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Lars Nordsletten

Publications and source records attributed to Lars Nordsletten.

13 recordsLinked to original sources
PubMed2006

Comparison of re-operation rates following primary and secondary hemiarthroplasty of the hip.

Primary arthroplasty or internal fixation are the most common ways of treating intracapsular femoral neck fractures, while arthroplasty is the preferred salvage treatment after failed internal fixation. A prospective registration of hip hemiarthroplasties between January 1998 and March 2002 identified 282 procedures for an acute femoral neck fracture and 149 procedures after failed internal fixation with two parallel screws. Chart review was performed after 19-74 months. The groups were comparable in co-morbidities and perioperative conditions. In the primary hemiarthroplasty group 15 of 282 (5%) arthroplasties were re-operated for complications compared to 16 of 149 (11%) in the secondary group (p=0.04). The most common re-operation was soft tissue debridement because of infection. There were more patients with an excision arthroplasty as end result in the secondary hemiarthroplasty group (6 (4%) versus 1 (0.4%); p=0.004). The higher risk of a re-operation after a salvage hemiarthroplasty should be considered when deciding between internal fixation and hemiarthroplasty as treatment for femoral neck fractures.

Aged↗
PubMed2006

Interprosthetic dislocations of the Charnley/Hastings hemiarthroplasty--report of 11 cases in 350 consecutive patients.

We report 11 cases of interprosthetic dislocation of the Charnley/Hastings hemiarthroplasty in a retrospective study of 350 consecutive patients treated for an acute femoral neck fracture. We found a total of 14 dislocations (4.0%), 11 were interprosthetic. The median age of the 350 patients was 79 (36-99) years and the median age of the 11 patients with an interprosthetic dislocation was 85 years (82-94). The median time from surgery to radiologically acknowledged dislocation was 18 (4-64) days. These interprosthetic dislocations may be caused by either an assembly mistake perioperatively, by maximum angulation and impingement between the components, or by trauma.

Adult↗
PubMed2006

The impact of body mass index on later total hip arthroplasty for primary osteoarthritis: a cohort study in 1.2 million persons.

OBJECTIVE: To investigate the effects of body mass index (BMI), height, and age on the risk of later total hip arthroplasty for primary osteoarthritis (OA). METHODS: We matched screening data on body height and weight from 1,152,006 persons ages 18-67 years who attended a compulsory screening for tuberculosis in 1963-1975 with data from the Norwegian Arthroplasty Register for the years 1987-2003. We identified 28,425 total hip replacements because of primary OA. RESULTS: We found dose-response associations between both height and BMI and later hip arthroplasty. The relative risk (RR) among men with a BMI > or = 32 kg/m2 versus a BMI of 20.5-21.9 kg/m2 was 3.4 (95% confidence interval [95% CI] 2.9-4.0). The corresponding RR in women was 2.3 (95% CI 2.1-2.4). There was a decreasing trend in the RR with an increasing age at screening. Among men, the RR for an increase of 5 kg/m2 in the BMI was 2.1 (95% CI 1.7-2.5) when measured at age <25 years and 1.5 (95% CI 1.3-1.7) when measured at ages 55-59 years. Among women, the corresponding RR values were 1.7 (95% CI 1.5-1.9) and 1.1 (95% CI 1.1-1.2). CONCLUSION: There was a strong dose-response association between BMI and later total arthroplasty for OA of the hip. Being overweight entailed the highest RR among young participants, and the participants who were overweight at a young age maintained an excess RR for arthroplasty throughout the followup period.

Adolescent↗
PubMed2006

Recombinant human bone morphogenetic protein-2 in open tibial fractures. A subgroup analysis of data combined from two prospective randomized studies.

