Leendert Blankevoort
University of Amsterdam
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Clinical Orthopaedics and Related Research | 1994
J. Heegaard; P. F. Leyvraz; A. Van Kampen; L. Rakotomanana; P. J. Rubin; Leendert Blankevoort
During knee flexion, the human patella moves along a complex path resulting from the combined actions of articular contact and soft-tissue stabilization. The current study is an attempt to characterize the role of these soft structures on patellar kinematics. To this end, the three-dimensional patellar motion during full knee flexion was accurately measured before and after partial dissection of the joint. The guiding role of the femoral groove prevailed over soft-tissue action through most of the range of motion. At full extension, however, when the patella and the femur were not in contact, the influence of the retinaculi was most noticeable, highlighting the unstable behavior of the patella near extension. The differences between the intact and dissected knee kinematics suggested that control over patellar motion is ensured by the transverse soft-tissue structures near extension and by the patellofemoral joint geometry during further flexion.
Acta Orthopaedica | 2005
Daniel Haverkamp; Stefan J. M. Breugem; Inger N. Sierevelt; Leendert Blankevoort; C Nick van Dijk
Background In 1998, the Oxford 12-item knee questionnaire was developed by Dawson et al. as a self-administered disease- and site-specific questionnaire, specifically developed for knee arthroplasty patients. Since then, it has proven to be an effective outcome questionnaire, and is widely used. Despite the positive psychometric properties for the Total Knee Arthroplasty (TKA) population, the 12-item knee questionnaire has only been translated into a few languages. We thus translated and validated the Oxford 12-item knee questionnaire for the Dutch population. Methods and results After translation according to a forward/backward protocol, 174 knee arthroplasty patients were asked to answer the questionnaire together with an SF-36, an AKSS and a VAS. The reliability, validity, content validity and the sensitivity to change were all tested. Our Dutch version of the Oxford 12-item knee questionnaire achieved excellent scores in all of these properties. Interpretation The Dutch Oxford 12-item knee questionnaire proved to be an excellent evaluation instrument for the Dutch orthopedic surgeon and can be used for all total knee arthroplasty patients.
Acta Orthopaedica Scandinavica | 2003
Gino M. M. J. Kerkhoffs; Peter A. A. Struijs; René K Marti; Leendert Blankevoort; Willem J. J. Assendelft; C. Niek van Dijk
Our aim with this systematic review was to assess the effectiveness of various functional treatments for acute ruptures of the lateral ankle ligament in adults. We performed an electronic database search using MEDLINE, EMBASE, COCHRANE CONTROLLED TRIAL REGISTER and CURRENT CONTENTS. We evaluated randomized clinical trials describing skeletally mature subjects with an acute rupture of the lateral ankle ligament and compared functional treatments for inclusion in this study. 9 trials met our inclusion criteria. Two reviewers independently assessed the quality of these trials and extracted relevant data on treatment outcome. Where appropriate, results of comparable studies were pooled. Individual and pooled statistics are reported as relative risks (RR) for dichotomous outcome and (weighted) mean differences ((W)MD) for continuous outcome measures with 95% confidence intervals (95% CI). Heterogeneity between the trials was tested using a standard chi-square test. Persistent swelling at short-term follow-up was less with lace-up ankle support than with semi-rigid ankle support (RR 4.2 95% CI 1.3-14), an elastic bandage (RR 5.5; 95% CI 1.7-18) and tape (RR 4.1; 95% CI 1.2-14). A semi-rigid ankle support required a shorter period for return to work than an elastic bandage (WMD 4.2; 95% CI 2.4-6.1) (p = 0.7). One trial reported better results for subjective instability using the semi-rigid ankle support than the elastic bandage (RR 8.0; 95% CI 1.0-62). Treatment with tape resulted in more complications, mostly skin problems, than that with an elastic bandage (RR 0.1; 95% CI 0.0-0.8). We found no other statistically significant differences. We conclude that an elastic bandage is a less effective functional treatment. Lace-up supports seem better, but the data are insufficient as a basis for definite conclusions.
Clinical Orthopaedics and Related Research | 2008
Stefan J. M. Breugem; Inger N. Sierevelt; Matthias U. Schafroth; Leendert Blankevoort; Gerard R. Schaap; C. Niek van Dijk
AbstractAnterior knee pain is one of the major short-term complaints after TKA. Since the introduction of the mobile-bearing TKA, numerous studies have attempted to confirm the theoretical advantages of a mobile-bearing TKA over a fixed-bearing TKA but most show little or no actual benefits. The concept of self-alignment for the mobile bearing suggests the posterior-stabilized mobile-bearing TKA would provide a lower incidence of anterior knee pain compared with a fixed-bearing TKA. We therefore asked whether the posterior-stabilized mobile-bearing knee would in fact reduce anterior knee pain. We randomized 103 patients scheduled for cemented three-component TKA for osteoarthrosis in a prospective, double-blind clinical trial. With a 1-year followup, more patients experienced persistent anterior knee pain in the posterior-stabilized fixed-bearing group (10 of 53, 18.9%) than in the posterior-stabilized mobile-bearing group (two of 47, 4.3%). No differences were observed for range of motion, visual analog scale for pain, Oxford 12-item questionnaire, SF-36, or the American Knee Society score. The posterior-stabilized mobile-bearing knee therefore seems to provide a short-term advantage compared with the posterior-stabilized fixed-bearing knee. Level of Evidence: Level I, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.
