Cross-cultural adaption, validity, and reliability of the Japanese version of the Central Aspects of Pain in the Knee (CAP-Knee-J) questionnaire in patients with knee pain: a validation study.

BACKGROUND: Knee pain is a prominent concern among older individuals, influenced by the central nervous system. This study aimed to translate the Central Aspects of Pain in the Knee (CAP-Knee) questionnaire into Japanese and investigate its reliability and validity in older Japanese individuals with knee pain. METHODS: Using a forward-backward method, CAP-Knee was translated into Japanese, and data from 110 patients at an orthopedic clinic were analyzed. The Japanese version (CAP-Knee-J) was evaluated regarding pain intensity during walking, central sensitization inventory, and pain catastrophizing scale. Statistical analyses confirmed internal validity and test-retest reliability. Concurrent validity was assessed through a single correlation analysis between CAP-Knee-J and the aforementioned measures. Exploratory factor analysis was employed on each CAP-Knee-J item to examine structural validity. RESULTS: CAP-Knee-J showed good internal consistency (Cronbach's α = 0.86) and excellent test-retest reliability (intraclass correlation coefficient = 0.77). It correlated significantly with pain intensity while walking, central sensitization inventory scores, and pain catastrophizing scale scores. Exploratory factor analysis produced a three-factor model. CONCLUSIONS: CAP-Knee-J is a reliable and valid questionnaire for assessing central pain mechanisms specific to knee pain in older Japanese individuals, with moderate correlations with the CSI and weak with the PCS, thus indicating construct validity. This study supports the development of effective knee pain treatments and prognosis predictions.

Does a combination of self-reported signs related to central sensitization and pressure pain threshold allow for a more detailed classification of pain-related characteristics in patients with chronic musculoskeletal pain?: A cross-sectional study.

OBJECTIVES: The clinical utility of combining the central sensitization (CS) inventory (CSI) with the pressure pain threshold (PPT) in assessing the effect of central sensitization on pain is unknown. This study aimed to investigate the effects of CSI, PPT, and their interaction on pain and the characteristics of clinical symptoms in patients with chronic musculoskeletal pain grouped according to the CSI score and PPT value. METHOD: A total of 187 participants with chronic musculoskeletal pain were recruited. PPT, brief pain inventory, widespread pain index, pain catastrophizing scale, EuroQol-5 dimension, and CSI were assessed. Multiple regression analyses were performed using pain intensity and interference scores as dependent variables and the CSI score and PPT value as independent variables. Hierarchical cluster analysis was also performed to classify the participants into subgroups according to the CSI score and PPT value. Following the classification, pain-related characteristics and health-related QOL were compared among the subgroups. RESULTS: Multiple regression analyses demonstrated that only the CSI score significantly affected pain intensity and interference. As a result of the cluster analysis, three groups were identified: cluster 1 (n = 61, CSI low/PPT low group), cluster 2 (n = 78, CSI low/PPT high group), and cluster 3 (n = 48, CSI high/PPT low group). The CSI high/PPT low group had a higher incidence of pain-related symptoms than the CSI low group regardless of the PPT value. CONCLUSIONS: Combined CSI and PPT may not fully allow a detailed classification of pain-related characteristics. The CSI may be clinically more useful for assessing the effect of CS on pain-related symptoms.

Effect of perioperative pain neuroscience education in patients with post-mastectomy persistent pain: a retrospective, propensity score-matched study.

