D. W. MURRAY, A. R. BRITTON, C. J. K. BULSTRODE. From the Nuffield Orthopaedic Centre, Oxford, England. The recommendation that patients having a total hip replacement should receive pharmacological thromboprophylaxis is based on the belief that fata
stable (greater than the control) when walking over barriers as was roll for the sit-to-stand task, indicative of ... after total hip replacement regarding the risk of a fall, especially in the elderly. Most patients ... metre cable to a computer whi
flap, following damage to the inferior branch of the superior gluteal nerve, or by failure ... flap, was used in 29 hips, and the posterior. (P) .... was undisplaced.
Marc E. Umlas. From the Centre for Total Joint Replacement, New York, USA. We report 16 cases of erythematous eruption on the skin within the flaps of the ...
Apr 29, 2013 - ing total hip replacement, and they were likely to change coital positions. The most common concern regarding sexual activity of patients was ...
impingement after THR, to assess the results of surgical ... dysplasia in five patients (five hips). .... dislocation of the hip, a superficial wound infection and five .... Meyer JD, PlÃ¶tz W, Tillmann K, Russlies M. Iliopsoas impingement after ceme
arthroplasty. After total hip replacement recurrent dislocation is a serious and ..... to incorrect positioning of prosthetic components, loosening of the trochanter.
hip replacement performed after fixation failed for femoral neck fracture. (A) (n = .... of femoral loosening discovered at review. No acetabular cups were loose.
We compared the radiographic results of secondary total hip replacements,. 99 following failed uncemented hemiarthroplasties and 21 following failed.
Anne McMurray, PhD, RN, FRCNA, Professor of Nursing,. Research Centre .... significance. This level was achieved using a Bonferroni. Correction to reduce the probability of making a Type I error when performing multiple tests. For single tests, the .
Girdlestone type of pseudarthrosis. The infection may not present for a considerable period after operation, though relatively few cases occur after one year ( ...
1 -Radiograph before operation. Figure. 2-Twelve months after operation. Figure. 3-Sinogram two years after operation. Figure. 4-After a Girdlestone operation.
Bilateral protrusio acetabuli following pelvic irradiation. J Rheumatol 1977;4:189-96. Hasselbacher P, Schumacher HR. Synovial fluid eosinophilia following.
In 1985 Galante pleaded that âorthopaedic surgeons should agree to a uniform method of evaluating and reporting the results of hip replacement surgeryâ. 1.
October 2006. Intra-articular injections of steroid into the hip are used for a variety of reasons in current .... A diagnosis of trochanteric bursitis was made and the ...
Consultant Plastic Surgeon. â« G. C. Bannister, MD,. FRCS(Orth), Professor of. Orthopaedic Surgery. North Bristol Trust. Avon Orthopaedic Centre,. Southmead Hospital, Bristol ... appearance of the scar at three months using a surgeon-rated visual an
The results of previous ... (THR), and 7â14 days for patients having major knee surgery. (TKR) (5). ... New anticoagulants after hip or knee replacement. Figure 1.
biocompatible is the titanium alloy extra low interstitial (ELI)2 Tiâ6Alâ4V; its composi- tion is 90 wt% Ti, 6 wt% Al, and 4 wt% V. The optimal properties for this material are produced by hot forging; any subsequent deformation and/or heat treat
and the types of arthroplasty performed are shown in Tables. II and ... arthroplasties performed. Number of ..... in all 12 a Girdlestone arthroplasty was performed.
Abstract: Instability after total hip arthroplasty (THA) is not a rare occurrence. Numerous factors have been associated with dislocation including surgical approach, implant design, failure to restore proper hip mechanics and soft tissue restraints,
V early osteointegration. On-growth of bone to porous coated prostheses is ... rich femoral component or with the ce- ... total hip arthroplasty in dogs (1, 2). Loo-.
Radiological analysis assessing heterotopic ossification, femoral osteolysis and femoral stem ... following total joint replacement.12 A retrospec- tive study by ...
