SwePub
Sök i SwePub databas

  Utökad sökning

Träfflista för sökning "WFRF:(Toksvig Larsen Sören) "

Sökning: WFRF:(Toksvig Larsen Sören)

  • Resultat 1-50 av 53
Sortera/gruppera träfflistan
   
NumreringReferensOmslagsbildHitta
1.
  • Broberg, Karin, et al. (författare)
  • Trisomy 7 accumulates with age in solid tumors and non-neoplastic synovia
  • 2001
  • Ingår i: Genes, Chromosomes and Cancer. - 1045-2257. ; 30:3, s. 310-315
  • Tidskriftsartikel (refereegranskat)abstract
    • Trisomy 7 is a common finding in benign and malignant solid tumors, in several non-neoplastic lesions (for example, osteoarthritis and rheumatoid arthritis), and in apparently normal tissues as well, suggesting that the occurrence of +7 might be associated with factors other than the disease process itself. To find out whether the frequency of +7 varies with a patient's age, we cytogenetically analyzed short-term-cultured synovial samples from elderly persons without signs of arthritis and from young patients affected by juvenile chronic arthritis (JCA). In normal synovia, gain of a chromosome 7 was present as a clonal change in five of 10 cases and in single cells in four of the five remaining cases. In synovia from patients with JCA, cells with +7 were detected in only one of nine cases, representing the oldest patient in the series. Furthermore, we reviewed the cytogenetic literature on tumors of the brain, breast, colon, kidney, lung, skin, thyroid, and upper aerodigestive tract. In the majority (six of eight) of these tumor types, the frequency of cases displaying a clone with +7 as the sole aberration increased with age. Taken together, the results presented here suggest that the acquisition of trisomy 7 in some neoplastic and non-neoplastic tissues might be associated with age rather than with disease. The finding of a completely different frequency distribution in two of the tumor types (tumors of the brain and the thyroid gland), however, emphasizes the heterogeneity of +7 and indicates that other, possibly tissue-specific, factors might influence the occurrence of this mutation.
  •  
2.
  • Broberg Palmgren, Karin, et al. (författare)
  • The tumor-associated gene HMGIC is expressed in normal and osteoarthritis-affected synovia
  • 2001
  • Ingår i: Modern Pathology. - : Elsevier BV. - 1530-0285 .- 0893-3952. ; 14:4, s. 311-317
  • Tidskriftsartikel (refereegranskat)abstract
    • Chromosomal rearrangements involving chromosome bands 12q13-15 are very frequent findings in benign solid tumors, and recently, the primary molecular target for these aberrations was identified as the gene HMGIC. However, mutations in this gene have also been observed in nonneoplastic tissues. In a previous study, we reported breakpoints within HMGIC of synovia affected by osteoarthritis (OA) in two cases with 12q15 aberrations. To analyze further the role of HMGIC in this disease, we have performed cytogenetic, fluorescent in situ hybridization (FISH), RNA, and protein expression analyses on synovial samples from patients with OA and individuals without signs of the disorder. Cytogenetic analysis of short-term cultured cells revealed clonal 12q13-15 aberrations in 2/36 cases of OA synovia and no rearrangement in any of the five controls. With FISH analysis, it was shown that the chromosomal breakpoints in the two aberrant cases were located outside the HMGIC locus. In contrast, at RNA and protein expression analyses, OA-affected as well as normal synovia displayed transcription and translation of the gene. We also analyzed whether immunoreactivity for HMGIC was associated with the proliferation-specific antigen Ki-67, but no correlation between the staining patterns of these proteins was observed. From the results of the present study, it is evident that expression of HMGIC cannot simply be considered a sign of neoplasia or an effect of proliferation.
  •  
3.
  •  
4.
  • Catani, F, et al. (författare)
  • The stability of the cemented tibial component of total knee arthroplasty
  • 2004
  • Ingår i: Journal of Arthroplasty. - : Elsevier BV. - 0883-5403. ; 19:6, s. 775-782
  • Tidskriftsartikel (refereegranskat)abstract
    • Micromotion of the tibial component in 40 knee arthroplasties for gonarthrosis was studied rising Roentgen stereophotogrammetric analysis. The stability of this component was assessed for 2 years' postoperatively. in all arthroplasties, an attempt was made to reconstruct the preoperative posterior slope. Posterior cruciate-retaining (CR) and posterior-stabilized (PS) components showed at 2 years a maximum total point motion of 0.6 +/- 0.4 mm and 0.7 +/- 0.5 mm, respectively. Whereas 92.5% of the implants were determined to be stable, 1 of the CR group and 2 of the PS group displayed migration between the first and the second year of at least 0.2 mm. A negative correlation between subsidence of the tibial component at 2 years of follow-up and the difference between preoperative and postoperative tibial slope was found. Consequently, we suggest that restoring the original posterior slope of the tibial plateau must be a goal of tibial component implantation.
  •  
5.
  • Gustafsson, Johan, et al. (författare)
  • MRI of the knee after locked unreamed intramedullary nailing of tibia.
  • 2008
  • Ingår i: La Chirurgia degli organi di movimento. - : Springer Science and Business Media LLC. - 0009-4749 .- 1973-2538. ; 91:1, s. 45-50
  • Tidskriftsartikel (refereegranskat)abstract
    • We analysed the reason for knee pain after intramedullary (IM) nailing with standard MRI sequences at a mean of 27 months (range 2-45) after nail removal in eleven patients with a mean age of 30 years (range 15-52). Knee pain was assessed in four grades. All our patients had signal changes of fluid in the nail channel, areas of low signal intensity in Hoffa's fat pad and subcutaneous low signal nodes in front of a thickened patellar ligament. Ten patients had low signal adhesions from the nail insertion towards the patellar ligament. Six patients had severe knee pain and even marked adhesions. Two patients had no knee pain; one of these two had minimal adhesions and the other one no adhesions. Five of the patients had a meniscal tear and/or local cartilage reduction. The degree of adhesions from the nail insertion in the tibia towards the patellar ligament was proportional to the degree of knee pain. No sign of acute inflammation was found.
  •  
6.
  • Hansson, Ulrik, et al. (författare)
  • A randomised RSA study of Peri-apatite((TM)) HA coating of a knee prosthesis
  • 2004
  • Ingår i: Key Engineering Materials. - 1013-9826. ; 254-2, s. 623-625
  • Tidskriftsartikel (refereegranskat)abstract
    • Fifty knees scheduled for a total knee prosthesis were randomized in two groups. Both groups had a noncemented fixation of the porous-coated implants but one group received a prosthesis with ceramic coating on the porous surface of the implant. The knees were evaluated with RSA technique regarding micromotion the first two years. There were less micromotion in the coated group. The results indicate that the technique for ceramic coating here studied provides a safe and stable fixation of the implants.
  •  
7.
  • Hansson, Ulrik, et al. (författare)
  • A randomised RSA study of Peri-Apatitetrade mark HA coating of a total knee prosthesis.
  • 2008
  • Ingår i: Knee. - : Elsevier BV. - 1873-5800. ; 15, s. 211-216
  • Tidskriftsartikel (refereegranskat)abstract
    • BACKGROUND: In total knee replacement, sound early fixation of the prosthesis is crucial for achieving a good long-term result and for minimising the risk of loosening. Various types of prosthetic material, different surface textures and shapes and the incorporation of screws or pegs have been used to achieve good fixation, particularly in the uncemented knee. Hydroxyapatite (HA) coating of prosthetic joint components is another technique used to enhance early stability and so to improve the longevity of the prosthesis-bone fixation. HA ceramic coatings are mostly plasma sprayed onto the fixation surface of the implant. Plasma spraying is largely a 'line of sight' technique and as such there are difficulties involved when covering three-dimensional planes, such as porous beaded fixation surfaces typically found on several knee prostheses. The objective of this study was to assess the clinical performance of the solution-deposited HA coating, Peri-Apatitetrade mark , with regard to its ability to stimulate an endurable and stable implant fixation. PATIENTS AND METHODS: We randomised 60 patients into two groups; one group received the porous coated prosthesis with solution-deposited HA, and the other group received a prosthesis without HA. Radiostereometric examination was used as the primary tool for measuring migration in the prosthetic components. RESULTS: There was a lower incidence of early subsidence in the Peri-Apatitetrade mark group. At 24 months there were no differences in clinical scorings or maximal total point motion. CONCLUSION: Addition of solution-deposited HA coating appears to provide better early stable fixation in a porous coated knee prosthesis.
  •  
8.
  • Hansson, Ulrik, et al. (författare)
  • Mobile vs. fixed meniscal bearing in total knee replacement A randomised radiostereometric study.
  • 2005
  • Ingår i: Knee. - : Elsevier BV. - 1873-5800. ; 12:6, s. 414-418
  • Tidskriftsartikel (refereegranskat)abstract
    • 52 knees scheduled for a total knee arthroplasty were randomised to either a fixed or a mobile polyethylene bearing. The design was identical in all parts. The knee systems used were the Rotaglide Total Knee System (RTK) (R) and the Nuffield Total Knee System (NTK) (R), both from the same manufacturer (Corin Medical Ltd., UK). All knees implanted were uncemented. The patients were followed for 2 years clinically and with radiostereometric analyses to assess migration over time and inducible displacement of the tibial component. Separate analysis of the mobility of the tibial insert in the knees with a mobile bearing was also made. The migration measured with RSA between the I st and 2nd year expressed as maximum total point motion (MTPM) might predict the risk of loosening of the implant.