Foot & Ankle International | 2011
Markus Knupp; Sjoerd A. S. Stufkens; Christian J. van Bergen; Leendert Blankevoort; Lilianna Bolliger; C. N. van Dijk; Beat Hintermann
Background: Distal tibia coronal plane malalignment predisposes the ankle joint to asymmetric load. The purpose of this cadaveric study was to quantify changes in pressure and force transfer in an ankle with a supramalleolar deformity. Materials and Methods: Seventeen cadaveric lower legs were loaded with 700 N after creating supramalleolar varus and valgus deformities. The fibula was left intact in 11 specimens and osteotomized in six. Tekscan© sensors were used to measure the tibiotalar pressure characteristics. Results: In isolated supramalleolar deformity, the center of force and peak pressure moved in an anteromedial direction for valgus and posterolateral direction for varus deformities. The change was in an anteromedial direction for varus and in a posterolateral direction for valgus deformities in specimens with an osteotomized fibula. Conclusion: Two essentially different groups of varus and valgus deformities of the ankle joint need to be distinguished. The first group is an isolated frontal plane deformity and the second group is a frontal plane deformity with associated incon-gruency of the ankle mortise. Clinical Relevance: Our findings underline the complexity of asymmetric osteoarthritis of the ankle joint. In addition, results from this study provide useful information for future basic research on coronal plane deformity of the hindfoot and for determining appropriate surgical approaches.
Acta Orthopaedica Scandinavica | 2002
René K Marti; Gino M. M. J. Kerkhoffs; Mario Maas; Leendert Blankevoort
We treated 46 consecutive patients (47 elbows) suffering from posttraumatic contracture of the elbow joint with operative release. A lateral approach was used to perform a capsulectomy after release of the extensor muscles in 23 elbows. An additional medial approach was used to excise ulnar adhesions and perform a more extensive capsulectomy and an ulnar nerve neurolysis in 24 elbows. Postoperative rehabilitation consisted of immediate passive range-of-motion exercises. The results were assessed after average 10 (2-18) years. Before surgery, the mean active arc of motion was 45 (SD 36) degrees, which improved to 99 (SD 34) degrees after release. 7 patients had transient ulnar paresthesia, 4 recurrent stiffness, which did not become worse after surgery, 1 was reoperated on and 2 developed a post-operative infection, which responded to antibiotic treatment after a few months. No patient suffered from joint instability, or an increase in pain. 44 patients were satisfied with the result at the latest follow-up. We found similar improvement in both treatment groups.
Journal of Athletic Training | 2012
Michel P. J. van den Bekerom; Peter A. A. Struijs; Leendert Blankevoort; Lieke Welling; C. Niek van Dijk; Gino M. M. J. Kerkhoffs
CONTEXT Ankle sprains are common problems in acute medical care. The variation in treatment observed for the acutely injured lateral ankle ligament complex in the first week after the injury suggests a lack of evidence-based management strategies for this problem. OBJECTIVE To analyze the effectiveness of applying rest, ice, compression, and elevation (RICE) therapy begun within 72 hours after trauma for patients in the initial period after ankle sprain. STUDY SELECTION Eligible studies were published original randomized or quasi-randomized controlled trials concerning at least 1 of the 4 subtreatments of RICE therapy in the treatment of acute ankle sprains in adults. DATA SOURCES MEDLINE, Cochrane Clinical Trial Register, CINAHL, and EMBASE. The lists of references of retrieved publications also were checked manually. DATA EXTRACTION We extracted relevant data on treatment outcome (pain, swelling, ankle mobility or range of motion, return to sports, return to work, complications, and patient satisfaction) and assessed the quality of included studies. If feasible, the results of comparable studies were pooled using fixed- or random-effects models. DATA SYNTHESIS After deduction of the overlaps among the different databases, evaluation of the abstracts, and contact with some authors, 24 potentially eligible trials remained. The full texts of these articles were retrieved and thoroughly assessed as described. This resulted in the inclusion of 11 trials involving 868 patients. The main reason for exclusion was that the authors did not describe a well-defined control group without the intervention of interest. CONCLUSIONS Insufficient evidence is available from randomized controlled trials to determine the relative effectiveness of RICE therapy for acute ankle sprains in adults. Treatment decisions must be made on an individual basis, carefully weighing the relative benefits and risks of each option, and must be based on expert opinions and national guidelines.
