title: Prospective relation between catastrophizing and residual pain following knee arthroplasty: two-year follow-up. Predicting the outcome of total knee arthroplasty. Clinical importance of changes in chronic pain intensity measured on an 11-point numerical pain rating scale Predicting Total Knee Replacement Pain: A Prospective, Observational Study Behavioral dimensions of adjustment in persons with chronic pain: pain-related anxiety and acceptance The Roles of Pain Catastrophizing and Anxiety in the Prediction of Postoperative Pain Intensity: A Prospective Study Reduction of pain catastrophizing mediates the outcome of both physical and cognitive-behavioral treatment in chronic low back pain. Validation study of WOMAC: a health status instrument for measuring clinically important patient relevant outcomes to antirheumatic drug therapy in patients with osteoarthritis of the hip or knee. Defining the clinically important difference in pain outcome measures Catastrophizing and depressive symptoms as prospective predictors of outcomes following total knee replacement. Predicting pain after total knee arthroplasty. Are psychological predictors of chronic postsurgical pain dependent on the surgical model? A comparison of total knee arthroplasty and breast surgery for cancer. Gabapentin reduces preoperative anxiety and pain catastrophizing in highly anxious patients prior to major surgery: a blinded randomized placebo-controlled trial Preoperative predictors of pain following total knee arthroplasty. Psychological determinants of problematic outcomes following Total Knee Arthroplasty The role of presurgical expectancies in predicting pain and function one year following total knee arthroplasty
abstract: BACKGROUND Pain is the primary indication for both primary and revision total knee arthroplasty ( TKA ) ; however , most arthroplasty outcome measures do not take pain into account . OBJECTIVE To document the prospect i ve pain experience following TKA , with subjective pain-specific question naires to determine if comorbidities , preoperative pain or preoperative pain catastrophizing scores are predictive of long-term pain outcomes . METHODS Fifty-five patients with a primary diagnosis of osteoarthritis of the knee , who were scheduled to undergo TKA , were asked to fill out the McGill Pain Question naire ( MPQ ) and the Pain Catastrophizing Scale ( PCS ) preoperatively and at three , 12 and 24 months follow-up . Comorbidities were extracted from the Queen Elizabeth II Health Sciences Centre health information system . RESULTS The overall response rate ( return of completed question naires ) was 84 % . There was a significant decrease in the MPQ scores ( P<0.05 ) postoperatively . PCS scores did not change over time . Receiver operating characteristic curves revealed the number of comorbidities per patient predicted the presence of pain postoperatively , as documented by the numerical rating subscale of the MPQ at 24 months ( P<0.05 ) . Receiver operating characteristic curves for preoperative PCS and rumination subscale scores predicted the presence of pain , as measured by the Pain Rating Index subscale of the MPQ at 24 months ( P<0.05 ) . Preoperative PCS scores and comorbidities were significantly higher in the persistent pain group ( P<0.05 ) . CONCLUSIONS The number of comorbidities predicted the presence of pain at 24 months follow-up and , for the first time , preoperative PCS scores were shown to predict chronic postoperative pain . This may enable the identification of knee arthroplasty patients at risk for persistent postoperative pain , thus allowing for efficient administration of preoperative interventions to improve arthroplasty outcomes BACKGROUND The relief of pain and the restoration of functional activities are the main outcomes of primary total knee arthroplasty for the treatment of osteoarthritis . This paper examines the preoperative predictors of pain and functional outcome at one and two years following total knee arthroplasty . METHODS Patients were recruited for a prospect i ve observational study of primary total knee arthroplasty for the treatment of osteoarthritis from centers in the United States , the United Kingdom , and Australia . Research assistants recruited the patients and collected the clinical history and physical examination data preoperatively and at three , twelve , and twenty-four months postoperatively . The Western Ontario and McMaster University Osteoarthritis Index ( WOMAC ) , Short Form-36 ( SF-36 ) , and demographic data were obtained by self-administered patient question naires . RESULTS We recruited 860 patients and obtained one-year WOMAC data on 759 patients ( 88 % ) and two-year data on 701 ( 82 % ) . The mean age was seventy years , and 59 % of the patients were female . Using hierarchical regression models , we found that the most significant preoperative predictors of worse scores on the pain and function domains of the