Are outcomes after total knee arthroplasty worsening over time? A time-trends study of activity limitation and pain outcomes

Global mapping of institutional and hospital-based (Level II-IV) arthroplasty registries: a scoping review

PURPOSE

Four joint arthroplasty registries (JARs) levels exist based on the recorded data type. Level I JARs are national registries that record primary data. Hospital or institutional JARs (Level II-IV) document further data (patient-reported outcomes, demographic, radiographic). A worldwide list of Level II-IV JARs must be created to effectively assess and categorize these data.

METHODS

Our study is a systematic scoping review that followed the PRISMA guidelines and included 648 studies. Based on their publications, the study aimed to map the existing Level II-IV JARs worldwide. The secondary aim was to record their lifetime, publications' number and frequency and recognise differences with national JARs.

RESULTS

One hundred five Level II-IV JARs were identified. Forty-eight hospital-based, 45 institutional, and 12 regional JARs. Fifty JARs were found in America, 39 in Europe, nine in Asia, six in Oceania and one in Africa. They have published 485 cohorts, 91 case-series, 49 case-control, nine cross-sectional studies, eight registry protocols and six randomized trials. Most cohort studies were retrospective. Twenty-three per cent of papers studied patient-reported outcomes, 21.45% surgical complications, 13.73% postoperative clinical and 5.25% radiographic outcomes, and 11.88% were survival analyses. Forty-four JARs have published only one paper. Level I JARs primarily publish implant revision risk annual reports, while Level IV JARs collect comprehensive data to conduct retrospective cohort studies.

CONCLUSIONS

This is the first study mapping all Level II-IV JARs worldwide. Most JARs are found in Europe and America, reporting on retrospective cohorts, but only a few report on studies systematically.

Functional Outcome Change Over 10 Years After Primary Total Knee Arthroplasty. A Prospective Longitudinal Cohort Study

BACKGROUND

To assess any clinically important difference in functional outcome over 10 years after primary total knee arthroplasty (TKA).

METHODS

A prospective registry-based observational cohort study including 309 patients older than 60 years who underwent primary TKA. Patients were assessed at 1, 3, 5, 7 and 10 postoperative years with the Knee Society scores (KSS) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). Clinically important improvement was defined according to the minimal clinically important difference (MCID). Patients were also categorized as type A (unilateral knee osteoarthritis), type B (bilateral knee osteoarthritis) or type C (various sites of osteoarthritis).

RESULTS

The mean age at the TKA surgery was 69.2 (SD 7.3) years, 197 (63.7%) were women.Maximum postoperative improvements in functional scores occurred at 3 postoperative years, remained relatively stable up to 5-year. There were significant decreases in all KSS and WOMAC scores at 7-year follow-up (P = .001), remained stable up to 10-year. At 10-year, functional scores were significantly higher than preoperatively (P = .001). Differences between maximum scores at 3-year and those at 10-year were significantly lesser than MCID in all scores (P = .001). In multivariate analysis, type-C patient at TKA surgery was the only significant predictor of unsuccessful KSS score and dissatisfaction at 10-year follow-up.

CONCLUSION

Primary TKA provides clinically important improvements in functional and quality of life outcomes over 10-year follow-up compared to preoperatively. Although there were statistically significant declines in KSS and WOMAC scores from 3 to 10 years, the differences were lesser than the MCID.

Demographic, Comorbidity, and Episode-of-Care Differences in Primary Total Knee Arthroplasty

BACKGROUND

Understanding time trends in age, demographic characteristics, and comorbidities is especially critical to highlight the effects on clinical practice change, outcomes, and the value of total knee arthroplasty (TKA). Therefore, the purpose of this study was to identify trends in the demographic characteristics, comorbidities, and episode-of-care outcomes for patients who underwent TKA from 2008 to 2018.

METHODS

The National Surgical Quality Improvement Program (NSQIP) was queried to identify patient demographic characteristics, comorbidities, and episode-of-care outcomes in patients who underwent primary TKA from 2008 to 2018 (n = 350,879). Trends for continuous variables were analyzed using analysis of variance, and categorical variables were analyzed using chi-square tests.