American Journal of Sports Medicine | 2006
Daniel Haverkamp; Inger N. Sierevelt; Stefan J. M. Breugem; Kim Lohuis; Leendert Blankevoort; C. Niek van Dijk
Background For knee-related surgery, there is a great demand for internationally useable subjective scoring systems. Before such measurements can be used, they should be translated and validated for the population they are used on. For the Dutch population, only the Western Ontario and McMaster Universities Osteoarthritis Index and Oxford 12 Questionnaire have been validated. However, these scores can only be used regarding osteoarthritis of the knee. In 2001, the International Knee Documentation Committee presented the Subjective Knee Form, which is a knee-specific rather than a disease-specific questionnaire. Study Design Cohort study (diagnosis/symptom prevalence); Level of evidence, 2. Methods The authors describe the translation procedure and validation of the Dutch Subjective Knee Form. After a forward backward translation protocol, the reliability, validity, and content validity were tested. The responses of 145 consecutive knee patients on 2 questionnaires containing the Short Form–36, Western Ontario and McMaster Universities Osteoarthritis Index, Oxford 12 Questionnaire score, a visual analog scale, and the Dutch International Knee Documentation Committee Subjective Knee Form were used. Reliability was tested by measuring the test-retest reliability and internal consistency. Validity was tested by correlating the questionnaire to the other outcome measurements, and content validity was tested by measuring the floor and ceiling effects. Results The reliability proved excellent with an intraclass coefficient of 0.96 for test-retest. Internal consistency was strong (Cronbach [.alpha],. 92). The construct, convergent, and divergent validities were good. The content validity was good; no floor or ceiling effect occurred. Conclusion The validation procedure shows that the Dutch International Knee Documentation Committee Subjective Knee Form is an excellent evaluation instrument for Dutch patients with knee-related injuries.
Journal of Bone and Joint Surgery-british Volume | 2011
Sjoerd A. S. Stufkens; C. J. A. van Bergen; Leendert Blankevoort; C. N. van Dijk; Beat Hintermann; Markus Knupp
It has been suggested that a supramalleolar osteotomy can return the load distribution in the ankle joint to normal. However, due to the lack of biomechanical data, this supposition remains empirical. The purpose of this biomechanical study was to determine the effect of simulated supramalleolar varus and valgus alignment on the tibiotalar joint pressure, in order to investigate its relationship to the development of osteoarthritis. We also wished to establish the rationale behind corrective osteotomy of the distal tibia. We studied 17 cadaveric lower legs and quantified the changes in pressure and force transfer across the tibiotalar joint for various degrees of varus and valgus deformity in the supramalleolar area. We assumed that a supramalleolar osteotomy which created a varus deformity of the ankle would result in medial overload of the tibiotalar joint. Similarly, we thought that creating a supramalleolar valgus deformity would cause a shift in contact towards the lateral side of the tibiotalar joint. The opposite was observed. The restricting role of the fibula was revealed by carrying out an osteotomy directly above the syndesmosis. In end-stage ankle osteoarthritis with either a valgus or varus deformity, the role of the fibula should be appreciated and its effect addressed where appropriate.
The Journal of Rheumatology | 2008
Eric E.J. Raven; Daniel Haverkamp; Inger N. Sierevelt; Douwe O. van Montfoort; Ruud G. Pöll; Leendert Blankevoort; Paul P. Tak
Objective The Disability of Arm, Shoulder and Hand (DASH) questionnaire is a tool for measuring physical function and symptoms of the upper extremity. Although widely used, it is not validated for rheumatoid arthritis (RA). In this study the DASH was validated for this patient group. Methods In total, 102 patients participated in this study. For the validation, the questionnaires of the DASH, the Health Assessment Questionnaire (HAQ), the Medical Outcomes Study Short Form-36 (SF-36), and the Arthritis Impact Measurement Scale (AIMS2) were used. Patients were examined clinically before completing the questionnaires. Pain was scored by each patient using a visual analog scale (VAS). The DiseaseActivity Score (DAS28) was obtained and grip strength was measured. Reliability was tested by a second DASH questionnaire after 2 days. Validity was tested using a Pearson correlation analysis for the relevant domains of the questionnaires and for the clinical aspects. Results The reliability of the DASH was excellent (intraclass correlation coefficient 0.97). Internal consistency was strong (Cronbach’s alpha 0.97). Validity was proven with excellent results for Pearson correlation with the relevant domains of the questionnaires: HAQ, r = 0.88; SF-36, r = 0.70; and AIMS2, r = 0.85. The clinical scores had a relatively low correlation with the DASH (DAS28, r = 0.42; and grip strength, r = 0.41–0.48), except for the VAS (r = 0.60–0.65). Conclusion The DASH is a reliable and valid questionnaire in patients with RA. It can be used as a measurement tool of physical disability of the upper extremity.