Soft-tissue damage during total knee arthroplasty: Focus on tourniquet-induced metabolic and ionic muscle impairment

Evaluation of Postoperative Pain When Adding a Tibial Nerve Block to the Femoral Nerve Block for Total Knee Arthroplasty

Background: The aim of this study was to compare the postoperative analgesic efficacy when a tibial nerve block was added to the femoral nerve block for total knee arthroplasty (TKA). Methods: A total of 60 patients were randomly assigned to the experimental group (EG) or the control group (CG) in a 1:1 ratio. The thirty patients who formed the CG underwent an ultrasound-guided femoral nerve block together with neuraxial anaesthesia and the administration of opioids and NSAIDs through an intravenous elastomeric pump for the management of the postoperative pain; the other thirty, who formed the EG, underwent neuraxial anaesthesia together with femoral and tibial nerve blocks. The efficacy of the analgesic effect was evaluated based on the numerical pain rating scale (NPRS) and on the need for analgesic rescue at different time intervals within 48 h after surgery. Results: At 24 h, the mean NPRS score in the EG and CG at rest was 1.50 ± 1.19 and 1.63 ± 1.60 [U = 443.5, p = 0.113], respectively. With joint movement, the mean NPRS score was 2.80 ± 1.49 and 3.57 ± 1.79 [U = 345, p = 0.113], respectively. Ten patients in the EG [33.3%] and 24 in the CG [80%] required rescue analgesia [Phi = 0.471, p < 0.001]. At 48 h, the mean NPRS score in the EG and CG at rest was 0.33 ± 0.60 and 0.43 ± 0.72 [U = 428, p = 0.681], respectively. With movement, the mean NPRS score was 1.03 ± 0.99 in the EG and 1.60 ± 1.07 in the CG [U = 315, p = 0.038]. No patient in the EG group required rescue analgesia, while three patients in the CG [10%] did [Phi = 0.229, p = 0.076]. The mean opioid dosage in the CG was 300 mg, whereas in the EG it was 40 mg ± 62.14 [U < 0.05, p < 0.001]. Conclusions: Adding a tibial nerve block to the femoral nerve block in TKA may achieve the same analgesic efficacy within 48 h after surgery and would reduce the systematic use of opioids.

Randomized Controlled Trial of Irrigation-Coupled Bipolar Electrocautery Versus Tourniquet in Total Knee Arthroplasty

Background

Recovery from total knee arthroplasty remains arduous for some patients, prompting interest in perioperative management. While tourniquet use is not associated with longer-term outcomes, its effect on quadriceps strength in the immediate postoperative window is unknown.

Methods

A single-center, double-blind, randomized controlled trial of 66 patients undergoing primary total knee arthroplasty from 2019 to 2022 was performed to compare the use of an irrigation-coupled bipolar device (ICBD) and no tourniquet (ICBD group, N = 34) to tourniquet use with no ICBD (tourniquet group, N = 32). Groups were similar with respect to age, sex, and obesity. The primary outcome was quadriceps strength at 2 weeks, measured using a handheld dynamometer and standardized to the contralateral side. Knee Injury and Osteoarthritis Outcome Score for Joint Replacement was measured with the difference from baseline serving as a secondary outcome. Comparisons were performed using the Student's t-test.

Results

Only 28 patients, 14 in each group, had primary outcome data. At 2-weeks, quadriceps strength was higher in the ICBD group compared to the tourniquet group (83% vs 70%), though not statistically significant (P = .16). There was no difference between the ICBD and tourniquet groups in Knee Injury and Osteoarthritis Outcome Score for Joint Replacement changed at 2-weeks (13 vs 10, P = .37) or 6-weeks (16 vs 17, P = .76).

Conclusions

Tourniquet use was associated with a small but not statistically significant difference in quadriceps strength at 2 weeks that may justify further study given the loss of power here. There can be limitations to conducting randomized controlled trials that are important for early-career investigators to consider and that were magnified due to COVID-related restrictions in the present study, which we discuss.

Level of Evidence

Level II.

The optimized tourniquet versus no tourniquet in total knee arthroplasty. Analysis of muscle injury, functional recovery, and knee strength

Background

Tourniquet is widely used in total knee replacement surgery because it reduces intraoperative hemorrhage and provides a comfortable surgical area for the surgeon. It's possible that its use could lead to impaired postoperative functional and motor recovery, as well as local and systemic complications. Our goal was to compare the outcomes of total knee replacement without ischemia using an optimized protocol, consisting of tourniquet inflation before skin incision and deflation after cementing, with a pressure of one hundred millimeters above systolic blood pressure and without postoperative articular suction drains.). We believed that tourniquet effectively would result in no additional muscle damage and no functional or knee strength impairment compared to no tourniquet.

