Low revision rate throughout the adoption of the direct superior approach in primary total hip arthroplasty: an analysis based on 1551 total hip arthroplasties from the Dutch Arthroplasty Register.

BACKGROUND: Recently, surgeons introduced a minimally invasive modification on the classic posterolateral approach (PLA) in total hip arthroplasty (THA): the direct superior approach (DSA). We investigated the association between surgeon's experience and the risk of early revision of the DSA in primary THA, using data from the Dutch Arthroplasty Register (LROI). METHODS: We retrieved all primary THAs performed using the DSA in 4 hospitals between 2016 and 2022 (n = 1551). Procedures were sorted in 5 groups using the date of operation and number of previous procedures per surgeon: 1-25; 26-50; 51-75; 76-100; >100. Subsequently, data from different surgeons were pooled together and the risk of revision was calculated via a multilevel time-to-event analysis. RESULTS: The overall revision rate was 1.5% after a mean follow-up of 2 years. Patients from the 1-25 group had comparable risks of revision compared to patients in the >100 group (hazard ratio [HR] 1.0 [CI, 0.3-3.2]). The risk for patients in groups 26-50, 51-75 and 75-100 was also not statistically different from the >100 group (resp. HR 1.5 [CI, 0.5-5.0], 1.8 [CI, 0.5-6.4] and 0.5 [CI, 0.1-4.0]). Main reasons of revision were dislocation (0.5%) and infection (0.4%). CONCLUSIONS: We did not identify an association between the surgeon's experience and the early risk of revision for the DSA in primary THA in the Netherlands. The DSA seems safe in the early adoption phases with a low risk of revision due to dislocation and revision for all other causes.

Mid-term results of cemented hip arthroplasties through the direct anterior approach in the lateral decubitus position: a retrospective cohort study.

BACKGROUND: Reports show a high complication rate when starting with the Direct Anterior Approach (DAA) in a supine position for hip arthroplasty. The DAA with the patient in lateral decubitus position may avoid this problem because it supposedly provides better visibility, especially on the femoral side. However, this approach did show a rather high complication rate during the adoption of the approach at 1 year follow up in our previous report. We were interested what the overall 7 year survival estimate would be and whether improvement could be seen with growing experience. METHODS: A cohort of patients undergoing total hip arthroplasty right from the start of applying the DAA in lateral decubitus position was analysed. RESULTS: In total 175 hip prostheses (162 patients) were evaluated. The 7-year survival estimate was 95.1%, 95 CI: 91.8-98.4%. In 6 of 8 revisions there was aseptic loosening of the stem. By dividing the cohort into 3 consecutive groups in time we did not see a significantly improving revision rate. CONCLUSIONS: In our experience, the adoption of the direct anterior approach in lateral decubitus position caused a relatively low 7-year survival estimate without an apparent decrease with growing experience, however given the low number of cases further research is needed to investigate the long-term risk of adopting a new approach.

Revision risk by using the direct superior approach (DSA) for total hip arthroplasty compared with postero-lateral approach: early nationwide results from the Dutch Arthroplasty Register (LROI).

BACKGROUND AND PURPOSE: The direct superior approach (DSA) is a modification of the classic posterolateral approach (PLA) for total hip arthroplasty (THA), in which the iliotibial band and short external rotators are spared. The revision rate of the DSA has not been investigated previously using arthroplasty registry data. We examined the reasons and risk of revision of the DSA, compared with the direct anterior approach (DAA) and PLA. PATIENTS AND METHODS: In this population-based cohort study we included 175,543 primary THAs performed between 2014 and 2020 (PLA, n = 117,576; DAA, n = 56,626; DSA, n = 1,341). Competing risk survival analysis and multivariable Cox proportional hazard analyses, adjusted for potential confounders, were performed. RESULTS: After 3 years, crude revision rates due to any reason were 2.1% (95% confidence interval [CI] 1.3-3.3) for DSA, and 2.9% (CI 2.8-3.0) for PLA. Crude dislocation revision rates were 0.3% (CI 0.1-0.8) for DSA, versus 1.0% (CI 0.9-1.0) for PLA. Dislocation revision rate for DSA did not differ from DAA (0.3% [CI 0.2-0.3]). Multivariable Cox regression analysis demonstrated no overall difference in revision rates for the DSA (HR 0.6 [CI 0.4-1.09) compared with the PLA. Lower risk of revision due to dislocation was found in patients operated on through the DSA (HR 0.3 [0.1-0.9]) compared with the PLA. CONCLUSION: Early nationwide results suggest that the DSA for total hip arthroplasty seems to show a tendency towards a lower risk of revision for dislocation but no overall reduced revision risk compared with the PLA.

