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Van Ooij B.,University of Amsterdam | Van Ooij B.,Orthopedic Research Center Amsterdam | Van Dijk C.N.,University of Amsterdam | Van Dijk C.N.,Orthopedic Research Center Amsterdam
Regional Anesthesia and Pain Medicine | Year: 2011

BACKGROUND AND OBJECTIVES: Continuous femoral nerve block in patients undergoing total knee arthroplasty (TKA) improves and shortens postoperative rehabilitation. The primary aim of this study was to investigate whether the addition of sciatic nerve block to continuous femoral nerve block will shorten the time-to-discharge readiness. METHODS: Ninety patients undergoing TKA were prospectively randomized to 1 of 3 groups: patient-controlled analgesia via femoral nerve catheter alone (F group) or combined with a single-injection (Fs group) or continuous sciatic nerve block (FCS group) until the second postoperative day. Discharge readiness was defined as the ability to walk and climb stairs independently, average pain on a numerical rating scale at rest lower than 4, and no complications. In addition, knee function, pain, supplemental morphine requirement, local anesthetic consumption, and postoperative nausea and vomiting (PONV) were evaluated. RESULTS: Median time-to-discharge readiness was similar: F group, 4 days (range, 2-16 days); Fs group, 4 days (range, 2-7 days); and FCS group, 4 days (range, 2-9 days; P = 0.631). No significant differences were found regarding knee function, local anesthetic consumption, or postoperative nausea and vomiting. During the day of surgery, pain was moderate to severe in the F group, whereas Fs and FCS groups experienced minimal pain (P < 0.01). Patients in the F group required significantly more supplemental morphine on the day of surgery and the first postoperative day. Until the second postoperative day, pain was significantly less in the FCS group (P < 0.01). CONCLUSIONS: A single-injection or continuous sciatic nerve block in addition to a femoral nerve block did not influence time-to-discharge readiness. A single-injection sciatic nerve block can reduce severe pain on the day of the surgery, whereas a continuous sciatic nerve block reduces moderate pain during mobilization on the first 2 postoperative days. Copyright © 2011 by American Society of Regional Anesthesia and Pain Medicine.


Van Engelen S.J.P.M.,VU University Amsterdam | Wajer Q.E.,VU University Amsterdam | Van Der Plaat L.W.,Orthopedic Research Center Amsterdam | Doets H.C.,Slotervaart Hospital | And 2 more authors.
Clinical Biomechanics | Year: 2010

Background: This study examined metabolic energy cost and external mechanical work for step-to-step transitions after tibiotalar arthrodesis, and the effect of MBT rocker bottom shoes. Methods: Oxygen uptake, forceplate and kinematic data were recorded in 18 controls and 15 patients while walking at a fixed speed of 1.25 m/s in three walking conditions: barefoot, normal walking shoes and MBT rocker bottom shoes. Metabolic energy cost, external mechanical work, and the roll-over shape of the ankle-foot complex were analyzed. Findings: Tibiotalar arthrodesis leads to higher metabolic energy cost during walking. During step-to-step transitions positive work during push-off with the impaired ankle was decreased but negative work during collision was not affected. The roll-over shape of the ankle-foot complex did not differ between groups and shoe conditions. However, both in patients and controls rocker bottom shoes did lead to decreased positive work at push-off and increased negative work at collision and consequently higher metabolic energy cost of walking. Interpretation: External mechanical work for step-to-step transitions is not different between patients and controls and could not account for the higher metabolic energy cost in patients. Apparently, patients adopt a different walking strategy that limits step-to-step transition cost but nevertheless induces a higher metabolic energy cost. Despite restricted ankle movement, patients retain a normal roll-over shape of the ankle-foot complex. MBT shoes do not affect roll-over shape and appear to have a counterproductive effect on step-to-step transition cost and walking economy. © 2010 Elsevier B.V. All rights reserved.


