Effect of body mass index on functional outcome in primary total knee arthroplasty——a single institution analysis of 2180 primary total knee replacements

AIM To evaluate the effect of body mass index(BMI) on short-term functional outcome and complications in primary total knee arthroplasty. METHODS All patients undergoing primary total knee arthroplasty at a single institution between 2007 and 2013 were identified from a prospective arthroplasty database. 2180 patients were included in the study. Age, gender, BMI, pre- and post-operative functional scores [Western Ontario and Mc Master University Arthritis Index(WOMAC) and SF-36], complications and revision rate were recorded. Patients were grouped according to the WHO BMI classification. The functional outcome of the normal weight cohort(BMI < 25) was compared to the overweight and obese(BMI ≥ 25) cohort. A separate sub-group analysis was performed comparing all five WHO BMI groups; Normal weight, overweight, class 1 obese, class 2 obese and class 3 obese.RESULTS With a mean age of 67.89(28-92), 2180 primary total knee replacements were included. 64.36%(1403) were female. The mean BMI was 31.86(18-52). Ninty-three percent of patients were either overweight or obese. Mean follow-up 19.33 mo(6-60 mo). There was no significant difference in pre or post-operative WOMAC score in the normal weight(BMI < 25) cohort compared to patients with a BMI ≥ 25(P > 0.05). Sub-group analysis revealed significantly worse WOMAC scores in class 2 obese 30.80 compared to overweight 25.80(P < 0.01) and class 1 obese 25.50(P < 0.01). Similarly, there were significantly worse SF-36 scores in class 2 obese 58.16 compared to overweight 63.93(P < 0.01) and class 1 obese 63.65(P < 0.01) There were 32(1.47%) superficial infections, 9(0.41%) deep infections and 19(0.87%) revisions overall with no complications or revisions in the normal weight cohort(BMI < 25).CONCLUSION Post-operative functional outcome was not influenced by BMI comparing normal weight individuals with BMI > 25. Patients should not be denied total knee arthroplasty based solely on weight alone.

The Clinical Characteristics of Combined Deep Vein Thrombosis Prophylaxis of Rivaroxaban and Mechanical Therapy after Total Knee Replacement Arthroplasty

Purpose: To investigate the clinical characteristics of combined prophylaxis of rivaroxaban (Xarelto?) and mechanical therapy (foot sole pump, antiembolism stocking) after total knee replacement arthroplasty, for prevention of deep vein thrombosis (DVT). Materials and Methods: The subjects of this study were 110 patients who underwent total knee replacement arthroplasty (TKA) between November 2011 and May 2012, and were prospectively evaluated. They consisted of 13 men (11.8%) and 97 women (88.2%) with the mean age of 68.7 years (±7.9). All of the patients received 10 mg of rivaroxaban once daily for 14 days from Day 1 postoperatively, and used an intermittent pneumatic compression (IPC) pump and compression stockings immediately after the operation. To determine the presence of postoperative DVT, clinical symptoms examination, D-dimer test, color Doppler ultrasound imaging were performed to analyze the risk factors of DVT events. Results: There were a total of 13 patients (11.8%) with DVT in the distal lower limbs among the entire 110 patients. At Day 4 after the operation, a statistically significant difference was seen only in femoral swelling of several clinical symptoms between DVT group and non-DVT group (p = 0.043). D-dimer tests showed no statistically significant difference between the two groups, however with the boundary value of 0.3 mg/L, diagnostic sensitivity, specificity, positive predictability and negative predictability were equivalent to 100%, 8.2%, 12.7% and 100%, respectively. There was no significant difference between the two groups in terms of well-known risk factors including age, gender, obesity, hypertension, diabetes, smoking, and anesthesia method, and no case of pulmonary embolism was observed. Conclusion: A combination of pharmacological therapy (rivaroxaban, Xarelto?) and mechanical therapy (foot sole pump system) after TKA is considered effective for DVT prevention.