Ten-year results of a prospective cohort of large-head metal-on-metal total hip arthroplasty : a concise follow-up of a previous report.

AIMS: Large-diameter metal-on-metal (MoM) total hip arthroplasty (THA) has demonstrated unexpected high failure rates and pseudotumour formation. The purpose of this prospective cohort study is to report ten-year results in order to establish revision rate, prevalence of pseudotumour formation, and relation with whole blood cobalt levels. METHODS: All patients were recalled according to the guidelines of the Dutch Orthopaedic Association. They underwent clinical and radiographical assessments (x-ray and CT scan) of the hip prosthesis and whole blood cobalt ion measurements. Overall, 94 patients (95 hips) fulfilled our requirements for a minimum ten-year follow-up. RESULTS: Mean follow-up was 10.9 years (10 to 12), with a cumulative survival rate of 82.4%. Reason for revision was predominantly pseudotumour formation (68%), apart from loosening, pain, infection, and osteolysis. The prevalence of pseudotumour formation around the prostheses was 41%, while our previous report of this cohort (with a mean follow-up of 3.6 years) revealed a 39% prevalence. The ten-year revision-free survival with pseudotumour was 66.7% and without pseudotumour 92.4% (p < 0.05). There was poor discriminatory ability for cobalt for pseudotumour formation. CONCLUSION: This prospective study reports a minimum ten-year follow-up of large-head MoM THA. Revision rates are high, with the main reason being the sequelae of pseudotumour formation, which were rarely observed after five years of implantation. Blood ion measurements show limited discriminatory capacity in diagnosing pseudotumour formation. Our results evidence that an early comprehensive follow-up strategy is essential for MoM THA to promptly identify and manage early complications and revise on time. After ten years follow-up, we do not recommend continuing routine CT scanning or whole cobalt blood measurements, but instead enrolling these patients in routine follow-up protocols for THA. Cite this article: Bone Jt Open 2022;3(1):61-67.

Symptomatic venous thromboembolism after trauma surgery : a study on 56.884 procedures.

Patients undergoing trauma surgery are at significant risk for developing thromboembolism. Venous thromboembolism rates, especially after less common surgical procedures are unknown. The purpose of this study is to establish data on the incidence of venous thromboembolism in trauma practice following a surgical procedure. All surgical trauma procedures between 2006 and 2011 were identified within the Achmea Health Database. This database records medical care to persons insured at the Achmea health insurance company. This is the largest health insurance company in the Netherlands. In the year following the surgical procedure we analyzed if a claim was filed concerning a deep venous thrombosis or pulmonary embolism. 56.884 surgical trauma procedures were included in the analysis and followed for one year thereafter. Venous thromboembolism development was raised most markedly until 100 days after the surgical procedure. Relatively high incidences of venous thromboembolism were found after surgical lower extremity and pelvic procedures. The present large database study provides a comprehensive view on the epidemiology of venous thromboembolism after different traumatic injuries requiring a surgical procedure.

CT radiation dose reduction in patients with total hip arthroplasties using model-based iterative reconstruction and orthopaedic metal artefact reduction.

