Factors associated with the orthopaedic surgeon's decision to recommend total joint replacement in hip and knee osteoarthritis: an international cross-sectional study of 1905 patients.

OBJECTIVE: To determine factors associated with orthopaedic surgeons' decision to recommend total joint replacement (TJR) in people with knee and hip osteoarthritis (OA). DESIGN: Cross-sectional study in eleven countries. For consecutive outpatients with definite hip or knee OA consulting an orthopaedic surgeon, the surgeon's indication of TJR was collected, as well as patients' characteristics including comorbidities and social situation, OA symptom duration, pain, stiffness and function (Western Ontario and McMaster Universities Osteoarthritis Index [WOMAC]), joint-specific quality of life, Osteoarthritis Research Society International (OARSI) joint space narrowing (JSN) radiographic grade (0-4), and surgeons' characteristics. Univariable and multivariable logistic regressions were performed to identify factors associated with the indication of TJR, adjusted by country. RESULTS: In total, 1905 patients were included: mean age was 66.5 (standard deviation [SD], 10.8) years, 1082 (58.0%) were women, mean OA symptom duration was 5.0 (SD 7.0) years. TJR was recommended in 561/1127 (49.8%) knee OA and 542/778 (69.7%) hip OA patients. In multivariable analysis on 516 patients with complete data, the variables associated with TJR indication were radiographic grade (Odds Ratio, OR for one grade increase, for knee and hip OA, respectively: 2.90, 95% confidence interval [1.69-4.97] and 3.30 [2.17-5.03]) and WOMAC total score (OR for 10 points increase: 1.65 [1.32-2.06] and 1.38 [1.15-1.66], respectively). After excluding radiographic grade from the analyses, on 1265 patients, greater WOMAC total score was the main predictor for knee and hip OA; older age was also significant for knee OA. CONCLUSION: Radiographic severity and patient-reported pain and function play a major role in surgeons' recommendation for TJR.

Neuropathic pain in end-stage hip and knee osteoarthritis: differential associations with patient-reported pain at rest and pain on activity.

OBJECTIVE: We investigated whether pain at rest and pain on activity were differentially associated with neuropathic pain scores in individuals with end-stage hip and knee OA. DESIGN: Study participants were 843 patients with hip or knee OA scheduled for total joint arthroplasty. In pre-surgery questionnaires, measures of socio-demographics, health status, medication use, neuropathic pain (painDETECT), pain at rest and pain on activity (WOMAC pain items), depression (HADS) and pain catastrophizing (PCS) were collected. Multivariable linear regression models were estimated for men and women separately to examine the association between neuropathic pain scores (outcome) and study measures, entered in blocks. RESULTS: Sample mean age was 65.1 years (SD: 9.6); 57.1% were women. Mean painDETECT scores were significantly higher (P ≤Ö¹ 0.001) for women (11.2 ± 6.6 out of 38) than men (9.3 ± 7.0), with 35.6% of women and 27.7% of men meeting cut-offs for possible or likely neuropathic pain. In the final regression model for women, the coefficients for both types of pain were statistically significant, although the coefficient for pain at rest was 1.6 times greater than that for pain on activity. For men, only pain at rest was significantly associated with neuropathic pain scores. CONCLUSIONS: Findings support that possible neuropathic pain is experienced by a notable proportion of patients with end-stage hip and knee OA and is more strongly associated with pain at rest than pain on activity, particularly in men. Clinical presentation of pain at rest may warrant more thorough evaluation for potential neuropathic pain and have implications for appropriate pain management.

Systemic inflammation and painful joint burden in osteoarthritis: a matter of sex?

