Search PubMed⌕ Search

Biomedical subjects

Olof Johnell

Publications and source records attributed to Olof Johnell.

At least 55 records · Page 3Linked to original sources
PubMed2003

Economic implication of osteoporotic spine disease: cost to society.

The costs of vertebral fractures are less well defined than the costs of hip fractures. Large studies are urgently needed. From the data that exist, vertebral fractures have a higher cost than previously expected: for hospitalized fractures in a US study, USD 10 000 per year without rehabilitation costs, for all clinical fractures USD 2000 the first year, and in a Swedish study slightly more. These new data on the cost of vertebral fractures will have an impact on health economy calculations. In the future it may be be cost-effective only to prevent vertebral fractures.

Aged↗
PubMed2003

Bone loss and bone size after menopause.

BACKGROUND: Bone loss increases after menopause. However, bone strength also depends on structural characteristics such as bone size. Whether bone size increases as a result of periosteal apposition and whether a strength index accounting for both bone density and bone size might predict the risk of fracture better than bone density alone are unclear. METHODS: Bone mass and the skeletal structure of the distal radius were evaluated by single-photon absorptiometry every other year in 108 women, all of whom were followed from the time of menopause for a mean period of 15 years. Postmenopausal serum estradiol levels and fractures of the distal radius were noted. RESULTS: The mean (+/-SD) annual decrease in bone mineral density was 1.9+/-0.7 percent. The medullary bone diameter increased annually by 1.1+/-0.9 percent, and the periosteal diameter by 0.7+/-0.3 percent; the strength index decreased by 0.7+/-0.7 percent. The expansion of the medullary diameter and the expansion of the periosteal diameter were correlated with one another (r = 0.54, P<0.001), and women in the highest quartile of medullary expansion had more loss of bone mineral density and greater periosteal apposition than women in the lowest quartile (P<0.001 for both comparisons). The postmenopausal serum estradiol level was correlated with changes in the periosteal diameter (r = -0.25, P=0.009) and with changes in bone mineral density (r = 0.34, P<0.001). A 1-SD decrement in the strength index at base line was associated with a risk ratio for fracture of the distal radius of 3.8 (95 percent confidence interval, 1.8 to 8.0). CONCLUSIONS: Increased bone loss after menopause is associated with increased periosteal apposition, which partially preserves bone strength. A strength index may be a helpful predictor of the risk of fracture.

Biomechanical Phenomena↗
PubMed2003

The role of osteophytic growth in hip osteoarthritis.

We studied the appearance and frequency of the medial epiarticular osteophyte in human femoral heads. Specimens were sampled from 24 men and 31 women who underwent total hip arthroplasty. On radiography, medial epiarticular osteophytes were present in two thirds of the cases. However, histological examination revealed endochondral ossification in all. Presumably, the bone formation was preceded by the formation of canals and cavities containing vessels. Due to the ossification around these canals and cavities, the histological picture frequently featured two layers of cartilage with bone in the middle. Also in the marginal osteophytes, bone was formed by endochondral ossification. However, this bone appeared more irregular. The new bone formation most likely indicates a reactivated growth as an attempt to repair the osteoarthritic lesions rather than a process of degradation.

Aged↗
PubMed2003

Incidence of hospitalized osteoporotic fractures in cohorts with high dietary intake of persistent organochlorine compounds.

