A three-dimensional mathematical model of the thoracolumbar fascia and an estimate of its biomechanical effect.

The thoracolumbar fascia (TLF) provides a means of attachment to the lumbar spine for several muscles including the transverse abdominis, and parts of the latissimus dorsi and internal oblique muscles. Previous biomechanical models of the lumbar spine either tend to omit the TLF on the assumption that its contribution would be negligible or incorporate only part of the TLF. Here, a three-dimensional model of the posterior and middle layers of the TLF is presented to enable its action to be included in future three-dimensional models of the spine. It is used illustratively to estimate the biomechanical influence of this structure on the lumbar spine. The formulation of the model allows the lines of action of the fibres comprising the fascia to be calculated for any posture whilst ensuring that anatomical constraints are satisfied. Application of the model suggests that the TLF produces moments primarily in flexion and extension. The simulated results demonstrate that the abdominal muscles, acting via the TLF, are capable of contributing extension moments comparable to those produced by other smaller muscles associated with the lumbar spine.

The mechanical response of the ovine lumbar anulus fibrosus to uniaxial, biaxial and shear loads.

Analytical and computational models of the intervertebral disc (IVD) are commonly employed to enhance understanding of the biomechanics of the human spine and spinal motion segments. The accuracy of these models in predicting physiological behaviour of the spine is intrinsically reliant on the accuracy of the material constitutive representations employed to represent the spinal tissues. There is a paucity of detailed mechanical data describing the material response of the reinforced-ground matrix in the anulus fibrosus of the IVD. In the present study, the 'reinforced-ground matrix' was defined as the matrix with the collagen fibres embedded but not actively bearing axial load, thus incorporating the contribution of the fibre-fibre and fibre-matrix interactions. To determine mechanical parameters for the anulus ground matrix, mechanical tests were carried out on specimens of ovine anulus, under unconfined uniaxial compression, simple shear and biaxial compression. Test specimens of ovine anulus fibrosus were obtained with an adjacent layer of vertebral bone/cartilage on the superior and inferior specimen surface. Specimen geometry was such that there were no continuous collagen fibres coupling the two endplates. Samples were subdivided according to disc region - anterior, lateral and posterior - to determine the regional inhomogeneity in the anulus mechanical response. Specimens were loaded at a strain rate sufficient to avoid fluid outflow from the tissue and typical stress-strain responses under the initial load application and under repeated loading were determined for each of the three loading types. The response of the anulus tissue to the initial and repeated load cycles was significantly different for all load types, except biaxial compression in the anterior anulus. Since the maximum applied strain exceeded the damage strain for the tissue, experimental results for repeated loading reflected the mechanical ability of the tissue to carry load, subsequent to the initiation of damage. To our knowledge, this is the first study to provide experimental data describing the response of the 'reinforced-ground matrix' to biaxial compression. Additionally, it is novel in defining a study objective to determine the regionally inhomogeneous response of the 'reinforced-ground matrix' under an extensive range of loading conditions suitable for mechanical characterisation of the tissue. The results presented facilitate the development of more detailed and comprehensive constitutive descriptions for the large strain nonlinear elastic or hyperelastic response of the anulus ground matrix.

Development of a biaxial compression device for biological samples: preliminary experimental results for a closed cell foam.

Biological tissues are subjected to complex loading states in vivo and in order to define constitutive equations that effectively simulate their mechanical behaviour under these loads, it is necessary to obtain data on the tissue's response to multiaxial loading. Single axis and shear testing of biological tissues is often carried out, but biaxial testing is less common. We sought to design and commission a biaxial compression testing device, capable of obtaining repeatable data for biological samples. The apparatus comprised a sealed stainless steel pressure vessel specifically designed such that a state of hydrostatic compression could be created on the test specimen while simultaneously unloading the sample along one axis with an equilibrating tensile pressure. Thus a state of equibiaxial compression was created perpendicular to the long axis of a rectangular sample. For the purpose of calibration and commissioning of the vessel, rectangular samples of closed cell ethylene vinyl acetate (EVA) foam were tested. Each sample was subjected to repeated loading, and nine separate biaxial experiments were carried out to a maximum pressure of 204 kPa (30 psi), with a relaxation time of two hours between them. Calibration testing demonstrated the force applied to the samples had a maximum error of 0.026 N (0.423% of maximum applied force). Under repeated loading, the foam sample demonstrated lower stiffness during the first load cycle. Following this cycle, an increased stiffness, repeatable response was observed with successive loading. While the experimental protocol was developed for EVA foam, preliminary results on this material suggest that this device may be capable of providing test data for biological tissue samples. The load response of the foam was characteristic of closed cell foams, with consolidation during the early loading cycles, then a repeatable load-displacement response upon repeated loading. The repeatability of the test results demonstrated the ability of the test device to provide reproducible test data and the low experimental error in the force demonstrated the reliability of the test data.