Methods

In a prospective and randomized study, 60 patients with osteoarthritis were evaluated for total knee replacement, divided in two groups: 'without tourniquet' and 'optimized tourniquet'. Outcomes were mean creatine phosphokinase levels, Knee Society Score and knee isokinetic strength. Data were considered significant when p < 0.05.

Results

Creatine phosphokinase levels and functional score were similar between groups. There were no differences between groups regarding knee extension strength on the operated limbs, although the knee flexors' peak torque in the operated limb in the optimized tourniquet group was significantly higher at 6 months relative to preoperative and 3 months assessments.

Conclusions

The optimized tourniquet protocol use in total knee replacement combines the benefits of tourniquet use without compromising functional recovery and without additional muscle damage and strength deficits compared to surgery without its use.

Conventional rehabilitation post-TKA achieves better knee flexion with higher resource utilization compared to application-based rehabilitation - a systematic review and meta-analysis

Background

Post-operative physiotherapy is a major component of the effectiveness of knee replacement. Adequate rehabilitation protocols are required for better functional outcomes. With the advent of smartphones and smartwatches, the use of telerehabilitation has increased recently. This study aims to compare tele rehabilitation using various mobile-based applications to conventional rehabilitation protocols.

Methods

From Jan 2000 to Jun 2022, all the RCTs from SCOPUS, EMBASE and PUBMED comparing patient-related outcome measures between the smartphone-based app and conventional rehabilitation protocols were scanned and seven studies meeting the eligibility criteria were included in this systematic review and meta-analysis. The quantitative analysis compared outcomes using the knee injury and osteoarthritis outcome score (KOOS), the knee society function score (KSFS), the active range of motion (AROM), Euro-Qol-5D-5L, and MUA. The qualitative analysis compared VAS, NRS, and Time up and go (TUG).

Results

The study shows statistically significant improvement in traditional rehabilitation over app based on KSFS score (M.D.: 6.05, p = 0.05) and AROM on long-term follow-up (12 months) (M.D.: 2.46, p = 0.02). AROM was insignificant on 3 months or less follow-up. NRS and VAS were found to be statistically better in app-based groups. No statistically significant results were seen on KOOS, Euro-Qol-5D-5L, MUA and TUG. 90 days of readmission and a number of physiotherapy visits were more in conventional groups. No difference was seen in single-leg stance and satisfaction rates.

Conclusions

The present review highlights improved early pain scores and comparable patient-reported outcome analysis at a short-term follow-up period among patients receiving mobile app-based rehabilitation. However, knee range of motion and KSFS score achieved after surgery is analysed to be better with traditional rehabilitation at the one-year end follow-up period.

Hypoxia Resistance Is an Inherent Phenotype of the Mouse Flexor Digitorum Brevis Skeletal Muscle

The various functions of skeletal muscle (movement, respiration, thermogenesis, etc.) require the presence of oxygen (O2). Inadequate O2 bioavailability (ie, hypoxia) is detrimental to muscle function and, in chronic cases, can result in muscle wasting. Current therapeutic interventions have proven largely ineffective to rescue skeletal muscle from hypoxic damage. However, our lab has identified a mammalian skeletal muscle that maintains proper physiological function in an environment depleted of O2. Using mouse models of in vivo hindlimb ischemia and ex vivo anoxia exposure, we observed the preservation of force production in the flexor digitorum brevis (FDB), while in contrast the extensor digitorum longus (EDL) and soleus muscles suffered loss of force output. Unlike other muscles, we found that the FDB phenotype is not dependent on mitochondria, which partially explains the hypoxia resistance. Muscle proteomes were interrogated using a discovery-based approach, which identified significantly greater expression of the transmembrane glucose transporter GLUT1 in the FDB as compared to the EDL and soleus. Through loss-and-gain-of-function approaches, we determined that GLUT1 is necessary for the FDB to survive hypoxia, but overexpression of GLUT1 was insufficient to rescue other skeletal muscles from hypoxic damage. Collectively, the data demonstrate that the FDB is uniquely resistant to hypoxic insults. Defining the mechanisms that explain the phenotype may provide insight towards developing approaches for preventing hypoxia-induced tissue damage.

