Perioperative complications after cemented or uncemented hemiarthroplasty in hip fracture patients

BACKGROUND AND AIMS

Both cemented and uncemented hemiarthroplasties are acceptable methods for treating displaced femoral neck fractures. Cemented hemiarthroplasty has traditionally been recommended as being more safe and reliable. However, the cementing process carries a risk of fat embolism and cardiovascular problems. This study attempted to determine whether these complications can be avoided when using a modern uncemented stem.

MATERIAL AND METHODS

We retrospectively compared 222 hip fracture patients treated with hemiarthroplasty in our hospital. A total of 100 of these patients were treated with a hydroxyapatite-coated uncemented hemiendoprosthesis (Bi-Metric BFx) and 122 patients with a cemented hemiendoprosthesis (Lubinus SPII). Information on mortality and complications during the first 18.7 months was retrieved from patient files.

RESULTS AND CONCLUSIONS

Nine perioperative fat-embolic events were found in the cemented group and none in the uncemented group. During the initial hospital treatment, there were five deaths (4.1%) in the cemented group and one death (1%) in the uncemented group. There were significantly more perioperative fractures in the uncemented versus cemented group (7% versus 0.8%). We conclude that uncemented hemiarthroplasty is associated with more perioperative fractures than cemented hemiarthroplasty. However, perioperative cardiovascular disturbances may be less frequent with uncemented hemiarthroplasty, and early mortality may be lower with uncemented hemiarthroplasty.

Body mass index for athletes participating in swimming at the World Masters Games

AIM

Whilst there is growing evidence that physical activity across the lifespan is beneficial for improved health, there are many physiological changes involved with the aging process and subsequently the potential for reduced indices of health. The experimental aim was to gain improved understanding of the nexus between health, physical activity and aging by testing the hypothesis that prevalence of obesity (BMI ≥30 kg/m2) in the World Masters Games swimming cohort would be less than adult national populations.

METHODS

Body mass index (BMI) of 527 (49.7% male, 50.3% female) World Masters Games (WMG) swimmers aged 25-91 yrs (mean 54.3, standard deviation ±12.2) was investigated using a survey tool.

RESULTS

Analysis demonstrated significantly (χ2=44.9, P<0.001) reduced obesity (9% vs. 21%) when compared to the adult (aged ≥18years) Australian as well as other appropriate national populations. Investigation revealed, amongst other findings, that in line with trends shown in the adult Australian population, WMG male swimmers had a significantly higher BMI (mean 25.9 vs. 24.6) than their female counterparts (Z=-5.8, P<0.001).

CONCLUSION

Evidence of improved classification in one index of health (BMI ≥30 kg/m2) for WMG swimmers raised the possibility of improved classification due to adherence to sport or that reduced BMI was advantageous, contributing to this cohort competing at the WMG. This proportionately under-investigated population having reduced obesity over national populations was of particular interest given the obesity epidemic, the multi-faceted approaches taken globally in an attempt to halt this epidemic and a usual tendency for increased incidence of obesity with age.

Obesity has a negative impact on clinical outcome after total knee arthroplasty

BACKGROUND AND AIMS

Obesity has been linked to the development of osteoarthritis of the knee and since the incidence of obesity is increasing, the need for total knee arthroplasty (TKA) is likely to increase. Conflicting findings have been reported concerning the relationship between obesity and TKA. It has been shown in several studies, that obese patients have poorer clinical results after operation. On the other hand it has also been reported similar results for obese and non-obese patients. The purpose of this study was to analyze clinically and radiologically the results of total knee artrhoplasty in obese patients.

MATERIAL AND METHODS

The study consisted of 48 patients who had a TKA. The patients were divided in two groups according their body mass index. Patients of BMI over 30 were regarded as obese.

RESULTS

The obese patients had poorer clinical success at the final follow-up, their WOMAC scores were significantly higher compared to non-obese (pain 20.7 vs. 11.6; p = 0.021, stiffness 26.9 vs. 13.4; p = 0.006, physical function 26.5 vs. 14.4; p = 0.003). Differences were also found in the Knee (KS) and Function (FS) scores and a long-term postoperative ROM and (KS: 83.6 vs. 88.9; p = 0.01, FS: 63.6/76.3; p = 0.051, ROM: 104.6 vs. 109.6; p = 0.016). Non-obese patients reached better percentage improvement in the KSS compared to obese patients (KS change + 194.5% vs. + 59.5%, p = 0.03; FS change + 51.5% vs. + 14.9%, p = 0.19).

CONCLUSIONS

Obesity has a negative impact on the outcome of TKA, assessed by patients' clinical function and satisfaction level.