Van Oldenrijk J.,Orthopedic Research Center Amsterdam | Molleman J.,Orthopedic Research Center Amsterdam | Klaver M.,Orthopedic Research Center Amsterdam | Poolman R.W.,Joint Research | Haverkamp D.,Slotervaartziekenhuis
Acta Orthopaedica | Year: 2014

Background and purpose - The aim of short-stem total hip arthroplasty is to preserve proximal bone stock for future revisions, to improve biomechanical reconstruction, and to make minimally invasive approaches easier. It is therefore being increasingly considered to be a sound alternative to conventional total hip arthroplasty, especially for young and active patients. However, it is still unknown whether survival rates of short-stem hips match current standards. We made a systematic summary of reported overall survival after short-stem total hip arthroplasty. Materials and methods - We conducted a systematic review of English, French, German, and Dutch literature. 2 assessors independently identified clinical studies on short-stem hip arthroplasty. After recalculating reported revision rates, we determined whether each implant had a projected revision rate of 10% or less at 10 years of follow-up or a revision rate per 100 observed component years of 1 or less. Stems were classified as "collum", "partial collum", or "trochanter- sparing". Results and Interpretation - We found 49 studies, or 51 cohorts, involving 19 different stems. There was a large increase in recent publications. The majority of studies included had a follow-up of less than 5 years. We found a large number of observational studies on "partial collum" and "trochanter-sparing" stems, demonstrating adequate survival rates at medium-term follow-up. Clinical evidence from "collum stem" studies was limited to a small number of studies with a medium-term follow-up period. These studies did not show a satisfactory overall survival rate. © Nordic Orthopaedic Federation.


Van Eekeren I.C.M.,Orthopedic Research Center Amsterdam | Reilingh M.L.,Orthopedic Research Center Amsterdam | Van Dijk C.N.,Orthopedic Research Center Amsterdam
Sports Medicine | Year: 2012

An osteochondral defect (OD) is a lesion involving the articular cartilage and the underlying subchondral bone. ODs of the talus can severely impact on the quality of life of patients, who are usually young and athletic. The primary treatment for ODs that are too small for fixation, consists of arthroscopic debridement and bone marrow stimulation. This article delineates levels of activity, determines times for return to activity and reviews the factors that affect rehabilitation after arthroscopic debridement and bone marrow stimulation of a talar OD. Articles for review were obtained from a search of the MEDLINE database up to January 2012 using the search headings 'osteochondral defects', 'bone marrow stimulation', 'sportsactivity', 'rehabilitation', various other related factors and 'talus'. English-, Dutch- and German-language studies were evaluated.The review revealed that there is no consensus in the existing literature about rehabilitation times or return-to-sports activity times, after treatment with bone marrow stimulation of ODs in the talus. Furthermore, scant research has been conducted on these issues. The literature also showed that potential factors that aid rehabilitation could include youth, lower body mass index, smaller OD size, mobilization and treatment with growth factors, platelet-rich plasma, biphosphonates, hyaluronic acid and pulse electromagnetic fields. However, most studies have been conducted in vitro or on animals. We propose a scheme, whereby return-to-sports activity is divided into four phases of increasing intensity: walking, jogging, return to non-contact sports (running without swerving) and return to contact sports (running with swerving and collision). We also recommend that research, conducted on actual sportsmen, of recovery times after treatment of talar ODs is warranted. © 2012 Springer International Publishing AG. All rights reserved.


Tuijthof G.J.M.,Orthopedic Research Center Amsterdam | Tuijthof G.J.M.,Technical University of Delft | Visser P.,Orthopedic Research Center Amsterdam | Sierevelt I.N.,Orthopedic Research Center Amsterdam | And 2 more authors.
Clinical Orthopaedics and Related Research | Year: 2011

Background: Some commercial simulators are available for training basic arthroscopic skills. However, it is unclear if these simulators allow training for their intended purposes and whether the perception of usefulness relates to level of experience. Questions/purposes: We addressed the following questions: (1) Do commercial simulators have construct (times to perform tasks) and face validity (realism), and (2) is the perception of usefulness (educational value and user-friendliness) related to level of experience? Methods: We evaluated two commercially available virtual reality simulators (Simulators A and B) and recruited 11 and nine novices (no arthroscopies), four and four intermediates (one to 59 arthroscopies), and seven and nine experts (> 60 arthroscopies) to test the devices. To assess construct validity, we recorded the median time per experience group for each of five repetitions of one identical navigation task. To assess face validity, we used a questionnaire to judge up to three simulator characteristic tasks; the questionnaire asked about the realism, perception of educational value, and perception of user-friendliness. Results: We observed partial construct validity for Simulators A and B and considered face validity satisfactory for both simulators for simulating the outer appearance and human joint, but barely satisfactory for the instruments. Simulators A and B had equal educational value according to the participants. User-friendliness was judged better for Simulator B although both were graded satisfactory. The perception of usefulness did not differ with level of experience. Conclusions: Our observations suggest training on either simulator is reasonable preparation for real-life arthroscopy, although there is room for improvement for both simulators. These simulators provide training in surgical skills without compromising patient safety. © 2011 The Author(s).