WOMAC scale and on the physical functioning domain of the SF-36 at one and two years postoperatively were low preoperative scores , a higher number of comorbid conditions , and a low SF-36 mental health score . After adjusting for these predictors , we found that the functional status of the patients from the United Kingdom was significantly worse than that of the patients from the other countries and the difference was clinical ly important at both the one-year and two-year follow-up examination ( p < 0.0005 ) . The mean WOMAC pain scores for the three countries were not significantly different at one year , and , although they were significantly different at two years ( p = 0.025 ) , the difference was not clinical ly important . CONCLUSIONS Patients who have marked functional limitation , severe pain , low mental health score , and other comorbid conditions before total knee arthroplasty are more likely to have a worse outcome at one year and two years postoperatively . After adjusting for these predictors , it was found that patients from the United Kingdom had significantly worse functional outcomes but similar pain relief compared with those from the United States and Australia & NA ;  Pain intensity is frequently measured on an 11‐point pain intensity numerical rating scale ( PI‐NRS ) , where 0=no pain and 10=worst possible pain . However , it is difficult to interpret the clinical importance of changes from baseline on this scale ( such as a 1‐ or 2‐point change ) . To date , there are no data driven estimates for clinical ly important differences in pain intensity scales used for chronic pain studies . We have estimated a clinical ly important difference on this scale by relating it to global assessment s of change in multiple studies of chronic pain . Data on 2724 subjects from 10 recently completed placebo‐controlled clinical trials of pregabalin in diabetic neuropathy , postherpetic neuralgia , chronic low back pain , fibromyalgia , and osteoarthritis were used . The studies had similar design s and measurement instruments , including the PI‐NRS , collected in a daily diary , and the st and ard seven‐point patient global impression of change ( PGIC ) , collected at the endpoint . The changes in the PI‐NRS from baseline to the endpoint were compared to the PGIC for each subject . Categories of ‘ much improved ’ and ‘ very much improved ’ were used as determinants of a clinical ly important difference and the relationship to the PI‐NRS was explored using graphs , box plots , and sensitivity/specificity analyses . A consistent relationship between the change in PI‐NRS and the PGIC was demonstrated regardless of study , disease type , age , sex , study result , or treatment group . On average , a reduction of approximately two points or a reduction of approximately 30 % in the PI‐NRS represented a clinical ly important difference . The relationship between percent change and the PGIC was also consistent regardless of baseline pain , while higher baseline scores required larger raw changes to represent a clinical ly important difference . The application of these results to future studies may provide a st and ard definition of clinical ly important improvement in clinical trials of chronic pain therapies . Use of a st and ard outcome across chronic pain studies would greatly enhance the comparability , validity , and clinical applicability of these studies To describe the natural history of pain after total knee arthroplasty and to identify factors predicting excessive postoperative pain , we used a prospect i ve , observational study assessing clinical and radiographic variables preoperatively and at 1 , 3 , 6 , and 12 months after knee replacement .  Data sources included the visual analog pain scale and other measures of patient health , psychologic state , and component reliability . Regression analyses were conducted to identify specific factors predictive of postoperative pain , controlling for ine quality of variables , and confirmed using regression diagnostics . For 116 patients ( 149 knees ; mean age , 66 years ; 55.2 % women ) , significant pain was reported by 72.3 % , 44.4 % , 22.6 % , 18.4 % , and 13.1 % , respectively . No intergroup differences existed for anesthesia , weight , age , or gender . Patients with greater preoperative pain had more postoperative pain , used more home therapy , and postoperative manipulations . Preoperative depression and anxiety were associated with heightened pain at 1 year . Pain after knee replacement resolves quickly , declining to approximately 1/2 by 3 months . However , one in eight patients report moderate to severe pain 1 year after surgery despite an absence of clinical or radiographic abnormalities . Development of office-based preoperative screening tools and interventions for these patients may reduce postoperative costs and improve patient-perceived outcomes Through empirical methods we now characterize patients with chronic pain as either dysfunctional , interpersonally distressed , or adaptive copers . Study ing factors that differentiate these groups may reveal the behavioral processes that determine adjustment to pain . Subjects for this study were 190 patients referred for treatment of chronic pain . They were classified as dysfunctional ( n = 41 ) , interpersonally distressed ( n = 28 ) or adaptive copers ( n = 59 ) based on the Multidimensional Pain Inventory ( Kerns , R.D. , Turk , D.C. and Rudy , T.E. , The West Haven-Yale Multidimensional Pain Inventory ( WHYMPI ) , Pain , 23 ( 1985 ) 345 - 356 ) and compared on measures of  pain-related anxiety and pain acceptance .  