Total hip replacement (THR) is a very common procedure undertaken in up to 285 000 .... diagnosis can include activity-related pain, aseptic loosening,.
an ideal total hip replacement with a large femoral head and a high head-neck ratio. B: Cam-type impingement in the native hip caused by a reduced femoral head-neck offset and similar impingement in a prosthetic hip with a small femoral head and a sk
Journal of Orthopaedic Surgery 2010;18(1):92-7
Review article: Thromboprophylaxis after total hip replacement Andrew P Kurmis1,2
Department of Orthopaedic Surgery, Royal Melbourne Hospital, Parkville, Victoria, Australia 2 School of Medicine, Flinders University, Bedford Park, South Australia, Australia
ABSTRACT The risk of secondary haematologic complications such as deep vein thrombosis or pulmonary embolism increases significantly when a transient period of hypercoagulability is induced after total hip replacement (THR). A number of drug-based anticoagulant approaches are available to modulate this risk, but the optimal length of therapy for such approaches remains unclear. The literature was reviewed for evidence-based support of the routine use of an extended course (>14 days) of thromboprophylaxis after THR. Electronic databases and real-time online literature searches were performed, using the PubMed (Medline), EMBASE, CINAHL and GoogleScholar, and the Cochrane and British Medical Journal Clinical Evidence libraries. Author-defined key word searches were performed. Only articles in the English language, for which full text could be retrieved, were reviewed. There is robust evidence to support an extended course (>14 days) of thromboprophylaxis after THR. Such recommendations have been translated into the guidelines of key professional bodies, including those of the American College of Chest Physicians. Meta-
review suggests a clear benefit of such regimens and supports wider adoption, even when weighed against a small increase in adverse events. Key words: anticoagulants; arthroplasty, replacement, hip; pulmonary embolism; venous thrombosis
INTRODUCTION A transient period of hypercoagulability can occur during and after major orthopaedic surgery.1,2 There is no universally accepted postulate to account for this phase of haematologic homeostatic dysregulation. A safe and efficacious anticoagulation regimen is necessary, as the demands for joint replacement surgery worldwide,3,4 the societal and patient demands for improved outcomes, and the need for evidencebased medicine-guided practices increase.5–7 Both pharmacologic and non-pharmacologic options are available for prevention of venous thromboembolic events (VTEs).8–12 The combined use of both confers synergistic utility,3,8,12–14 whereas their individual use is rare.9,15 Optimisation of standards of care in nonpharmacologic approaches has been indicated.3,16 All available pharmacological thromboprophylaxis regimens have a risk profile.3,16,17 The literature was
Address correspondence and reprint requests to: Dr Andrew P Kurmis, Department of Orthopaedic Surgery (L7 East), Royal Melbourne Hospital, Grattan Street, Parkville, Victoria, 3050, Australia. E-mail: [email protected]
Vol. 18 No. 1, April 2010
METHODS The PubMed (Medline), EMBASE, CINAHL and GoogleScholar, and the Cochrane and British Medical Journal Clinical Evidence libraries were searched using the key words: arthroplasty, total hip replacement, THR, thromboprophylaxis, and/or thrombo*.
