Abstract. Background. The use of tourniquet in knee arthroplasty is common but in recent times, it has initiated a debate on its use. Complications from use of tourniquet are well documented in literature but there is less evidence on thigh pain, blood loss and length of stay post arthroplasty. Methods. We included 62 patients undergoing knee arthroplasty either Unicondylar knee arthroplasty or total knee arthroplasty. Patients were allocated randomly in tourniquet and without tourniquet groups. Half of the patients had UKA and other half TKA. Thigh pain was recorded using Visual analogue scale on day 1, 2 and on discharge. A drop in pre-operative and post operative haemoglobin level was recorded too. Independent sample t-test was done to compare the difference between the 2 groups mainly, drop in haemoglobin, thigh pain, knee pain and length of stay. Results. The mean drop in haemoglobin was comparable and was not statistically significant. Thigh pain on day 1 in no tourniquet group had a mean value of 0 and statistically significant difference in thigh pain at day 1,2 and discharge. In subgroup analysis between TKA and UKA the latter had improved results. Conclusions. Knee arthroplasty surgery without the use of tourniquet provides less thigh pain in the post-operative period and there isn't any significant difference in post op haemoglobin drop. None of the patient required any blood transfusion. A trend of early discharge was noted too but probably due to sample size, it wasn't statistically significant

Aims. Many surgeons choose to perform total knee arthroplasty (TKA) surgery with the aid of a tourniquet. A tourniquet is a device that fits around the leg and restricts blood flow to the limb. There is a need to understand whether tourniquets are safe, and if they benefit, or harm, patients. The aim of this study was to determine the benefits and harms of tourniquet use in TKA surgery. Methods. We searched MEDLINE, EMBASE, Cochrane Central Register of Controlled trials, and trial registries up to 26 March 2020. We included randomized controlled trials (RCTs), comparing TKA with a tourniquet versus without a tourniquet. Outcomes included: pain, function, serious adverse events (SAEs), blood loss, implant stability, duration of surgery, and length of hospital stay. Results. We included 41 RCTs with 2,819 participants. SAEs were significantly more common in the tourniquet group (53/901 vs 26/898, tourniquet vs no tourniquet respectively) (risk ratio 1.73 (95% confidence interval (CI) 1.10 to 2.73). The mean pain score on the first postoperative day was 1.25 points higher (95% CI 0.32 to 2.19) in the tourniquet group. Overall blood loss did not differ between groups (mean difference 8.61 ml; 95% CI -83.76 to 100.97). The mean length of hospital stay was 0.34 days longer in the group that had surgery with a tourniquet (95% CI 0.03 to 0.64) and the mean duration of surgery was 3.7 minutes shorter (95% CI -5.53 to -1.87). Conclusion. TKA with a tourniquet is associated with an increased risk of SAEs, pain, and a marginally longer hospital stay. The only finding in favour of tourniquet use was a shorter time in theatre. The results make it difficult to justify the routine use of a tourniquet in TKA surgery. Cite this article: Bone Joint J 2021;103-B(5):830–839

During total knee arthroplasty (TKA), a tourniquet is often used intraoperatively. There are proposed benefits of tourniquet use including shorter duration of surgery, improved surgical field visualization and increased cement penetration which may improve implant longevity. However, there are also cited side effects that include increased post-operative pain, slowed recovery, skin bruising, neurovascular injury and quadriceps weakness. Randomized controlled trials have demonstrated no differences in implant longevity, however they are limited by short follow-up and small sample sizes. The objective of the current study was to evaluate the rates of revision surgery among patients undergoing cemented TKA with or without an intraoperative tourniquet and to understand the causes and risk factors for failure. A retrospective cohort study was undertaken of all patients who received a primary, cemented TKA at a high-volume arthroplasty centre from January 1999 to December 2010. Patients who underwent surgery without the use of a tourniquet and those who had a tourniquet inflated for the entirety of the case were included. The causes and timing of revision surgery were recorded and cross referenced with the Canadian Institute of Health Information Discharge Abstract Database to reduce the loss to follow-up. Survivorship analysis was performed with the use of Kaplan-Meier curves to determine overall survival rates at final follow-up. A Cox proportional hazards model was utilized to evaluate independent predictors of revision surgery. Data from 3939 cases of primary cemented TKA were available for analysis. There were 2276 (58%) cases in which a tourniquet was used for the duration of the surgery and 1663 (42%) cases in which a tourniquet was not utilized. Mean time from the primary TKA was 14.7 years (range 0 days - 22.8 years) when censored by death or revision surgery. There were 150 recorded revisions in the entire cohort, with periprosthetic joint infection (n=50) and aseptic loosening (n=41) being the most common causes for revision. The cumulative survival at final follow-up for the tourniquetless group was 93.8% at final follow-up while the cumulative survival at final follow-up for the tourniquet group was 96.9% at final follow-up. Tourniquetless surgery was an independent predictor for all-cause revision with an HR of 1.53 (95% CI 1.1, 2.1, p=0.011). Younger age and male sex were also independent factors for all cause revision. The results of the current study demonstrate higher all-cause revision rates with tourniquetless surgery in a large cohort of patients undergoing primary cemented TKA. The available literature consists of short-term trials and registry data, which have inherent limitations. Potential causes for increased revision rates in the tourniquetless group include reduced cement penetration, increased intraoperative blood loss and longer surgical. The results of the current study should be taken into consideration, alongside the known risks and benefits of tourniquet use, when considering intraoperative tourniquet use in cemented TKA