Insights into complications after unicompartmental knee arthroplasty

Zhao's study,offers a comprehensive analysis of unicompartmental knee arthroplasty(UKA)revision indications.The study provides a detailed,case-by-case analysis of the factors leading to knee revision surgery in 13 patients.Not only elucidates the complexities of UKA revisions but also underscores the importance of continuous improvement in surgical techniques and the adoption of innovative technologies.

Multidisciplinary approach toward enhanced recovery after surgery for total knee arthroplasty improves outcomes

Knee osteoarthritis is a degenerative disorder of the knee,which leads to joint pain,stiffness,and inactivity and significantly affects the quality of life.With an increased prevalence of obesity and greater life expectancies,total knee arthroplasty(TKA)is now one of the major arthroplasty surgeries performed for knee osteoarthritis.When enhanced recovery after surgery(ERAS)was introduced in TKA,clinical outcomes were enhanced and the economic burden on the healthcare system was reduced.ERAS is an evidence-based scientific protocol aimed at ameliorating the surgical stress response.ERAS aims to enhance the recovery phase,which encompasses multidisciplinary strategies at every step of perioperative care,including the rehabilitation phase.Implementation of ERAS in TKA aids in reducing the length of hospital stay,improving pain management,reducing perioperative complications,and enhancing patient satisfaction.Multidisciplinary collaboration,integrating the expertise of anesthesiologists,orthopedic surgeons,nursing personnel,and other healthcare professionals,is the cornerstone of ERAS in patients undergoing TKA.

How to manage and avoid revision after unicompartmental knee arthroplasty?

The article by Zhao et al presents a retrospective case series on the reasons for initial revision after unicompartmental knee arthroplasty(UKA).Clarifying the reasons that may cause UKA revision can further reduce the rate of revision UKA,focusing on gasket dislocation,osteophytes,intra-articular loose bodies,and tibial prosthesis loosening.This article provides valuable insights,not only by detailing the revision status of 13 patients who underwent revision after initial UKA but also by providing a comprehensive analysis of the incidence of revision after initial UKA.By reviewing and analyzing the causes,they established references for the early detection of risk factors for revision in clinical practice and for formulating surgical strategies and rehabilitation programmes.This commentary emphasizes the need for a meticulous understanding and an analysis of the revision rate following initial UKA and related management strategies.The implant rates,regional variation,and benefits of uncemented Oxford UKA have been explored,particularly in terms of bone preservation,appropriate surgical techniques,and weight management to control complications and improve patient prognosis.

Eight of ten patients return to daily activities, work, and sports after total knee arthroplasty

BACKGROUND Besides return to work(RTW)and return to sports(RTS),patients also prefer to return to daily activities(RTA)such as walking,sleeping,grocery shopping,and domestic work following total knee arthroplasty(TKA).However,evidence on the timelines and probability of patients’RTA is sparse.AIM To assess the percentage of patients able to RTA,RTW,and RTS after TKA,as well as the timeframe and influencing factors of this return.METHODS A retrospective cohort study with prospectively collected data was conducted at a medium-sized Dutch orthopedic hospital.Assessments of RTA,RTW,and RTS were performed at 3 mo and/or 6 mo following TKA.Investigated factors en-compassed patient characteristics,surgical characteristics,and preoperative patient-reported outcomes.RESULTS TKA patients[n=2063;66 years old(interquartile range[IQR]:7 years);47%male;28 kg/m2(IQR:4 kg/m2)]showed RTA ranging from 28%for kneeling to 94%for grocery shopping,with 20 d(IQR:27 d)spent for putting on shoes to 74 d(IQR:57 d)for kneeling.RTW rates varied from 62%for medium-impact work to 87%for low-impact work,taking 33 d(IQR:29 d)to 78 d(IQR:55 d).RTS ranged from 48%for medium-impact sports to 90%for low-impact sports,occurring within 43 d(IQR:24 d)to 90 d(IQR:60 d).One or more of the investigated factors influenced the return to each of the 14 activities examined,with R²values ranging from 0.013 to 0.127.CONCLUSION Approximately 80%of patients can RTA,RTW,and RTS within 6 mo after TKA.Return is not consistently in-fluenced by predictive factors.Results help set realistic pre-and postoperative expectations.

