Expectations and violations: Delineating the neural network of proactive inhibitory control

The ability to stop a prepared response (reactive inhibition) appears to depend on the degree to which stopping is expected (proactive inhibition). Functional MRI studies have shown that activation during proactive and reactive inhibition overlaps, suggesting that the whole neural network for reactive inhibition becomes already activated in anticipation of stopping. However, these studies measured proactive inhibition as the effect of stop‐signal probability on activation during go trials. Therefore, activation could reflect expectation of a stop‐signal (evoked by the stop‐signal probability cue), but also violation of this expectation because stop‐signals do not occur on go trials. We addressed this problem, using a stop‐signal task in which the stop‐signal probability cue and the go‐signal were separated in time. Hence, we could separate activation during the cue, reflecting expectation of the stop‐signal, from activation during the go‐signal, reflecting expectation of the stop‐signal or violation of that expectation. During the cue, the striatum, the supplementary motor complex (SMC), and the midbrain activated. During the go‐signal, the right inferior parietal cortex (IPC) and the right inferior frontal cortex (IFC) activated. These findings suggest that the neural network previously associated with proactive inhibition can be subdivided into two components. One component, including the striatum, the SMC, and the midbrain, activated during the cue, implicating this network in proactive inhibition. Another component, consisting of the right IPC and the right IFC, activated during the go‐signal. Rather than being involved in proactive inhibition, this network appears to be involved in processes associated with violation of expectations. Hum Brain Mapp 34:2015–2024, 2013. © 2011 Wiley Periodicals, Inc.     

Neuropsychological evidence for a dissociation in counting and subitizing

There is a long and ongoing debate about whether subitizing and counting are separable processes. In the present paper we report a single case, MH, who presents with a dissociation in subitizing and counting. MH was spared in his ability to enumerate small numbers accurately along with a marked inability to count larger numbers. We show that non-visual counting was intact and visual counting improved when a motor record of counting could be maintained. Moreover, when larger numbers of items were spatially grouped into 2 subitizable units, performance dramatically improved. However, color grouping did not aid MH's performance, despite his being sensitive to color segmentation. In addition, MH made more re-visits of inspected locations than controls, and he was less aware of a re-visitation being made. The data cannot be explained in terms of general working memory problems (verbal working memory was relatively spared), or general number comprehension problems (e.g., simple sums and counting of auditory items was intact); but they can parsimoniously be accounted for in terms of impaired visuo-spatial memory. The findings support the argument that at least some processes are specific to counting and are not required for subitization – in particular spatial coding and memory for previously inspected locations.     

Randomized Controlled Trial to Compare Two Bone Substitutes in the Treatment of Bony Dehiscences

Aim: This in vivo split‐mouth randomized controlled trial compared a synthetic bone substitute with a bovine bone mineral to cover bone dehiscences after implant insertion. Materials and Methods: Fourteen patients received four to six implants to support an overdenture. Two comparable dehiscences within the same patient were first covered with a layer of autogenous bone, followed by a layer of either Bio‐Oss® (group 1; Geistlich Pharma AG, Wolhusen, Switzerland) or Straumann BoneCeramic® (group 2; Institut Straumann AG, Basel, Switzerland) and sealed by a resorbable membrane. The change in vertical dimension of the defect was measured at implant placement and at abutment connection (6.5 months). Clinical and radiological parameters were evaluated up to 1 year of loading. Results: The vertical size of the defect at surgery was 6.4 ± 1.6 mm for group 1 and 6.4 ± 2.2 mm for group 2 sites, measured from the implant shoulder. After 6.5 months, the depth of the defect was reduced to 1.5 ± 1.2 mm and 1.9 ± 1.2 mm for group 1 and group 2 sites, respectively (p > 0.05). No implants failed during follow‐up. Mean marginal bone loss over the SLActive surface was 0.94 mm (group 1), 0.81 mm (group 2), and 0.93 mm (group 3, no dehiscence) after 1 year of loading. Conclusion: Both bone substitutes behaved equally effectively.     