RESULTS

From 2008 to 2018, there was no clinically important difference in age, body mass index (BMI), and percentage of patients with BMI of >40 kg/m2 and no clinically important difference in chronic obstructive pulmonary disease (3.5% in 2008 and 3.2% in 2018), congestive heart failure within 30 days (0.3% in both 2008 and 2018), and acute renal failure (0.1% in 2008 and <0.1% in 2018) among patients undergoing TKA. However, modifiable comorbidities, including smoking status (9.5% in 2008 and 7.7% in 2018; p < 0.001), hypertension (71.0% in 2008 and 63.7% in 2018; p < 0.001), and anemia (16.2% in 2008 and 9.7% in 2018; p < 0.001), functional status, and overall morbidity and mortality probability have improved, with no clinically important difference in the percentage of diabetes (19.0% in 2008 and 18.1% in 2018). The hospital length of stay (mean [and standard deviation], 3.8 ± 2.2 days in 2008 and 2.1 ± 2.0 days in 2018; p < 0.001) and 30-day readmission (4.6% in 2011 and 3.0% in 2018; p < 0.001) decreased, with a significant increase in home discharge (65.6% in 2011 and 87.8% in 2018; p < 0.001).

CONCLUSIONS

The overall patient health status improved from 2008 to 2018, with improvement in the modifiable comorbidities of smoking status, malnutrition, hypertension, and anemia; the functional status; and the overall morbidity and mortality probability, with no clinically relevant change in patient age; patient BMI; percentage of patients with BMI of >40 kg/m2; or patients with diabetes mellitus, chronic obstructive pulmonary disease, congestive heart failure within 30 days, or acute renal failure. Our findings may be a reflection of a global shift toward value-based care focusing on patient optimization prior to arthroplasty, quality of care, and improved outcomes. The results of our study highlight the potential increase in TKA procedural value, which is paramount for health-care policy changes in today's incentivized, value-based, health-care environment.

Health related quality of life in patients having total knee replacement and associations with symptoms, recovery, and patient education: A six month follow up study

AIM

To describe the symptoms, recovery, patient education, and health related quality of life (HRQOL) of patients having total knee replacements at three time points and to detect experiences and situations that predict HRQOL six weeks and six months post-surgery.

METHOD

A prospective exploratory two-site study assessing 123 patients, while in hospital (T1), at six weeks (T2), and at six months (T3) post-discharge. HRQOL was measured using the SF-36v2 and symptoms were measured with the Hospital and Anxiety Scale. Two questions considered pain and two considered movement and tiredness while two questions addressed recovery and patient education. Linear regression models were used to calculate predictors of mental and physical HRQOL at T2 and T3.

RESULTS

HRQOL improved from T1 to T3. The main predictors of higher physical scores at T2 were; being older, fewer symptoms of depression and little distress related to movement. At T3 the main predictors were; having resumed work, finding patient education very useful, experiencing no pain in the last 24 h and fewer symptoms of depression. The main predictors of higher mental scores at T2 were fewer symptoms of anxiety and depression and little distress related to movement while at T3 these were fewer symptoms of anxiety and depression and experiencing no pain last 24 h.

CONCLUSION

Apart from pain, function and resumption of activities, the symptoms of anxiety and depression influence HRQOL. These symptoms should be assessed during the hospital stay.

Literature review of the causes of pain following total knee replacement surgery: prosthesis, inflammation and arthrofibrosis

Adverse knee pain occurs in 10–34% of all total knee replacements (TKR), and 20% of TKR patients experience more pain post-operatively than pre-operatively. Knee pain is amongst the top five reasons for knee replacement revision in the United Kingdom. The number of TKRs is predicted to continue increasing due to the ageing population.

A narrative literature review was performed on the different causes of pain following TKR. A database search on Scopus, PubMed, and Google Scholar was conducted to look for articles related to TKR, pain, and cause. Articles were selected based on relevance, publication date, quality of research and validation. Relevant sections were added to the review.

One hundred and fourteen articles were identified and potential causes of TKR pain included: arthrofibrosis, aseptic loosening, avascular necrosis, central sensitization, component malpositioning, infection, instability, nerve damage, overstuffing, patellar maltracking, polyethylene wear, psychological factors and unresurfaced patella.

It is important to tailor our approach to address the individual causes of pain. Certain controllable risk factors can be managed pre-operatively to minimize post-operative pain. Risk factors help to predict adverse pain outcomes and identify specific causes.

There are multiple causes of pain following TKR. Some factors will require further extensive studies, and as pain is a commonly attributed reason for TKR revision, its underlying aetiologies should be explored. Understanding these factors helps to develop effective methods for diagnosis, prevention and management of TKR pain, which help to improve patient outcomes.

