Increasing grades of frontal deformities in knee osteoarthritis are not associated with ligamentous ankle instabilities.

PURPOSE: Varus or valgus deformities in knee osteoarthritis may have a crucial impact on ankle subtalar range of motion (ROM) and ligamentous stability. The purpose of this study was to assess whether the grade of ankle eversion and inversion rotation stability was influenced by frontal deformities of the knee joint. METHODS: Patients who were planned to undergo total knee arthroplasty (TKA) were prospectively included in this study. Patients were examined radiologically (mechanical tibiofemoral angle (mTFA), hindfoot alignment view angle (HAVA), anterior distal tibia angle (ADTA)) and clinically (ROM of the knee and ankle joint, foot function index, knee osteoarthritis outcome score). Ankle stability was assessed using an ankle arthrometer (AA) to test inversion/eversion (ie) rotation and anterior/posterior (ap) displacement stability of the ankle joint. Correlations were calculated using Pearson's coefficient, and differences between two independent groups of nonparametric data were calculated using a two-sided Wilcoxon signed rank test. RESULTS: Eighty-two (varus n = 52, valgus n = 30) patients were included. The preoperative mTFA significantly correlated with the HAVA (Pearson's correlation = - 0.72, p < 0.001). Laxity testing of the ankle demonstrated that in both varus and valgus knee osteoarthritis, higher grades of mTFA did not correlate with the inversion or eversion capacity of the ankle joint. The ADTA significantly correlated with the posterior displacement of the ankle joint (cor = 0.24, p = 0.049). CONCLUSIONS: This study could not confirm that higher degrees of frontal knee deformities in osteoarthritis were associated with increasing grades of ligamentous ankle instabilities or a reduced ROM of the subtalar joint. LEVEL OF EVIDENCE: II.

Accuracy of tibial positioning in the frontal plane: a prospective study comparing conventional and innovative techniques in total knee arthroplasty.

BACKGROUND: Coronal alignment of the tibial component determines functional outcome and survival in total knee arthroplasty (TKA). Innovative techniques for tibial instrumentation have been developed to improve accuracy and reduce the rate of outliers. METHODS: In a prospective study, 300 patients were allocated to four different groups using a randomization process (two innovative and two conventional) techniques of tibial instrumentation (conventional: extramedullary, intramedullary; innovative: navigation and patient-specific instrumentation (PSI); n = 75 for each group). The aims were to reconstruct the medial proximal tibial angle (MPTA) to 90° and the mechanical tibio-femoral axis (mTFA) to 0°. Both angles were evaluated and compared between all groups three months after the surgery. Patients who presented with a postoperative mTFA > 3° were classified as outliers. RESULTS: The navigation and intramedullary technique both demonstrated that they were significantly more precise in reconstructing a neutral mTFA and MPTA compared to the other two techniques. The odd's ratio (OR) for producing outliers was highest for the PSI method (PSI OR = 5.5, p < 0.05; extramedullary positioning OR = 3.7, p > 0.05; intramedullary positioning OR = 1.7, p > 0.05; navigation OR = 0.04, p < 0.05). We could only observe significant differences between pre- and postoperative MPTA in the navigation and intramedullary group. The MPTA showed a significant negative correlation with the mTFA in all groups preoperatively and in the extramedullary, intramedullary and PSI postoperatively. CONCLUSION: The navigation and intramedullary instrumentation provided the precise positioning of the tibial component. Outliers were most common within the PSI and extramedullary technique. Optimal alignment is dependent on the technique of tibial instrumentation and tibial component positioning determines the accuracy in TKA since mTFA correlated with MPTA pre- and postoperatively.

Correction of excessive intraarticular varus deformities in total knee arthroplasty is associated with deteriorated postoperative ankle function.

PURPOSE: The aim of this study was to demonstrate, whether the degree of limb alignment correction in varus knee osteoarthritis correlated with an increase in ankle symptoms and to define a cut-off value concerning the degree of correction above which to expect ankle problems. METHODS: Ninety-nine consecutive patients with preoperative intraarticular varus knee deformities who underwent total knee arthroplasty were retrospectively analyzed. Patients were examined clinically (Knee Society Score, Forgotten Joint Score, Foot Function Index, Range of Motion of the knee and ankle joint, pain scales) as well as radiologically. The mean follow-up time was 57 months. RESULTS: The degree of operative limb alignment correction strongly correlated with the Foot Function Index (R = 0.91, p < 0.05). Given this, higher degrees of knee malalignment corrections were associated with worse postoperative outcomes in the knee and ankle joint-despite postoperative improved joint line orientations. Subsequently, a cut-off value for arthritic varus deformities (14.5°) could be calculated, above which the prevalence of ankle symptoms increased manifold [OR = 15.6 (3.2-77.2 95% CI p < 0.05)]. Furthermore, ROM restrictions in the subtalar joint were associated with a worse outcome in the ankle joint. CONCLUSIONS: When correcting excessive intraarticular varus knee osteoarthritis, surgeons have to be aware of possible postoperative ankle symptoms and should consider ankle deformities or decreased subtalar ROM before operative procedures. LEVEL OF EVIDENCE: III.