The association between insulin-like growth factor-I and cardiac repolarization

ObjectivePrevious studies reported associations between insulin-like growth factor I (IGF-I) serum concentration and cardiac morbidity and mortality, but the association between IGF-I serum concentration and cardiac repolarization has not been investigated in a population-based study so far. Therefore, we analyzed the impact of IGF-I concentrations on QTc, QT and RR intervals in two population based studies, The Study of Health in Pomerania (SHIP) and the Rotterdam Study.Design457 individuals from SHIP and 155 individuals from the Rotterdam Study older than 55 years and without cardiovascular diseases and a left ventricular hypertrophy were investigated. IGF-I was determined by automated two-site chemiluminescence immunoassays and electrocardiograms were recorded by an ACTA electrocardiograph at a sampling frequency of 500 Hz. The association of IGF-I with QTc, QT and RR intervals was investigated by multivariable linear regression analyses adjusted for age, gender, diabetes mellitus, myocardial infarction, hypertension, body mass index, serum potassium and calcium in both studies separately and in pooled analysis.ResultsThere were no significant associations between log-transformed IGF-I and QTc interval in the single populations, whereas a significant inverse association was detectable in the pooled population (β, ? 15.6; 95%-confidence interval, ? 25.7, ? 5.5). The QTc interval was significantly higher in the first tertile of IGF-I compared to the third tertile (β, 5.4; 95%-confidence interval, 9.5–1.3) in the pooled analysis.ConclusionThe inverse association between IGF-I serum concentrations and QTc interval in our study is suggestive of a higher risk for cardiac arrhythmias and thus might provide additional evidence for increased cardiovascular mortality in subjects with low IGF-I secretion.     

Adipose Tissue as Regulator of Vascular Tone

Adipokines secreted by visceral, subcutaneous, and perivascular adipocytes are involved in the regulation of vascular tone by acting as circulatory hormones (leptin, adiponectin, omentin, visfatin, angiotensin II, resistin, tumor necrosis factor-α, interleukin-6, apelin) and/or via local paracrine factors (perivascular adipocyte-derived relaxing and contractile factors). Vascular tone regulation by adipokines is compromised in obesitas and obesity-related disorders. Hypoxia created in growing adipose tissue dysregulates synthesis of vasoactive adipokines in favor of harmful proinflammatory adipokines, while the levels of the cardioprotective adipokines adiponectin and omentin decrease. Considering the potential of the role of adipokines in obesity-related vascular diseases, strategies to counter these diseases by targeting the adipokines are discussed.     

Solvent-assisted linker exchange as a tool for the design of mixed-linker MIL-140D structured MOFs for highly selective detection of gaseous H2S

A MIL-140D-sdc framework has been used as a highly stable backbone for the introduction of 4,4′-azobenzene dicarboxylic acid (H₂abdc) via solvent-assisted ligand exchange (SALE). The implemented azo groups can serve as coordination sites for copper ions. These can exchange ligands with different gases, but show a high selectivity against H₂S, which makes this material promising for potential sensor applications.

Solvent-assisted linker exchange was used as tool to modify a MIL-140D-sdc (sdc = 4,4′-stilbenedicarboxylate) MOF with azostilbene dicarboxylic acid. The azo groups can act as coordination sites for copper ions and allow the use of this material as sensor for gaseous H₂S.