Obesity May Impair the Early Outcome of Total Knee Arthroplasty a Prospective Study of 100 Patients

Background and Aims:

Obesity has been linked to the development of osteoarthritis of the knee and increases the probability to fall into total knee arthroplasty. In this study we compared short-term outcome of total knee arthroplasty (TKA) in non-obese and obese patients.

Material and Methods:

A total of 100 patients underwent TKA between October 2006 and March 2007. They were divided into two groups based on the body mass index: 52 of the patients were obese (BMI ≥ 30 kg/m2) and 48 non-obese (BMI < 30 kg/m2). The short-term outcome was studied using clinical, functional and radiological analysis. The mean of the follow-up period was 3 months.

Results:

There were five complications (2 wound infections, phlebitis, nerve injury and massive edema) in obese patients group compared with no complications in non-obese (p = 0.028). The obese patients had also worse postoperative range of motion (110o̱ vs.118o̱, p = 0.001) than non-obese and the number of technical errors was 17 in obese and 5 in non-obese group, respectively (p = 0.007).

Conclusions:

We suggest that obesity may impair the early outcome of total knee arthroplasty and obese patients should be informed about the increased risk of complications related to TKA.

Multicenter dizygotic twin cohort study confirms two linkage susceptibility loci for body mass index at 3q29 and 7q36 and identifies three further potential novel loci

OBJECTIVE

To identify common loci and potential genetic variants affecting body mass index (BMI, kg m(-2)) in study populations originating from Europe.

DESIGN

We combined genome-wide linkage scans of six cohorts from Australia, Denmark, Finland, the Netherlands, Sweden and the United Kingdom with an approximately 10-cM microsatellite marker map. Variance components linkage analysis was carried out with age, sex and country of origin as covariates.

SUBJECTS

The GenomEUtwin consortium consists of twin cohorts from eight countries (Australia, Denmark, the Netherlands, Finland, Italy, Norway, Sweden and the United Kingdom) with a total data collection of more than 500,000 monozygotic and dizygotic (DZ) twin pairs. Variance due to early-life events and the environment is reduced within twin pairs, which makes DZ pairs highly valuable for linkage studies of complex traits. This study totaled 4401 European-originated twin families (10,535 individuals) from six countries (Australia, Denmark, the Netherlands, Finland, Sweden and the United Kingdom).

RESULTS

We found suggestive evidence for a quantitative trait locus on 3q29 and 7q36 in the combined sample of DZ twins (multipoint logarithm of odds score (MLOD) 2.6 and 2.4, respectively). Two individual cohorts showed strong evidence independently for three additional loci: 16q23 (MLOD=3.7) and 2p24 (MLOD=3.4) in the Dutch cohort and 20q13 (MLOD=3.2) in the Finnish cohort.

CONCLUSION

Linkage analysis of the combined data in this large twin cohort study provided evidence for suggestive linkage to BMI. In addition, two cohorts independently provided significant evidence of linkage to three new loci. The results of our study suggest a smaller environmental variance between DZ twins than full siblings, with a corresponding increase in heritability for BMI as well as an increase in linkage signal in well-replicated regions. The results are consistent with the possibility of locus heterogeneity for some genomic regions, and indicate a lack of major common quantitative trait locus variants affecting BMI in European populations.

Anosognosia after stroke: assessment, occurrence, subtypes and impact on functional outcome reviewed

PURPOSE

This review provides an update on recent research findings concerning the methods used in the assessment of anosognosia, the occurrence and subtypes of anosognosia, the association between anosognosia and neglect, and the impact of anosognosias on functional outcome.

METHODS

A systematic review covering the period from 1995 to 2005 was carried out on reports drawn from electronic databases (MEDLINE, PSYCHLIT) and identified from the references in these reports. Twenty-seven articles met the selection criteria.

RESULTS

The results of this review are in line with previous findings in the following respects: anosognosia was more often associated with right hemisphere damage, neglect and anosognosia co-occurred, and anosognosia had predictive value on poor functional outcome. The variation in the methods used in the assessment of anosognosia, patient samples and assessment times influence the occurrence rates and the predictive value of anosognosia, which might undermine the generalizability of the results.

CONCLUSIONS

More homogeneous patient samples and consistency in the assessment methods and evaluation times would facilitate comparisons of the occurrence and the impact of anosognosia on functional outcome. New methods need to be developed for the assessment of anosognosia. These new methods should take account of the subtypes of anosognosia both at verbal and at non-verbal levels.

