post-TKA Pain Research Articles

A biopsychosocial approach to phenotyping people with knee osteoarthritis awaiting total knee arthroplasty: A secondary cohort analysis

BackgroundPrevious research showed chronic post-total knee arthroplasty (TKA) pain in 20% of people with knee osteoarthritis (KOA). Various preoperative biopsychosocial-related factors have been described, but phenotyping people with KOA awaiting TKA based on these factors is still lacking. This could be relevant to understanding differences in TKA surgery responses. ObjectiveTo identify phenotypes in people with KOA awaiting TKA and differences in post-TKA pain based on preoperative biopsychosocial factors. MethodsPeople with KOA awaiting TKA in 4 hospitals in Belgium and the Netherlands were included. A cross-sectional latent profile analysis was conducted on structural, metabolic, functional, pain-related, psychological and social variables. Concurrent validity was tested using 3-step multinomial logistic regression. The difference in one-year post-TKA pain was examined with linear mixed model analysis. ResultsTwo hundred and seventeen participants were included in the latent profile analysis with a mean (SD) age of 65.5 (7.7) years, including 109 women. A model with 2 phenotypes differed in 14 out of 21 variables. Participants with phenotype 2 (28%) had a higher body mass index (BMI), higher chance of having less structural damage (KOA grade), lower mean quadriceps strength and physical function (Knee Society Scoring System functional and 30-second chair stand test), higher pain intensity, number of pain locations, and indices of central sensitisation (temporal summation, central sensitisation inventory score, and lower pressure pain thresholds), higher pain catastrophising, anxiety and depression, and higher post-TKA pain intensity compared to phenotype 1 (72%). Concurrent validity was confirmed in 3 out of 4 variables. ConclusionsPhenotype 2 (28%) with nociplastic pain characteristics in combination with worse psychological factors, BMI, functional and structural factors, and phenotype 1 (72%) not representing these characteristics were identified. Phenotype 2 had worse pain intensity scores after TKA compared to phenotype 1. Attention to the characteristics of phenotype 2 is warranted concerning post-TKA pain. Database registrationThe protocol is registered at ClinicalTrials.gov (NCT05380648).

Genicular nerve radiofrequency ablation practice patterns: A survey study of the International Pain and Spine Interventional Society

IntroductionChronic knee pain often results from degenerative conditions such as knee osteoarthritis (OA) and can worsen after surgical interventions like total knee arthroplasty (TKA). Knee OA affects approximately 86 million individuals globally, leading to decreased function, mobility limitations, and disability. While TKA is a common surgical treatment for refractory knee OA, though up to 20 % of patients experience chronic post-operative knee pain worse than their pre-operative pain. Genicular nerve radiofrequency ablation (GnRFA) has emerged as a promising intervention for knee OA pain unresponsive to conservative management and for chronic post-TKA pain. GnRFA is an evidence-based technique supported by multiple prospective cohort studies and randomized controlled trials (RCTs). However, practice patterns and GnRFA techniques vary, and no peer-reviewed publication has yet quantified these variations in real-world clinical practice. ObjectiveThis study aims to understand the practice patterns of interventional pain physicians regarding patient selection, use of prognostic blocks, imaging, nerve targets, GnRFA types, and GnRFA techniques in treating knee pain secondary to OA or persistent post-TKA pain. MethodsAn anonymous 29-question survey was distributed via electronic mail to members of the International Pain and Spine Intervention Society (IPSIS) from January 16, 2024, to February 29, 2024. The survey assessed practice patterns related to patient selection, prognostic block use, and GnRFA techniques. Data were collected and stored using REDCap software, with descriptive statistics calculated. ResultsA total of 150 completed surveys were analyzed, representing a completion rate of 2.0 % of surveys sent, 3.5 % of emails opened, and 56.8 % of those who clicked on the survey link. Respondents generally use common selection protocols regarding OA grade (Kelgren-Lawrence 3 and 4), duration of failed conservative care (3–6 months), a single anesthetic block paradigm, and use of fluoroscopic guidance for the GnRFA procedure. More variability was reported between respondents regarding the volume of anesthetic used during prognostic blocks, the threshold to consider a prognostic block “positive,” the technology used, and nerves targeted during the GnRFA procedure. ConclusionThe study provides valuable insights into the current practice patterns of GnRFA among interventional pain physicians. While there is consensus on some aspects of patient selection and procedural techniques, significant variability exists in prognostic block protocols and nerve targets for GnRFA. These findings highlight the need for further research to explore the long-term efficacy and safety of GnRFA and to standardize techniques and protocols across different practice settings, ultimately improving patient outcomes and quality of life. The low response rate may limit generalizability, and the survey did not include data on active tip sizes used for ablation or whether other procedures should be exhausted before resorting to GnRFA. Additionally, a survey to IPSIS membership only may not fully represent a diverse cohort of pain management specialists, potentially introducing sampling bias. Future studies should include members from a broader range of professional organizations to enhance representativeness.