Possible Risk Factors for Severe Complications Occurring after Primary Total Knee Arthroplasty

Objective Total knee arthroplasty is one of the most common orthopedic surgeries.Readmission due to severe complications after total knee arthroplasty is a grave concern to surgeons.In this study,we evaluated the risk factors for severe complications after primary total knee arthroplasty.Methods We retrospectively collected clinical data of 2,974 patients who underwent primary total knee arthroplasty from July 2013 to June 2019 in our hospital.Postoperative complication≥gradeⅢwas defined as severe complication according to Clavien-Dindo classification system.Binary logistic regression was used to identify the predictive risk factors for severe complications.Results The complication rate after primary total knee arthroplasty was 6.8%and severe complication rate was 2.5%.Male(OR=2.178,95%CI:1.324-3.585,P=0.002),individuals above 75 years old(OR=1.936,95%CI:1.155-3.244,P=0.012),arrhythmia(OR=2.913,95%CI:1.350-6.285,P=0.006)and cerebrovascular disease(OR=2.804,95%CI:1.432-5.489,P=0.003)were predictive risk factors for severe complications after primary total knee arthroplasty.Conclusion Advanced age,male,arrhythmia,and cerebrovascular disease might be patients-related risk factors for postoperative severe complications after primary total knee arthroplasty.Special attention should be paid to patients with risk factors.

New Classification and Visual Analysis of the Patella Cartilage during Total Knee Replacement

Objective: The aim of this prospective study is to evaluate how much damage the patellar cartilage presents during a total knee replacement. Methods: The damage of the articular patellar surface was analysed by visual inspection and photographs in 354 primary total knee replacements. The authors graded the degree of cartilage lesion in five groups. The cartilage status was analyzed and correlated with age, gender, side, body mass index (BMI), Kellgren-Lawrence radiographic scale and axial deviation. Results: After statistical analysis, we concluded: there was no evidence of an association between patellar arthrosis and age gender, side, weight and deformity. Conclusions: Articular cartilage was damaged in all 354 knees. Important subchondral bone exposure occurred in 274 knees (77.4%). Obese patients had more severe patellar osteoarthritis.

Clinical,Laboratory and Echografic Evaluation of Patients with Deep Vein Thrombosis Following Total Knee Arthroplasty

Introduction: Total knee arthroplasty, being a major surgery, carries a risk of post-operative deep vein thrombosis (DVT). The main objective of the present study was to elucidate the association of clinical, laboratory, and echographic findings with the occurrence of DVT. Patients and Methods: The present study was prospective and non-randomized, with restricted exclusion criteria. Forty patients were submitted to total knee arthroplasty due to osteoarthritis. Patients were clinically evaluated by laboratory tests, assessment of pain and calf circumference, and the presence of Homans’ sign. Echo Doppler was performed in each patient on postoperative day 7. The echographic evaluation divided the patients into two groups: positive (G1) and negative for thrombosis (G2). All patients received prophylactic heparin during the 7-day hospital admission. Results: Eleven patients complained of pain (analgesic medication was used during the entire admission). Leg circumference variation from the pre-operative period to post-operative day 7 was: G1, 1.70 ± 1.12 cm and G2, 0.68 ± 1.25 cm (p = 0.03). Homans’ sign was considered positive in 10 patients. Echographic evaluation was positive in 11 patients (27.5%). No cases of pulmonary embolism, infection, or death were observed. Conclusions: The incidence of DVT was 27.5%, with an increase in leg circumference being the main predictive factor (p = 0.03).

