Total joint arthroplasties: current concepts of patient outcomes after surgery

Complications of Total Joint Arthroplasty in Patients Who Have a History of Coronary Artery Bypass Graft: A Propensity Matched Cohort Study

BACKGROUND

The literature is scarce regarding potential adverse events in patients who have a history of coronary artery bypass graft (CABG) who underwent total joint arthroplasty (TJA). The current study aimed to evaluate postoperative complications in this population.

METHODS

This retrospective cohort study utilized a national database (2010 to 2022) to examine postoperative outcomes in patients who underwent total hip (THA) or knee arthroplasty (TKA) and who had or did not have a history of CABG surgery within three years before arthroplasty. Outcomes of interest included myocardial infarction (MI), cerebrovascular accident (CVA), venous thromboembolism (VTE), acute renal failure (ARF), readmission, transfusion, surgical site infection (SSI), periprosthetic joint infection (PJI), periprosthetic fracture (PPF), and all-cause revision. Propensity score matching was used to control for baseline differences, and multivariate logistic regression was conducted to assess CABG as an independent predictor of postoperative complications.

RESULTS

Patients who had a history of CABG before THA demonstrated significantly higher rates of MI (OR [odds ratio], 2.46; P < 0.001), CVA (OR, 1.36; P = 0.027), and readmission (OR, 1.42; P < 0.001) compared to controls. Similarly, among TKA patients, CABG was associated with increased MI (OR, 2.37; P < 0.001) and CVA rates (1.26; P = 0.049). No significant differences were observed regarding SSI, PJI, PPF, ARF, transfusion rates, or revision rates between CABG and matched control groups.

CONCLUSIONS

Patients who have a history of CABG may have an increased risk of adverse cardiovascular events following TJA, necessitating more intensive postoperative cardiovascular monitoring and care.

LEVEL OF EVIDENCE

III.

Multivariate Profiling of Physical Resilience in Older Adults After Total Knee Replacement Surgery: Results From a Prospective Observational Study

BACKGROUND

As individuals age, their ability to cope with and recover from health challenges becomes vital for maintaining independence and quality of life. This study aims to develop a multivariate phenotype of physical resilience based on individual recovery dynamics before and after a physical stressor.

METHODS

This prospective observational study included 104 individuals aged ≥60 who underwent elective total knee replacement (TKR) for degenerative joint disease between December 2, 2019 and January 4, 2023. A multivariate resilience phenotype was derived from physical function assessments over 12 months after TKR using the Short Physical Performance Battery, the Pittsburgh Fatigability Scale Physical Subscale, the Knee Injury and Osteoarthritis Outcome Quality of Life Score, and the 36-Item Short Form Health Survey Physical Component Score. Validation was performed using markers (ie, frailty and self-reported health) and determinants (eg, the Charlson Comorbidity Index (CCI)) of recovery potential.

RESULTS

Distinct resilience profiles were identified across the 4 measures, showing varied baseline levels and/or change rates over 12 months. By combining and analyzing resilience profiles across measures, 2 distinct groups emerged: 33.7% were classified as nonresilient and 66.4% as resilient. The nonresilient group had a higher prevalence of frailty (37.1% vs 10.1%, p < .01), poor or fair self-reported health (48.6% vs 5.8%, p < .01), and moderate or severe comorbidity burden (CCI > 2; 28.6% vs 10.1%, p = .03).

CONCLUSIONS

Recovery trajectories after TKR revealed varying resilience levels that could not be fully explained by baseline health status. Understanding individual resilience can enhance patient care by promoting recovery and overall well-being.

Impact of Obesity on Joint Replacement Surgery Outcomes: A Comparative Study

BACKGROUND

Obesity negatively impacts joint health and poses challenges during joint replacement surgery, leading to less favorable postoperative outcomes.

OBJECTIVE

This study aims to assess the impact of obesity on postoperative outcomes following joint replacement surgery by comparing obese and non-obese patients.