Aims. Tourniquets have potential adverse effects including postoperative thigh pain, likely caused by their ischaemic and possible compressive effects. The aims of this preliminary study were to determine if it is possible to directly measure intramuscular pH in human subjects over time, and to measure the intramuscular pH changes resulting from tourniquet ischaemia in patients undergoing knee arthroscopy. Methods. For patients undergoing short knee arthroscopic procedures, a sterile calibrated pH probe was inserted into the anterior fascial compartment of the leg after skin preparation, but before tourniquet inflation. The limb was elevated for three minutes prior to tourniquet inflation to 250 mmHg or 300 mmHg. Intramuscular pH was recorded at one-second intervals throughout the procedure and for 20 minutes following tourniquet deflation. Probe-related adverse events were recorded. Results. A total of 27 patients were recruited to the study. Mean tourniquet time was 21 minutes (10 to 56). Tourniquet pressure was 300 mmHg for 21 patients and 250 mmHg for six patients. Mean muscle pH prior to tourniquet inflation was 6.80. Muscle pH decreased upon tourniquet inflation, with a steeper fall in the first ten minutes than for the rest of the procedure. Change in muscle pH was significant after five minutes of tourniquet ischaemia (p < 0.001). Mean muscle pH prior to tourniquet release was 6.58 and recovered to 6.75 within 20 minutes following release. No probe related adverse events were recorded. Conclusion. It is possible to directly measure skeletal muscle pH in human subjects over time. Tourniquet ischaemia results in a decrease in human skeletal muscle pH over time during short procedures. Cite this article: Bone Joint Res 2021;10(6):363–369

Tourniquet use in total knee arthroplasty (TKA) remains a subject of considerable debate. A recent study questioned the need for tourniquets based on associated risks. However, the study omitted analysis of crucial tourniquet-related parameters which have been demonstrated in numerous studies to be associated with safe tourniquet use and reduction of adverse events. The current utilization and preferences of tourniquet use in Canada remain unknown. Our primary aim was to determine the current practices, patterns of use, and opinions of tourniquet use in TKA among members of the Canadian Arthroplasty Society (CAS). Additionally, we sought to determine the need for updated best practice guidelines to inform optimal tourniquet use and to identify areas requiring further research. A self-administered survey was emailed to members of the CAS in October 2021(six-week period). The response rate was 57% (91/161). Skip logic branching was used to administer a maximum of 59 questions related to tourniquet use, beliefs, and practices. All respondents were staff surgeons and 88% were arthroplasty fellowship trained. Sixty-five percent have been in practice for ≥11 years and only 16% for 50 TKA/year, 59% have an academic practice, and >67% prefer cemented TKA. Sixty-six percent currently use tourniquets, 25% no longer do but previously did, and 9% never used tourniquets. For those not using tourniquets, the most common reasons are potential harm/risks and publications/conferences. Among current users, 48% use in all cases and an additional 37% use in 76-99% of cases. The top reason for use was improved visualization/bloodless field (88%), followed by performing a cemented TKA, used in training, and faster operative times. The main patient factor influencing selective tourniquet use was peripheral vascular disease and main surgical factors were operative duration and cementless TKA. The most frequent adverse events reported were bruising/pinching under the tourniquet and short-term pain, which majority believed were related to improper tourniquet use (prolonged time, high-pressures, poor cuff fit), yet only 8% use contoured tourniquets and 32% don't use limb protection. Despite substantial evidence in literature that tourniquet safety and probability of harm are affected by tourniquet time and pressure, only 83% and 72% of respondents believe reducing tourniquet time and pressure respectively reduce the probability of harm. In addition, no surgeon utilizes personalized limb occlusion pressure which has been demonstrated to substantially reduce tourniquet pressure while being safe and effective. Furthermore, 62% always use fixed pressure and 37% will modify the pressure based on patient parameters, most often systolic blood pressure and limb size. Almost all (88%) were interested in new evidence-based guidelines regarding these parameters. Tourniquet use in TKA remains prevalent among arthroplasty surgeons in the CAS; however tremendous practice variability regarding several key parameters required for optimal use exists. Current best practices of tourniquet use regarding personalized pressures, time, and type are not being utilized across Canada. There is considerable interest and need for further research and updated guidelines regarding key parameters of safe tourniquet usage to optimize tourniquet use in TKA