Anterior knee pain following primary total knee arthroplasty

Despite improvements in technique and technology for total knee arthroplasty(TKA),anterior knee pain impacts patient outcomes and satisfaction.Addressing the prosthetic and surgical technique related causes of pain after TKA,specifically as it relates to anterior knee pain,can aid surgeons in addressing these issues with their patients.Design features of the femoral and patellar components which have been reported as pain generators include: Improper femoral as well as patellar component sizing or designs that result in patellofemoral stuffing; a shortened trochlear groove distance from the flange to the intercondylar box; and then surgical technique related issues resulting in: Lateral patellar facet syndrome; overstuffed patella/flange combination; asymmetric patellar resurfacing,improper transverse plane component rotation resulting in patellar subluxation/tilt.Any design consideration that allows impingement of extensor mechanism anatomical elements has the possibility of impacting outcome by becoming a pain generator.As the number of TKA procedures continues to increase,it is increasingly critical to develop improved,evidence based prostheses that maximize function and patient satisfaction while minimizing pain and other complications.

Perioperative blood management strategies for patients undergoing total knee replacement:Where do we stand now?

Total knee replacement(TKR) is one of the most common surgeries over the last decade. Patients undergoing TKR are at high risk for postoperative anemia and furthermore for allogeneic blood transfusions(ABT). Complications associated with ABT including chills, rigor, fever, dyspnea, light-headedness should be early recognized in order to lead to a better prognosis. Therefore, perioperative blood management program should be adopted with main aim to reduce the risk of blood transfusion while maximizing hemoglobin simultaneously. Many blood conservation strategies have been attempted including preoperative autologous blood donation, acute normovolemic haemodilution, autologous blood transfusion, intraoperative cell saver, drain clamping, pneumatic tourniquet application, and the use of tranexamic acid. For practical and clinical reasons we will try to classify these strategies in three main stages/pillars: Pre-operative optimization, intra-operative and post-operative protocols. The aim of this work is review the strategies currently in use and reports our experience regarding the perioperative blood management strategies in TKR.

Minimally invasive knee arthroplasty: An overview

Minimally invasive surgery(MIS) for arthroplasty of the knee began with surgery for unicondylar knee arthroplasty(UKA).Partial knee replacements were designed in the 1970 s and were amenable to a more limited exposure.In the 1990 s Repicci popularized the MIS for UKA.Surgeons began to apply his concepts to total knee arthroplasty.Four MIS surgical techniques were developed: quadriceps sparing,mini-mid vastus,mini-subvastus,and minimedial parapatellar.The quadriceps sparing technique is the most limited one and is also the most difficult.However,it is the least invasive and allows rapid recovery.The mini-midvastus is the most common technique because it affords slightly better exposure and can be extended.The mini-subvastus technique entirely avoids incising the quadriceps extensor mechanism but is time consuming and difficult in the obese and in the muscular male patient.The mini-parapatellar technique is most familiar to surgeons and represents a good starting point for surgeons who are learning the techniques.The surgeries are easier with smaller instruments but can be performed with standard ones.The techniques are accurate and do lead to a more rapid recovery,with less pain,less blood loss,and greater motion if they are appropriately performed.

Randomised controlled trial of triclosan coated vs uncoated sutures in primary hip and knee arthroplasty

BACKGROUND Triclosan-coated vicryl plus suture(Ethicon, Inc.) was developed to reduce microbial colonisation during surgical procedures. However, its effect on wound healing and surgical site infections remain unclear after hip and knee arthroplasty surgery.AIM To determine the effect of triclosan-coated sutures(TCS) vs non-coated sutures on wound healing, following primary hip and knee arthroplasties.METHODS A single-centred, double-blind randomised controlled trial(RCT) was undertaken. We randomly allocated patients to receive either the triclosan-coated sutures(TCS vicryl plus) or non-coated sutures(NCS vicryl) during the closure of unilateral primary hip and knee arthroplasties. We utilised the ASEPSIS wound scoring system to evaluate wound healing for the first 6 weeks post-operatively.RESULTS One hundred and fifty patients undergoing primary total hip or knee arthroplasty over a one-year period were included. Eighty-one were randomised to the TCS group and 69 to the NCS group. Despite no statistically significant difference in the ASEPSIS scores among the study groups(P = 0.75), sensitivity analysis using the Mann Whitney test(P = 0.036) as well as assessment of the wound complications at 6 weeks follow up, demonstrated significantly higher wound complication rates in the TCS group(8 vs 1, P = 0.03).CONCLUSION No clear advantage was demonstrated for using the TCS. However, larger multicentred RCTs are required to validate their use in hip and knee arthroplasty surgery.