OBJECTIVES: Environmental factors might be of importance for the dramatically increasing incidence of osteoporotic fractures. Persistent organochlorine compounds (POCs) have, in animal studies, impaired normal bone metabolism and resulted in increased bone fragility. The goal of this study was to assess whether a high dietary intake of POCs through fatty fish from the Baltic Sea may result in an increased incidence of osteoporotic fractures. METHODS: Fishermen and their wives from the Swedish east coast on the Baltic Sea (exposed) and west coasts (unexposed) constituted the study base. Information on vital status and hospitalization of persons with fractures from 1987 to 1996, classified according to the ninth revision of the International Classification of Diseases, was retrieved for 17,823 subjects through register linkages. The impact of coastal stretch on fracture incidence was assessed by Poisson regression models, with age and calendar year also being taken into account. RESULTS: There was a significantly increased incidence rate ratio (IRR: 2.29, 95% confidence intervals (CI): 1.23-4.28) for vertebral fractures among east-coast women, and a similar, but non-significant, similar tendency in men (IRR 1.45, 95% CI 0.74-2.84). Such cohort differences were not seen for any other fracture type. CONCLUSIONS: The results give some indirect support for the notion that a high dietary intake of POCs through fatty fish from the Baltic Sea might be a risk factor for vertebral fractures, but it cannot be excluded that confounding from differences in smoking habits might explain part of the observed effects. To clarify this, detailed individual information on exposure and potential confounders has to be ascertained.

Animals↗
PubMed2003

Bone morphology in relation to the migration of porous-coated anatomic knee arthroplasties : a roentgen stereophotogrammetric and histomorphometric study in 23 knees.

The quality of the subchondral bone in total knee arthroplasty (TKA) may be important for the outcome. We correlated a histomorphologic analysis of the prosthetic bone bed to micromotion as analyzed by roentgen stereophotogrammetric analysis (RSA). Twenty-three knees, both osteo- and rheumatoid arthritic were studied. The mean migration after 1 year was 1 mm (0.21-2.68), with no correlation to the bone variables or diagnosis. One patient underwent revision after 3 years because of pain. One patient underwent revision after 15 years because of aseptic loosening. This patient appeared stable according to changes in maximum total point motion (MTPM), but the prosthesis migrated continuously according to segment motion. Prosthetic migration increased after 10 years, zones started to evolve, and the patient became symptomatic after 13 years. A biopsy of the bone bed was taken in all patients. A larger percentage of trabecular bone and a larger relative area of unmineralized osteoid surface were found in patients with rheumatoid arthritis compared with those with osteoarthritis. The latter finding is probably a result of increased bone turnover. In conclusion, no support currently exists for the idea that preoperative bone quality, evaluated as bone histomorphometry, has any impact on prosthetic micromotion in knee prostheses.

Adult↗
PubMed2003

Effect of raloxifene on the risk of new vertebral fracture in postmenopausal women with osteopenia or osteoporosis: a reanalysis of the Multiple Outcomes of Raloxifene Evaluation trial.

Raloxifene reduces vertebral fracture risk in postmenopausal women with osteoporosis and established osteoporosis, but its efficacy in women with osteopenia has not been studied. The objective of this study was to evaluate the effect of raloxifene hydrochloride on the risk of vertebral fractures in postmenopausal women with osteopenia and to compare this effect with that in women with osteoporosis as defined by the bone mineral density (BMD) T-score at the hip. We studied the 3204 postmenopausal women with osteopenia or osteoporosis without vertebral fractures at baseline in the Multiple Outcomes of Raloxifene Evaluation trial. Compared with placebo, 60 mg/day raloxifene reduced the risk of new vertebral fractures at 3 years independent of baseline total hip BMD. The relative risk for new vertebral fractures for the raloxifene group compared with placebo was 0.53 (95% CI, 0.32-0.88) for those with osteopenia and 0.31 (0.06-0.71) for those with osteoporosis. In raloxifene-treated women the rate of vertebral fracture was similar in women with osteoporosis (2%) to that in women with osteopenia (1.9%). For clinically apparent vertebral fractures, the relative risk of fracture in the osteopenia group for raloxifene was 0.25 (0.04-0.63) compared with placebo. There were no new clinical vertebral fractures in women with osteoporosis receiving raloxifene, whereas four occurred in the placebo group. We conclude that treatment with 60 mg/day raloxifene significantly decreases the risk of new vertebral fractures and new clinical vertebral fractures in postmenopausal women without baseline vertebral fracture who have osteopenia or osteoporosis.