Surgical treatment of ankle and foot fractures in the elderly

Ankle fractures are the most common lower extremity fractures. In younger age groups these fractures occur more often in men than in women, but after menopause there is a female predominance. Foot fractures show a similar trend. The primary goal in the treatment of ankle and foot fractures is to obtain exact reduction and stable fixation to facilitate early mobilization and good functional recovery. However, the need for internal fixation to secure fracture reduction must be weighed against the risk of operating on osteoporotic bone which lacks the strength to hold screws and plates. In the elderly, the preoperative evaluation of the peripheral blood supply is essential to avoid wound healing complications. We review here the surgical treatment of ankle and foot fractures with special reference to elderly patients.

Pedicled gastrocnemius flap in complicated total knee arthroplasty

BACKGROUND AND AIMS

The aim of this study was to evaluate the results of complicated total knee arthroplasty operations treated with radical wound revision and a pedicled gastrocnemius muscle flap.

MATERIAL AND METHODS

Retrospective analysis in a university hospital during a five-year-period.

RESULTS

Wound revision, debridement of the knee joint, replacing tibial plastics and a unilateral pedicled gastrocnemius muscle flap operation was performed to 10 patients after complicated total knee arthroplasty. After a median follow up time of 11.5 months 8/10 total knee arthroplasty joints were saved.

CONCLUSIONS

As much as 80% of patients could save their knee joint with this treatment protocol. Treatment of this problem needs good collaboration with orthopaedic and plastic surgeons.

Bone mineral density after the removal of intramedullary nails: a cross-sectional and longitudinal study

We measured bone mineral density (BMD) using dual X-ray absorptiometry (DXA) at several sites in both fractured and nonfractured limbs in eight patients with femoral shaft fracture and six with tibial shaft fracture at the time of the intramedullary (IM) nail removal. Seven patients were followed up for an average of 13 months. The BMD at the proximal part of the femur and tibia was from 3% to 11% lower in the fractured side as compared to the nonfractured side. The greatest bone loss (13%-21%) was found in the operated distal tibia of the patients with tibial shaft fractures. At the fracture site of the femur, BMD was 10.5% ( P < 0.05) higher, possibly owing to fracture callus formation, whereas tibial shaft BMD was not increased. However, a calculated apparent volumetric BMDvol at the fracture site was 15%-16% decreased. Although BMDs of the fractured side almost reached the baseline level of the nonfractured side (96.9%-102.1%) by the final follow-up (>12 months), the absolute deficit was still 3%-9%. Surprisingly, significant BMD increases (5%-6%) were also detected in all proximal femoral measurement sites of the contralateral limb, which indirectly suggests that the uninjured limb may also suffer from bone loss after lower-extremity trauma. We conclude that clinically important bone loss exists in the proximal femur and proximal and distal tibia of the fractured limb at the time of IM nail removal. Although areal BMD was higher at the femoral fracture site, the lower apparent volumetric BMDvol suggests decreased mineralization and reduced strength of the fracture site. Although the present results do not suggest special recommendations for restricted weight bearing after the removal of IM nails, the relationship between decreased bone density and increased risk of fractures should be borne in mind.

Percutaneous bone grafting in the treatment of the delayed union and non-union of tibial fractures

The classic method of open bone grafting in the treatment of un-united tibial fractures has been associated with some complications. A novel, minimally invasive, percutaneous technique of bone grafting is described. Forty-one consecutive patients with delayed union or non-union of a tibial fracture was treated with percutaneous bone grafting from 1993 to 1999. The mean age of the patients was 41 (15-86) years. Twenty-seven patients had grade I-III open fractures. The fractures had initially been treated in a cast (n=26), external fixator (n=14) or intramedullary nail (n=1). Two patients had an earlier unsuccessful Phemister-Charnley-type bone-grafting procedure for delayed union. The mean interval from injury to percutaneous bone grafting was 21 (13-66) weeks. Thirty-seven of the 41 un-united fractures healed in 13 (10-48) weeks after the percutaneous bone grafting. The mean hospital stay was 1 day. No infections, bleeding or neural complications existed. Percutaneous bone grafting appeared to be as effective as open techniques, and possessed considerable advantages. It is safe, time saving and economical, it involves minimal trauma at the fracture site and it avoids major donor site problems.