In modern orthopaedics surgery, the pneumatic tourniquet has become an essential tool that paved the way to many of the advances in trauma and orthopaedic surgery. Tourniquet slippage is one of the challenging disadvantages of it use. This study examines the possibility of reducing tourniquet slippage by comparing two different tourniquet application techniques. Twenty two patients were included in the study. Thirteen were males and eight were females. The average age was fifty five years. The patients were randomized into two groups, a controlled, and a modified tourniquet application technique groups. There were eleven patients in the control group and ten in the modified group. A standard tourniquet application technique was used as a control by applying Softband (Orthoband) alone to skin prior to application of tourniquet; this was compared to a modified version where a drape (Steridrape) was used as an interval layer. There was a strong statistical significant difference in tourniquet slippage between the two groups, p< 0.0001 the control group being the better performer. We concluded that steridrape interval makes tourniquet slippage more likely to occur

Aim. Tourniquet is widely used in extremity surgery. In order to prevent surgical site infection, correct timing of antimicrobial prophylaxis and tourniquet inflation is important. We aimed to evaluate the time for which the free drug concentration of cefuroxime is maintained above the minimal inhibitory concentration (T>MIC) in subcutaneous tissue and calcaneal cancellous bone during three clinically relevant tourniquet application scenarios. Method. Twenty-four female pigs were included. Microdialysis catheters were placed for sampling of cefuroxime concentrations bilaterally in calcaneal cancellous bone and subcutaneous tissue, and a tourniquet cuff was applied on a randomly picked leg of each pig. Subsequently, the pigs were randomized into three groups to receive 1.5 g of cefuroxime by intravenous injection 15 min prior to tourniquet inflation (Group A), 45 min prior to tourniquet inflation (Group B), and at the tourniquet release (Group C). The tourniquet duration was 90 min in all groups. Dialysates and venous blood samples were collected eight-hours postcefuroxime administration. Results. Cefuroxime concentrations were maintained above the clinical breakpoint MIC for Staphylococcus aureus (4 µg/mL) in calcaneal cancellous bone and subcutaneous tissue throughout the 90 min tourniquet duration in Group A and B. Cefuroxime administration at tourniquet release (Group C) resulted in concentrations above 4 µg/mL for a minimum of 3.5 hours in the tissues on the tourniquet side. There were no significant differences in the T>MIC (4 µg/mL) in subcutaneous tissue or calcaneal cancellous bone between the three groups. However, Group A tended toward shorter T>MIC in tourniquet calcaneal cancellous bone compared to Group C (p=0.08). Conclusions. Administration of cefuroxime (1.5 g) in the 15–45 min window prior to tourniquet inflation resulted in sufficient calcaneal cancellous bone and subcutaneous tissue concentrations throughout the 90 min tourniquet application. If the target is to maintain postoperative cefuroxime concentrations above relevant MIC values, our results suggest that a second dose of cefuroxime should be administered at tourniquet release