Aged↗
PubMed2003

Is there an association between inhaled corticosteroids and bone density in postmenopausal women?

BACKGROUND: During the last decades, there has been increased concern about the association between oral corticosteroid (OC) therapy and osteoporosis. OBJECTIVE: The question currently discussed is whether inhaled corticosteroids (ICs) in recommended doses have any clinically relevant effects on bone mineral density (BMD). METHODS: We compared BMD in postmenopausal women exposed to corticosteroids only in inhaled form (IC group, n = 106) with that in women not exposed to corticosteroids (unexposed group, n = 674). BMD was also studied in 49 women exposed to OCs, intra-articular injections, or both in addition to ICs (OC group). The women were recruited from a population-based prospective cohort study. METHODS: We used a dietary survey, bone density measurement of the forearm, and a health questionnaire including an interview about past and present medication use. RESULTS: Mean BMD did not significantly differ between the IC group (0.434 g/cm2) and the unexposed group (0.429 g/cm2). The mean duration and dose of ICs was 8.2 +/- 5.03 years and 853 microg daily. Within the IC group, BMD stratified for cumulative dose of IC, duration, or current dose greater than or less than 1000 microg did not differ. BMD in the OC group was lower than that in the IC group (0.408 vs 0.434 g/cm2). CONCLUSION: No difference in BMD was noted between the IC group and unexposed control subjects, nor was any dose-response relationship observed between IC therapy and BMD.

Administration, Inhalation↗
PubMed2003

Costs of internal fixation and arthroplasty for displaced femoral neck fractures: a randomized study of 68 patients.

We included in a prospective, randomized study 68 patients aged 70 years or older, with displaced cervical hip fractures. The patients were randomized to internal fixation with hook-pins (36) or primary arthroplasty (32) (total or hemiarthroplasty due to their prefracture status) and followed for 2 years. Patients with rheumatoid arthritis, mental confusion and/or residence in an institution were excluded. The postoperative stay in hospital, rehabilitation wards or nursing homes were recorded as well as complications and the costs of surgery. The aim of this study was to compare the accumulated costs of each method, during the first 2 years after the fracture. In the internal fixation group, 15/36 were considered failures, as compared to 1/32 in the arthroplasty group. As regards primary treatment of the fracture, the durations of surgery and hospital stay were shorter after internal fixation, but the total need for hospitalization/institutionalization was somewhat longer in these patients. The mean 2-year cost for a patient with internal fixation was USD 21,000 and of one with primary arthroplasty USD 15,000. We conclude that primary arthroplasty is a cost-efficient treatment. Considering the very much higher failure rate after internal fixation--leading to increased suffering for these patients--primary arthroplasty stands out as the best method for displaced fractures of the femoral neck.

Aged↗
PubMed2003

Effects of specific post-menopausal hormone therapies on bone mineral density in post-menopausal women: a meta-analysis.

BACKGROUND: Long-term post-menopausal hormone therapy (pHT) was often regarded as first-line therapy to prevent fractures in post-menopausal women, a recommendation under scrutiny given the benefit-risk profile of the Women's Health Initiative results of the estrogen-progestin combination. Apart from controlled clinical studies providing data with fractures as an end point, measures of lumbar and hip bone mineral density (BMD) may be used to assess bone-related effects of pHT. The objective of this study was to conduct a systematic review of 2-year trials, published between 1990 and December 2002, and assessing changes in BMD by any estrogen including ethinyl estradiol, any estrogen plus any progestin, or tibolone. METHODS: We searched MEDLINE, EMBASE and systematic reviews. Thirty-nine randomized, prospective, controlled 2-year trials were analysed in pre-specified groups according to the profile of the compounds. RESULTS: Virtually all pHT regimens at least maintain BMD at the lumbar spine and the hip compared with baseline; there is no apparent difference between the various estrogenic compounds. Tibolone, a synthetic progestin, appears to be as effective as any estrogen. Most trials were conducted in early post-menopausal women, fewer in women with hysterectomy and/or bilateral oophorectomy. CONCLUSIONS: The size of impact on BMD does not appear to differ between tibolone and any estrogen compound studied.