PURPOSE: Central sensitization (CS)-related symptoms and pain catastrophizing contribute to persistent post-mastectomy pain (PPMP). Pain neuroscience education (PNE) is effective in reducing CS-related symptoms and pain catastrophizing in patients with chronic pain. However, to date, no intervention study of PNE has been conducted to patients with PPMP. This study was aimed to examine whether PNE is more effective than biomedical education (BME) for PPMP. METHODS: In this retrospective case-control study, 118 patients were included. We intervened different patients at different times as follows: (1) a BME group (n = 58) of patients who received BME combined with physiotherapy and (2) a PNE group (n = 60) of patients who received PNE combined with physiotherapy. One year after surgery, we assessed pain intensity and interference (brief pain inventory [BPI]), CS-related symptoms (central sensitization inventory [CSI]), and pain catastrophizing (pain catastrophizing scale [PCS]). Propensity score matching was used to reduce or minimize selection bias and confounding biases and to make the number of cases in both groups match 1:1. RESULTS: Propensity score matching generated the BME group (n = 51) and the PNE group (n = 51). The BPI score, CSI score, and PCS score were statistically significantly lower in the PNE group than in the BME group (all, p < 0.05). The effect sizes for the BPI intensity (r = 0.31) were moderate. CONCLUSIONS: PNE resulted in a better outcome of pain management with less functional disability and CS-related symptoms compared to BME after breast surgery.

Validation of the Japanese version of the Bath CRPS Body Perception Disturbance Scale for CRPS.

PURPOSE: Body perception disturbance is a common symptom and may be one of the key targets of treatment intervention in complex regional pain syndrome (CRPS). As a comprehensive assessment tool of body perception in patients with CRPS, the Bath Body Perception Disturbance Scale (BPDS) was developed, and its adequate reliability and validity have been reported. However, there is no available Japanese version. Therefore, this study aimed to develop a Japanese version of BPDS (BPDS-J) and to investigate the validity of this scale in Japanese patients with CRPS. METHODS: We developed BPDS-J using a forward-backward method. We then assessed 22 patients with CRPS type 1 of the upper limb using BPDS-J, Brief Pain Inventory (BPI), Tampa Scale for Kinesiophobia (TSK), and a two-point discrimination threshold (TPD) on the middle finger. We investigated the internal consistency of BPDS-J and the correlation between BPDS-J and clinical outcomes as a concurrent validity measure. RESULTS: BPDS-J had good internal consistency (Cronbach's α = 0.73) and was significantly correlated with the TPD ratio (r = 0.65, adjusted p = 0.01) and TSK (r = 0.51, adjusted p = 0.04). CONCLUSIONS: BPDS-J has good internal consistency and concurrent validity for assessing body perception disturbance in Japanese patients with CRPS. Disturbed body perception may be worth evaluating when managing patients with CRPS using BPDS.

Combination of Pain Location and Pain Duration is Associated with Central Sensitization-Related Symptoms in Patients with Musculoskeletal Disorders: A Cross-Sectional Study.

OBJECTIVES: Increased evidence indicates that pain location affects central sensitization (CS)-related symptoms. In addition, pain location and pain duration may be intricately related to CS-related symptoms. However, these factors have been investigated separately. This study aimed to investigate the association between CS-related symptoms and pain location and/or pain duration in patients with musculoskeletal disorders. METHODS: Six hundred thirty-five participants with musculoskeletal disorders were included in this cross-sectional study. All participants were assessed for pain location, pain duration, central sensitization inventory (CSI), EuroQol-5 dimension, and brief pain inventory. The participants were categorized into 3 groups based on pain location (spinal, limb, and both spinal and limb pain) and into 2 groups based on pain duration (acute and chronic pain). RESULTS: The interaction between pain location and pain duration were not significant on CSI score (P > 0.05). The odds ratio for higher CSI score (≥ 40) in patients with both spinal and limb pain vs. those with spinal or limb pain was 2.64 (P < 0.01) and that in patients with chronic pain vs. those with acute pain was 1.31 (P = 0.52). In addition, the prevalence of higher CSI scores in the combination of chronic and "both spinal and limb" pain was high (23.1%, adjusted residual = 4.48). CONCLUSIONS: Pain location independently influenced CSI scores, and the combination of both spinal and limb pain and chronic pain indicated high CSI scores. The combination of pain location and pain duration is an important clue that points to CS-related symptoms.

Cutoff Value for Short Form of Central Sensitization Inventory.