Aims. 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. Methods. 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. Results. The mean total blood loss was lowest in the no-tourniquet group at 867.32 ml (SD 201.11), increased in the limited-tourniquet group at 1024.35 ml (SD 176.35), and was highest in the tourniquet group at 1,213.00 ml (SD 211.48). The hidden blood loss was lowest in the no-tourniquet group (both p < 0.001). There was less mean intraoperative blood loss in the tourniquet group (77.48 ml (SD 24.82)) than in the limited-tourniquet group (137.04 ml (SD 26.96)) and the no-tourniquet group (212.99 ml (SD 56.35); both p < 0.001). Patients in the tourniquet group showed significantly higher levels of muscle damage and inflammation biomarkers such as CK, CRP, and IL-6 than the other two groups (p < 0.05). Outcomes for VAS pain scores, limb swelling ratio, quadriceps strength, straight leg raising, ROM, and KSS were significantly better in the no-tourniquet group at three weeks postoperatively (p < 0.05), but there were no significant differences at three months. No significant differences were observed among the three groups with respect to transfusion rate, thrombotic events, or the length of hospital stay. Conclusion. Patients who underwent TKA with multiple doses of intravenous tranexamic acid but without a tourniquet presented lower total blood loss and hidden blood loss, and they showed less postoperative inflammation reaction, less muscle damage, lower VAS pain score, and better early knee function. Our results argue for not using a tourniquet during TKA. Cite this article: Bone Joint Res 2020;9(6):322–332

Tourniquet is widely used in extremity surgery. In order to prevent surgical site infection, correct timing of antimicrobial prophylaxis and tourniquet inflation is important. We aimed to evaluate the time for which the free drug concentration of cefuroxime is maintained above the minimal inhibitory concentration (T>MIC) in subcutaneous tissue and calcaneal cancellous bone during three clinically relevant tourniquet application scenarios. Twenty-four female pigs were included. Microdialysis catheters were placed for sampling of cefuroxime concentrations bilaterally in calcaneal cancellous bone and subcutaneous tissue, and a tourniquet cuff was applied on a randomly picked leg of each pig. Subsequently, the pigs were randomized into three groups to receive 1.5 g of cefuroxime by intravenous injection 15 min prior to tourniquet inflation (Group A), 45 min prior to tourniquet inflation (Group B), and at the tourniquet release (Group C). The tourniquet duration was 90 min in all groups. Dialysates and venous blood samples were collected eight-hours postcefuroxime administration. Cefuroxime concentrations were maintained above the clinical breakpoint MIC for Staphylococcus aureus (4 μg/mL) in calcaneal cancellous bone and subcutaneous tissue throughout the 90 min tourniquet duration in Group A and B. Cefuroxime administration at tourniquet release (Group C) resulted in concentrations above 4 μg/mL for a minimum of 3.5 hours in the tissues on the tourniquet side. There were no significant differences in the T>MIC (4 μg/mL) in subcutaneous tissue or calcaneal cancellous bone between the three groups. However, Group A tended toward shorter T>MIC in tourniquet calcaneal cancellous bone compared to Group C (p=0.08). We conclude that administration of cefuroxime (1.5 g) in the 15–45 min window prior to tourniquet inflation resulted in sufficient calcaneal cancellous bone and subcutaneous tissue concentrations throughout the 90 min tourniquet application. If the target is to maintain postoperative cefuroxime concentrations above relevant MIC values, our results suggest that a second dose of cefuroxime should be administered at tourniquet release

Blood management protocols attempt to reduce blood loss by strategies including autologous blood donation, red cell salvage, normovolaemic haemodilution and haemostatic agents such as tranexamic acid (TXA). TXA usage in particular has become increasingly commonplace with numerous studies demonstrating a significant reduction in peri-operative blood loss and proportion of patients requiring transfusion, without increasing the risk of venous thromboembolism. Tourniquet usage has now become ubiquitous in TKA operations with reported benefits of improved visualization, shorter operative time and decreased intra-operative bleeding. However, its use is not without considerable complications including wounding dehiscence, increased venous thromboembolism, superficial wound infection and skin blistering. It is therefore imperative that we review tourniquet usage in light of ever evolving blood management strategies. The aim of this study was to evaluate the effect of stopping tourniquet usage in primary TKRs, performed by an experienced surgeon, in light of new blood reduction measures, such as a TXA. A retrospective analysis identified a total of 31 patients who underwent primary TKR without the use of a tourniquet from January 2018 to March 2019. This was compared to an earlier group of patients from the same surgeon undergoing TKR with the use of a tourniquet; dating from July 2016 to November 2017. All surgeries were performed within the same hospital (CXH). Peri-operative factors and outcome measures were collected for analysis. There was no significant difference in post-operative haemoglobin drop (Tourniquet, 23.1 g/L; No Tourniquet, 24.4 g/: p=0.604) and fall in haematocrit (Tourniquet, 0.082; No Tourniquet, 0.087: p=0.604). Allogenic blood transfusion rates were the same in both groups at 12.9% (2 patients) and blood loss was not found to be significantly different (Tourniquet, 1067ml; No tourniquet, 1058mls). No significant difference was found in operative time (Tourniquet, 103 minutes; No Tourniquet, 111.7 minutes: p=0.152) or length of stay (Tourniquet, 5.5 days; No Tourniquet, 5.2 days: p=0.516). Tranexamic acid usage was not found to be significant (p=1.000). ROM of motion and analgesia requirement was significantly better in the no tourniquet group on one post-operative day out of five analysed (p=0.025, p=00.011). No post-operative thromboembolic events were reported in either group. There was no significant difference in readmission rates (p=0.492) or complications (p=0.238). The increase in minor complications and potential increased VTE risk with tourniquet usage must be balanced against an improved visual field and reduced blood loss in TKR patients. Our study found no difference in post-operative blood loss and transfusion rates between tourniquet and no tourniquet groups. With ever evolving and improving blood loss management strategies, including the use of TXA, the application of tourniquet may not be needed. Further prospective RCTs are needed to assess the impact of tourniquet usage in light of this

