Risk Factors For Chronic Pain Research Articles

Chronic Pain and Associated Factors in India and Nepal: A Pilot Study of the Vanderbilt Global Pain Survey.

Evaluation and treatment of chronic pain worldwide are limited by the lack of standardized assessment tools incorporating consistent definitions of pain chronicity and specific queries of known social and psychological risk factors for chronic pain. The Vanderbilt Global Pain Survey (VGPS) was developed as a tool to address these concerns, specifically in the low- and middle-income countries where global burden is highest. The VGPS was developed using standardized and cross-culturally validated metrics, including the Brief Pain Inventory and World Health Organization Disability Assessment Scale, as well as the Pain Catastrophizing Scale, the Fibromyalgia Survey Questionnaire along with queries about pain attitudes to assess the prevalence of chronic pain and disability along with its psychosocial and emotional associations. The VGPS was piloted in both Nepal and India over a 1-month period in 2014, allowing for evaluation of this tool in 2 distinctly diverse cultures. Prevalence of chronic pain in Nepal and India was consistent with published data. The Nepali cohort displayed a pain point prevalence of 48%-50% along with some form of disability present in approximately one third of the past 30 days. Additionally, 11% of Nepalis recorded pain in 2 somatic sites and 39% of those surveyed documented a history of a traumatic event. In the Indian cohort, pain point prevalence was approximately 24% to 41% based on the question phrasing, and any form of disability was present in 6 of the last 30 days. Of the Indians surveyed, 11% reported pain in 2 somatic sites, with only 4% reporting a previous traumatic event. Overall, Nepal had significantly higher chronic pain prevalence, symptom severity, widespread pain, and self-reported previous traumatic events, yet lower reported pain severity. Our findings confirm prevalent chronic pain, while revealing pertinent cultural differences and survey limitations that will inform future assessment strategies. Specific areas for improvement identified in this VGPS pilot study included survey translation methodology, redundancy of embedded metrics and cultural limitations in representative sampling and in detecting the prevalence of mental health illness, catastrophizing behavior, and previous traumatic events. International expert consensus is needed.

What are the influencing factors for chronic pain following TAPP inguinal hernia repair: an analysis of 20,004 patients from the Herniamed Registry

BackgroundIn inguinal hernia repair, chronic pain must be expected in 10–12% of cases. Around one-quarter of patients (2–4%) experience severe pain requiring treatment. The risk factors for chronic pain reported in the literature include young age, female gender, perioperative pain, postoperative pain, recurrent hernia, open hernia repair, perioperative complications, and penetrating mesh fixation. This present analysis of data from the Herniamed Hernia Registry now investigates the influencing factors for chronic pain in male patients after primary, unilateral inguinal hernia repair in TAPP technique.MethodsIn total, 20,004 patients from the Herniamed Hernia Registry were included in uni- and multivariable analyses. For all patients, 1-year follow-up data were available.ResultsMultivariable analysis revealed that onset of pain at rest, on exertion, and requiring treatment was highly significantly influenced, in each case, by younger age (p < 0.001), preoperative pain (p < 0.001), smaller hernia defect (p < 0.001), and higher BMI (p < 0.001). Other influencing factors were postoperative complications (pain at rest p = 0.004 and pain on exertion p = 0.023) and penetrating compared with glue mesh fixation techniques (pain on exertion p = 0.037).ConclusionsThe indication for inguinal hernia surgery should be very carefully considered in a young patient with a small hernia and preoperative pain.

Somatoform and Affective Disorders in Chronic Pain: Temporary Sequence and Associated Factors

Pain is a multidimensional experience encompassing both sensory and emotional elements. There are many factors involved in the etiopathogenesis, evolution and maintenance of chronic pain, with psychopathological factors being important. According to the results of this study, it is frequent to suffer psychopathology prior to the painful process, which is a risk factor for chronic pain, and in time, it becomes the center of life of the patients, changing the diagnosis to Somatoform Disorder.