Cite this article: EFORT Open Rev 2020;5:534-543. DOI: 10.1302/2058-5241.5.200031

Differences in pain measurement between nurses and physicians in a teaching hospital

Introduction: In clinical practice, the administration of opioid analgesics depends on pain severity records from nurses because they are responsible for determining the severity of the patient's complaints; however, discrepancies regarding pain measurement are often observed between physicians and graduated nurses, which can lead to an inadequate use of analgesics.Objective: To carry out a comparison of pain severity measurements made by staff physicians and nurses in a teaching hospital during the first 24 hours of hospital stay of patients with movement-related pain.Methods: Retrospective, cross-sectional study. Data were obtained from the pharmacy database and medical records (opioids prescribed for 1 month, pain intensity, and medication management). The medical records of 634 in patients who were prescribed at least 1 dose of an opioid analgesic were reviewed.Results: The average pain score provided by physicians (5.4/10; SEM=0.17) was significantly higher than the average pain score reported by nurses (3.5/10; SEM=0.15) (p<0.05). The intra-class correlation coefficient was 0.371 (95%CI: 0.138-0.563), indicating poor agreement between measurements.Conclusion: A poor agreement between pain measurements made by physicians and nurses during the first 24 hours of hospital stay was found. Bearing in mind that pain measurement is essential for achieving an appropriate treatment, the jointly provision of pain management education programs to doctors and nurses should be considered, so that they assess pain severity similarly, thus improving the management of inpatients and their quality of life.

Body-Self Unity With a New Hip or Knee: Understanding Total Joint Replacement Within an Embodiment Framework

Medical research increasingly makes use of embodiment concepts to understand how illness disrupts unity of body and self. However, few have applied embodiment concepts in total joint replacement (TJR), an effective treatment for end‐stage arthritis. In considering why a troubling proportion of TJR recipients have continued pain and functional limitation, we ask: what role might be played by the embodied experience of living with an implant? Relevant theoretical models and prior research on embodiment in musculoskeletal health and transplantation are reviewed. Our findings suggest a research agenda with implications for addressing suboptimal outcomes in TJR.

The prognostic value of pain catastrophizing in health-related quality of life judgments after Total knee arthroplasty

Background

Total knee arthroplasty (TKA) is a highly effective procedure that yields reductions in pain and disability associated with end stage osteoarthritis (OA) of the knee. Quality of life instruments are frequently used to gauge the outcomes of total knee arthroplasty (TKA). However, research suggests that post-TKA reductions in symptom severity may not be the sole predictors of quality of life post-TKA. The primary objective of the present study was to examine the prognostic value of catastrophic thinking in health-related quality of life (HRQoL) judgments in patients with severe OA after TKA.

Methods

In this study we used a prospective cohort design to examine the value of pain catastrophizing in predicting HRQoL 1 year after TKA. Participants with advanced OA of the knee who were scheduled for TKA were recruited at one of three hospitals in Canada. The study sample consisted of 116 individuals (71 women, 45 men) who completed study questionnaires at their pre-surgical evaluation and 1 year after surgery. Hierarchical regression analysis was used to assess the unique contribution of pre-surgical pain catastrophizing to the prediction of post-surgical HRQoL judgments.

Results

The results of the hierarchical regression equation revealed that the overall model was significant, F (9,106) = 8.3, p < 001, and accounted for 36.4% of the variance in the prediction of post-surgical physical component score of HRQoL. Pain catastrophizing was entered in the last step of the equation and contributed significant unique variance (β = −.35, p < .001) to the prediction of post-surgical physical component score of HRQoL above and beyond the variance accounted for by demographic variables, co-morbid health conditions, baseline HRQoL, and post-surgical reductions in pain, joint stiffness and physical disability.

Conclusions

The current findings highlight the importance of pre-surgical catastrophic cognitions in influencing HRQoL judgments after TKA. The findings suggest that psychosocial interventions designed to reduce pain catastrophizing before TKA might contribute to better quality of life outcomes following surgery.

Quality of life after total knee arthroplasty

Total knee arthroplasty (TKA) results in a high degree of patient satisfaction, as it provides patients with considerable medium- and long-term benefits in terms of quality of life, pain relief and function. Nevertheless, the literature reports that up to 30% of patients are dissatisfied. This dissatisfaction is directly related to the patients' quality of life, which they deem insufficient. Their quality of life depends on many physical, behavioural, social and psychological factors that are not taken into account by functional outcome scores. After describing the principles of quality of life evaluation after TKA, we will assess the effects of patient-related factors, the surgical technique and postoperative program through an exhaustive review of the literature. Patient expectations after TKA will then be outlined, particularly return to work and return to sports.