Adult↗
PubMed2003

Cost effectiveness of alendronate (fosamax) for the treatment of osteoporosis and prevention of fractures.

BACKGROUND: The Fracture Intervention Trial (FIT) demonstrated that the bisphosphonate alendronate reduces the risk of hip, spine and wrist fracture in osteoporotic women by approximately one half. OBJECTIVE: To use data from FIT to conduct a cost-effectiveness analysis of alendronate. DESIGN: A Markov model was developed for a cohort of Swedish women, comparable in relative fracture risk to the women enrolled in the FIT vertebral fracture arm (i.e. age 71 years with low bone mass plus at least one prior spine fracture). The women in the model (with low bone mass and a previous spine fracture) were exposed to alendronate therapy and transitioned over time from a 'well' health state to health states of 'hip fracture', 'spine fracture', 'wrist fracture' or 'death'. All costs were calculated in 2000 Swedish kronors (SEK). TIME HORIZON: In the Markov model our base-case treatment duration was 5 years followed by a 5-year period where the benefit declined linearly to 0. RESULTS: We found that treating 71-year-old osteoporotic women with a prior spine fracture with alendronate resulted in a cost per quality-adjusted life-year (QALY) gained of SEK76000, which is well below the threshold for cost effectiveness of SEK300000. For women aged 65 years, the cost-effectiveness ratio increased to SEK173000 and for women aged 77 years, the cost-effectiveness ratio decreased to SEK52000. CONCLUSIONS: Treating older osteoporotic women with alendronate was more cost effective than treating younger women with osteoporosis, and treating osteoporotic women with prior spine fracture was more cost effective than treating osteoporotic women without prior spine fracture. However, the costs per QALY gained for all populations studied were below generally accepted thresholds for cost effectiveness.

Age Factors↗
PubMed2002

Non-participants differ from participants as regards risk factors for vertebral deformities: a source of misinterpretation in the European Vertebral Osteoporosis Study.

Interpretation of data in epidemiological cohort studies may be confounded if differences exist between non-participants and participants. In the Malmö part of the European Vertebral Osteoporosis Study (EVOS), which was designed to evaluate the prevalence of vertebral deformity in 50-80-year-old persons, we compared 74 men and 95 women who had been invited, but declined to participate with age- and gender-matched participants as regards alcohol abuse, previous fractures and subsequent mortality, factors known to affect the prevalence of vertebral deformity. We found more men with alcohol abuse, more men with a previous fragility fracture and a tendency to more men with a previous clinical vertebral fracture among the non-participants than in the male participants. In contrast, there were fewer female non-participants than female participants with a previous clinical vertebral fracture. The mortality rate during the decade after the baseline examination was higher among both male and female non-participants. The "true" prevalence of vertebral deformity in the whole male population at risk in Malmö seems to be underestimated in the EVOS study. In women, it is more difficult to estimate the combined result of the confounding factors. Conclusions based on the EVOS participants may not be applicable to the whole population at risk.

Aged↗
PubMed2002

The epidemiology of total hip replacement in The Netherlands and Sweden: present status and future needs.

By combining data from the Discharge registers and the census bureaus in The Netherlands and Sweden, we calculated the age-specific incidences of primary total hip replacement (THR), studied the demographic profile of the population receiving THR and predicted demands. In the period 1986-1997, the number of THRs increased by 20% in Sweden to 10,000 operations (113/100,000 inhabitants) and by 68% to 17,400 operations (112/100,000 inhabitants) in The Netherlands. Of this increase 3% and 15% could be explained by changes in the age-profile and size of the population, respectively. Although the overall incidence of THR was similar in both countries in 1997, we found that, after correction for differences in population structure, the incidence of THR was 20% higher in The Netherlands. In Sweden, relatively more men were operated on than in The Netherlands. We also found that in Sweden, but not in the Netherlands, relatively more older people were operated on in 1997 than in 1987. Assuming no further change in the age- and sex-specific arthroplasty rates, the predicted annual number of total hip replacements by the year 2020 will increase by at least one fourth in Sweden and almost one half in The Netherlands.