Clinical efficacy and feasibility of laser correction technology with an ordinary laser pen and surgical instrument box in open-wedge high tibial osteotomy

Background

The clinical outcomes of open-wedge high tibial osteotomy (OWHTO) for medial knee osteoarthritis primarily depend on the corrective precision. The present study aimed to determine the efficacy and feasibility of laser correction technology with an ordinary laser pen and surgical instrument box.

Methods

This prospective and randomized trial included 71 patients randomly divided into laser (n = 36) and traditional groups (n = 35). In the laser group, the hip centre, knee (Fujisawa point), and ankle centre were located preoperatively using the surgical instrument box lid. The leg was aligned with an ordinary laser pen. In the traditional group, the lower limb alignment was corrected by a metal cable. Radiation exposure, operative time, and rate of outliers (lower limb force line does not pass through 62–66% of the lateral tibial plateau) were evaluated. The visual analogue scale (VAS) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores were recorded. After 24 months, the femoral tibial angle (FTA), medial proximal tibial angle (MPTA), and posterior slope angle (PSA), were recorded. The Kaplan-Meier method was used to evaluate the survival time of affected knees, and postoperative complications were recorded.

Results

The radiation exposure, operative time and rate of outliers were lower in the laser correction group (P < 0.05). Six months postoperatively, the VAS and WOMAC scores were significantly improved in both groups (P < 0.001). At 24 months, the FTA, MPTA, and PSA were corrected in both groups (P < 0.001). There were no differences in the postoperative knee survival time from OWHTO to knee arthroplasty between the groups or postoperative complications (P = 0.53; P = 0.61).

Conclusions

Laser correction technology can effectively reduce radiation exposure, the operative time, and the rate of outliers (trial identification number (retrospectively registered): ChiCTR2200060480; date of register: 03/06/2022).

Inflammatory Response in Robotic-Arm-Assisted Versus Conventional Jig-Based TKA and the Correlation with Early Functional Outcomes: Results of a Prospective Randomized Controlled Trial

BACKGROUND

Although the exact etiology of patient dissatisfaction in total knee arthroplasty (TKA) is unclear, the inflammatory response precipitated by surgery may be implicated. Robotic TKA has been shown to result in reduced bone and soft-tissue trauma. The objectives of this study were to compare the inflammatory response in conventional jig-based TKA versus robotic-arm-assisted TKA and to examine the relationship with early functional outcomes.

METHODS

This prospective randomized controlled trial included 15 patients with symptomatic knee osteoarthritis undergoing conventional TKA and 15 undergoing robotic-arm-assisted TKA. Blood samples were collected for up to 28 days postoperatively, and predefined markers of systemic inflammation were measured in serum. The local inflammatory response was assessed by analyzing samples from the intra-articular drain fluid at 6 and 24 hours. Relationships with early functional outcomes were evaluated using the Spearman rank correlation coefficient.

RESULTS

Patients in the robotic TKA group demonstrated lower levels of interleukin (IL)-6 in the drain fluid at 6 hours (798.54 pg/mL versus 5,699.2 pg/mL, p = 0.026) and 24 hours and IL-8 at 6 hours. Robotic TKA was associated with lower pain scores on postoperative days 1, 2, and 7. Patient-reported outcome measures were comparable between the 2 groups at 2 years. Significant correlations were observed between all serum markers except IL-1b and self-reported pain on postoperative day 7; between drain IL-8 levels and pain on postoperative days 1 (r = 0.458), 2, and 7; and between drain IL-6, IL-8, and tumor necrosis factor-alpha levels at 6 hours and knee flexion or extension.

CONCLUSIONS

Robotic-arm-assisted TKA was associated with a reduction in the early postoperative local inflammatory response. We also found a moderate relationship between the inflammatory responses and self-reported pain, knee flexion, and knee extension. Further validation of these findings on a larger scale and using longer-term outcomes will be key to developing the optimal TKA procedure.

LEVEL OF EVIDENCE

Therapeutic Level I . See Instructions for Authors for a complete description of levels of evidence.

Impact of a Six-Week Prehabilitation With Blood-Flow Restriction Training on Pre- and Postoperative Skeletal Muscle Mass and Strength in Patients Receiving Primary Total Knee Arthroplasty

Introduction: Total Knee Arthroplasty (TKA) is one of the most successful interventions in gonarthrosis, however the operation is leading to muscle atrophy and long-term muscular deficits. To enhance rehabilitation after TKA, exercise programs try to improve muscle function preoperatively, called prehabilitation. Blood-Flow-Restriction Exercises (BFRE) is a training method which is characterized by using tourniquets to reduce arterial and occlude venous blood flow simultaneously during the exercise to increase metabolic stress. The present study aimed to evaluate the effects of a 6-week prehabilitation with BFR on pre- and postoperative muscle mass, strength, and quality of life (QoL).

