Citrin deficiency mimicking mitochondrial depletion syndrome.

BACKGROUND: Neonatal intrahepatic cholestasis caused by citrin deficiency (CD) is a rare inborn error of metabolism due to variants in the SLC25A13 gene encoding the calcium-binding protein citrin. Citrin is an aspartate-glutamate carrier located within the inner mitochondrial membrane. CASE PRESENTATION: We report on two siblings of Romanian-Vietnamese ancestry with citrin deficiency. Patient 1 is a female who presented at age 8 weeks with cholestasis, elevated lactate levels and recurrent severe hypoglycemia. Diagnosis was made by whole exome sequencing and revealed compound heterozygosity for the frameshift variant c.852_855del, p.Met285Profs*2 and a novel deletion c.(69 + 1_70-1)_(212 + 1_231-1)del in SLC25A13. The girl responded well to dietary treatment with a lactose-free, MCT-enriched formula. Her younger brother (Patient 2) was born 1 year later and also found to be carrying the same gene variants. Dietary treatment from birth was able to completely prevent clinical manifestation until his current age of 4.5 months. CONCLUSIONS: As CD is a well-treatable disorder it should be ruled out early in the differential diagnosis of neonatal cholestasis. Due to the combination of hepatopathy, lactic acidosis and recurrent hypoglycemia the clinical presentation of CD may resemble hepatic mitochondrial depletion syndrome.

Possible mechanisms for sensorineural hearing loss and deafness in patients with propionic acidemia.

Propionic acidemia is an inborn error of metabolism caused by deficiency of the mitochondrial enzyme propionyl-CoA carboxylase. Sensorineural deafness and severe hearing loss have been described as long-term complications of this disease, however, the mechanism has not yet been elucidated. We have recently shown by patch clamping experiments and Western blots that acute and chronic effects of accumulating metabolites such as propionic acid, propionylcarnitine and methylcitrate on the KvLQT1/KCNE1 channel complex cause long QT syndrome in patients with propionic acidemia by inhibition of K+ flow via this channel. The same KvLQT1/KCNE1 channel complex is expressed in the inner ear and essential for luminal potassium secretion into the endolymphatic space. A disruption of this K+ flow results in sensorineural hearing loss or deafness. It can be assumed that acute and chronic effects of accumulating metabolites on the KvLQT1/KCNE1 channel protein may similarly cause the hearing impairment of patients with propionic acidemia.

Novel homozygous RARS2 mutation in two siblings without pontocerebellar hypoplasia - further expansion of the phenotypic spectrum.

BACKGROUND: Pontocerebellar hypoplasia type 6 (PCH6) is a mitochondrial disease caused by mutations in the RARS2 gene. RARS2 encodes mitochondrial arginyl transfer RNA synthetase, an enzyme involved in mitochondrial protein translation. A total of 27 patients from 14 families have been reported so far. Characteristic clinical features comprise neonatal lactic acidosis, severe encephalopathy, intractable seizures, feeding problems and profound developmental delay. Most patients show typical neuroradiologic abnormalities including cerebellar hypoplasia and progressive pontocerebellar atrophy. METHODS: We describe the clinical, biochemical and molecular features of 2 siblings with a novel homozygous mutation in RARS2. Both patients presented neonatally with lactic acidosis. While the older sibling had severe neurological symptoms with microcephaly, seizures and developmental delay, the younger patient was still neurologically asymptomatic at the age of 2 months. RESULTS: MRI studies in both children lacked pontocerebellar involvement. The expression of the OXPHOS complex proteins was decreased in both patients, whereas oxygen consumption was increased. CONCLUSIONS: Characteristic neuroradiological abnormalities of PCH6 such as vermis and cerebellar hypoplasia and progressive pontocerebellar atrophy may be missing in patients with RARS2 mutations. RARS2 testing should therefore also be performed in patients without pontocerebellar hypoplasia but otherwise typical clinical symptoms.

How strict is galactose restriction in adults with galactosaemia? International practice.

