The October 2024 Hip & Pelvis Roundup360 looks at: Does the primary surgical approach matter when choosing the approach for revision total hip arthroplasty?; Time to achieve the minimal clinically important difference in primary total hip arthroplasty: comparison of anterior and posterior surgical approaches; To scope or not to scope: arthroscopy as an adjunct to PAO does not provide better clinical outcomes at one year than PAO alone; Re-exploring horizons in hip resurfacing: two-year results of a ceramic-on-ceramic hip resurfacing; Association between tranexamic acid and decreased periprosthetic joint infection risk in patients undergoing total hip and knee arthroplasty; Octogenarians fare well: in revision for infection age is not a bar.
Historically, patients undergoing surgery for adolescent idiopathic scoliosis (AIS) have been nursed postoperatively in a critical care (CC) setting because of the challenges posed by prone positioning, extensive exposures, prolonged operating times, significant blood loss, major intraoperative fluid shifts, cardiopulmonary complications, and difficulty in postoperative pain management. The primary aim of this paper was to determine whether a scoring system, which uses Cobb angle, forced vital capacity (FVC), forced expiratory volume in one second (FEV1), and number of levels to be fused, is a valid method of predicting the need for postoperative critical care in AIS patients who are to undergo scoliosis correction with posterior spinal fusion (PSF). We retrospectively reviewed all AIS patients who had undergone PSF between January 2018 and January 2020 in a specialist tertiary spinal referral centre. All patients were assessed preoperatively in an anaesthetic clinic. Postoperative care was defined as ward-based (WB) or critical care (CC)Aims
Methods
The October 2023 Trauma Roundup360 looks at: Intramedullary nailing versus sliding hip screw in trochanteric fracture management: the INSITE randomized clinical trial; Five-year outcomes for patients with a displaced fracture of the distal tibia; Direct anterior versus anterolateral approach in hip joint hemiarthroplasty; Proximal humerus fractures: treat them all nonoperatively?; Tranexamic acid administration by prehospital personnel; Locked plating versus nailing for proximal tibia fractures: a multicentre randomized controlled trial; A retrospective review of the rate of septic knee arthritis after retrograde femoral nailing for traumatic femoral fractures at a single academic institution.
This edition of Cochrane Corner looks at some of the work published by the Cochrane Collaboration, covering pharmacological interventions for the prevention of bleeding in people undergoing definitive fixation or joint replacement for hip, pelvic, and long bone fractures; interventions for reducing red blood cell transfusion in adults undergoing hip fracture surgery: an overview of systematic reviews; and pharmacological treatments for low back pain in adults: an overview of Cochrane Reviews
The February 2023 Foot & Ankle Roundup360 looks at: Joint inflammatory response in ankle and pilon fractures; Tibiotalocalcaneal fusion with a custom cage; Topical application of tranexamic acid can reduce blood loss in calcaneal fractures; Risk factors for failure of total ankle arthroplasty; Pain catastrophizing: the same as pain forecasting?.
Orthopaedic surgeries are complex, frequently performed procedures associated with significant haemorrhage and perioperative blood transfusion. Given refinements in surgical techniques and changes to transfusion practices, we aim to describe contemporary transfusion practices in orthopaedic surgery in order to inform perioperative planning and blood banking requirements. We performed a retrospective cohort study of adult patients who underwent orthopaedic surgery at four Canadian hospitals between 2014 and 2016. We studied all patients admitted to hospital for nonarthroscopic joint surgeries, amputations, and fracture surgeries. For each surgery and surgical subgroup, we characterized the proportion of patients who received red blood cell (RBC) transfusion, the mean/median number of RBC units transfused, and exposure to platelets and plasma.Aims
Methods
A typical pattern of blood loss associated with total hip arthroplasty (THA) is 200 ml intraoperatively and 1.3 l in the first 48 postoperative hours. Tranexamic acid (TXA) is most commonly given as a single preoperative dose only and is often withheld from patients with a history of thromboembolic disease as they are perceived to be “high-risk” with respect to postoperative venous thromboembolism (VTE). The TRanexamic ACid for 24 hours trial (TRAC-24) aimed to identify if an additional 24-hour postoperative TXA regime could further reduce blood loss beyond a once-only dose at the time of surgery, without excluding these high-risk patients. TRAC-24 was a prospective, phase IV, single centre, open label, parallel group, randomized controlled trial (RCT) involving patients undergoing primary unilateral elective THA. The primary outcome measure was the indirect calculated blood loss (IBL) at 48 hours. The patients were randomized into three groups. Group 1 received 1 g intravenous (IV) TXA at the time of surgery and an additional oral regime for 24 hours postoperatively, group 2 only received the intraoperative dose, and group 3 did not receive any TXA.Aims