Kerkhoffs G.M.M.J.,Orthopedic Research Center Amsterdam | Van Dijk C.N.,Orthopedic Research Center Amsterdam
Foot and Ankle Clinics | Year: 2013

High-level athletes have significantly greater load and demand on their ankle joints than the average population. Therefore, treatment of acute lateral ankle ligament ruptures in the high-demanding athlete is a challenge. This article reviews the treatment of acute lateral ankle ruptures in athletes, with special emphasis on the role of surgical treatment. © 2013.


Kok A.C.,Orthopedic Research Center Amsterdam | Tuijthof G.J.M.,Orthopedic Research Center Amsterdam | Tuijthof G.J.M.,Technical University of Delft | Den Dunnen S.,Technical University of Delft | And 5 more authors.
Clinical Orthopaedics and Related Research | Year: 2013

Background: Débridement and bone marrow stimulation is an effective treatment option for patients with talar osteochondral defects. However, whether surgical factors affect the success of microfracture treatment of talar osteochondral defects is not well characterized. Questions/purposes: We hypothesized (1) holes that reach deeper into the bone marrow-filled trabecular bone allow for more hyaline-like repair; and (2) a larger number of holes with a smaller diameter result in more solid integration of the repair tissue, less need for new bone formation, and higher fill of the defect. Methods: Talar osteochondral defects that were 6 mm in diameter were drilled bilaterally in 16 goats (32 samples). In eight goats, one defect was treated by drilling six 0.45-mm diameter holes in the defect 2 mm deep; in the remaining eight goats, six 0.45-mm diameter holes were punctured to a depth of 4 mm. All contralateral defects were treated with three 1.1-mm diameter holes 3 mm deep, mimicking the clinical situation, as internal controls. After 24 weeks, histologic analyses were performed using Masson-Goldner/Safranin-O sections scored using a modified O'Driscoll histologic score (scale, 0-22) and analyzed for osteoid deposition. Before histology, repair tissue quality and defect fill were assessed by calculating the mean attenuation repair/healthy cartilage ratio on Equilibrium Partitioning of an Ionic Contrast agent (EPIC) micro-CT (μCT) scans. Differences were analyzed by paired comparison and Mann-Whitney U tests. Results: Significant differences were not present between the 2-mm and 4-mm deep hole groups for the median O'Driscoll score (p = 0.31) and the median of the μCT attenuation repair/healthy cartilage ratios (p = 0.61), nor between the 0.45-mm diameter and the 1.1-mm diameter holes in defect fill (p = 0.33), osteoid (p = 0.89), or structural integrity (p = 0.80). Conclusions: The results indicate that the geometry of microfracture holes does not influence cartilage healing in the caprine talus. Clinical Relevance: Bone marrow stimulation technique does not appear to be improved by changing the depth or diameter of the holes. © 2013 The Association of Bone and Joint Surgeons®.


Tuijthof G.J.M.,Orthopedic Research Center Amsterdam | Tuijthof G.J.M.,Technical University of Delft | van Sterkenburg M.N.,Orthopedic Research Center Amsterdam | Sierevelt I.N.,Orthopedic Research Center Amsterdam | And 3 more authors.
Knee Surgery, Sports Traumatology, Arthroscopy | Year: 2010