OBJECTIVES: This study aimed to determine the optimal cutoff score of the 9-item short version of the CSI, the CSI-9, by comparing patients with central sensitivity syndrome (CSS) not only to healthy volunteers as with the original version, but also to patients with musculoskeletal (MSK) disorders. METHODS: All participants filled out the CSI, EuroQol 5-dimension, Brief Pain Inventory, and Pain Catastrophizing Scale questionnaires. To identify a clinically relevant cutoff score, receiver operating characteristic analyses were conducted. The area under the curve was used to examine the ability of the CSI-9 to distinguish patients with fibromyalgia (FM) from patients with MSK disorders and healthy individuals. RESULTS: Twenty-six participants with FM, 30 patients with MSK disorders, and 28 healthy individuals were included. We determined 2 cutoff scores: 20 for distinguishing patients with FM from patients with MSK disorders and 17 for distinguishing patients with FM from healthy individuals. These cutoff scores had good sensitivity (patients with MSK disorders, 92.3%; healthy individuals, 96.2%) and specificity (patients with MSK disorders, 93.3%; healthy individuals, 100%). In addition, the patients who scored above the cutoff of 20 points exhibited worse clinical symptoms (higher pain intensity, higher pain interference, higher Pain Catastrophizing Scale scores, and lower EuroQol 5-dimension scores) than those who scored below it. Furthermore, a significantly higher number of subjects who scored more than 20 on the CSI-9 had a history of 2 or more diagnoses of CSS. CONCLUSION: The optimal CSI-9 cutoff score of 20 is beneficial to clinicians in the evaluation of central sensitization-related symptoms. The cutoff score helps to identify patients who need additional treatments, such as pain neuroscience education and cognitive behavioral therapy.

Perceived Body Distortion Rather Than Actual Body Distortion Is Associated With Chronic Low Back Pain in Adults With Cerebral Palsy: A Preliminary Investigation.

OBJECTIVES: The aim of the present study was to investigate whether distorted body perception is a feature of the low back pain (LBP) experience in people with cerebral palsy (CP) and whether any distortions noted are confounded by the presence of motor and postural impairments commonly seen in CP. METHODS: Forty-five individuals participated in this study: 15 adults with CP with LBP (CP_Pain group), 15 adults with CP without LBP (CP_noPain group), and 15 age-matched adults with LBP but no CP (Pain group). Body perception was evaluated using the Fremantle Back Awareness Questionnaire (FreBAQ) and by assessing 2-point discrimination thresholds over the low back. A comprehensive assessment of motor function was also undertaken in the CP population, and postural function was assessed in all 3 groups. RESULTS: Significant differences between the 3 groups were found for FreBAQ scores (P < 0.0001). The TPD threshold in the low back of the CP_Pain group was significantly larger than that of the CP_noPain group (P = 0.01), though we found no difference between the CP_noPain group and the Pain group (P = 0.21). We found no difference in motor or postural function between the 2 CP groups. DISCUSSION: The present results suggest that body image is disrupted in people with CP who experience LBP. The disruptions in perception were similar to those seen in people with LBP and no CP, suggesting that the distortions may be more related to the presence of pain than the presence of CP.

Validation of the Japanese version of the life satisfaction checklist (LiSat-11) in patients with low back pain: A cross-sectional study.

