[Risk factors for low back pain among 1.389 pupils in the 8th and 9th grade. An epidemiologic study]. / Risikofaktorer for laendesmerter hos 1.389 skoleelever i 8.- og 9.-klasse. Et epidemiologisk studie.

INTRODUCTION: The aim of this study was to investigate the frequency and severity of low back pain (LBP) in 13-16-year-old pupils in relation to selected factors, such as anthropometry, physical activity, smoking, hypermobility, and tightness of hamstring muscles. METHODS: The study was designed as a cross-sectional questionnaire-based survey and all the pupils were examined by the school doctor for height, weight, mobility of joints, and general health status. RESULTS: The lifetime prevalence of non-specific LBP was 58.9% and the one-year prevalence was 50.8% with no differences between the sexes. Recurrent/continuous LBP in a moderate to severe degree was recorded in 19.4% of the school children (182 F, 88 M). This was positively correlated to a female gender, a BMI of more than 25 kg/square meter, competitive sports for boys, poor physical fitness, daily smoking, heavy jobs in leisure time, increased use of the health system, and reduced life quality. DISCUSSION: Stepwise logistic regression analysis indicates that a female gender, daily smoking, and heavy jobs are important associated factors for severe LBP in adolescents, with an observed probability of 46% if all factors are present. We do not know yet whether these factors have any causal importance for the development of severe LBP.

Combined cataract and glaucoma surgery.

The management of cataract in glaucoma patients has been continuously changing over the past decade. Extracapsular cataract extraction has been replaced by small-incision phacoemulsification with foldable lenses, and in glaucoma surgery, adjunctive antifibrotic therapy based on risk factors for failure has become standard. Furthermore, new techniques in filtering and nonfiltering surgery have been suggested. The techniques, however, change so fast that well-controlled studies with a follow-up of more than 12 months are increasingly seldom. The purpose of this paper is to review the current literature and to point out some new ideas for the future investigation.

Possible factors modifying the surgically induced astigmatism in cataract surgery.

PURPOSE: To investigate possible modifiers of the surgically induced astigmatism with special reference to age, gender, preoperative astigmatism, and the intraocular pressure. METHODS & PATIENTS: Data for one hundred and one cataract patients operated on with extracapsular cataract extraction and intraocular lens implantation were prospectively recorded and followed for six years. Different explanatory variables like age, gender, preoperative astigmatism and postoperative intraocular pressure (IOP) were considered. Astigmatic changes were calculated as Naeser's polar values. RESULTS: The surgically induced astigmatism was not significant at one year, but was significantly increased 3- and 6-years postoperatively. At the same time the keratometric axis made a shift toward against-the-rule astigmatism. The postoperative mean-IOP was lower at all controls. Multiple regression analysis showed that a large preoperative astigmatism, a low postoperative IOP, and high age resulted in more surgically induced astigmatism against-the-rule. CONCLUSION: The length and the architecture of the incision are known to have an influence on the surgically induced astigmatism in cataract surgery. In the present study we used a multiple regression analysis model to show a significant correlation between the surgically induced astigmatism and age, preoperative astigmatism, and postoperative IOP.

Risk factors for low back pain in a cohort of 1389 Danish school children: an epidemiologic study.

This study was designed as a cross-sectional questionnaire-based survey of low back pain (LBP) in 13- to 16-year-old Danish school children. The cohort consisted of 671 boys and 718 girls in eighth and ninth grade in 46 municipal schools in three counties of Sealand. All the pupils filled in a questionnaire with LBP as the main topic and were at the same time examined by the school doctors. The first part of the questionnaire contained questions about leisure time sports activity, TV watching, PC use, job in leisure time and smoking. The second part dealt with LBP in relation to frequency and severity, influence on daily living and use of the health system. The school doctor measured body height and weight, (BMI), degree of hypermobility and the tightness of the hamstring muscles. The results showed a cumulative life-time prevalence of LBP of 58.9%, a 1-year prevalence of 50.8% and an increase in LBP prevalence of 6.4% from 14 to 15 years of age, independent of gender. Fourteen percent (141 F, 54 M) fulfilled the criteria for general hypermobility and 12.2% (45 F, 124 M) had tightness of hamstring muscles of more than 40 degrees. Recurrent/continuous LBP in a moderate to severe degree was recorded in 19.4% of children (182 F, 88 M). This was positively correlated to female gender, BMI more than 25 kg/m(2), competitive sport for boys, poor physical fitness, daily smoking, heavy jobs in leisure time, increased use of the health system and reduced life quality. Stepwise logistic regression analysis indicates that female gender, daily smoking and heavy jobs are important associated factors for severe LBP in adolescents, with an observed probability of 46% if all factors are present. We don't know yet whether these factors are of any causal importance in the development of severe LBP.

