Tourniquet Use Improves Cement Penetration and Reduces Radiolucent Line Progression at 5 Years After Total Knee Arthroplasty

Impact of tourniquet use in total knee arthroplasty on functional recovery and postoperative pain: a prospective study

BACKGROUND

Tourniquet use during total knee arthroplasty (TKA) remains controversial. The purpose of this study is to determine the impact of tourniquet use only during cementation compared with its use throughout the entire surgery concerning early outcomes in functional recovery, pain, quadriceps function, and rehabilitation.

METHODS

Between November 2019 and March 2020, 118 patients were enrolled in this study, with 59 patients undergoing TKA with a tourniquet during the entire surgery (group 1) and 59 patients with a tourniquet only during cementation (group 2). Twenty-eight patients were unable to complete follow-up leaving fifty in group 1 and forty in group 2. Primary endpoints were surgical time, postoperative knee and thigh pain, and functional recovery. Secondary endpoints were 6-month clinical scores and blood loss.

RESULTS

Patients in group 1 had statistically significantly increased knee pain on postoperative day 3 (p = 0.004), and thigh pain on postoperative day 1 (p < 0.001), 2 (p < 0.001), and 3 (p = 0.027), and longer time intervals to achieve straight leg raise maneuver (p = 0.006) compared to group 2. However, it did not affect overall narcotic consumption, knee pain (day 1-2), functional recovery, ROM, ability to do the first walk, Oxford knee score, length of stay, and complication rate. There was no statistically significant difference in terms of 6-month postoperative knee score, surgical time, and blood loss between the two groups.

CONCLUSION

Tourniquet use diminishes quadriceps function and increases postoperative thigh pain and, to a lesser extent, knee pain. We, therefore, recommend the use of a tourniquet only during cementing.

LEVEL OF EVIDENCE

1; prospective randomized study.

Comparative Efficacy of iPACK vs Popliteal Sciatic Nerve Block for Pain Management Following Total Knee Arthroplasty: A Retrospective Analysis

Introduction Total knee arthroplasty (TKA) is associated with severe acute postoperative pain. The use of tourniquets and drains (T/D) is common in TKA but may have an influence on postoperative pain and muscular strength. The infiltration of local anesthetic between the popliteal artery and capsule of the knee (iPACK block) is a motor-sparing block that provides analgesia to the posterior aspect of the knee. However, evidence regarding its efficacy is scarce. This study aims to assess the effectiveness of iPACK block and the impact of T/D use on pain and muscular strength after TKA. Material and methods A retrospective study was carried out including patients who underwent TKA from January 2020 to April 2023. Patients were allocated into groups according to the peripheral nerve block performed and T/D use. Results We included 415 patients in this study. No differences were found in pain at rest or the need for rescue analgesia between patients who received an iPACK block or sciatic nerve block (SNB) with T/D applied. Patients who received a SNB reported lower pain scores on movement (p = 0.019), but with a higher prevalence of motor block (p < 0.001). Patients who underwent surgery without using T/D reported lower pain scores on movement (p = 0.021) and reduced need for rescue analgesia (p = 0.041). Conclusion These findings indicate that iPACK block can facilitate early mobilization after TKA without significant impact on postoperative muscle strength. Furthermore, the use of a T/D may be a source of postoperative pain that could compromise early rehabilitation.

The temporal effects of variable tourniquet use on pain after total knee arthroplasty

BACKGROUND

Tourniquet use in total knee arthroplasty (TKA) remains controversial. While widely studied, any temporal effects on pain and opioid utilization have not been investigated. We hypothesized that postoperative opioid utilization increases with increasing tourniquet times in TKA.

METHODS

We retrospectively reviewed 1110 TKAs by three arthroplasty surgeons from October 2016 through September 2019. Exclusion criteria included ambulatory surgery, undocumented tourniquet times, simultaneous bilateral TKA, and diagnoses other than osteoarthritis, inflammatory arthritis, or osteonecrosis. Postoperative opioid medications were converted to daily morphine milligram equivalents (MME/day). Secondary outcomes included range of motion (ROM) at 1-month, 3-month, and 1-year visits as well as patient reported outcomes measures (PROMs) at 3 and 12 months.