Persistent postherniorrhaphy pain following inguinal hernia repair: A cross-sectional study of prevalence, pain characteristics, and effects on quality of life

IntroductionChronic inguinal pain due to the inguinal hernia repair is still a serious consideration, and its incidence is evident in approximately 3%–6% of the patients. The purpose of this study was performed to assess the prevalence of chronic pain after inguinal hernia repair and the effects on the quality of life in our patient. MethodsThe records of the patients who were 18 years of age or older and had had an inguinal hernia repair under spinal anesthesia after receiving a diagnosis of inguinal hernia at this hospital from 2009 to 2015 were accessed through the hospital's data system. Patients who had signed the informed consent agreement were given an Inguinal Pain Questionnaire (IPQ) and a Douleur Neuropathique 4 (DN-4) questionnaire after recording their demographic data on the appointment day. Surgical incision line was evaluated with a dolorimeter and mild touch hypoesthesia, needle-touch hypoesthesia, brushing allodynia were evaluated with cotton, and 0.711 mm diameter Von-Frey filament (Touch-Test Sensory Evaluator Kit; North Coast Medical, Inc., Gilroy, CA, USA). ResultsThe total number of patients who had ASA I-II scores and who had undergone a one-sided inguinal hernia repair under spinal anesthesia in elective conditions with at least three or more months of recovery time months was 619. Of these 264 patients, 203 with absence of pain (score of the severest pain over the past week and now was 0) were classified as the Non-Pain group and 61 patients with inguinal pain (score of the severest pain over the past week or now was 1 or more) were classified as the Pain group.The incidence of chronic pain after inguinal hernia surgery was 23.48% (n = 61) in our study. The pain was localized at and near the surgical incision and radiated into the scrotum in 17.73% (n = 36) of the male patients having chronic pain. While chronic pain developed in 60 out of 239 patients who had pain prior to the surgery. The presence of pain prior to the surgery was evaluated as an effective factor for the chronic groin pain. Neuropathic pain was detected with the DN-4 questionnaire in 6 (2.95%) out of 203 patients who stated that they had no pain during the physical examination and the week prior to the exam. The frequency of chronic pain after inguinal hernia repair was found 23.48% in our study. This is the same rate as previously reported. Quality of life of these patients was affected. We believe that there is an urgent need for prospective randomized studies with the aim of determining a standardized methodology towards preventive measures after determining the risk factors of chronic pain developed in the post inguinal hernia repair period.

Incidence and risk factors of chronic pain following hysterectomy among Southern Jiangsu Chinese Women

BackgroundChronic post-surgical pain (CPSP) after hysterectomy has been recognized as a major clinical problem in the Western World. Reports on post-hysterectomy pain are relatively scarce in China. The aim of the current study was to prospectively investigate the incidence and the potential risk factors of CPSP at 3 months following hysterectomy in Chinese population.MethodsWe assessed and collected data on preoperative socio-demographic characteristics, preexisting pain, anxiety and depression, sexual satisfaction, intra-operative variables, and acute postoperative pain intensity in a cohort of 870 women undergoing hysterectomy. The participants were interviewed to determine their suitability to diagnostic criteria of CPSP 3 months later. Logistic regression analyses were subsequently performed to identify predictors for CPSP.ResultsThe incidence of CPSP at 3 months after hysterectomy was 27.7%. Most of the women with CPSP suffered from mild pain and had a slight impact on daily life with sleep and emotion functional limitation. Risk factors for CPSP after hysterectomy were preoperative anxiety, depression, pelvic pain, preexisting pain, very-moderate sexual dissatisfaction, and acute postoperative pain at movement. Intra-operative dexmedetomidine infusion with 0.5 μg/kg/h was associated with a decreased incidence rate of chronic post-hysterectomy pain.ConclusionTwenty-eight percent of patients after hysterectomy in southern Jiangsu china had CPSP with 92% of those women describing it as mild with sleep and emotion functional limitation. Patients with preoperative anxiety and depression, poor sexual satisfaction, preexisting pain, and acute postoperative pain on movement have been identified to be at risk to develop CPSP.