  •  
9.
  • Hansson, Ulrik, et al. (författare)
  • Once-weekly oral medication with alendronate does not prevent migration of knee prostheses : A double-blind randomized RSA study
  • 2009
  • Ingår i: Acta Orthopaedica. - : Informa Healthcare. - 1745-3674 .- 1745-3682. ; 80:1, s. 41-45
  • Tidskriftsartikel (refereegranskat)abstract
    • Background and purposeEarly migration of joint replacements is an effect of poor fixation and can predict late loosening. By reducing the bone resorption after implantation of a joint replacement, it should be possible to enhance the initial fixation of the implant. We studied the effect of once-weekly treatment with alendronate after knee replacement.Patients and methodsWe recruited 60 patients (60 knees) with gonarthrosis who were scheduled for a total knee replacement. They were operated on with identical implants and uncemented fixation. 30 patients were treated with a bisphosphonate (alendronate) and 30 patients underwent placebo treatment. The treatment started postoperatively and continued on a weekly basis for 6 months. The fixation of the implants was measured with repeated radiostereometry for 2 years.ResultsThere was no difference in migration of implants between the two groups.ConclusionWith uncemented fixation of knee implants, no benefit of once-weekly treatment with alendronate, starting postoperatively, could be seen during a 2-year follow-up period.
  •  
10.
  • Hansson, Ulrik, et al. (författare)
  • Once-weekly oral medication with alendronate does not prevent migration of knee prostheses
  • 2009
  • Ingår i: Acta Orthopaedica. - : Medical Journals Sweden AB. - 1745-3682 .- 1745-3674. ; 80:1, s. 41-45
  • Tidskriftsartikel (refereegranskat)abstract
    • Background and purpose Early migration of joint replacements is an effect of poor fixation and can predict late loosening. By reducing the bone resorption after implantation of a joint replacement, it should be possible to enhance the initial fixation of the implant. We studied the effect of once-weekly treatment with alendronate after knee replacement. Patients and methods We recruited 60 patients (60 knees) with gonarthrosis who were scheduled for a total knee replacement. They were operated on with identical implants and uncemented fixation. 30 patients were treated with a bisphosphonate (alendronate) and 30 patients underwent placebo treatment. The treatment started postoperatively and continued on a weekly basis for 6 months. The fixation of the implants was measured with repeated radiostereometry for 2 years. Results There was no difference in migration of implants between the two groups. Conclusion With uncemented fixation of knee implants, no benefit of once-weekly treatment with alendronate, starting postoperatively, could be seen during a 2-year follow-up period.
  •  
11.
  • Harding, Anna Kajsa, et al. (författare)
  • A single bisphosphonate infusion does not accelerate fracture healing in high tibial osteotomies.
  • 2011
  • Ingår i: Acta orthopaedica. - : Medical Journals Sweden AB. - 1745-3682 .- 1745-3674.
  • Tidskriftsartikel (refereegranskat)abstract
    • Background Bisphosphonates increase the callus size and strength in animal fracture studies. In a human non-randomized pilot study of high tibial osteotomies in knee osteoarthritis, using the hemicallotasis (HCO) technique, bisphosphonates shortened the healing time by 12 days. In the present randomized study, we wanted to determine whether a single infusion of zoledronic acid reduces the time to clinical osteotomy healing. Results from the same trial, showing improved pin fixation with zoledronate, have been published separately. Methods 46 consecutive patients (aged 35-65 years) were operated. At 4 weeks postoperatively, the patients were randomized to an intravenous infusion of either zoledronic acid or sodium chloride. Dual-energy X-ray absorptiometry (DEXA) was performed 10 weeks postoperatively. Radiographs were taken at 10 weeks and every second week until there was radiographic and clinical healing. Healing was evaluated blind, with extraction of the external fixator as the endpoint. At 1.5 years, an additional radiograph was taken and the hip-knee-ankle (HKA) angle measured to evaluate whether correction had been retained. Results All osteotomies healed with no difference in healing time between the groups (77 (SD 7) days). Bone mineral density and bone mineral content, as assessed with DEXA, were similar between the groups. Radiographically, both groups had retained the acquired correction at the 1.5-year follow-up. Interpretation In this randomized comparison, a single infusion of zoledronic acid increased the pin fixation of the external frame but did not shorten the healing time. In both groups, the external fixator was extracted almost 2 weeks earlier than in previous studies. The early extraction did not cause a loss of correction in either group.
  •  
12.
  • Harding, Anna Kajsa, et al. (författare)
  • A single dose zoledronic acid enhances pin fixation in high tibial osteotomy using the hemicallotasis technique. A double-blind placebo controlled randomized study in 46 patients.
  • 2010
  • Ingår i: Bone. - : Elsevier BV. - 1873-2763 .- 8756-3282. ; 46:3, s. 649-654
  • Tidskriftsartikel (refereegranskat)abstract
    • INTRODUCTION: Bisphosphonates have been shown to reduce osteoclastic activity and enhance pin fixation in both experimental and clinical studies. In this prospective, randomized study of high tibial osteotomy using the hemicallotasis (HCO) technique, we evaluate whether treatment by one single infusion of zoledronic acid can enhance the pin fixation. MATERIALS AND METHODS: 46 consecutive patients (35-65 years) were operated on for knee osteoarthritis by the HCO technique. After the osteotomy, two hydroxyapatite-coated pins were inserted in the metaphyseal bone and two non-coated pins in the diaphyseal bone. The insertion torque was measured by a torque force screw driver. Four weeks postoperatively, the patients were randomized to either one infusion of zoledronic acid or sodium chloride intravenously. At time for removal of the pins, the extraction torque forces of the pins were measured. RESULTS: All osteotomies healed and no difference was found in time to healing. The mean extraction torque force in the non-coated pins in the diaphyseal bone was doubled in the zoledronic treated group (4.5 Nm, SD 2.1) compared to the placebo group (2.4 (SD 1.0, p<0.0001). The mean extraction torque forces of the hydroxyapatite-coated pins in the metaphyseal bone were similar in the zoledronic acid group (4.7 Nm, SD 1.3) and in the placebo group (4.0 Nm, SD 1.3). DISCUSSION: A single infusion of zoledronic acid improved twofold the fixation of non-coated pins in diaphyseal bone. Bisphosphonates might be an alternative to hydroxyapatite-coated pins in nonosteoporotic bone.
  •  
13.
  • Harsten, Andreas, et al. (författare)
  • Recovery after total intravenous general anaesthesia or spinal anaesthesia for total knee arthroplasty: a randomized trial.
  • 2013
  • Ingår i: British Journal of Anaesthesia. - : Elsevier BV. - 1471-6771 .- 0007-0912. ; 111:3, s. 391-399
  • Tidskriftsartikel (refereegranskat)abstract
    • BACKGROUND: /st>This study was undertaken to compare the effects of general anaesthesia (GA) and spinal anaesthesia (SA) on the need for postoperative hospitalization and early postoperative comfort in patients undergoing fast-track total knee arthroplasty (TKA). METHODS: /st>One hundred and twenty subjects were randomly allocated to receive either intrathecal bupivacaine (SA group) or GA with target controlled infusion of propofol and remifentanil (GA group). Primary outcome was length of hospital stay (LOS) defined as time from end of surgery until the subject met the hospital discharge criteria. Secondary outcome parameters included actual time of discharge, postoperative pain, intraoperative blood loss, length of stay in the Post Anaesthesia Care Unit, dizziness, postoperative nausea and vomiting, need for urinary catheterization and subject satisfaction. RESULTS: /st>GA resulted in shorter LOS (46 vs 52 h, P<0.001), and less nausea and vomiting (4 vs 15, P<0.05) and dizziness (VAS 0 mm vs 20 mm, P<0.05) compared with SA. During the first 2 postoperative hours, GA patients had higher pain scores (P<0.001), but after 6 h the SA group had significantly higher pain scores (P<0.001). Subjects in the GA group used fewer patient-controlled analgesia doses and less morphine (P<0.01), and were able to walk earlier compared with the SA group (P<0.001). Subjects receiving SA would request a change in the method of anaesthesia in the event of a subsequent operation more often than the GA subjects (P<0.05). CONCLUSION: /st>GA had more favourable recovery effects after TKA compared with SA.
  •  
14.
  • Harsten, Andreas, et al. (författare)
  • Total hip arthroplasty and perioperative oral carbohydrate treatment: a randomised, double-blind, controlled trial.