METHODOLOGY

This prospective observational study was conducted from January 2022 to December 2023, including 186 patients, of which 93 were classified as obese (BMI > 30 kg/m²) and 93 as non-obese (BMI < 30 kg/m²). Data on postoperative complications, mobility, pain scores, comorbidities, and demographics were collected and analyzed using IBM SPSS Statistics for Windows, Version 25.0 (Released 2017; IBM Corp., Armonk, New York, United States). Multivariate logistic regression was employed to identify independent predictors of adverse outcomes.

RESULTS

The mean BMI was significantly higher in obese patients (34.8 ± 3.2 kg/m²) compared to non-obese patients (24.6 ± 2.1 kg/m²). Obese patients had a higher prevalence of severe osteoarthritis (45.16% vs. 26.88%, p = 0.008), longer hospital stays (7.6 ± 2.1 vs. 5.4 ± 1.7 days, p < 0.001), and an increased incidence of postoperative complications, including surgical site infections (11.83% vs. 4.30%, p = 0.05). Multivariate analysis revealed that obesity was an independent predictor of poor postoperative outcomes (OR: 2.40, 95% CI: 1.30-4.50, p = 0.005).

CONCLUSION

Obese patients experienced higher complication rates, greater postoperative discomfort, reduced mobility, and prolonged hospital stays compared to non-obese patients. These findings highlight the significant negative impact of obesity on joint replacement surgery outcomes and emphasize the need for tailored preoperative assessments, optimized perioperative care, and targeted rehabilitation strategies for obese patients.

Differences in kinematics and kinetics during gait between total knee arthroplasty implant designs

BACKGROUND

Implant design is important for achieving proper knee biomechanics during gait following knee arthroplasty. Bicruciate-stabilized total knee arthroplasty attempts to replicate anterior stability and rotational facilitation. However, its detailed gait biomechanics compared with other implant designs have not been analyzed. The purpose of this study is to compare knee kinematics and kinetics between bicruciate-stabilized total knee arthroplasty, posterior-stabilized total knee arthroplasty, unicompartmental knee arthroplasty, and normal knees.

METHODS

Ten healthy subjects, 16 who underwent posterior stabilized total knee arthroplasty, 12 who underwent bicruciate-stabilized total knee arthroplasty, and 13 who underwent unicompartmental knee arthroplasty were recruited. The mean follow-up period after arthroplasty was 11.0 months. Three-dimensional kinematics and kinetics were assessed using a motion capture system with subjects walking on a 5-m walkway. Comparisons between groups were conducted using the Kruskal-Wallis test, and post hoc analysis was performed for those parameters that differed significantly.

FINDINGS

The bicruciate-stabilized total knee arthroplasty group showed decreased internal rotation compared to the unicompartmental knee arthroplasty group. Compared to the control group, the posterior-stabilized total knee arthroplasty group exhibited reduced knee extension and internal rotation moment.

INTERPRETATION

Bicruciate-stabilized total knee arthroplasties exhibited different biomechanical characteristics compared to unicompartmental knee arthroplasties during terminal stance. Postoperative total knee arthroplasty rehabilitation should focus on relieving stiffness owing to insufficient knee flexion-extension motion observed in both bicruciate-stabilized and posterior-stabilized total knee arthroplasties compared with unicompartmental knee arthroplasty, which may be due to a lack of knee rotational motion during gait.

Impact of Preoperative Skeletal Muscle Quality on Functional Outcome in Total Hip Arthroplasty

OBJECTIVES

To investigate the effect of preoperative muscle quality on functional outcomes after total hip arthroplasty (THA).

DESIGN

Retrospective cohort study.

SETTING AND PARTICIPANTS

We included 426 patients who underwent primary THA between 2015 and 2022 to evaluate the relationship between preoperative muscle quality and 1-year functional outcomes following THA.

METHODS

The muscle cross-sectional area (CSA) and density at baseline were measured using preoperative computed tomography. The CSA was further divided based on muscle quality into intramuscular adipose tissue (IMAT), normal-density muscle (NDM), and low-density muscle (LDM) based on muscle density thresholds. According to their functional recovery, patients were classified into sufficient functional recovery [Harris hip score (HHS) ≥89] and insufficient functional recovery (HHS <89) groups based on their HHS at 1-year post THA. Propensity score matching was performed to balance the baseline characteristics of the patient groups, including age, sex, body mass index, HHS, University of California, Los Angeles activity scores, and gait speed. The preoperative muscle density, CSA, IMAT, NDM, and LDM of the gluteus maximus, gluteus medius, gluteus minimus, iliopsoas, and rectus femoris muscles were compared between the groups.