Dietary management of 418 adult patients with galactosaemia (from 39 centres/12 countries) was compared. All centres advised lactose restriction, 6 restricted galactose from galactosides ± fruits and vegetables and 12 offal. 38% (n=15) relaxed diet by: 1) allowing traces of lactose in manufactured foods (n=13) or 2) giving fruits, vegetables and galactosides (n=2). Only 15% (n=6) calculated dietary galactose. 32% of patients were lost to dietetic follow-up. In adult galactosaemia, there is limited diet relaxation.

Mutation analysis in 54 propionic acidemia patients.

Deficiency of propionyl CoA carboxylase (PCC), a dodecamer of alpha and beta subunits, causes inherited propionic acidemia. We have studied, at the molecular level, PCC in 54 patients from 48 families comprised of 96 independent alleles. These patients of various ethnic backgrounds came from research centers and hospitals in Germany, Austria and Switzerland. The thorough clinical characterization of these patients was described in the accompanying paper (Grünert et al. 2012). In all 54 patients, many of whom originated from consanguineous families, the entire PCCB gene was examined by genomic DNA sequencing and in 39 individuals the PCCA gene was also studied. In three patients we found mutations in both PCC genes. In addition, in many patients RT-PCR analysis of lymphoblast RNA, lymphoblast enzyme assays, and expression of new mutations in E.coli were carried out. Eight new and eight previously detected mutations were identified in the PCCA gene while 15 new and 13 previously detected mutations were found in the PCCB gene. One missense mutation, p.V288I in the PCCB gene, when expressed in E.coli, yielded 134% of control activity and was consequently classified as a polymorphism in the coding region. Numerous new intronic polymorphisms in both PCC genes were identified. This study adds a considerable amount of new molecular data to the studies of this disease.

Propionic acidemia: neonatal versus selective metabolic screening.

BACKGROUND: Whereas propionic acidemia (PA) is a target disease of newborn screening (NBS) in many countries, it is not in others. Data on the benefit of NBS for PA are sparse. STUDY DESIGN: Twenty PA patients diagnosed through NBS were compared to 35 patients diagnosed by selective metabolic screening (SMS) prompted by clinical findings, family history, or routine laboratory test results. Clinical and biochemical data of patients from 16 metabolic centers in Germany, Austria, and Switzerland were evaluated retrospectively. Additionally, assessment of the intelligent quotient (IQ) was performed. In a second step, the number of PA patients who have died within the past 20 years was estimated based on information provided by the participating metabolic centers. RESULTS: Patients diagnosed through NBS had neither a milder clinical course regarding the number of metabolic crises nor a better neurological outcome. Among NBS patients, 63% were already symptomatic at the time of diagnosis, and <10% of all patients remained asymptomatic. Among all PA patients, 76% were found to be at least mildly mentally retarded, with an IQ <69. IQ was negatively correlated with the number of metabolic decompensations, but not simply with the patients' age. Physical development was also impaired in the majority of patients. Mortality rates tended to be lower in NBS patients compared with patients diagnosed by SMS. CONCLUSION: Early diagnosis of PA through NBS seems to be associated with a lower mortality rate. However, no significant benefit could be shown for surviving patients with regard to their clinical course, including the number of metabolic crises, physical and neurocognitive development, and long-term complications.

Innovative pain therapy with a fixed combination of prolonged-release oxycodone/naloxone: a large observational study under conditions of daily practice.