OBJECTIVE: To evaluate the impact of radiation dose reduction on image quality in patients with metal-on-metal total hip arthroplasties (THAs) using model-based iterative reconstruction (MBIR) combined with orthopaedic metal artefact reduction (O-MAR). MATERIALS AND METHODS: Patients with metal-on-metal THAs received a pelvic CT with a full (FD) and a reduced radiation dose (RD) with -20%, -40%, -57%, or -80% CT radiation dose respectively, when assigned to group 1, 2, 3, or 4 respectively. FD acquisitions were reconstructed with iterative reconstruction, iDose4. RD acquisitions were additionally reconstructed with iterative model-based reconstruction (IMR) levels 1-3 with different levels of noise suppression. CT numbers, noise and contrast-to-noise ratios were measured in muscle, fat and bladder. Subjective image quality was evaluated on seven aspects including artefacts, osseous structures, prosthetic components and soft tissues. RESULTS: Seventy-six patients were randomly assigned to one of the four groups. While reducing radiation dose by 20%, 40%, 57%, or 80% in combination with IMR, CT numbers remained constant. Compared with iDose4, the noise decreased (p < 0.001) and contrast-to-noise ratios increased (p < 0.001) with IMR. O-MAR improved CT number accuracy in the bladder and reduced noise in the bladder, muscle and fat (p < 0.01). Subjective image quality was rated lower on RD IMR images than FD iDose4 images on all seven aspects (p < 0.05) and was not related to the applied radiation dose reduction. CONCLUSION: In RD IMR with O-MAR images, CT numbers remained constant, noise decreased and contrast-to-noise ratios between muscle and fat increased compared with FD iDose4 with O-MAR images in patients with metal-on-metal THAs. Subjective image quality reduced, regardless of the degree of radiation dose reduction.

Skin depigmentation along lymph vessels of the lower leg following local corticosteroid injection for interdigital neuroma.

Steroid injection is frequently used in the treatment of interdigital neuroma and has a high rate of success. We report the case of a patient who develops skin depigmentation at the injection site and linear streaks of depigmentation over the foot, the ankle and half way up to the knee after a steroid injection for interdigital neuroma. Minor disadvantages such as subcutaneous fat atrophy and depigmentation of the skin at the injection site are well known problems following steroid injection. Depigmentation of the skin with a lymphatic distribution in the foot after steroid injection for interdigital neuroma however, has not yet been reported before. This complication is a serious aesthetic problem and clinicians should be aware of this complication when treating patients with steroid injections for interdigital neuroma.

Long-term outcomes of the Bi-Metric proximally hydroxyapatite-coated femoral stem.

PURPOSE: Promising clinical results and survival rates have been reported for the Bi-Metric proximally hydroxyapatite (HA)-coated femoral stem in short- and mid-term studies. In this study we evaluated the long-term survival as well as clinical and radiological results of this stem. METHODS: From 1992 to 1998 we prospectively included 112 consecutive patients who received a total hip arthroplasty (THA) with an uncemented proximally HA-coated Bi-Metric femoral component (Biomet).At 3 months, 1 year and thereafter every 2 to 3 years, patients were clinically and radiologically monitored. Primary endpoint was revision of the stem for any reason. Secondary endpoints were survival of the cup and THA, radiological characteristics and clinical scores (HHS, HOOS, SF-36 and VAS). RESULTS: Median follow-up was 20 (16-22.25) years. Median age at surgery was 52 (22-63) years. At final follow-up, survival analysis showed an all-cause stem survival of 96.8% (95% CI, 93.3-100). Median HHS scores improved from 57 preoperatively to 94 at final follow-up (p<0.001). At final follow-up the median HOOS score was 80 (9-100); median SF-36 score 71 (18-100); median VAS pain score at rest 0 (0-6) and during activity 0 (0-10). CONCLUSIONS: In this prospective cohort study the 20-year survival rate of the Bi-Metric proximally HA-coated femoral stem was excellent.