Nalbuphine versus morphine: an adjuvant to spinal anesthesia for controlling pain after total knee arthroplasty: a propensity score-matched analysis.

Nalbuphine, a synthetic k-agonist and µ-antagonist, provides efficient pain relief while reducing opioid-related adverse effects. This study aims to compare the efficacy of intrathecal nalbuphine (ITN) with intrathecal morphine (ITM) for post-TKA pain. A retrospective cohort analysis of 131 patients who underwent TKA with spinal anesthesia (SA), a single shot of adductor canal block, and periarticular injections was conducted. The patients were divided into 2 groups, Group N received 0.8mg nalbuphine, and Group M received 0.2mg morphine as an adjuvant to SA. Propensity-score matching was employed to compare the visual analog scales (VAS) of postoperative pain intensity, cumulative morphine use (CMU), maximum knee flexion angle, straight leg raise (SLR) ability, incidence of postoperative nausea and vomiting (PONV), and length of hospital stay (LHS). The mean VAS of group M were significantly lower than group N at 6, 12, 18, and 24h (P < 0.01). Group M had lower CMU than group N at 24h (P < 0.01) and 48h (P < 0.01), while there was no significant difference between groups in terms of knee flexion angle and SLR at any time point. Additionally, 29.3 and 57.9% of patients in group N and M experienced PONV, respectively (p = 0.04), and group N had significantly shorter LHS compared to group M (P < 0.001). Although, intrathecal morphine (ITM) still provides better pain control particularly in the first 24h, patients who received intrathecal nalbuphine (ITN) had significantly fewer incidence of PONV, and shorter LHS.

Psychosocial Interventions to Reduce Post operative Pain in Total Knee Arthroplasty: A Systematic Review

Background: Total knee arthroplasty (TKA) is a common surgical remedy for patients with end-stage osteoarthritis. Although TKA is generally effective, a significant number of patients experience chronic post-surgical pain. Psychosocial interventions have increasingly become an area of interest in pain management following surgical procedures. Purpose: We aimed to evaluate the impact of pre-operative, peri-operative, and post-operative psychosocial interventions on reducing the likelihood of developing chronic pain after TKA. Methods: We performed a systematic review following the Cochrane guidelines and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist. A comprehensive search strategy was employed using PubMed, Embase, and Cochrane Central Register of Controlled Trials. Inclusion criteria were (1) patients undergoing; (2) pain outcome assessed ≥1 month post-operatively; (3) prospective and longitudinal study design (eg, randomized controlled trial, experimental non-randomized trial, cohort, case-control studies with measurement of exposure prior to outcome); (4) English language; and (5) psychosocial intervention (cognitive-behavioral, biopsychosocial, dialectical behavioral, psychoeducation, mindfulness, meditation, psychotherapy, relaxation, mind-body therapies, hypnosis). Exclusion criteria were non-primary literature (eg, review articles), non–peer-reviewed studies, and conference proceedings. The methodological quality of included studies was assessed using Cochrane’s tool for Risk of Bias 2 (RoB 2), the methodological index for non-randomized studies (MINORS), and the Risk of Bias in Non-randomized Studies of Interventions (ROBINS-I). Results: Of 4297 studies reviewed with title and abstract, 4160 were excluded. Of the remaining 137 studies that underwent full-text review, 122 were excluded using the same inclusion and exclusion criteria, and 15 studies were included. Our review indicates a variable but positive impact of psychosocial interventions, such as pre-operative education, relaxation techniques, and cognitive-behavioral therapy, on post-TKA pain. Of the 15 included studies, 9 studies found that psychosocial interventions reduced post-TKA pain. Our review also suggests that cognitive-behavioral therapy may aid in reducing kinesiophobia, pain catastrophizing, and knee pain intensity. For the 12 randomized studies, the risk of bias was deemed “high” concerns for 3 studies, “some” concerns for 5 studies, and “low” concerns for 4 studies. For the 3 non-randomized studies, the risk of bias was deemed “moderate” due to confounding bias. Conclusions: This systematic review of level-I and level-II studies found that the integration of psychosocial interventions into care protocols for TKA offers benefits including improved patient satisfaction and quality of life and reduced health care costs. Limitations include heterogeneity in intervention types and outcomes measured and the varying levels of risk of bias across studies, which may affect the generalizability of the findings. The findings support a broader adoption of holistic, patient-centered approaches in pain management after TKA, emphasizing the importance of psychological well-being for optimal patient outcomes. However, the evidence is limited and constitutes a strong impetus for the further study of these interventions.