Intraindividual analysis of instantaneous heart rate variability

We examined the use and potential of quantifying instantaneous heart rate variability (HRV) using a joint time-frequency and time-domain methods. These new techniques are promising, because they provide tools to quantify nonstationary, beat-by-beat changes in HRV components, and are therefore flexible with respect to the design of experimental protocols. A smoothed pseudo-Wigner-Ville distribution (SPWVD) and a time-domain index using polynomial filtering produced fairly coherent estimates of band-specific HRV amplitudes, whereas SPWVD yielded additional information on the frequency characteristics of HRV. Instantaneous HRV appeared to have a complex and a frequency-specific relationship to cardiac activity and electrodermal activity, It is concluded that the time-frequency analysis of HRV is a very promising method for mapping transient changes in the frequency and amplitude characteristics of cardiac dynamics.

The fixation properties of carbon fiber-reinforced liquid crystalline polymer implant in bone: an experimental study in rabbits

A novel composite material with ultra-high strength and a low elastic modulus called carbon fiber-reinforced liquid crystalline polymer (LCP/CF) has been developed. We studied the fixation properties of an intramedullary LCP/CF rod in rabbit bone. The medullary canals of both femora were reamed with a drill 3.2 mm in diameter starting from the trochanteric fossa in eleven New Zealand White rabbits weighing on average 4.8 kg. A smooth LCP/CF rod 3.2 mm in diameter and 50 mm in length was introduced into the medullary canal of both femora. The follow-up intervals were 0, 6, 12, and 52 weeks. The upper part of the harvested femora was cut into two pieces, each 25 mm in length. A mechanical push-out test was performed within 48 h to determine bone-implant interface attachment strength in the proximal (cancellous) and distal (cortical) locations. The mean push-out strength values at 0, 6, 12, and 52 weeks were 61, 250, 382, and 612 KPa in the cancellous location and 0, 32, 41, and 68 KPa in the cortical location, respectively. The strength of the bone/implant interface appeared to be quite low, similar to other uncoated or nonporous implants, but it was found to increase with time.

Smoothing enhances the detection of common structure from multiple time series

The effects of smoothing (i.e., temporal averaging) on the detection of intraindividual interdependency from between-subjects aggregated (i.e., multiple) bivariate time series were examined. A simple moving average smoother was applied to different types of simulated processes that included error. The results indicated that smoothing facilitates the detection of common intraindividual structure from multiple time series. The efficacy of smoothing was dependent on the characteristics of the underlying process. It is suggested that smoothing increases the efficiency of the detection of common structure by increasing the signal-to-noise ratio (i.e., temporal reliability) of the time series. The issue and application of smoothing is further discussed in terms of signal extraction and classical test theory.

A comparison of different time series techniques to analyze phasic coupling: a case study of cardiac and electrodermal activity

This study examined the efficiency of different time series analysis techniques to extract information on the coupling of spontaneous phasic physiological responses. We compared four bivariate approaches, cross-spectral, cross-covariance, cross-covariance with prewhitening, and dynamic factor analysis, in their ability to yield unbiased estimates of (a) shared variance, (b) covariance, (c) strength of relationship, and (d) interchannel time-lag in empirical and simulated interbeat interval-electrodermal activity (IBI-EDA) time series. All methods produced similar estimates of the grand-averaged IBI-EDA dynamics, but only the measures of covariance produced reliable and unbiased estimates of the interindividual distribution of IBI-EDA coupling. We conclude that the extraction of phasic response patterns during continuous and unrestricted experimental situations may considerably facilitate psychophysiological research.

The relationship of respiratory sinus arrhythmia to the co-activation of autonomic and facial responses during the Rorschach test

We studied the relationship of respiratory sinus arrhythmia (RSA) to the co-activation of autonomic and facial expressive responses in 37 adult men during Rorschach testing. Interbeat interval (IBI), electrodermal activity, and facial electromyography were recorded continuously during the experiment. Prevailing mood and variability in the experience of valence and arousal were also measured. Bivariate intraindividual time series analysis was used to quantify spontaneously coupled phasic physiological responses. The results suggested that (a) spontaneous autonomic and expressive responses tend to parallel in time; (b) baseline, task-level, and task-induced change of RSA were positively related to coupled autonomic-expressive responses, a change in mood toward a more energetic state, and a tendency to have more variability in the emotional experience during the task; and (c) especially cardiac-expressive response coupling was related to mood change. It is concluded that the vagal system is related to the control of facial muscle activity and may mediate both tonic and phasic emotion-related changes in IBI. The role of phasic intraindividual response patterns in emotional and social behavior is highlighted.