RESULTS

Ninety matched pairs were analyzed following covariate adjustment using propensity scores. The insufficient group had significantly more IMAT in all muscles preoperatively than did the sufficient group (P < .05). In addition, the muscle density and NDM of the gluteus maximus, gluteus medius, and iliopsoas in the insufficient group were significantly worse than those in the sufficient group (P < .05). Conversely, the 2 groups showed no significant differences in LDM.

CONCLUSIONS AND IMPLICATIONS

Our results revealed that patients with a significantly higher IMAT prevalence and reduced NDM preoperatively were less likely to experience significant improvement after THA. Therefore, we propose that undergoing THA with good muscle quality represents the optimal timing for achieving higher functional recovery.

Variation in Demographics, Hospital, and Patient-Reported Outcomes Following Total Hip Arthroplasty According to Biological Sex

BACKGROUND

The effect of biological sex on the outcomes of total hip arthroplasty (THA) remains unclear. Accounting for biological sex in research is crucial for reproducibility and accuracy. Average combined data may mask sex-related variation and obscure clinically relevant differences in outcomes. The aim of this study is to investigate hospital and patient-reported outcome measures (PROMs) after THA by biological sex to elucidate differences and ultimately provide more equitable care.

METHODS

We performed a retrospective review of patients undergoing primary THA at a single large academic center between January 2013 and August 2020. Demographics, operative variables, hospital outcomes, and PROMs were compared between men and women patients. The PROMs included preoperative, 6-weeks, 6-months, and 1-year Single Assessment Numeric Evaluation, Visual Analog Scale, Hip Disability and Osteoarthritis Outcome Score Joint Replacement, University of California, Los Angeles, and Patient-Reported Outcomes Measurement Information System mental and physical scores, as well as satisfaction scores.

RESULTS

A total of 6,418 patients were included (55% women). Women were older (P < .001), had a lower body mass index (P < .001), and were more likely to have public insurance (P < .001). Fewer women were discharged to home or self-care (P < .001). Women had higher rates of cementation (P < .001) and fracture within 90 days (P < .001), and these associations remained significant with adjusted multivariable analyses. Women had significantly higher pain and lower functional scores preoperatively; postoperatively, most PROMs were equivalent.

CONCLUSIONS

Important differences were observed in several areas. Demographic parameters differed, and a variable effect of biological sex was observed on surgical and hospital outcomes. Women had an increased incidence of cemented femoral components (indicated for osteoporotic bone) and postoperative fractures. Women's PROMs demonstrated globally lower functional scores and higher pain preoperatively. Differences attributed to sex should continue to be investigated and accounted for in risk-stratification models. Future studies are needed to elucidate the underlying causes of observed biological sex differences and are essential for equitable arthroplasty care.

Assessment of a New Gait Asymmetry Index in Patients After Unilateral Total Hip Arthroplasty

Background/Objectives: Comparing a given variable between the lower extremities (LEs) usually involves calculating the value of a selected asymmetry index. The aim of this study was to evaluate the mean-dependent asymmetry index for gait variables. Methods: The three-point crutch gait asymmetry between the non-surgical LE (NS) and surgical LE (S) was assessed in 14 patients after unilateral total hip arthroplasty. An eight-camera motion capture system integrated with two force platforms was used. The values of the new gait asymmetry index (MA) were calculated for such variables as stance phase time (ST), knee flexion and extension range of motion (KFE RoM), hip flexion and extension range of motion (HFE RoM), and vertical ground reaction force (VGRF). Results: An analysis related to gait asymmetry showed significantly higher values for all variables for the NS than for the S (the MA ranged from 9.9 to 42.0%; p < 0.001). In the case of comparisons between the MA and other indices, the intraclass correlation coefficient ranged from 0.566 to 0.998 (p < 0.001) with Bland-Altman bias values that ranged from -18.2 to 0.3 %GC (ST), from 0.0 to 0.5° (KFE RoM), from -12.4 to 1.4° (HFE RoM), and from -11.9 to -0.1 %BW (VGRF). Conclusions: The findings revealed a prominent three-point crutch gait asymmetry for all variables, especially a disturbingly large asymmetry for the HFE RoM and VGRF. The comparisons also showed generally excellent or good agreement with the other indices. Furthermore, the mean MA result from n single values was the same as the MA result calculated using the mean values of a given variable. The MA, as an accurate asymmetry index, can be used to objectively assess pathological gait asymmetry.