BACKGROUND: Previous studies suggest that life satisfaction assessment using the Life Satisfaction checklist (LiSat-11) is a meaningful outcome measure and may play an important role in setting rehabilitation goals in patients with chronic pain. Until now, there was no Japanese version of this questionnaire, and the psychometric properties of the original version of the LiSat-11 have only been investigated using classical test theory approaches. The objective of the present study was to evaluate the psychometric properties of the LiSat-11-J using Rasch analysis in a sample of Japanese people with low back pain (LBP). METHODS: One hundred and two participants with LBP completed the LiSat-11-J. Concurrent Validity of the LiSat-11-J was investigated by examining the relationships between the LiSat-11-J and clinical valuable. Rasch analysis was used to assess targeting, category ordering, unidimensionality, person fit, internal consistency, and differential item functioning. RESULTS: The LiSat-11-J was significantly correlated with disability, pain-related catastrophizing, fear of movement, anxiety, and depression. The LiSat-11-J targeted the participants with low life satisfaction and had unidimensionality, good internal consistency, and good test-retest reliability. Responses to category 1 ("very dissatisfying") and 2 ("dissatisfying") were disordered. After collapsing these two categories into a single new category, targeting function and category order showed a little improvement. CONCLUSION: The LiSat-11-J has unidimensionality, acceptable internal consistency, good test-retest reliability, and concurrent validity to the assessment of pain-related disability and psychological factors. However, targeting function and category order were not well. These two components showed improvement by rescoring category, but not sufficient. These results suggest that the LiSat-11-J is not well adequate to apply as an assessment tool of life satisfaction to the patients with LBP.

Validation of the Japanese Version of the Fremantle Back Awareness Questionnaire in Patients with Low Back Pain.

BACKGROUND: There is a growing interest in the role of disturbed body perception in people with persistent pain problems such as chronic low back pain (CLBP). A questionnaire, the Fremantle Back Awareness Questionnaire (FreBAQ), was recently developed as a simple and quick way of assessing disturbed perceptual awareness of the back in people with CLBP and appears to have acceptable psychometric properties. The aim of the present study was to develop a Japanese version of the FreBAQ (FreBAQ-J) and evaluate its psychometric properties in a sample of Japanese people with low back pain (LBP). METHODS: Translation of the FreBAQ into Japanese was conducted using a forward-backward method. One hundred participants with LBP completed the resultant FreBAQ-J. A subset of the participants completed the FreBAQ-J again 2 weeks later. Validity was investigated by examining the relationship between the FreBAQ-J and clinical valuables. Rasch analysis was used to assess targeting, category ordering, unidimensionality, person fit, internal consistency, and differential item functioning. RESULTS: The FreBAQ-J was significantly correlated with pain in motion, disability, pain-related catastrophizing, fear of movement, and anxiety symptomatology. The FreBAQ-J had acceptable internal consistency, a minor departure from unidimensionality, and good test-retest reliability, and was functional on the category rating scale. CONCLUSIONS: The FreBAQ-J has acceptable psychometric properties and is suitable for use in people with LBP. Participants with high levels of disturbed body perception are well targeted by the scale. The functioning of one item (item 8) was poor. Further study is warranted to confirm if this item should be excluded.

Psychometric properties of the Japanese version of short forms of the Pain Catastrophizing Scale in participants with musculoskeletal pain: A cross-sectional study.

BACKGROUND: The Pain Catastrophizing Scale (PCS) is a commonly used as measure of pain catastrophizing. The scale comprises 13 items related to magnification, rumination, and helplessness. To facilitate quick screening and to reduce participant's burden, the four-item and six-item short forms of the English version of the PCS were developed. The purpose of the present study was to evaluate the psychometric properties of a Japanese version of the short forms of PCS using a contemporary approach called Rasch analysis. METHODS: A total of 216 patients with musculoskeletal disorders were recruited in this study. Participants completed study measures, which included the pain intensity, the Pain Catastrophizing Scale (PCS), and the Tampa Scale of Kinesiophobia (TSK). Furthermore, the four-item (items 3, 6, 8, and 11) and six-item (items 4, 5, 6, 10, 11, and 13) short forms of the Japanese version of PCS were measured. We used Rasch analysis to analyze the psychometric properties of the original, four-item, and six-item short forms of PCS. RESULTS: Rasch analysis showed that both short forms of PCS had acceptable internal consistency, unidimensionality, and no notable DIF and were functional on the category rating scale. However, four-item short form of PCS had two misfit items. CONCLUSIONS: Six-item short form of PCS has acceptable psychometric properties and is suitable for use in participants with musculoskeletal pain. Thus, six-item can be used as brief instruments to evaluate pain catastrophizing.