Total knee arthroplasty:Effect of obesity and other patients' characteristics on operative duration and outcome

AIM: To examine the effects of patients' characteristics mainly obesity on operative duration and other outcomemeasures of knee arthroplasty. METHODS: This is a retrospective chart review of 204 patients who had knee arthroplasty within the past five years(2007-2011) at King Abdulaziz Medical City in Riyadh, Kingdom of Saudi Arabia. The data collection form was developed utilizing the literature review to gather all the needed variables. Data were gathered from admission notes, nursing notes, operative reports and discharge summaries.RESULTS: A feasible sample of 204 patients were included in the study. Of those patients, 155(76%) were females. The mean age was 70.1 years for males(SD ± 9.4) and 62.7 years(SD ± 8) for females. Regarding the type of total knee replacement(TKR), 163(79.9%) patients had unilateral TKR and 41(20.1%) had bilateral TKR. Nine patients(4.4%) had a normal body mass index(BMI)(18.5 to < 25). Overweight patients(BMI 25 to < 30) represented 18.1%. Obesity class Ⅰ(BMI 30 to < 35) and obesity class Ⅱ(BMI from 35 to < 40) were present in 23% and 29.9% of the patients, respectively. Morbid obesity(BMI greater than 40) was present in 24.5%. The mean duration of surgery was 126.3 min(SD ± 30.8) for unilateral TKR and 216.6 min(SD ± 55.4) for bilateral TKR.The mean length of stay in the hospital was 12 d(SD ± 4.9). The complications that patients had after the operation included 2 patients(1%) who developed deep venous thrombosis, 2 patients(1%) developed surgical wound infections and none had pulmonary embolism. Patients' characteristics(including age, gender, BMI and co-morbidities) did not have an effect on the operative duration of knee replacement nor the length of hospital stay. CONCLUSION: Our study shows that obesity and other patients' characteristics do not have effect on the operative duration nor the length of hospital stay following TKR.

Computerized tomography based “patient specific blocks” improve postoperative mechanical alignment in primary total knee arthroplasty

AIM: To compare the postoperative mechanical alignment achieved after total knee arthroplasty(TKA) using computer tomography(CT) based patient specific blocks(PSB) to conventional instruments(CI).METHODS: Total 80 knees were included in the study, with 40 knees in both the groups operated using PSB and CI. All the knees were performed by a single surgeon using the same cruciate sacrificing implants. In our study we used CT based PSB to compare with CI. Postoperative mechanical femoro-tibial angle(MFT angle) was measured on long leg x-rays using picture archiving and communication system(PACS). We compared mechanical alignment achieved using PSB and CI in TKA using statistical analysis.RESULTS: The PSB group(group 1) included 17 females and seven males while in CI group(group 2) there were 15 females and eight males. The mean age of patients in group 1 was 60.5 years and in group 2 it was 60.2 years. The mean postoperative MFT angle measured on long-leg radiographs in group 1 was 178.23°(SD = 2.67°, range: 171.9° to 182.5°) while in group 2, the mean MFT angle was 175.73°(SD = 3.62°, range: 166.0° to 179.8°). There was significant improvement in postoperative mechanical alignment(P value = 0.001), in PSB group compared to CI. Number of outliers were also found to be less in group operated with PSB(7 Knee) compared to those operated with CI(17 Knee).CONCLUSION: PSB improve mechanical alignment after total knee arthroplasty, compared to CI. This may lead to lower rates of revision in the PSB based TKA as compared to the conventional instrumentation.