Nonlinear finite element analysis of anular lesions in the L4/5 intervertebral disc.

Degenerate intervertebral discs exhibit both material and structural changes. Structural defects (lesions) develop in the anulus fibrosus with age. While degeneration has been simulated in numerous previous studies, the effects of structural lesions on disc mechanics are not well known. In this study, a finite element model (FEM) of the L4/5 intervertebral disc was developed in order to study the effects of anular lesions and loss of hydrostatic pressure in the nucleus pulposus on the disc mechanics. Models were developed to simulate both healthy and degenerate discs. Degeneration was simulated with either rim, radial or circumferential anular lesions and by equating nucleus pressure to zero. The anulus fibrosus ground substance was represented as a nonlinear incompressible material using a second-order polynomial, hyperelastic strain energy equation. Hyperelastic material parameters were derived from experimentation on sheep discs. Endplates were assumed to be rigid, and annulus lamellae were assumed to be vertical in the unloaded state. Loading conditions corresponding to physiological ranges of rotational motion were applied to the models and peak rotation moments compared between models. Loss of nucleus pulposus pressure had a much greater effect on the disc mechanics than the presence of anular lesions. This indicated that the development of anular lesions alone (prior to degeneration of the nucleus) has minimal effect on disc mechanics, but that disc stiffness is significantly reduced by the loss of hydrostatic pressure in the nucleus. With the degeneration of the nucleus, the outer innervated anulus or surrounding osteo-ligamentous anatomy may therefore experience increased strains.

Biomechanical concepts and effects.

Superficial tissue ulceration can be caused by the effect of mechanical loads acting on localised areas of skin and subcutaneous tissues. Be they low sustained loads applied for long periods or higher loads intermittently applied, the importance of the time factor has been recognised clinically by doctors and nurses. The significance of the type of loading and its magnitude in the damage of tissue is, however, not well agreed. This is in part due to the fact that knowledge of the mechanical and physiological responses of tissues is limited and in part to an inability to measure the forces applied to the tissues. This presentation outlines current understanding of the mechanics of tissue response.

Complementary and miscellaneous interventions for nocturnal enuresis in children.

BACKGROUND: Nocturnal enuresis (bedwetting) is a socially disruptive and stressful condition which affects around 15 to 20% of five year olds, and up to 2% of young adults. OBJECTIVES: To assess the effects of complementary interventions and others such as surgery or diet on nocturnal enuresis in children, and to compare them with other interventions. SEARCH STRATEGY: We searched the Cochrane Incontinence Group Specialised Register (searched 22 November 2004), the Traditional Chinese Medical Literature Analysis and Retrieval System (TCMLARS) (January 1984 to June 2004) and the reference lists of relevant articles. SELECTION CRITERIA: All randomised or quasi-randomised trials of complementary and other miscellaneous interventions for nocturnal enuresis in children were included except those focused solely on daytime wetting. Comparison interventions could include no treatment, placebo or sham treatment, alarms, simple behavioural treatment, desmopressin, imipramine and miscellaneous other drugs and interventions. DATA COLLECTION AND ANALYSIS: Two reviewers independently assessed the quality of the eligible trials, and extracted data. MAIN RESULTS: In 15 randomised controlled trials, 1389 children were studied, of whom 703 received a complementary intervention. The quality of the trials was poor: four trials were quasi-randomised, five showed differences at baseline and ten lacked follow up data. The outcome was better after hypnosis than imipramine in one trial (relative risk (RR) for failure or relapse after stopping treatment 0.42, 95% confidence interval (CI) 0.23 to 0.78). Psychotherapy appeared to be better in terms of fewer children failing or relapsing than both alarm (RR 0.28, 95% CI 0.09 to 0.85) and rewards (0.29, 95% 0.09 to 0.90) but this depended on data from only one trial. Acupuncture had better results than sham control acupuncture (RR for failure or relapse after stopping treatment 0.67, 95% CI 0.48 to 0.94) in a further trial. Active chiropractic adjustment had better results than sham adjustment (RR for failure or relapse after stopping treatment 0.74, 95% CI 0.60 to 0.91). However, each of these findings came from small single trials, and need to be verified in further trials. The findings for diet and faradization were unreliable, and there were no trials including homeopathy or surgery. AUTHORS' CONCLUSIONS: There was weak evidence to support the use of hypnosis, psychotherapy, acupuncture and chiropractic but it was provided in each case by single small trials, some of dubious methodological rigour. Robust randomised trials are required with efficacy, cost-effectiveness and adverse effects carefully monitored.