Successful Graded Mirror Therapy in a Patient with Chronic Deafferentation Pain in Whom Traditional Mirror Therapy was Ineffective: A Case Report.

A 43-year-old man had deafferentation pain in his right upper extremity secondary to brachial plexus avulsion from a traffic accident 23 years previously. On our initial examination, he had severe tingling pain with numbness in the right fingers rated 10 on the numerical rating scale. The body perception of the affected third and fourth fingers was distorted in the flexed position. Although he performed traditional mirror therapy (TMT) for 4 weeks in the same methods as seen in previous studies, he could not obtain willed motor imagery and pain-alleviation effect. Therefore, we modified the task of TMT: Graded mirror therapy (GMT). GMT consisted of five stages: (1) observation of the mirror reflection of the unaffected side without imagining any movements of the affected side; (2) observation of the mirror reflection of the third and fourth fingers changing shape gradually adjusted from a flexed position to a extended position; (3) observation of the mirror reflection of passive movement; (4) motor imagery of affected fingers with observation of the mirror reflection (similar to TMT); (5) motor imagery of affected fingers without mirror. Each task was performed for 3 to 4 weeks. As a result, pain intensity during mirror therapy gradually decreased and finally disappeared. The body perception of the affected fingers also improved, and he could imagine the movement of the fingers with or without mirror. We suggested that GMT starting from the observation task without motor imagery may effectively decrease deafferentation pain compared to TMT.

Effects of two different intensities of transcutaneous electrical nerve stimulation on pain thresholds of contralateral muscles in healthy subjects.

[Purpose] This study aimed to investigate the differential effects of high-intensity and low-intensity transcutaneous electrical nerve stimulation on the contralateral side on the pain threshold in healthy subjects. [Subjects and Methods] Twenty-five healthy adults, volunteers received two intensity levels (motor-level, 1.5 times the muscle motor threshold; sensory-level, sensory threshold of the common peroneal nerve), for 30 s on separate days. Pressure pain threshold was recorded on the contralateral tibialis anterior and deltoid muscle before, during, and after stimulation. [Results] Motor-level stimulation significantly increased the pressure pain threshold at both muscle sites, while effects of sensory-level stimulation on pressure pain thresholds were significant only at the deltoid site. The percent change in pressure pain thresholds at both sites was significantly higher during motor-level stimulation. [Conclusion] Motor-level stimulation, applied unilaterally to one leg, produced immediate contralateral diffuse and segmental analgesic effects. This may be of therapeutic benefit in patients for whom transcutaneous electrical nerve stimulation cannot be directly used at the painful site.

Social Network Moderates the Association between Frequency of Social Participation and Physical Function among Community-dwelling Older Adults.

OBJECTIVE: Social participation is an essential component of active aging. Physical dysfunction is restriction of social participation, but it is inconclusive that improvement of physical function contributes to promote social participation. Therefore, understanding the other factor that moderates the association between physical dysfunction and social participation is important, and social network (i.e., ties with family and friends) may be a key factor. The aims of this study were to investigate the association between physical function and frequency of social participation, with social network as a moderator, and to examine the gender differences on the relationships. METHODS: We conducted a cross-sectional study among 287 community-dwelling older adults. We asked how often they participated in social groups in a week to measure frequency of social participation. Physical function and social network were measured by using the modified version of Short Physical Performance Battery for community-dwelling older adults and the abbreviated Lubben Social Network Scale, respectively. To investigate the association, we performed a linear regression analysis. RESULTS: After adjustment, a linear regression analysis showed interactions between physical function and social network on frequent social participation (ß: -0.20, 95% confidence interval [CI]: -0.40 to -0.01). Furthermore, the same association was observed only in women (adjusted ß: -0.33, 95% CI: -0.65 to -0.02). CONCLUSION: Our results suggested that social network moderates the association between physical function and social participation, and observed gender differences on the relationships. The findings of this study indicated the importance of multidimensional assessment and measures for improving social participation, not only physical function but also social network.