Preoperative glycaemic control, number of pain locations, structural knee damage, self-reported central sensitisation, satisfactionand personal control are predictive of 1-year postoperative pain, and change in pain from pre- to 1-year posttotal knee arthroplasty.

The aim of this study was to identify preoperative predictors for 1-year posttotal knee arthroplasty (TKA) pain and pre- to post-TKA pain difference in knee osteoarthritis (KOA) patients. From March 2018 to July 2023, this prospective longitudinal cohort study enrolled KOA patients awaiting TKA from four hospitals in Belgium and the Netherlands. Different biopsychosocial predictors were assessed preoperatively by questionnaires and physical examinations (input variables). The Knee injury and Osteoarthritis Outcome Score (KOOS) subscale pain was used to measure pain intensity. The absolute KOOS subscale pain score 1-year post-TKA and the difference score (ΔKOOS = 1-year postoperative - preoperative) were used as primary outcome measures (output variables). Two multivariable linear regression analyses were performed. Two hundred and twenty-threeparticipants were included after multiple imputation. Worse absolute KOOS subscale pain scores 1-year post-TKA and negative or closer to zero ΔKOOS subscale pain scores were predicted by self-reported central sensitisation, lower KOA grade and preoperative satisfaction,and higher glycated haemoglobin, number of pain locationsand personal control (adjusted R2 = 0.25). Additional predictors of negative or closer to zero ΔKOOS subscale pain scores were being self-employed, higher preoperative pain and function (adjusted R2 = 0.37). This study reports different biopsychosocial predictors for both outcomes that have filtered out other potential predictors and providevalue for future studies on developing risk assessment tools for the prediction of chronic TKA pain. The protocol is registered at clinicaltrials.gov (NCT05380648) on 13 May 2022. Level II.

Moderating effects of preoperative knee pain and pain catastrophizing on the relation between COMT rs4680 genotypes and chronic postsurgical pain in total knee arthroplasty patients

BackgroundThe Catechol-O-methyltransferase (COMT) gene, responsible for encoding an enzyme crucial in the metabolism of catecholamines, is known to play a significant role in pain perception. Polymorphisms within this gene, particularly the COMT rs4680 genotypes, have been linked to various acute pain phenotypes. This prospective cohort study examines interactions among the genetic polymorphism COMT rs4680 genotypes, preoperative knee pain, and pain catastrophizing in chronic postsurgical pain (CPSP) at 3, 6, and 12 months post-total knee arthroplasty (TKA). Study designA total of 280 patients undergoing primary unilateral TKA participated, sharing demographic details, preoperative knee pain levels, psychological variables (pain catastrophizing), and COMT rs4680 genotyping via venous blood samples. Telephone interviews at specified intervals enabled the application of binary logistic regressions and interaction models. ResultsSignificant influences of preoperative knee pain and pain catastrophizing on postsurgical outcomes were observed. Specifically, at the first time point (T1, 3 months post-TKA), a notable moderation effect was identified in preoperative knee pain (R2 change = 0.026, p = 0.026). The Johnson–Neyman regions of significance (RoS) indicated these moderation effects were significant above a threshold of 17.18 (p = 0.05), accounting for 26.4%. At the third time point (T3, 12 months post-TKA), a complex three-way interaction among genotypes (GG, GA, and AA carriers) was evident, resulting in an R2 change of 0.051 (p = 0.009). Here, the RoS for pain catastrophizing was above 32.74 for 30.5% of GG genotype carriers, above 22.38 for 50.8% of GA carriers, and below 11.94 for 63.2% of AA carriers. ConclusionThis study illuminates the significant role of the COMT Val158Met rs4680 polymorphism in susceptibility to prolonged pain following TKA. It also elucidates how these genetic genotypes interplay with preoperative knee pain and pain catastrophizing. Such intricate genetic-psychological-pain relationships necessitate additional investigation to confirm these findings and potentially guide post-TKA pain management strategies.