RESULTS

Nine-hundred and eleven patients were included and stratified based on tourniquet use. Three-hundred and four patients were assigned to a "No Use" group (≤10'); 138 patients to "Low Use" (11-60'); 177 patients to "Medium Use" (61-90'); and 292 patients to "Prolonged Use" (91-120). Compared to No Use, MME/day was significantly increased with Medium Use (+7.676 MME/day, p = 0.001) and Prolonged Use (+12.44 MME/day, p =< 0.001). No significant differences were found between No Use and Low Use groups. Estimated blood loss (EBL) in Low Use and No Use groups was significantly increased compared to other groups (+120 mL, p < 0.001, +109 mL, p < 0.001 respectively). Post-operative ROM and complication rates were similar between groups at 1 year post-TKA.

CONCLUSIONS

A threshold of 60 min of tourniquet time is associated with increased MME/day postoperatively compared to No Tourniquet. Functional and patient-reported outcomes are comparable between groups at 1 year follow-up.

With or without a Tourniquet? A Comparative Study on Total Knee Replacement Surgery in Patients without Comorbidities

Background and Objectives: This study aimed to determine the effects of tourniquet use and the complications of total knee arthroplasty (TKA) in patients without comorbidities to investigate whether tourniquet application can be employed without adverse effects and to assess its impact on the occurrence of any complications. Materials and Methods: A total of 106 patients who underwent unilateral TKA were divided randomly into two groups according to whether a tourniquet was used during the surgery or not. Patients with comorbidities (except arterial hypertension) were excluded from the study. Knee Injury and Osteoarthritis Outcome Score, joint range of motion, visual analog scale (VAS) score, total blood loss during and after surgery, postoperative analgesic consumption, and side effects were the main factors evaluated in the study. Results: In the tourniquet group, where the VAS scores were higher, the use of analgesics was also significantly higher. While there was no statistically significant difference in total blood loss between the tourniquet and non-tourniquet groups, the postoperative and occult blood losses were higher in the tourniquet group. The differences between the two groups in all other parameters were very small and not statistically significant. Conclusions: The findings of the current study suggest that when the comorbidities of patients are thoroughly documented and clarified prior to surgery, tourniquets should be applied selectively to individuals without any pre-existing health conditions.

Silicone ring tourniquet could be a substitute for a conventional tourniquet in total knee arthroplasty with a longer surgical field: a prospective comparative study in simultaneous total knee arthroplasty

INTRODUCTION

This study aimed to compare the clinical outcomes of silicon ring tourniquets and conventional pneumatic tourniquets in total knee arthroplasty (TKA). The study compared the operation time, total bleeding amount, length from the tourniquet distal end to the patella superior pole (L_TP), and complications related to the two tourniquet application methods and attempted to determine whether the silicon ring tourniquet has advantages over conventional pneumatic tourniquets.

MATERIALS AND METHODS

This prospective comparative study included 30 patients who underwent bilateral simultaneous TKA for degenerative osteoarthritis in August to December 2021. All patients underwent TKA on one side with a conventional pneumatic tourniquet, while TKA on the other side with a silicon ring tourniquet. The primary outcomes were the L_TP, operation time, tourniquet time, total bleeding amount, total drainage amount, and postoperative visual analog scale (VAS) score of the tourniquet applied site at 6, 24, and 48 h postoperatively. The secondary outcome was tourniquet-related complications in both groups.

RESULTS

L_TP was significantly longer in the silicon ring tourniquet group compared with that in the pneumatic tourniquet group (20.22 ± 2.74 cm versus 15.12 ± 2.40, p < 0.001). No significant difference was found in other results. The tourniquet applied site pain was less in the silicon ring tourniquet group (p = 0.037).

CONCLUSIONS

Silicon ring tourniquet application resulted in better clinical outcomes than conventional pneumatic tourniquets in TKA. Because we can obtain a wider surgical field using silicon ring tourniquets without complications, silicon ring tourniquets could be a substitute for conventional pneumatic tourniquets in total knee arthroplasty or distal femoral surgeries.

Tourniquets can further reduce perioperative blood loss in patients on dexamethasone and tranexamic acid during cemented total knee arthritis: a single-center, double-blind, randomized controlled trial

BACKGROUND

Multiple doses of dexamethasone and tranexamic acid can inhibit postoperative inflammation and reduce fibrinolysis and perioperative blood loss in total knee arthroplasty. In this single-center, double-blind, randomized clinical trial, the aim was to investigate whether applying a tourniquet to patients on dexamethasone and tranexamic acid could further reduce perioperative blood loss.