  • 2012
  • Ingår i: European Journal of Anaesthesiology. - 1365-2346. ; 29:6, s. 271-274
  • Tidskriftsartikel (refereegranskat)abstract
    • CONTEXT: Perioperative oral carbohydrate intake is beneficial to general surgery patients. Total hip arthroplasty is a common surgical procedure, and even a moderate improvement in patient outcome could have a significant effect on the resources needed for these patients. However, few studies have focused on the effects of carbohydrate intake on orthopaedic patients. OBJECTIVE: The purpose of this study was to investigate if perioperative oral carbohydrate intake alters the postoperative course for patients undergoing total hip arthroplasty. The primary hypothesis was that pain scores would be lower in patients treated with carbohydrate. DESIGN: A randomised, double-blind, controlled trial. SETTING: This study was carried out between September 2009 and April 2011 at a district Swedish hospital that specialises in orthopaedic surgery. PATIENTS: Sixty ASA physical status I-III patients scheduled for elective total hip arthroplasty were included. Exclusion criteria were obesity, diabetes, prior hip surgery to the same hip, ongoing infection, immunological deficiency or age less than 50 or more than 80 years. INTERVENTIONS: Patients were given 400 ml of either an oral 12.5% carbohydrate solution or a placebo beverage (flavoured water) 1.5 h before and 2 h after surgery. MAIN OUTCOME MEASURES: Visual analogue scales were used to score six discomfort parameters. RESULTS: Immediately prior to surgery, the carbohydrate-treated patients were less hungry (median score 9.5 vs. 22 mm) and experienced less nausea (0 vs. 1.5 mm) (P < 0.05). Postoperatively, patients in the carbohydrate group experienced less pain at 12, 16 and 20 h (median scores 20, 30 and 34 vs. 7, 5 and 0 mm; P < 0.05). CONCLUSION: This study shows that there is limited benefit from administering oral carbohydatre prior to total hip arthroplasty.
  •  
15.
  •  
16.
  •  
17.
  • Hasan, Shaho, et al. (författare)
  • All-polyethylene versus metal-backed posterior stabilized total knee arthroplasty : similar 2-year results of a randomized radiostereometric analysis study
  • 2019
  • Ingår i: Acta Orthopaedica. - : Medical Journals Sweden AB. - 1745-3674 .- 1745-3682. ; 90:6, s. 590-595
  • Tidskriftsartikel (refereegranskat)abstract
    • Background and purpose — The all-polyethylene tibial (APT) component, introduced in the early 1970s, was surpassed by metal-backed tibial (MBT) trays as the first choice for total knee arthroplasty (TKA). With improved polyethylene, the modern APT components can reduce costs, and have shown equivalent results in survivorship and early migration of the cruciate-retaining and cruciate-stabilizing designs. This study compares the 2-year migration of a similarly designed APT-posterior stabilized (PS) and a MBT-PS TKA, using radiostereometric analysis (RSA). Patients and methods — 60 patients were randomized to receive either an APT Triathlon PS or an MBT Triathlon PS TKA (Stryker, NJ, USA). Migration measured by RSA and clinical scores were evaluated at baseline and at 3, 12, and 24 months postoperatively. Repeated measurements were analyzed with a linear mixed model and generalized estimating equations. Results — The mean maximum total point movement (MTPM) at 3, 12, and 24 months was 0.41 mm (95% CI 0.33–0.50), 0.57 mm (0.44–0.70), and 0.56 mm (0.42–0.69) respectively in the MBT group and 0.46 mm (0.36–0.57), 0.61 mm (0.49–0.73), and 0.64 mm (0.50–0.77) in the APT group. 2 MBT and 1 APT implant were considered unstable at the 2-year follow-up. The KSS Knee score and KSS Function across 3, 12, and 24 months were comparable in both groups. Interpretation — For an APT-PS designed component, MTPM measured with RSA is comparable to the MBT-PS component after 2 years of follow-up. No differences in complications or clinical outcomes were found.
  •  
18.
  • Hasan, Shaho, et al. (författare)
  • Late stabilization after initial migration in patients undergoing cemented total knee arthroplasty : a 5-year followup of 2 randomized controlled trials using radiostereometric analysis
  • 2022
  • Ingår i: Acta Orthopaedica. - : Medical Journals Sweden AB. - 1745-3682 .- 1745-3674. ; 93, s. 271-276
  • Tidskriftsartikel (refereegranskat)abstract
    • BACKGROUND AND PURPOSE: In total knee arthroplasty (TKA), metal-backed (MBT) and all-polyethylene (APT) designs have shown comparable implant migration up to 2 years postoperatively using radiostereometric analysis (RSA). However, studies comparing mid-term migration of both designs are lacking. Furthermore, continuously migrating TKAs up to 2 years may continue to migrate or stabilize thereafter. Therefore, we compared 5-year migration of MBT and APT using either cruciate-stabilizing (CS) or posteriorstabilizing (PS) designs and specifically assessed migration profiles of continuously migrating TKAs beyond 2 years. PATIENTS AND METHODS: The present study includes results from 2 randomized trials comparing migration of cemented MBT with APT of either CS (CS study, n = 59) or PS (PS study, n = 56) design. 2 surgeons performed all surgeries. We used a linear mixed model for the analyses. RESULTS: The overall migration between MBT and APT TKAs was similar for either the CS or PS design over a 5-year period. In both studies combined, 9 implants showed continuous migration in the second postoperative year, of which 1 (APT-CS) was revised for instability, 4 (2 MBT-CS, MBT-PS, APT-PS) stabilized, and 4 (2 MBT-CS, APT-CS, MBT-PS) lacked 5-year data. INTERPRETATION: Overall migration was similar between MBT and APT TKAs up to 5 years, for both the CS and PS design. 4 initially migrating TKAs stabilized between 2- and 5-year follow-up, stressing the need for longer-term followup to determine whether second-year continuous migration correctly predicts loosening.
  •  
19.
  • Hasan, Shaho, et al. (författare)
  • The Influence of Postoperative Coronal Alignment on Tibial Migration After Total Knee Arthroplasty in Preoperative Varus and Valgus Knees : A Secondary Analysis of 10 Randomized Controlled Trials Using Radiostereometric Analysis
  • 2021
  • Ingår i: The Journal of bone and joint surgery. American volume. - 1535-1386. ; 103:24, s. 2281-2290
  • Tidskriftsartikel (refereegranskat)abstract
    • BACKGROUND: Orthopaedic surgeons aim for mechanical alignment when performing total knee arthroplasty (TKA) as malalignment is associated with loosening. Loosening may be predicted by migration as measured with radiostereometric analysis (RSA), but previous RSA studies on postoperative alignment have shown contradictory results and have been limited to cemented implants and small numbers of patients. Therefore, we performed a secondary analysis of 10 previously published randomized controlled trials (RCTs) to compare migration between postoperative in-range and out-of-range cemented and uncemented TKA implants among patients with a preoperative varus or valgus knee. METHODS: All RCTs involving the use of RSA that had been conducted at 2 centers were included. Alignment was classified, with use of the hip-knee-ankle angle (HKA), as in-range (0° ± 3°) or out-of-range (<-3° or >3°). The fixation methods included cemented, uncemented-coated, and uncemented-uncoated. Migration was measured at 3, 12, and 24 months. A linear mixed model was used, with adjustment for fixation method and clustering of patients within centers. RESULTS: Of 476 TKA implants that had been out-of-range preoperatively, 290 were in-range postoperatively and 186 were out-of-range in either varus (n = 143) or valgus (n = 43) postoperatively. The mean migration at 3, 12, and 24 months was 0.73 mm (95% confidence interval [CI], 0.66 to 0.79 mm), 0.92 mm (95% CI, 0.85 to 1.00 mm), and 0.97 mm (95% CI, 0.90 to 1.05 mm), respectively, for the in-range group and 0.80 mm (95% CI, 0.72 to 0.87 mm), 0.98 (95% CI, 0.90 to 1.07 mm), and 1.04 mm (95% CI, 0.95 to 1.13 mm), respectively, for the out-of-range group (p = 0.07). The fixation method significantly influenced migration, with uncemented-uncoated implants migrating more than cemented and uncemented-coated implants (p < 0.001). CONCLUSIONS: Postoperative alignment did not influence migration of TKAs in the first 2 postoperative years in patients with preoperative varus or valgus alignment of the knee. However, the fixation method significantly influenced migration, with uncemented-uncoated implants showing the greatest migration. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.
  •  
20.