BACKGROUND: Chronic pain has a marked negative impact on quality of life. Opioid treatment is often effective in controlling this pain, but it has numerous side-effects, particularly affecting bowel function. OBJECTIVE: The objective of the study was to evaluate the efficacy and safety of combined prolonged-release (PR) oxycodone and naloxone for the treatment of chronic pain under conditions of daily practice. RESEARCH DESIGN AND METHODS: This is a multi-center, prospective, non-interventional, observational study. Analgesic efficacy and bowel function were assessed in patients suffering from long-lasting, severe chronic pain of different etiology (cancer and non-cancer) treated with combined PR oxycodone/PR naloxone and observed for 4 weeks. Pain was evaluated using the Brief Pain Inventory (BPI-SF) and constipation symptoms due to opioid treatment using the Bowel Function Index (BFI). Descriptive data are presented based on observed cases, efficacy and tolerability data additionally based on completely documented patients (for each parameter at least more than 2000 patients). TRIAL REGISTRATION: This trial was registered with the German Federal Institute for Drugs and Medical Devices (BfArM), study code: OXN9002. RESULTS: A total of 7836 patients were recruited in 6496 centers. Strongest pain was reduced by an average of 2.9 points on an 11-point numeric rating scale (p < 0.001, evaluation populations n = 4271 or 2454, respectively). A progressive rise of patients without pain during the 24 hours prior to each evaluation (first visit, 11.6%; final visit, 33.8%; p < 0.001, evaluation populations n = 4413 or 3014, respectively) was observed. Bowel function improved significantly, indicated by a decrease of the bowel function index from 38.2 +/- 30.9 to 15.1 +/- 18.6 (p < 0.001, evaluation population n = 7640 or 6769, respectively) on a numeric scale of 0-100. Opioid-pretreated patients presented a marked decrease of constipation from 71% at the first visit to 34.1% at the final visit (p < 0.001, evaluation populations n = 5751 or 5123, respectively). Efficacy and tolerability were reported as good or very good by 84% and 87% of patients (evaluation populations n = 7590 and 7577, respectively). There were 4526 adverse events in 1566 patients (20.0%) with 3386 classified as adverse drug reactions; 177 patients (2.3%) suffered serious adverse events which were classified as serious adverse drug reactions in 51 cases. CONCLUSIONS: PR oxycodone/PR naloxone achieved good pain control and significantly reduced constipation and associated opioid-induced gastrointestinal symptoms in this observational 4-weeks-trial.

RNA recognition by a Staufen double-stranded RNA-binding domain.

The double-stranded RNA-binding domain (dsRBD) is a common RNA-binding motif found in many proteins involved in RNA maturation and localization. To determine how this domain recognizes RNA, we have studied the third dsRBD from Drosophila Staufen. The domain binds optimally to RNA stem-loops containing 12 uninterrupted base pairs, and we have identified the amino acids required for this interaction. By mutating these residues in a staufen transgene, we show that the RNA-binding activity of dsRBD3 is required in vivo for Staufen-dependent localization of bicoid and oskar mRNAs. Using high-resolution NMR, we have determined the structure of the complex between dsRBD3 and an RNA stem-loop. The dsRBD recognizes the shape of A-form dsRNA through interactions between conserved residues within loop 2 and the minor groove, and between loop 4 and the phosphodiester backbone across the adjacent major groove. In addition, helix alpha1 interacts with the single-stranded loop that caps the RNA helix. Interactions between helix alpha1 and single-stranded RNA may be important determinants of the specificity of dsRBD proteins.

Distinct roles of two conserved Staufen domains in oskar mRNA localization and translation.

Drosophila Staufen protein is required for the localization of oskar mRNA to the posterior of the oocyte, the anterior anchoring of bicoid mRNA and the basal localization of prospero mRNA in dividing neuroblasts. The only regions of Staufen that have been conserved throughout animal evolution are five double-stranded (ds)RNA-binding domains (dsRBDs) and a short region within an insertion that splits dsRBD2 into two halves. dsRBDs 1, 3 and 4 bind dsRNA in vitro, but dsRBDs 2 and 5 do not, although dsRBD2 does bind dsRNA when the insertion is removed. Full-length Staufen protein lacking this insertion is able to associate with oskar mRNA and activate its translation, but fails to localize the RNA to the posterior. In contrast, Staufen lacking dsRBD5 localizes oskar mRNA normally, but does not activate its translation. Thus, dsRBD2 is required for the microtubule-dependent localization of osk mRNA, and dsRBD5 for the derepression of oskar mRNA translation, once localized. Since dsRBD5 has been shown to direct the actin-dependent localization of prospero mRNA, distinct domains of Staufen mediate microtubule- and actin-based mRNA transport.