Adult↗
PubMed2002

Primary hemiarthroplasty in old patients with displaced femoral neck fracture: a 1-year follow-up of 103 patients aged 80 years or more.

103 patients with displaced femoral neck fractures (Garden 3-4) treated with primary hemiarthroplasty in the Department of Orthopedics, Malmö University Hospital, Sweden 1998-1999 were followed in a prospective, consecutive study for 1 year. Inclusion criteria were age of at least 80 years, signs of mental changes and/or residence in an institution. The control group consisted of 69 patients with internal fixation (Hansson hook pins). The arthroplasty group required more blood transfusions, a longer operation and had more superficial infections. No differences were detected as regards other complications, length of hospital stay, in-hospital mortality or ability to return home. The 1-year mortality rates were similar in the arthroplasty (29/103) and control groups (28/69). Within 1 year, we found a lower failure rate in the arthroplasty group (6/103) than in the control group (18/69). In the arthroplasty group, 2/103 had dislocations. Of the surviving arthroplasty patients at 12 months, 31/74 could walk as well as before the fracture and 55/74 had no pain. We recommend primary hemiarthroplasty for demented and/or institutionalized patients over 80 years with displaced femoral neck fractures.

Age Factors↗
PubMed2002

Additive effects of raloxifene and alendronate on bone density and biochemical markers of bone remodeling in postmenopausal women with osteoporosis.

Both raloxifene (RLX) and alendronate (ALN) can treat and prevent new vertebral fractures, increase bone mineral density (BMD), and decrease biochemical markers of bone turnover in postmenopausal women with osteoporosis. This phase 3, randomized, double-blind 1-yr study assessed the effects of combined RLX and ALN in 331 postmenopausal women with osteoporosis (femoral neck BMD T-score, less than -2). Women (aged < or = 75 yr; > or = 2 yr since their last menstrual period) received placebo, RLX 60 mg/d, ALN 10 mg/d, or RLX 60 mg/d and ALN 10 mg/d combined. At baseline, 6 and 12 months, BMD was measured by dual x-ray absorptiometry. The bone turnover markers serum osteocalcin, bone-specific alkaline phosphatase, and urinary N- and C-telopeptide corrected for creatinine were measured. The effects of RLX and ALN were considered to be independent and additive if the interaction effect was not statistically significant (P > 0.10) in a two-way ANOVA model. All changes in BMD and bone markers at 12 months were different between placebo and each of the active treatment groups, and between the RLX and RLX+ALN groups (P < 0.05). On average, lumbar spine BMD increased by 2.1, 4.3, and 5.3% from baseline with RLX, ALN, and RLX+ALN, respectively. The increase in femoral neck BMD in the RLX+ALN group (3.7%) was greater than the 2.7 and 1.7% increases in the ALN (P = 0.02) and RLX (P < 0.001) groups, respectively. The changes from baseline to 12 months in bone markers ranged from 7.1 to -16.0% with placebo, -23.8 to -46.5% with RLX, -42.3 to -74.2% with ALN, and -54.1 to -81.0% in the RLX+ALN group. RLX and ALN increased lumbar spine and femoral neck BMD, and decreased osteocalcin and C-telopeptide corrected for creatinine in an additive and independent manner, because the interaction effects were not significant. Although the ALN group had changes in BMD and bone markers that were approximately twice the magnitude as in the RLX group, it is not known how well these changes correlate to the clinical outcome of fracture. RLX+ALN reduced bone turnover more than either drug alone, resulting in greater BMD increment, but whether this difference reflects better fracture risk reduction was not assessed in this study.