  • Henricson, Anders, 1944- (författare)
  • Total knee arthroplasty : aspects on improved fixation in the younger patient
  • 2008
  • Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
    • The results of total knee arthroplasty are inferior in younger patients. The challenge today is therefore to develop designs and concepts that will last at least 25 years. This thesis has evaluated the fixation to bone of modern designs of knee prostheses uring RSA analysis. Coating implant surfaces with hydroxy-apatite have proven to enhance fixation to bone. Addition of screws for fixation of the tibial component enhances the fixation, but has negative side effects such as osteolysis around the screws, in turn leading to a higher risk of component loosening. The magnitude and pattern of migration was studied in a randomized study of uncemented tibial implants coated with hydroxy-apatite with and without additional screw fixation in patients younger than 65 years. The uncemented implants migrated initially more than the cemented implants that constituted the control group. Both uncemented groups stabilized at 3 monthes with no further migration, while the cemented implants showed a continuous migration up to the 2 year follow-up, indicating continuous bone resorption at the implant-bone interface, a fact that might lead to an increased risk of late implant loosening. This may not be a problem in older patients, but may have consequences for long-term fixation in younger patients. There was no difference between the two uncemented groups indicating that screws do not improve fixation. Hydroxy-apatite coated knee implants might be well suited for younger patients. Mobile bearing total knee arthroplasty theoretically uncouples the forces at the implant-bone interface, thus improving fixation of the implant to bone. The magnitude and pattern of migration of a cemented mobile bearing knee arthroplasty and a fixed bearing total knee arthroplasty was compared in a randomized study. The results showed that mobile bearings did not improve fixation. Trabecular metal, a new material recently introduced for total knee arthroplasty, has several theoretical advantages. Trabecular metal tibial implants were evaluated in a randomized study in patients younger than 60 years. The implants displayed the typical migration pattern for uncemented implants with greater migration initially followed by early stabilization. The majority of the trabecular metal implants subsided into the bone with no lift-off. Lift-off has the potential of exposing the interface to joint fluid with the potential risk of bone resorption and late loosening, and is commonly seen in metal-backed implants. The finding of absence of lift-off is regarded beneficial for uncemented fixation. Trabecular metal tibial implants might be suited for younger patients. The optimal mode of fixation of the femoral component is yet to be established. Comparing cemented femoral components with uncemented femoral components in a randomized study in patients younger than 60 years revealed no differences of the magnitude or the pattern of migration. Uncemented femoral component seems equally as good as cemented components in younger patients.
  •  
21.
  • Hjartarson, Hjörtur F., et al. (författare)
  • The clinical effect of an unloader brace on patients with osteoarthritis of the knee, a randomized placebo controlled trial with one year follow up
  • 2018
  • Ingår i: BMC Musculoskeletal Disorders. - : Springer Science and Business Media LLC. - 1471-2474. ; 19:1
  • Tidskriftsartikel (refereegranskat)abstract
    • Background: Treatment of patients with knee osteoarthritis is challenging. Unloader braces have been developed with various success. Unloader One® Knee Brace is light, easily-fitted and shown to be effective by the unloading of the affected compartment. The aim of the study was to assess the clinical outcome of the brace vs. a placebo on patients with knee osteoarthritis. Methods: Initially 150 patients were randomized to receive either the Unloader brace or a control placebo group look-alike brace where the active strips had been removed. The patients were followed up at 6,12,26 and 52 weeks with Knee Society Score (KSS) and Knee injury and Osteoarthritis Outcome Score (KOOS). The reason for dropout was recorded. Results: A total of 149 patients were included, 74 in the study and 75 in the control group. The mean age was 59.6 vs. 60.2, BMI was 27.5 vs. 26.9, 37% vs. 44% were women in the study vs. control group. Both groups showed improvement in KSS over 52 weeks, with the study group showing higher improvement in mean scores. KSS increased from 64.3 to 84.0 for the study group and from 64.0 to 74.6 for the control group (p = 0.009). The study group improved in KSS function from 67.0 to 78.6 (p < 0.001) and KOOS for knee related symptoms increased/improved from 64.3 to 72.4 (p < 0.001). Activity of daily living increased/improved from 65.3 to 75.2 and Sports/Recreation from 24.6 to 40.2 (p > 0.001) whereas the control group did not show significant improvements in any of the scores. The dropout was higher in the control group, 40 vs. 25. Conclusions: The brace seems to be more effective and better tolerated than the placebo. Trial registration: The trial was retrospectively registered with ClinicalTrials.gov (NCT03454776) on March 6th 2018.
  •  
22.
  •  
23.
  • Lindstrand, Anders, et al. (författare)
  • The patella in total knee arthroplasty: resurfacing or nonresurfacing of patella
  • 2001
  • Ingår i: Knee Surgery, Sports Traumatology, Arthroscopy. - : Springer Science and Business Media LLC. - 1433-7347 .- 0942-2056. ; 9:Suppl 1, s. 21-23
  • Tidskriftsartikel (refereegranskat)abstract
    • Data from the Swedish Knee Arthroplasty Registry were analyzed to compare bi- and tricompartmental knee arthroplasties carried out in patients operated on for arthrosis in 1990-1996. Of the 16,607 primary arthroplasties that were carried out there were 5,139 with patellar replacement in the primary procedure and 10,928 without. By April 1998, 280 revisions were performed, 250 of these cases were analyzed in this study. Patella-related complications were commonly the reason for early revision: in 99 of the 168 knees with a primary bicompartmental procedure and in 36 of the 82 knees with a primary tricompartmental procedure. This presentation merely analyzes the extent of patellar problems in knee arthroplasty, as a detailed analysis of the causes of this common problem is not possible using data from a national multicenter study.
  •  
24.
  • Lohmander, Stefan, et al. (författare)
  • Surgical treatment of osteoarthritis
  • 2006
  • Ingår i: Osteoarthritis Handbook. - 9781841842851 - 1841842850 ; , s. 161-161
  • Bokkapitel (övrigt vetenskapligt/konstnärligt)
  •  
25.
  • Molt, Mats, et al. (författare)
  • 2-year follow-up report on micromotion of a short tibia stem.
  • 2015
  • Ingår i: Acta Orthopaedica. - : Medical Journals Sweden AB. - 1745-3682 .- 1745-3674. ; 86:5, s. 594-598
  • Tidskriftsartikel (refereegranskat)abstract
    • Background and purpose - A shortened tibial stem could influence the early prosthetic fixation. We therefore compared the short stem to the standard-length stem using radiostereometric analysis (RSA) as primary outcome measure. Patients and methods - 60 patients were randomized to receive a cemented Triathlon total knee arthroplasty (TKA) with a tibial tray of either standard or short stem length. The patients were blinded regarding treatment allocation. The micromotion of the tibial component was measured by RSA postoperatively, at 3 months, and after 1 and 2 years; clinical outcome was measured with the American Knee Society score (AKSS) and the knee osteoarthritis and injury outcome score (KOOS). Results - The maximum total point motion (MTPM) for the standard stem was 0.36 (SD 0.16) mm at 3 months, 0.51 (SD 0.27) mm at 1 year, and 0.54 (SD 0.28) mm at 2 years. For the short stem, it was 0.42 (0.24) mm, 0.59 (0.43) mm, and 0.61 (0.39) mm. 4 short-stemmed components and 2 standard-stemmed components had more than 0.2 mm of migration between the first- and second-year follow-up, and were classified as continuously migrating. Interpretation - The short-stemmed cemented tibial prosthesis showed an early prosthetic migratory pattern similar to that of the standard-stemmed cemented Triathlon knee prosthesis. The number of continuously migrating tibial plates in each group is predictive of a lower revision rate than 5% at 10 years.
  •  
26.
  • Molt, Mats, et al. (författare)
  • A randomized RSA study concentrating especially on continuous migration : A randomized RSA study concentrating especially on continuous migration
  • 2016
  • Ingår i: Acta Orthopaedica. - : Informa UK Limited. - 1745-3674 .- 1745-3682. ; 87:3, s. 262-267
  • Tidskriftsartikel (refereegranskat)abstract
    • Background and purpose — There is a general call for phased introduction of new implants, and one step in the introduction is an early evaluation of micromotion. We compared the micromotion in the Triathlon and its predecessor, the Duracon total knee prosthesis, concentrating especially on continuous migration over 5 years of follow-up. Patients and methods — 60 patients were randomized to receive either a cemented Triathlon total knee prosthesis or a cemented Duracon total knee prosthesis. 3-D tibial component migration was measured by radiostereometric analysis (RSA) at 3 months and at 1, 2, and 5 years. Results — There was no statistically significant difference in maximum total point motion (MTPM) between the 2 groups (p = 0.1). The mean MTPM at 5 years for the Duracon was 1.10 (SD 1.21) mm and for the Triathlon it was 0.66 (SD 0.38) mm. The numbers of continuously migrating prostheses were similar in the groups at the fifth year of follow-up; 6 of 21 prostheses in the Duracon group and 3 of 21 in the Triathlon group had migrated more than 0.3 mm between the second year and the fifth year of follow-up (p = 0.2). Interpretation — The Triathlon has a micromotion pattern similar to that of the Duracon total knee system at both short-term and medium-term follow-up, and may therefore, over time, show the same good long-term mechanical stability.
  •  
27.
  •  
28.
  • Molt, Mats, et al. (författare)
  • The effect of tourniquet use on fixation quality in cemented total knee arthroplasty a prospective randomized clinical controlled RSA trial.
  • 2014
  • Ingår i: Knee. - : Elsevier BV. - 1873-5800. ; 21:2, s. 396-401
  • Tidskriftsartikel (refereegranskat)abstract
    • A concern that arises with any change in technique is whether it affects the long-term implant stability. The objective of this study was to evaluate the early migration, measured by radiostereometric analysis (RSA), and the functional outcome of the Triathlon™ cemented knee prosthesis, operated on with or without a tourniquet. During the last decades RSA has emerged as a way to assess prosthetic fixation and long time prognosis. The method has been used extensively in both hip and knee arthroplasty.
  •  
29.