Our analyses showed that the dysfunctional group reported greater pain-related anxiety and less acceptance of pain than the other groups . Additional analyses , statistically controlling for pain severity and depression , showed that the patient subtypes continued to differ on pain-related anxiety and acceptance . Discriminant function analyses including pain-related anxiety and acceptance correctly classified 72.5 % of dysfunctional and 90.9 % of adaptive copers . Again , anxiety and acceptance contributed uniquely to classification independent of depression and pain intensity . Pain-related anxiety and acceptance of pain appear to be unique behavioral dimensions of adjustment to chronic pain . Decreasing anxiety and increasing acceptance may ' move ' patients with chronic pain from the dysfunctional to the adaptive coper category Objectives : This study was a prospect i ve investigation of the extent to which psychologic variables could be predictive of postoperative pain . Study aims were : 1 ) to evaluate whether an assessment of pre-operative distress factors could predict the intensity of postoperative pain ; and 2 ) to characterize the unique pattern in which anxiety and pain catastrophizing scores relate to postoperative pain . Methods : The Pain Catastrophizing Scale and the State-Trait Anxiety Inventory were administered to 38 patients scheduled for elective abdominal surgery .  The question naires were completed on the day of admission , a day before the operation . On day 1 and day 2 following the operation , perception of pain intensity at the surgical wound was assessed by visual analog scale . Results : The Pain Catastrophizing Scale and State-Trait Anxiety Inventory scores were significantly correlated with the postoperative pain scores . A linear regression analysis showed that Pain Catastrophizing Scale predicted the level of postoperative pain intensity even after controlling for state anxiety and that trait anxiety was not a significant predictor . In addition , analysis of the unique pattern of each predictor related to postoperative pain intensity indicated a linear curve for the Pain Catastrophizing Scale and curvilinear curve for the state anxiety . Discussion : The results are discussed in light of appraisal and coping theories . It is suggested that a simple assessment of preoperative catastrophizing tendency and anxiety scores may assist medical teams in postoperative pain management UNLABELLED The aim of this study was to examine whether treatments based on different theories change pain catastrophizing and internal control of pain , and whether changes in these factors mediate treatment outcome . Participants were 211 patients with nonspecific chronic low back pain ( CLBP ) participating in a r and omized controlled trial , attending active physical treatment ( APT , n = 52 )  , cognitive-behavioral treatment ( CBT , n = 55 ) , treatment combining the APT and CBT ( CT , n = 55 ) , or waiting list ( WL , n = 49 ) . Pain catastrophizing decreased in all 3 active treatment groups and not in the WL . There was no difference in the change in internal control across all 4 groups . In all the active treatment groups , patients improved regarding perceived disability , main complaints , and current pain at post-treatment , and no changes were observed in the WL group . Depression only changed significantly in the APT group . Change in pain catastrophizing mediated the reduction of disability , main complaints , and pain intensity . In the APT condition , pain catastrophizing also mediated the reduction of depression . Not only cognitive-behavioral treatments but also a physical treatment produced changes in pain catastrophizing that seemed to mediate the outcome of the treatment significantly . The implication s and limitations of these results are discussed . PERSPECTIVE This article shows that treatment elements that do not deliberately target cognitive factors can reduce pain catastrophizing . Reduction in pain catastrophizing seemed to mediate the improvement of functioning in patients with chronic low back pain . The results might contribute to the development of more effective interventions Within the context of a double blind r and omized controlled parallel trial of 2 