Early patellar tendon rupture after total knee arthroplasty: A direct repair method

BACKGROUND Patellar tendon rupture after total knee arthroplasty(TKA)is a catastrophic complication.Although the occurrence of this injury is rare,it can lead to significant dysfunction for the patient and is very tricky to deal with.There has been no standard treatment for early patella tendon rupture after TKA,and long-term follow-up data are lacking.AIM To introduce a direct repair method for early patella tendon rupture following TKA and determine the clinical outcomes and complications of this method.METHODS During the period of 2008 to 2021,3265 consecutive TKAs were retrospectively reviewed.Twelve patients developed early patellar tendon rupture postoperatively and were treated by a direct repair method.Mean follow-up was 5.7 years.Demographic,operative,and clinical data were collected.The clinical outcomes were assessed using the Western Ontario and McMaster Universities(WOMAC)score,the Hospital for Special Surgery(HSS)score,knee range of motion,extensor lag,and surgical complications.Descriptive statistics and paired t test were employed to analyze the data.RESULTS For all 12 patients who underwent direct repair for early patellar tendon rupture,3 patients failed:One(8.3%)for infection and two(17.6%)for re-fracture.The two patients with re-fracture both underwent reoperation to reconstruct the extensor mechanism and the patient with infection underwent revision surgery.The range of motion was 109.2°±10.6°preoperatively to 87.9°±11°postoperatively,mean extensor lag was 21°at follow-up,and mean WOMAC and HSS scores were 65.8±30.9 and 60.3±21.7 points,respectively.CONCLUSION This direct repair method of early patellar tendon rupture is not an ideal therapy.It is actually ineffective for the recovery of knee joint function in patients,and is still associated with severe knee extension lag and high complication rates.Compared with the outcomes of other repair methods mentioned in the literature,this direct repair method shows poor clinical outcomes.

Socio-demographic factors impact time to discharge following total knee arthroplasty

AIM To determine social, logistical and demographic factors that influence time to discharge in a short stay pathway(SSP) by following total knee arthroplasty(TKA). METHODS The study included primary TKA's performed in a highvolume arthroplasty center from January 2016 through December 2016. Potential variables associated with increased hospital length of stay(LOS) were obtained from patient medical records. These included age, gender, race, zip code, body mass index(BMI), number of pre-operative medications used, number of narcotic medications used, number of patient reported allergies(PRA), simultaneous bilateral surgery, tobacco use, marital status, living arrangements, distance traveled for surgery, employment history, surgical day of the week, procedure end time and whether the surgery was performed during a major holiday week. Multivariate step-wise regression determined the impact of social, logistical and demographic factors on LOS. RESULTS Eight hundred and six consecutive primary SSP TKA's were included in this study. Patients were discharged at a median of 49 h(post-operative day two). The following factors increased LOS: Simultaneous bilateral TKA [46.1 h longer(P < 0.001)], female gender [4.3 h longer(P = 0.012)], age [3.5 h longer per ten-year increase in age(P < 0.001)], patient-reported allergies [1.1 h longer per allergy reported(P = 0.005)], later procedure endtimes [0.8 h longer per hour increase in end-time(P = 0.004)] and Black or African American patients [6.1 h longer(P = 0.047)]. Decreased LOS was found in married patients [4.8 h shorter(P = 0.011)] and TKA's performed during holiday weeks [9.4 h shorter(P = 0.011)]. Non-significant factors included: BMI, median income, patient's living arrangement, smoking status, number of medications taken, use of pre-operative pain medications, distance traveled to hospital, and the day of surgery. CONCLUSION The cost of TKA is dependent upon LOS, which is affected by multiple factors. The clinical care team should acknowledge socio-demographic factors to optimize LOS.

Effect of enhanced recovery after surgery with multidisciplinary collaboration on nursing outcomes after total knee arthroplasty