CT-based quantification of bone stock in large head metal-on-metal unilateral total hip replacements.

PURPOSE: To explore ipsilateral and contralateral acetabular roof bone stock density in unilateral large head MoM THA whether there is a significant lower acetabular bone stock in the hip with a metal-on-metal (MoM) total hip replacement compared to the contralateral side. Second part of this study is to examine if there are any associates with regard to potential bone stock density difference. MATERIALS & METHODS: A database of 317 patients with unilateral metal-on-metal (MoM) total hip replacements was set up retrospectively for this study. On computed tomography scans, conducted after a relative short in situ time period averaging 2.8 years, regions-of-interests were drawn in the trabecular bone of the acetabulum to measure average Hounsfield Units (HU). HU differences were calculated and tested by Wilcoxon signed-rank test. Univariate analysis was conducted to examine associates of potential bone loss. RESULTS: In a population of 317 patients (156 male, 161 female) with an average age of 61.9 ± 7.8, the median HU on the side of the MoM replacement was 123.3 (7.6-375.4). On the contralateral side, median HU was 144.7 (-0.4 to 332.8). The median HU difference was 21.4 after a mean post-operative in situ time of 2.8 years. The Wilcoxon signed-rank test proved a significant difference (p<0.001). Univariate analyses show that the in situ time of the MoM THA has a significant correlation with the bone density difference. CONCLUSION: Results show a significant lower bone density at the acetabular roof at the side of the prosthesis compared with the contralateral side after short in situ time of the MoM THA in patients with unilateral MoM total hip replacements. In our patient population, the in situ time showed a significant association with the acetabular bone density difference. As acetabular roof bone stock measurements are feasible and show temporal decline this could become an important parameter to be used in orthopedic decision making for revision surgery.

Development and first validation of a simplified CT-based classification system of soft tissue changes in large-head metal-on-metal total hip replacement: intra- and interrater reliability and association with revision rates in a uniform cohort of 664 arthroplasties.

OBJECTIVE: After implantation of a metal-on-metal total hip arthroplasty (MoM THA), a large incidence of pseudotumor formation has been described recently. Several centers have invited patients for follow-up in order to screen for pseudotumor formation. The spectrum of abnormalities found by CT in MoM THA patients can be unfamiliar to radiologists and orthopedic surgeons. Previously, a CT five-point grading scale has been published. In this paper, a simplification into a three-point classification system gives insight in the morphological distinction of abnormalities of the postoperative hip capsule in MoM implants in relation to the decision for revision. The reliability of this simplified classification regarding intra- and interrater reliability and its association with revision rate is investigated and discussed. MATERIALS AND METHODS: All patients who underwent MoM THA in our hospital were invited for screening. Various clinical measures and CT scan were obtained in a cross-sectional fashion. A decision on revision surgery was made shortly after screening. CT scans were read in 582 patients, of which 82 patients were treated bilaterally. CT scans were independently single read by two board-certified radiologists and classified into categories I-V. In a second meeting, consensus was obtained. Categories were subsequently rubricated in class A (categories I and II), B (category III), and C (categories IV and V). Intra- and inter-radiologist agreement on MoM pathology was assessed by means of the weighted Cohen's kappa. Categorical data were presented as n (%), and tested by means of Fisher's exact test. Continuous data were presented as median (min-max) and tested by means of Mann-Whitney U test (two group comparison) or Kruskal-Wallis test (three group comparison). Logistic regression analysis was performed in order to study independence of CT class for association with revision surgery. Univariate statistically significant variables were entered in a multiple model. All statistical analysis was performed two-tailed using alpha 5% as the significance level. RESULTS: In total, 664 scores from 664 MoM hips obtained by two observers were available for analyses. Interobserver reliability for the non-simplified version (I-V) was κw = 0.71 (95% CI: 0.62-0.79), which indicates good agreement between the two musculoskeletal radiologists. Intra- and interobserver reliability for the simplified version (A-C) were respectively κw 0.78 (95% CI: 0.68-0.87), and κw = 0.71 (95% CI: 0.65-0.76). This indicates good agreement within and between the two observers. The simplified A-C version is significantly associated with revision exclusively due to MoM pathology, in both patients with unilateral MoM THA (p < 0.001) and patients with bilateral MoM THA (p < 0.044). The simplified A-C version is associated with several clinical measures. In patients with unilateral MoM THA, with or without contralateral THA, in situ time (p < 0.008), cobalt and chromium (p < 0.001) were statistically significant. In patients with bilateral MoM, cobalt (p < 0.001) and chromium (p < 0.027) were statistically significant. Revision is significantly associated with cup size (p < 0.001), anteversion of the cup (p < 0.004), serum ion levels of cobalt and chromium (p < 0.001) and the adapted classification system (p < 0.001). In univariate logistic regression analysis on revision, cup, anteversion of the cup, cobalt-chromium ion serum levels, and the simplified (A-C) CT category system were statistically significant. The simplified (A-C) CT category system was an independent associate of revision, in several multiple logistic regression models. CONCLUSIONS: The presented simplified CT grading system (A-C) in its first clinical validation on 48- and 64-multislice systems is reliable, showing good intra- and interrater reliability and is independently associated with revision surgery.