The fate of Baker's cyst after total knee arthroplasty.

AIMS: It is widely held that most Baker's cysts resolve after treatment of the intra-articular knee pathology. The present study aimed to evaluate the fate of Baker's cysts and their associated symptoms after total knee arthroplasty (TKA). PATIENTS AND METHODS: In this prospective cohort study, 102 patients with (105 were included, however three were lost to follow-up) an MRI-verified Baker's cyst, primary osteoarthritis and scheduled for TKA were included. Ultrasound was performed to evaluate the existence and the gross size of the cyst before and at one year after TKA. Additionally, associated symptoms of Baker's cyst were recorded pre- and post-operatively. RESULTS: After one year, a Baker's cyst was still present in 87 patients (85%). There was a significant reduction in associated symptoms arising from the Baker's cyst before (71%) to after surgery (31%). No patients developed a new Baker's cyst associated symptoms. However, of the 72 patients who had reported Baker's cyst associated symptoms pre-operatively, 32 patients (44%) still complained of such symptoms one year after surgery. CONCLUSION: Baker's cysts had resolved in only a small number of patients (15%) one year after TKA and symptoms from the cysts persisted in 31%. Cite this article: Bone Joint J 2016;98-B:1185-8.

[The bicompartmental knee joint prosthesis Journey Deuce: failure analysis and optimization strategies]. / Die bikompartimentelle Kniegelenkendoprothese Journey Deuce: Fehlschlaganalyse und Optimierungsstrategien.

BACKGROUND: The Journey Deuce bicompartmental knee system is intended for patients with medial and patellofemoral arthritis of the knee and is aimed at diversifying the treatment options for knee arthritis. The prosthesis consists of a combined femoral shield with a medial condylar resurfacing component and a fixed bearing unicondylar tibial knee prosthesis. The advantages of the Journey Deuce system compared to total knee arthroplasty (TKA) are the bone sparing and cruciate retaining implantation. Outcome studies and investigation with respect to success and revision rates are rare. Thus the aim of this study was to investigate the early functional outcome as well as the revision and complication rates in patients with a Journey Deuce prosthesis within the first 2 years. METHODS: In this study 43 patients (25 female/18 male, average age 62.4 ± 8 years and mean body mass index27.3 ± 4.5 kg/m(2)) underwent bicompartmental knee arthroplasty using the Journey Deuce prosthesis between March 2008 and March 2009. Inclusion criteria were clinically and radiographically confirmed patellofemoral arthritis, ligament stability and flexion > 90°. Exclusion criteria were extension deficits > 5°, axis deviation > 10° and patellofemoral malalignment. Patients were followed up for 6, 12 and 24 months postoperatively. Follow-up consisted of clinical and radiographical examination as well as a survey of the Knee Society score (KSS), a pain score (visual analog scale VAS, range 0-10) and a satisfaction score. RESULTS: Of the patients 35 (82%) patients reached the 2-year follow-up and of these 35 patients 26 (75%) had a good to very good satisfaction, a mean KSS of 93 (range 65-100) and a minimal pain score of 1.2 (range 0-4). After 12 months all patients had a knee flexion of more than 90° (mean 116°, range 95°-140°). Loosening was not detected but 8 (18%) patients had to undergo revision within the first year due to persistent knee pain and instability. CONCLUSIONS: Under clear indications and exact anatomical positioning the Journey Deuce prosthesis enables a good functional outcome; however, a high revision rate occurred in this study caused by technical complexity and insufficient variety of implant sizes which led to malalignment and instability. Additional positional guidance and a higher variability in implant sizes are required to enable an adequate treatment with anatomically correct positioning. The Journey Deuce prosthesis would then be a reasonable diversification of the endoprosthesis spectrum in knee arthroplasty and would allow a more individual and selective treatment of patients with knee arthritis.

Developments of the spin labelling study of polymers at interfaces.

The spin labelling method has been used in a large variety of situations, in the broad field of polymers at solid interfaces. The relevance of the method is confirmed on linear neutral chains of poly (ethylene oxide) (PEO) in well defined situations and compared with the simple theoretical calculations of a mean field theory or some scaling arguments. Both theories have their own strengths and weaknesses. Then the fact, that polymers at solid liquid interfaces are three components systems, is considered and successively the effect of varying the polymer architecture, the solid surface and the solvent is studied. In all these cases specific results are obtained by Electron Paramagnetic Resonance (EPR) showing the usefulness and the versatility of the method.