BACKGROUND There is a lack of studies on the effects of enhanced recovery after surgery(ERAS)with multidisciplinary collaboration on the nursing outcomes of total knee arthroplasty(TKA).AIM To explore the effect of ERAS with multidisciplinary collaboration on nursing outcomes after TKA.METHODS We retrospectively analyzed the clinical data of 80 patients who underwent TKA at a tertiary hospital between January 2021 and December 2022.The patients were divided into two groups according to the nursing mode:the ERAS group(n=40)received ERAS with multidisciplinary collaboration,and the conventional group(n=40)received routine nursing.The following indicators were compared between the two groups:length of hospital stay,hospitalization cost,intraoperative blood loss,hemoglobin level 24 h after surgery,visual analog scale(VAS)score for pain,range of motion(ROM)of the knee joint,Hospital for Special Surgery(HSS)knee score,and postoperative complications.RESULTS The ERAS group had a significantly shorter length of hospital stay,lower hospitalization cost,less intraoperative blood loss,higher hemoglobin level 24 h after surgery,lower VAS score for pain,higher knee joint ROM,and higher HSS knee score than the conventional group(all P<0.05).There was no significant difference in the incidence of postoperative complications between the two groups(P>0.05).CONCLUSION Multidisciplinary collaboration with ERAS can reduce blood loss,shorten hospital stay,and improve knee function in patients undergoing TKA.

Sevoflurane Preconditioning and Total Knee Arthroplasty Bleeding: Randomized Controlled Trial

Background: Total knee arthroplasty (TKA) is a highly complex and effective surgery even though its perioperative bleeding may increase the need for blood transfusion and its associated infection risk, cardiovascular overload, increased costs, and mortality. As the tourniquet reduces intraoperative bleeding, it may be associated with postoperative bleeding, venous thrombosis, and distal ischemia. The reperfusion may trigger a local and systemic inflammatory response. Anesthetic preconditioning (APC) with sevoflurane minimizes ischemia-reperfusion syndrome (IRS). This study evaluated the effects of APC with sevoflurane on perioperative bleeding in TKA. Methods: We allocated 30 patients into two groups: a sevo group (sevoflurane 2% for 15 minutes before the tourniquet) and a control group (propofol infusion). Laboratory tests were collected right before the tourniquet (LAB PRE, in the operating room) and after its release at four moments: LAB POST (immediately after), LAB 2 (two hours after), LAB 12 (12 hours after), and LAB 24 (24 hours after). The volume of the suction drain was measured at one, two, 12, and 24 hours after the end of the surgery. Antifibrinolytics were not administered. Results: There was no statistically significant difference in bleeding-related variables, such as drained volume and hemoglobin and hematocrit measurements. Drainage volume was higher in the first two hours after the procedure, while hematocrit decreased pre- to postoperatively and between two and 12 hours post-procedure. Conclusion: Sevoflurane as an anesthetic preconditioning did not reduce postoperative bleeding in TKA surgery.

Limb length discrepancy after total knee arthroplasty: A systematic review and meta-analysis

BACKGROUND Limb length discrepancy(LLD)after total knee arthroplasty(TKA)has been considered as one of the reasons for the unsatisfactory outcome.However,there is no consensus about the extent of LLD that can be considered as clinically relevant.AIM To evaluate the incidence of radiographic LLD and its impact on functional outcome following TKA.METHODS All randomized-controlled trial and observational studies on LLD in TKA,published till 22nd June 2020,were systematically searched and reviewed.The primary outcome was“limb lengthening or LLD after TKA”.The secondary outcomes included“assessment of LLD in varus/valgus deformity”and“impact of LLD on the functional outcome”.RESULTS Of 45 retrieved studies,qualitative and quantitative assessment of data was performed from eight studies and six studies,respectively.Five studies(n=1551)reported the average limb lengthening of 5.98 mm.The LLD after TKA was ranging from 0.4±10 mm to 15.3±2.88 mm.The incidence of postoperative radiographic LLD was reported in 44%to 83.3%of patients.There was no difference in the preoperative and postoperative LLD(MD-1.23;95%CI:-3.72,1.27;P=0.34).Pooled data of two studies(n=219)revealed significant limb lengthening in valgus deformity than varus(MD-2.69;95%CI:-5.11,0.27;P=0.03).The pooled data of three studies(n=611)showed significantly worse functional outcome in patients with LLD of≥10 mm compared to<10 mm(standard MD 0.58;95%CI:0.06,1.10;P=0.03).CONCLUSION Limb lengthening after TKA is common,and it is significantly more in valgus than varus deformity.Significant LLD(≥10 mm)is associated with suboptimal functional outcome.