Revision of a single type of large metal head metal-on-metal hip prosthesis.

Large-head metal-on-metal (MoM) total hip arthroplasties were introduced because of their purported advantages. Inflammatory pseudotumours occasionally occur after MoM hip arthroplasty and often lead to revision. The purpose of this study was to assess the outcome of revision of large-head MoM total hip arthroplasties after an extensive screening protocol for all MoM articulations with a minimum 2 year follow-up. We identified 50 hips that had undergone large-head MoM total hip arthoplasty and required revision at a mean of 44 months after index operation. Of these, 38 were revised for pseudotumours, 7 for loosening, 2 for infection and 3 for instability. There was bone loss in 44 hips. The majority were revised to a 28 mm metal or ceramic head on a polyethylene-cemented cup. In 12 patients there was a complication. There was a decrease of whole blood cobalt from 20.8 µg/L preoperatively to 1.8 µg/L 1 year after revision. We found 6 residual masses on routine postoperative CT scans. The indication for revision of this cohort is inevitable but the clinical outcome 2 years after revision for pseudotumour is disappointing. Revising a MoM hip arthroplasty to a conventional cemented polyethylene or dual-mobility cup with bone impaction grafting and a 28 mm head can adequately treat the high ion levels and probably the disease of ARMD.

Clinical manifestations in ten patients with asymptomatic metal-on-metal hip arthroplasty with very high cobalt levels.

Reports of adverse reactions to metal particle debris with metal-on-metal (MoM) hip arthroplasty have increased recently. Apart from the formation of pseudotumours and higher revision rates, another major cause for concern are the systemic effects of metal ions. Several effects of elevated systemic cobalt ions have been reported (e.g., myocardial and neurological effects, hypothyroidism). All 643 patients who underwent a stemmed large head MoM total hip replacement in our clinic were screened with repeated whole blood samples of metal ions (cobalt, chromium). We included ten asymptomatic unrevised patients with the highest cobalt concentrations, determined at a minimum of three years after implantation. These patients were subjected to an extensive neurological and cardiological screening protocol. In addition, blood samples were taken to assess renal and thyroid function. Ten patients with a cobalt level of 18-153 µg/L (mean 46.8 µg/L) were included. Nine patients were female, mean age was 65 years (range 56-75). The mean follow-up period was 4.2 years (range 3.0-6.1). Seven patients had bilateral stemmed MoM hip arthroplasty. No signs or symptoms of neurological dysfunction, cardiomyopathy, or renal or thyroid dysfunction could be identified or attributed to elevated cobalt levels. The clinical relevance of this study is that after short-term follow-up highly elevated blood cobalt levels do not cause systemic effects in our population. Hence in asymptomatic patients metal ions appear not to be a significant factor in the decision of when to revise a MoM large head total hip replacement.