Methods
The aim of this study was to investigate the hypothesis that a single dose of tranexamic acid (TXA) would reduce blood loss and transfusion rates in elderly patients undergoing surgery for a subcapital or intertrochanteric (IT) fracture of the hip. In this single-centre, randomized controlled trial, elderly patients undergoing surgery for a hip fracture, either hemiarthroplasty for a subcapital fracture or intramedullary nailing for an IT fracture, were screened for inclusion. Patients were randomly allocated to a study group using a sealed envelope. The TXA group consisted of 77 patients, (35 with a subcapital fracture and 42 with an IT fracture), and the control group consisted of 88 patients (29 with a subcapital fracture and 59 with an IT fracture). One dose of 15 mg/kg of intravenous (IV) TXA diluted in 100 ml normal saline (NS,) or one dose of IV placebo 100 ml NS were administered before the incision was made. The haemoglobin (Hb) concentration was measured before surgery and daily until the fourth postoperative day. The primary outcomes were the total blood loss and the rate of transfusion from the time of surgery to the fourth postoperative day.Aims
Methods
Tranexamic acid (TXA) has been shown to reduce blood loss and transfusion requirements in patients undergoing orthopaedic surgery. There remains a lack of prospective evidence for the use of TXA in patients undergoing periacetabular osteotomy (PAO). The purpose of this study was to determine if intravenous (IV) TXA is effective in reducing calculated blood loss and transfusions after PAO. This was a single-centre prospective double-blind placebo-controlled randomized trial of 81 patients aged 12 to 45 years undergoing elective PAO by a single surgeon. The intervention group (n = 40) received two doses of IV TXA of a maximum 1 g in each dose; the control group (n = 41) received two doses of 50 ml 0.9% saline IV. The primary outcome was perioperative calculated blood loss. Secondary outcomes included allogenic transfusions and six-week postoperative complications.Aims
Methods
The aim of this study was to examine whether tourniquet use can improve perioperative blood loss, early function recovery, and pain after primary total knee arthroplasty (TKA) in the setting of multiple-dose intravenous tranexamic acid. This was a prospective, randomized clinical trial including 180 patients undergoing TKA with multiple doses of intravenous tranexamic acid. One group was treated with a tourniquet during the entire procedure, the second group received a tourniquet during cementing, and the third group did not receive a tourniquet. All patients received the same protocol of intravenous tranexamic acid (20 mg/kg) before skin incision, and three and six hours later (10 mg/kg). The primary outcome measure was perioperative blood loss. Secondary outcome measures were creatine kinase (CK), CRP, interleukin-6 (IL-6), visual analogue scale (VAS) pain score, limb swelling ratio, quadriceps strength, straight leg raising, range of motion (ROM), American Knee Society Score (KSS), and adverse events.Aims
Methods
Aims.
Tranexamic acid (TXA) is proven to reduce blood loss following total knee arthroplasty (TKA), but there are limited data on the impact of similar dosing regimens in revision TKA. The purpose of this multicentre randomized clinical trial was to determine the optimal regimen to maximize the blood-sparing properties of TXA in revision TKA. From six-centres, 233 revision TKAs were randomized to one of four regimens: 1 g of intravenous (IV) TXA given prior to the skin incision, a double-dose regimen of 1 g IV TXA given both prior to skin incision and at time of wound closure, a combination of 1 g IV TXA given prior to skin incision and 1 g of intraoperative topical TXA, or three doses of 1950 mg oral TXA given two hours preoperatively, six hours postoperatively, and on the morning of postoperative day one. Randomization was performed based on the type of revision procedure to ensure equivalent distribution among groups. Power analysis determined that 40 patients per group were necessary to identify a 1 g/dl difference in the reduction of haemoglobin postoperatively between groups with an alpha of 0.05 and power of 0.80. Per-protocol analysis involved regression analysis and two one-sided Aims
Patients and Methods
Tranexamic acid (TXA) has been shown to significantly reduce transfusion rates in primary total hip arthroplasties (THAs), but high-quality evidence is limited in the revision setting. The purpose of the current study was to compare the rate of blood transfusions and symptomatic venous thromboembolic events (VTEs) in a large cohort of revision THAs treated with or without intravenous (IV) TXA. We performed a retrospective review of 3264 revision THAs (2645 patients) between 2005 and 2014, of which 1142 procedures received IV TXA (1 g at incision and 1 g at closure). The mean age in the revision group with TXA was 65 years (28 to 95), with 579 female patients (51%). The mean age in the revision group treated without TXA was 67 years (21 to 98), with 1160 female patients (55%). Outcomes analyzed included rates of transfusion and symptomatic VTEs between procedures undertaken with and without TXA. These comparisons were performed for the overall cohort, as well as within cases subcategorized for aseptic or septic aetiologies. A propensity score was developed to minimize bias between groups and utilized age at revision THA, sex, body mass index, American Society of Anesthesiologists (ASA) score, preoperative anticoagulation, and year of surgery.Aims