Pain sensitivity and analgesic use among 10,486 adults: the Troms\xf8 study

BackgroundIncreased pain sensitivity is a putative risk factor for chronic pain and consequently for analgesic use. Conversely, analgesic use may be a cause of increased pain sensitivity, e.g., through opioid-induced hyperalgesia. We aimed to study the association between pain sensitivity and analgesic use in a general population, and to test the hypothesis that increased baseline pain sensitivity is a risk factor for future persistent analgesic use.MethodsThe Tromsø Study (2007–08), a population-based health study, was linked with eight years of prescription data from the Norwegian Prescription Database. The cold pressor test was completed in 10,486 participants aged 30+ years, and we used cold pressor endurance time as a proxy measure of pain sensitivity. Cross-sectional associations with different measures of analgesic use were assessed. Furthermore, a cohort of 9,657 persons was followed for 4.5 years.ResultsIn the cross-sectional analysis, increased pain sensitivity was associated with analgesic use; regular users of opioids alone were more pain sensitive than regular users of non-opioid analgesics. Increased baseline pain sensitivity was a risk factor for persistent analgesic use, i.e., using non-steroidal anti-inflammatory drugs, paracetamol, or opioids for ≥ 90 days and proportion-of-days-covered ≥ 40% (HR = 1.22, 95% CI 1.06-1.40), although not statistical significant after confounder adjustment.ConclusionsIncreased pain sensitivity was associated with analgesic use in general, and reduced pain tolerance was found for both opioid and non-opioid analgesic users. The data suggest that hyperalgesia is an effect of analgesics, whereas pain tolerance has little impact on future analgesic use.

Risk factors of chronic pain after inguinal hernia repair: a systematic review.

IntroductionChronic postoperative inguinal pain (CPIP) is the most common complication after inguinal hernia operation. Eighteen percent (range, 0.7%–75%) of patients suffered from CPIP after open inguinal hernia repair and 6% (range, 1%–16%) reported CPIP after laparoendoscopic groin hernia repair. The incidence of clinically significant CPIP with impact on daily activities ranged between 10% and 12%. Debilitating CPIP with severe impact on normal daily activities or work was reported in 0.5%–6% of the cases.Materials and methodsPubMed, Medline, Embase, and the Cochrane Database were searched for studies on risk factors for chronic pain after open and endoscopic hernia repair. A systematic review of the literature was conducted using the grading of recommendations, assessment, development, and evaluations (GRADE) methodology.ResultsRisk factors for CPIP with strong evidence include female gender, young age, high intensity of preoperative pain, high early postoperative pain intensity, history of chronic pain other than CPIP, operation for a recurrent hernia, and open repair technique. Risk factors for CPIP with moderate evidence include postoperative complications, neurolysis, and preservation of the ilioinguinal nerve in Lichtenstein repair. Risk factors for CPIP with low evidence include genetic predisposition (DQB1*03:02 HLA haplotype), lower preoperative optimism, high pain intensity to tonic heat stimulation, inadequate suture/staple/clip mesh fixation, ignorance of the inguinal nerves, less experienced surgeon, sensory dysfunction in the groin, and worker’s compensation.ConclusionDetailed knowledge of the risk factors, meticulous operative technique with profound knowledge of the anatomy, proper nerve identification and handling, optimization of prosthetic materials, and careful fixation are of utmost importance for the prevention of CPIP.

Study of chronic pain and its associated risk factors among Japanese industry workers: the Quality of Working Life Influenced by Chronic pain (QWLIC) study.