Hydrogen sulfide (H₂S) is a toxic gas with harmful effects on human health and is responsible for different diseases, like liver cirrhosis.¹ At concentrations above just 50 ppm, irritation of the respiratory tract can occur.² For the detection of H₂S, chemical sensors containing semiconducting metal oxides are widely used. Although these exhibit high sensitivities, they also have some disadvantages due to their high working temperatures and a lack of selectivity.³Especially in the areas of selectivity and cross-sensitivity, metal–organic frameworks (MOFs) can overcome the limits that plague many other sensors. Due to their modular design built up by metal nodes and organic linker molecules, they can be tailored to the desired application.⁴ Functionalities attached to the linkers of MOFs are often required in order to be able to use these materials for sensor applications.⁵Many MOFs are described for the detection of H₂S. Apart from one example of a capacitive sensor,⁶ the detection is almost always based on a fluorescence turn-on probe. Here functional groups of the MOF (–N₃ or –NO₂) are reduced by H₂S to amino groups resulting in turning on the fluorescence of the linker. However, in these investigations the MOFs are dispersed in buffered aqueous or ethanolic solutions.⁷ In addition, no gaseous H₂S is used, but sulfides-containing sodium salts such as Na₂S, that dissociate in solution to HS⁻, which is required for the reaction.⁸ To the best of our knowledge, only one example is described in literature where a MOF is used for a luminescent-based detection of gaseous H₂S.⁹Azo components have the special ability to coordinate metal ions. This has already been investigated in detail with individual azo compounds and metal salts of palladium¹⁰ or copper.^11,12 Until now, a transfer of this reaction behaviour into a MOF is rare and not yet described for copper species but for palladium species.¹³ Nevertheless, these copper-azo complexes can be used for the colourimetric detection of both aqueous HS⁻ and gaseous H₂S.¹⁴ The sensor principle is based on a displacement reaction. The coordinated copper ions react with gaseous H₂S to CuS as already shown with CuO-loaded metal oxide semiconductors.¹⁵ Considering copper-based MOFs such as the HKUST-1, they show a lack of stability under normal conditions, making them unsuitable for use in sensor technology. Nevertheless, a reaction between H₂S and the metal centres is still possible, however, this leads to the formation of CuS and the complete breakdown of the framework.¹⁶With the UiO family, a isoreticular series of Zr-based MOFs was reported.¹⁷ Particularly, the UiO-66 and its derivatives exhibit an exceptional thermal and chemical stability. By the use of the same precursors but higher synthesis temperatures, Guillerm et al. presented highly stable Zr-MOFs, the so-called MIL-140 series.¹⁸ In MIL-140 frameworks, there are one-dimensional chains of zirconium oxide (c.n. 7) as inorganic building units (IBUs) orientated parallel to the c-axis of the structures. Each chain is connected via linker molecules to six other chains resulting in a one-dimensional pore system (see ESI Fig. S1^†). Especially those MOFs with longer linker molecules exhibit an improved stability in comparison to their UiO analogues. This can be explained with the different structures of these compounds.^18,19By using post-synthetic modifications (PSM) further functionalized MOF materials can be obtained.²⁰ In case of exchanging an unfunctionalized linker molecule with a functionalized, the solvent-assisted ligand exchange (SALE) is an attractive possibility to adjust the properties of an already synthesized MOF and enhance the tunability.²¹We recently reported a low-temperature synthesis of MIL-140 frameworks and a new MIL-140-structured MOF, based on 4,4′-stilbenedicarboxylic acid (H₂sdc), the MIL-140D-sdc (see Table S1 and ESI Fig. S1^†).²² This MOF shows a high thermal and chemical stability which can be compared to the former reported MIL-140 MOFs.¹⁸ A synthesis for an azo-based MIL-140D-H with H₂abdc as linker is also described in literature (see ESI Table S1^†).²³ However, the resulting framework is instable under ambient conditions and a transition to a unknown nearly nonporous phase occurs after only a few days.