nonsteroidal antiinflammatory drugs , we vali date d WOMAC , a new multidimensional , self-administered health status instrument for patients with osteoarthritis of the hip or knee . The pain , stiffness and physical function subscales fulfil conventional criteria for face , content and construct validity , reliability , responsiveness and relative efficiency . WOMAC is a disease-specific purpose built high performance instrument for evaluative research in osteoarthritis clinical trials & NA ; The purpose of this study was to determine the levels of change on st and ard pain scales that represent clinical ly important differences to patients . Data from analgesic studies are often difficult to interpret because the clinical importance of the results is not obvious . Differences between groups , as summarized by a change in mean values over time , can be difficult to apply to clinical care . Baseline scores vary widely and group mean differences could reflect large changes in a few patients , small changes in many patients , or any combination of these outcomes . Determination of the proportion of patients who have a clinical ly important improvement in their pain would provide a more interpretable result with direct clinical implication s. However , determining a clinical ly important outcome requires information about the degree of change over time that is clinical ly important . Data from the titration phase of a multiple cross‐over r and omized clinical trial of oral transmucosal fentanyl citrate ( OTFC )  for the treatment of cancer‐related breakthrough pain were re‐analyzed to examine the differences in pain scores between treatment episodes that did and did not yield adequate pain relief . The scales evaluated were absolute pain intensity difference ( PID , 0–10 scale ) , percentage pain intensity difference ( PID% , 0–100 % scale ) , pain relief ( PR , 0 ( none ) , 1 ( slight ) , 2 ( moderate ) , 3 ( lots ) , 4 ( complete ) ) , sum of the pain intensity difference ( SPID over 60 min ) , percentage of maximum total pain relief ( % Max TOTPAR over 60 min ) , and global medication performance ( 0 ( poor ) , 1 ( fair ) , 2 ( good ) , 3 ( very good ) , 4 ( excellent ) ) . Adequate relief was defined by the patient 's decision not to use another dose of opioid medication as a rescue , in addition to the study medication , to treat each painful episode . One hundred thirty OTFC naive patients contributed data on 1268 episodes of breakthrough pain . The scales that were converted to a percentage change yielded the best accuracy in predicting adequate relief , with balanced sensitivity and specificity . The best cut‐off point for both the % Max TOTPAR and the PID% was 33 % . The best cut‐off points for the absolute scales were absolute pain intensity difference of 2 , pain relief of 2 ( moderate ) , and SPID of 2 . The global medication performance of 2 ( good ) had excellent values as well . This study presents data ‐derived cut‐off points for the changes in several pain scales , each reflecting the clinical ly important improvement for patients treating breakthrough cancer pain episodes with OTFC . Confirmation in other patient population s and different pain syndromes will be needed . The use of consistent clinical ly important cut‐off points as the primary outcome in future pain therapy clinical trials will enhance their validity , comparability , and clinical applicability Several recent reports suggest that pain-related catastrophizing  is a risk factor for poor acute pain outcomes following surgical interventions . However , it has been less clear whether levels of catastrophizing influence longer-term postoperative outcomes . Data were analyzed from a relatively small number ( n=43 ) of patients who underwent total knee replacement and were followed for 12 months after their surgery . Previous research has suggested that high levels of both catastrophizing and depression are associated with elevated acute postoperative pain complaints among patients undergoing knee surgery . In this sample ,  catastrophizing and depression at each of the assessment points were studied as prospect i ve predictors of pain ( both global pain ratings and pain at night ) at the subsequent assessment point over the course of one year . The predictive patterns differed somewhat across measures of pain reporting ; depressive symptoms were unique predictors of greater global pain complaints , while catastrophizing was a specific and unique predictor of elevated nighttime pain . While surgical outcomes following total knee replacement are , on average , quite good , a significant minority of patients continue to experience long-term pain . The present findings suggest that high levels of catastrophizing and depression may promote enhanced pain levels , indicating that interventions design ed to reduce catastrophizing and depressive symptoms may have the potential to further improve joint replacement