Tourniquet is a commonly used tool in orthopaedic practice. Incidence of complications is low but if any develops, it is devastating. Transient nerve damage, ischemia or skin burns are the possible tourniquet related complications. There is big variation in practice regarding the limb occlusion pressure. 51 procedures in 50 patients were reviewed retrospectively in our district general hospital. We looked at quality of documentation guided by the BOAST standard (The Safe Use of Intraoperative Tourniquets, published in October 2021). Limb occlusion pressure and ischemic time were analysed. Intra-operative and post-operative notes were reviewed to assess quality of documentation and post-operative complications. Although limb occlusion pressure was above the recommended range in more than 75% of cases, there were no significant complications observed. Two cases only developed transient neuropraxia in common peroneal nerve and median nerve following tibial plateau ORIF and trapeziectomy simultaneously. Tibial ORIF fixation case had prolonged ischemic time (more than 120 minutes) and the limb occlusion pressure for the hand case was above the recommended range. Both have recovered within few days with no long-term consequences. Minimum documentation threshold was not met with regarding tourniquet site condition, method of skin isolation and padding, and exsanguination method. This relatively new standard with no previous similar guidance needs time until it is followed by the health care professionals especially when there is no high incidence of complications related to the use of the tourniquet. However, it is crucial to increase the theatre staff awareness of such standards. This will prevent devastating complications specifically in vulnerable patients. Adjustments to theatre checklist have been suggested to improved documentation. Additionally, local teaching sessions will be delivered to theatre personnel aiming at improving our compliance to this standard

Patients were randomized between surgeon chosen pressure (control) and an automatically determined tourniquet pressure(study) group. Of the study group 94/106 (88.7%) had good to excellent fields compared to the control group where 100/132 (75.8%) had good to excellent fields (p< 0.05). In the study group, 5% failed to obtain an automatic pressure. Of the remainder, the average tourniquet pressure was 198 +/− 20.2 mHg compared to 259.6 +/− 4.4 mmHg for the control group (p< 0.0001). The automatic measurement of limb occlusion pressure resulted in better operative fields at a lower pressure. To compare the quality of the operative field that results from using an automatic limb occlusion pressure measurement (study group) versus the tourniquet cuff pressure chosen by the surgeon (control group). A module allowing rapid determination of tourniquet pressure from limb occlusion pressure was attached to a Zimmer ATS tourniquet machine. Using a coin toss, patients were randomized to the study or control groups. All patients underwent elective foot and ankle operations using a wide contoured tourniquet cuff. Of two hundred and forty-three patients, one hundred and twelve were assigned to the study (automatic) group and one hundred and thirty-two to the control (surgeon selected) group. Six patients (5.4%) failed to obtain a limb occlusion pressure measurement due to anatomical constraints (toe or thigh shape) or equipment problems, leaving one hundred and six in the study group. The average measurement time to determine limb occlusion pressure was 20 +/− 6 seconds. The mean tourniquet pressure for the study group was 198.5 +/−20.2 mmHg, and 259.6 +/−4.4 mmHg for the control group (p< 0.0001). Of the study group 94 (88.7%) had good to excellent fields compared to the control group where one hundred (75.8%) had good to excellent fields (p< 0.05). An automatically determined tourniquet pressure reduced the tourniquet pressure and improved the incidence of good to excellent operative fields compared to surgeon chosen pressures. The distribution curve of automatically determined tourniquet pressure indicates that 16% of patients will have a failed field if a standard pre-selected pressure of 250 mmHg is always chosen, in part explaining why pre-selected pressure may cause a poorer operative field