OBJECTIVE: We investigated the association between serum levels of C-reactive protein (CRP) and the extent of multijoint pain among individuals with hip/knee osteoarthritis (OA) and determined whether the association differs by sex. DESIGN: Serum CRP and cartilage oligomeric matrix protein (COMP) were determined by enzyme-linked immunosorbent assay (ELISA) in 189 individuals (101 female, 88 male) scheduled for total hip/knee arthroplasty for OA. Patients indicated on a homunculus all painful joints; a summed count was derived. A series of negative binomial regression models was used to investigate the cross-sectional association between painful joint count (outcome) and serum CRP concentrations, adjusting for age, sex, body mass index (BMI), comorbidity count and COMP. An interaction between sex and these biomarkers was tested. RESULTS: Mean age: 66 among women, 65 among men. Women had higher mean joint count (3.7 vs 2.5, P < 0.01; 4+ joint count reported by 37% women, 25% men). Median CRP concentration was higher in women (15.4 mg/l vs 9.3, P = 0.07). From adjusted analyses, the effects of both ln(CRP) and ln(COMP) were modified by sex (P < 0.05). Increasing ln(CRP) was associated with greater painful joint count among women, but not men. CONCLUSIONS: There may be a dose-response association between painful joint burden in OA and systemic inflammation, and it appears the association is sex-specific, which may in part explain inconsistent findings in the literature. Our results underline the importance of showing sex-specific associations in OA, especially when studying the influence of inflammation.

Identification of synovial fluid microRNA signature in knee osteoarthritis: differentiating early- and late-stage knee osteoarthritis.

OBJECTIVES: This study aimed to identify circulating microRNA (miRNA) signatures in knee synovial fluid (SF) from early-stage and late-stage knee osteoarthritis (OA) patients. METHODS: miRNAs were screened by miRNA-PCR-arrays and validated by Real-time quantitative polymerase chain reaction (RT-qPCR) in SF from early-stage (Kellgren-Lawrence (KL): Grade: I/II) and late-stage OA patients (Grade: III/IV). OA cartilage or synovial explants were cultured to study the source/release of identified miRNAs. Computational-approach was utilized to predict gene/pathway targets. RESULTS: Our screening/validation analysis identified a panel of seven (out of 752) circulating miRNAs (23a-3p, 24-3p, 27a-3p, 27b-3p, 29c-3p, 34a-5p and 186-5p) that were significantly differentially expressed in late-stage vs early-stage OA-SF, irrespective of age, gender and Body Mass Index (BMI). miR-378a-5p was mostly detectable in majority of late-stage OA-SF. Cartilage explants stimulated with IL-1ß showed a significant reduction in miR-23a-3p, 27a-3p and 27b-3p expression with no significant changes in other validated miRNAs. However, IL-1ß-stimulated OA synovial explants exhibited significantly increased expression of miR-23a-3p, 24-3p, 27a-3p, 27b-3p, 29c-3p, 186-5p and 378a-5p, and release of only 23a-3p and 27b-3p in supernatants, suggesting that IL-1ß contributes to the release of 23a-3p and 27b-3p into the SF from synovium. Computational-analysis identified 2 genes (ROQUIN-1 [RC3H1] and quaking-gene [QKI]) that are targeted by six out of eight miRNAs; miR-27b-3p exhibited greatest association with RC3H1 and QKI genes. Indeed, synovial explants treated with miR-27b-3p-mimic show significant suppression of both RC3H1 and QKI genes. CONCLUSIONS: We provide first evidence of the differential expression of circulating miRNAs in early-stage vs late-stage knee OA-SF. Further, we provide source, release and genes/pathways regulated by identified miRNAs.

The importance of perceived helplessness and emotional health in understanding the relationship among pain, function, and satisfaction following revision knee replacement surgery.