outcomes Six hundred twenty-two primary total knee arthroplasties were studied prospect ively in 512 patients . A group with no pain and one with severe pain at 5 years were statistically compared . The following were significant predictors of poor pain outcomes :  age below 60 ( 17 % ) compared with above 60 ( 7 % , P < .05 ) . The first knee was most likely to be in the poor outcome group ( 13 % ) compared with the second knee ( 6 % ) . In contrast , patients who underwent simultaneous bilateral arthroplasty faired better ( 2 % , P < .01 ) . Performing lateral release and sacrificing the posterior cruciate ligament also significantly predicted for poor pain outcomes but may have been influenced by selection bias . We conclude that avoiding surgery in patients younger than 60 and choosing a simultaneous approach to bilateral disease reduce the chance of poor pain outcomes UNLABELLED Anxiety , depression , and catastrophizing are generally considered to be predictive of chronic postoperative pain , but this may not be the case after all types of surgery , raising the possibility that the results depend on the surgical model . We assessed the predictive value of these factors for chronic postsurgical pain in 2 different surgical models : total knee arthroplasty for osteoarthritis ( 89 patients , 65 % women , age = 69 ± 9 years , baseline pain intensity = 4.7 ± 2.1 ) and breast surgery for cancer ( 100 patients , 100 % women , age = 55 ± 12 years , no preoperative pain ) . Data were collected before surgery , then 2 days and 3 months after surgery . Anxiety , depression , and catastrophizing were measured with the Spielberger State-Trait Anxiety Inventory , Beck Depression Inventory , and Pain Catastrophizing Scale , respectively . Pain was assessed with the  Brief Pain Inventory  . Neuropathic pain was detected with the DN4 question naire . Multivariate logistic regression analyses for the total knee arthroplasty and breast surgery models considered together indicated that the presence of clinical ly meaningful chronic pain at 3 months ( pain intensity ≥3/10 ) was predicted independently by age ( P = .04 ) , pain intensity on day 2 ( P = .009 ) , and state anxiety ( P = .001 ) . Linear regression models also showed that pain magnification , one of the dimensions of catastrophizing , independently predicted chronic pain intensity ( P = .04 ) . These results were not affected by the surgical model or by the neuropathic characteristics of the pain . Thus , state anxiety and pain magnification seem to constitute psychological risk factors for chronic postsurgical pain relevant in all surgical models . PERSPECTIVE This prospect i ve study performed in patients with total knee arthroplasty or breast surgery for cancer shows that state anxiety , amplification of pain , and acute postoperative pain independently predict postsurgical pain at 3 months and that this does not depend on the surgical model Introduction Gabapentin is increasingly being used for the treatment of postoperative pain and a variety of psychiatric diseases , including chronic anxiety disorders . Trials have reported mixed results when gabapentin has been administered for the treatment of preoperative anxiety . We tested the hypothesis that gabapentin 1,200 mg vs placebo would reduce preoperative anxiety in patients who exhibit moderate to high preoperative anxiety . Methods A blinded r and omized controlled trial was conducted from September 2009 to June 2011 at the Toronto General Hospital . Following ethics approval and informed consent , 50 female patients with a 0 - 10 numeric rating scale ( NRS ) anxiety score of greater than or equal to 5/10 consented to receive either gabapentin 1,200  mg ( n = 25 ) or placebo ( n = 25 ) prior to surgery . R and omization was computer generated , and the Investigational Pharmacy was responsible for the blinding and dispensing of medication . All patients and care providers , including physicians , nurses , and study personnel , were blinded to group allocation . Before administering the study medication , baseline anxiety levels were measured using a NRS , the Spielberger State-Trait Anxiety Inventories , the Pain Catastrophizing Scale , and the Pain Anxiety Symptoms Scale-20 . Baseline pain intensity ( 0 - 10 NRS ) and level of sedation ( 0 - 10 NRS and Richmond Agitation-Sedation Scale [ RASS ] ) were also measured . Two hours after the administration of gabapentin or placebo ( prior to surgery ) , patients again rated their anxiety , pain , and sedation levels using the same measurement tools as at baseline . The main outcome was a reduction in preoperative anxiety . Results Forty-four patients ( 22 treated with gabapentin 1,200 mg and 22 treated with placebo ) were included in the analysis of the primary outcome . Analysis of covariance in which pre-drug NRS anxiety scores were used as the covariate showed that post-drug preoperative NRS anxiety ( Effect size , 1.44 ; confidence interval [ CI ] 0.19 to 2.70 ) and pain catastrophizing ( Effect size , 0.43 ; CI 0.12 to 0.74 ) scores were significantly lower in the gabapentin group than in the placebo control group , respectively . Post-drug sedation ( Effect size , −3.02 ; CI −4.28 to −1.77 ) and RASS ( Effect size , 0.41 ; CI 0.12 to 0.71 ) scores were significantly higher in the gabapentin group than in the placebo group , respectively . Conclusions Administration of gabapentin 1,200 mg prior to surgery reduces preoperative NRS anxiety scores and pain catastrophizing scores and increases sedation prior to entering the operating room . These results suggest that gabapentin 1,200 mg may be a treatment option for patients who exhibit high levels of preoperative anxiety and pain catastrophizing ;  however , the sedative properties of the medication and the possibility of delayed postoperative discharge in the elective ambulatory population need to be considered . Résumé Introduction La gabapentine est de plus en plus utilisée pour le traitement de la douleur postopératoire ainsi que pour le traitement de plusieurs maladies psychiatriques , notamment les troubles anxieux chroniques . Des études ont rapporté des résultats mitigés lors de l’administration de gabapentine pour le traitement de l’anxiété préopératoire . Nous avons testé l’hypothèse que 1200 mg de gabapentine vs. un placebo réduirait l’anxiété préopératoire chez les patients manifestant une anxiété préopératoire modérée à élevée . MéthodeNous avons réalisé une étude r and omisée contrôlée en aveugle entre septembre 2009 et juin 2011 à l’Hôpital général de Toronto . Après avoir obtenu l’approbation du comité d’éthique et le consentement éclairé des sujets de l’étude , 50 patientes ayant un score d’anxiété sur une échelle d’évaluation numérique ( ÉÉN ) de 0 - 10 supérieur ou égal à 5/10 ont consenti à recevoir 1200 mg de gabapentine ( n = 25 ) ou un placebo ( n = 25 ) avant la chirurgie . La r and omisation a été effectuée par ordinateur , et le département de pharmacie était en charge de la mise en aveugle et de l’administration du médicament . Personne parmi les patientes ou les fournisseurs de soins , y compris les médecins , les infirmières et le personnel de recherche , ne connaissait l’attribution des groupes . Avant l’administration du médicament à l’étude , les niveaux d’anxiété de base ont été mesurés à l’aide d’une ÉÉN , des inventaires d’anxiété situationnelle et de trait d’anxiété de Spielberger , de l’échelle de catastrophisation de la douleur , et de l’échelle des symptômes d’anxiété face à la douleur 20 . L’intensité de la douleur de base ( ÉÉN 0 - 10 ) et le niveau de sédation ( ÉÉN 0 - 10 et échelle de sédation-agitation de Richmond [ RASS ] ) ont également été mesurés . Deux heures après l’administration de la gabapentine ou du placebo ( avant la chirurgie ) , les patientes ont à nouveau attribué une note à leur anxiété , à leur douleur , et aux niveaux de sédation à l’aide des mêmes outils de mesure qu’au début . Le critère d’évaluation principal était une réduction de l’anxiété préopératoire . RésultatsQuarante-quatre patientes ( 22 traitées avec 1200 mg de gabapentine et 22 traitées avec placebo )  ont été incluses dans l’analyse du critère d’évaluation principal . L’analyse de la covariance , utilisant les scores d’anxiété sur l’ÉÉN avant l’administration du médicament comme covariable , a démontré que les scores d’anxiété préopératoire sur l’ÉÉN après l’administration du médicament ( ampleur de l’effet , 1,44 ; intervalle de confiance [ IC ] 0,19 à 2,70 ) et de catastrophisation de la douleur ( ampleur de l’effet , 0,43 ; IC 0,12 à 0,74 ) étaient significativement plus bas dans le groupe gabapentine que dans le groupe témoin placebo , respectivement . Les scores de sédation après administration du médicament ( ampleur de l’effet , −3.02 ; IC −4,28 à −1,77 ) et de RASS ( ampleur de l’effet , 0,41 ; IC 0,12 à 0,71 ) étaient significativement plus élevés dans le groupe gabapentine que dans le groupe placebo , respectivement . Conclusion L’administration de 1200 mg de gabapentine avant la chirurgie réduit les scores d’anxiété préopératoire sur l’ÉÉN ainsi que les scores de catastrophisation de la douleur , et augmente la sédation avant l’entrée en salle d’opération . Ces résultats suggèrent que 1200 mg de gabapentine pourraient constituer une option de traitement pour les patients manifestant des niveaux élevés d’anxiété préopératoire et de catastrophisation de la douleur ; toutefois , les propriétés sédatives du médicament et la possibilité d’un délai dans le congé postopératoire dans la population ambulatoire pour chirurgies non urgentes doivent être prises en compte Total knee arthroplasty has provided dramatic improvements in function and pain for the majority of patients with knee arthritis , yet a significant proportion of patients remain dissatisfied with their results . We performed a prospect i ve analysis