This study was performed to identify the prevalence, influence, and risk factors associated with chronic pain among Japanese industry workers. We investigated 2,544 participants working at a manufacturing company A, a manufacturing company B, and 16 branch shops of a retail chain company C. The participants responded to self-administered questionnaires related to pain. Furthermore, data obtained from the lifestyle interview sheet of an annual health screening examination and those obtained from the questionnaires were merged. We analyzed the association between lifestyles, psychosocial factors, and chronic pain. Age- and sex-adjusted odds ratios were calculated with a 95% confidence interval using the logistic regression model. Of 2,544 participants, 1,914 (1,224 men and 690 women) completed the questionnaire, and the response rate was 75.2%. The prevalence of chronic pain over 3 months was 42.7% and that of chronic pain with work disability was 11.3%. A higher proportion of obesity, smoking habit, insomnia, psychological stress, depressive state, workaholic nature, low social support from supervisors and coworkers, high job demand, low job control, and job dissatisfaction was observed in workers with chronic pain than in workers without pain. Several risk factors of chronic pain in Japanese industry workers were found. Obesity, smoking habits, sleep disorders, workplace environment, and mental state should be taken into account as risk factors associated with chronic pain issues and general occupational health.

Acute Pain Characteristics in Patients with and without Chronic Pain following Lower Extremity Injury

Many patients with injuries to lower extremities report chronic pain. High pain intensity at time of admission for injury is a risk factor for chronic pain, but it is not clear whether specific acute pain patterns following injury influence the development of chronic pain. To examine the relationship between the pain trajectory, the mean pain score, and the frequency of pain documentation during the immediate hospitalization following injury, with the report of chronic pain. This was a descriptive, retrospective cohort study of adults admitted with lower extremity fractures to an academic urban trauma center. Participants, 6-45 months postinjury, rated their current pain, worst pain, and average pain over the last 3 months. Pain scores from hospitalization associated with the injury were obtained through a retrospective chart review. The pain trajectory, mean pain score, and frequency of pain documentation was compared between patients with and without chronic pain. A total of 129 patients were enrolled in this study and 78% reported chronic pain at the site of injury. The mean pain score (5.1 vs. 4.2) and first pain score (5.6 vs. 3.4) were higher for patients with chronic pain compared to patients with no chronic pain. Consistent with other studies, high pain intensity at time of injury was associated with chronic pain. The findings contribute valuable information about acute pain characteristics associated with chronic pain and provide insight into the importance of early and adequate acute pain treatment.

The patient-reported outcome of chronic pain after the harvest of anterior iliac bone for anterior cervical arthrodesis

BackgroundAnterior cervical fusion (ACF) with autologous iliac bone graft is a traditional surgical method, but high rate of chronic pain (30%) at the anterior iliac crest presents a considerable hindrance to harvesting iliac bone. The memory of acute pain may become fainter as time progresses, and the incidence of chronic pain may not be as high as previously reported. The primary objective was to show the patient-reported outcome of chronic pain in the anterior iliac crest. MethodsTelephone surveys were conducted for patients with single-level ACF (group-S; n=72; M:F=52:20; median age, 53years), multiple-level ACF (group-M; n=61; M:F=40:21; 56years) using autologous iliac bone, and single-level ACF with a stand-alone cage (group-C; n=53; M:F=38:15; 51years). Logistic regression analysis was performed to determine the risk factors, and the variables included group, age, gender, postoperative period and satisfaction with the surgical outcome. ResultsThere was no chronic pain in 87% of the patients, with no difference among the groups (p=0.52). During the acute postoperative period, patients remembered no pain in 38/72 (53%) patients of group-S, 25/61 (41%) of group-M and 42/53 (79%) of group-C (p<0.001). Female gender (p=0.027; OR, 2.68; 95% CI, 1.12–6.41) was the risk factor for chronic pain. ConclusionsIliac bone harvest may not cause chronic pain in 87% of patients, and the memory of acute pain was faded in 40–50% of patients. Female gender was a risk factor for chronic pain. This information should be considered before harvesting iliac bone.

Prevalence and risk factors for chronic pain following cesarean section: a prospective study.