Effect of heart rate reduction by 4-(N-ethyl-N-phenyl-amino)-1,2-dimethyl-6-(methylamino)pyrimidinium chloride on infarct size in dog.

Heart rate (HR) reduction may reduce the severity of myocardial ischemia. ZD7288 (4-(N-ethyl-N-phenylamino)-1,2-dimethyl-6-(methylamino)pyrimidinium++ + chloride) is a novel bradycardic agent with a specific effect on the sinoatrial node without having any other direct effects on the heart. In the present study, the effect of ZD7288 on infarct size and regional myocardial function during regional myocardial ischemia and reperfusion was investigated. Seventeen anesthetized open chest dogs (control, n = 8, and ZD7288, n = 9) underwent 1 h of left anterior descendent artery (LAD) occlusion followed by 6 h of reperfusion. In one group, ZD7288 was given intravenously (0.7 mg/kg body weight) 45 min before LAD occlusion. Regional myocardial function was assessed by sonomicrometry as systolic wall thickening fraction (sWTF) in the anteroapical (interest region, IR) and the posterobasal wall (control region, CR). Ischemic regional myocardial blood flow (RMBF) was determined by colored microspheres and infarct size (IS) by triphenyltetrazolium staining. ZD7288 injection decreased HR from 104 +/- 5 to 74 +/- 3 bpm (mean +/- SEM, p < 0.001 vs control, vs baseline), but did not change sWTF. During reperfusion, sWTF of the IR was significantly greater in the ZD7288 group (26 +/- 12 vs -14 +/- 13%, 1 h reperfusion, p < 0.05), while sWTF of CR stayed equal (120 +/- 13 vs 111 +/- 16%, p = ns). IS was markedly reduced in the ZD7288 group (4.7 +/- 1.8 vs 18.0 +/- 5.2% of IR, p < 0.05). There was no difference in ischemic endocardial RMBF (ZD7288 11.0 +/- 4.3 vs control 12.3 +/- 6.5 ml/min/100 g, p = ns). ZD7288 reduces HR without having direct effects on regional myocardial function. This HR reduction leads to a smaller IS and to a better regional functional recovery.

Effect of acidotic blood reperfusion on reperfusion injury after coronary artery occlusion in the dog heart.

A prolongation of the intracellular acidosis after myocardial ischemia can protect the myocardium against reperfusion injury. In isolated hearts, this was achieved by prolongation of the extracellular acidosis. The aim of this study was to investigate whether regional reperfusion with acidotic blood after coronary artery occlusion can reduce infarct size and improve myocardial function in vivo. Anesthetized open-chest dogs were instrumented for measurement of regional myocardial function, assessed by sonomicrometry as systolic wall thickening (sWT). Infarct size was determined by triphenyltetrazolium staining after 3 h of reperfusion. The left anterior descending coronary artery (LAD) was perfused through a bypass from the left carotid artery. The animals underwent 1 h of LAD occlusion and subsequent bypass-reperfusion with normal blood (control, n = 6) or blood equilibrated to pH = 6.8 by using 0.1 mM HCl during the first 30 min of reperfusion (HCl, n = 5). Regional collateral blood flow (RCBF) at 30-min occlusion was measured by using colored microspheres. There was no difference in recovery of sWT in the LAD-perfused area between the two groups at the end of the experiments [-2.8+/-1.2% (HCl) vs. -4.4+/-2.5% (control); mean +/- SEM; p = NS]. RCBF was comparable in both groups. Infarct size (percentage of area at risk) was reduced in the treatment group (12.8+/-2.8%) compared with the control group (26.2+/-4.8%; p < 0.05). These results indicate that reperfusion injury after coronary artery occlusion can be reduced by a prolonged local extracellular acidosis in vivo.