  • Nilsdotter, Anna, et al. (författare)
  • A 5 year prospective study of patient-relevant outcomes after total knee replacement.
  • 2009
  • Ingår i: Osteoarthritis and Cartilage. - : Elsevier BV. - 1063-4584. ; 17, s. 601-606
  • Tidskriftsartikel (refereegranskat)abstract
    • OBJECTIVE: To prospectively describe self-reported outcomes up to 5 years after total knee replacement (TKR) in Osteoarthritis (OA) and to study which patient-relevant factors may predict outcomes for pain and physical function (PF). METHODS: 102 consecutive patients with knee OA, 63 women and 39 men, mean age 71 (51-86) assigned for TKR at the Department of Orthopaedics at Lund University Hospital were included in the study. The self-administered questionnaires Knee injury and Osteoarthritis Outcome Score (KOOS) and SF-36 were mailed preoperatively and 6 months, 12 months and at 5 years postoperatively. RESULTS: Response rate at 5 years was 86%. At 6 months significant improvement was seen in all KOOS and SF-36 scores (P<0.001). The percentage of patients performing more demanding functions related to sports and recreation increased postoperatively. The best postoperative result was reported at the 1 year follow-up. Compared to the 1 year follow-up, a significant (P
  •  
30.
  • Nilsdotter, Anna, et al. (författare)
  • Knee arthroplasty: are patients' expectations fulfilled?
  • 2009
  • Ingår i: Acta Orthopaedica. - : Medical Journals Sweden AB. - 1745-3682 .- 1745-3674. ; 80:1, s. 55-61
  • Tidskriftsartikel (refereegranskat)abstract
    • Background and purpose With an aging population expecting an active life after retirement, patients' expectations of improvement after surgery are also increasing. We analyzed the relationship between preoperative expectations and postoperative satisfaction and self-reported outcomes with regard to pain and physical function after knee arthroplasty. Patients and methods 102 patients (39 men) with knee osteoarthritis and who were assigned for TKR (mean age 71 (51-86) years) were investigated with KOOS, SF-36, and additional questions concerning physical activity level, expectations, satisfaction, and relevance of the outcome to the patient. These investigations took place preoperatively and postoperatively after 6 months, 1 year, and 5 years of follow-up. Results Response rate at 5 years was 86%. In general, the patients' preoperative expectations were higher than their postoperative ability. For example, 41% expected to be able to perform activities such as golfing and dancing while only 14% were capable of these activities at 5 years. Having high or low preoperative expectations with regard to walking ability or leisure-time activities had no influence on the KOOS scores postoperatively. 93% of the patients were generally satisfied 5 years postoperatively, while 87% were satisfied with the relief of pain and 80% with their improvement in physical function at that time. Interpretation With an expanding population of mentally alert elderly, we can expect that great demands will be put on joint replacements. This study shows that patients have high preoperative expectations concerning reduction of pain. To a considerable extent, these expectations are fulfilled after one year. Expectations concerning demanding physical activities are not fulfilled to the same degree; however, most patients reported general satisfaction with the outcome indicating that satisfaction is not equivalent to fulfilled expectations. Preoperative counseling should include realistic information on outcomes concerning physical function and pain relief.
  •  
31.
  • Roos, Ewa, et al. (författare)
  • Knee injury and Osteoarthritis Outcome Score (KOOS) - validation and comparison to the WOMAC in total knee replacement.
  • 2003
  • Ingår i: Health and Quality of Life Outcomes. - : Springer Science and Business Media LLC. - 1477-7525. ; 1:1, s. 17-17
  • Tidskriftsartikel (refereegranskat)abstract
    • BACKGROUND: The Knee injury and Osteoarthritis Outcome Score (KOOS) is an extension of the Western Ontario and McMaster Universities Osteoarthrtis Index (WOMAC), the most commonly used outcome instrument for assessment of patient-relevant treatment effects in osteoarthritis. KOOS was developed for younger and/or more active patients with knee injury and knee osteoarthritis and has in previous studies on these groups been the more responsive instrument compared to the WOMAC. Some patients eligible for total knee replacement have expectations of more demanding physical functions than required for daily living. This encouraged us to study the use of the Knee injury and Osteoarthritis Outcome Score (KOOS) to assess the outcome of total knee replacement. METHODS: We studied the test-retest reliability, validity and responsiveness of the Swedish version LK 1.0 of the KOOS when used to prospectively evaluate the outcome of 105 patients (mean age 71.3, 66 women) after total knee replacement. The follow-up rates at 6 and 12 months were 92% and 86%, respectively. RESULTS: The intraclass correlation coefficients were over 0.75 for all subscales indicating sufficient test-retest reliability. Bland-Altman plots confirmed this finding. Over 90% of the patients regarded improvement in the subscales Pain, Symptoms, Activities of Daily Living, and knee-related Quality of Life to be extremely or very important when deciding to have their knee operated on indicating good content validity. The correlations found in comparison to the SF-36 indicated the KOOS measured expected constructs. The most responsive subscale was knee-related Quality of Life. The effect sizes of the five KOOS subscales at 12 months ranged from 1.08 to 3.54 and for the WOMAC from 1.65 to 2.56. CONCLUSION: The Knee injury and Osteoarthritis Outcome Score (KOOS) is a valid, reliable, and responsive outcome measure in total joint replacement. In comparison to the WOMAC, the KOOS improved validity and may be at least as responsive as the WOMAC.
  •  
32.
  • Toksvig-Larsen, Sören, et al. (författare)
  • Bisphosphonate-coated external fixation pins appear similar to hydroxyapatite-coated pins in the tibial metaphysis and to uncoated pins in the shaft : a randomized trial
  • 2013
  • Ingår i: Acta Orthopaedica. - : Informa Healthcare. - 1745-3674 .- 1745-3682. ; 84:3, s. 314-318
  • Tidskriftsartikel (refereegranskat)abstract
    • Background and purpose External fixation pins tend to loosen with time, especially from cancellous bone. A coating that releases a bisphosphonate has been shown to improve the fixation of dental implants in humans. We now tested a bisphosphonate coating on steel pins for external fixation. The primary hypothesis was that coated pins would be better fixed in the diaphysis.Methods 20 patients with medial knee osteoarthritis underwent proximal tibial correction osteotomy with hemicallotasis. They received a pair of pins (Orthofix) in the tibial shaft, one bisphosphonate-coated and one uncoated. Another pair of pins was inserted in the metaphysis, near the joint. This pair was a bisphosphonate-coated pin and an HA-coated pin. All pins were inserted according to a random list. The pins were removed after the osteotomy had healed (8–15 weeks), and extraction torque served as the predetermined main outcome variable.Results No pins showed clinical signs of loosening. Removal torque for the shaft pins was 6.6 Nm (SD 2.2) for the bisphosphonate and 6.0 Nm (SD 2.5) for the uncoated (difference = 0.5, 95% CI: –0.03 to 1.3). Removal torque for the metaphyseal pins was 4.4 Nm (SD 1.3) for the bisphosphonate-coated and 4.2 Nm (SD 1.6) for the HA-coated (difference = 0.2, 95% CI: –0.5 to 1.0).Interpretation We could not show any improved cortical fixation, but the metaphyseal findings are striking. In a previous study on 19 patients with a similar layout, HA-coated and uncoated pins were compared. In the metaphysis, all 19 uncoated pins loosened before removal. It was concluded that uncoated pins could not be used in the metaphyseal region. The present results suggest that a bisphosphonate coating enables metaphyseal fixation similar to that of hydroxyapatite coatings, with no difference from uncoated pins in cortical bone.
  •  
33.
  • Toksvig-Larsen, Sören, et al. (författare)
  • Inferior fixation with a new pin design for external fixation: A randomized study in 50 patients operated on by the hemicallotasis technique.
  • 2008
  • Ingår i: Acta Orthopaedica. - : Medical Journals Sweden AB. - 1745-3682 .- 1745-3674. ; 79:1, s. 48-52
  • Tidskriftsartikel (refereegranskat)abstract
    • Background and purpose Tibial osteotomy by the hemicallotasis technique (HCO) requires strong pin fixation. We compared pin fixation in HCO using a new self-drilling XCaliber pin (Orthofix) with optimized thread and tip design, with the commonly used standard pin (Orthofix). Patients and methods 50 patients, mean age 51 (35-66) years, to be treated by HCO were randomized to standard pins or XCaliber pins. In the metaphyseal bone, hydroxyapatite-coated (HA-coated) pins were used in both types of pins. In the diaphyseal bone, non-coated pins were used. The torque forces for insertion and extraction (in Nm) were measured. Results The insertion torque was higher for both the proximal and distal standard pins (2.1 Nm (SD 0.9) and 7.0 Nm (1.3), respectively) than for the XCaliber pins (1.3 Nm (0.8) and 3.6 Nm (1.4)). The extraction torque force was higher for the proximal standard pins (4.3 Nm (3.1)) than for the proximal XCaliber pins (1.5 Nm (1.7)) (p < 0.001). The extraction torque for the distal standard pins was 1.9 Nm (2.0) and for the distal XCaliber pins it was 1.4 Nm (1.1). Interpretation The commonly used standard pin gives stronger fixation during the treatment of HCO.