MATERIALS AND METHODS

Patients who underwent cemented total knee arthroplasty at our hospital were randomized to receive a tourniquet (n = 71) or not (n = 70) during the procedure. All patients received multiple doses of dexamethasone and tranexamic acid perioperatively. The primary outcome was perioperative blood loss, while secondary outcomes were surgery duration, postoperative laboratory indices of inflammation and fibrinolysis, range of knee motion, VAS pain score, knee circumference, knee swelling rate, homologous transfusion, albumin use, and complications.

RESULTS

Using a tourniquet was associated with significantly lower intraoperative blood loss (P < 0.001) and total blood loss (P = 0.007) as well as significantly shorter surgery duration (P < 0.001). In contrast, the tourniquet did not significantly affect hidden blood loss, postoperative inflammation or fibrinolysis, range of knee motion, VAS pain score, knee circumference, knee swelling rate, homologous transfusion, albumin use, or complications.

CONCLUSIONS

The results of this randomized clinical trial demonstrate that applying a tourniquet during cemented total knee arthroplasty to patients receiving multiple doses of dexamethasone and tranexamic acid can further reduce perioperative blood loss without increasing the risk of inflammation, fibrinolysis, or other complications. Thus, it is advised to use tourniquets combined with dexamethasone and tranexamic acid to reduce perioperative blood loss and avoid tourniquet-related adverse events.

LEVEL OF EVIDENCE

Therapeutic Level I. Trial registration Chinese Clinical Trail Registry, ChiCTR2200060567. Registered 5 June 2022-retrospectively registered, http://www.chictr.org.cn/showproj.aspx?proj=171291.

Tourniquet use does not impact trajectory of total knee arthroplasty early recovery: A prospective, randomized controlled trial

BACKGROUND

The impact of tourniquet use on recovery after total knee arthroplasty (TKA) remains controversial. The purpose of this prospective, single blinded, randomized controlled trial, was to investigate the effect of tourniquet use on early recovery after TKA using a smartphone app-based patient engagement platform (PEP) with a wrist-based activity monitor to obtain more robust data on early recovery.

METHODS

There were 107 patients undergoing primary TKA for osteoarthritis who were enrolled (54 tourniquet [TQ+]; 53 no tourniquet [TQ-]). All patients utilized a PEP and wrist-based activity sensor for two weeks preoperatively and 90 days postoperatively to collect Visual Analog Scale (VAS) pain scores and opioid consumption, as well as weekly Oxford Knee Score (OKS) and monthly Forgotten Joint Score (FJS). There was no difference in demographics between groups. Formal physical therapy assessments were performed preoperatively and 3 months postoperatively. Independent sample t-tests were used for continuous data and Chi-squared and Fisher's exact tests were used for discrete data.

RESULTS

Tourniquet use did not have a statistically significant impact on daily VAS pain or opioid consumption during the first 30 days postoperatively (P > 0.05). Tourniquet use did not have a significant impact on OKS or FJS at 30 or 90 days postoperatively (P> 0.05), or on performance of formal physical therapy testing at 3 months postoperatively (P> 0.05).

CONCLUSIONS

Using a digital technology to collect daily patient data, we found that tourniquet use has no clinically significant negative impact on pain and function in the first 90 days after primary TKA.

Staged replacement of both hips and both knees in patients with rheumatoid arthritis

BACKGROUND

Patients with rheumatoid arthritis (RA) undergoing bilateral total hip arthroplasty (THA) and total knee arthroplasty (TKA) are an uncommon population, and their outcomes are also difficult to predict. The purpose of this study was to evaluate whether both bilateral cementless THA and cemented posterior-stabilized TKA (PS-TKA) can provide reliable outcomes for RA patients.

METHODS

We retrospectively reviewed 30 RA patients (60 hips and 60 knees) who underwent both elective bilateral cementless THA and cemented PS-TKA, with a minimum follow-up of 2 years. Clinical, patient-reported, and radiographic data were retrospectively analyzed.

RESULTS

The mean follow-up was 84 months (range, 24-156). By the last follow-up, the post-operative range of motion, Harris Hip Score, Knee Society Score (KSS) clinical, KSS functional, Western Ontario and McMaster Universities Index of Osteoarthritis (WOMAC) hip, and WOMAC knee scores were significantly improved compared to the preoperative values. All patients achieved the ability to walk. In addition, overall satisfaction scores on a 100-point scale were 92.5 after THA and 89.6 after TKA. Only one patient underwent revision surgery due to knee joint instability, and all replaced hips and knees were radiographically stable by the assessment of the radiolucent line. The proportion of implants that did not suffer loosening or require revision surgery was 99.2% during the 84-month follow-up, based on Kaplan-Meier analysis.