Mechanical complications and revision following total joint arthroplasty in acromegalic patients: A nationwide US-based study

BACKGROUND

Acromegaly is associated with significant osteoarthritis (OA) and increased risk of vertebral and hip fractures. There is limited data on total joint arthroplasty (TJA) outcomes in patients with acromegaly.

METHODS

In this retrospective study, we identified patients with acromegaly who underwent total hip arthroplasty (THA), total knee arthroplasty (TKA), and total shoulder arthroplasty (TSA) between 2010 and 2022 using the PearlDiver national database. Patients with a prior history of osteoporosis and follow-up duration of less than one year were excluded. Non-acromegalic control groups were selected through matching based on confounding factors. We compared all-cause revision and implant-related complications between the groups using R software integrated with the PearlDiver database.

RESULTS

We identified 1440 patients with acromegaly: 665 underwent THA, 618 underwent TKA, and 157 underwent TSA. Compared to the control group (2634 THA, 2445 TKA, and 600 TSA), there was no significant association with post-op revision following THA (OR(1-year) = 0.76[0.42-1.28], OR(5-year) = 0.68[0.42-1.06]), TKA (OR(1-year) = 0.89[0.48-1.55], OR(5-year) = 0.78[0.49-1.17]), and TSA (OR(1-year) = 0.19[0.02-1.40], OR(5-year) = 0.32[0.10-1.07]). Additionally, the risk of mechanical complications did not significantly increase in patients with acromegaly, either one year or five years post-operation.

CONCLUSION

The study showed no significant increase in risk of revisions or mechanical complications in patients with acromegaly compared to controls. These findings bridge an important gap in the understanding of post-arthroplasty complications in patients with acromegaly and offer valuable insights into surgical expectations.

The effect of copper and vitamin D on osteoarthritis outcomes: A Mendelian randomization study

This study aimed to explore the causal relationship between trace elements and osteoarthritis (OA). The results showed a relatively weak association between copper and OA, while vitamin D showed a significant positive association with OA. Mendelian randomization (MR) analysis was used to investigate the causal relationship between copper and vitamin D and OA. A variety of MR methods including inverse variance weighting, weighted median, MR-Egger, simple model, and multi-text mixed model were analyzed to confirm the consistency of these results. Sensitivity analysis further confirmed the reliability of these causal relationships and excluded the interference of pleiotropy. These findings add to the understanding of the potential role of micronutrients in the prevention and treatment of OA and support the idea of vitamin D as a potential therapy for the prevention and treatment of OA. Future studies should further explore the specific biological mechanisms of these trace elements and the differences in their effects in different populations in order to develop more effective treatment strategies to reduce the health burden of degenerative joint diseases.

A Readmission Risk Assessment Tool Is Not Predictive of 90-Day Readmission After Total Joint Arthroplasty at an Urban Tertiary Referral Hospital

INTRODUCTION

Readmission within 90 days of total joint arthroplasty (TJA) via an emergency department (ED) encounter represents a significant economic burden to the healthcare system. We aimed to determine the utility of a previously described readmission risk assessment tool (RRAT) in predicting readmission after presentation to the ED within 90 days of primary TJA.

METHODS

At a single academic tertiary referral medical center, a retrospective chart review was used to collect demographic data, surgery type, medical history, reason for presentation in the ED, and ED disposition for the 1,576 patients who underwent TJA between April 1, 2016, and December 31, 2018. The RRAT score of patients was calculated and compared between patients who were discharged home versus readmitted to inpatient care.