Efficacy of a Combined Periarticular and Intraosseous Multimodal Analgesic Injection Technique in Simultaneous Bilateral Total Knee Arthroplasty: A Randomized Controlled Trial.

Introduction Early postoperative pain poses a challenge for surgeons to manage after total knee arthroplasty (TKA). Various techniques have been employed to optimize pain reduction, including Periarticular Multimodal Analgesia (PMA), recognized as a safe and effective method. Our study aims to enhance PMA through a combined intraosseous injection (PMA-I) and compare it with standard PMA. Methods Forty patients undergoing simultaneous bilateral TKA surgery were enrolled. Patients were randomized to receive PMA-I on one side of the knee, while the contralateral knee received standard PMA. Pain scores, bleeding, and range of motion (ROM) were assessed in both groups. Results The PMA-I group demonstrated statistically significant lower visual analog scale (VAS) scores at all postoperative time points, except at 48 hours, where the difference was not statistically significant. Postoperative bleeding and ROM did not significantly differ between groups. Conclusion PMA-I demonstrated both statistically and clinically significant reduction in early post-TKA pain, without additional costs, providing a technique that can be used to optimize postoperative pain control in TKA.

Efficacy of Oral Nefopam on Multimodal Analgesia in Total Knee Arthroplasty: A Prospective, Double-Blind, Placebo-Controlled, Randomized Trial

BackgroundMultimodal analgesia is central to pain management after total knee arthroplasty (TKA). This study aimed to evaluate the efficacy of adding oral nefopam to multimodal analgesia for post-TKA pain management. MethodsIn this prospective, double-blind, placebo-controlled, randomized trial, 100 patients who underwent TKA at our hospital were randomized to either the nefopam or the control group. After surgery, patients in the nefopam group received 200 mg of celecoxib, 150 mg of pregabalin, and 40 mg of nefopam twice daily to control postoperative pain. Patients in the control group received 200 mg of celecoxib, 150 mg of pregabalin, and a placebo. Oxycodone hydrochloride (10 mg) was used as the rescue analgesic. If the pain remained poorly controlled, 10 mg of morphine hydrochloride was injected subcutaneously as a secondary rescue analgesic. The primary outcome was the postoperative consumption of oxycodone and morphine as rescue analgesics. Secondary outcomes were postoperative pain assessed using the visual analogue scale (VAS), functional recovery assessed by the range of knee motion and ambulation distance, time until hospital discharge, indicators of liver function, and complication rates. ResultsPatients in the nefopam group had significantly lower postoperative oxycodone and morphine consumption within 24 hours after surgery and during hospitalization, lower VAS pain scores at rest and during motion within 24 h after surgery, better functional recovery on postoperative days 1 and 2, and a shorter hospital stay. However, the absolute reduction in 0 to 24 h opioid consumption, VAS pain scores, and knee range of motion did not exceed the reported minimal clinically important difference. Both groups had similar indicators of liver function and complication rates. ConclusionsAdding oral nefopam to multimodal analgesia resulted in statistically significant improvements in opioid consumption, VAS pain scores, and functional recovery. However, the amount of improvement may not be clinically important.