CONCLUSIONS

Our study suggests that bilateral cementless THA and cemented PS-TKA provides reliable mid-long-term clinical, patient-reported, and radiographic outcomes in RA patients, with high survivorship and patient satisfaction.

Are There More Radiolucent Lines in Patients Who Underwent Total Knee Arthroplasty With or Without a Tourniquet During Cementation at 5 to 8 Years After Surgery?

BACKGROUND

This study investigated the presence and progression of radiolucent lines (RLLs) after cemented total knee arthroplasty (TKA) with or without tourniquet use.

METHODS

There were 369 consecutive primary cemented TKAs with 5 to 8 years of follow-up. A tourniquet was used during component cementation in patients who underwent surgery from January 3, 2006, to March 31, 2010. No tourniquet was used from August 14, 2009, to October 14, 2014. There were 192 patients in the tourniquet group (TQ) and 177 patients in the no tourniquet group (NQ). Patient demographics, reoperations, and complications were recorded. RLLs were identified on anteroposterior, lateral, and skyline x-rays at 1, 2, and 5 to 8 years postoperatively using the modern knee society radiographic evaluation system. Demographics, reoperations, complications, and RLLs were compared. Age, sex, and body mass index were similar between groups. Mean tourniquet time in TQ was 11 minutes (range, 8 to 25).

RESULTS

The presence of RLLs differed between groups, with 65% of TQ knees having RLLs under any part of the prostheses versus 46% of NQ knees (P < .001). The progression of RLL >2 mm occurred in 26.0% of knees in TQ and 16.7% of knees in NQ (P = .028). There were 13 TKAs that underwent subsequent revision surgery. There was no statistically or clinically significant difference in revision rate between groups (7 revisions in TQ, 6 in NQ, P = .66).

CONCLUSION

Less RLLs were identified in NQ versus TQ. There were no statistically or clinically significant differences in revision rates between the NQ and TQ groups at 5 to 8 years.

The Impact of Perioperative Use of Nonbiologic Disease-Modifying Anti-rheumatic Drugs on Perioperative Blood Loss and Complications in Patients Who Have Rheumatoid Arthritis Undergoing Total Knee Arthroplasty

BACKGROUND

The use of disease-modifying antirheumatic drugs (DMARDs) before total knee arthroplasty (TKA) was associated with increased risk of postoperative periprosthetic joint and wound infections as well as worse platelet function in patients who have knee rheumatoid arthritis (RA). This study investigated the effects of DMARDS on perioperative blood loss, complications, and blood transfusion in patients undergoing TKA for knee RA.

METHODS

We retrospectively enrolled patients undergoing TKA for knee RA at our hospital between 2017 and 2021 who received DMARDs (n = 73) or not (n = 84). Every RA patient was matched with patients who had osteoarthritis (OA) in a ratio of 1:1 or 1:2. Primary outcomes were intraoperative and perioperative blood losses, while secondary outcomes were complications and allogeneic transfusions.

RESULTS

The mean total (804 versus 728 mL (mL), P = .114), mean intraoperative (113 versus 101 mL, P = .488), or hidden blood losses (705 versus 640 mL, P = .340) did not differ statistically between RA patients who received DMARDs versus those who did not. RA patients who received DMARDs showed significantly greater mean total (804 versus 654 mL, P = .001), intraoperative (113 versus 75 mL, P = .002), and hidden blood losses (705 versus 560 mL, P = .016) than OA patients. No statistical differences were found in complications or allogeneic transfusions.

CONCLUSION

Although RA patients experienced greater perioperative blood loss than OA patients, there was no statistical difference in perioperative blood loss, complications, or allogeneic transfusions between RA patients who received DMARDs and those who did not.

Is cement mantle thickness a primary cause of aseptic tibial loosening following primary total knee arthroplasty?

BACKGROUND

Aseptic tibial loosening following primary total knee replacement is one of the leading causes of long-term failure. Cement mantle thickness has been implicated as a source of aseptic tibial loosening. Therefore, the following study was designed to determine (1) what is the cement mantle thickness in patients that develop aseptic tibial loosening, and (2) is there a difference in cement mantle thickness based on the interface of failure?