Methods: 30 patients with end-stage gonarthrosis participated in this study. Patients were randomized into one of three groups: 1) Control-Group (CON): Standard clinical approach without prehabilitation. 2) Active-Control-Group (AC): Participation in a prehabilitation with sham-BFR. 3) BFR-Group (BFR): Participation in a prehabilitation with BFR. The prehabilitation protocol consist of a cycling-ergometer-based training performed twice per week over 6 weeks. During exercise, BFR was applied periodically three times per leg with a pressure of 40% of the individual-limb-occlusion-pressure. Measurement time points were six- (baseline), 3-weeks and 5-days before the surgery (Pre-OP), as well as three- and 6-months postoperatively. Outcome measures were muscular strength of the thigh muscles, thigh circumference as well as QoL and functional activity, examined by 6-min walking- and chair rising test.

Results: Both training groups indicated significantly improved leg muscle strength following the prehabilitation period with a superior effect for the BFR-group (BFR: ∼170% vs. AC: ∼91%, p < 0.05). No significant changes in leg strength occurred in the CON (∼3%, p = 0.100). Further, patients in BFR-group indicated significantly improved skeletal muscle mass assessed by femoral circumference following prehabilitation period (∼7%, p < 0.05), while no significant changes occurred in the CON (−1.14%, p = 0.131) and AC-group (∼3%, p = 0.078). At 3-months Post-OP, the CON and BFR-group revealed a significant decrease in femoral circumference compared to the Pre-OP (CON: ∼3%, BFR: ∼4%; p < 0.05), but BFR-group remained above the baseline level (∼3%, p < 0.05). No significant change in femoral circumference was found for AC-group (∼2%, p = 0.078). In addition, the prehabilitation with BFR provided notably improved Knee Injury and Osteoarthritis Outcome Scores (KOOS) especially in pain perception with significant higher effect compared to other groups (CON: −2%, AC: 13%, BFR: 41%; p < 0.05). In long-term rehabilitation after 6-months, all groups showed significantly improved KOOS scores in all dimensions (CON: ∼110%, AC: ∼132%, BFR: ∼225%; p < 0.01), and functional examinations (CON: ∼26%, AC: ∼16%, BFR: ∼53%; p < 0.01).

Conclusion: The present findings show that BFR-prehabilitation induce significant improvements in muscle function and QoL before TKA surgery. In addition, the supporting effect of prehabilitation on postoperative regeneration and QoL should be highlighted, illustrating prolonged beneficial effects of BFR on muscular and functional performance in a “better in, better out”-manner.

Development and Characterization of a Self-Tightening Tourniquet System

Uncontrolled hemorrhage remains a leading cause of death in both emergency and military medicine. Tourniquets are essential to stopping hemorrhage in these scenarios, but they suffer from subjective, inconsistent application. Here, we demonstrate how tourniquet application can be automated using sensors and computer algorithms. The auto-tourniquet self-tightens until blood pressure oscillations are no longer registered by the pressure sensor connected to the pneumatic pressure cuff. The auto-tourniquet's performance in stopping the bleed was comparable to manual tourniquet application, but the time required to fully occlude the bleed was longer. Application of the tourniquet was significantly smoother, and less variable, for the automatic tourniquet compared to manual tourniquet application. This proof-of-concept study highlights how automated tourniquets can be integrated with sensors to provide a much more consistent application and use compared to manual application, even in controlled, low stress testing conditions. Future work will investigate different sensors and tourniquets to improve the application time and repeatability.