OBJECTIVE: Little is known about the relationships among pain, function, psychological variables like perceived helplessness and emotional health, and patient satisfaction in people with revision knee replacement surgery. We hypothesized that pain and function would have a direct association with satisfaction as well as an indirect association through patient perceptions of helplessness and emotional health. DESIGN: This longitudinal study included 145 participants undergoing revision knee replacement surgery. Demographic data and expectation of benefit from surgery were recorded prior to surgery. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), the Arthritis Helplessness Scale (AHS) and the Mental Component Scale (MCS) of the SF-36 (emotional health) were collected prior to and 2 years post-surgery. Satisfaction was recorded 2 years post-surgery. Regression analyses were conducted to test for mediation effects of helplessness and MCS. RESULTS: Participants were on average 69 years old and 54% were women. Participants were satisfied with the results of the surgery (mean ± standard deviation (SD) = 70.42 ± 31.46). Less pain and functional disability were associated with increased patient satisfaction and, the effect of pain or function was also mediated through helplessness whereby more pain and disability were associated with perceptions of helplessness and helplessness was associated with lower satisfaction. MCS did not mediate the relationship of pain and function with satisfaction. CONCLUSION: Helplessness plays an important role in understanding patient satisfaction. Interventions aimed at improving patient outcome should target not only pain and function but also should address strategies to support people in managing following knee revision surgery to maximize satisfaction with outcome.

Predicting return to work following treatment of chronic pain disorder.

BACKGROUND: The care of injured workers with chronic pain remains an important public health issue given its increasing prevalence. The consequences often include loss of self-esteem and stress in family relationships. AIMS: To report our interdisciplinary approach to the care of chronic pain disorder (CPD) and describe the predictors associated with a successful return to work (RTW). METHODS: Relevant covariates, including demographic data, time from injury, and functional scores were recorded for clients injured at work in Ontario, Canada. Our primary outcome, RTW, was assessed at 3 months post-discharge. Descriptive statistics and logistic regression were used to identify those factors predicting a successful RTW. RESULTS: Of the injured workers who participated in the interdisciplinary CPD treatment programme, 1002 clients met our inclusion criteria and were included in the study. Fifty-five per cent were male with a mean age of 46 years. Median time from injury to treatment was 720 days. At 3 months post-treatment, 136 (14%) of the participants were working. Multivariable logistic regression revealed that earlier time since injury (OR = 0.71, 95% CI 0.55-0.92) and presence of an RTW coordinator (RTWC) (OR = 3.42, 95% CI 2.08-5.63) were significant predictors of successful RTW. There was also a significant interaction between RTWC involvement and time since injury. The latter did not appear to influence the likelihood of RTW when an RTWC was present. CONCLUSIONS: Workers compensation boards should refer injured workers with CPD to treatment programmes as early as possible to achieve a successful RTW. Additionally, RTWCs play an important role in improving work outcomes.

Multiple joint involvement in total knee replacement for osteoarthritis: Effects on patient-reported outcomes.

OBJECTIVE: To determine whether symptomatic (painful/problematic) joints pre-total knee replacement (TKR) surgery influence 1) pre- and 12-month post-TKR patient-reported outcomes (pain, physical function, and mood [fatigue, anxiety, and depression]) and 2) postsurgical pain and function mediated through mood. METHODS: A total of 494 participants completed the patient-reported outcome measures pre- and 12-months post-TKR. Symptomatic (painful/problematic) joints affected by arthritis were indicated on a homunculus presurgery. Covariate data included age, sex, educational attainment, body mass index, and comorbidity. Pre- and postsurgical outcome scores were regressed on symptomatic joint sites and covariates using linear regression analyses; postsurgical scores additionally were regressed on presurgery scores. Path analyses examined whether the effects of symptomatic joint sites on postsurgical pain and function were mediated through mood. RESULTS: The age range was 35-88 years (mean 65 years) and 65% were women. Forty-six percent reported ≥4 symptomatic joints (other than the surgical knee). Pre- and postsurgery, worse outcome scores were observed with increasing joint count. Adjusted for covariates, individuals reporting symptomatic ankles/feet/toes, neck, and spine/lower back had worse presurgery fatigue and anxiety. Adjusted for covariates and presurgery status, worse fatigue for the neck and spine/lower back and worse depression, pain, and function for the ankles/feet/toes and neck were observed postsurgery. The influence of symptomatic ankles/feet/toes on postsurgical pain and function was in part direct and partially mediated through depression. Full mediation was found for the neck through fatigue, anxiety, and depression, and for the spine/lower back through fatigue. CONCLUSION: Findings suggest that a comprehensive approach to osteoarthritis management/care is warranted, and identify important associations between symptomatic joints and mood that negatively impact post-TKR pain and physical function.