Patients and Methods
Intra-articular injections of local anaesthetics (LA), glucocorticoids (GC), or hyaluronic acid (HA) are used to treat osteoarthritis (OA). Contrast agents (CA) are needed to prove successful intra-articular injection or aspiration, or to visualize articular structures dynamically during fluoroscopy. Tranexamic acid (TA) is used to control haemostasis and prevent excessive intra-articular bleeding. Despite their common usage, little is known about the cytotoxicity of common drugs injected into joints. Thus, the aim of our study was to investigate the effects of LA, GC, HA, CA, and TA on the viability of primary human chondrocytes and tenocytes Human chondrocytes and tenocytes were cultured in a medium with three different drug dilutions (1:2; 1:10; 1:100). The following drugs were used to investigate cytotoxicity: lidocaine hydrochloride 1%; bupivacaine 0.5%; triamcinolone acetonide; dexamethasone 21-palmitate; TA; iodine contrast media; HA; and distilled water. Normal saline served as a control. After an incubation period of 24 hours, cell numbers and morphology were assessed.Objectives
Methods
Aims. Cementless primary total hip arthroplasty (THA) is associated with risks of bleeding and thromboembolism. Anticoagulants are effective as venous thromboprophylaxis, but with an increased risk of bleeding. Tranexamic acid (TXA) is an efficient
The intra-articular administration of tranexamic acid (TXA) has
been shown to be effective in reducing blood loss in unicompartmental
knee arthroplasty and anterior cruciate reconstruction. The effects
on human articular cartilage, however, remains unknown. Our aim,
in this study, was to investigate any detrimental effect of TXA
on chondrocytes, and to establish if there was a safe dose for its
use in clinical practice. The hypothesis was that TXA would cause
a dose-dependent damage to human articular cartilage. The cellular morphology, adhesion, metabolic activity, and viability
of human chondrocytes when increasing the concentration (0 mg/ml
to 40 mg/ml) and length of exposure to TXA (0 to 12 hours) were
analyzed in a 2D model. This was then repeated, excluding cellular
adhesion, in a 3D model and confirmed in viable samples of articular cartilage.Aims
Materials and Methods
Due to the complex anatomy of the pelvis, limb-sparing resections
of pelvic tumours achieving adequate surgical margins, can often
be difficult. The advent of computer navigation has improved the
precision of resection of these lesions, though there is little
evidence comparing resection with or without the assistance of navigation. Our aim was to evaluate the efficacy of navigation-assisted surgery
for the resection of pelvic bone tumours involving the posterior
ilium and sacrum. Using our prospectively updated institutional database, we conducted
a retrospective case control study of 21 patients who underwent
resection of the posterior ilium and sacrum, for the treatment of
a primary sarcoma of bone, between 1987 and 2015. The resection
was performed with the assistance of navigation in nine patients
and without navigation in 12. We assessed the accuracy of navigation-assisted
surgery, as defined by the surgical margin and how this affects
the rate of local recurrence, the disease-free survival and the
effects on peri-and post-operative morbidity. Aims
Patients and Methods
Objectives. Tranexamic acid (TXA) is an
Tranexamic acid (TXA) has been used to reduce
blood loss during total hip arthroplasty (THA), but its use could increase
the risk of venous thromboembolic disease (VTE). Several studies
have reported that TXA does not increase the prevalence of deep
vein thrombosis (DVT), but most of those used routine chemical thromboprophylaxis,
thereby masking the potential increased risk of TXA on VTE. We wished
to ascertain whether TXA increases the prevalence of VTE in patients
undergoing THA without routine chemical thromboprophylaxis. We carried
out a retrospective case-control study in 254 patients who underwent
a primary THA, 127 of whom received TXA (1 g given pre-operatively)
and a control group of 127 who did not. All patients had mechanical
but no chemical thomboprophylaxis. Each patient was examined for
DVT by bilateral ultrasonography pre-operatively and on post-operative
days 1 and 7. TXA was found to statistically significantly increase
the incidence of total DVT on post-operative day 7 compared with
the control group (24 (18.9%) and 12 (9.4%), respectively; p <
0.05) but most cases of DVT were isolated distal DVT, with the exception
of one patient with proximal DVT in each group. One patient in the control
group developed a non-fatal symptomatic pulmonary embolism (PE).