A tourniquet is usually used during ankle arthroscopy to allow for improved visibility and reduced operation time. However, clinical studies on knee arthroscopy have not demonstrated this to be true. In addition, Zengerink and van Dijk emphasized a limited tourniquet time in ankle arthroscopy as a possible factor to lower the complication rate even more. The purpose of this prospective randomized controlled trial was to examine the effect of tourniquet use on arthroscopic visualization, operative time, postoperative intra-articular bleeding, postoperative pain scores and outcome of anterior ankle arthroscopy. A consecutive series of 50 patients who were scheduled for anterior ankle arthroscopy were randomized to have the surgery done either without the tourniquet inflated (25 patients) or with the tourniquet inflated (25 patients). The patients were evaluated by the course of the surgery, postoperative intra-articular bleeding, pain during the early postoperative period and by using the subjective and objective functional scores to evaluate the condition of the ankle before and 3 and 6 months after the surgery. The statistical analysis was performed with the normality of distribution tested by both Kolmogorov-Smirnov and Shapiro-Wilk tests. Appropriate parametric or non-parametric methods were then used to test statistical hypotheses, while the statistical significance (alpha, Type I error) was set at .05. Fourty-nine patients were present at the final follow-up, 6 months after the surgery. The results between the groups were comparable regarding the duration of the operative procedure, consumption of sterile saline, visualisation and functional scores. Notable difference between the groups in favour of the non-tourniquet group was present regarding postoperative bleeding, but was not statistically significant. Statistically significant difference in favour of the non-tourniquet group was found regarding postoperative pain during several days in the early postoperative period. Our study has shown that anterior ankle arthroscopy may be performed adequately without the use of a tourniquet and that it has the same operative course as in cases in which the tourniquet is used and functional outcomes which are not worse than in cases in which the tourniquet is used

Tourniquet use in total knee arthroplasty (TKA) is convenient for the surgeon and provides a bloodless field for expeditious surgery and a dry field for cementation, but can best be described as an orthopaedic tradition. It is logical for complex anatomy of ligament, nerve, and vessel surgery but it may not be necessary for TKA. In one recent randomised trial, the absence of the tourniquet was not found to affect the quality of cement fixation. There are numerous potential downsides to the use of a tourniquet including decrease range of motion, delayed recovery, increased pain, wound complications, micro-emboli, neuropathy, and increased VTE. There are also a number of complications associated with the use of a tourniquet including arterial thrombosis, skin irritation below the tourniquet, post-operative hyperemia, blood loss, less accurate intra-operative assessment, and it complicates intravenous drug administration. Studies of range of motion have shown that when there is a difference noted, the range of motion is consistently better without tourniquet use. When a tourniquet is utilised it has been found to be advantageous to only use the tourniquet for a minimal amount of the case, typically when cementing is performed. Functional strength has also been found to be improved without the use of a tourniquet. In a recent randomised trial, tourniquet use was associated with decreased quad strength at 3 weeks that persisted at 3 months. This was attributed to muscle damage, tourniquet-induced ischemia, and compressive injury. Increased peri-operative pain has also been reported in randomised trials associated with the use of a tourniquet. Edema, swelling, and limb girth issues have also been noted to be associated with tourniquet use. Exsanguinating a limb will result in swelling approximately 10% of the original volume half due to a return of blood, and half due to reactive hyperemia. Longer tourniquet times are also associated with increased wound drainage and more wound hypoxia as measured by transcutaneous oxygen levels. Tourniquet use has also been associated with embolic phenomenon with several times greater risk of large emboli. In one study where quantitative MRI was utilised on both thighs after unilateral total knee replacement with and without a tourniquet, the tourniquet group showed more atrophy with a loss of 20% of the volume compared to the normal side in total knees performed with a tourniquet which also performed clinically worse. There is a small but substantial risk of arterial thrombosis particularly in patients that have atherosclerotic plaque. Ironically there is a risk of increased post-operative blood loss due to the post-tourniquet “blush” as the blood pressure and pain increase hours after a surgical procedure is completed. There is also difficulty in identifying and coagulating posterior and lateral geniculate vessels with the components in place. Utilizing a tourniquet also interferes with intra-operative assessment of patella tracking, range of motion, ligament stability, and gap balancing. Randomised clinical trials have concluded that there is less pain and quicker recovery without the use of a tourniquet. There have also been reports of less swelling, increased range of motion, less analgesic use and better clinical outcome when a tourniquet is not utilised. A meta-analysis of systematic reviews favored not utilizing a tourniquet due to the decrease in complication rate and the improvement in clinical results. While it is standard practice in the US to utilise a tourniquet, the strong consensus of the literature on the subject favors either not using a tourniquet or minimizing the use of a tourniquet for the period of time necessary for a very dry field for cement fixation