Inhibited and disinhibited temperament and autonomic stress reactivity

We examined the relationship of temperament dimensions serving as markers for Gray's behavioral activation system (BAS) and behavioral inhibition system (BIS) with autonomic stress reactivity in 35 middle-aged men. Temperament was measured using the Strelau Temperament Inventory--Revised. Skin conductance responses and inter-beat interval were measured during administration of the Rorschach test. The results showed that temperamental activation was positively related to the task-level of and task-induced change in respiratory sinus arrhythmia (RSA) amplitude, but unrelated to heart rate (HR) reactivity. Temperamental inhibition was negatively associated with the task-level of electrodermal activity and task-induced change in RSA amplitude, and positively associated with HR reactivity. The findings are in part contrary to the hypotheses presented in the literature. They also suggest that the temperamental inhibition-HR reactivity relationship is mediated by the parasympathetic nervous system.

Dislocation of the proximal tibiofibular joint.A new method for fixation

We introduce a new method for fixation of a rare, isolated, proximal tibiofibular dislocation. One third of the biceps femoris muscle tendon was used for fixation of the dislocated proximal fibular head. The fixation was achieved by using a soft threaded interference ACL screw.

Fixation of distal femoral osteotomy with an intramedullary rod: early failure of carbon fibre composite implant in rabbits

A novel composite material with an ultra-high strength and a low elastic modulus, comprising a carbon fibre reinforced liquid crystalline polymer (LCP/CF) has been developed. An experimental osteotomy of the distal femur in nineteen rabbits weighing on average 4.8 (3.7-6.3) kg was fixed with an intramedullary LCP/CF rod of 3.2 mm in diameter and 50 mm in length. The initial mechanical properties of the rods had a mean shear strength of 180 MPa, a flexural strength of 450 MPa, and a flexural modulus of 40 GPa. The rods were implanted for periods of 3, 6, 12, 24, and 52 weeks. The healing of the osteotomy was analyzed by radiographic, histological, microradiographic, and oxytetracycline fluorescence studies. The strength retention of the LCP/CF rods was measured by mechanical testing. Solid union of the osteotomy was seen within 6 weeks. The implants retained their original strength properties up to 52 weeks. In three rabbits, a non-union with granulation tissue and carbon fibre particles was noticed at the osteotomy site, where disruption of the implant surface was seen at the level of the osteotomy. Further studies with a special interest in the fabrication process of the LCP/CF-implants are needed.

Endoprosthetic treatment of displaced femoral neck fractures in the year 2000

Endoprosthetic treatment of intracapsular, subcapital displaced femoral neck fracture in the elderly patients is widely accepted. According to increase in total number of femoral neck fractures in the last decades, there will be about 5 500 femoral neck fractures in Finland suitable for endoprosthetic treatment in the year 2020. Uncemented or cemented unipolar, bipolar or total hip replacements have been alternatives to internal fixation. For active elderly patients with a much younger physiologic than actual age and living a fully independent life, cemented bipolar or total hip arthroplasty should be preferred to unipolar arthroplasty in the year 2 000.

Fixation of femoral shaft osteotomy with an intramedullary composite rod: an experimental study on dogs with a two-year follow-up

A novel composite material with an ultra-high strength and a low elastic modulus called carbon fibre-reinforced liquid crystalline polymer (LCP/CF) has been developed. An experimental diaphyseal osteotomy of the proximal femur in fourteen Beagle dogs was fixed with an intramedullary LCP/CF rod of 4.5 mm in diameter and 80 mm in length. The radiological follow-up intervals were 1, 3, 6, 12, 24, 52, and 104 weeks. Five dogs were killed at 1 year and three dogs at 2 years for histological studies; six dogs were retained for longer follow-up. Radiographs showed an uncomplicated healing of the diaphyseal osteotomy with an external callus formation in all dogs in 12 weeks. Histological analysis revealed a benign host tissue response with few inflammatory cells. Both bone and fibrous tissue were seen at the LCP/CF-host tissue interface. The cross-sectional cortical area of the operated femur was slightly greater than that of the control femur in the 2-year follow-up. LCP/CF showed promising properties for high-load applications.

Proliferation potential of human lumbar disc after herniation

To investigate the regenerative potential of human disc tissue, the disc samples were obtained during surgery from 24 adult patients with first lumbar prolapses and from 14 patients with recurrent lumbar prolapses. Preoperative magnetic resonance imaging (MRI) confirmed prolapse and disc degeneration in all cases. The proliferation activity of the sampled connective tissue cells was studied with the immunohistochemical expression of Ki-67(MIB-1) antigen. The antigen was positive in 6 of 24 (25%) specimens from first prolapse and in none of the 14 specimens from the recurrent prolapse. The amount of proliferative cells did not correlate to the degree of disc degeneration in MRI. Our results indicate that connective tissue cells in adult degenerative disc may show proliferation activity after the first herniation and thus regenerative potential. The enhanced matrix proliferation may not be a significant reason for recurrent prolapses because none of the recurrent disc specimen showed proliferation activity.