BACKGROUND: The use of recombinant human bone morphogenetic protein-2 (rhBMP-2) to improve the healing of open tibial shaft fractures has been the focus of two prospective clinical studies. The objective of the current study was to perform a subgroup analysis of the combined data from these studies. METHODS: Two prospective, randomized clinical studies were conducted. A total of 510 patients with open tibial fractures were randomized to receive the control treatment (intramedullary nail fixation and routine soft-tissue management) or the control treatment and an absorbable collagen sponge impregnated with one of two concentrations of rhBMP-2. The rhBMP-2 implant was placed over the fracture at the time of definitive wound closure. For the purpose of this analysis, only the control treatment and the Food and Drug Administration-approved concentration of rhBMP-2 (1.50 mg/mL) were compared. Patients who anticipated receiving planned bone-grafting as part of a staged treatment were excluded from enrollment. RESULTS: Fifty-nine trauma centers in twelve countries participated, and patients were followed for twelve months postoperatively. Two subgroups were analyzed: (1) the 131 patients with a Gustilo-Anderson type-IIIA or IIIB open tibial fracture and (2) the 113 patients treated with reamed intramedullary nailing. The first subgroup demonstrated significant improvements in the rhBMP-2 group, with fewer bone-grafting procedures (p = 0.0005), fewer patients requiring invasive secondary interventions (p = 0.0065), and a lower rate of infection (p = 0.0234), compared with the control group. The second subgroup analysis of fractures treated with reamed intramedullary nailing demonstrated no significant difference between the control and the rhBMP-2 groups. CONCLUSIONS: The addition of rhBMP-2 to the treatment of type-III open tibial fractures can significantly reduce the frequency of bone-grafting procedures and other secondary interventions. This analysis establishes the clinical efficacy of rhBMP-2 combined with an absorbable collagen sponge implant for the treatment of these severe fractures.

Absorbable Implants↗
PubMed2005

Differences in stability and bone remodeling between a customized uncemented hydroxyapatite coated and a standard cemented femoral stem A randomized study with use of radiostereometry and bone densitometry.

The custom made Unique stem is designed to fit closely to the metaphyseal region of the femur in order to obtain maximum mechanical stability and optimal load transfer. Thirty-seven patients (38 hips) with non-inflammatory arthritis were randomized to the uncemented custom made Unique stem or the Elite Plus stem inserted with cement. The patients have been followed clinically as well as with radiostereometry (RSA) and Dual-energy X-ray Absorptiometry (DXA) for 2 years. After 2 years the RSA result showed minimal translation and rotation for the Unique stem while the Elite Plus rotated slightly (mean 1.05 degrees) into retroversion. Compared to previous studies the Elite Plus was as stable as the Charnley prosthesis. The DXA results showed a significantly higher proximal and total (10% for the Unique versus 5% for Elite) bone loss for the Unique stem compared to the Elite Plus. Thus the optimal proximal press-fit of the custom made stem did secure a stable fixation, but did not decrease the proximal bone loss.

Absorptiometry, Photon↗
PubMed2005

MRI diagnosis of occult hip fractures.

BACKGROUND: Most fractures of the proximal femur are easily diagnosed by conventional radiography. When the images are judged to be negative or equivocal and a clinical suspicion of fracture persists, another approach is to use magnetic resonance imaging (MRI) to help reach a diagnosis. METHODS: In a prospective study running from November 1998 to December 2001, we registered all patients being examined by MRI who had had a negative or equivocal radiograph and where there was continued clinical suspicion of hip fracture. RESULTS: 100 consecutive patients (67 women) were included, with an average age of 80 (37-100) years. The MRI examinations corresponded to 4% of the 2,350 patients admitted with hip trauma during the study period. 46 patients had a femoral neck or intertrochanteric fracture on MRI. 27 patients had other fractures. 18 had other findings on MRI, and 10 were interpreted as being negative, although one of these was a false negative. In a separate interobserver analysis, two experienced radiologists agreed on the diagnoses in 19/23 cases (kappa value 0.78). They agreed with a less experienced radiologist in 17/23 and 19/23 cases, respectively (kappa values 0.66 and 0.76). INTERPRETATION: MRI is a useful tool for demonstration of occult hip fractures. In the absence of a hip fracture, another explanation for the patient's pain and disability will often be given.

Adult↗
PubMed2004

Ultralok uncemented femoral prostheses: 12 to 15 year follow-up evaluation.