Deep vein thrombosis after arthroscopic anterior cruciate ligament reconstruction: a prospective cohort study of 100 patients.

PURPOSE: To establish the incidence of venous thromboembolic complications as detected by bilateral complete compression ultrasonography (CCUS) after arthroscopic anterior cruciate ligament (ACL) reconstruction without thromboprophylaxis. METHODS: We performed a prospective cohort study to establish the incidence of venous thromboembolic complications after arthroscopic ACL reconstruction, as detected by bilateral CCUS at 14 days (range, 11 to 17 days) postoperatively. One hundred consecutive patients underwent bilateral extended ultrasonography. RESULTS: One hundred predominantly European patients with a mean age of 30 ± 10 years and mean body mass index of 25 ± 4 underwent ACL reconstruction with a mean operative duration of 68 ± 23 minutes and a tourniquet time of 76 ± 23 minutes. In 84% of patients an autologous hamstring graft was used, in 14% a bone-patellar tendon-bone graft was used, and 2 patients received an allograft. Of 100 patients, 9 (incidence, 9%; 95% confidence interval, 4.2 to 16.4) showed asymptomatic proximal or distal deep vein thrombosis on CCUS, of whom 4 (incidence, 4%; 95% confidence interval, 1.1 to 9.9) were symptomatic. A nonfatal pulmonary embolus developed in 1 patient during the 8-week follow-up period. CONCLUSIONS: This study shows that the incidence of venous thromboembolism after arthroscopic ACL reconstruction is relatively high; a 9% incidence of asymptomatic proximal or distal deep vein thrombosis was found, whereas 4% of patients were symptomatic. Further research is recommended to assess the need for thromboprophylaxis in patients undergoing ACL reconstruction, especially when risk factors are present. LEVEL OF EVIDENCE: Level IV, case series.

[A woman with a swelling in the right groin]. / Een vrouw met een zwelling in de rechter lies.

A 59-year-old woman had a swelling in the right groin, 3 years after bilateral metal-on-metal total hip arthroplasty. The diagnosis 'pseudotumour' was confirmed after revision of the arthroplasty.

Dutch orthopedic blood management surveys 2002 and 2007: an increasing use of blood-saving measures.

BACKGROUND: Hip and knee arthroplasties are frequently complicated by the need for allogeneic blood transfusions. The surveys were developed to assess the use of blood-saving measures in orthopedic surgery in the Netherlands in 2002 and 2007. STUDY DESIGN AND METHODS: In 2002 and 2007, a questionnaire on blood management measures after several orthopedic procedures was sent to all Dutch orthopedic departments (110 and 96, respectively). RESULTS: The response was 79% in 2002 and 84% in 2007. The use of preoperative autologous blood donation remained virtually unchanged in 2002 versus 2007 for both hip (10.9 and 10.5%) and knee (5.7 and 8.2%) arthroplasty. In 2007, there was a substantial increase in departments using erythropoietine for hip (31.6­66.1%) as well as knee (24.0­55.5%) arthroplasty. There was an increase of the use of autologous retransfusion of intraoperatively suctioned washed blood in hip (20.3­28.4%) as well as knee arthroplasty (8.9­16.1%) over the 5-year period, but it was predominantly used in revision hip arthroplasty (54.3%). The use of postoperative autologous retransfusion of filtered drained wound blood increased dramatically in 5 years time in hip (11.5­51.0%) and knee arthroplasty (15.9­59.3%). CONCLUSION: There is an evident increase in the preoperative use of erythropoietin and the postoperative use of autologous retransfusion of drained blood among Dutch orthopedic departments. There appears to be an increasing awareness and positive attitude among Dutch orthopedic surgeons to implement perioperative blood-saving measures.