Alarm interventions for nocturnal enuresis in children.

BACKGROUND: Enuresis (bedwetting) is a socially disruptive and stressful condition which affects around 15 to 20% of five year olds, and up to 2% of young adults. OBJECTIVES: To assess the effects of alarm interventions on nocturnal enuresis in children, and to compare alarms with other interventions. SEARCH STRATEGY: We searched the Cochrane Incontinence Group specialised trials register (searched 22 November 2004) and the reference lists of relevant articles. SELECTION CRITERIA: All randomised or quasi-randomised trials of alarm interventions for nocturnal enuresis in children were included, except those focused solely on daytime wetting. Comparison interventions included no treatment, simple and complex behavioural methods, desmopressin, tricyclics, and miscellaneous other methods. DATA COLLECTION AND ANALYSIS: Two reviewers independently assessed the quality of the eligible trials, and extracted data. MAIN RESULTS: Fifty five trials met the inclusion criteria, involving 3152 children of whom 2345 used an alarm. The quality of many trials was poor, and evidence for many comparisons was inadequate. Most alarms used audio methods. Compared to no treatment, about two thirds of children became dry during alarm use (RR for failure 0.38, 95% CI 0.33 to 0.45). Nearly half who persisted with alarm use remained dry after treatment finished, compared to almost none after no treatment (RR of failure or relapse 45/81 (55%) vs 80/81 (99%), RR 0.56, 95% CI 0.46 to 0.68). There was insufficient evidence to draw conclusions about different types of alarm, or about how alarms compare to other behavioural interventions. Relapse rates were lower when overlearning was added to alarm treatment (RR 1.92, 95% CI 1.27 to 2.92) or if dry bed training was used as well (RR 2.0, 95% CI 1.25 to 3.20). Penalties for wet beds appeared to be counter-productive. Alarms using electric shocks were unacceptable to children or their parents. Although desmopressin may have a more immediate effect, alarms appear more effective by the end of a course of treatment (RR 0.71, 95% CI 0.50 to 0.99) and there was limited evidence of greater long-term success (4/22 (18%) vs 16/24 (67%), RR 0.27, 95% CI 0.11 to 0.69). Evidence about the benefit of supplementing alarm treatment with desmopressin was conflicting. Alarms were better than tricyclics during treatment (RR 0.73, 95% CI 0.61 to 0.88) and afterwards (7/12 (58%) vs 12/12 (100%), RR 0.58, 95% CI 0.36 to 0.94). AUTHORS' CONCLUSIONS: Alarm interventions are an effective treatment for nocturnal bedwetting in children. Alarms appear more effective than desmopressin or tricyclics by the end of treatment, and subsequently. Overlearning (giving extra fluids at bedtime after successfully becoming dry using an alarm), dry bed training and avoiding penalties may further reduce the relapse rate. Better quality research comparing alarms with other treatments is needed, including follow-up to determine relapse rates.

Simple behavioural and physical interventions for nocturnal enuresis in children.