[Effect of magnesium on infarct size after coronary occlusion. Animal experiment studies]. / Einfluss von Magnesium auf die Infarktgrösse nach einer Koronarokklusion. Tierexperimentalle Untersuchungen.

In addition to its antiarrhythmic and antithrombotic effects magnesium is said to have a beneficial effect in patients with acute myocardial infarction. Magnesium can protect myocardial tissue after coronary occlusion and reduces infarct size in experimental models of ischaemia and reperfusion, though the given doses of magnesium are relatively high and differ from clinically reachable serum concentrations. We tested 2 hypotheses in a dog model of ischaemia-reperfusion: 1. The protective effect may be due to a direct, local influence of magnesium on myocardial reperfusion injury. 2. Systemic magnesium treatment with low doses comparable to clinical study regiments may reduce myocardial infarct size. Anaesthetized open chest dogs underwent 1 h of left anterior descending artery occlusion followed by 6 h of reperfusion. 1. Ten animals received intracoronary magnesium aspartate (Mg i.c.) or vehicle infusion (control i.c.) for the first hour of reperfusion to increase regional Mg-concentration by 2 mmol/l. 2. Fourteen animals received intravenous infusion with magnesium potassium aspartate (Mg-K i.v.) or vehicle infusion (control i.v.), beginning 1 h before occlusion until the end of the 6 h reperfusion period. Regional magnesium concentration in the Mg i.c.-group increased to 2.7 +/- 1.00 mmol/l at 45 min of reperfusion. Intravenous infusion raised serum magnesium from 0.71 +/- 0.03 mmol/l to 1.29 +/- 0.14 mmol/l in the Mg-K i.v. group (5 min of reperfusion, p < 0.01 vs. baseline). Infarct size after 6 h reperfusion (TTC staining) was similar in both groups of intracoronary treatment (Mg i.c., 20.6 +/- 5.0; control, 24.4 +/- 8.7% of area at risk; p = n.s.) and intravenous treatment (Mg-K i.v. 18.1 +/- 14.8; control 14.1 +/- 12.2% of area at risk; p = n.s.). Neither regional nor systemic magnesium leads to a clinically relevant reduction of infarct size in the regional ischaemic-reperfused dog heart when it is given in clinically usable doses. The beneficial action of systemic Mg is probably not due to an early direct protective effect on ischaemic-reperfused myocardium but to its antiarrhythmic and antithrombotic effects. Possibly only to high doses of Mg applied under experimental conditions can reduce infarct size.

RNA localization and the development of asymmetry during Drosophila oogenesis.

Recent work on axis formation in Drosophila has revealed that polarity arises in several distinct stages during oogenesis. One cell of a germline cyst is selected to become the oocyte, the position of the oocyte determines the posterior of the follicle, and the position of the oocyte nucleus determines the dorsal side. Each of these symmetry-breaking steps involves the asymmetric localization of a unique structure, leading to polarization of the cytoskeleton and the localization of specific mRNAs.

Distribution of extracellular matrix proteins in indomethacin-induced lesions in the rat stomach.

INTRODUCTION: We investigated the distribution of extracellular matrix (ECM) proteins in indomethacin-induced lesions of the rat stomach. METHOD: Twenty rats received indomethacin orally at a dose of 8 mg/kg/body weight. The animals were killed at 3, 6, 12, 24, and 48 h after administration of the drug. The stomachs were removed and frozen in liquid nitrogen. Cryostat serial sections of the lesions were immunostained with antibodies to collagen III, IV, and VI, laminin, and fibronectin. RESULTS: Fibronectin was the dominant extracellular protein of the provisional ECM in deep gastric lesions and gastric ulcers. Collagen III was strongly positive in stromal cells under the necrotic material in gastric erosions. Basal membrane proteins (collagen IV and laminin) were found to originate from the muscularis mucosae at the ulcer edge. CONCLUSION: There is a typical distribution of ECM proteins in erosions and ulcers of the rat stomach. Fibronectin was most prominent in the provisional matrix of gastric erosions and ulcers.

