3 mmol/L (95% CI = 22.8-23.8). The median pH value was 7.35 (95% CI = 7.34-7.36), and the median base excess was -5 mmol/L (95% CI =-5 to -4). The younger patients had a shorter duration of symptoms and suffered most frequently from ketoacidosis. CONCLUSIONS: Although the symptoms of diabetes at its onset follow a uniform pattern, the clinical presentation and duration of symptoms indicate that there may be various forms of type 1 diabetes.

Seasonality of birth in children (0-14 years) with diabetes mellitus type 1 in Baden-Wuerttemberg, Germany.

The aim of the study was to find out whether children with diabetes type 1 in Baden-Wuerttemberg present a pattern of seasonality in their month of birth. A cohort of 1,184 children and adolescents (0-14 years) diagnosed as having diabetes between January 1st, 1987 and June 30th, 1997 were included in the study. Monthly and seasonal patterns of birth of patients with diabetes were compared with the pattern of normal live births (n = 2,724,746) during the years 1972-1997 and the seasonality of onset of disease. Statistical analysis was made using Student's t-test to compare the means between four yearly seasons and single cosinor analysis for a period of 12 months. The children and adolescents with diabetes had a significantly different seasonality in month of birth pattern from that registered in the general population, demonstrating fewer births during the months April-June and July-September. This seasonality pattern also differs from those registered in Israel, Sardinia and Slovenia, in which the population with diabetes type 1 had most births during these months.

Incidence of IDDM in German children aged 0-14 years. A 6-year population-based study (1987-1993)

OBJECTIVE: Generally accepted data on the incidence of childhood diabetes in Germany have not been available up to now. To register the total number of newly diagnosed cases in Baden-Wuerttemberg (a federal state in southwest Germany), data on 1,160 children were retrospectively collected for the years 1987-1993. RESEARCH DESIGN AND METHODS: Hospital records were the primary data source. There were 32 hospital units in Baden-Wuerttemberg included in this study. A secondary independent data source was a questionnaire circulated among the patients' association, Deutscher Diabetiker Bund. Case definition was done according to criteria EURODIAB ACE, a collaborative European study set up to assess the incidence of childhood diabetes. The degree of ascertainment was 96.2%, using the capture-mark-recapture method. The study includes a population at risk, entailing 1.5 million children, corresponding to 12.3% of all German children. RESULTS: The incidence was found to be 11.6/100,000 (95% CI 10.9-12.2) for children aged 0-14 years. There was no significant difference between the incidence rates of boys and girls. Seasonal variation was observed, with cases increasing between November and February and incidence increasing with age. Peaks were found in early childhood (3-4 years of age) and prepuberty (10-12 years of age). There was marked geographical variation that did not correlate significantly with population density. CONCLUSIONS: For the first time, internationally comparable data on the incidence of diabetes in children up to 15 years of age are available for Germany. The yearly incidence of 11.6/100,000 proved to be much higher than assumed so far.

Use of differential DNA-repair host mediated assays to investigate the biotransformation of xenobiotics in Drosophila melanogaster. I. Genotoxic effects of nitrosamines.

A rapid differential DNA-repair assay procedure was developed to investigate the biotransformation of xenobiotics in Drosophila melanogaster in vivo. Indicator of genotoxic activity was a pair of streptomycin-dependent Escherichia coli strains differing vastly in DNA repair capacity (uvr+/rec+ vs. uvrB/recA). Prior to the experiments with test compounds, mixtures of the two strains were injected into the abdomina of untreated animal hosts (male Berlin-K flies) and the time-dependent recovery kinetics determined. Subsequently, different aliphatic and aromatic nitrosamines were tested. Solutions of the compounds were injected simultaneously with the indicator cells. Three hours later, the flies were killed, homogenized and the induction of (repairable) DNA damage determined by comparison of the survival rates of the two strains in single animals. Eight carcinogenic compounds (nitrosodiethylamine, NDEA; nitrosodimethylamine, NDMA; nitrosodi-npropylamine, NDPA; nitrosodiethanolamine, NDELA; nitrosomethylaniline, NMA; 4-methyl-nitrosopiperidine, MNPIP; nitrosopyrrolidine, NPYR; nitrosomorpholine, NMOR) and one whose tumorigenic activities are still controversially discussed (nitrosodiphenylamine, NDPhA) induced dose-dependent differential killing effects in the present system. One agent which has not been found carcinogenic in rodents (2.6-dimethyl-nitrosopiperidiine. NDMPIP) gave negative results. The ranking order of genotoxic activities of the nitrosamines found in Drosophila in vivo is in good agreement with those of carcinogenic potencies established on the basis of experiments with rats. The most pronounced exceptions are the rather weak response towards NMA and the stronger DNA damaging activity of NMPIP compared to NDMA. Phenobarbital (5-ethyl-5-phenyl-2,4,6-trioxohepatahydropyramidine) (PB) feeding of the flies resulted in an increase of the DNA damaging potencies of all nitrosamines tested. Substantial enhancement of the induction of DNA damage was however, restricted to NDEA, NPYR and NMOR, whereas with nitrosodiphenylamine (NDPhA), NDELA and NDMA only a moderate (less than 25%) increase of differential killing effects was found. In the case of the two latter compounds, these results might be due to the fact that enzymes other than the MFO are involved in their activation. Attempts to localize the formation and/or distribution of metabolites in the bodies of fruitflies by separation of the tagmata of chemically treated animals and determination of genotoxic effects in the different segments indicate that the most pronounced effects occur in the abdomina whereas in heads and thoraxes comparatively lower activities are detectable.

Measurement of the velocity of ultrasound in human cortical bone in vivo. Estimation of its potential value in the diagnosis of osteoporosis and metabolic bone disease.

Using a method combining the velocity of ultrasound and photon absorptiometry in the human radius in vivo, the authors measured the speed of sound in bone (U) and bone mineral content (BMC). From these measurements and a "simple" bone model, they then computed the bone mineral density, compact bone density, and modulus of elasticity. The accuracy of these parameters and of the bone model is assessed, and normal values for each parameter are given and compared with published values. The authors feel that a combination of U and BMC permits better discrimination between normal and abnormal in patients with osteoporosis or metabolic bone disease than either parameter alone.