RESULTS

We identified 244 patients (328 encounters) who presented to the ED within 90 days of primary TJA, resulting in a 3.1% readmission rate. No statistical difference was found between the RRAT scores of readmitted and discharged patients (p=0.24). The most common reason for presentation to the ED for discharged patients was surgical site pain compared to medical concerns (cardiac, hematological, and renal concerns) in the readmitted group.

CONCLUSIONS

Although the RRAT score alone is not predictive of readmission within 90 days of TJA, the reason for presentation to the ED between discharged and readmitted patients does differ. These results present an opportunity for orthopedic surgery providers to discuss with other providers ways to optimize postoperative pain management and decrease readmissions. This study underscores the need for improved postoperative pain and chronic condition management to reduce ED visits and readmissions and highlights the necessity for larger, multi-center studies to better assess the RRAT score's predictive value.

Direct Anterior Approach in Total Hip Arthroplasty: A Single Center Experience

Purpose

The direct anterior approach (DAA) for conducting total hip arthroplasty (THA) is gaining popularity worldwide. However, careful selection of patients and surgeon experience are important. Although promising outcomes have been reported in international studies, research on DAA in Southern and Southeast Asia has been limited.

Materials and Methods

This prospective study included 157 patients who underwent THA using the DAA between January 2019 and June 2022. The patients were divided into three groups for the comparison. Data on preoperative, intraoperative, and postoperative variables were acquired. Improvement of the surgeon's performance to use of a DAA approach was examined using the CUSUM (cumulative summation method).

Results

The mean age of the patients was 43.9 years. Differences in intraoperative variables and complications were observed among the three groups, and improved outcomes were reported in later cases. Functional outcomes showed significant improvement, and no differences were observed between groups. The results of learning curve analysis indicated a shift towards consistent success after the 82nd case, reaching an acceptable rate of failure by the 118th case.

Conclusion

The findings of this study suggest that DAA can offer benefits but there is a learning curve. Complications were initially high but began decreasing after approximately 80 cases. Careful selection of patients is critical, particularly in the effort to minimize being presented with a challenging case. This study provides insights that may be helpful to surgeons when considering DAA; however, further study is warranted.

Patient satisfaction and patient-reported outcomes do not vary by BMI class in total hip arthroplasty

PURPOSE

Obesity has been identified as a risk factor for postoperative complications in patients undergoing total hip arthroplasty (THA). This study aimed to investigate patient-reported outcomes, pain, and satisfaction as a function of body mass index (BMI) class in patients undergoing THA.

METHODS

1736 patients within a prospective observational study were categorized into BMI classes. Pre- and postoperative Hip disability and Osteoarthritis Outcome Score for Joint Replacement (HOOS JR), satisfaction, and pain scores were compared by BMI class using one-way ANOVA.

RESULTS

Healthy weight patients reported the highest preoperative HOOS JR (56.66 ± 13.35) compared to 45.51 ± 14.45 in Class III subjects. Healthy weight and Class III patients reported the lowest (5.65 ± 2.01) and highest (7.06 ± 1.98, p < 0.0001) preoperative pain, respectively. Changes in HOOS JR scores from baseline suggest larger improvements with increasing BMI class, where Class III patients reported an increase of 33.7 ± 15.6 points at 90 days compared to 26.1 ± 17.1 in healthy weight individuals (p = 0.002). Fewer healthy weight patients achieved the minimal clinically important difference (87.4%) for HOOS JR compared to Class II (96.5%) and III (94.7%) obesity groups at 90 days postoperatively. Changes in satisfaction and pain scores were largest in the Class III patients. Overall, no functional outcomes varied by BMI class postoperatively.

CONCLUSION

Patients of higher BMI class reported greater improvements following THA. While risk/benefit shared decision-making remains a personalized requirement of THA, this study highlights that utilization of BMI cutoff may not be warranted based on pain and functional improvement.

Impact of acetabular roof's angle on precision of cup center of rotation reproduction and placement in total hip arthroplasty

Introduction

Total hip arthroplasty (THA) is nowadays considered as the most effective treatment option for end-stage hip osteoarthritis (OA) and one of the most successful orthopedic procedures. Precise reproduction of the center of rotation (COR) is among the most important aspects of recreating native hip biomechanics after THA as it is strictly related to muscle tension and force distribution within the hip joint. Both vertical and horizontal shift in cup positioning and COR restoration are commonly observed radiological signs corresponding with lesser functional outcome. The aim of this study was to assess whether the superior border of the native acetabulum morphology has an impact on cup positioning and COR restoration in patients undergoing THA as treatment of primary OA of the hip.