Supervisory Algorithm for Autonomous Hemodynamic Management Systems

Future military conflicts will require new solutions to manage combat casualties. The use of automated medical systems can potentially address this need by streamlining and augmenting the delivery of medical care in both emergency and combat trauma environments. However, in many situations, these systems may need to operate in conjunction with other autonomous and semi-autonomous devices. Management of complex patients may require multiple automated systems operating simultaneously and potentially competing with each other. Supervisory controllers capable of harmonizing multiple closed-loop systems are thus essential before multiple automated medical systems can be deployed in managing complex medical situations. The objective for this study was to develop a Supervisory Algorithm for Casualty Management (SACM) that manages decisions and interplay between two automated systems designed for management of hemorrhage control and resuscitation: an automatic extremity tourniquet system and an adaptive resuscitation controller. SACM monitors the required physiological inputs for both systems and synchronizes each respective system as needed. We present a series of trauma experiments carried out in a physiologically relevant benchtop circulatory system in which SACM must recognize extremity or internal hemorrhage, activate the corresponding algorithm to apply a tourniquet, and then resuscitate back to the target pressure setpoint. SACM continues monitoring after the initial stabilization so that additional medical changes can be quickly identified and addressed, essential to extending automation algorithms past initial trauma resuscitation into extended monitoring. Overall, SACM is an important step in transitioning automated medical systems into emergency and combat trauma situations. Future work will address further interplay between these systems and integrate additional medical systems.

Therapeutic effects of masitinib on abnormal mechanoreception in a mouse model of tourniquet-induced extremity ischemia-reperfusion

Tourniquets are widely used to stop extremity hemorrhage, but their use and subsequent release can result in nerve damage and degeneration, leading to neurological deficits. Increasing evidence has suggested a pivotal role of inflammation in nerve damage and abnormal mechanoreception. In this study, we investigated the therapeutic effects of masitinib (Mas), an anti-neuroinflammatory drug, on the mechanoreception of sensory neurons in a mouse model of tourniquet-induced hind paw ischemia-reperfusion (tourniquet/IR). C57BL/6 mice were subjected to 3 h of ischemia by placing a rubber band at the ankle joint and evaluated for subsequent reperfusion injury on day 1, 3, 7, 14, and 28 based on the experiments. Treatment with Mas (28 mg/kg/day, i.p.) began on the day of IR induction and lasted for 1, 3, 7, 14, or 28 days. Tourniquet/IR caused sensory nerve denervation in the skin of paw pads and abolished the hind paw mechanoreception to mechanical stimulation during the first 3 days of reperfusion. Sensory nerves gradually reinnervated in the skin of paw pads and allodynia began to appear on day 7. The maximum reaction occurred on day 14 and was maintained throughout the study period. Treatment with Mas mitigated nerve damage and improved hind paw mechanoreception to mechanical stimulation by decreasing the production of reactive oxygen species (ROS) during the early stages of tourniquet/IR. Mas also alleviated allodynia and decreased inflammatory cytokines (IL-1β and TNFα) in the skin of paw pads from days 7-28. Our data suggest that treatment with Mas significantly ameliorated paw numbness and allodynia in mouse hind paw tourniquet/IR.

Enhanced recovery after surgery protocols in total knee arthroplasty via midvastus approach: a randomized controlled trial

BACKGROUND

Enhanced recovery after surgery (ERAS) protocols were rapidly adopted in many surgeries such as fast-track arthroplasty. The study aimed to investigate the impact of ERAS protocols on the clinical effect of total knee arthroplasty (TKA) via the midvastus approach.

METHODS

A total of 69 patients who underwent primary unilateral TKA via the midvastus approach from October 2018 to June 2019 were enrolled and randomly divided into two groups: ERAS group and Control group. The ERAS protocols were adopted for the ERAS group and consisted of pure juice drinking 2 h before the surgery, optimization of the preoperative anesthesia plan, phased use of tourniquets, and the use of tranexamic acid as well as a drug cocktail. The operative time, first postoperative walking time, first straight leg elevation time, postoperative hospitalization time, visual analogue scale score (VAS score), Hospital for Special Surgery score (HSS score), conventional Knee Society score (KSS), and knee range of motion (ROM) were used to assess the clinical effects in the two groups. All the included patients were followed up for 12 months.

RESULTS

There were no significant differences in the basic demographic information and operation time between the ERAS and Control groups (P > 0.05). The first postoperative walking time (2.11 ± 0.11 h) and first postoperative straight leg elevation time (6.14 ± 1.73 h) in the ERAS group were significantly earlier than those in the Control group (P < 0.001) and the postoperative hospitalization time was significantly shorter (3.11 ± 0.32 days). The postoperative mean VAS scores in both groups were significantly reduced compared with those before surgery (P < 0.001). The VAS scores for the ERAS group were significantly lower than those for the Control group at 1, 2, and 7 days after surgery (P < 0.001). The mean HSS scores, KSS, and knee ROM were significantly increased in both the ERAS and Control groups at 1, 3, 6, and 12 months after surgery (P < 0.001). In addition, the HSS scores, KSS, and knee ROM in the ERAS group were significantly higher than those in the Control group at 1 month after surgery (P < 0.001).