BACKGROUND: Nocturnal enuresis (bedwetting) is a socially disruptive and stressful condition which affects around 15-20% of five year olds, and up to 2% of young adults. Although there is a high rate of spontaneous remission, the social, emotional and psychological costs can be great. Simple behavioural methods of treating bedwetting include reward systems such as star charts given for dry nights, lifting or waking the children at night to urinate, retention control training to enlarge bladder capacity (bladder training) and fluid restriction. OBJECTIVES: To assess the effects of simple behavioural interventions on nocturnal enuresis in children, and to compare these with other interventions. SEARCH STRATEGY: We searched the Cochrane Incontinence Group trials register (searched 18 September 2003). The reference list of a previous version of this review was also searched. SELECTION CRITERIA: All randomised or quasi-randomised trials of simple behavioural interventions for nocturnal enuresis in children up to the age of 16. Trials focused solely on daytime wetting were excluded. DATA COLLECTION AND ANALYSIS: Two reviewers independently assessed the quality of the eligible trials and extracted data. MAIN RESULTS: Thirteen trials met the inclusion criteria, involving 702 children of whom 387 received a simple behavioural intervention. However, within each comparison each outcome was addressed by single trials only, precluding meta-analysis. In single small trials, reward systems (e.g. star charts), lifting and waking were each associated with significantly fewer wet nights, higher cure rates and lower relapse rates compared to controls. There was not enough evidence to evaluate retention control training (bladder training), whether compared with controls or dry bed training, or used as a supplement to alarms, or versus desmopressin. Cognitive therapy may have lower failure and relapse rates than star charts, but this finding was based on one small trial only. One small trial of poor quality suggested that star charts were initially less successful than amitriptyline but this difference did not persist after the treatments stopped. Another suggested that imipramine was better than fluid deprivation and avoidance of punishment. REVIEWERS' CONCLUSIONS: Simple behavioural methods may be effective for some children, but further trials are needed, in particular in comparison with treatments known to be effective, such as desmopressin, tricyclic drugs and alarms. However, simple methods could be tried as first line therapy before considering alarms or drugs, because these alternative treatments may be more demanding and may have adverse effects.

Complex behavioural and educational interventions for nocturnal enuresis in children.

BACKGROUND: Nocturnal enuresis (bedwetting) is a socially disruptive and stressful condition which affects around 15-20% of five year olds, and up to 2% of young adults. OBJECTIVES: To assess the effects of complex behavioural and educational interventions on nocturnal enuresis in children, and to compare them with other interventions. SEARCH STRATEGY: We searched the Cochrane Incontinence Group trials register (December 2002) and the reference lists of relevant articles. Date of the most recent searches: December 2002. SELECTION CRITERIA: All randomised or quasi-randomised trials of complex behavioural or educational interventions for nocturnal enuresis in children were included, except those focused solely on daytime wetting. Comparison interventions included no treatment, simple and physical behavioural methods, alarms, desmopressin, tricyclics, and miscellaneous other interventions. DATA COLLECTION AND ANALYSIS: Two reviewers independently assessed the quality of the eligible trials, and extracted data. MAIN RESULTS: Sixteen trials involving 1081 children were identified which included a complex or educational intervention for nocturnal enuresis. The trials were mostly small and some had methodological problems including the use of a quasi-randomised method of concealment of allocation in three trials and baseline differences between the groups in another three.A complex intervention (such as dry bed training (DBT) or full spectrum home training (FSHT)) including an alarm was better than no-treatment control groups (eg RR for failure or relapse after stopping DBT 0.25; 95% CI 0.16 to 0.39) but there was not enough evidence about the effects of complex interventions alone if an alarm was not used. A complex intervention on its own was not as good as an alarm on its own or the intervention supplemented by an alarm (eg RR for failure or relapse after DBT alone versus DBT plus alarm 2.81; 95% CI 1.80 to 4.38). On the other hand, a complex intervention supplemented by a bed alarm might reduce the relapse rate compared with the alarm on its own (eg RR for failure or relapse after DBT plus alarm versus alarm alone 0.5; 95% CI 0.31 to 0.80).There was not enough evidence to judge whether providing educational information about enuresis was effective, irrespective of method of delivery. There was some evidence that direct contact between families and therapists enhanced the effect of a complex intervention, and that increased contact and support enhanced a package of simple behavioural interventions, but these were addressed only in single trials and the results would need to be confirmed by further randomised controlled trials, in particular the effect on use of resources. REVIEWER'S CONCLUSIONS: Although DBT and FSHT were better than no treatment when used in combination with an alarm, there was insufficient evidence to support their use without an alarm. An alarm on its own was also better than DBT on its own, but there was some evidence that combining an alarm with DBT was better than an alarm on its own, suggesting that DBT may augment the effect of an alarm. There was also some evidence that direct contact with a therapist might enhance the effects of an intervention.