METHOD

This retrospective cohort included 216 patients revised for aseptic tibial loosening. Patient demographics, operative data, and clinical outcomes were recorded. A preoperative radiographic assessment was performed to determine the interface of failure and the thickness of the cement mantle using the Knee Society Radiographic Evaluation System zones.

RESULTS

The average patient age was 65 years and body mass index was 33.7 kg/m². 203 patients demonstrated radiographic failure at the implant-cement interface and 13 patients demonstrated failure at the cement-bone interface. The average cement mantle thickness of each radiographic zone for the entire cohort on the AP and lateral views was 4.4 and 4.5 mm, respectively. The average cement mantle thickness of patients that developed failure at the implant-cement interface was significantly greater than patients that failed at the cement-bone interface in each radiographic zone (p < 0.001).

CONCLUSIONS

Patients that develop implant loosening at the cement-bone interface were noted to have a significantly decreased cement mantle compared to patients that failed at the implant-cement interface. Methods for decreasing tibial implant loosening should likely focus on improving the fixation at the implant-cement interface.

Trends in Total Knee Arthroplasty Cementing Technique Among Arthroplasty Surgeons-A Survey of the American Association of Hip and Knee Surgeons Members

BACKGROUND

Aseptic loosening persists as one of the leading causes of failure following cemented primary total knee arthroplasty (TKA). Cement technique may impact implant fixation. We hypothesized that there is variability in TKA cement technique among arthroplasty surgeons.

METHODS

A 28-question survey regarding variables in surgeons' preferred TKA cementation technique was distributed to 2,791 current American Association of Hip and Knee Surgeons (AAHKS) members with a response rate of 30.8% (903 respondents). Patterns of responses were analyzed by grouping respondents by their answers to certain questions including cementing technique, tibial cement location, and femoral cement location.

RESULTS

A total of 73.5% reported performing at least 7 of 8 of the highest consensus techniques, including vacuum mixing (79.9%), using two bags (76.1%), tibial implant first (95.2%), single-stage cementing (96.9%), compression of the implants in extension (91.7%), and use of a tourniquet (84.3%). Medium and high viscosity cement was most commonly used (37.9 and 37.8%, respectively). Finger pressurization was most common (76.1%) compared to a gun (29.8%). There were 26.5% of respondents performing 6 or fewer of the most common majority techniques and seemed to perform other less common techniques (eg, use of a single bag of cement, trialing or closure prior to cement curing, and heating to accelerate cement curing). Cement was most commonly applied to the entire bone and implant surface on both the tibia (46.4%) and femur (47.7%), leaving much variation in the remaining cement application location responses.

DISCUSSION

There appears to be variability in cemented TKA technique among arthroplasty surgeons. There were 26.5% of respondents performing less of the majority techniques and also performed other additional low-response rate techniques. Further studies that look at the impacts of variation in techniques on outcomes may be warranted. Our study demonstrates the need for defining best practices for cement technique given the substantial variability identified.

Tourniquet use during primary total knee arthroplasty-a survey of Irish orthopaedic surgeons in 2022

BACKGROUND

Tourniquet use during primary total knee arthroplasty is a debated topic in the literature with no consensus on its optimal use.

AIM

To analyse current tourniquet practice amongst Irish orthopaedic surgeons performing primary total knee arthroplasty surgery. To evaluate if there has been a shift in practice in recent years and to explore potential reasons behind this.

METHODS

An eleven-question online survey was developed using the online platform SurveyMonkey. This was distributed by email to Irish orthopaedic surgeons via the Irish Institute of Trauma and Orthopaedic Surgery.

RESULTS

Fifty responses were included in the final analysis of this study. Eighteen (36%) respondents reported changing their tourniquet use in the past 5 years. Thirty-one (62%) respondents reported inflating the tourniquet for the entire case, with the remaining never applying a tourniquet (n = 6, 12%), applying a tourniquet but not routinely inflating it (n = 3, 6%), or inflating the tourniquet only during cementation (n = 5, 10%). The number of years of experience as a consultant appeared to impact tourniquet use in a bimodal pattern.

CONCLUSION

While the majority of Irish orthopaedic surgeons in this survey inflate a tourniquet for the entire surgical procedure, there is a definite shift towards reduced tourniquet use compared to previous Irish, UK, and American surveys.