CONCLUSIONS

ERAS protocols improved the clinical effects of TKA via the midvastus approach, facilitating early out-of-bed activity and comfortable postoperative rehabilitation exercise, and further increasing patient satisfaction.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT04873544 .

Supercapsular percutaneously-assisted total hip (SuperPath) versus mini-incision posterolateral total hip arthroplasty for hip osteoarthritis: a prospective randomized controlled trial

Background

Supercapsular percutaneously-assisted total hip (SuperPath) arthroplasty has been proposed to be minimally invasive and tissue sparing, with possible superior postoperative outcomes compared with conventional approaches for total hip arthroplasty (THA). However, previous studies have underlined the shortcomings of conventional THA approaches, including higher dislocation, more blood loss, longer incisions, more tissue damage, and delayed postoperative rehabilitation. In the present study, we compared the short-term outcomes of unilateral THA with those of SuperPath and the mini-incision posterolateral approach (PLA) for hip osteoarthritis (OA).

Methods

Patients with unilateral hip OA were prospectively recruited and underwent either SuperPath (SuperPath group) or mini-incision PLA THA (PLA group). Perioperative status [operative time, incision length, intraoperative blood loss, soft tissue damage, and length of hospital stay (LOS)], and postoperative function outcomes, including range of motion (ROM), pain visual analog scale (VAS), and Harris Hip Score (HHS), were evaluated and compared between the groups at scheduled time points within 12 months postoperatively.

Results

Compared with the PLA group, the SuperPath group yielded a significantly shorter incision length (7.83 vs. 12.45 cm, P<0.001), longer operative time (102.72 vs. 66.22 min, P<0.001), more blood loss (1,007.38 vs. 844.55 mL, P=0.005), and more soft tissue damage (creatine kinase: 1,056.05 vs. 821.50 U/L, P=0.006) on postoperative day 3. The SuperPath group also showed deficient acetabular cup positioning (abduction angle: 36.94° vs. 42.66°, P=0.004) and a greater decrease in ROM (flexion: 107.66° vs. 114.44°, P=0.004; 109.83° vs. 116.11°, P=0.002; 111.66° vs. 118.88°, P<0.001) on postoperative days 1, 3, and 14, as well as severe early-term pain symptoms (pain VAS on postoperative day 3: 7.05 vs. 6.55, P=0.041). However, the LOS, C-reactive protein levels, erythrocyte sedimentation rate (within 2 weeks postoperatively), and HHS were comparable between the groups during the 12 months postoperatively.

Conclusions

SuperPath may be a promising, minimally invasive technique for the treatment of OA in the future. Further investigation is necessary to evidence the possible superiority of SuperPath over other conventional mini-incision THA approaches.

Impact of Cytokines and Phosphoproteins in Response to Chronic Joint Infection

The early cellular response to infection has been investigated extensively, generating valuable information regarding the mediators of acute infection response. Various cytokines have been highlighted for their critical roles, and the actions of these cytokines are related to intracellular phosphorylation changes to promote infection resolution. However, the development of chronic infections has not been thoroughly investigated. While it is known that wound healing processes are disrupted, the interactions of cytokines and phosphoproteins that contribute to this dysregulation are not well understood. To investigate these relationships, this study used a network centrality approach to assess the impact of individual cytokines and phosphoproteins during chronic inflammation and infection. Tissues were taken from patients undergoing total knee arthroplasty (TKA) and total knee revision (TKR) procedures across two tissue depths to understand which proteins are contributing most to the dysregulation observed at the joint. Notably, p-c-Jun, p-CREB, p-BAD, IL-10, IL-12p70, IL-13, and IFN-γ contributed highly to the network of proteins involved in aseptic inflammation caused by implants. Similarly, p-PTEN, IL-4, IL-10, IL-13, IFN-γ, and TNF-α appear to be central to signaling disruptions observed in septic joints. Ultimately, the network centrality approach provided insight into the altered tissue responses observed in chronic inflammation and infection.

The learning curve of patient-specific unikondylar arthroplasty may be advantageous to off-the-shelf implants: A preliminary study

Introduction

Introducing a new arthroplasty system into clinical routine is challenging and could have an effect on early results. Since UKA are known to have failure mechanisms related to technical factors, reliable results and easy adoption are ideal. The question remains whether there are differences in objective procedure parameters in the early learning curve of different UKA systems.