of 215 patients undergoing TKA who underwent a comprehensive array of evaluations to discover whether any preoperative assessment could predict high pain scores and functional limitations postoperatively . Patients with severe pain with a simple knee range-of-motion test prior to TKA had a 10 times higher likelihood of moderate to severe pain at 6 months . A simple test of pain intensity with active flexion and extension preoperatively was a significant predictor of postoperative pain at 6 months after surgery . Strategies to address this particular patient group may improve satisfaction rates of TKA ABSTRACT The primary objective of the present study was to examine the role of pain‐related psychological factors in predicting pain and disability following Total Knee Arthroplasty ( TKA ) . The study sample consisted of 75 ( 46 women , 29 men ) individuals with osteoarthritis of the knee who were scheduled for TKA .  Measures of pain severity , pain catastrophizing , depression , and pain‐related fears of movement  were completed prior to surgery . Participants completed measures of pain severity and self‐reported disability 6 weeks following surgery . Consistent with previous research , cross‐sectional analyses revealed significant correlations among measures of pre‐surgical pain severity , pain catastrophizing , depression and pain‐related fears of movement . Prospect i ve analyses revealed that pre‐surgical pain severity and pain catastrophizing were unique predictors of post‐surgical pain severity ( 6‐week follow‐up ) . Pain‐related fears of movement were predictors of post‐surgical functional difficulties in univariate analyses , but not when controlling for pre‐surgical co‐morbidities ( e.g. back pain ) . The results of this study add to a growing literature highlighting the prognostic value of psychological variables in the prediction of post‐surgical health outcomes . The results support the view that the psychological determinants of post‐surgical pain severity differ from the psychological determinants of post‐surgical disability . The results suggest that interventions design ed to specifically target pain‐related psychological risk factors might improve post‐surgical outcomes Summary Patients ’ behavioral outcome expectancies assessed presurgically predicted pain severity and physical function 1 year after total knee arthroplasty ( TKA ) and partially mediated the relation between catastrophizing and TKA outcomes . Abstract The present study examined the prospect i ve value of response expectancies ( ie , pain , sleep ) and behavioral outcome expectancies ( ie , return to function ) in the prediction of pain severity and functional limitations 12 months after total knee arthroplasty ( TKA ) . The study sample consisted of 120 individuals ( 73 women , 47 men ) with osteoarthritis of the knee who were scheduled for TKA .  Measures of expectancies , pain severity , pain catastrophizing , pain‐related fears of movement , and depression  were completed prior to surgery . Participants also completed measures of pain severity and functional limitations 12 months following surgery . Analyses revealed that behavioral outcome expectancies were stronger predictors of follow‐up pain and functional limitations than response expectancies . Consistent with previous research , analyses also revealed that pain catastrophizing , pain‐related fear of movement , and depression predicted follow‐up pain and function . In a multivariate analysis , only pain catastrophizing contributed significant unique variance to the prediction of follow‐up pain and function . Behavioral outcome expectancies partially mediated the relation between catastrophizing and follow‐up pain and function . The relation between catastrophizing and follow‐up pain severity and functional limitations remained significant even when controlling for behavioral outcome expectancies . The results suggest that interventions design ed to specifically target behavioral outcome expectancies and catastrophizing might improve post‐surgical outcomes
target: This study provides moderate-level evidence for pain catastrophizing as an independent predictor of chronic pain post-TKA .
background: BACKGROUND Total knee arthroplasty ( TKA ) is a common and costly surgical procedure .
  Despite high success rates , many TKA patients develop chronic pain  in the months and years following surgery , constituting a public health burden .
  Pain catastrophizing is a construct that reflects anxious preoccupation with pain , inability to inhibit pain-related fears , amplification of the significance of pain vis-à-vis health implication s , and a sense of helplessness regarding pain .
  Recent research suggests that it may be an important risk factor for untoward TKA outcomes .
  To clarify this impact , we systematic ally review ed the literature to date on pain catastrophizing as a prospect i ve predictor of chronic pain following TKA .