No Difference in Revision Rate Between Low Viscosity and High Viscosity Cement Used in Primary Total Knee Arthroplasty

BACKGROUND

Loosening remains one of the most common reasons for revision total knee arthroplasty (TKA). Cement viscosity has a potential role in reducing revision rates for loosening. The aim of this study was to assess the outcome for loosening of the 5 most used cemented knee prostheses by constraint type, based on the cement viscosity type used.

METHODS

There were 214,708 TKA procedures performed between 1999 and 2020 for a diagnosis of osteoarthritis using the 5 most commonly used minimally stabilized, posterior stabilized, and medial pivot design cemented tibial components. Only procedures with a cemented tibial component were included. Outcomes for two different cement viscosities, 140,060 high viscosity and 74,648 low viscosity cement, were compared for each fixation type within each of the three stability groups.

RESULTS

There was no difference in a risk of all-cause revision when high viscosity cement was used compared to low viscosity cement for minimally stabilized prostheses (hazards ratio [HR] 1.07 [95% CI 0.99-1.15], P = .09), posterior stabilized prostheses (HR 1.03 [95% CI 0.95-1.11], P = .53), and medial pivot design prostheses (HR 1.06 [95% CI 0.80-1.41], P = .67). No difference was observed between cement viscosity types for any of the prosthesis constraint types when aseptic loosening was assessed.

CONCLUSIONS

We found no difference in the risk of revision for any reason, or for loosening, with cement viscosity for the most commonly used minimally stabilized, posterior stabilized, and medial pivot TKA. The role of cement viscosity in the risk of TKA revision remains unclear and further research is required.

LEVEL OF EVIDENCE

Level III Retrospective comparative study.

The Effect of Working Time and Application Technique on Cement Penetration into a Tibial Model

Background

Aseptic loosening of the cemented tibial component is a source of failure in total knee arthroplasty. This study examined common techniques for cement application by quantifying depth and volume of penetration into tibia models.

Material and methods

Thirty-six composite tibia models were cemented with a tibial component using 3 application techniques (gun, osteotome, and layered) with either early or late cement working time. Computed tomography and 3D-modeling were used to quantify volume and depth of penetration. Statistical analysis was conducted with analysis of variance with Bonferroni correction and Student’s t-test.

Results

No difference was found in overall volume of penetration between early and late cement application (P = .16). Beneath the baseplate, the layered technique had significantly less penetration and averaged less than 3 mm with early and late cement. The gun technique had the greatest depth of penetration with early cement and averaged greater than 3 mm in all zones regardless of cement working time. The osteotome technique achieved significantly greater depth of penetration around the keel with early and late cement, P < .01.

Conclusions

Using a cement gun ensures adequate penetration beneath the baseplate regardless of cement working time while the osteotome technique is effective to increase penetration around the implant keel. According to our study, applying cement early in its working time may not increase volume of penetration. This study raises concern regarding adequate cement penetration using the layered technique for cementing the tibial component in total knee arthroplasty, and future research is warranted.

Chitranjan S. Ranawat Award: Motion During Total Knee Cementing Significantly Decreases Tibial Implant Fixation Strength

BACKGROUND

Aseptic tibial loosening following primary total knee arthroplasty persists despite technique and device-related advancements. The mechanisms for this mode of failure are not well understood. We hypothesized that knee movement while the cement was curing dispersed lipids at the implant-cement interface and would result in decreased tibial fixation strength.

METHODS

A cadaveric study was performed utilizing 32 torso-to-toe specimens (64 knees). Four contemporary total knee arthroplasty designs were evaluated. Each implant design was randomly assigned to a cadaveric specimen pair with side-to-side randomization. Specimen densitometry was recorded. Each tibial implant was cemented using a standard technique. On one side, the tibial component was held without motion following impaction until complete cement polymerization. The contralateral knee tibial implant was taken through gentle range of motion and stability assessment 7 minutes after cement mixing. Axial tibial pull-out strength and interface failure examination was performed on each specimen.