Methods

two different UKA implants (Biomet Oxford[BO] followed by Conformis iuni[CI]) were introduced consecutively into clinical routine. We retrospectively analyzed the first 20 cases of each implant for one arthroplasty surgeon regarding operating time, correction of the mechanical axis, learning curve parameters, and revision rate of implants for 1.5 years postoperatively.

Results

Operating time (BO:98.3 ± 26.3min, CI:83.85 ± 21.8min (p < 0.078)), and tourniquet time differed in favor of the CI implant (BO:97.5 ± 29.5min; CI:73.5 ± 33.2 min; p < 0.017)). Mechanical alignment was restored in boths (preop:BO:mean 2.9°varus, CI:2.7°varus, postop:BOmean1.3°varus, CI:1°varus), while one BO patient and two CI patients were overcorrected. Operating time decreased from the first five implants to implants 16-20 for CI (95.2 ± 18.5min to 69 ± 21.5min, p < 0.076) and BO (130.6 ± 27.6min to 78 ± 17.3min, p < 0.009). Within 18 months of follow-up, 2 BO and 1 CI implants were revised.

Conclusion

The introduction of an UKA implant was associated with longer surgery in both implants. Procedure time seems to differ between implants, while a learning curve was observed regarding instrumentation. CI implants seem to be reliable and adaptable in a medium-volume practice. The early results of this retrospective single-surgeon study were in favor of the individualized implant. Certainly, further studies encompassing larger cohorts with various implants are needed.

Supercapsular percutaneously-assisted total hip (SuperPath) versus posterolateral total hip arthroplasty in bilateral osteonecrosis of the femoral head: a pilot clinical trial

Background

The supercapsular percutaneously-assisted total hip arthroplasty (SuperPath) was proposed to be minimally invasive and tissue sparing with possible superior postoperative outcomes to traditional approaches of total hip arthroplasty (THA). Here, we compared the short-term outcomes of staged THA with the SuperPath or through posterolateral approach (PLA) for bilateral osteonecrosis of the femoral head (ONFH).

Methods

Patients with bilateral late-stage ONFH were prospectively recruited from our department from March 2017 to March 2018. Staged bilateral THAs with one side SuperPath and the other side PLA were performed consecutively in the same patients with right and left hips alternating within approaches. The average time interval between the staged THAs was 3 months. Perioperative status (operation time, incision length, intraoperative blood loss, soft tissue damage, and length of hospital stay) and postoperative function (range of motion, pain, and hip function) were recorded and compared between the SuperPath and PLA approaches within 12-month postoperatively.

Results

Four male patients (age, 51.00 ± 4.54; BMI, 21.49 ± 1.73) with bilateral alcohol-induced ONFH (Ficat III/IV) were followed up over 12 months postoperatively. Compared with the PLA, the SuperPath yielded shorter incision length (7.62 vs. 11.12 cm), longer operation time (103.25 vs. 66.50 min), more blood loss (1108.50 vs. 843.50 ml), deficient abduction angle of the acetabular cup (38.75° vs. 44.50°), and inferior early-term hip function (Harris hip score, 72.50 vs. 83.25) at 12-month postoperatively. Soft tissue damage, length of hospital stay, postoperative pain, postoperative range of motion, and 12-month patient satisfaction were comparable between both approaches.

Conclusion

The SuperPath may be a minimally invasive technique but the present study shows less favorable short-term outcomes than PLA for total hip arthroplasty in osteonecrosis of the femoral head. More investigations are required to provide convincing favorable evidences of the SuperPath over other traditional THA approaches.

Trial registration information

The trial was retrospectively registered in https://www.researchregistry.com (No. Researchregistry4993) on July 04, 2019. The first participant was enrolled on March 13, 2017.

[Effect of pneumatic tourniquet on perioperative blood loss in total knee arthroplasty]

Objective

To evaluate the effect of pneumatic tourniquet on perioperative period of total knee arthroplasty (TKA).

Methods

The perioperative period data of 116 patients over 60 years old with severe knee osteoarthritis treated with TKA between January 2018 and January 2019 were retrospectively analyzed. According to whether pneumatic tourniquet was used during operation, the patients were divided into trial group (49 cases, pneumatic tourniquet was not used during operation) and control group (67 cases, pneumatic tourniquet was used during operation). There was no significant difference in gender, age, body mass index, lesion side, disease duration, and preoperative hemoglobin between the two groups ( P>0.05). The operation time, actual total blood loss, overt blood loss, hidden blood loss, and percentage of hidden blood loss, knee swelling at 3 days after operation, and range of motion of knee at 2 weeks after operation were recorded and compared between the two groups.