Validation of the Japanese version of the patterns of activity measure-pain in individuals with chronic pain.

BACKGROUND: The Patterns of Activity Measure-Pain (POAM-P) is a self-report questionnaire that measures avoidance, overdoing, and pacing in individuals with chronic pain. We aimed to develop and confirm the psychometric properties of the Japanese version of the POAM-P(POAM-P-J) in Japanese individuals with chronic pain. METHODS: We recruited 147 Japanese individuals with chronic pain (106 women; mean age 64.89 ± 12.13 years). The individuals completed the POAM-P-J, the Brief Pain Inventory (BPI), and the Hospital Anxiety and Depression Scale (HADS). The following psychometric properties of the POAM-P-J were confirmed: structural validity, internal consistency, test-retest reliability, and concurrent validity. RESULTS: We tested factor structure via confirmatory factor analyses (CFA). We chose the 3-factor model with six covariances. The POAM-P-J's internal consistency and test-retest reliability were acceptable to good (α = 0.79-0.86; ICC = 0.72-0.87). The avoidance and overdoing subscales were positively associated with pain severity, pain interference, and anxiety measures (all p < 0.05), but the pacing subscale was not significantly associated with these pain-related measures. CONCLUSIONS: Although the structural validity of the POAM-P-J remains questionable, its internal consistency, test-retest reliability, and concurrent validity were confirmed. The POAM-P-J is useful in both research and clinical practice for evaluating the activity patterns of Japanese patients with chronic pain.

Effect of pain neuroscience education and exercise on presenteeism and pain intensity in health care workers: A randomized controlled trial.

OBJECTIVES: Decreased workforce productivity has a significant economic impact on healthcare systems. Presenteeism, the practice of working at reduced potential, is more harmful than absenteeism. Present workers most often experience musculoskeletal pain that is not mitigated by general exercise or stretching. We aimed to assess whether a regimen of pain neuroscience education (PNE) and exercise tailored to individual healthcare workers could reduce presenteeism and improve productivity. METHODS: An independent investigator randomized 104 medical professionals into two groups (intervention and control). The control group received general feedback after answering a questionnaire, while the intervention group received a 6-month plan of exercises and PNE created by a physical therapist with 10 years of experience. Our primary outcome was the scores of the Japanese version of the World Health Organization Health and Work Performance Questionnaire (WHO-HPQ) to investigate presenteeism; and our secondary outcomes were pain intensity, widespread pain index (WPI), and EuroQol 5-dimension (EQ5D-5L). RESULTS: In the intervention group, post intervention, we observed significant improvement in presenteeism, pain intensity, WPI, physical and psychological stress, and EQ5D-5L (P < .05). In the control group, we noted significant improvement only in the physical and psychological stress post intervention (P < .05). The results showed significant between-group differences in presenteeism post-intervention (P < .05). CONCLUSION: We demonstrated that a combination of PNE and exercise decreases presenteeism of healthcare workers. Our findings will help healthcare facilities carry out better employee management and ensure optimal productivity.

The Impact of Sedentary Behavior After Childbirth on Postpartum Lumbopelvic Pain Prolongation: A Follow-Up Cohort Study.