²³ These are unfavourable properties for a stable sensor material.In this work, we demonstrate the efficiency of the SALE to produce MOFs that combine high stability and high functionality. Therefore, we use the MIL-140D-sdc framework as stable backbone. For the preparation of the mixed-linker MOF (MIL-140D-sdc/abdc), we substitute sdc²⁻ with abdc²⁻via SALE by immersing the MIL-140D-sdc in a DMF solution of H₂abdc and storing it at 120 °C for 24 h (up to 1 eq. H₂abdc with respect to the Zr cations in the framework, see ESI Table S2^†).For verifying the successful SALE, the exchanged MOF samples were disassembled and analysed with ¹H-NMR spectroscopy (ESI Fig. S2 and S3^†). The evaluation has shown that the level of conversion rises with an increasing amount of provided linkers (H₂abdc). The maximum exchange rate is slightly below 50%.Powder X-ray diffraction (PXRD) is used to check the stability of the compounds after each reaction step. After exchanging the MIL-140D-sdc with abdc²⁻ at 120 °C, the solids exhibit the same diffraction pattern, but the colour has changed from white to reddish (Fig. 1a).Open in a separate windowFig. 1Presentation of the conducted modification, incorporation and gas exposure with MIL-140D-sdc structured MOFs. (a) Powder XRD pattern of the samples prepared with a SALE starting from MIL-140D-sdc and the resulting colour change with different amounts of H₂abdc. (b) Powder XRD pattern after the incorporation of increasing amounts of Cu²⁺ into the MIL-140D-sdc/abdc framework and the observed colour change and (c) powder XRD pattern and pictures of the same materials after the exposure to 100 ppm H₂S.The advantage of MIL-140 structured MOFs results from the stacking of the linkers and the resulting short distance between the azo groups. This arrangement should be promising for the coordination of copper ions, since in literature the molecules either have additional functional groups for the coordination or the metal ions are located between two azo groups.²⁴ Subsequently, copper ions are incorporated into the framework. For this purpose, the linker-exchanged MOF is dispersed in DMF and stirred for 1 hour at room temperature while adding copper chloride. The amount of copper chloride used is identical to the previously used amount of added linker H₂abdc (see ESI Table S3^†). After the copper ions were integrated into the framework, the colour of the MOF changed from red to green (Fig. 1b). Although the samples still show the same diffraction pattern, a closer look reveals differences. Thus, the 200-reflection (at 5° 2Θ) shifts slightly to smaller angles and in the range of 10° 2Θ the intensity of two reflections increase (ESI Fig. S4^†). Neither the shifted reflection nor the colour change can be observed during the treatment of UiO-abdc and MIL-140D-H with copper chloride. Additionally, pure MIL-140D-H appears not to be stable during this reaction (ESI Fig. S5 and S6^†).Nitrogen physisorption measurements verified that there is no significant quantity of linker molecules in the tunnel-like pores after the SALE (ESI Fig. S12 and Table S5^†). In order to demonstrate that the integrated copper ions do not inhibit the accessibility of the pores, N₂ physisorption measurements have been repeated (ESI Fig. S13^†). Indeed, the experimental BET areas barely change and are only about 100 m² g⁻¹ lower (ESI Table S6^†). It can therefore be assumed that the copper ions are coordinated at the azo groups of the linkers and thus hardly contribute to a loss of surface area.For further simplification, at this point the focus is on the samples with the highest exchanged amount of linker and highest stored quantity of Cu²⁺ (1 eq. each). For a more detailed evaluation of the pore size and thus the location of the incorporated copper ions, argon physisorption measurements were carried out. Compared to the originally used sample MIL-140D-sdc, the BET areas are only slightly reduced and also the calculated pore size distributions for all samples show a good correlation (Fig. S15, S16 and Table S8^†). Both measurements indicate a coordination of the copper ions at the azo groups of the linkers. Furthermore, this result contradicts an excessive adsorption of the copper ions in the tunnel-like pores.The amount of copper coordinated in the MOF is estimated by EDX spectroscopy. For this purpose, the MOF was offered two different quantities of copper salt (0.5 and 1.0 eq.) for complexation. In comparison to the SALE sample, the EDX measurements show the same copper content of 0.4 copper atoms per sum formula, regardless of whether 0.5 or 1.0 eq. copper salt was added (see ESI Fig. S17–S19 and Table S9^†). The similar value is due to the fact that only half of the linkers are exchanged during the SALE and again suggests the coordination of the copper ions at the azo groups.The