VENOUS THROMBOEMBOLIC EVENTS THR is a commonly performed and ever-increasing orthopaedic procedure worldwide.16,18–20 Its demand is driven by refinements in implant design and surgical technique, increase in population life-expectancy, and increase in patient expectations in functional quality of life.19,21,22 Although THR can reduce pain and improve movement and function,16,20,22–25 it is an invasive procedure and has risks and complications,26 particularly postoperative formation of intravascular blood clots.16,27–32 VTEs can result in a high degree of morbidity and/or mortality related to pelvic and lower-limb deep vein thrombosis (DVT) and pulmonary embolism (PE).8,26–28,31,33–37 Without prophylaxis, VTE has an estimated incidence of 40 to 60%,3,17,38–40 and an event rate warranting medical attention of 1.6 to 6.4%.8,27,38,40,41 Stratification of the risks to identify patients most in need of vigilant monitoring or aggressive prophylactic therapy has been undertaken.8,42 Nonetheless, inconsistency in the definition of a VTE and disparity between clinical43 and subclinical44 (research) applications render comparisons between studies difficult, whereas biased statistical analysis may reflect both frank and sub-clinical VTEs.7 Using invasive diagnostic tools,37,45,46 the true prevalence of VTEs far exceeds that of patients who are symptomatic,3,10,40,47 which only serves to draw yet more attention to the induction of a hypercoagulable state after THR.48
EXTENDED COURSE OF THROMBOPROPHYLAXIS Recommendations for the duration of anti-VTE
therapy vary from 14 to 42 days,8,27,28,32,33,37,41,42,49–54 but their translation into clinical practice has been inconsistent.5,14,49,55,56 After THR, a thromboprophylactic regimen of >14 days has been advocated by many international bodies. For example the American College of Chest Physicians (ACCP) supports an extended course of prophylaxis with low-molecularweight heparin (LMWH) or warfarin for 28 to 35 days.32,39,42,56–61 Compared with placebo, LMWH has been shown to reduce overall VTE rates significantly (Fig.).32 An extended course (4–6 weeks) of prophylaxis is superior to placebo in reducing the incidence of symptomatic VTEs (1.3% vs. 3.3%, p<0.05, relative risk reduction [RRR]=61%, number needed to treat [NNT]=50) as well as asymptomatic VTEs (9.6% vs. 19.6%, p<0.05, RRR=51%, NNT=10).62 Compared with placebo, an extended course (4 weeks) of LMWH reduces the incidence of symptomatic VTEs from 4.2% to 1.4% (p<0.001, RRR=67%, NNT=36), and the overall rate from 22.5% to 7.9% (p<0.001, RRR=65%, NNT=7) [Table].5 Moreover, asymptomatic VTEs increase the risk of developing post-thrombotic syndrome (RR=2.36; 95% CI, 1.64–3.41; p<0.001).63 The negative impact of extended courses of VTE prophylaxis on outcomes (i.e. number needed to harm [NNH]) is difficult to determine, because of the low frequency of such adverse events.7,58 The rate of minor
Incidence of deep vein thrombosis (%)
reviewed to determine whether evidence-based support is sufficient to justify an extended course (>14 days) of anticoagulant prophylaxis after total hip replacement (THR). This study focused on the practical classification of VTEs and the optimal clinical ‘window’ (timeframe) for the use of anticoagulants.
Thromboprophylaxis after THR
Placebo Extended course of lowmolecular-weight heparin
p<0.001 p=0.034 p<0.001
Planes Bergqvist Dahl et al.,37 et al.,57 et al.,2 1996 1996 1997
Lassen et al.,58 1998
Hull et al.,59 2000
Comp et al.,60 2001
Figure The incidence of deep vein thrombosis after total hip arthroplasty in patients receiving an extended course of low-molecular-weight heparin versus placebo, with a mean duration being 34 (range, 30–35) days.32
Journal of Orthopaedic Surgery
Table The postoperative relative risks of symptomatic and overall venous thromboembolism5 Study
Symptomatic venous thromboembolism Low-molecular-weight heparin group No. (%)
Control group No. (%)
Overall venous thromboembolism
Relative risk p Value Low-molecu(95% CI fixed) lar-weight heparin group No. (%)
Planes et 3/90 (3.3) 7/89 (7.9) 0.42 (0.11–1.59) al.,37 1996 Bergqvist et 2/131 (1.5) 10/131 (7.6) 0.20 (0.04–0.90) al.,57 1996 Dahl et 4/117 (3.4) 6/110 (5.5) 0.63 (0.18–2.16) al.,2 1997 Lassen et 2/140 (1.4) 3/141 (2.1) 0.67 (0.11–3.96) al.,58 1998 Hull et 4/389 (1.0) 3/180 (1.7) 0.62 (0.14–2.73) al.,59 2000 Comp et 0/224 (0.0) 7/211 (3.3) 0.06 (0.00–1.09) al.,60 2001 Total 15/1091 (1.4) 36/862 (4.2) 0.36 (0.20–0.67)