Dutch orthopedic thromboprophylaxis: a 5-year follow-up survey.

BACKGROUND AND PURPOSE: Previous surveys in the Netherlands have revealed that guidelines regarding orthopedic thromboprophylaxis were not followed and that a wide variation in protocols exists. This survey was performed to assess the current use of thromboprophylactic modalities and to compare it with the results of a previous survey. METHODS: All departments of orthopedic surgery in the Netherlands were sent a follow-up survey on venous thromboprophylaxis, and the data obtained were compared to the results of a survey performed 5 years earlier. RESULTS: All departments used pharmacological thromboprophylaxis following arthroplasties of the hip and knee. Low-molecular-weight heparin (LMWH) was used most frequently (79%) of the departments, followed by fondaparinux (13%). 5 years earlier, coumarin treatment was the predominant prophylaxis (79%). All departments prescribed pharmacological prophylaxis after femoral and tibial fractures; 78% used LMWH. Prophylaxis was continued for 6 weeks in 85% of cases. LMWH treatment was initiated on the day before surgery in 31% of cases (65% in the previous survey), perioperatively in 55%, and in the evening following surgery in 24%. In general, for daycare surgery and arthroscopies either no prophylaxis was given or a LMWH was given for 1 day. After anterior cruciate ligament reconstruction, 94% of departments prescribed some form of pharmacological prophylaxis. INTERPRETATION: The use of pharmacological prophylaxis after arthroplasty of the hip and knee and also after fracture surgery around the hip and knee is common practice in the Netherlands. In 5 years, the widely used coumarin derivates have been largely replaced with LMWH.

Low incidence of deep vein thrombosis after knee arthroscopy without thromboprophylaxis: a prospective cohort study of 335 patients.

BACKGROUND: There is little data on the risk of deep vein thrombosis after knee arthroscopy. PATIENTS AND METHODS: We performed a prospective cohort study to establish the incidence of venous thrombo-embolic (VTE) complications after knee arthroscopy in daycare, as detected by bilateral complete compression ultrasonography (CCUS) at day 14 (11-17) postoperatively. 335 patients completed bilateral extended ultrasound. No thromboprophylaxis was given. RESULTS: 19 (5.7%; 95% CI: 3.5%-8.7%) showed VTE on CCUS, of whom 2 were symptomatic. 1 patient developed a non-fatal pulmonary embolus during the 8-week follow-up period. There was no difference in immobilization characteristics between the patients who developed postoperative DVT and those who did not; nor could other risk factors be identified. INTERPRETATION: Since the incidence of VTE is low and a specific high-risk group for the development of VTE could not be identified, it seems justified to withhold routine pharmacological thromboprophylaxis after arthroscopy of the knee in a daycare setting.

Compliance of Dutch orthopedic departments with national guidelines on thromboprophylaxis. A survey of Dutch orthopedic thromboprohylaxis.

All 110 Dutch orthopedic departments were sent a survey on perioperative thromboprophylaxis protocols, and 79% responded. After hip and knee replacements, all used pharmacological thromboprophylaxis: a low-molecular weight heparin (LMWH) in 87% of departments, which was most often combined with vitamin K antagonists (VKAs). LMWH was usually started preoperatively (91%). After discharge, VKAs were mostly prescribed (79%) for at least 6 weeks, and often for 3 months. 17% of departments used LMWH for 6 weeks, whereas in only 3% no post-discharge prophylaxis was given. In day-care surgery, including arthroscopies, 58% use LMWH and in short-stay surgery 80% administer LMWH during the hospital stay. Because of lack of conclusive evidence for day-care surgery, the national guidelines cannot support pharmacological prophylaxis in this setting. In general, Dutch orthopedic departments comply poorly with the national guidelines on extended thromboprophylaxis for hip and knee replacement surgery, which recommends postoperative LMWH for 6 weeks. They are divided in the use of pharmacological prophylaxis in day-care surgery.