Comparative Effectiveness of Intra-Articular Hyaluronic Acid and Corticosteroid Injections on the Time to Surgical Knee Procedures

BACKGROUND

Use of intra-articular hyaluronic acid (HA) injections to manage knee osteoarthritis (OA) remains controversial because of weak and conflicting evidence. The objective was to evaluate the effectiveness of intra-articular HA injections for knee OA management.

METHODS

A nested cohort of persons with knee OA seeing a specialist was created using a 10% random sample of LifeLink Plus claims (2010-2015) to compare the risk of composite (any) knee surgical interventions, total (TKA)/unicompartmental knee arthroplasty (UKA) and TKA only among HA users and 2 comparison groups: corticosteroid (CS) users and HA/CS nonusers. A high-dimensional propensity score (hdPS) was used to match HA users with CS users and with HA/CS nonusers on background covariates. The risk of surgical interventions among HA users relative to the comparison groups was assessed using Cox proportional hazard models.

RESULTS

Among 13,849 patients, 797 were HA users, 5327 were CS users, and 7725 were HA/CS nonusers. After hdPS matching, the risk of composite surgical interventions did not differ between HA users and HA/CS nonusers (hazard ratio [HR], 0.88; 95% confidence interval [CI], 0.67-1.16) and CS users (HR, 0.89; 95% CI, 0.65-1.12). Seven of the 8 sensitivity analyses demonstrated no significant benefit among HA users compared to CS users and HA/CS nonusers. A sensitivity analysis that restricted the study cohort to those who ultimately have knee surgery showed a lower risk of surgery of HA (HR, 0.87; 95% CI, 0.79-0.95).

CONCLUSION

There were no significant differences in the risk of surgical interventions among HA users compared to HA/CS nonusers and CS users after accounting for residual confounding using an hdPS.

Surgeon's Preference in Total Knee Replacement: A Quantitative Examination of Attributes, Reasons for Alteration, and Barriers to Change

BACKGROUND

The reasons why surgeons prefer a particular total knee replacement (TKR) to other viable options with lower cost or lower revision risk remain uncertain. This study examined the concept of surgeon's preference in TKR; including the self-assigned utility of their preferred prosthesis, reasons to alter usual preference and barriers to permanently changing preference.

METHODS

Using a multinational electronic survey, 347 TKR performing orthopedic surgeons were studied using anonymous mandatory responses, mutually exclusive closed options, multiple responses blocking, automatic stem randomization, Likert scale weighting, and an absence of neutral options.

RESULTS

The highest rated of the 17 attributes were "reproducibility of outcome," "best functional outcome," and "better kinematics." The lowest rated were a "key-opinion leader or mentor uses it" and "new or innovative." "Lowest revision risk" ranked 10th, with 19.9% of surgeons stating it did not influence their preference. Cost did not influence 52.1% of surgeons and 33.7% agreed that their institution or system limited their preference. Surgeon's demographics and preferred prosthesis or technique altered some attribute ratings including surgical volume, country of practice, type of preferred implant; however, revision risk rating was not altered by any factor. Cost considerations altered rating of barriers to technique change.

CONCLUSION

Understanding why surgeons prefer certain TKR prostheses or techniques to other viable alternatives is vital to reduce unwarranted variation. This study suggests that the self-assigned reasons driving surgeon's preferences, reasons for preference alteration, and barriers to change are multifactorial, diverse, and complex, with revision risk not being the highest rated attribute.

Comparison of Low-, Moderate-, and High-Molecular-Weight Hyaluronic Acid Injections in Delaying Time to Knee Surgery

BACKGROUND

We compared the effectiveness of low-molecular-weight (MW) hyaluronic acid (HA) injections (LMWHA), moderate-MW HA injections (MMWHA), and high-MW HA injections (HMWHA) for prevention or delay of knee surgery in patients with knee osteoarthritis.

METHODS

An observational cohort study using LifeLink Plus claims (2006-2015) was used. The primary outcome measure of the study included all surgical interventions of the knee. The secondary outcome measures were the following: (1) unicompartmental knee arthroplasty or total knee arthroplasty and (2) total knee arthroplasty only. A high-dimensional propensity score (hdPS) using 1:1 matching was used to adjust for confounding. The likelihood of each outcome was assessed using Cox proportional hazard models.

RESULTS

A cohort of 30,417 incident HA users with knee osteoarthritis met our inclusion-exclusion criteria. There was no difference in the likelihood of composite surgical events between LMWHA users (hazard ratio, 0.939; 95% confidence interval, 0.870-1.013) and MMWHA users (hazard ratio, 1.032; 95% confidence interval, 0.952-1.119) when compared with HMWHA users in a matched hdPS analysis. However, a significantly lower likelihood for all outcome measures was demonstrated in LMWHA and MMWHA users compared with HMWHA users when hdPS was not used.