thermogravimetric data are a further indication for the successful storage of Cu²⁺ in the framework. The sample obtained after the SALE shows a similar thermal decomposition as the starting material MIL-140D-sdc. Both materials have a thermal stability of about 350 °C, but the residual mass is lower than calculated in case of the SALE sample (ESI Fig. S21 and Table S10^†). After incorporation, the residual mass increases by approximately 4.5m%, which is equivalent to a copper amount of approximately 0.45 per sum formula and in good agreement with the EDX spectroscopy. The reflections of the powder diffraction pattern of the residue can be accurately assigned to ZrO₂ and CuO (see ESI Fig. S7^†). In addition, the percentage of guests in the framework is increasing drastically. This could be an indication that the copper ions act as Lewis acidic sites where solvent molecules preferentially coordinate. In order to estimate the Lewis acidity of a MOF, the shift of the acetone absorption band can be considered.²⁵ In the presence of strongly Lewis-acidic MOFs, the stretching vibration of the carbonyl group shifts to smaller wave numbers. In this case, the acetone vibration is located at 1690 cm⁻¹ and thus 25 cm⁻¹ lower than for uncoordinated acetone (see ESI Fig. S10^†).In the last step, the incorporated Cu²⁺ ions will be used for the detection of H₂S. With this approach it is possible to transfer the properties of the molecular complexes¹¹ into a solid state material, as we have already shown with a calixarene-based MOF for highly selective NO₂ detection.²⁶ It is generally assumed that the implicit chemical reaction is the formation of CuS.¹⁵ Upon this reaction, a fast and impressive colour change occurs from green to black which can be simply observed with the naked eye. Taking the diffraction patterns into account, it is noticeable that the above-mentioned shift of the 200-reflection is reversed upon H₂S exposure, indicating a change in the coordination of the copper ions (see Fig. 1c and ESI Fig. S4^†). After the exposure to H₂S, the BET area of all samples is drastically reduced (see ESI Fig. S14 and Table S7^†) which can be explained by pore blocking effects due to CuS formation.The formation of CuS can additionally be verified with Raman spectroscopy. Here, a weak CuS band can be found at 471 cm⁻¹ (see ESI Fig. S11^†). Again, this is an indication for the formation of CuS located inside the pore channels or on the surface of the MOFs as pore blocker. This is also an explanation for the decrease of the BET surfaces from the physisorption measurements. After the MOF has been exposed to H₂S, the acetone vibration disappears completely from the IR spectrum. This observation supports the thesis that the coordination of the copper ions at the azo groups and thus the Lewis acidic effect is no longer present after this step.Additionally, the experimental residue of the MOF is similar to the Cu²⁺ incorporated sample (see ESI Fig. S21 and Table S10^†) and is composed of ZrO₂ and CuO (see ESI Fig. S8^†). Moreover, the EDX measurement show a sulphur content in this sample which is comparable to the amount of copper and obviously CuS is formed (see ESI Fig. S20 and Table S9^†).The chemical reaction of the sensor response is the formation of CuS and the associated colour change from green to black. For the application as H₂S sensor material, the spectroscopic characteristics were determined. As already can be seen in the photographs in Fig. 1, the colouration becomes more pronounced with increasing amount of provided linker during the SALE and thus also of the amount of incorporated Cu²⁺. This observation is supported by the UV/Vis measurements. Here, the absorption also intensifies with increasing amounts of H₂abdc after the SALE in the range between 430 and 500 nm. The pure MIL-140D-sdc shows no absorption in this region at all (see ESI Fig. S22a^†). The integration of azo groups is essential for the incorporation of copper ions into the MOF and thus for the detection of H₂S. When a pure MIL-140D-sdc is immersed in a copper chloride solution it can be shown that no copper is coordinated by the MOFs by comparison of the UV/Vis spectra. The absorption does not change because no copper ions can be complexed by the sdc²⁻ linker of pure MIL-140D-sdc. When the copper treated MIL-140D-sdc was exposed for 30 minutes to 100 ppm H₂S no measurable difference in the spectra occurs (see Fig. S24^†). As a result, it can be concluded that no copper ions were deposited in the framework at all.After the incorporation of copper