The effect of an intramedullary carbon-fiber-reinforced liquid crystalline polymer implant on bone: an experimental study on rabbits

A novel composite material with an ultra-high strength and a low elastic modulus called carbon-fiber-reinforced liquid crystalline polymer (LCP/CF) has been developed. We studied the effects of an intramedullary LCP/CF rod on bone in rabbits. A LCP/CF rod of 3.2 mm in diameter and 50 mm in length was introduced into the intramedullary canal of the right femur in ten rabbits weighing an average of 3.6 (3.1-4.2) kg. The follow-up intervals were 3 and 52 weeks. No signs of deformity or osteopenia were seen in the operated femurs in the radiographic, histological, and histomorphometric studies. Histologically, the implant was enclosed by cancellous bone in the metaphyseal area and by a thin cancellous bone cuff in medullary cavity. Bone was able to grow in direct contact with the LCP/CF rod. No signs of degradation of the implants or of adverse tissue reaction were seen. The intramedullary LCP/CF rod had no harmful effects on bone in rabbits. The biocompatibility of the LCP/CF appeared to be good. This novel composite material demonstrates properties that may be useful in orthopedic applications.

The synchronization of electrodermal activity and heart rate and its relationship to energetic arousal: a time series approach

We examined the synchronization between indices of autonomic nervous system (ANS) function and its relation to multiple measures of arousal in 37 middle-aged men. Electrodermal activity (EDA), heart rate (HR), and subjective and behavioral arousal were measured during administration of the Rorschach test. Prevailing mood and depression were also measured. The relationship between phasic EDA and HR activity was assessed by constructing within-subjects time series models. The results showed that phasic EDA and HR accelerations were synchronized, while there was no association between tonic EDA and HR in between-subjects analysis. In addition, EDA-HR synchronization was positively associated with verbal activity, variability of arousal experience, and activation mood, and negatively associated with depression. It is suggested that within-subjects analysis of physiological time series data can further our understanding of the individual differences in ANS function and on the correlates of effector organ synchronization.

Mechanical properties and strength retention of carbon fibre-reinforced liquid crystalline polymer (LCP/CF) composite: an experimental study on rabbits

A novel composite material with ultra-high flexural strength and cortical-bone-matched elastic modulus made of liquid crystalline polymer reinforced with carbon fibres (LCP/CF) is described. Cylindrical rods of 3.2 mm diameter and 50 mm length were fabricated by a preimpregnation/pultrusion method. The initial mechanical properties of the LCP/CF rods were as follows: flexural strength 448 MPa, flexural modulus 43 GPa, shear strength 164 MPa, and interlaminar shear strength 15.3 MPa. In the in vitro study the LCP/CF rods were immersed in phosphate-buffered saline of 37 degrees C for 12, 24, and 52 weeks. In the in vivo study the LCP/CF rods were implanted into the medullary cavity of both femora and subcutaneous tissue of the New Zealand White rabbits for 12, 24, and 52 weeks. The flexural strength of the LCP/CF rods at 52 weeks was 463 MPa in saline, 467 MPa in the subcutaneous tissue and 466 MPa in the medullary cavity of the femur. The flexural modulus was 44.6, 48.9 and 46.2 GPa, respectively. The corresponding shear strength values were 160, 178 and 181 MPa. We conclude that the LCP/CF is a promising material for high-load applications and the LCP/CF rods retain their initial mechanical properties in one-year follow-up in vivo and in vitro.

Are serum inflammatory markers age dependent in acute appendicitis?

BACKGROUND

Preoperative measurement of body inflammatory agents reduces unnecessary appendectomies by up to 30 percent. A decline in the formation of blood leukocytes and C-reactive protein with aging may hinder the correct diagnosis of appendicitis.

STUDY DESIGN

White cell count and C-reactive protein were determined before appendectomy in 600 patients aged 0 to 5 years, 6 to 19 years, 20 to 39 years, 40 to 59 years, 60 to 79 years, and older than 80 years. Their records were analyzed. The sensitivity, specificity, diagnostic accuracy, and receiver-operating characteristic curves for C-reactive protein and white cell count to predict appendicitis were calculated separately for each age group.

RESULTS

The rates of negative explorations and perforations were highest at both extremes of age. In uncomplicated appendicitis, the diagnostic potential of white cell count was better than C-reactive protein in all age groups except infants. The C-reactive protein was elevated similarly throughout human life, but only in those with perforated appendicitis. The receiver-operating characteristic curves confirmed that the performance of white cell count was better than C-reactive protein in the correct diagnosis in every age group except infants and octogenarians.