The demand for high quality care is in contrast to reduced training time for residents to develop arthroscopic skills. Thereto, simulators are introduced to train skills away from the operating room. In our clinic, a physical simulation environment to Practice Arthroscopic Surgical Skills for Perfect Operative Real-life Treatment (PASSPORT) is being developed. The PASSPORT concept consists of maintaining the normal arthroscopic equipment, replacing the human knee joint by a phantom, and integrating registration devices to provide performance feedback. The first prototype of the knee phantom allows inspection, treatment of menisci, irrigation, and limb stressing. PASSPORT was evaluated for face and construct validity. Construct validity was assessed by measuring the performance of two groups with different levels of arthroscopic experience (20 surgeons and 8 residents). Participants performed a navigation task five times on PASSPORT. Task times were recorded. Face validity was assessed by completion of a short questionnaire on the participants' impressions and comments for improvements. Construct validity was demonstrated as the surgeons (median task time 19.7 s [8.0-37.6]) were more efficient than the residents (55.2 s [27.9-96.6]) in task completion for each repetition (Mann-Whitney U test, P<0.05). The prototype of the knee phantom sufficiently imitated limb outer appearance (79%), portal resistance (82%), and arthroscopic view (81%). Improvements are required for the stressing device and the material of cruciate ligaments. Our physical simulation environment (PASSPORT) demonstrates its potential to evolve as a training modality. In future, automated performance feedback is aimed for. © 2009 Springer-Verlag.


Breugem S.J.M.,Orthopedic Research Center Amsterdam | van Ooij B.,Orthopedic Research Center Amsterdam | Haverkamp D.,Orthopedic Research Center Amsterdam | Sierevelt I.N.,Orthopedic Research Center Amsterdam | van Dijk C.N.,Orthopedic Research Center Amsterdam
Knee Surgery, Sports Traumatology, Arthroscopy | Year: 2014

Purpose: The presence of anterior knee pain remains one of the major complaints following total knee arthroplasty (TKA). Since the introduction of the mobile TKA, many studies have been performed and only a few show a slight advantage for the mobile. In our short-term follow-up study, we found less anterior knee pain in the posterior stabilized mobile knees compared to the posterior stabilized knees. The concept of self-alignment and the results from our short-term study led us to form the hypothesis that the posterior stabilized mobile knee leads to a lower incidence of anterior knee pain compared to the posterior stabilized fixed knee. This study was designed to see whether this difference remains after 7.9 years in the follow-up. A secondary line of enquiry was to see whether one was superior to the other regarding pain, function, quality of life and survival. Methods: This current report is a 6-10-year (median 7.9 years) follow-up study of the remaining 69 patients with a cemented three-component TKA for osteoarthritis in a prospective, randomized, double-blinded clinical trial. Results: In the posterior stabilized group, five of the 40 knees (13 %) versus five of the 29 posterior stabilized mobile group (17 %) experienced anterior knee pain. No differences were observed with regard to ROM, VAS, Oxford 12-item knee questionnaire, SF-36, HSS patella, Kujala or the AKSS score. Patients with anterior knee pain reported more pain, lower levels of the AKSS, HSS patella and the Kujala scores than the patients without anterior knee pain. Conclusion: In the current clinical practice, the appearance of anterior knee pain persists as a problem; simply changing to a mobile bearing does not seem to be the solution. The posterior stabilized mobile total knee did not sustain the advantage of less anterior knee pain, compared with the posterior stabilized fixed total knee arthroplasty. Level of evidence: Therapeutic study, Level II. © 2012 Springer-Verlag Berlin Heidelberg.


Tuijthof G.J.M.,Technical University of Delft | Tuijthof G.J.M.,Orthopedic Research Center Amsterdam | Fruhwirt C.,Austrian Center for Medical Innovation and Technology | Kment C.,Austrian Center for Medical Innovation and Technology
Medical Engineering and Physics | Year: 2013

Minimally invasive surgery poses high demands on tool design. The goal was to measure the influence of drill bit geometry on maximum thrust forces required for drilling, and compare this relative to the known influence of feed rate and bone composition.Blind holes were drilled perpendicular to the iliac crest up to 10. mm depth in cadaveric pelvic bones of 20 pigs (adolescent) and 11 goats (full grown) with eight substantially different drill bits of ∅ 3-3.2. mm. Subsequently, boreholes were drilled perpendicular to the ilium with the same drill bits at three different feed rates (0.58. mm/s, 0.83. mm/s, 1.08. mm/s). The mean maximum thrust force ranges from 10 to 110. N for cortical bone, and from 3 to 65. N for trabecular bone. The results show that both drill bit geometry and feed rate have a significant influence on the maximum thrust forces, with a dominant influence of drill bit geometry in terms of shape of the flutes, sharpness of cutting edges and value of point angle. The differences in thrust forces between cortical and trabecular bone are substantial for all measured conditions. The measured values can be used for drill design. © 2012 IPEM.

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