Effects of interventions for the treatment of nocturnal enuresis in children.

The effectiveness of interventions for the treatment of nocturnal enuresis in children published in a recent issue of Effective Health Care is reviewed.

Drugs for nocturnal enuresis in children (other than desmopressin and tricyclics).

BACKGROUND: Enuresis (bedwetting) is a socially stigmatising and stressful condition which affects around 15-20% of five year olds, and up to 2% of young adults. Although there is a high rate of spontaneous remission, the social, emotional and psychological costs to the children can be great. OBJECTIVES: To assess the effects of drugs other than desmopressin and tricyclics on nocturnal enuresis in children, and to compare them with other interventions. SEARCH STRATEGY: We searched the Cochrane Incontinence Group trials register. Date of the most recent search: December 2002. The reference list of a previous version of this review was also searched. SELECTION CRITERIA: All randomised trials of drugs (excluding desmopressin or tricyclics) for nocturnal enuresis in children were included in the review. Trials were eligible for inclusion if children were randomised to receive drugs compared with placebo, other drugs or other conservative interventions for nocturnal bedwetting. Trials focused solely on daytime wetting were excluded. DATA COLLECTION AND ANALYSIS: Two reviewers independently assessed the quality of the eligible trials and extracted data. MAIN RESULTS: In 32 randomised controlled trials (25 new in this update), a total of 1225 out of 1613 children received an active drug other than desmopressin or a tricyclic. In all, 28 different drugs or classes of drugs were tested, but the trials were generally small or of poor methodological quality (five were quasi-randomised and the remainder failed to give adequate details about the randomisation process). Although indomethacin and diclofenac were better than placebo during treatment, desmopressin was better than both of them, with less chance of adverse effects. There were no data regarding what happened after treatment stopped. Limited data suggested that an alarm was better than drugs during treatment. REVIEWER'S CONCLUSIONS: There was not enough evidence to judge whether the included drugs reduced bedwetting. There was limited evidence to suggest that desmopressin, imipramine and alarms were better than the drugs to which they were compared. In other reviews, desmopressin, tricyclics and alarm interventions have been shown to be effective.

Tricyclic and related drugs for nocturnal enuresis in children.