CONCLUSIONS

The leukocyte response declines in 0- to 5-year-old children with appendicitis, but the C-reactive protein response is well preserved in all other age groups.

Knee osteoarthritis in former runners, soccer players, weight lifters, and shooters

OBJECTIVE

To determine the relationship between different physical loading conditions and findings of knee osteoarthritis (OA).

METHODS

We selected 117 male former top-level athletes (age range 45-68 years) who had participated in sports activities with distinctly different loading conditions: 28 had been long-distance runners, 31 soccer players, 29 weight lifters, and 29 shooters. Histories of lifetime occupational and athletic knee loading, knee injuries, and knee symptoms were obtained, and subjects were examined clinically and radiographically for knee findings of OA.

RESULTS

The prevalence of tibiofemoral or patellofemoral OA based on radiographic examination was 3% in shooters, 29% in soccer players, 31% in weight lifters, and 14% in runners (P = 0.016 between groups). Soccer players had the highest prevalence of tibiofemoral OA (26%), and weight lifters had the highest prevalence of patellofemoral OA (28%). Subjects with radiographically documented knee OA had more symptoms, clinical findings, and functional limitations than did subjects without knee OA. By stepwise logistic regression analysis, the risk for having knee OA was increased in subjects with previous knee injuries (odds ratio [OR] 4.73), high body mass index at the age of 20 (OR 1.76/unit of increasing body mass index), previous participation in heavy work (OR 1.08/work-year), kneeling or squatting work (OR 1.10/work-year), and in subjects participating in soccer (OR 5.21).

CONCLUSION

Soccer players and weight lifters are at increased risk of developing premature knee OA. The increased risk is explained in part by knee injuries in soccer players and by high body mass in weight lifters.

Emergency abdominal surgery in the elderly

We reviewed 201 consecutive patients aged over 65 years who were operated on for acute abdomen during the period 1986-89. Emergency procedures were most commonly performed on the biliary tract (24%), the appendix (20%), bowel (15%) and abdominal wall (12%). The postoperative morbidity was 26%, and the mortality rate of 22% was related most commonly to mesenterial thrombosis and intestinal obstruction. In fatal cases, 44% of the patients were over 80 years old and 64% were placed into the ASA classes IV-V. Eighty-four patients (42%) underwent postoperative intensive care, and 22 re-operations (9.0%) were performed. The mean hospital stay was 12 days and 70% of patients returned home after surgery. In conclusion, the outcome of emergency abdominal surgery in patients under 80 years of age and with no serious co-existing diseases has improved. Very old patients in ASA classes 4-5 still have a poor outcome.

Emergency appendectomies in patients over 80 years

The outcome of 100 consecutive emergency appendectomies between 1985 and 1991 in octogenarians was compared to an unselected group of equal size, composed of patients between 60-79 and under 59 years. The frequency of appendectomies in the elderly did not increase during the study period. Negative explorations were performed in 28%-33% of the three age groups. The mortality was 0%, 3%, and 7%, and the complication rates 10%, 23%, and 40% in the patients aged under 59, between 60-79, and over 80 years, respectively. Appendiceal perforation was found in 49% of octogenarians, and it was associated with the mortality rate of 21%. In conclusion, patients under 80 years with emergency appendectomy had acceptable low mortality and morbidity rates that were comparable to the results of elective abdominal surgery of the same age, but the octogenarians had higher risk of poor outcome.

Clinical value of serum tumour markers TPA, TPS, TAG 12, CA 15-3 and MCA in breast cancer diagnosis; results from a prospective study