The trajectory of recovery and the inter-relationships of symptoms, activity and participation in the first year following total hip and knee replacement.

OBJECTIVE: Primary total hip (THR) and knee (TKR) replacement outcomes typically include pain and function with a single time of follow-up post-surgery. This research evaluated the trajectory of recovery and inter-relationships within and across time of physical impairments (PI) (e.g., symptoms), activity limitations (AL), and social participation restrictions (PR) in the year following THR and TKR for osteoarthritis. DESIGN: Participants (hip: n=437; knee: 494) completed measures pre-surgery and at 2 weeks, 1, 3, 6 and 12 months post-surgery. These included PI (Hip Disability and Osteoarthritis Outcome Score (HOOS)/Knee Injury and Osteoarthritis Outcome Score (KOOS) symptoms and Chronic Pain Grade); AL (HOOS/KOOS activities of daily living and sports/leisure activities); and, PR (Late Life Disability and the Calderdale community mobility). Repeated measures analysis of variance (RANOVA) was used to evaluate the trajectory of recovery of outcomes and the inter-relationships of PI, AL and PR were evaluated using path analysis. All analyses were adjusted for age, sex, obesity, THR/TKR, low back pain and mood. RESULTS: THR: age 31-86 years with 55% female; TKR: age 35-88 years with 65% female. Significant improvements in outcomes were observed over time. However, improvements were lagged over time with earlier improvements in PI and AL and later improvements in PR. Within and across time, PI was associated with AL and AL was associated with PR. The magnitude of these inter-relationships varied over time. CONCLUSION: Given the lagged inter-relationship of PI, AL and PR, the provision and timing of interventions targeting all constructs are critical to maximizing outcome. Current care pathways focusing on short-term follow-up with limited attention to social and community participation should be re-evaluated.

The role of pain and functional impairment in the decision to recommend total joint replacement in hip and knee osteoarthritis: an international cross-sectional study of 1909 patients. Report of the OARSI-OMERACT Task Force on total joint replacement.

OBJECTIVE: To assess the pain and functional disability levels corresponding to an indication for total joint replacement (TJR) in hip and knee osteoarthritis (OA). DESIGN: International cross-sectional study in 10 countries. PATIENTS: Consecutive outpatients with definite hip or knee OA attending an orthopaedic outpatient clinic. Gold standard measure for recommendation for TJR: Surgeon's decision that TJR is justified. OUTCOME MEASURES: Pain (ICOAP: intermittent and constant osteoarthritis pain, 0-100) and functional impairment (HOOS-PS/KOOS-PS: Hip/Knee injury and Osteoarthritis Outcome Score Physical function Short-form, 0-100). ANALYSES: Comparison of patients with vs without surgeons' indication for TJR. Receiver Operating Characteristic (ROC) curve analyses and logistic regression were applied to determine cut points of pain and disability defining recommendation for TJR. RESULTS: In all, 1909 patients were included (1130 knee/779 hip OA). Mean age was 66.4 [standard deviation (SD) 10.9] years, 58.1% were women; 628/1130 (55.6%) knee OA and 574/779 (73.7%) hip OA patients were recommended for TJR. Although patients recommended for TJR (yes vs no) had worse symptom levels [pain, 55.5 (95% confidence interval 54.2, 56.8) vs. 44.9 (43.2, 46.6), and functional impairment, 59.8 (58.7, 60.9) vs. 50.9 (49.3, 52.4), respectively, both P<0.0001], there was substantial overlap in symptom levels between groups, even when adjusting for radiographic joint status. Thus, it was not possible to determine cut points for pain and function defining 'requirement for TJR'. CONCLUSION: Although symptom levels were higher in patients recommended for TJR, pain and functional disability alone did not discriminate between those who were and were not considered to need TJR by the orthopaedic surgeon.

Survival and clinical function of cemented and uncemented prostheses in total knee replacement: a meta-analysis.