NMR solution structure of a dsRNA binding domain from Drosophila staufen protein reveals homology to the N-terminal domain of ribosomal protein S5.

The double-stranded RNA binding domain (dsRBD) is an approximately 65 amino acid motif that is found in a variety of proteins that interact with double-stranded (ds) RNA, such as Escherichia coli RNase III and the dsRNA-dependent kinase, PKR. Drosophila staufen protein contains five copies of this motif, and the third of these binds dsRNA in vitro. Using multinuclear/multidimensional NMR methods, we have determined that staufen dsRBD3 forms a compact protein domain with an alpha-beta-beta-beta-alpha structure in which the two alpha-helices lie on one face of a three-stranded anti-parallel beta-sheet. This structure is very similar to that of the N-terminal domain of a prokaryotic ribosomal protein S5. Furthermore, the consensus derived from all known S5p family sequences shares several conserved residues with the dsRBD consensus sequence, indicating that the two domains share a common evolutionary origin. Using in vitro mutagenesis, we have identified several surface residues which are important for the RNA binding of the dsRBD, and these all lie on the same side of the domain. Two residues that are essential for RNA binding, F32 and K50, are also conserved in the S5 protein family, suggesting that the two domains interact with RNA in a similar way.

Intracoronary SIN-1C during reperfusion reduces infarct size in dog.

Reperfusion of ischemic myocardium may aggravate the ischemic state of injury and thus augment infarct size (reperfusion injury). The aim of this study was to reduce infarct size by an intervention at the time of reperfusion that acts only on a reperfusion-specific pathomechanism. It was investigated whether SIN-1C, a metabolite of molsidomine, can protect against reperfusion injury in canine hearts in vivo. Ten anesthetized open chest dogs underwent 1 h of left anterior descendent artery (LAD) occlusion and were randomly assigned to receive either intracoronary SIN-1C or vehicle infusion as a placebo during the first hour of reperfusion. The infusion was adjusted to LAD flow to achieve a regional blood concentration of 5 x 10(-3) M. Infarct size was assessed by triphenyltetrazolium staining after 6 h of reperfusion. Left ventricular pressure (LVP) was similar in both groups (SIN-1C: 101 +/- 6, placebo: 89 +/- 6 mm Hg, mean +/- SEM, n = 5) at the beginning of the experiment and did not change significantly thereafter from baseline values in both groups. During SIN-1C infusion, the LAD flow was increased (SIN-1C: 195 +/- 38, control: 86 +/- 17 ml/min/100 g at 30 min of reperfusion, p < 0.05), while systemic hemodynamics remained unaltered. A reduction in infarct size (percent of area at risk) was seen in the SIN-1C group (11.4 +/- 2.8%) compared with the placebo group (24.4 +/- 3.9%, p < 0.05). Infusion of papaverin (5 x 10(-5) M) following an identical protocol caused a similar vasodilation as SIN-IC, but did not reduce infarct size in five additional dox experiments.(ABSTRACT TRUNCATED AT 250 WORDS)

The immediate downstream codon strongly influences the efficiency of utilization of eukaryotic translation initiation codons.

Nucleotide substitutions were introduced into the initiation site of an influenza virus NS cDNA derivative at the +4, +5 and +6 positions (where the A of the AUG codon is defined as +1), in the background of either AUG or CUG as the initiation codon. Capped transcripts of these constructs were translated in rabbit reticulocyte lysate under conditions where the selection of initiation sites conformed to the scanning ribosome model. With CUG as the initiation codon, the efficiency of initiation was as strongly influenced by the nature of the residue in the +5 position as at +4, whilst the influence of the +6 position was smaller. The residues favourable to initiation were as follows: at +4, only G was stimulatory; at +5, A was strongly stimulatory and C fairly beneficial; and at +6, only U exerted any positive influence. The positive influence of the favourable residues (or the negative influence of unfavourable residues) at each position appeared to be additive. With AUG as the initiation codon, the pattern of response to mutations in the +4 and +5 positions was qualitatively similar, but the quantitative effects were smaller. Thus the optimum downstream context for initiation is A/CUGGAU.