Background: A substantial number of women have postpartum lumbopelvic pain (LBPP). Additionally, many postpartum women stay for long inactivity. Therefore, we examined the impact of sedentary behavior on persistent postpartum LBPP and the difference in this impact due to parity. Materials and Methods: This cohort study followed up women who had reported LBPP at 4 months postpartum and divided them into the presence or absence of LBPP at 10 months postpartum. Sedentary time and physical activity were assessed at 4 months postpartum using the International Physical Activity Questionnaire short form. Univariate and multivariate logistic regression analysis was used to calculate persistent LBPP odds ratios (ORs) according to sedentary times, followed by stratification analysis by parity. The institutional review board approval was obtained. Results: A total of 182 women (32.1 ± 5.1 years old) were included for analysis and 112 (61.5%) participants had persistent LBPP at 10 months postpartum. Those with persistent LBPP at 10 months postpartum had increased sedentary time (5.0 [3.0-7.0] hours vs. 3.5 [2.0-6.0] hours, p = 0.05) at 4 months compared with those without LBPP. Even after adjusting for confounding factors, longer sedentary time at 4 months postpartum affected persistent LBPP at 10 months postpartum in primiparas (adjusted OR [95% confidence interval, CI] = 1.28 [1.05-1.55]), but longer sedentary time at 4 months postpartum did not affect persistent LBPP at 10 months postpartum in multiparas (adjusted OR [95% CI] = 0.96 [0.86-1.07]). Conclusion: Sedentary behavior after childbirth is associated with persistent postpartum LBPP in primiparas, but not multiparas. Reducing sedentary time might be beneficial to prevent persistent postpartum LBPP for primiparas.

Development and Psychometric Testing of the Japanese Version of the Fremantle Neck Awareness Questionnaire: A Cross-Sectional Study.

PURPOSE: Contemporary theories of pain suggest that how the body is perceived is central to the emergence of pain. The Fremantle Back Awareness Questionnaire (FreBAQ) was developed to assess body-perception specific to the back in people with chronic low back pain. However, there is no comprehensive measure to quantify self-perception of the painful area in Japanese people with neck pain. This study aimed to develop a Japanese version of a self-perception questionnaire specific to the neck and evaluate the validity and reliability of the scale using Rasch analysis. MATERIALS AND METHODS: The Fremantle Neck Awareness Questionnaire (FreNAQ-J) was developed by modifying the FreBAQ-J. One hundred people with chronic neck pain and fifty-six matched healthy controls completed the questionnaire. Rasch analysis was used to evaluate targeting, category order, unidimensionality, person fit, internal consistency, differential item functioning, and differential test functioning in the neck pain population. Validity was investigated by examining the relationship between the FreNAQ-J and clinical status. RESULTS: People with chronic neck pain endorsed FreNAQ-J items with greater frequency than healthy controls. FreNAQ-J did not reject the null hypothesis of fitting the Rasch model, had acceptable internal consistency and good test-retest reliability. Summed FreNAQ-J scores were significantly correlated with pain intensity, disability, pain-related catastrophizing and fear of movement. CONCLUSION: The individual items of the FreNAQ-J can be validly summed to provide a score of self-perception. The FreNAQ-J is the first scale developed for comprehensively evaluating disturbed body perception in Japanese patients with chronic neck pain.

Difference in the impact of central sensitization on pain-related symptoms between patients with chronic low back pain and knee osteoarthritis.

Purpose: The aims of the present study were to investigate whether the association between the Central Sensitization Inventory (CSI) score, pain-related symptoms, pain-related disability, and health-related quality of life differed by disease (chronic low back pain [CLBP] vs knee osteoarthritis [KOA]), and to determine optimal cutoff scores for the CSI reflecting disease-specific characteristics. Patients and methods: A total of 104 patients with CLBP and 50 patients with KOA were recruited. Central sensitization-related symptoms (CSI), EuroQol 5-dimension (EQ-5D), Brief Pain Inventory, widespread pain (Widespread Pain Index [WPI]), pressure pain threshold (PPT), and temporal summation (TS) were assessed and compared between the CLBP and KOA groups. Univariate correlation analysis was performed in each group. The receiver operating characteristic (ROC) curve analysis was performed to identify 1) presence/absence of central sensitization (CS), 2) presence/absence of central sensitivity syndromes (CSSs), and 3) pain intensity and pain interference in each group. Results: The CSI and WPI scores were significantly higher in the CLBP group than in the KOA group. EQ-5D and pain interference scores significantly correlated with the CSI score in both the CLBP and KOA groups. The WPI score, PPT, and TS did not correlate with the CSI score in either the CLBP or KOA group. The suggested cutoff scores were 28 in the CLBP group and 17 in the KOA group to identify presence or absence of CSSs, and 34 in the CLBP group and 18-19 in the KOA group to identify pain severity. Conclusion: The impact of CS on pain could differ between CLBP and KOA and that cutoff scores differ by each parameter we attempted to identify. Therefore, we should use the appropriate cutoff scores for the purposes and consider the difference in the impact of CS on pain by the patient group.