The aim of this study was to assess the clinical value of five serum tumour markers, TPA, TPS, TAG 12, CA 15-3 and MCA, in the diagnosis of breast cancer. The serum values were measured in a prospective series of patients with breast cancer (n = 82) and benign breast disease (n = 25). The cut-off levels (90% specificity) determined for each test were 109.0 U/1 for TPA, 156.0 U/1 for TPS, 52.5 kU/1 cut-off level for TAG 12 and 24.9 kU/1 cut-off level for CA 15-3, and at the 12.0 kU/1 cut-off level for MCA. Using these cut-off levels the diagnostic sensitivity of the TPA test was 0.23, for the TPS test 0.15, 0.44 for the TAG 12 test, 0.13 for the CA 15-3 test and 0.10 for the MCA test in detecting breast cancer. When the cut-off levels were determined at 95th percentile level for each test, the cut-off level for TPA was 143.0 U/1, 279.0 U/1 cut-off level for TPS, 105.0 kU/1 cut-off level for TAG 12 and 36.7 kU/1 cut-off level for CA 15.3, and at the 15.3 kU/1 cut-off level for MCA. Using these cut-off levels the diagnostic sensitivity of the TPA test was 0.12, 0.01 for the TPS test, 0.06 for the TAG 12 test, 0.06 for the CA 15-3 test and 0.06 for the MCA test in detecting breast cancer. The correlation coefficients in breast cancer patients between TPA and TPS measurements was 0.82, between TPA and TAG 12 measurements it was 0.09, between TPA and CA 15-3 measurements it was 0.08, and 0.11 between TPA and MCA measurements. None of the serum markers studied were significant predictors in breast cancer diagnosis in a logistic regression analysis or in the discriminant analysis. Thus it seems that TPA, TPS, TAG 12, CA 15-3 and MCA have only limited value in breast cancer diagnosis, but their role in the follow-up and prediction of prognosis of breast cancer patients is a subject for further investigation.

Evaluation of a real-time monitoring system for river quality - a trade-off between risk attitudes, costs, and uncertainty

Uncertainty is definitely one of the key topics in environmental assessment and management. Typically, attempts to reduce uncertainty are subject to expenses. But how to compare and trade-off expenses and the reduced uncertainty? They only seldom allow the use of a single unit. Instead, the whole analysis and decision procedure is very subjective. This paper presents one approach to handle such problems, namely the combined use of Bayesian influence diagrams, and probabilistic risk attitude analysis. The approach was used in the evaluation of three alternatives for a real time river water quality forecasting system. A trade-off analysis of risk attitudes, costs and uncertainty indicated the levels of socioeconomic utility required for investments in the respective systems, and accordingly illuminated the impact of the uncertainties involved on inference and decision-making with various risk attitudes and discount rates.

Spontaneous peripelvic extravasation of urine as a cause of acute abdomen

In eight patients with sudden onset of flank pain, urography showed extravasation of urine. The cause of peripelvic leakage was verified ureteral stone in four cases, stricture of the ureteropelvic junction in one, and unknown in three cases. Treatment was symptomatic in four cases, drainage in two and surgery in two cases. Seven patients recovered uneventfully, but one required nephrectomy. The prognosis in spontaneous urinary extravasation is usually good without drainage. Open surgery is seldom indicated.

A real-time monitoring system for Kerava river quality

The hygienic quality of the water of the Kerava river, southern Finland, deteriorates occasionally. The purpose of the study was to design a real-time monitoring system that would inform the public using the river for recreational purposes about the changes in water quality. The system was constrained to consist of on-line sensing of water quality and quantity, and adjacent forecasting models. Four different system alternatives were analyzed and compared. The first alternative observes river flow in real-time; the second alternative also monitors water temperature, turbidity, pH, conductivity and dissolved oxygen. The data collected in this way are used to forecast Streptococcus and E. coli concentrations, using canonical correlation and regression analysis. The third configuration is a two-step procedure, where river flow is first predicted by an ARMAX model and the hygienic state is then based on the flow estimate, as in the first assemblage. The most expensive monitoring system, which at present is the least well-known, is to apply the Lidar system, where the hygienic status of the river quality is observed directly using laser technology, placing less emphasis on modeling. In this paper, the alternatives are formulated and a preliminary comparison is made, using the criteria of operational feasibility, prediction uncertainty, investment and maintenance costs, and suitability for in-situ monitoring.

Phenolic glycosides govern the food selection pattern of willow feeding leaf beetles

The relationship between the food selection of four leaf beetle species (Phratora vitellinae, Plagiodera versicolora, Lochmaea capreae, Galerucella lineola) and the phenolic glycosides of willow (Salix spp.) leaves was tested in laboratory food choice experiments. Four willow species native to the study area (Eastern Finland) and four introduced, cultivated willows were tested.The willow species exhibited profound differences in their phenolic glycoside composition and total concentration. The food selection patterns of the leaf beetles followed closely the phenolic glycoside spectra of the willow species. Both the total amount and the composition of phenolic glycosides affected the feeding by the beetles. Phenolic glycosides apparently have both stimulatory and inhibitory influences on leaf beetle feeding depending on the degree of adaptation of a particular insect. Very rare glycosides or exceptional combination of several glycoside types seem to provide certain willow species with high level of resistance against most herbivorous insects. Analogously the average absolute amount of leaf beetle feeding was lower on the introduced willows than on the native species to which the local herbivores have a good opportunity to become adapted.