BACKGROUND: Enuresis (bedwetting) is a socially disruptive and stressful condition which affects around 15-20% of five year olds, and up to 2% of young adults. OBJECTIVES: To assess the effects of tricyclic and related drugs on nocturnal enuresis in children, and to compare them with other interventions. SEARCH STRATEGY: We searched the Cochrane Incontinence Group trials register (December 2002) and the reference lists of relevant articles including two previously published versions of this review. Date of the most recent searches: December 2002. SELECTION CRITERIA: All randomised and quasi-randomised trials of tricyclics or related drugs for nocturnal enuresis in children were included in the review. Comparison interventions included placebo, other drugs, alarms, behavioural methods or complementary/miscellaneous interventions. Trials focused solely on daytime wetting were excluded. DATA COLLECTION AND ANALYSIS: Two reviewers independently assessed the quality of the eligible trials, and extracted data. MAIN RESULTS: Fifty four randomised trials met the inclusion criteria, involving 3379 children. The quality of many of the trials was poor. Most comparisons or outcomes were addressed only by single trials. Treatment with most tricyclic drugs (such as imipramine, amitriptyline, viloxazine, nortriptyline, clomipramine and desipramine) was associated with a reduction of about one wet night per week while on treatment (eg imipramine compared with placebo, weighted mean difference (WMD) -1.19, 95% CI -1.56 to -0.82). The exception was mianserin, where results from one small trial did not reach statistical significance. About a fifth of the children became dry while on treatment (relative risk for failure (RR) 0.77, 95% CI 0.72 to 0.83), but this effect was not sustained after treatment stopped (eg imipramine versus placebo, RR 0.98, 95% CI 0.95 to 1.03). There was not enough information to assess the relative performance of one tricyclic against another, except that imipramine was better than mianserin. The evidence comparing desmopressin with tricyclics was unreliable or conflicting, but in one small trial all the children failed or relapsed after stopping active treatment with either drug.The evidence comparing tricyclics with alarms was also unreliable or conflicting during treatment. In one small trial all the children failed or relapsed after tricyclics stopped, compared with about half after alarms. This result was compatible with the results in the Cochrane review of alarm treatment, which found that about half the children remained dry after alarm treatment was finished. There was a little evidence from single trials to suggest that imipramine might be better than a simple reward system with star charts during treatment; worse than a complex intervention involving education, counseling, waking and retention control training; better than a restricted diet; and worse than hypnosis. However, these results need to be confirmed by further research. REVIEWER'S CONCLUSIONS: Although tricyclics and desmopressin are effective in reducing the number of wet nights while taking the drugs, most children relapse after stopping active treatment. In contrast, only half the children relapse after alarm treatment. Parents should be warned of the potentially serious adverse effects of tricyclic overdose when choosing treatment. Further research is needed into comparisons between drug and behavioural or complementary treatments, and should include relapse rates after treatment is finished.

Alarm interventions for nocturnal enuresis in children.

BACKGROUND: Enuresis (bedwetting) is a socially disruptive and stressful condition which affects around 15-20% of five year olds, and up to 2% of young adults. OBJECTIVES: To assess the effects of alarm interventions on nocturnal enuresis in children, and to compare alarms with other interventions. SEARCH STRATEGY: We searched the Cochrane Incontinence Group trials register (December 2002) and the reference lists of relevant articles. Date of the most recent searches: December 2002. SELECTION CRITERIA: All randomised or quasi-randomised trials of alarm interventions for nocturnal enuresis in children were included, except those focused solely on daytime wetting. Comparison interventions included no treatment, simple and complex behavioural methods, desmopressin, tricyclics, and miscellaneous other methods. DATA COLLECTION AND ANALYSIS: Two reviewers independently assessed the quality of the eligible trials, and extracted data. MAIN RESULTS: Fifty three trials met the inclusion criteria, involving 2862 children. The quality of many trials was poor, and evidence for many comparisons was inadequate. Most alarms used audio methods. Compared to no treatment, about two thirds of children became dry during alarm use (RR for failure 0.36, 95% CI 0.31 to 0.43). Nearly half who persisted with alarm use remained dry after treatment finished, compared to almost none after no treatment (RR of failure or relapse 45/81 (55%) vs 80/81 (99%), RR 0.56, 95% CI 0.46 to 0.68). There was insufficient evidence to draw conclusions about different types of alarm, or about how alarms compare to other behavioural interventions. Relapse rates were lower when overlearning was added to alarm treatment (RR 1.92, 95% CI 1.27 to 2.92). Penalties for wet beds appeared to be counter-productive. Alarms using electric shocks were unacceptable to children or their parents. Although desmopressin may have a more immediate effect, alarms appear more effective by the end of a course of treatment (RR 0.71, 95% CI 0.50 to 0.99) and there was limited evidence of greater long-term success (RR 4/22 (18%) vs 16/24 (67%),RR 0.27, 95% CI 0.11 to 0.69). Alarms were better than tricyclics during treatment (RR 0.73, 95% CI 0.61 to 0.88) and afterwards (7/12 (58%) vs 12/12 (100%), RR 0.58, 95% CI 0.36 to 0.94). REVIEWER'S CONCLUSIONS: Alarm interventions are an effective treatment for nocturnal bedwetting in children. Alarms appear more effective than desmopressin or tricyclics by the end of treatment, and subsequently. Overlearning (giving extra fluids at bedtime after successfully becoming dry using an alarm) and avoiding penalties may further reduce the relapse rate. Better quality research comparing alarms with other treatments is needed, including follow-up to determine relapse rates.