Tourniquet is widely used in orthopedic surgery to reduce intraoperative bleeding and improve visualization. We evaluated the effect of tourniquet application on both peri- and postoperative cefuroxime concentrations in subcutaneous tissue, skeletal muscle, calcaneal cancellous bone, and plasma. The primary endpoint was the time for which the free drug concentration of cefuroxime was maintained above the clinical breakpoint minimal inhibitory concentration (T>MIC) forStaphylococcus aureus (4 µg/mL). Ten patients scheduled for hallux valgus or hallux rigidus surgery were included. Microdialysis catheters were placed for sampling of cefuroxime concentrations bilaterally in subcutaneous tissue, skeletal muscle, and calcaneal cancellous bone. A tourniquet was applied on the thigh of the leg scheduled for surgery. Cefuroxime (1.5 g) was administered intravenously as a bolus 15 minutes prior to tourniquet inflation, followed by a second dose 6 hours later. The mean tourniquet duration (range) was 65 (58; 77) minutes. Dialysates and venous blood samples were collected for 12 hours. For cefuroxime the T>MIC (4 μg/mL) ranged between 4.8–5.4 hours across compartments, with similar results for the tourniquet and non-tourniquet leg. Comparable T>MIC and penetration ratios were found for the first and second dosing intervals. We concluded that administration of cefuroxime (1.5 g) 15 minutes prior to tourniquet inflation is safe in order to achieve tissue concentrations above 4 µg/mL throughout surgery. A tourniquet application time of approximately 1 hour did not affect the cefuroxime tissue penetration in the following dosing interval

Tourniquets have been used for many years during total knee arthroplasty (TKA). With a growing demand for TKA in recent years, tourniquet use has been surrounded by ongoing controversy due to many conflicting advantages and disadvantages of tourniquet use. Quantifying the case for or against tourniquet use in TKA, in terms of patient focused outcomes, is a priority. This meta-analysis analysed, the never before assessed, impact of tourniquet use during TKA on post-operative pain. We completed a systematic review and meta-analysis using PRISMA reporting guidelines to assess the impact of tourniquet use on patients post-TKA. Post-operative pain was the primary outcome. Secondary outcomes were post-operative range of motion (ROM) and length of stay (LOS). The initial search yielded 230 studies, of which 14 met the inclusion criteria. A post-operative increase in pain and reduction in ROM when using a tourniquet appeared significantly more likely when compared to no tourniquet use during TKA, yet with no overall difference in post-operative LOS. Subgroup meta-analysis demonstrated a trend that favoured the half-course tourniquet for reduced post-operative pain in patients when compared to full tourniquet use during TKA. This systematic review and meta-analysis concluded that the after-effects of tourniquet use in TKA patients and its impact on post-operative pain and ROM are indeed significant. We recommend further randomized controlled trials (RCTs) focusing on TKA patient outcomes of post-operative pain and ROM. Conflict of interest: The authors certify that they have NO affiliations with or involvement in any organization or entity with any financial interest (such as honoraria; educational grants; participation in speakers' bureaus; membership, employment, consultancies, stock ownership, or other equity interest; and expert testimony or patent-licensing arrangements), or non-financial interest (such as personal or professional relationships, affiliations, knowledge or beliefs) in the subject matter or materials discussed in this manuscript

In this study patients were randomized between surgeon chosen pressure (control) and an automatically determined tourniquet pressure(study group). Of 112 patients in the study group, 5% failed to obtain an automatic pressure. Of the remainder, the average tourniquet pressure was 198 +/− 20.2 mm Hg compared to 259.6 +/− 4.4 mmHg for the control group (p<0.0001). Of the study group 94 (88.6%) had good to excellent fields compared to the control group where 100 (77.5%) had good to excellent fields (p<0.05). The automatic measurement of limb occlusion pressure results in better operative fields at a lower pressure