Combined genicular artery embolization and genicular nerve block to treat chronic pain following total knee arthroplasty

BackgroundChronic knee pain after total knee arthroplasty (TKA) is a common complication that is difficult to treat. This report aims to highlight the benefit of combining embolotherapy and neurolysis intervention for symptomatic relief of post-TKA pain in a patient with long-standing pain refractory to conservative management.Case presentationA 77-year-old man who had previously undergone left knee arthroplasty has been grappling with worsening knee effusion and debilitating pain, resulting in limited mobility and progressive musculature deconditioning over a 20-year period. Diagnostic arteriography showed marked diffuse periarticular hyperemia around the medial and lateral joint spaces of the left knee, along with capsular distention. The patient initially underwent microsphere embolization to selectively target multiple branches of the genicular arteries, achieving a 50% reduction in pain at the one-month follow-up. Subsequently, the patient underwent image-guided genicular nerve neurolysis, targeting multiple branches of the genicular nerves, which led to further pain reduction (80% compared to the initial presentation or 60% compared to post-embolization) at the one-month follow-up. This improvement facilitated weight-bearing and enabled participation in physical therapy, with sustained pain relief over the 10-month follow-up period.ConclusionThe combination of genicular artery embolization and genicular nerve block may be a technically safe and effective option for alleviating chronic pain after total knee arthroplasty.

Predictors and Prevalence of Persistent Pain after Total Knee Arthroplasty in One-Year Follow-up.

Total knee arthroplasty (TKA) is one of the most common surgeries performed to reduce pain and disability in knee arthritis. Comprehension of the etiology and prevalence of persistent postoperative knee pain can help reduce this pain and identify the predictive factors leading to it. This study aimed to investigate the predictive factors and the prevalence of persistent pain after total knee arthroplasty in one-year follow-up. This was a prospective cohort study. Demographic data including age, sex, body mass index (BMI), hospital anxiety and depression scale (HADS), and comorbidities were collected. In 242 patients, preoperative and postoperative Western Ontario and McMaster Universities Arthritis Index (WOMAC) scores were measured before and immediately after surgery and in 3-, 6-, and 12-month intervals during follow-up. Loosening of the prosthesis was also investigated by radiographic imaging in every postoperative visit. WOMAC pain decreased from a mean (standard deviation) of 49 before surgery to 18 at 6 months and 13 at 12 months. Despite this, the prevalence of moderate-to-severe persistent postoperative pain (PPP) was 13.22% (n = 32) and 9.09% (n = 22) at 6 and 12 months lower preoperative WOMAC (odd's ratio:2.8), loosening of the prosthesis (odd's ratio:1.9), higher HADS (odd's ratio:2.1) were main predictors for PPP in TKA patients as in rheumatoid arthritis (odd's ratio:1.2). Loosening of the prosthesis and higher preoperative WOMAC scores are key factors in persistent post-TKA pain. Depression and anxiety are more popular among patients with more pain after TKA. RA is more prevalent in patients with PPP after TKA.

Oxidative stress mediates associations between preoperative psychosocial phenotype and pain-related outcomes at 6 months following total knee arthroplasty: a longitudinal cohort study.

Greater preoperative depression, anxiety, and pain catastrophizing are associated with more severe long-term pain following total knee arthroplasty (TKA). In a secondary analysis of previously reported data, we tested the hypothesis that these associations are mediated by oxidative stress (OS). A mixed between/within-subjects longitudinal cohort design. A single academic medical center. Osteoarthritis patients (n = 91; 62.6% female) undergoing unilateral TKA. We assessed depression, anxiety, and catastrophizing, as well as markers of central sensitization (widespread pain, temporal summation of pain) preoperatively. Blood samples were then obtained immediately prior to intraoperative tourniquet placement for quantification of in vivo biomarkers of systemic OS, F2-isoprostanes and isofurans. Post-TKA pain intensity (numeric rating scale worst pain [NRS], McGill Pain Questionnaire-2 [MPQ-2]) and function (PROMIS Pain Interference) were assessed at 6 months following TKA. Greater preoperative depression, catastrophizing, and widespread pain were associated with higher intraoperative combined OS (F2-isoprostanes+isofurans/2), which was in turn associated with higher post-TKA pain intensity and worse function (P < .05). All preoperative phenotype predictors except anxiety were correlated positively with post-TKA pain and/or function (P < .05). Bootstrapped mediation analyses revealed significant (P < .05) indirect (mediated) effects of depression (NRS Worst Pain, MPQ-2, PROMIS Pain Interference), anxiety (MPQ-2, PROMIS Pain Interference), and catastrophizing (PROMIS Pain Interference) on adverse long-term post-TKA outcomes via elevated OS. Central sensitization-related predictors demonstrated only direct effects (P < .05) on post-TKA outcomes that were independent of OS mechanisms. Results suggest that the adverse impact of depression, anxiety, and pain catastrophizing on post-TKA pain and functional outcomes are mediated in part by elevated OS.