The use of TXA did not appear to affect the prevalence of either
proximal DVT or PE. Cite this article:
The December 2014 Hip &
Pelvis Roundup360 looks at: Sports and total hips; topical tranexamic acid and blood conservation in hip replacement; blind spots and biases in hip research; no recurrence in cam lesions at two years; to drain or not to drain?; sonication and diagnosis of implant associated infection; and biomarkers and periprosthetic infection
Exsanguination is the second most common cause
of death in patients who suffer severe trauma. The management of
haemodynamically unstable high-energy pelvic injuries remains controversial,
as there are no universally accepted guidelines to direct surgeons
on the ideal use of pelvic packing or early angio-embolisation.
Additionally, the optimal resuscitation strategy, which prevents
or halts the progression of the trauma-induced coagulopathy, remains
unknown. Although early and aggressive use of blood products in
these patients appears to improve survival, over-enthusiastic resuscitative
measures may not be the safest strategy. This paper provides an overview of the classification of pelvic
injuries and the current evidence on best-practice management of
high-energy pelvic fractures, including resuscitation, transfusion
of blood components, monitoring of coagulopathy, and procedural
interventions including pre-peritoneal pelvic packing, external
fixation and angiographic embolisation. Cite this article:
Intravenous tranexamic acid (TXA) has been shown
to be effective in reducing blood loss and the need for transfusion
after joint replacement. Recently, there has been interest in applying
it topically before the closure of surgical wounds. This has the
advantages of ease of application, maximum concentration at the
site of bleeding, minimising its systemic absorption and, consequently,
concerns about possible side-effects. We conducted a systematic review and meta-analysis which included
14 randomised controlled trials (11 in knee replacement, two in
hip replacement and one in both) which investigated the effect of
topical TXA on blood loss and rates of transfusion. Topical TXA
significantly reduced the rate of blood transfusion (total knee
replacement: risk ratio (RR) 4.51; 95% confidence interval (CI):
3.02 to 6.72; p <
0.001 (nine trials, I2 = 0%); total
hip replacement: RR 2.56; 95% CI: 1.32 to 4.97, p = 0.004 (one trial)).
The rate of thromboembolic events with topical TXA were similar
to those found with a placebo. Indirect comparison of placebo-controlled
trials of topical and intravenous TXA indicates that topical administration
is superior to the intravenous route. In conclusion, topical TXA is an effective and safe method of
reducing the need for blood transfusion after total knee and hip
replacement. Further research is required to find its optimum dose
for topical use. Cite this article:
Blood loss during total knee replacement (TKR)
remains a significant concern. In this study, 114 patients underwent TKR,
and were divided into two groups based on whether they received
a new generation fibrin sealant intra-operatively, or a local infiltration
containing adrenaline. Groups were then compared for mean calculated
total blood volume (TBV) loss, transfusion rates, and knee range
of movement. Mean TBV loss was similar between groups: fibrin sealant
mean was 705 ml (281 to 1744), local adrenaline mean was 712 ml
(261 to 2308) (p = 0.929). Overall, significantly fewer units of
blood were transfused in the fibrin sealant group (seven units)
compared with the local adrenaline group (15 units) (p = 0.0479).
Per patient transfused, significantly fewer units of blood were transfused
in the fibrin sealant group (1.0 units) compared with the local
adrenaline group (1.67 units) (p = 0.027), suggesting that the fibrin
sealant may reduce the need for multiple unit transfusions. Knee
range of movement was similar between groups. From our results,
it appears that application of this newer fibrin sealant results
in blood loss and transfusion rates that are low and similar to
previously applied fibrin sealants. Cite this article:
To review the current best surgical practice and detail a multi-disciplinary
approach that could further reduce joint replacement infection. Review of relevant literature indexed in PubMed.Objectives
Methods
Despite advances in contemporary hip and knee
arthroplasty, blood loss continues to be an issue. Though blood transfusion
has long been used to treat post-operative anemia, the associated
risks are well established. The objective of this article is to
present two practical and effective approaches to minimising blood
loss and transfusion rates in hip and knee arthroplasty: the use
of
The October 2012 Hip &
Pelvis Roundup360 looks at: diagnosing the infected hip replacement; whether tranexamic acid has a low complication rate; the relationship between poor cementing technique and early failure of resurfacing; debridement and retention for the infected replacement; triple-tapered stems and bone mineral density; how early discharge can be bad for your sleep; an updated QFracture algorithm to predict the risk of an osteoporotic fracture; and local infiltration analgesia and total hip replacement.