CONCLUSION

There was no significant difference in the likelihood of surgical interventions between LMWHA, MMWHA, and HMWHA users after accounting for empirically derived confounders.

Patient-reported health outcomes after total hip and knee surgery in a Dutch University Hospital Setting: results of twenty years clinical registry

Background

Patient-Reported Outcome (PRO) measurement is a method for measuring perceptions of patients on their health and quality of life. The aim of this paper is to present the results of PRO measurements in total hip and knee replacement as routinely collected during 20 years of surgery in a university hospital setting.

Methods

Data of consecutive patients between 1993 and 2014 were collected. Health outcomes were measured pre-surgery and at 3, 6, and 12 months post-surgery. Outcomes for hip replacement were measured with the Harris Hip Score (HHS) and Oxford Hip Score (OHS). Outcomes for knee replacement were measured with the Western Ontario and McMaster Universities Arthritis Index (WOMAC) and the Knee Society Score (KSS). A Visual Analog Scale (VAS) for pain was used. Absolute and relative Minimal Clinically Important Differences (MCID) were estimated. Generalized estimating equation analysis was used for estimating mean outcomes. Trends over time were analyzed.

Results

The database contained 2,089 patients with hip replacement, and 704 patients with knee replacement. Mean HHS and OHS scores in primary hip replacement at 12 months post-surgery were 86.7 (SD: 14.5) and 41.1 (SD: 7.5) respectively. Improvements on the HHS based on absolute MCID was lower for revisions compared to primary hip replacements, with 72.4% and 87.0% respectively. Mean WOMAC and KSS scores in knee replacement at 12 months post-surgery were 21.5 (SD: 18.2) and 67.0 (SD: 26.4) respectively. Improvements based on absolute MCID were lowest for the KSS (62.6%) and highest for VAS pain (85.6%). Trend analysis showed a difference in 1 out of 24 comparisons in hip replacement and in 2 out of 9 comparisons in knee replacement.

Conclusions

The functional status of a large cohort of patients significantly improved after hip and knee replacement based on routine data collection. Our study shows the feasibility of the routine collection of PRO data in patients with total hip and knee replacement. The use of PRO data provides opportunities for continuous quality improvement.

Towards an understanding of the painful total knee: what is the role of patient biology?

Total knee arthroplasty (TKA) remains the treatment of choice for end-stage osteoarthritis of the knee. With an aging population, the demand for TKA continues to increase, placing a significant burden on a health care system that must function with limited resources. Although generally accepted as a successful procedure, 15-30 % of patients report persistent pain following TKA. Classically, pain generators have been divided into intra-articular and extra-articular causes. However, there remains a significant subset of patients for whom pain remains unexplained. Recent studies have questioned the role of biology (inflammation) in the persistence of pain following TKA. This article aims to serve as a review of previously identified causes of knee pain following TKA, as well as to explore the potential role of biology as a predictor of pain following knee replacement surgery.

Long-term mortality and causes of death among patients with a total knee prosthesis in primary osteoarthritis

BACKGROUND

Short and midterm mortality of patients with osteoarthritis (OA) who have undergone total knee arthroplasty (TKA) is generally lower than that of the general population. Due to an increasing number of young patients who undergo TKA the expected lifetime of these patients is increasing. The purpose of this study was to assess the causes of death and long-term mortality among Finnish TKA patients.

METHODS

Standardized mortality ratios (SMRs) for total and site specific causes of death were calculated for 9443 TKA patients operated on in 1980 to 1996 for OA and followed until 2012.

RESULTS

The mean follow-up time was 14 years (maximum 33 years). During follow-up, 77% of the patients had died. The all-cause SMR was 1.00. It was significantly lower than in the reference population (SMR 0.73) during the first 10 years after operation, but higher during the next 10 years (SMR 1.23), and even more after 20 years (SMR 1.95). The SMR for cardiovascular mortality was 1.03 and accounted for 52% of all deaths. Significant excess mortality was observed in diseases of the digestive tract (SMR 1.29). Deaths due to cardiovascular diseases, Alzheimer's disease and dementia comprised 68% of all deaths that took place 10 years or later after TKA.

CONCLUSIONS

The mortality of TKA patients with OA is significantly reduced during the first 10 postoperative years but exceeds the mortality of the general population after that. This trend should be taken into account when young patients undergo a TKA.

LEVEL OF EVIDENCE

Observational study, III.