Using meta-analysis we compared the survival and clinical outcomes of cemented and uncemented techniques in primary total knee replacement. We reviewed randomised controlled trials and observational studies comparing cemented and uncemented fixation. Our primary outcome was survival of the implant free of aseptic loosening. Our secondary outcome was joint function as measured by the Knee Society score. We identified 15 studies that met our final eligibility criteria. The combined odds ratio for failure of the implant due to aseptic loosening for the uncemented group was 4.2 (95% confidence interval (CI) 2.7 to 6.5) (p < 0.0001). Subgroup analysis of data only from randomised controlled trials showed no differences between the groups for odds of aseptic loosening (odds ratio 1.9, 95% CI 0.55 to 6.40, p = 0.314). The weighted mean difference for the Knee Society score was 0.005 (95% CI -0.26 to 0.26) (p = 0.972). There was improved survival of the cemented compared to uncemented implants, with no statistically significant difference in the mean Knee Society score between groups for all pooled data.

Psychosocial and geriatric correlates of functional status after total hip replacement.

OBJECTIVE: To determine whether psychosocial factors, chronic diseases, and common geriatric problems are associated with poor physical function 3 years after primary total hip replacement (THR). METHODS: We studied a sample of Medicare recipients in Ohio, Pennsylvania, and Colorado (n = 922) who underwent primary THR in 1995 (mean +/- SD age 73.1 +/- 5.6 years, 32% men). Participants completed a questionnaire regarding lifestyle factors, medical history, and quality of life approximately 3 years after the surgery. Physical function was measured using the function subscale of the Western Ontario and McMaster Universities Osteoarthritis Index. We assessed the relationship between functional outcome 3 years postsurgery and 4 predictor domains: pain or complications in the operated hip, other musculoskeletal comorbidity, medical factors (obesity, chronic medical comorbidity, rheumatoid arthritis, and such common geriatric problems as falls, poor balance, or incontinence), and psychosocial factors (mental health, regular alcohol consumption, smoking, provider role, living alone, and education). RESULTS: Ten percent of subjects had poor functional status. In a logistic regression model controlling for sex and age, the following factors were associated with an increased risk for poor functional status (in order of importance): pain in the back or lower extremity, severe pain in the operated hip, poor mental health, more than 1 common geriatric problem, obesity, and less than college education. CONCLUSION: Pain in the operated hip was strongly associated with poor functional status 3 years after THR. However, other factors associated with poor functional status were not related to the hip. Our results suggest that a comprehensive assessment of functional status in elderly THR patients should include assessment of common geriatric problems, mental health status, and weight.

Association between hospital and surgeon procedure volume and outcomes of total hip replacement in the United States medicare population.

BACKGROUND: The mortality and complication rates of many surgical procedures are inversely related to hospital procedure volume. The objective of this study was to determine whether the volumes of primary and revision total hip replacements performed at hospitals and by surgeons are associated with rates of mortality and complications. METHODS: We analyzed claims data of Medicare recipients who underwent elective primary total hip replacement (58,521 procedures) or revision total hip replacement (12,956 procedures) between July 1995 and June 1996. We assessed the relationship between surgeon and hospital procedure volume and mortality, dislocation, deep infection, and pulmonary embolus in the first ninety days postoperatively. Analyses were adjusted for age, gender, arthritis diagnosis, comorbid conditions, and income. Analyses of hospital volume were adjusted for surgeon volume, and analyses of surgeon volume were adjusted for hospital volume. RESULTS: Twelve percent of all primary total hip replacements and 49% of all revisions were performed in centers in which ten or fewer of these procedures were carried out in the Medicare population annually. In addition, 52% of the primary total hip replacements and 77% of the revisions were performed by surgeons who carried out ten or fewer of these procedures annually. Patients treated with primary total hip replacement in hospitals in which more than 100 of the procedures were performed per year had a lower risk of death than those treated with primary replacement in hospitals in which ten or fewer procedures were performed per year (mortality rate, 0.7% compared with 1.3%; adjusted odds ratio, 0.58; 95% confidence interval, 0.38, 0.89). Patients treated with primary total hip replacement by surgeons who performed more than fifty of those procedures in Medicare beneficiaries per year had a lower risk of dislocation than those who were treated by surgeons who performed five or fewer of the procedures per year (dislocation rate, 1.5% compared with 4.2%; adjusted odds ratio, 0.49; 95% confidence interval, 0.34, 0.69). Patients who had revision total hip replacement done by surgeons who performed more than ten such procedures per year had a lower rate of mortality than patients who were treated by surgeons who performed three or fewer of the procedures per year (mortality rate, 1.5% compared with 3.1%; adjusted odds ratio, 0.65; 95% confidence interval, 0.44, 0.96). CONCLUSIONS: Patients treated at hospitals and by surgeons with higher annual caseloads of primary and revision total hip replacement had lower rates of mortality and of selected complications. These analyses of Medicare claims are limited by a lack of key clinical information such as operative details and preoperative functional status.