Acute postoperative pain and dorsal root ganglia transcriptomic signatures following total knee arthroplasty (TKA) in rats: An experimental study.

Total knee arthroplasty (TKA) is the final treatment option for patients with advanced knee osteoarthritis (OA). Unfortunately, TKA surgery is accompanied by acute postoperative pain that is more severe than arthroplasty performed in other joints. Elucidating the molecular mechanisms specific to post-TKA pain necessitates an animal model that replicates clinical TKA procedures, induces acute postoperative pain, and leads to complete functional recovery. Here, we present a new preclinical TKA model in rats and report on functional and behavioral outcomes indicative of pain, analgesic efficacy, serum cytokine levels, and dorsal root ganglia (DRG) transcriptomes during the acute postoperative period. Following TKA, rats exhibited marked deficits in weight bearing that persisted for 28 days. Home cage locomotion, rearing, and gait were similarly impacted and recovered by day 14. Cytokine levels were elevated on postoperative days one and/or two. Treatment with morphine, ketorolac, or their combination improved weight bearing while gabapentin lacked efficacy. When TKA was performed in rats with OA, similar functional deficits and comparable recovery time courses were observed. Analysis of DRG transcriptomes revealed upregulation of transcripts linked to multiple molecular pathways including inflammation, MAPK signaling, and cytokine signaling and production. In summary, we developed a clinically relevant rat TKA model characterized by resolution of pain and functional recovery within five weeks and with pain-associated behavioral deficits that are partially alleviated by clinically administered analgesics, mirroring the postoperative experience of TKA patients.

A Randomized Controlled Pilot Study Using Ultrasound-Guided Percutaneous Cryoneurolysis of the Infrapatellar Branch of the Saphenous Nerve for Analgesia Following Total Knee Arthroplasty.

Total knee arthroplasty (TKA) is frequently associated with severe, prolonged postsurgical pain, and therefore local anesthetic-based peripheral nerve blocks are commonly used for postoperative analgesia. Cryoneurolysis involves the use of freezing temperatures to provide a reversible sensory (and motor) block with a duration measured in weeks and months, more commensurate with the typical period of post-TKA pain. We therefore conducted a randomized controlled pilot study to evaluate the use of this modality for the treatment of pain following TKA to (1) determine the feasibility of and optimize the study protocol for a subsequent definitive clinical trial; and (2) estimate analgesia and opioid reduction within the first 3 postoperative weeks. A convenience sample of 16 patients undergoing primary TKA with a single-injection and/or continuous adductor canal nerve block were randomized to receive either active cryoneurolysis or a sham procedure targeting the infrapatellar branch of the saphenous nerve, in a participant-masked fashion. This was a pilot study with a relatively small number of participants, and therefore resulting data were not analyzed statistically. Compared with participants receiving sham, the active treatment group reported slightly lower average and worst pain scores as well as opioid consumption and sleep disturbances due to pain at a majority of postoperative time points between postoperative days (POD) 4-21. Preoperative ultrasound-guided cryoneurolysis of the infrapatellar branch of the saphenous nerve is feasible and may provide analgesic benefits for multiple weeks following TKA. A definitive randomized controlled trial appears warranted.