Multimedia versus written information for nocturnal enuresis education: a cluster randomized controlled trial.

OBJECTIVE: This study evaluated the impact of child-focused information provision using a multimedia software package 'All About Nocturnal Enuresis' and written leaflets containing the same information for bedwetting children. DESIGN: A stratified cluster randomized controlled trial with data on 270 children collected longitudinally. SETTING: Fifteen school nurse-led community enuresis clinics in Leicestershire, UK. MAIN OUTCOME MEASURES: The outcome measures were becoming and remaining dry and time to dry, non-attendance and dropout rates. The psychological measures completed by children were the impact of bedwetting and Coopersmith self-esteem scales. Parents completed the maternal tolerance scale. RESULTS: No significant intervention effect was found for any of the outcome measures recorded during treatment, at discharge or six-months post discharge. CONCLUSIONS: Multimedia educational programs and written leaflets are widely used to enable children to learn more about their health-related conditions. However, our result suggests that multimedia is no more effective than traditional materials at effecting health-related behavioural change.

Synthesis and characterization of hydroxyapatite, fluoride-substituted hydroxyapatite and fluorapatite.

Powders of hydroxyapatite (HA), partially fluoride-substituted hydroxyapatite (fHA), and fluorapatite (FA) were synthesized in house using optimum methods to achieve relatively pure powders. These powders were assessed by the commonly used bulk techniques of X-ray diffraction (XRD), Fourier transform infra-red (FTIR) and FT-Raman spectroscopies, inductively coupled plasma atomic emission spectroscopy (ICP-AES), and F-selective electrode. In addition, the current study has employed transmission electron microscopy (TEM), involving morphological observation, electron diffraction and energy-dispersive X-ray spectrometry (EDX), as an effective analytical technique to evaluate the powders at a microscopic level. The HA and fHA particles were elongated platelets about 20 x 60 nm in size, while FA particles were over twice this size. Calcination of the HA and fHA powders at 1000 degrees C for 1 h resulted in increased grain size and crystallinity. The calcined fHA material appeared to possess a crystal structure intermediate between HA and FA, as evidenced by the (3 0 0) peak shift in XRD, as well as by the position of the hydroxyl bands in the FTIR spectra. This result was consistent with electron diffraction of individual particles. Small levels of impurities in some of the powders were identified by EDX and electron diffraction, and the carbonate content was detected by FTIR. The use of TEM in conjunction with the bulk techniques has allowed a more thorough assessment of the apatites, and has enabled the constituents in these closely related apatite powders to be identified.

Effect of using prismatic eye lenses on the posture of patients with adolescent idiopathic scoliosis measured by 3-d motion analysis.

This is a preliminary investigation to detect the body sway and postural changes of patients with AIS under different spatial images. Two pairs of low-power prismatic eye lenses (Fresnel prisms) with 5 dioptre and 10 dioptre were used. In the experiment, the apices of the prisms were orientated randomly at every 22.5 degrees from 0 degrees to 360 degrees to test changes. Four patients with mean age of 11 and Cobb's angle of 30 degrees were recruited and the results showed that the low-power prisms at specific orientations (157.5 degrees and 180 degrees) could cause positive postural changes (2.1 degrees-2.7 degrees reduction of angle of trunk mis-alignment) measured by 3-D motion analysis. This might be used for controlling their scoliotic curves by induced visual bio-feedback. Apart from this laboratory test, a longitudinal study is necessary to investigate the long-term effect of the prisms at different powers and orientations (under both static and dynamic situations) on the patient's posture, spinal muscular activities, vision, eye-hand coordination, psychological state and other daily activities before it becomes an alternative management of AIS.

An investigation of the impact of nocturnal enuresis on children's self-concept.