Dynamics and conformations of PEO chains chemically bonded on silica: comparison between 1H and 2H NMR.

1H NMR was used to study the motion of monomer units in a layer of poly(ethylene oxide) chains grafted on silica. First, the dependence of the relaxation times on the grafting ratios is discussed qualitatively from a phenomenological point of view. Next, the NMR line narrowing effect by high-speed rotation is observed in the same samples with different grafting ratios. The magic angle spinning technique permits determination of two correlation times for each grafting ratio: tau(c) characteristic of an environment with a fast motion and tau(l) characteristic of an environment with a slow motion. In addition, the dynamics of these grafted chains are investigated by deuterium NMR (2H NMR), which is sensitive to the anisotropy of molecular motion. The evolution has been studied for two extreme grafting ratios and each time as a function of temperature. The anisotropy is more marked at low temperatures and for a low grafting ratio. The results are consistent with the 1H NMR relaxation times measured as a function of temperature.

Attitude of German women and gynecologists towards long-cycle treatment with oral contraceptives.

Long-cycle regimens with continuous use of oral contraceptives (OCs) for 3 or 6 months followed by a hormone-free interval of 7 days may reduce or prevent cycle-dependent and menses-related complaints. A representative survey carried out with 1195 German women in different age groups revealed that only 26-35% of the women aged between 15 and 49 years preferred monthly bleeding, while 37-46% wished to never bleed. The reasons for the refusal of regular menstruations were fewer severe menstrual complaints, better hygiene, higher quality of life, and less blood loss. Among the women who preferred regular withdrawal bleeding during the use of OCs, the main reasons were fear of pregnancy, infertility and adverse effects, and that menstruations were natural. Between 32% and 54% of the women would suppress menstruation sporadically and 11-14% for a longer period of time. After continuous treatment with a combination of 30 microg ethinyl estradiol and 2 mg dienogest for 6 months, the majority of women preferred the long-cycle regimen as compared to the conventional OC regimen despite a higher rate of irregular bleeding. Bleeding occurred primarily in first-time users of OC, particularly during the administration of the second OC pack. A survey carried out with German gynecologists revealed that most physicians prescribed extended OC cycles primarily for medical reasons, e.g., dysmenorrhea, hypermenorrhea, endometriosis and premenstrual dysphoric disorder. The gynecologists preferred a regimen with three packs of extended use of OCs.

Formation of weak polyelectrolyte multilayers studied by spin labeling.

Multilayers of alternately adsorbing poly(allylamine) (PAH) and poly(acrylic acid) (PAA) of opposite charges on silica have been studied by the spin labeling technique, as a function of pH. The two polyelectrolytes have been labeled independently by a nitroxide free radical. Its electron paramagnetic resonance spectrum is mainly sensitive to the local Brownian motion and shows lines typical of two different environments, namely, loops protruding in solution with a fast motion and trains adsorbed on the solid with a hindered motion. These two parts have been evaluated for each of the polymer layers separately, and the thickness of the coatings has been described more precisely by characterizing the four contributions existing, for example, for a bilayer. Complexation is demonstrated by the loss of loops and tails belonging to the first polyelectrolyte. The overall picture emerging from the data is explained in terms of compensation of charges and entropy of confinement.

[Acetabular component implantation in coxarthrosis due to dysplasia after high congenital hip dislocation]. / Zur Pfannenimplantation bei Dysplasiecoxarthrosen nach angeborener hoher Hüftluxation.

A total of 71 (25-110) months after primary total hip replacement, 17 patients with high congenital hip dislocation and false iliac acetabulum were clinically and radiologically assessed. Twenty-one threaded cups were placed, 16 at the site of the true acetabulum, one at the site of the acetabular rim and four at the site of the false acetabulum. The Harris hip score increased from 37.1 (20.2-55.5) points preoperatively to 84.7 (67.4-97.7) points postoperatively. Radiologically there were no signs of cup migration. It can be concluded that even complicated dysplastic hips can be treated successfully by total hip replacement, without prior ileofemoral distraction or additional acetabular augmentation.

Molecular Conformation and Mobility of Polyamines Adsorbed on Silica Studied by Spin Labeling.

Poly(ethyleneimine) and poly(4-vinylpyridine) chains adsorbed on Nucleosil silica have been randomly labeled with nitroxide free radicals. The EPR signal is very sensitive to the molecular Brownian motion of the segments and shows generally at least two different environments: trains adsorbed on the surface with a restricted mobility, and loops and tails protruding into the solution with a fast motion. The rotational correlation times and the relative fraction of each population are given as functions of the coverage achieved and of the specific surface area of the silica for the samples in contact with methanol and sometimes water. The overall picture is consistent with a diffuse layer for the PEI and a more compact one with some heterogeneities for the P4VP. Copyright 1999 Academic Press.