ID:16184 Dorsal Root Ganglion Stimulation for Chronic Pain Following Total Knee Arthroplasty: A Review

A modest subset of patients who undergo total knee arthroplasty (TKA) will subsequently develop chronic neuropathic knee pain. Initially, patients are treated conservatively with tricyclic antidepressants, serotonin-norepinephrine reuptake inhibitors, gabapentinoids, and peripheral nerve blocks with subsequent radiofrequency ablation. With advancements in neuromodulation, particularly dorsal root ganglion stimulation (DRG-S), promising outcomes with sustained pain relief have been shown. Our aim is to review the current literature on the management of chronic neuropathic post-TKA pain with DRG-S.

Perioperative oxidative stress predicts subsequent pain-related outcomes in the 6 months after total knee arthroplasty.

Total knee arthroplasty (TKA) is effective for pain reduction in most patients, but 15% or more report unsatisfactory long-term pain outcomes. We tested whether oxidative stress (OS) related to extended tourniquet application during TKA and subsequent ischemic reperfusion (IR) contributed to adverse post-TKA pain outcomes. Blood samples were obtained in 91 patients with osteoarthritis (63% female) undergoing TKA before tourniquet placement (T1), 45 minutes after tourniquet inflation (T2), and 15 minutes after tourniquet removal (T3). Plasma levels of F 2 -isoprostanes and isofurans, the most specific measures of in vivo OS, were quantified. Pain intensity and function were assessed at baseline and again at 6 weeks and 6 months after TKA. Results indicated that higher Combined OS (F 2 -isoprostanes + isofurans/2) at T1 baseline and larger increases in Combined OS from T1 to T2 were associated with higher baseline-corrected past 24-hour worst and average pain intensity (numeric rating scale) and higher past week McGill Pain Questionnaire-2 total scores at 6-month follow-up ( P 's < 0.05). Increases in Combined OS from T1 to T3, which should most directly capture OS and IR injury related to tourniquet use, were not associated with short-term or long-term post-TKA pain outcomes. Longer ischemia duration was unexpectedly associated with lower baseline-corrected pain intensity at 6-month follow-up. Combined OS was not linked to functional outcomes at either follow-up. Elevated perioperative OS seems to exert small but significant adverse effects on long-term post-TKA pain outcomes, although this OS seems unrelated to IR injury associated with extended tourniquet use.

Identification of biological risk factors for persistent postoperative pain after total knee arthroplasty

BackgroundThere is growing evidence that cytokines and adipokines are associated with osteoarthritis (OA) severity, progression, and severity of associated pain. However, the cytokine response to total knee arthroplasty (TKA) and...

Efficacy and safety of duloxetine for postoperative pain after total knee arthroplasty in centrally sensitized patients: study protocol for a randomized controlled trial

BackgroundPostoperative residual knee pain after total knee arthroplasty (TKA) is a significant factor that contributes to patient dissatisfaction. Patients with preoperative central sensitization (CS) may be more susceptible to unexplained chronic pain after TKA, and duloxetine has been reported to be effective in post-TKA pain control in patients with CS. However, there remains limited evidence to support this off-label use in routine clinical practice. Hence, we designed this randomized, placebo-controlled, triple-blind clinical trial to evaluate the effects of preoperative screening and targeted duloxetine treatment of CS on postoperative residual pain compared with the care-as-usual control group.MethodsThis randomized controlled trial includes patients with knee osteoarthritis on a waiting list for primary unilateral TKA. Patients with preoperative CS will be randomly allocated to the perioperative duloxetine treatment group (duloxetine group) or the care-as-usual control group (placebo group). Patients in the duloxetine group will receive a half-dose of preemptive duloxetine (30 mg/day) for a week before surgery and a full-dose of duloxetine (60 mg/day) for six weeks after surgery. The primary outcome is the intensity of residual pain at six months after TKA, including the visual analogue scale, 11-point numeric rating scale, the sensory dimension of the brief pain inventory, and the pain subscale of the Knee injury and Osteoarthritis Outcome Score. The secondary outcome measures will include the pain and function related outcomes. All of the patients will be followed up at one, three, and six months after surgery. All adverse events will be recorded and immediately reported to the primary investigator and ethics committee to decide if the patient needs to drop out from the trial.DiscussionThis clinical trial will convey the latest evidence of the efficacy and safety of the application of duloxetine in postoperative pain control in CS patients who are scheduled for TKA. The study results will be disseminated at national and international conferences and published in peer-reviewed journals.Trial registrationChinese Clinical Trial Registry (http://www.chictr.org.cn) registration number: ChiCTR2000031674. Registered 07 April 2020.