Substitution mutations at the putative catalytic triad of the poliovirus 3C protease have differential effects on cleavage at different sites.

Picornavirus 3C proteases are substrate-specific cysteine proteases, proposed to be homologous to the trypsin/chymotrypsin-like serine proteases on the basis of structural predictions. Substitutions at the putative active-site residues (Glu71 and Cys147) of the poliovirus 3C protease did not completely abolish proteolytic processing in vitro. The activity of mutated 3C proteases was in the following hierarchy: Glu71-Cys147 (wild type) > Asp71-Cys147 > Glu71-Ser147 > Gln71-Cys147 > Asp71-Ser147 > Gln71-Ser147 (inactive at all sites). Such mutations had differential effects on cleavage at different sites of the poliovirus polyprotein. Cleavage within the P1 region of the polyprotein was the most defective, at the 1ABC/VP1 junction and particularly at the VP0/VP3 junction. Cleavage at the 3AB/3CD and 2B/2C junctions was less affected by the mutations, and the P2/P3 and 2A/2BC junctions were cleaved efficiently by all mutants except Gln71-Ser147. All the 3C mutants gave negative results in infectivity and replication assays after transfection, indicating that mutation of Glu71 or Cys147 virtually abolishes viral replication, irrespective of the efficiency of processing of the nonstructural part of the polyprotein.

[Roentgenologic determination of the actual femoral neck-shaft and antetorsion angle. 2: Alternatives to the Rippstein and Müller procedure]. / Die röntgenologische Bestimmung des reellen CCD- und AT-Winkels. Teil 2: Alternativen zum Verfahren nach Rippstein und Müller.

The method developed by Rippstein and Müller allows mathematically exact determination of the femoral neck-shaft angle (CCD) and the angle of torsion (AT); at a deviation of 5 degrees--10 degrees from the prescribed position of the patient considerable errors (up to more than 15 degrees) can occur. For this reason two alternative methods are cited and described in detail: cinematographic determination of the CCD and AT angle according to Schwetlick and the combination of determination of the AT angle in exterior rotation according to Rogers and an anteroposterior roentgenogram of the pelvis and hips in interior rotation of the size of the AT angle. Both methods are also mathematically exact, but, in addition almost independent from minor deviations in the positioning of the patient. It is advisable to apply one of the cited methods in cases of high AT-angle values (much greater than 30 degrees), in cases where the placing of the patient is difficult and where the determination of the angles would require major therapeutic measurement.

[Rippstein and Müller roentgenologic determination of the actual femoral neck-shaft and antetorsion angle. 1: Correction of the conversion table and study of the effects of positioning errors]. / Die röntgenologische Bestimmung des reellen CCD- und AT-Winkels nach Rippstein und Müller. Teil 1. Korrektur der Umrechnungstabelle und Untersuchung der Einflüsse von Lagerungsfehlern.

The femoral neck-shaft angle (CCD) and the angle of torsion (AT) are angles in space; in commonly used radiographs the angles are not portrayed in their actual true size (rCCD, rAT) but in their projected size, which deviates somewhat (pCCD, pAT). The formulas required for the conversion are explained in detail and the previous conversion tables have been corrected. The effects of minor deviations (5 degrees, 10 degrees and 20 degrees, increased/decreased abduction or flexion, exterior/interior rotation) from the prescribed position of the patient have been calculated and are displayed in diagrams. It is evident that determination of the angles according to Rippstein and Müller can be influenced to a considerable extend by minor discrepancies (+/- 5 degrees -10 degrees) in the positioning of the patient. If there are high AT-angle values or positioning of the patient causes problems, and where determination of the angle would involve major therapeutic measurements, another procedure will have to be used that should be almost independent from discrepancies in the positioning of the patient.