BackgroundChronic post-surgical pain (CPSP) remains a major clinical problem which may be associated with impaired activities of daily life and decreased health-related quality of life. Although cesarean section is one of the most commonly performed operations, chronic pain after cesarean delivery has not been well-studied. The purpose of this prospective study was to assess the incidence and risk factors of chronic pain at 3, 6 and 12 months after cesarean delivery.MethodsWe prospectively investigated preoperative demographic and psychological factors, intraoperative clinical factors, and acute postoperative pain in a cohort of 527 women undergoing cesarean section. The women were interviewed and completed pain questionnaires after 3, 6 and 12 months. Questions were about pain intensity, frequency, and location, as well as medical treatment and impact on daily living.ResultsThe incidence of CPSP at 3, 6 and 12 months after cesarean section was 18.3 %, 11.3 % and 6.8 %, respectively. Most of the women with CPSP experienced mild pain at rest. The incidence of moderate and severe pain on movement was high at 3 month, and then has a significant decrease at 6 and 12 months. CPSP had a negative influence on the activities of daily living. Independent predictors of CPSP at 3 months included higher average pain intensity on movement within 24 h postoperatively, preoperative depression, and longer duration of surgery. At 6 months, more severe pain during movement within 24 h of surgery and preoperative depression were predictive of pain persistence. And 12 months after surgery, only higher average pain score on movement within 24 h following cesarean section was found to be significant associated with CPSP. The three models all showed moderate discrimination and good calibration for the prediction of CPSP at 3, 6 and 12 months postoperatively.ConclusionsCPSP was not rare in women undergoing cesarean section. Patients with more intense of acute postoperative pain on movement, preoperative depression, and longer surgical time had greater risk for CPSP following surgery.Electronic supplementary materialThe online version of this article (doi:10.1186/s12871-016-0270-6) contains supplementary material, which is available to authorized users.

Constitutional features of connective tissue as a risk factor of chronic pain in adolescents

A total of 504 male adolescents aged 14-18, cadet schools students were examined to identify primary head pain and functional abdominal pain. A 4-stage-blind clinical laboratory and case-control psychological examination, in which are formed two groups: basic - 90 boys with primary head pain and functional abdominal pain, and 93 healthy children (control group). Total number of teens with headaches was 76 (48 isolated headaches and 28 - headaches in conjunction with abdominal pain). The number of cadets with abdominal pain was 42, 14 was manifested monosemeiotic and 28 - in conjunction with headaches. Complex research revealed pathogenetic common primary headaches and functional abdominal pain, to identify risk factors for their development. The analysis of the results of complex examination adolescents univariate statistics significant association features of the connective tissue with the presence of primary headache, especially in combination with functional abdominal pain. Obtained significant differences in many biological, psychological and social characteristics. This fact indicates eligibility review genesis of functional disorders with painful symptoms in adolescents from the perspective of the biopsychosocial model. The present results indicate the importance of the state of the connective tissue as an essential component of the formation of predisposition to chronic pain. Other predictors of pain were advancing sexual development, emotional instability, additional sports classes.

Construct validity and reliability of Finnish version of Örebro Musculoskeletal Pain Screening Questionnaire

IntroductionChronic pain causes suffering for affected individuals and incurs costs to society through work disability. Interventions based on early screening of psychological risk factors for chronic pain using screening tools such as the Örebro Musculoskeletal Pain Screening Questionnaire (ÖMPSQ) have been found to reduce work absenteeism and health care visits and increase perceived health. The aim of the current study was to translate the ÖMPSQ into Finnish and test its validity and reliability in a patient sample. MethodsThe ÖMPSQ was forward–backward translated and cross-culturally adapted, and applied to our study population (n=69), the members of which had been referred to the Department of Physical and Rehabilitation Medicine of Oulu University Hospital from primary health care centres in Northern Finland due to chronic low back pain. The patients answered the ÖMPSQ two weeks before the hospital visit, and the follow-up questionnaire either during the hospital visit, or after by mail. The reliability of the ÖMPSQ was evaluated using intraclass correlation coefficients (ICC). Factor analysis was used to group items of the ÖMPSQ, and internal consistency between the items was determined by calculating Cronbach's alphas. ResultsThe cross-cultural adaptation revealed only minor semantic and cultural differences. Measurements showed reliability as moderate to nearly perfect for all of the ÖMPSQ items (ICC values ranged from 0.59 to 0.96). Items loaded into five different factors: disability, psychological symptoms, pain, fear avoidance, and work. All except one (work) showed acceptable internal consistency. The ÖMPSQ score was positively associated with both intensity of pain and the Oswestry Disability Index. Conclusions and implicationsThe reliability and construct validity of the Finnish version of the ÖMPSQ were good. The predictive ability of the ÖMPSQ in the Finnish population should be evaluated in further studies.