ions in the MIL-140D-sdc/abdc, a second absorption maximum at 730 nm is visible (see ESI Fig. S22b^†). As before, the maximum absorption increases with the amount of copper salt used. After exposure to H₂S, all samples immediately change their colour, whereby the highest absorption can be observed in the sample with the highest copper and abdc²⁻ content. At this point, the entire absorption in the visible range of the light spectrum increases (see ESI Fig. S22c and S23^†).During a 30 minute exposure to 100 ppm H₂S a cycled UV/Vis measurement was conducted to observe directly the change in the absorbance. Within less than 1 minute, an increase of the absorption between 550 and 600 nm is visible. After 30 minutes the saturation is reached and absorbance is approximately 450 percent higher compared to the starting material after the Cu²⁺ incorporation (see Fig. 2). For a more precise analysis, the sample was exposed to 100 ppm H₂S for 30 minutes and the absorbance at 580 nm was recorded every five seconds. Here the MOF exhibits almost no absorption after the incorporation of Cu²⁺. After the exposure to H₂S, the absorbance increases immediately and is again reaching a saturation point with an absorbance twice as high (see Fig. 3).Open in a separate windowFig. 2UV/Vis spectra of the MIL-140D-sdc/abdc after the SALE with H₂abdc (red), after the incorporation of Cu²⁺ (green) and after the exposure to 100 ppm H₂S with different time steps ranging from 1 to 30 minutes.Open in a separate windowFig. 3UV/Vis measurement of the Cu²⁺ incorporated sample (1 eq.) at 580 nm. Before the gas exposure (100 ppm H₂S) a baseline was measured under room conditions.The next step was to investigate the selectivity. For this purpose, the MOF was exposed to various gases such as CO₂ and CO (100 ppm), NO₂ (10 ppm) or stored in an NH₃ and diethyl ether (DEE) atmosphere for 30 minutes. In terms of stability, a partly decomposition occurs only in presence of CO due to its interaction with the azo group (see ESI Fig. S9^†).²⁷ Furthermore, the exposure to these gases results in a colour change for each sample, which can be explained by a ligand exchange at the coordinated copper ions (ESI Fig. S25^†).²⁸ Each sample was again investigated with UV/Vis spectroscopy and the main differences in the spectra are in the range of 400 to 550 and 650 to 800 nm (see ESI Fig. S26^†).The other examined gases cause only minor changes in the range of 580 nm. Only in the case of H₂S a significant change in the spectrum at this wavelength was observed, which should enable quantitative detection of this gas. The absorbances of the different samples at 580 nm are compared and set in relation to the original absorbance of the copper stored sample. The result is shown in Fig. 4, which demonstrates the high selectivity of this material for H₂S measured under these conditions.Open in a separate windowFig. 4Comparison of the differences in the absorbance of the sensor material in the presence of different gases (exposure time: 30 minutes). The measured values are all given in relation to the starting material whose absorbance was defined as 100%.In summary, it was demonstrated that through the post-synthetic step of the SALE a mixed-linker MOF has been obtained, the composition of which can be controlled by the amount of H₂abdc used in the SALE process. Furthermore, the new MIL-140D-sdc/abdc combines the stability of the MIL-140D-sdc framework and the functionality of the introduced azo groups. This again emphasizes the unique nature of the SALE for the production of differently functionalized frameworks and increases the tunability of manufactured materials. For the first time it was possible to use these linkers in a porous solid as coordination sites for copper ions. The porosity of the MOF is barely affected, making the coordinated metal ions accessible to guests. The guests can be different gases that coordinate under a ligand exchange with the copper ions. Nevertheless, this material has a high selectivity towards H₂S, which is expressed by the colour change from green to black, most likely due to the formation of CuS.The MIL-140D-sdc/abdc seems to be an interesting starting material for the coordination of various metals, due to the close arrangement of the linkers. Further, more elaborated, functional groups could help to optimize the sensing process or enhance the reversibility of the sensing reaction. This property can be used for further post-synthetic modifications of the linker and might also result in other attractive sensor materials.     