Use of spinal cord stimulation for the treatment of post total knee arthroplasty pain.

Total knee arthroplasty (TKA), a common elective surgical procedure, is indicated in patients with knee pain that becomes refractory to nonsurgical interventions, such as weight loss, physical activity, physical therapy, and pharmacologic treatment. However, postoperative chronic pain is frequently reported and may lead to opioid use and dependence. Due to the increasing concern of the overuse of opioids in medical treatments, a search for other viable options is recognized. As a consequence, alternative therapies, such as transcutaneous electrical nerve stimulation (TENS), pulsed radiofrequency (PRF), and spinal cord stimulation (SCS) are being tried to potentially replace traditional opioid use in treating persistent postsurgical pain (PPSP), thus reducing opioid dependence across the nation. Here, we provide a brief overview of persistent pain following TKA procedures, with a particular emphasis on the role of promising therapies, such as TENS, PRF, and SCS for the treatment of post-TKA pain.

AAAPT Diagnostic Criteria for Acute Knee Arthroplasty Pain.

The relationship between preexisting osteoarthritic pain and subsequent post-total knee arthroplasty (TKA) pain is not well defined. This knowledge gap makes diagnosis of post-TKA pain and development of management plans difficult and may impair future investigations on personalized care. Therefore, a set of diagnostic criteria for identification of acute post-TKA pain would inform standardized management and facilitate future research. The Analgesic, Anesthetic, and Addiction Clinical Trial Translations, Innovations, Opportunities, and Networks (ACTTION) public-private partnership with the US Food and Drug Administration (FDA), the American Pain Society (APS), and the American Academy of Pain Medicine (AAPM) formed the ACTTION-APS-AAPM Pain Taxonomy (AAAPT) initiative to address this goal. A multidisciplinary work group of pain experts was invited to conceive diagnostic criteria and dimensions of acute post-TKA pain. The working group used contemporary literature combined with expert opinion to generate a five-dimensional taxonomical structure based upon the AAAPT framework (i.e., core diagnostic criteria, common features, modulating factors, impact/functional consequences, and putative mechanisms) that characterizes acute post-TKA pain. The diagnostic criteria created are proposed to define the nature of acute pain observed in patients following TKA.

Comparison of the Post-Total Knee Arthroplasty Analgesic Effect of Intraoperative Periarticular Injection of Different Analgesics

To compare post-TKA (total knee arthroplasty) analgesic effect of periarticular injection of different analgesics during surgery. Experimental study. Tianjin People's Hospital, from December 2016 to July 2018. Patients undergoing unilateral TKA were randomly divided into Group A and Group B, with 67 patients in each group. In Group A, compound analgesics of ropivacaine, ketorolac, adrenaline, morphine and normal saline were injected periarticularly during surgery. While in Group B, compound analgesics of bupivacaine, methylprednisolone, adrenalin, morphine and normal saline were injected periarticularly during surgery. Visual analogue scale (VAS), range of motion (ROM) of knee joint, and rehabilitation of knee joint of both groups were compared. VAS scores of Group A at 6-hour, 24-hour, 48-hour and 72-hour after surgery was lower than those of Group B (p=0.046, p<0.001, p<0.001 and p<0.001, respectively). ROM of knee joint of Group A on the 3rd, 7th, 10th and 14th day after surgery was superior to that of Group B (all p<0.001). On the 14th day after surgery, excellent and good rate of rehabilitation of knee joint of Group A was higher than that of Group B (p=0.032). Compared with periarticular injection of compound analgesics of bupivacaine, methylprednisolone, adrenaline, morphine and normal saline during surgery, periarticular injection of compound analgesics of ropivacaine, ketorolac, adrenaline, morphine and normal saline during surgery can alleviate post-TKA pain more effectively, improve early ROM of joint knee after surgery, increase rehabilitation effect of knee joint.