bleeding after conventional anticoagulants has been quoted to be 4 to 5 times higher than with placebo,37,57 with a significant increase from 2.5 to 3.7% (RR increase=1.56; 95% CI, 1.08–2.26; NNH=83).62 Minor bleeding events include subcutaneous bruising at the injection site and non-dramatic wound ooze. The major bleeding rate is about 2.5% (95% CI, 1–3%),64 which is not significantly higher than that after placebo.5,32,58,62 Furthermore, major bleeding events occur even less frequently with longer duration of prophylaxis. The daily incidence rates were 1.8% within the first 5 days, and 0.3% after 7 days, and 0.1% at 10 days.65 The efficacy and safety of such prophylaxis increase significantly (p=0.025) beyond 10 days.66 An array of drugs are available for VTE prophylaxis,3,17 from aspirin8,9,17 to warfarin,9,13,15,16,27,28,34,50,67 unfractionated heparin,17,18,28,36,68,69 the factor Xa inhibitor fondaparinux,6,16,29,31,69 and LMWH5,9,16,28,30–32,53 (such as enoxaparin sodium).13,34,37,68,70 Several newer agents targeting novel steps in the coagulation cascade have also been studied.2,3,28,45,46,69,71 Each of these agents carries its own risk profile.35,42,68,72 Therefore, the benefit of VTE reduction must be weighed against the impact of potential adverse events,72,73 including excessive bleeding.9,13,17,67,73 In addition, in a budgetdriven health care environment, cost-per-patient considerations29,51,54,69,74 are important, especially in institutional practices.3,13,70 There is no universally accepted single thromboprophylactic agent of choice.3,16,17 Clinicians are advised to use those that they are most familiar with. An extended course (28–35 days) of enoxaparin sodium, delivered
as a daily subcutaneous injection,6,75 initiated on postoperative day one38,45,46,64 and continued for 4 weeks, is a popular choice, with reduction in DVT and PE rates being 40 to 72% and 46 to 65%, respectively.62,76–78 This agent can be administered to patients in an out-of-hospital setting (e.g. home-visit nursing services) as required, with limited need for haematologic monitoring. The efficacy and safety profile of enoxaparin has been extensively investigated.34,37,47,70,74 Recent advances in oral preparations of LMWHs have simplified its delivery (especially in out-of-hospital settings),3 but rigorous safety and efficacy appraisal is required.
LIMITATIONS The protocol for the time to mobilisation, the use of mechanical anti-thrombotic devices, and the aggressiveness of early physiotherapy vary from institution to institution, as do initiation of preoperative thromboprophylaxis64 and the length of hospital stay. All are related to the frequency of VTE events, but their absolute impact has not yet been supported by level I/II evidence.64 Additional factors limiting generalisability include specialised patient management facilities (other than the expertise/resources available in general settings), small sample size,37,48,50,75 availability of highly sophisticated VTE monitoring approaches (related to external validity),30,45 poorly selected or absent of controls,48 resorting to convenience (nonrandomised) sampling,79 retrospective data,80 poorly
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defined methodology (limiting reproducibility), and the absence of adequate blinding.
CONCLUSION There is robust evidence to support an extended course (>14 days) of thromboprophylaxis after THR, which confers a RRR of 0.33 to 0.41, even when weighed against the slight increase in adverse events.
Thromboprophylaxis after THR
Sound clinical acumen and judgement is nonetheless important. The extended regimen should provide a baseline, which can be adapted according to the specific circumstances (including clinical indication) of each patient. Clinicians are advised to use the pharmaceuticals that they are most familiar with to cover the high-risk window (postoperative days 14 to 35). The widely used LMWH (enoxaparin sodium) is convenient and reliable, and has a well-documented safety and efficacy profile.
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