Results

The operation time of the trial group was significantly longer than that of the control group ( t=14.013, P=0.000). The actual total blood loss, hidden blood loss, and percentage of hidden blood loss in the trial group were significantly lower than those in the control group ( P<0.05); there was no significant difference in the overt blood loss between the two groups ( t=-1.293, P=0.200). The knee swelling degree in the trial group was significantly slighter than that in the control group at 3 days after operation, and the range of motion of knee in the trial group was significantly better than that in the control group at 2 weeks after operation ( P<0.05).

Conclusion

Pneumatic tourniquet can reduce the operation time of TKA significantly. However, it may increase the hidden blood loss and knee swelling, and negatively impact the recovery of knee function in the early postoperative stage of TKA.

Protocol for a single-centre, parallel-arm, double-blind randomised trial evaluating the effects of tourniquet use in total knee arthroplasty on intra-operative and post-operative outcomes

BACKGROUND

Tourniquet use during total knee replacement is common, yet uncertainty exists regarding its benefits and harms. The primary aim of the current study is to investigate whether tourniquet use during total knee replacement leads to greater reduction in quadriceps strength than non-tourniquet use at three months post-surgery. Secondary aims include investigating the effects of tourniquet use on: quadriceps strength at day 2 and 5, and 12 months post-surgery; pain and analgesia requirements; self-reported physical function and quality of life; blood loss and replacement; surgeon satisfaction with the intra-operative visual field; operation and anaesthetic time; complications; cement mantle quality; patient satisfaction; and hospital length of stay.

METHODS

The study is a single centre, parallel-arm, double-blind (participant and assessor), randomised trial with 1:1 random allocation. Participants will be undergo total knee replacement with or without tourniquet. Linear mixed models will be used for group comparisons of continuous outcomes available at multiple timepoints. Other continuous outcomes that are assessed at baseline and once/twice at follow-up will be analysed using linear regression. Categorical outcomes will be analysed using logistic regression models.

DISCUSSION

This study will provide high-quality evidence regarding the effects of tourniquet use during total knee replacement, which can be used to inform surgeon decision-making.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry ACTRN12618000425291 . Retrospectively registered 23 March 2018.

Ischemic Preconditioning Blunts Muscle Damage Responses Induced by Eccentric Exercise

PURPOSE

Ischemic preconditioning (IPC) is known to reduce muscle damage induced by ischemia and reperfusion injury during surgery. Because of similarities between the pathophysiological formation of ischemia and reperfusion injury and eccentric exercise-induced muscle damage (EIMD), as characterized by an intracellular accumulation of Ca, an increased production of reactive oxygen species, and increased proinflammatory signaling, the purpose of the present study was to investigate whether IPC performed before eccentric exercise may also protect against EIMD.

METHODS

Nineteen healthy men were matched to an eccentric-only (ECC; n = 9) or eccentric proceeded by IPC group (IPC + ECC; n = 10). The exercise protocol consisted of bilateral biceps curls (3 × 10 repetitions at 80% of the concentric one-repetition maximum). In IPC + ECC, IPC was applied bilaterally at the upper arms by a tourniquet (200 mm Hg) immediately before the exercise (3 × 5 min of occlusion, separated by 5 min of reperfusion). Creatine kinase (CK), arm circumference, subjective pain (visual analog scale score), and radial displacement (tensiomyography, maximal radial displacement) were assessed before IPC, preexercise, postexercise, and 20 min, 2 h, 24 h, 48 h, and 72 h postexercise.

RESULTS

CK differed from baseline only in ECC at 48 h (P < 0.001) and 72 h (P < 0.001) postexercise. After 24, 48, and 72 h, CK was increased in ECC compared with IPC + ECC (between groups: 24 h, P = 0.004; 48 h, P < 0.001; 72 h, P < 0.001). The visual analog scale score was significantly higher in ECC at 24-72 h postexercise when compared with IPC + ECC (between groups: all P values < 0.001). The maximal radial displacement was decreased on all postexercise days in ECC (all P values < 0.001) but remained statistically unchanged in IPC + ECC (between groups: P < 0.01).

CONCLUSIONS

These findings indicate that IPC performed before a bout of eccentric exercise of the elbow flexors blunts EIMD and exercise-induced pain while maintaining the contractile properties of the muscle.