Aged↗
PubMed2002

International variations in hip fracture probabilities: implications for risk assessment.

It is recommended that intervention thresholds should be based on absolute fracture risk, but there is a large variation in hip fracture incidence from different regions of the world. The aim of this study was to examine heterogeneity of hip fracture probability in different regions from recent estimates of hip fracture incidence and mortality to adjust intervention thresholds. Ten-year probabilities of hip fracture were computed in men and women at 10-year intervals from the age of 50 years and lifetime risks at the age of 50 years from the hazard functions of hip fracture and death. Lifetime risk at the age of 50 years varied from 1% in women from Turkey to 28.5% in women from Sweden. High lifetime risks in women were associated with high lifetime risks in men (r = 0.83). There also were significant correlations of 10-year risk at any age between men and women. Ten-year probability was standardized to that of men and women from Sweden (set at 1.0). There was a 15-fold range in 10-year probability from 1.24 in Norway to 0.08 in Chile. Countries were categorized by 10-year probabilities comprising very high risk (Norway, Iceland, Sweden, Denmark, and the United States), high risk (China [Taiwan [TW]], Germany, Switzerland, Finland, Greece, Canada, The Netherlands, Hungary, Singapore, Italy, United Kingdom, Kuwait, Australia, and Portugal), medium risk (China [Hong Kong [HK]], France, Japan, Spain, Argentina, and China), and low risk (Turkey, Korea, Venezuela, and Chile). The categorization of hip fracture probabilities can be used to adjust intervention thresholds based on age, sex, and relative risk from a reference population such as Sweden.

Aged↗
PubMedDate not supplied

Orthopaedic treatment of displaced femoral neck fractures in elderly patients.

PURPOSE AND METHOD: A review article concerning orthopaedic treatment and rehabilitation of displaced femoral neck fractures, focusing on evidence-based knowledge. RESULTS: Properly performed randomized controlled studies comparing internal fixation and primary arthroplasty provides the best basis to decide which method should be used. During the last decade, several such studies have been published, in addition to a few earlier works. After internal fixation with pins, screws or sliding hip screw and plate, the failure rate was 21 - 57% and re-operations were performed in 14 - 53% of all the cases. In the studies using THA, the failure rate was 4 - 11% and the re-operation rate 2 - 8%. The corresponding numbers for hemi-arthroplasty were 3 - 23% and 0 - 24%. A primary arthroplasty tends to result in better function and less pain during the rehabilitation period. CONCLUSION: With support in evidence-based literature, an elderly patient with displaced femoral neck fracture should be treated with a primary arthroplasty. If the individual is healthy, active and mentally intact, a total hip arthroplasty should be performed, otherwise a hemi-arthroplasty. This rationale ensures fewer failures and re-operations, as well as better function and less pain during the rehabilitation.

Arthroplasty, Replacement, Hip↗
PubMedDate not supplied

Recommendations for optimal care of the fragility fracture patient to reduce the risk of future fracture.

Fragility fractures resulting from low trauma events such as a fall from standing height affect up to one half of women and one third of men after age 50 years. These fractures are frequently associated with osteoporosis. History of a fragility fracture is among the strongest risk factors for future fracture. Therefore, optimal care of the patient with a fragility fracture includes not only treatment of the presenting fracture itself but also evaluation and treatment of the underlying cause or causes to prevent future fractures. However, despite the availability of therapeutic agents that reduce fracture risk among osteoporotic patients who have had a fracture, most patients with fragility fractures are not evaluated for osteoporosis or treated adequately to reduce the risk of future fracture. Orthopaedic surgeons are the first and often the only physicians seen by fracture patients. Thus, they have the unique opportunity to serve as primary advocates to ensure that appropriate action is taken to reduce the risk of future fracture.

Age Factors↗