The results of total hip arthroplasty (THA) in young patients with osteoarthritis have been discouraging. In this prospective study, 78 patients (89 THA) were consecutively included and followed for 12 to 15 years (mean, 12.2 years) after the index surgery with the uncemented Ultralok femoral prosthesis (Zimmer, Wiltshire, UK). Age at surgery was 59.8 years (40 to 76). The follow-up process included an in-office clinical evaluation and a radiographic evaluation. A cumulative survival of 96.6% (with the end point defined as revision of the femoral component because of mechanical or radiographic loosening) was found for the femoral component after13 years, and all unrevised components were radiographically fixed by bony ingrowth. Twenty-three well-fixed stems had to be removed for femoral head damage at the time of the acetabular revision. The results of this comparatively large series show that good fixation has been achieved with a proximal titanium mesh and grit-blasted titanium alloy stem.

Aged↗
PubMed2004

Documentation of hip prostheses used in Norway: a critical review of the literature from 1996--2000.

We have conducted a systematic review of the scientific literature concerning outcome and clinical effectiveness of prostheses used for primary total hip replacement (THR) in Norway. The study is based on two Health Technology Assessment reports from the UK (Faulkner et al. 1998, Fitzpatrick et al. 1998), reviewing the literature from 1980 to 1995. Using a similar search strategy, we have evaluated the literature from 1996 through 2000. We included 129 scientific and medical publications which were assessed according to a specific appraisal protocol. The majority (72%) were observational studies, whereas only 9% were randomized studies. We could not retrieve any peer-reviewed documentation for one third of the implants. The Charnley prosthesis had by far the best and most comprehensive evidence base with better than 90% implant survival after about 10 years. Survival of the Charnley prosthesis declines by about 10% during each of the two following decades. Except for the Charnley and Lubinus IP, no other prosthesis on the market in Norway has given long-term results (> 15 years). 5 other cemented implants have given comparable results at about 10 years of follow-up. Some uncemented stems have shown promising medium-term outcome, but no combination of uncemented cup and stem fulfilled the benchmark criterion of > or = 90% implant survival at 10 years, which we propose as a minimum requirement for unrestricted clinical use for prostheses used in primary THR. New or undocumented implants should be introduced through a four-step model including preclinical testing, small series evaluated by radiosterometry, randomized clinical trial involving comparison with a well-documented prosthesis, and finally, surveillance of clinical use through registers.

Arthroplasty, Replacement, Hip↗
PubMed2004

Total hip arthroplasty with the Lord prosthesis. A long-term follow-up study.

BACKGROUND: The Lord prosthesis has been used rather extensively for total hip arthroplasty. In 1981, we began a prospective study for the purpose of determining the long-term results associated with the use of this prosthesis. In the present report, we describe the results for the living patients after a mean duration of follow-up of 17.5 years (range, fifteen to twenty years). METHODS: One hundred and two patients (116 hips) with a mean age of sixty-two years at the time of the index arthroplasty were included in the study. Eighty-nine hips were in women, and twenty-seven were in men. The Lord femoral prosthesis (with a 32-mm head) and the Lord threaded cup were used in all patients. The protocol included radiographic analysis, recording of complications, and a clinical evaluation. The patients were evaluated at one to four years, five to nine years, and fifteen to twenty years. RESULTS: One patient (one hip) refused to participate and forty-two patients (forty-five hips) died with the femoral component in place, leaving fifty-nine patients (seventy hips) available for clinical assessment. One femoral component was revised because of mechanical loosening, and one was revised because of a stem fracture. One stem appeared to be loose radiographically. Kaplan-Meier survivorship analysis with revision of the femoral component because of mechanical loosening, stem fracture, or radiographic loosening as the end point revealed a cumulative survival rate of 98% (95% confidence interval, 95.3% to 100.7%) (with twenty-eight hips at risk) at 17.5 years. Seventeen acetabular components were revised because of mechanical loosening, and sixteen were considered to be radiographically loose. Kaplan-Meier survivorship analysis with revision of the acetabular component because of mechanical or radiographic loosening as the end point revealed a cumulative survival rate of 65% (95% confidence interval, 53% to 72%) (with twenty-two hips at risk) at 17.5 years. CONCLUSIONS: We believe that the survival rate of the Lord femoral component after 17.5 years of follow-up was excellent. However, there was a substantial rate of proximal femoral bone loss. The results associated with the threaded cup were rather poor, and many patients had a loose implant but few symptoms. We recommend that patients with these implants be followed closely so that revision can be performed before substantial destruction of the acetabulum has occurred. LEVEL OF EVIDENCE: Therapeutic study, Level II-1 (prospective cohort study). See Instructions to Authors for a complete description of levels of evidence.