Total shoulder arthroplasty versus hemiarthroplasty for glenohumeral arthritis: A systematic review of the literature at long-term follow-up

Introduction:

The optimal surgical treatment of end-stage primary glenohumeral osteoarthritis remains controversial. The objective of this article is to systematically review the current available literature to formulate evidence-based guidelines for treatment of this pathology with an arthroplasty.

Materials and Methods:

A systematic literature search was performed to identify all articles from 1990 onward that presented data concerning treatment of glenohumeral arthritis with total shoulder arthroplasty (TSA) or head arthroplasty (HA) with a minimal follow-up of 7 years. The most relevant electronic databases were searched.

Results:

After applying the inclusion and exclusion criteria, we identified 18 studies (of the initial 832 hits). The search included a total of 1,958 patients (HA: 316 and TSA: 1,642) with 2,111 shoulders (HA: 328 + TSA: 1,783). The revision rate for any reason in the HA group (13%) was higher than in the TSA group (7%) (P < 0.001). There was a trend of a higher complication rate (of any kind) in the TSA group (12%) when compared with the HA group (8%) (P = 0.065). The weighted mean improvement in anteflexion, exorotation and abduction were respectively 33°, 15° and 31° in the HA group and were respectively 56°, 21° and 48° in the TSA group. Mean decrease in pain scores was 4.2 in the HA and 5.5 in the TSA group.

Conclusion:

Finally, we conclude that TSA results in less need for revision surgery, but has a trend to result in more complications. The conclusions of this review should be interpreted with caution as only Level IV studies could be included.

Level of Evidence:

IV.     

Influence of Preoperative and Postoperative Pelvic Floor Muscle Training (PFMT) Compared with Postoperative PFMT on Urinary Incontinence After Radical Prostatectomy: A Randomized Controlled Trial

Background

The efficacy of preoperative pelvic floor muscle training (PFMT) for urinary incontinence (UI) after open radical prostatectomy (ORP) and robot-assisted laparoscopic radical prostatectomy (RARP) is still unclear.

Objective

To determine whether patients with additional preoperative PFMT regain urinary continence earlier than patients with only postoperative PFMT after ORP and RARP.

Design, setting, and participants

A randomized controlled trial enrolled 180 men who planned to undergo ORP/RARP.

Intervention

The experimental group (E, n = 91) started PFMT 3 wk before surgery and continued after surgery. The control group (C, n = 89) started PFMT after catheter removal.

Outcome measurements and statistical analysis

The primary end point was time to continence. Patients measured urine loss daily (24-h pad test) until total continence (three consecutive days of 0 g of urine loss) was achieved. Secondary end points were 1-h pad test, visual analog scale (VAS), International Prostate Symptom Score (IPSS), and quality of life (King's Health Questionnaire [KHQ]). Kaplan-Meier analysis and Cox regression with correction for two strata (age and type of surgery) compared time and continence. The Fisher exact test was applied for the 1-h pad test and VAS; the Mann-Whitney U test was applied for IPSS and KHQ.

Results and limitations

Patients with additional preoperative PFMT had no shorter duration of postoperative UI compared with patients with only postoperative PFMT (p = 0.878). Median time to continence was 30 and 31 d, and median amount of first-day incontinence was 108 g and 124 g for groups E and C, respectively. Cox regression did not indicate a significant difference between groups E and C (p = 0.773; hazard ratio: 1.047 [0.768–1.425]). The 1-h pad test, VAS, and IPSS were comparable between both groups. However, “incontinence impact” (KHQ) was in favor of group E at 3 mo and 6 mo after surgery.

Conclusions

Three preoperative sessions of PFMT did not improve postoperative duration of incontinence.

Trial registration

Netherlands Trial Register No. NTR 1953.