OBJECTIVE: This study sought to evaluate the relationship between the self-esteem and the self-image of children with nocturnal enuresis and to examine these in relation to various aspects of clinical and demographic variables. Previous studies investigating the self-esteem of bedwetting children have had mixed findings. Some studies report that children with nocturnal enuresis have a lower self-esteem than their non-bedwetting peers, but other studies report that children with nocturnal enuresis perceive themselves similarly to non-bedwetting children. However, what have not been studied to date are the self-perceptions of bedwetting children treated in community clinics. MATERIAL AND METHODS: A total of 114 bedwetting children treated in community clinics provided the sample. School nurses conducted a routine first-visit assessment, collected baseline demographic and social information and invited children to complete the Butler Self-Image Profile and the Coopersmith Self-Esteem Inventory. RESULTS: Age and extent of wetting were not significantly related to self-concept measures. Girls had significantly (p = 0.008) higher scores on positive self-image compared with boys. Children with secondary enuresis also scored higher on positive self-image compared with those with primary nocturnal enuresis (p = 0.02). The Butler self-image scores indicated a number of significant links between positive self-image and enuresis variables, whereas the Coopersmith self-esteem scores generally failed to distinguish between the enuresis variables and closely reflected those of the negative self-image scores. CONCLUSIONS: These findings suggest that amongst children with nocturnal enuresis, the most vulnerable in terms of self-image are male, those with primary enuresis and those with a greater number of wet nights a week.

Desmopressin for nocturnal enuresis in children.

BACKGROUND: Enuresis (bedwetting) is a socially disruptive and stressful condition which affects around 15-20% of five year olds, and up to 2% of young adults. OBJECTIVES: To assess the effects of desmopressin on nocturnal enuresis in children, and to compare desmopressin with other interventions. SEARCH STRATEGY: We searched the Cochrane Incontinence Group trials register. Date of the most recent search: March 2002. The reference list of a previous version of this review was also searched. SELECTION CRITERIA: All randomised trials of desmopressin for nocturnal enuresis in children were included in the review. Comparison interventions included placebo, other drugs, alarms or behavioural methods. Trials focused solely on daytime wetting were excluded. DATA COLLECTION AND ANALYSIS: Two reviewers independently assessed the quality of the eligible trials, and extracted data. MAIN RESULTS: Forty one randomised trials involving 2760 children (of whom 1813 received desmopressin) met the inclusion criteria. The quality of many of the trials was poor. Desmopressin was compared with another drug in four trials, and with alarms in seven. Desmopressin was effective in reducing bedwetting in a variety of doses and forms. Each dose of desmopressin reduced bedwetting by at least one night per week during treatment compared with placebo (e.g. 20 microg: 1.34 fewer wet nights per week, 95% CI 1.11 to 1.57). Children on desmopressin were more likely to become dry (e.g. RR for failure to achieve 14 dry nights with 20 mcg 0.84, 95% CI 0.79 to 0.91). However, there was no difference after treatment was finished. There was no clear dose-related effect of desmopressin, but the evidence was limited. Data which compared oral and nasal administration were too few to be conclusive. While desmopressin was better than diclofenac or indomethacin, and comparison with tricyclic drugs (amitriptyline and imipramine) suggested that they might be as effective as desmopressin, the data were inconclusive due to small numbers. There were more side effects with the tricyclics. In one small trial, desmopressin resulted in more wet nights than alarms towards the end of treatment (WMD 1.4, 95% CI: 0.14 to 2.66) and the chance of failure or relapse after alarms was less (RR 9.17, 95% CI 1.28 to 65.90). Although there were fewer wet nights during alarm treatment supplemented by desmopressin compared with alarms alone (WMD -1.35, 95% CI -2.32 to -0.38), the data are inconclusive about whether this is reflected in lower failure (RR 0.88, 95%CI 0.52 to 1.50) or subsequent relapse rates (RR 0.58, 95% CI 0.31 to 1.10). REVIEWER'S CONCLUSIONS: Desmopressin rapidly reduced the number of wet nights per week, but there was some evidence that this was not sustained after treatment stopped. Comparison with alternative treatments suggested that desmopressin and tricyclics had similar clinical effects, but that alarms may produce more sustained benefits. However, based on the available limited evidence, these conclusions can only be tentative. Children should be advised not to drink more than 240 ml (8 oz) fluid during desmopressin treatment in order to avoid the possible risk of water intoxication.