  •  
34.
  •  
35.
  • Toksvig-Larsen, Søren, et al. (författare)
  • The Porous-Coated Anatomic Total Knee Experience. Special Emphasis on Complications and Wear
  • 1996
  • Ingår i: Journal of Arthroplasty. - 0883-5403. ; 1:11, s. 11-17
  • Tidskriftsartikel (refereegranskat)abstract
    • One hundred sixty knees in 141 patients with the Primary Porous-Coated Anatomic prosthesis (Howmedica, Rutherford, NJ) were evaluated after a follow-up period of 5.6 years (range, 1–10 years). One hundred six knees were in the latest follow-up evaluation, including clinical examination and a defined standing radiograph with a follow-up period of 6.3 years (range, 3–10 years). Survivorship analysis regarding the cumulative revision rate (including completion with a patellar component) was 0.88 at the 8-year and 0.84 at the 10-year follow-up examination. The clinical result was satisfying/good, with a mean Hospital for Special Surgery score of 83 (range, 39–97). Five percent had thinning greater than 30% of the tibial component. The wear was calculated to be 1.0 mm (range, 0–9 mm), including three revised tibial components with heavy wear. Excluding the revised cases, the wear was 0.7 mm.
  •  
36.
  •  
37.
  •  
38.
  •  
39.
  • van der Lelij, Thies J.N., et al. (författare)
  • Continued Stabilization of a Cementless 3D-Printed Total Knee Arthroplasty : Five-Year Results of a Randomized Controlled Trial Using Radiostereometric Analysis
  • 2023
  • Ingår i: The Journal of bone and joint surgery. American volume. - 1535-1386. ; 105:21, s. 1686-1694
  • Tidskriftsartikel (refereegranskat)abstract
    • BACKGROUND: Three-dimensional (3D) printing of highly porous orthopaedic implants aims to promote better osseointegration, thus preventing aseptic loosening. However, short-term radiostereometric analysis (RSA) after total knee arthroplasty (TKA) has shown higher initial migration of cementless 3D-printed tibial components compared with their cemented counterparts. Therefore, critical evaluation of longer-term tibial component migration is needed. We investigated migration of a cementless 3D-printed and a cemented tibial component with otherwise similar TKA design during 5 years of follow-up, particularly the progression in migration beyond 2 years postoperatively. METHODS: Seventy-two patients were randomized to a cementless 3D-printed Triathlon Tritanium (Stryker) cruciate-retaining (CR) TKA or a cemented Triathlon CR (Stryker) TKA implant. Implant migration was evaluated with RSA at baseline and postoperatively at 3 months and at 1, 2, and 5 years. The maximum total point motion (MTPM) of the tibial component was compared between the groups at 5 years, and progression in migration was assessed between 2 and 5 years. Individual implants were classified as continuously migrating if the MTPM was ≥0.1 mm/year beyond 2 years postoperatively. Clinical scores were evaluated, and a linear mixed-effects model was used to analyze repeated measurements. RESULTS: At 5 years, the mean MTPM was 0.66 mm (95% confidence interval [CI], 0.56 to 0.78 mm) for the cementless group and 0.53 mm (95% CI, 0.43 to 0.64 mm) for the cemented group (p = 0.09). Between 2 and 5 years, there was no progression in mean MTPM for the cementless group (0.02 mm; 95% CI, -0.06 to 0.10 mm) versus 0.07 mm (95% CI, 0.00 to 0.14) for the cemented group. One implant was continuously migrating in the cementless group, and 4 were continuously migrating in the cemented group. The clinical scores were comparable between the groups across the entire time of follow-up. CONCLUSIONS: No significant difference in mean migration was found at 5 years between the cementless and cemented TKA implants. Progression of tibial component migration was present beyond 2 years for the cemented implant, whereas the cementless implant remained stable after initial early migration. LEVEL OF EVIDENCE: Therapeutic Level I . See Instructions for Authors for a complete description of levels of evidence.
  •  
40.
  • VAN DER LELIJ, Thies J.N., et al. (författare)
  • Influence of marker-selection method in radiostereometric analysis of total knee arthroplasty on tibial baseplate migration patterns : a secondary analysis of a randomized controlled trial with 5-year follow-up
  • 2024
  • Ingår i: Acta Orthopaedica. - 1745-3674. ; 95, s. 157-165
  • Tidskriftsartikel (refereegranskat)abstract
    • Background and purpose — Different marker-selection methods are applied to represent implant and tibial seg-ments in radiostereometric analysis (RSA) studies of total knee arthroplasty (TKA). Either a consistent set of markers throughout subsequent RSA examinations (“consistent-marker method”) is used or all available markers at each follow-up (“all-marker method”). The aim of this secondary analysis was to compare marker-selection methods on individual and group level TKA migration results. Methods — Data from a randomized RSA study with 72 patients was included. Tibial baseplate migration was evalu-ated at 3 months, 1, 2, and 5 years postoperatively with both marker-selection methods. Additionally, migration was calculated using 5 fictive points, either plotted based on the consistent set of markers or all available markers. Results — Migration could be calculated with both marker-selection methods for 248 examinations. The same prosthesis and bone markers (n = 136), different prosthesis markers (n = 71), different bone markers (n = 21), or different prosthesis and bone markers (n = 20) were used. The mean difference in maximum total point motion (MTPM) between all examinations was 0.02 mm, 95% confidence interval –0.26 to 0.31 mm. 5 implants were classified as continuously migrating with the consistent-marker method versus 6 implants (same 5 plus one additional implant) with the all-marker method. Using fictive points, fewer implants were classified as continuously migrating in both marker-selection methods. Differences between TKA groups in mean MTPM were comparable with both marker-selection methods, also when fictive points were used. Conclusion — Estimated group differences in mean MTPM were similar between marker-selection methods, but individual migration results differed. The latter has implications when classifying implants for estimated risk of future loosening.
  •  
41.
  • van Hamersveld, Koen T., et al. (författare)
  • Marker-based versus model-based radiostereometric analysis of total knee arthroplasty migration : a reanalysis with comparable mean outcomes despite distinct types of measurement error
  • 2019
  • Ingår i: Acta Orthopaedica. - : Medical Journals Sweden AB. - 1745-3674 .- 1745-3682. ; 90:4, s. 366-372
  • Tidskriftsartikel (refereegranskat)abstract
    • Background and purpose — Pooling data of studies evaluating total knee arthroplasty migration using radiostereometric analysis (RSA) may be compromised when the RSA method used would influence estimated differences between groups. We therefore reanalyzed a marker-based RSA study with model-based RSA to assess possible limitations of each RSA method, including insert micromotions in modular TKA and their effect on estimated group differences. Patients and methods — All patients had received a cemented Triathlon implant (Stryker, Mahwah, NJ, USA) with either an all-polyethylene (n = 29) or a metal-backed (n = 28) tibial component. The latter group was reanalyzed with model-based RSA. Precision of each RSA method was calculated using double examinations. Bland–Altman plots were constructed to determine the limits of agreement between the 2 RSA methods. Polyethylene insert micromotion was quantified by measuring migration with respect to the metal tray. Finally, analyses of the original study were repeated with the model-based RSA results. Results — Systematic differences were found in translations between marker-based and model-based RSA as a result of different reference origins being used for migration calculations. Micromotions of the polyethylene insert within the metal tray were negligibly small. Mean migration results were comparable between marker-based and model-based RSA when using the same reference origin, even though conclusions on individual patients may differ between RSA methods due to various types of measurement error (e.g., marker occlusion and model-fit inaccuracies). Interpretation — At least for the studied TKA design, pooling mean migration data of different RSA methods appears justified. For translations, however, adjustments should be made to correct for differences in reference origin. Migration patterns of individual patients may differ as a result of distinct types of measurement error.
  •  
42.
  • Van Hamersveld, Koen T., et al. (författare)
  • Migration of all-polyethylene compared with metal-backed tibial components in cemented total knee arthroplasty : A randomized controlled trial
  • 2018
  • Ingår i: Acta Orthopaedica. - : Medical Journals Sweden AB. - 1745-3674 .- 1745-3682. ; 89:4, s. 412-417
  • Tidskriftsartikel (refereegranskat)abstract
    • Background and purpose — With a rapidly increasing population in need of total knee arthroplasty (TKA), there is renewed interest in cost-saving all-polyethylene designs. Differences between metal-backed and all-polyethylene designs in initial component migration assessed by radiostereometric analysis (RSA), a proven predictor for late aseptic loosening, have been scantily reported. The purpose of this study was to compare implant migration and clinical outcomes of all-polyethylene tibial components versus metal-backed trays of similar geometrical shape. Patients and methods — In this randomized controlled trial, 59 patients received a cemented Triathlon condylar-stabilizing implant (Stryker, Mahwah, NJ, USA) with either an all-polyethylene (n = 29) or a metal-backed tibial component (n = 30). RSA measurements and clinical scores (the Knee Society Score, Forgotten Joint Score, and Knee Osteoarthritis and Injury Outcome Score) were evaluated at baseline and postoperatively at 3, 12, and 24 months. A linear mixed-effects model was used to analyze the repeated measurements. Results — A statistically significant difference in mean migration after 2 years was found in favor of the all-polyethylene group, with a mean maximum total point motion of 0.61 mm (95% CI 0.49–0.74) versus 0.81 mm (95% CI 0.68–0.96) for the cemented group (p = 0.03). However, this difference was smaller and not statistically significant after post hoc adjustment for surgeon effect. Both groups showed comparable improvements on all clinical outcome scores over time. Interpretation — The Triathlon all-polyethylene tibial component showed less migration, suggesting a lower risk of late loosening as compared with its metal-backed counterpart. However, the found surgeon effect warrants further investigation.