Adult↗
PubMed2003

Weight change and the risk of total hip replacement.

BACKGROUND: We examined the effect of adult weight change on risk for total hip replacement resulting from primary osteoarthritis, using a prospective study design. METHODS: We linked data on body mass index and body weight from 3 screening surveys in 3 Norwegian counties (mean ages at screenings 34, 43, and 47 y; n = 38,868) with follow-up data on total hip replacement (n = 572). Mean age at the start of follow up was 55 years, and mean duration of follow up was 9 years. For each participant we calculated a rate of weight change (weight slope) by linear regression of body weight versus time from the first through the third screening. RESULTS: Among men, mean weight change from first to last screening was +9.8 kg in the highest quartile and -3.7 kg in the lowest quartile. In women, the corresponding figures were +9.5 kg in the highest quartile and -5.2 kg in the lowest quartile. There was no association of weight slope, absolute weight change, or relative weight change between screenings with later total hip replacement resulting from primary osteoarthritis. We saw no change in the association between body mass index and later hip arthroplasty as the participants' age increased from 34 to 47 years at the 3 screenings. CONCLUSION: The risk for later total hip replacement resulting from primary osteoarthritis was unaffected by weight change during the fourth and fifth decades of life. The dose-response association between adult body mass index and later total hip replacement was similar across these age groups.

Adult↗
PubMed2002

Risk factors for total hip replacement due to primary osteoarthritis: a cohort study in 50,034 persons.

OBJECTIVE: To identify prospectively the possible risk factors for total hip replacement (THR) due to primary osteoarthritis in a large cohort. METHODS: Data from a cardiovascular screening were matched with 9 years of national data on THR. Mean age at the start of followup was 54.9 years, and the 50,034 participants were followed up for an average of 9 years. During followup, 672 persons had a first THR due to primary osteoarthritis. RESULTS: We found dose-response associations between body mass index (BMI), body weight, and the level of physical activity at work and THR for primary osteoarthritis. The highest versus the lowest quarter of BMI had a relative risk of 2.0 (95% confidence interval [95% CI] 1.4-2.9) among men and 3.0 (95% CI 2.1-4.1) among women. The highest versus the lowest quarter of body weight had a relative risk of 2.1 (95% CI 1.4-3.2) among men and 3.4 (95% CI 2.4-4.9) among women. Intensive versus sedentary physical activity at work had a relative risk of 2.1 (95% CI 1.5-3.0) among men and 2.1 (95% CI 1.3-3.3) among women. No association was found between physical activity in leisure and THR for primary osteoarthritis. CONCLUSION: Intensive physical activity at work and a high BMI each contribute significantly to the overall risk of undergoing THR due to primary osteoarthritis. Lowering the exposure to these risk factors may substantially reduce the need for hip replacement.

Adult↗
PubMedDate not supplied

Effects of alcohol on bone mineral and mechanical properties of bone in male rats.

The effect of ethanol on bone mineral is poorly understood. In this study we have investigated whether ethanol affects bone mineral content (BMC), bone mineral density (BMD) measured by dual energy X-ray absorptiometry, and the mechanical properties of the tibia and femora in male Sprague-Dawley rats without histopathological signs of liver disease or nutritional deficit. Thirty-five male rats were fed a liquid diet containing 15% ethanol and glucose. An equivalent iso-volumetric amount of glucose-containing liquid was fed to the controls (n = 35). After an initial difference in weight, we found no difference in weight gain from week 1 to week 6. All animals were killed at 6 weeks. We found no evidence of ethanol-induced liver disease in a histopathological evaluation. The BMD and BMC were found to be lower in the ethanol group. No differences between the groups were found in the mechanical properties or in the length and size of the femora. We suggest that alcohol may have a toxic effect on bone in male rats known not to suffer from any histopathological hepatic lesions.

Absorptiometry, Photon↗