Impact of Mesh Fixation on Chronic Pain in Total Extraperitoneal Inguinal Hernia Repair (TEP): A Nationwide Register-based Study.

Mesh fixation is used to prevent recurrence at the potential risk for chronic pain in TEP. The aim was to compare the impact of permanent fixation (PF) with no fixation (NF)/nonpermanent fixation (NPF) of mesh on chronic pain after TEP repair for primary inguinal hernia. Men, 30 to 75 years old, consecutively registered in the Swedish Hernia Register for a TEP primary repair in 2005 to 2009, were included in a mail survey using SF-36 and the Inguinal Pain Questionnaire (IPQ). Primary endpoint was IPQ question "Did you have pain during past week that could not be ignored." Risk factors for chronic pain and recurrent operations were analyzed. A total of 1110 patients were included (325 PF, 785 NF/NPF) with 7.7% reporting pain at median 33 months follow-up. No difference regarding primary endpoint pain (P < 0.462), IPQ and SF-36 subscales were seen. Recurrent operation was carried out in 1.4% during 7.5 years follow-up with no difference between PF- and NF-groups including subgroups of medial hernias. All SF-36 subscale-scores were equal to or better than the Swedish norm. A postoperative complication was a risk factor for chronic pain (OR 2.44, 95% CI 1.23-5.25, P < 0.023). The TEP procedure for primary inguinal hernia repair in men is associated with a low frequency of chronic pain and recurrent operations, with no difference between permanent fixation and no/nonpermanent fixation of mesh in a nationwide population-based study. TEP without fixation reduces costs and is safe for all patients.

Traumatic Exposure History as a Risk Factor for Chronic Pain in Adult Patients with Sickle Cell Disease.

This article describes the impact of the integration of a licensed clinical social worker (LCSW) with expertise in behavioral health on identification of risk factors for chronic pain in a cohort of adults with sickle cell disease. Authors conducted a retrospective chart review of all visits to the adult sickle cell center during the first six months of LCSW integration. Demographics, clinical history, and LCSW notes were reviewed. Overall, 71 patients were introduced to the LCSW; 55 percent of them had chronic pain. Patients with chronic pain were older, used opioids daily, took hydroxyurea, reported higher daily pain scores, and underwent more acute care visits and hospitalizations for pain with longer stays. Fifty-eight (81 percent) patients requested concrete social work services such as transportation and housing. Thirty-two patients (55 percent) expressed a desire for mental health counseling while receiving concrete services. Twenty-two (69 percent) of these patients self-disclosed at least one traumatic experience. In fact, a statistically significant relationship between chronic pain and a history of trauma was identified (p = 0.001). Results suggest that sickle cell patients should receive clinical social work services to assess for traumatic exposures that may influence chronic pain.

The Association between Chronic Widespread Musculoskeletal Pain, Depression and Fatigue Is Genetically Mediated.