  •  
43.
  • van Hamersveld, Koen T., et al. (författare)
  • Risk Factors for Tibial Component Loosening : A Meta-Analysis of Long-Term Follow-up Radiostereometric Analysis Data
  • 2021
  • Ingår i: Journal of Bone and Joint Surgery. American volume. - : NLM. - 0021-9355 .- 1535-1386. ; 103:12, s. 1115-1124
  • Tidskriftsartikel (refereegranskat)abstract
    • BACKGROUND: Radiostereometric analysis (RSA) is a highly accurate tool to detect implant migration and predict loosening following total knee arthroplasty (TKA). However, little is known about the predisposing risk factors for implant migration, nor which migration profile should be considered physiological (i.e., merely part of an implant-settling phase) and which should be considered pathological (i.e., having a high probability for implant loosening). By pooling individual participant data from long-term follow-up RSA studies, we aimed to identify predisposing risk factors for tibial component loosening.METHODS: Individual data were collected for 630 patients from 11 RSA studies. The repeated measurements were analyzed with use of a linear mixed-effects model, determining the effect of age, sex, body mass index, diagnosis, preoperative and postoperative limb alignment, and prosthesis characteristics on tibial component migration over time, taking into account the clustering of patients within studies.RESULTS: High initial migration was found to result in early mechanical loosening in 18 cases (2.9%) and septic loosening in 2 cases (0.3%), whereas stabilization of high initial migration occurred in 17 cases (2.7%). Late loosening occurred in 13 cases (2.1%). All other 580 cases (92.1%) showed early stabilization and remained stable over time. Mixed-effects model analyses showed that for cemented prostheses, sex, diagnosis, and posterior cruciate ligament type had an effect on migration, but these differences were nonsignificant when analyzing migration from 3 months onwards. Uncemented prostheses aligned in varus showed more migration than neutrally and valgus-aligned TKAs (p = 0.031), and this difference increased over time (p < 0.001). Significantly higher migration was observed following uncemented TKA without an osseointegration-promoting surface (p < 0.001).CONCLUSIONS: For cemented prostheses, increased migration during the first 3 postoperative months was observed for female patients, patients with rheumatoid arthritis, and patients who underwent a posterior-stabilized TKA. For uncemented prostheses, both postoperative varus alignment of the lower limb and the absence of an osseointegration-promoting surface significantly increased postoperative tibial component migration.LEVEL OF EVIDENCE: Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.
  •  
44.
  • W-Dahl, Annette, et al. (författare)
  • A 2-year prospective study of patient-relevant outcomes in patients operated on for knee osteoarthritis with tibial osteotomy
  • 2005
  • Ingår i: BMC Musculoskeletal Disorders. - : Springer Science and Business Media LLC. - 1471-2474. ; 6
  • Tidskriftsartikel (refereegranskat)abstract
    • Background: Tibial osteotomy is a treatment for younger and/or physically active patients suffering from uni-compartmental knee osteoarthritis. The open wedge osteotomy by the hemicallotasis technique includes the use of external fixation. The use of external fixation has several advantages, as early mobilization and the opportunity for optimal correction. However, the hemicallotasis technique has also been described as a cumbersome procedure for the patient. The aim of this study was to prospectively evaluate patient-relevant outcomes during the first 2 postoperative years. Especially the treatment period, during which external fixation was used, was closely monitored. Methods: In an uncontrolled study, fifty-eight consecutive patients, 30 men and 28 women ( mean age 54 years) were operated on by the hemicallotasis technique were evaluated with the patient-relevant outcome measure Knee injury and Osteoarthritis Outcome Score (KOOS) preoperatively, during the treatment with external fixation, one week after removal of the external fixation, at 6 months, and at one and two years postoperatively. Results: At the 2-year postoperative follow-up, all subscales of the KOOS were improved ( p < 0.001), mostly in pain ( 41 - 80 on a 0 - 100 worst to best scale) and knee-related quality of life ( 21 61 on a 0 - 100 worst to best scale), compared to the preoperative status. Significant improvements in pain and other symptoms, function of daily life and quality of life were seen already during the treatment period ( mean 98 +/- 18 days) with the external fixation. More demanding functions such as kneeling, squatting, jumping and running, were improved first after extraction of the external fixation device and the pins. Conclusion: Tibial osteotomy by the hemicallotasis technique yields large improvement in self-rated pain, function and quality of life, which persists over two years. Surprisingly, large improvements occurred already during the immediate post-operative period when the external fixation was still used.
  •  
45.
  • W-Dahl, Annette, et al. (författare)
  • Association between knee alignment and knee pain in patients surgically treated for medial knee osteoarthritis by high tibial osteotomy. A one year follow-up study.
  • 2009
  • Ingår i: BMC Musculoskeletal Disorders. - : Springer Science and Business Media LLC. - 1471-2474. ; 10:Dec 8
  • Tidskriftsartikel (refereegranskat)abstract
    • BACKGROUND: The association between knee alignment and knee pain in knee osteoarthritis (OA) is unclear. High tibial osteotomy, a treatment option in knee OA, alters load from the affected to the unaffected compartment of the knee by correcting malalignment. This surgical procedure thus offers the possibility to study the cross-sectional and longitudinal association of alignment to pain. The aims were to study 1) the preoperative association of knee alignment to preoperative knee pain and 2) the association of change in knee alignment with surgery to change in knee pain over time in patients operated on for knee OA by high tibial osteotomy. METHODS: 182 patients (68% men) mean age 53 years (34 - 69) with varus alignment having tibial osteotomy by the hemicallotasis technique for medial knee OA were consecutively included. Knee alignment was assessed by the Hip-Knee-Ankle (HKA) angle from radiographs including the hip and ankle joints. Knee pain was measured by the subscale pain (0 - 100, worst to best scale) of the Knee injury and Osteoarthritis Outcome Score (KOOS) preoperatively and at one year follow-up. To estimate the association between knee alignment and knee pain multivariate regression analyses were used. RESULTS: Mean preoperative varus alignment was 170 degrees (153 - 178) and mean preoperative KOOS pain was 42 points (3 - 86). There was no association between preoperative varus alignment and preoperative KOOS pain, crude analysis 0.02 points (95% CI -0.6 - 0.7) change in pain with every degree of HKA angle, adjusted analysis 0.3 points (95% CI -1.3 - 0.6).The mean postoperative knee alignment was 184 degrees (171 - 185). The mean change in knee alignment was 13 degrees (0 - 30). The mean change in KOOS pain was 32 (-16 - 83). There was neither any association between change in knee alignment and change in KOOS pain over time, crude analysis 0.3 point (95% CI -0.6 - 1.2), adjusted analysis 0.4 points (95% CI 0.6 - 1.4). CONCLUSION: We found no association between knee alignment and knee pain in patients with knee OA indicating that alignment and pain are separate entities, and that the degree of preoperative malalignment is not a predictor of knee pain after high tibial osteotomy.
  •  
46.
  • W-Dahl, Annette, et al. (författare)
  • Cigarette smoking delays bone healing: A prospective study of 200 patients operated on by the hemicallotasis technique
  • 2004
  • Ingår i: Acta Orthopaedica Scandinavica. - : Medical Journals Sweden AB. - 0001-6470. ; 75:3, s. 51-347
  • Tidskriftsartikel (refereegranskat)abstract
    • Abstract in UndeterminedBackground Cigarette smoking is known to impede bone healing. The hemicallotasis technique is based on an external fixation and delayed healing prolongs treatment and increases the risk of further complications. Patients and methods 200 patients, 34 smokers and 166 nonsmokers, operated on by the hemicallotasis technique in the proximal tibia for deformities of the knee (knee arthrosis in 186 patients) were consecutively studied. We recorded their preoperative smoking habits, postoperative complications and the duration of treatment with external fixation. Results Half of the smokers and one fifth of the nonsmokers developed complications. Their mean time in external fixation was 96 (SD 20) days. Smokers required an average of 16 days more in external fixation. Delayed healing and pseudoarthrosis were commoner in smokers than nonsmokers. The risk ratio for smokers to develop complications was 2.5, as compared to nonsmokers.
  •  
47.
  • W-Dahl, Annette, et al. (författare)
  • Infection prophylaxis: a prospective study in 106 patients operated on by tibial osteotomy using the hemicallotasis technique.