High-resolution 29Si solid-state NMR study of silicon functionality distribution on the surface of silicas.

29Si solid-state NMR allows us to distinguish silicon atoms involved in siloxane bridges (Q4), single silanol (Q3) and geminal silanol groups (Q2) on the surface of silica. The relative proportions of each species can be obtained by Magic Angle Spinning (MAS) associated with 1H-->29Si crosspolarization (CP/MAS). This preliminary study deals with the silicon functionality of MCM-41, a purely siliceous, amorphous and mesoporous silica. From the 29Si spectra the relative proportions are estimated to be 3.7% Q2 27.3% Q3 and 69.0% Q4, while the ratio Q2/Q2 + Q3) is 0.12. These results are found to be in perfect agreement with a binomial probability distribution of sites.

[Stress caused by sports in pregnancy]. / Sportliche Belastungen in der Schwangerschaft.

The wide adaptation range of the circulatory system, the respiratory system, and the metabolism of the female organism during pregnancy permits utilization of many positive effects of physical exercise for optimal health and wellbeing. Hitherto physically inactive pregnant women should be intensively motivated and advised, while women who are already physically active regularly should be advised to combine planned pregnancies with an optimally step-by-step reduction in training. After an uncomplicated delivery, and dependent on a normal uterus involution and lactation, a gradual adaptation to a renewed training program can be recommended. The advantages of physical exercise during pregnancy were analysed in relation to possibly dangerous complications during intensive training periods. The most important contraindications are described. The authors emphasize the increasing importance of cooperation between the Pregnancy Health Service and the Sports Medicine Service for optimal medical guidance of physically active pregnant women.

The influence of selective pancreatic denervation on plasma insulin and glucose tolerance in dogs.

The mechanism of reflex plasma insulin responses after oral stimulation and the influence of autonomic control on glucose- and meal -induced insulin secretion needs to be elucidated. Dogs with chronic pancreatic fistulas were studied two months after selective pancreatic denervation or bilateral truncal vagotomy and compared with fistulated controls. The normal glucose- and amino acid-independent insulinogenic reflex after an oral glucose load or after a meal was inhibited in the experimental groups. Glucose-related insulin secretion (oral or intravenous loads) and glucose tolerance were clearly reduced after vagotomy, but only partly diminished in the denervated animals. The plasma insulin increase after meat ingestion was inhibited in both experimental groups. It is concluded that the B-cells work under integrated tonic control of both the vagal and the sympathetic systems. Independent of this control, a vago-vagal insulinogenic reflex is initiated by enteric stimuli. These two mechanisms might be considered as part of the gastroentero-pancreatic axis in a broader sense.

[Triplet pregnancy with papyraceous foetuses (author's transl)]. / Drillingsschwangerschaft mit Fetus papyraceus.

Reported is the case of a primigravida, 22 years of age, with a triplet pregnancy. Two of the three foetuses were papyraceous. One case of this kind is related to 32,800 deliveries. An attempt was made towards aetiopathogenetic elucidation of the phenomenon.

Pancreatic and hepatic balances of endogenous insulin and of glucose in the anaesthetized dog during primed and non-primed infusions of glucose and of mannitol.

Simultaneous monitoring of pancreatic and hepatic blood flows and serial analyses of blood glucose and immunoreactive insulin activity in arterial, portal, intestinal and hepatic venous blood were performed in anaesthetized laparotomized dogs. Based on these measurements, the rates of pancreatic insulin secretion, of hepatic insulin uptake and the hepatic glucose balance were computed. Under basal conditions pancreatic output was about 40% of the total hepatic insulin input. 30% of hepatic insulin inflow were actually taken up in the liver. During a primed i.v. glucose infusion (steady blood glucose concentration about 330 mg/100 ml) pancreatic and hepatic blood flows increase rapidly and the insulin secretion exhibits a biphasic pattern. The relative part of hepatic insulin inflow taken up in the liver remained unchanged. A non-primed i.v. glucose infusion provoked a slow increase of blood flow and a rapid but monophasic increase of insulin release. Under these conditions the relative hepatic insulin uptake was transiently increased. During both loads hepatic glucose balance switched from release to uptake. However the non-primed infusion was more effective. When pancreatic and hepatic blood flows were increased without any blood glucose alteration by an infusion of mannitol, insulin secretion did not change; hepatic uptake of insulin decreased, but hepatic glucose output was clearly reduced. A correlation between the rates of insulin secretion, of hepatic insulin inflow and of insulin uptake was observed under all conditions. However, the hepatic glucose balance was correlated to the inflow of insulin or glucose and to the hepatic insulin uptake under certain conditions in individual experiments only.