Retinal detachment after cataract extraction in myopic eyes.

PURPOSE: To determine the incidence of retinal detachment (RD) after cataract extraction in people 40 years of age or older with axial myopia (i.e., axial length > or = 25.5 mm). SETTING: Fifteen Danish eye clinics. METHODS: Two hundred forty-five eyes had cataract extraction performed at 15 eye clinics; 237 eyes had extracapsular cataract extraction (ECCE) and 8 eyes, intracapsular cataract extraction (ICCE). Postoperative data were reported by the practicing ophthalmologists. Mean follow-up was 27 months (range 14 to 32 months). RESULTS: Five RDs occurred in the 245 eyes (2.0%). Excluding the ICCE cases and the two cases of combined cornea transplantation and ECCE, RD occurred in 4 of the 235 eyes that had ECCE (1.7%). The incidence after ECCE with posterior chamber lens implantation was 1.4%. Complete postoperative status was reported on 158 eyes. Forty-eight eyes (30.4%) had a neodymium:YAG capsulotomy and 3 (6.0%) developed an RD 1, 3.5, and 21 months after the capsulotomy. CONCLUSION: The RD incidence after ECCE with posterior chamber lens implantation was low but higher than that in unselected populations. The incidence increased after laser capsulotomy.

Antibiotics in irrigation solution for cataract surgery. A laboratory investigation of the pharmacological stability and bacteriological susceptibility.

PURPOSE: To evaluate the appropriateness of a prophylactic use of Gentamicin and Vancomycin in the irrigation solution for cataract surgery. METHODS: A laboratory study of the pharmacological stability and the bacteriological susceptibility of the two antibiotics and epinephrine in the irrigation solution. RESULTS: Gentamicin and Vancomycin are pharmacologically stable in concentrations above the MIC-values of most Gram positive and Gram negative bacteria without reaching toxic levels. CONCLUSION: Although it seems tempting to add Gentamicin and Vancomycin in irrigation solutions for cataract surgery, major objections to such a prophylactic use of antibiotics have been stated, specially focusing on the risk of emerging resistance to the antibiotics, and the financial implications.

A prospective study of combined phacoemulsification-trabeculectomy versus conventional phacoemulsification in cataract patients with coexisting open angle glaucoma.

This prospective study compares combined phacoemulsification and trabeculectomy (phaco-trab) to conventional phacoemulsification (phaco) in patients with coexisting cataract and open angle glaucoma. Twenty eyes were randomly assigned to either phaco-trab or phaco and followed for 12 months. Postoperatively, IOP decreased significantly in both groups, but patients with the combined procedure had fewer early IOP-elevations and significantly less medication. Visual acuity improved equally in the two groups.

Long-term astigmatic changes after phacoemulsification with single-stitch, horizontal suture closure.

We analyzed postoperative corneal astigmatism in 32 eyes followed for three years after small incision phacoemulsification with a 4 mm scleral tunnel incision and a single-stitch, horizontal suture technique. Sutures were left intact postoperatively. Mean surgically induced cylinder was 0.63 diopters (D) at one day postoperatively, -0.01 D at one year, and -0.07 D at three years. A significant number of eyes showed an initial shift toward with-the-rule astigmatism. At one year, the axis had nearly returned to preoperative orientation without further against-the-rule shift after three years. An uncorrected visual acuity of 20/40 or better was found in 43.8% of the patients at one week postoperatively and in 62.5% at one and three years. Best corrected visual acuity of 20/40 or better was found in 62.5%, 90.6%, and 93.7%, respectively.

Indications and efficacy of combined trabeculectomy and extracapsular cataract extraction with intraocular lens implantation in cataract patients with coexisting open angle glaucoma.

In an observational study 19 eyes with cataract and coexisting primary open angle glaucoma were scheduled to undergo combined procedure with ECCE-IOL and trabeculectomy. The aim of the present study was to investigate the results and the efficacy of combined surgery, when we extended the indication for surgery. Thus the surgical decision making was not based solely upon IOP readings, but also involved social/psychological factors. Median decrease in IOP (IOPpost-IOPpre) was significant through a 12-month observation period, p < 0.001. The number of medications dropped from 1.74 to 0.21, p < 0.01. Complication rate during operation and in the postoperative follow-up period was low. We conclude that it seems justified to extend the indication for combined surgery in cataract patients with coexisting open angle glaucoma in case of uncontrolled IOP, poor compliance, inability of sufficient medical care, or unacceptable medication. We recommend careful monitoring of the early postoperative IOP, even if hypotensive agents are given prophylactically.

Long-term natural and modified course of surgically induced astigmatism after extracapsular cataract extraction.