Comparison of central sensitization-related symptoms and health-related quality of life between breast cancer survivors with and without chronic pain and healthy controls.

BACKGROUND: In breast cancer survivors, multiple risk factors for health-related quality of life (HRQoL) and chronic pain, including cancer treatment-related factors, psychosocial factors, and central sensitization (CS), have been suggested; however, there has been no comparative study between breast cancer survivors with and without pain. This study aimed to compare the demographic characteristics, psychological factors, and CS-related symptoms between breast cancer survivors with pain, those without pain, and healthy controls, and to investigate the relationships of these factors with HRQoL. METHODS: We conducted a cross-sectional survey of 218 women, including patients who underwent breast cancer surgery and adjuvant therapy and healthy women. RESULTS: Patients were divided into the pain group (n = 42), without-pain group (n = 51), and healthy group (n = 47); thus, among breast cancer survivors, 45% reported chronic pain. The proportion of participants who received breast cancer treatments, such as axillary lymph node dissection and chemotherapy, was higher in the pain group than in the without-pain group (p < 0.05). The Central Sensitization Inventory (CSI) and psychosocial factors in the pain group were higher than those in the without-pain group and healthy group (p < 0.01). The CSI and PCS showed larger effect sizes than treatment-related factors. Moreover, HRQoL was significantly correlated with CSI, PCS, Patient Health Questionnaire-2, and Generalized Anxiety Disorder-2 scale (all, p < 0.01). On multiple linear regression analysis, CSI accounted for 43% of the variance in HRQoL. CONCLUSIONS: CS and pain catastrophizing may be more associated with the development and/or maintenance of persistent pain than treatment-related factors.

The central sensitization inventory predict pain-related disability for musculoskeletal disorders in the primary care setting.

BACKGROUND: Central sensitization (CS) is found in patients with musculoskeletal disorders and is related to clinical symptoms, including pain-related disability. The Central Sensitization Inventory (CSI) has been developed for patients who are at risk of symptoms related to CS, and CSI severity levels are suggested for clinical interpretation of the CSI score. However, the longitudinal relationship between CSI severity and pain-related disability is unclear in primary care. In this study, we investigated the association between CSI severity levels and the profiles of patients with musculoskeletal disorders as well as the longitudinal relationship between CSI severity levels and pain-related disability in primary care settings. METHODS: A total of 553 patients were assessed using CSI, EuroQol-5 dimension (EQ5D), and Brief Pain Inventory (BPI). Of the 553 patients, 150 patients were reassessed at the 3-month follow-up. Patients were grouped into three severity levels according to baseline CSI score: subclinical, mild, and moderate to higher level. RESULTS: As the CSI severity levels increased, the clinical symptoms tended to worsen on cross-sectional analysis (p < 0.05). Pain-related disability at the 3-month follow-up was significantly higher for patients with moderate to high baseline CSI severity levels than for patients with subclinical baseline CSI levels (p < 0.001). Furthermore, pain-related disability increased according to the CSI severity level, with a medium to large effect size. However, there were no differences in pain duration across the CSI severity levels. CONCLUSIONS: CSI has clinical utility as a prediction tool regardless of pain duration in patients with musculoskeletal disorders in primary care settings. SIGNIFICANCE: Higher CSI severity levels predicted higher pain-related disability for patients with musculoskeletal disorders in a primary care setting. CSI is a clinically useful prediction tool in patients with musculoskeletal disorders.