RESULTS

The average pull-out strength for the no motion cohort (5,462 N) exceeded the motion cohort (4,473 N) (P = .001). The mean pull-out strength between implant designs in the no motion cohort varied significantly (implant A: 7,230 N, B: 5,806 N, C: 5,325 N, D 3,486 N; P = .007). Similarly, the motion cohort inter-implant variance was significant (P ≤ .001). Intra-implant pull-out strength was significantly higher in implant A than D. The average pull-out strength was significantly lower in specimens that failed at the implant-cement interface vs bone failures (4,089 ± 2,158 N vs 5,960 ± 2,010 N, P < .0025).

CONCLUSION

Knee motion during cement polymerization is associated with significant decreases in tibial implant fixational strength. Reduction in implant pull-out strength was identified with each implant design with motion and varied between designs. Across all tested designs, we recommend limiting motion while cementing the tibial implant to improve fixation strength.

The mid-term and long-term effects of tourniquet use in total knee arthroplasty: systematic review

PURPOSE

A tourniquet is routinely used during total knee arthroplasty (TKA) to reduce intra-operative hemorrhage, though surgery without a tourniquet is becoming popular. To address concerns about the effect of blood at cement interfaces on long-term implant stability, we conducted a systematic review among patients undergoing total knee arthroplasty to determine if TKA with a tourniquet, compared to TKA without a tourniquet or with reduced tourniquet duration, is associated with better mid-term and long-term implant stability.

METHODS

A literature search was conducted without language restriction in PubMed, Cochrane database and Web of Science from conception to 17th March, 2021. Prospective cohorts, randomized and observational, that compared tourniquet use with a control group, followed patients for 3 months or more and reported outcomes concerning implant stability, limb function, pain and inflammation. Article selection, quality assessment according to the Revised Cochrane risk assessment scale and Newcastle Ottawa Scale, and data extraction were conducted in duplicate.

PROSPERO

CRD42020179020.

RESULTS

The search yielded 4868 articles, from which 16 randomized controlled trials (RCT) and four prospective cohort studies, evaluating outcomes of 1884 knees, were included. Eleven RCTs were evaluated to be low overall risk of bias, five RCTs had some concerns and four cohort studies were good quality. Few studies showed benefits of tourniquet use in mid-term implant stability (1/6), pain (1/11) and limb inflammation (1/5), and long-term implant stability (1/1). One study reported a significantly improved range of motion (1/14) while another reported significantly reduced quadriceps strength (1/6) in the tourniquet group. The remaining studies reported non-significant effect of tourniquet use.

CONCLUSION

Although few studies indicated benefits of tourniquet use in mid-term pain, limb inflammation, implant loosening and function, and long-term implant loosening, the majority of studies report no significant advantage of tourniquet use in total knee arthroplasty.

The impact of tourniquet on tibial bone cement penetration in different zones in primary total knee arthroplasty: a meta-analysis

Background

Cement mantle penetration and the cement–bone interface strength were critical to a successful primary total knee arthroplasty (TKA). It remained unclear whether decreased blood and fat in the cancellous bone achieved with the use of a tourniquet increases tibial cement mantle penetration in different zones on AP and lateral view in TKA according to criteria defined by the Knee Society Scoring System (KSS). The purpose of this study was to determine whether tourniquet use influences tibial cement mantle penetration in different zones on AP and lateral view in TKA according to KSS.

Methods

We conducted a meta-analysis to identify studies involving the impact of tourniquet use and no tourniquet use on tibial bone cement penetration in primary TKA in electronic databases, including Web of Science, Embase, PubMed, Cochrane Controlled Trials Register, Cochrane Library, Highwire, CBM, VIP, Wanfang database, up to January 2021. Finally, we identified 1231 patients (1231 knees) assessed in twelve studies.

Results

Tourniquet use increases the cumulative cement mantle penetration (P < 0.00001), mean cement mantle penetration (P = 0.004), and cement mantle in zone 3(P < 0.0001) on AP view. However, there were no significant differences in cement mantle in zone 1(P = 0.5), zone 2(P =0 .54), zone 4(P = 0.07) on AP view, and zone 1(P = 0.32), zone 2(P = 0.38) on lateral view between two groups. There were also no significant differences in length of surgery(P = 0.7), change in hemoglobin(P = 0.4), transfusion rates(P = 0.47), and complications such as muscular calf vein thrombosis(P = 0.21), superficial infection (P = 0.72), and deep vein thrombosis (P = 0.66) between two groups.

Conclusion

The application of a tourniquet increases the thickness of the tibial bone cement penetration—the increase in the thickness of bone cement penetration mainly located in zone 3 on the anteroposterior (AP) view.