BackgroundChronic widespread muscoloskeletal pain (CWP) is prevalent in the general population and associated with high health care costs, so understanding the risk factors for chronic pain is important for both those affected and for society. In the present study we investigated the underlying etiological structure of CWP to understand better the association between the major clinical features of fatigue, depression and dihydroepiandrosterone sulphate (DHEAS) using a multivariate twin design.Methodology/Principle FindingsData were available in 463 UK female twin pairs including CWP status and information on depression, chronic fatigue and serum DHEAS levels. High to moderate heritabilities for all phenotypes were obtained (42.58% to 74.24%). The highest phenotypic correlation was observed between fatigue and CWP (r = 0.45), and the highest genetic correlation between CWP and fatigue (rg = 0.78). Structural equation modeling revealed the AE Cholesky model to provide the best model of the observed data. In this model, two additive genetic factors could be detected loading heavily on CWP—A2 explaining 40% of the variance and A3 20%. The factor loading heaviest on DHEAS showed only a small loading on the other phenotypes and none on fatigue at all. Furthermore, one distinct non-shared environmental factor loading specifically on CWP—but not on any of the other phenotypes—could be detected suggesting that the association between CWP and the other phenotypes is due only to genetic factors.Conclusions/SignificanceOur results suggest that CWP and its associated features share a genetic predisposition but that they are relatively distinct in their environmental determinants.

Validation of a Simplified Chinese Version of the Pain Catastrophizing Scale and an Exploration of the Factors Predicting Catastrophizing in Pain Clinic Patients

Background: Chronic pain is very common worldwide and can lead to disability, depression and absence from work. Catastrophizing has been proven to affect individuals’ belief systems and coping strategies, and it is an essential risk factor for chronic pain. The pain catastrophizing scale (PCS) has been developed for the assessment of catastrophizing. However, a Chinese version of this scale is not available, and physicians are therefore unable to determine which patients are prone to catastrophizing. Additionally, the risk factors for catastrophizing are unknown. Objective: We aimed to cross-culturally adapt and validate the PCS for simplified Chinese (SCPCS) and explore the risk factors for catastrophizing in patients from a pain clinic. Study Design: We utilized a prospective, nonrandomized, cross-sectional, descriptive survey design. A second analysis of test-retest reliability was performed in a longitudinal, observational study. Setting: A convenience sample was recruited from a pain clinic in a tertiary hospital. Methods: This study was performed in 3 stages. In the first stage, the PCS was translated and culturally adapted to create a Chinese version; in the second stage, the measurement properties of the SC-PCS were tested, including the content validity, construct validity and reliability; and in the third stage, factors affecting catastrophizing in a pain clinic setting were explored. The adaptation was performed using a forward-backward method, and content validity was analyzed by examining the response trend (Z-skewness and item-total correlation). Construct validity was analyzed by assessing structural validity (confirmatory factor analysis [CFA] and exploratory factor analysis [EFA]) and a priori hypothesis testing. Reliability was analyzed by internal consistency (Cronbach’s alpha) and test-retest reliability (intraclass correlation coefficient [ICC]). Risk factors for catastrophizing were analyzed by multivariate linear regression. Results: A total of 153 patients were included, with a response rate of 96%; no items were excluded from the SC-PCS. Both CFA and EFA confirmed a 3-factor structure, and 9/10 of the hypotheses were verified for construct validity. Excellent reliability was acquired with a Cronbach’s alpha of 0.91, and an ICC of 0.94 was determined. Risk factors for catastrophizing included college education (beta = 0.47), pain duration (beta = 0.40), female (beta = 0.31), freelancer status (beta = 0.31), and retired status (beta = 0.19). Limitations: The recruited patients experienced severe pain or long-duration pain in a pain clinic setting. This may limit the applicability of the SC-PCS to patients with low or moderate pain levels. Conclusion: The PCS has been linguistically translated into simplified Chinese and culturally adapted for a Chinese population with remarkable clinical acceptance, good construct validity, and excellent internal consistency and test-retest reliability. Education, pain duration, marital status, gender, income, and use of pain medications are important factors affecting catastrophizing. Key words: Chronic pain, catastrophizing, HADS, SF-12, BPI, risk factor, reliability, validity