Background. Tourniquets are routinely used in total knee arthroplasty (TKA) with an estimated use by up to 93% of surgeons. Advantages include the ability to provide a bloodless field of view to facilitate cement application and increase the success of the procedure. Overall reduction in blood loss is another perceived advantage, however recent research has demonstrated no measurable reduction and conversely a substantial increase in complications such as deep vein thrombosis and systemic emboli. Given the significant complications of tourniquet use we aim to identify patients’ views on tourniquets and of emphasis their awareness of the possible risks involved prior to the procedure. Method. A questionnaire-based study was carried out on 35 patients attending an elective orthopaedic centre for TKA surgery. Ethical approval was granted by NRES committee – East of England (REC Ref: 14/EE/1265). Patients were provided with an information sheet detailing the reasons for the tourniquet use and the associated risks and benefits. They were then provided with a questionnaire to ascertain their views and previous understanding of the subject. Simple statistical measures were implemented to analyse the data. Results. Only 32% of patients were aware of the use of tourniquets during the operation. 19% were aware of the benefits prior to reading the information sheet provided with 29% understanding the risks involved prior to their procedure. Finally we found 97% of patients would like more information on the use of tourniquets preoperatively. Conclusion. Tourniquets are widely used in TKA surgery, however, they carry significant risks which are not clearly relayed preoperatively to all patients. Given that 91,000 TKA operations are performed per year we believe it is of paramount importance that all patients are appropriately counselled on the risks and benefits of its use and fully informed consent, including risks of tourniquet use, should be obtained prior to the procedure. Level of Evidence. Level 3

Background. Tourniquets are routinely used in total knee arthroplasty (TKA) with an estimated use by up to 93% of surgeons. Advantages include the ability to provide a bloodless field of view to facilitate cement application and increase the success of the procedure. Overall reduction in blood loss is another perceived advantage, however recent research has demonstrated no measurable reduction and conversely a substantial increase in complications such as deep vein thrombosis and systemic emboli. Given the significant complications of tourniquet use we aim to identify patients' views on tourniquets and of emphasis their awareness of the possible risks involved prior to the procedure. Method. A questionnaire-based study was carried out on 35 patients attending an elective orthopaedic centre for TKA surgery. Ethical approval was granted by NRES committee – East of England (REC Ref: 14/EE/1265). Patients were provided with an information sheet detailing the reasons for the tourniquet use and the associated risks and benefits. They were then provided with a questionnaire to ascertain their views and previous understanding of the subject. Simple statistical measures were implemented to analyse the data. Results. Only 32% of patients were aware of the use of tourniquets during the operation. 19% were aware of the benefits prior to reading the information sheet provided with 29% understanding the risks involved prior to their procedure. Finally we found 97% of patients would like more information on the use of tourniquets preoperatively. Conclusion. Tourniquets are widely used in TKA surgery, however, they carry significant risks which are not clearly relayed preoperatively to all patients. Given that 91,000 TKA operations are performed per year we believe it is of paramount importance that all patients are appropriately counselled on the risks and benefits of its use and fully informed consent, including risks of tourniquet use, should be obtained prior to the procedure. Level of Evidence. Level 3

Objectives. The length of the tourniquet time during total knee arthroplasty (TKA) is related to the incidence of post-operative deep vein thrombosis (DVT). Our aim in this study was to investigate the effect of the early release of the tourniquet on the incidence of DVT in patients undergoing TKA. Methods. A total of 200 patients who underwent TKA between November 2015 and November 2016 were prospectively enrolled. The tourniquet was inflated before surgery and released immediately after the introduction of the components (early release group). This group was compared with a retrospective cohort of 200 primary TKAs, in which the tourniquet was released after the dressings had been applied (late release group). The presence of a DVT was detected using bilateral lower limb ultrasonography. Peri-operative clinical and follow-up data were collected for analysis. Results. The incidence of DVT in the early release group (9 of 196, 4.6%) was significantly lower compared with the late release group (24 of 200, 12%; odds ratio (OR) 0.35, 95% confidence interval (CI) 0.16 to 0.78, p = 0.008). The incidence of proximal DVT in the early release group (1 of 196 (0.5%)) was significantly lower than in the late release group (8 of 196, 4%; OR 0.12, 95% CI 0.02 to 0.99, p = 0.020). Although the mean intra-operative blood loss was higher in the early release group, the mean post-operative drainage, total blood loss, transfusion requirements and complications were not significantly different in the two groups. Conclusion. In patients who undergo TKA, releasing the tourniquet early is associated with a decreased incidence of DVT, without increasing the rate of complications. Cite this article: Bone Joint Res 2017;6:535–541