The Harris hip score: comparison of patient self-report with surgeon assessment.

Outcome evaluations are of primary concern in contemporary medical practice. Questionnaires are being used increasingly to provide input data for such outcomes evaluation. This study comprised 50 primary total hip arthroplasties in 36 patients who had undergone the procedure at least 12 months before enrollment. Each patient completed a self-report Harris Hip Score (HHS) 30 days before a formal evaluation by an independent orthopaedic surgeon that included a HHS. Comparison was made between the completed responses to the individual items on the self-report HHS and surgeon-assessed HHS. Concordance of item response and kappa statistic were calculated. Overall the self-report and surgeon-assessed HHS showed excellent concordance. The results of this study support the use of the HHS as a self-report instrument.

Determinants and outcomes of inpatient versus home based rehabilitation following elective hip and knee replacement.

OBJECTIVE: There are large variations in practice patterns and costs of rehabilitation following total joint replacement (TJR). We evaluated the determinants of rehabilitation setting (home based vs inpatient) after TJR, and its influence on early functional outcomes. METHODS: We studied a retrospective cohort of 146 primary total hip and knee replacements. Ninety-six patients completed a mailed survey consisting of the Western Ontario and McMaster University Osteoarthritis Index (WOMAC), the Medical Outcomes Survey Short Form-36 (SF-36), and a satisfaction questionnaire. RESULTS: The mean age of the cohort was 66 years, 70% were women, and osteoarthritis was the primary diagnosis in 79%. Thirty-nine percent received home based rehabilitation. Determinants of home based rehabilitation included preference for home based rehabilitation, male sex, and knowledge regarding TJR. At a mean followup of 8 months post TJR, there were no significant differences between the inpatient and home based rehabilitation groups with respect to the WOMAC, SF-36, and satisfaction scores. CONCLUSION. These results support continued use of home based rehabilitation.

Functional health status of adults with achondroplasia.

Little is known regarding the functional health status of individuals with achondroplasia. This cross-sectional survey of adults with achondroplasia was undertaken to assess the functional health status of this population and its determinants. The study sample consisted of members of the Little People of America (LPA) who completed a mailed questionnaire consisting of a demographics component, a general and disease-specific comorbidities component, and the Short Form 36 (SF-36) health status questionnaire. Univariate analyses and multivariate linear regression models were used for data analysis. Four hundred thirty-seven individuals with a mean age of 38 years completed the survey. The age- and gender-adjusted Mental Component Summary (MCS) scores did not significantly differ from those of the general population. In contrast, the age- and gender-adjusted Physical Component Summary (PCS) scores were significantly lower than the general population starting in the fourth decade of life. Musculoskeletal diseases were most prevalent and had the greatest impact on the PCS scores. Two-thirds of this cohort had undergone at least one operation. Only musculoskeletal procedures were significantly associated with PCS and MCS scores. The functional health status of adults with achondroplasia, as measured by the SF-36, is not drastically reduced in comparison with that of the general U.S. population.