Characteristics of Patients with Lower Extremity Trauma with Improved and Not Improved Pain During Hospitalization: A Pilot Study

Up to 62% of patients report chronic pain at the injury site 6-12 months after blunt trauma, with pain from lower extremity fractures exceeding that from other sites. High pain intensity at time of injury is a risk factor for chronic pain, but it is not clear what patient characteristics influence the pain intensity level during the immediate hospitalization following injury. The purpose of this pilot study was to determine the feasibility of collecting pain scores from medical records to calculate pain trajectories and to determine whether it is possible to examine patient characteristics by classifying them into those whose pain improved and those whose pain did not improve. This descriptive study retrospectively reviewed medical records of 18 randomly chosen patients admitted to an academic trauma center. Patient characteristics and pain scores were collected form electronic and handwritten medical records. The pain trajectories calculated from routinely collected pain scores during the inpatient stay showed that for 44% of patients the pain improved during the hospitalization, for 39% the pain remained the same, and for 17% the pain worsened. The variables age, smoking, weight, abbreviated injury scores, length of hospital stay, mean pain score, and opioid equianalgesic dose differed based on pain trajectory. While patient characteristics differed based on pain trajectory, any significant effects seen from individual tests should be considered tentative, given the number of analyses conducted on this data set. However, feasibility and significance of conducting a larger study has been established.

Long-term Results After Ankle Syndesmosis Injuries.

Syndesmotic disruption occurs in more than 10% of ankle fractures. Operative treatment with syndesmosis screw fixation has been successfully performed for decades and is considered the gold standard of treatment. Few studies have reported the long-term outcomes of syndesmosis injuries. This study investigated long-term patient-reported, radiographic, and functional outcomes of syndesmosis injuries treated with screw fixation and subsequent timed screw removal. A retrospective cohort study was carried out at a Level I trauma center. The study group included 43 patients who were treated for ankle fractures with associated syndesmotic disruptions between December 2001 and May 2011. The study included case file reviews, self-reported questionnaires, radiologic reviews, and clinical assessments. At 5.1 (±1.76) years after injury, 60% of participants had pain, 26% had degenerative changes, 51% had loss of tibiofibular overlap, and 33% showed medial clear space widening. Retained syndesmotic positions on radiographs were linked to better self-reported outcomes. There is an inversely proportional relation between age at the time of injury and satisfaction with the outcome of the ankle fracture as well as a directly proportional relation between age at the time of injury and pain compared with the preinjury state. Optimal restoration and preservation of the syndesmosis is crucial. Syndesmotic disruption is associated with poor long-term outcomes after ankle fracture. Greater age is a risk factor for chronic pain and dissatisfaction with the outcome of ankle fracture and syndesmosis injury. Therefore, patient education to facilitate realistic expectations about recovery is vital, especially in older patients.

Pain after total knee arthroplasty: a narrative review focusing on the stratification of patients at risk for persistent pain.

The patient with a painful arthritic knee awaiting total knee arthroplasty (TKA) requires a multidisciplinary approach. Optimal control of acute post-operative pain and the prevention of chronic persistent pain remains a challenge. The aim of this paper is to evaluate whether stratification of patients can help identify those who are at particular risk for severe acute or chronic pain. Intense acute post-operative pain, which is itself a risk factor for chronic pain, is more common in younger, obese female patients and those suffering from central pain sensitisation. Pre-operative pain, in the knee or elsewhere in the body, predisposes to central sensitisation. Pain due to osteoarthritis of the knee may also trigger neuropathic pain and may be associated with chronic medication like opioids, leading to a state of nociceptive sensitisation called 'opioid-induced hyperalgesia'. Finally, genetic and personality related risk factors may also put patients at a higher risk for the development of chronic pain. Those identified as at risk for chronic pain would benefit from specific peri-operative management including reduction in opioid intake pre-operatively, the peri-operative use of antihyperalgesic drugs such as ketamine and gabapentinoids, and a close post-operative follow-up in a dedicated chronic pain clinic.