Tranexamic acid (TEA), an inhibitor of fibrinolysis,
reduces blood loss after routine total knee replacement (TKR). However,
controversy persists regarding the dosage and timing of administration
of this drug during surgery. We performed a prospective randomised
controlled study to examine the optimum blood-saving effect of TEA
in minimally invasive TKR. We randomly assigned 151 patients who underwent unilateral minimally
invasive TKR to three groups: 1) a placebo group (50 patients);
2) a one-dose TEA group (52 patients), who received one injection
of TEA (10 mg/kg) intra-operatively on deflation of the tourniquet;
and 3) a two-dose TEA group (49 patients), who received two injections
of TEA (10 mg/kg) given pre-operatively and intra-operatively. Total
blood loss was calculated from the maximum loss of haemoglobin.
All patients were followed clinically for the presence of venous
thromboembolism (VTE). The mean total blood loss was significantly higher in the placebo
group than in the other two groups (1222 ml (845 to 2043) Our prospective randomised controlled study showed that one intra-operative
injection of TEA is effective for blood conservation after minimally
invasive TKR.
There have been many advances in the resuscitation
and early management of patients with severe injuries during the
last decade. These have come about as a result of the reorganisation
of civilian trauma services in countries such as Germany, Australia
and the United States, where the development of trauma systems has
allowed a concentration of expertise and research. The continuing
conflicts in the Middle East have also generated a significant increase
in expertise in the management of severe injuries, and soldiers
now survive injuries that would have been fatal in previous wars.
This military experience is being translated into civilian practice. The aim of this paper is to give orthopaedic surgeons a practical,
evidence-based guide to the current management of patients with
severe, multiple injuries. It must be emphasised that this depends
upon the expertise, experience and facilities available within the
local health-care system, and that the proposed guidelines will
inevitably have to be adapted to suit the local resources.
We conducted a systematic review and meta-analysis
of randomised controlled trials evaluating the effect of tranexamic
acid (TXA) upon blood loss and transfusion in primary total knee
replacement. The review used the generic evaluation tool designed
by the Cochrane Bone, Joint and Muscle Trauma Group. A total of
19 trials were eligible: 18 used intravenous administration, one
also evaluated oral dosing and one trial evaluated topical use.
TXA led to a significant reduction in the proportion of patients
requiring blood transfusion (risk ratio (RR) 2.56, 95% confidence
interval (CI) 2.1 to 3.1, p <
0.001; heterogeneity I2 =
75%; 14 trials, 824 patients). Using TXA also reduced total blood
loss by a mean of 591 ml (95% CI 536 to 647, p <
0.001; I2 =
78%; nine trials, 763 patients). The clinical interpretation of
these findings is limited by substantial heterogeneity. However,
subgroup analysis of high-dose (>
4 g) TXA showed a plausible consistent
reduction in blood transfusion requirements (RR 5.33; 95% CI 2.44
to 11.65, p <
0.001; I2 = 0%), a finding that should
be confirmed by a further well-designed trial. The current evidence
from trials does not support an increased risk of deep-vein thrombosis
(13 trials, 801 patients) or pulmonary embolism (18 trials, 971
patients) due to TXA administration.
We report a systematic review and meta-analysis of published randomised controlled trials evaluating the efficacy of tranexamic acid (TXA) in reducing blood loss and transfusion in total hip replacement (THR). The data were evaluated using the generic evaluation tool designed by the Cochrane Bone, Joint and Muscle Trauma Group. We identified 11 clinical trials which were suitable for detailed extraction of data. There were no trials that used TXA in revision THR. A total of seven studies (comprising 350 patients) were eligible for the blood loss outcome data. The use of TXA reduced intra-operative blood loss by a mean of 104 ml (95% confidence interval (CI) −164 to −44, p = 0.0006, heterogeneity I2 0%), postoperative blood loss by a mean of 172 ml (95% CI −263 to −81, p = 0.0002, heterogeneity I2 63%) and total blood loss by a mean of 289 ml (95% CI −440 to −138, p <
0.0002, heterogeneity I2 54%). TXA led to a significant reduction in the proportion of patients requiring allogeneic blood transfusion (risk difference −0.20, 95% CI −0.29 to −0.11, p <
0.00001, I2 15%). There were no significant differences in deep-vein thrombosis, pulmonary embolism, infection rates or other complications among the study groups.