  • 2006
  • Ingår i: Archives of Orthopaedic and Trauma Surgery. - : Springer Science and Business Media LLC. - 1434-3916 .- 0936-8051. ; 126:7, s. 441-447
  • Tidskriftsartikel (refereegranskat)abstract
    • Introduction Tibial osteotomy by the hemicallotasis technique is a clean elective operation. With external fixation pins inserted, close to the knee joint, the infection prophylaxis should be considered. The primary aim was to investigate the differences in the postoperative use of antibiotics during the time in external fixation between administrating prophylactic antibiotics for 3 days or as a single dose in patients operated on by the hemicallotasis technique for knee deformities. Secondary aims were to study the differences in pin-site infection rate and grade and complications. Material and methods A total of 106 consecutive patients of mean age 52 years (range 18-69) operated on by the hemicallotasis technique for knee deformities were included in this prospective study. Sixty patients were prescribed prophylactic antibiotics for 3 days and 46 patients as a single dose. Chlorhexidine (5 mg/ml) in alcohol (70% ethanol) was used as cleansing agent in the pin-site care. The power of the study was calculated to 80% to detect a difference in the postoperative use of antibiotics for 7 days during the treatment in external fixation. Results There were no differences in postoperative use of antibiotics between 3 days administration or a single dose of prophylactic antibiotics. This was the case with infection rate and grade, positive bacterial cultures, presence of Staphylococcus aureus, nor positive culturing from the tip of the pins at removal. Neither were there any differences in numbers of loose pins and complications. Conclusion There were no differences between 3 days of administration of prophylactic antibiotics and one single dose. One single dose of prophylactic antibiotics is appropriate together with a pin-site concept preventing pin-site infection in patients operated on by hemicallotasis osteotomy.
  •  
48.
  • W-Dahl, Annette, et al. (författare)
  • No clinical benefits using a new design of pins for external fixation: a randomized study in 50 patients operated on by the hemicallotasis technique.
  • 2008
  • Ingår i: Archives of Orthopaedic and Trauma Surgery. - : Springer Science and Business Media LLC. - 1434-3916 .- 0936-8051. ; 128:7, s. 661-667
  • Tidskriftsartikel (refereegranskat)abstract
    • BACKGROUND: Pin-site infection and pin loosening are complications that can cause discomfort to the patients. The purpose of present study was to evaluate pin-site infection, pain, and the use of medications using the XCaliber pin (Orthofix) with optimized thread and tip design, and the commonly used standard pin (Orthofix) during the procedure of hemicallotasis osteotomy (HCO). MATERIAL AND METHODS: Fifty patients of mean age 51 (35-66) years treated with HCO were randomized to standard pins (Orthofix) or XCaliber pins (Orthofix). Hydroxyapatite-coated pins were used in the metaphyseal bone and non-coated pins in the diaphyseal bone in both groups. Pin sites, pain, and the use of medications were evaluated weekly during the HCO. RESULTS: At week 7 the patients in the XCaliber group had more pain at rest [19 (22) vs. 5 (5) mm, P = 0.01] and during activity [32 (32) vs. 12 (13) mm, P = 0.02] and used more paracetamol (2,100 vs. 925 mg, P = 0.04) than those in the standard group, with similar differences, until the extraction of the pins. There was no difference in the use of antibiotics [10.5 (14.5) days (XCaliber) vs. 7 (7.5) days (standard) (P = 0.16)]. CONCLUSION: The commonly used standard pin has important clinical- and patient-related benefits.
  •  
49.
  • W-Dahl, Annette, et al. (författare)
  • No delayed bone healing in Swedish male oral snuffers operated on by the hemicallotasis technique: A cohort study of 175 patients.
  • 2007
  • Ingår i: Acta Orthopaedica. - : Medical Journals Sweden AB. - 1745-3682 .- 1745-3674. ; 78:6, s. 791-794
  • Tidskriftsartikel (refereegranskat)abstract
    • Background and purpose The effect of oral snuff on bone healing is virtually unknown. In vitro data have indicated that delay in bone healing in smokers may be the result of components of smoke other than nicotine. We compared the time for bone healing after high tibial osteotomy in snuffers, smokers, and in control subjects who did not use snuff or cigarettes. Patients and methods 175 male patients comprising 41 smokers, 21 oral snuff users, and 113 non-smokers/ non-snuffers, all of whom were operated on for knee deformity by tibial osteotomy using the hemicallotasis technique (HCO) between 2000 and 2005, were included in a consecutive manner. Preoperative tobacco use, postoperative complications, and treatment time in external fixation were documented. Results There was no delayed healing in the oral snuff users. The mean time in external fixation for all patients was 94 days (SD 20). Oral snuff users had the shortest time in external fixation (87 days (SD11)) compared to smokers (100 days (SD 25)) (p = 0.03) and non-smokers/non-snuffers (93 days (SD 14)). The risk ratio for smokers developing complications was 6.1 (95% CI: 1.2-36.4) compared with oral snuff users. Interpretation Our findings indicate that the use of oral snuff does not delay bone healing or increase the risk of postoperative complications, which cigarette smoking does, in patients operated on by the hemicallotasis technique.
  •  
50.
  • W-Dahl, Annette, et al. (författare)
  • No difference between daily and weekly pin site care: a randomized study of 50 patients with external fixation.
  • 2003
  • Ingår i: Acta Orthopaedica Scandinavica. - : Medical Journals Sweden AB. - 0001-6470. ; 74:6, s. 704-708
  • Tidskriftsartikel (refereegranskat)abstract
    • Introduction: We investigated whether there were any differences in the frequency and severity of pin site infections by performing pin site care daily or once a week. We studied patients operated on for gonarthrosis by the hemicallotasis technique, using hydroxyapatite-coated pins in the metaphyseal bone and standard pins in the diaphyseal bone. Patients and methods: 50 patients were prospectively randomized to daily (nÊ= 27) or weekly (nÊ= 23) pin site care. We evaluated pin sites, the occurrence of pain (VAS), the use of antibiotics and analgesics and complications every week. Bacterial cultures were taken from each pin site at 1, 6 and 10 weeks and from the pins on removal. Results: We found no differences between daily or weekly pin site care as regards the frequency and severity of pin site infections, pain, or the use of antibiotics and analgesics. Grade I infections (Checketts-Otterburns classification) occurred around 11% of the pins and grade II infections around 4%. 70% of the bacterial cultures were negative. The most frequent bacteria were coagulase negative staphylococcus and corynebacterium. Antibiotics were given an average of 47 days. More problems occurred around the proximal pins. 5/200 (all proximal) pins were clinically loose on removal. Interpretation: Pin site care once a week seems appropriate.
  •  
Skapa referenser, mejla, bekava och länka
  • Resultat 1-50 av 53
Typ av publikation
tidskriftsartikel (49)
konferensbidrag (2)
doktorsavhandling (1)
bokkapitel (1)
Typ av innehåll
refereegranskat (48)
övrigt vetenskapligt/konstnärligt (5)
Författare/redaktör
Toksvig-Larsen, Söre ... (52)
W-Dahl, Annette (16)
Nelissen, Rob G. H. ... (8)
Lindstrand, Anders (7)
Ryd, Leif (7)
Marang-Van De Mheen, ... (7)
visa fler...
Hansson, Ulrik (6)
Kaptein, Bart L. (6)
Tägil, Magnus (5)
Roos, Ewa (5)
Harsten, Andreas (5)
Van Hamersveld, Koen ... (5)
Aspenberg, Per (3)
Harding, Anna Kajsa (3)
Hasan, Shaho (3)
Nilsdotter, Anna (2)
Nilsson, Kjell G (2)
Mertens, Fredrik (2)
Robertsson, Otto (2)
Jonsson, Kjell (2)
Kehlet, H (2)
Giannini, S. (2)
Catani, F (2)
Ensini, A (2)
Leardini, A (2)
Bragonzoni, L (2)
Little, David (2)
Broberg Palmgren, Ka ... (1)
Geijer, Mats, 1957 (1)
Lohmander, Stefan (1)
Cooper, C. (1)
Johnell, Olof (1)
Höglund, Mattias (1)
Gustafsson, Johan (1)
Broberg, Karin (1)
Lidgren, Lars (1)
Bandholm, Thomas (1)
Åstrand, Jörgen (1)
Ljung, P. (1)
Stenström, Anders (1)
Tallini, Giovanni (1)
Cucca, G (1)
Dalen, Tore (1)
Tsonaka, Roula (1)
Jorn, Lars Peter (1)
Hjartarson, Hjörtur (1)
Kehlet, Henrik (1)
Henricson, Anders, 1 ... (1)
Toksvig-Larsen, Söre ... (1)
Hjartarson, Hjörtur ... (1)
visa färre...
Lärosäte
Lunds universitet (51)
Umeå universitet (2)
Linköpings universitet (2)
Göteborgs universitet (1)
Uppsala universitet (1)
Språk
Engelska (53)
Forskningsämne (UKÄ/SCB)
Medicin och hälsovetenskap (51)

År

Kungliga biblioteket hanterar dina personuppgifter i enlighet med EU:s dataskyddsförordning (2018), GDPR. Läs mer om hur det funkar här.
Så här hanterar KB dina uppgifter vid användning av denna tjänst.

 
pil uppåt Stäng

Kopiera och spara länken för att återkomma till aktuell vy