A prospective study was carried out to investigate the long-term course of surgically induced astigmatism after extracapsular cataract extraction. Sixty-one eyes were followed for 36 months. In 27 eyes with post-operative astigmatism > 4D with-the-rule, one or two sutures were cut in the steeper meridian after 3 months. In another group of 34 eyes with only minor or no postoperative astigmatism with-the-rule, no suture was cut. We found that 1) postoperative astigmatism was significantly increased in all eyes after 1 week and 3 months, but decreased in time approaching preoperative values after 3 years, 2) surgically induced astigmatism was with-the-rule at 1 week and 3 months but turned against-the-rule in time in both groups. Astigmatism decay rate was significantly steeper in eyes with suture cutting, 3) the keratometric axis was exclusively with-the-rule after 1 week, but turned against-the-rule in both groups, approaching the preoperative distribution of axis after 3 years. We concluded that surgically induced astigmatism is a dynamic feature showing changes in size and axis even in the period 1-3 years postoperatively. Suture cutting seems to intensify the decrease in the induced astigmatism and accelerate the shift in astigmatic axis, turning astigmatism against-the-rule compared to eyes with intact sutures.

The working positions of schoolchildren.

The survey described was carried out at a school in a Danish provincial town. During a one-week period, teachers recorded the various working positions of the schoolchildren. The positions recorded were those intended by the teachers. The average percentage of time allocated to physically active functions was generally acceptable. However, on average four of the classes were seated for more than 60 min without breaks, which is found to be inexpedient, medically as well as pedagogically. The time spent sitting is roughly distributed equally between backward-learning and forward-leaning positions: a fact to be remembered when designing school furniture for the future.

Analysis of the short-term effect of two viscoelastic agents on the intraocular pressure after extracapsular cataract extraction. Sodium hyaluronate 1% vs hydroxypropyl methylcellulose 2%.

We conducted a study to evaluate the shortterm effect on intraocular pressure (IOP) following extracapsular cataract extraction using either sodium hyaluronate 1% or hydroxypropyl methylcellulose 2%. In both groups a non-significant rise in IOP at day 1 was followed by a significant decline in IOP at day 3 to values below the pre-operative level (p < 0.05). At day 7 both groups had returned to pre-operative values. Post-operatively, spikes in intraocular pressure (> 25 mmHg) were seen equally in both groups. Patients with pre-operatively diagnosed open-angle glaucoma, high myopia and diabetic retinopathy are considered to be at high risk concerning post-operatively elevated IOP, but with small variation these patients followed the main trend.

Long-term results of extracapsular cataract extraction with posterior chamber lens implantation: sodium hyaluronate 1% vs hydroxypropyl methylcellulose 2%.

We investigated the frequency of surgical complications and the long-term outcome in terms of visual acuity, intraocular pressure and post-operative complications in 206 extracapsular cataract extraction procedures with posterior chamber lens implantation using either sodium hyaluronate 1% (Healon) or hydroxypropyl-methylcellulose 2% over a follow-up period of 12 months. We found no significant difference in the results of using either of the two viscoelastic agents.

[Back health of students]. / Skoleelevers rygsundhed.

The current knowledge of back symptoms among children and young people is sparse but studies indicate that their extent, at least among older pupils, resembles that in the adult age group. The design of school furniture, the sedentary way of life, the stressful practice of sports, and unsuitable gainful employment are some of the etiological factors. The dorsal health of schoolchildren is a field in great need of research and at the same time one with a great potential for prophylaxis.

Indications of trabeculectomy in open angle glaucoma.

The indications and frequency of trabeculectomy operations in Swedish eye clinics in 1980 and 1981 were assessed. The incidence of operations are significantly higher in the north than in the south of the country. The geographical influence was eliminated by excluding the 6 northernmost clinics, but the frequency of operations still varied with a factor of nearly 5 between the clinics. Most clinics seemed to allow individual modifications and exceptions to the rules of indication for surgery. An IOP surpassing a certain limit, locally fixed but varying greatly between clinics, was an indication in most places, even if the visual field was normal. An optic disc defect alone was an indication for surgery in one clinic only. In most clinics a progression of the glaucoma visual field defect with or without disc damage was an indication of surgical intervention.

The visual field after trabeculectomy. A follow-up study using computerized perimetry.

Series of visual fields in 20 eyes in which trabeculectomy had been performed were studied retrospectively. Computerized perimetry was used and the condition of the visual field was summarized into single numbers. Regression analysis was applied to series of such performance numbers. No correlation was found between the regression coefficient and the mean post-operative pressure or the mean pressure reduction. A dependence of the regression coefficient on the size of the visual field defect was observed.