Fibrin glue, also known as fibrin sealant, is now established as a haemostatic agent in surgery, but its role in orthopaedic surgery is neither well known nor clearly defined. Although it was originally used over 100 years ago, concerns about transmission of disease meant that it fell from favour. It is also available as a slow-release drug delivery system and as a substrate for cellular growth and tissue engineering. Consequently, it has the potential to be used in a number of ways in orthopaedic surgery. The purpose of this review is to address its use in surgery of the knee in which it appears to offer great promise.
Antiplatelet agents are widely prescribed for the primary and secondary prevention of cardiovascular events. A common clinical problem facing orthopaedic and trauma surgeons is how to manage patients receiving these agents who require surgery, either electively or following trauma. The dilemma is to balance the risk of increased blood loss if the antiplatelet agents are continued peri-operatively against the risk of coronary artery/stent thrombosis and/or other vascular event if the drugs are stopped. The traditional approach of stopping these medications up to two weeks before surgery appears to pose significant danger to patients and may require review. This paper covers the important aspects regarding the two most commonly prescribed antiplatelet agents, aspirin and clopidogrel.
Tranexamic acid is a fibrinolytic inhibitor which reduces blood loss in total knee replacement. We examined the effect on blood loss of a standardised intravenous bolus dose of 1 g of tranexamic acid, given at the induction of anaesthesia in patients undergoing total hip replacement and tested the potential prothrombotic effect by undertaking routine venography. In all, 36 patients received 1 g of tranexamic acid, and 37 no tranexamic acid. Blood loss was measured directly per-operatively and indirectly post-operatively. Tranexamic acid reduced the early post-operative blood loss and total blood loss (p = 0.03 and p = 0.008, respectively) but not the intraoperative blood loss. The tranexamic acid group required fewer transfusions (p = 0.03) and had no increased incidence of deep-vein thrombosis. The reduction in early post-operative blood loss was more marked in women (p = 0.05), in whom this effect was dose-related (r = −0.793). Our study showed that the administration of a standardised pre-operative bolus of 1 g of tranexamic acid was cost-effective in reducing the blood loss and transfusion requirements after total hip replacement, especially in women.
We studied 70 consecutive patients with adolescent idiopathic scoliosis who underwent corrective surgery. They were divided into two groups. In the study group of 38 patients one or more modern blood-conservation measures was used peri-operatively. The 32 patients in the control group did not have these measures. Both groups were similar in regard to age, body-weight, the number of levels fused and the type of surgery. Only two patients in the study group were transfused with homologous blood and these transfusions were ‘off-protocol’. Wastage of autologous pre-donated units was minimal (6 of 83 units). By contrast, all patients in the control group were transfused with homologous blood. In the study group there was a significant decrease (p = 0.005) in the estimated blood loss when all the blood-conservation methods were used. The use of blood-conservation measures, the lowering of the haemoglobin trigger for transfusion and the education of the entire team involved in the care of the patient can prevent the need for homologous blood transfusion in patients undergoing surgery for adolescent idiopathic scoliosis.
We carried out a prospective randomised study to evaluate the blood loss in 60 patients having a total knee arthroplasty and divided randomly into two equal groups, one having a computer-assisted procedure and the other a standard operation. The surgery was carried out by a single surgeon at one institution using a uniform approach. The only variable in the groups was the use of intramedullary femoral and tibial alignment jigs in the standard group and single tracker pins of the imageless navigation system in the tibia and femur in the navigated group. The mean drainage of blood was 1351 ml (715 to 2890; 95% confidence interval (CI) 1183 to 1518) in the computer-aided group and 1747 ml (1100 to 3030; CI 1581 to 1912) in the conventional group. This difference was statistically significant (p = 0.001). The mean calculated loss of haemoglobin was 36 g/dl in the navigated group There was a highly significant reduction in blood drainage and the calculated Hb loss between the computer-assisted and the conventional techniques. This allows the ordering of less blood before the operation, reduces risks at transfusion and gives financial saving. Computer-assisted surgery may also be useful for patients in whom blood products are not acceptable.