Material and methods

A cohort of 150 consecutive patients with diagnosis of end-stage primary hip OA who underwent THA via an anterolateral approach with the same implant in 2021 was analyzed retrospectively. Standard standing pelvic X-rays were performed pre- and postoperatively and appropriate measurements were taken. Several radiological parameters on obtained X-rays were assessed. Statistical analysis of all the measurements was performed.

Results

There was a statistically significant positive weak correlation between cup offset and acetabular roof angle (rs = 0.25, p = 0.002). There were statistically insignificant positive correlations between acetabular roof angle and COR restoration (rs = 0.14, p = 0.097), acetabular roof angle and total offset (rs = 0.087, p = 0.29) and a negative correlation between acetabular roof angle and femoral offset (rs = 0.071, p = 0.39).

Conclusions

The present study revealed that preoperative acetabular roof angle influences the positioning of the prosthetic cup in the transverse axis. There also seems to be a correlation between the acetabular roof angle and COR restoration, but its significance needs further evaluation. Surgeons could use this knowledge to preoperatively assess the risk of cup malposition and adjust their technique during the THA procedure with probable improvement of hip function.

The contribution of metal allergy to the failure of metal alloy implants, with special reference to titanium: Current knowledge and controversies

After almost three-quarters of a century during which contact dermatologists have often struggled to comprehend the relationship between metal allergy and failure of metal-alloy containing implant, it is possible to say that a relationship does exist, particularly for cobalt and chromium, but also for nickel. There is still debate as to whether allergy develops as a consequent of failure but thenceforth contributes to it, or whether sensitisation starts first and induces failure secondarily-opinion probably favours the first. Metal-on-polypropylene articulations were associated with few metal allergic problems but now are less favoured by orthopaedists due to plastic wear products causing osteolysis and pseudotumour formation through local inflammation. New metal alloys are regularly being introduced such that interested dermatologists need to stay on top of the situation. The jury is still out as to whether the recent favouring of titanium-containing alloys will confirm them to be more inert allergenically. Case reports do show some clinical reactions to titanium-containing implants and patch test series have inferred sometimes quite a high background rate of allergy, but interpretation must be tempered by the awareness that titanium salts on patch testing have a tendency to cause irritant reactions. Blood monitoring of metal ion values is now recommended in certain situations after joint replacement and increasing levels may be an indication that allergy with joint failure can develop, in which case patch testing is indicated, and suggested series are available. Predictive patch testing, whilst generally not recommended in the past, has been introduced into some protocols often by non-dermatologists, such that it is now needed for temporo-mandibular joint and Nuss bar insertion, and it can be anticipated that this may become more commonplace in the future. One of the major current deficits for patch testers is standardised guidance on which preparation or preparations to use for suspected titanium allergy. One suggestion is 0.5% titanium sulphate in petrolatum, though experience in at least one centre suggests the use of a battery of titanium salts might be desirable.

Using Unsupervised Machine Learning to Predict Quality of Life After Total Knee Arthroplasty

BACKGROUND

Patient-reported outcome measures (PROMs) are an important metric to assess total knee arthroplasty (TKA) patients. The purpose of this study was to use a machine learning (ML) algorithm to identify patient features that impact PROMs after TKA.

METHODS

Data from 636 TKA patients enrolled in our patient database between 2018 and 2022, were retrospectively reviewed. Their mean age was 68 years (range, 39 to 92), 56.7% women, and mean body mass index of 31.17 (range, 16 to 58). Patient demographics and the Functional Comorbidity Index were collected alongside Patient-Reported Outcome Measures Information System Global Health v1.2 (PROMIS GH-P) physical component scores preoperatively, at 3 months, and 1 year after TKA. An unsupervised ML algorithm (spectral clustering) was used to identify patient features impacting PROMIS GH-P scores at the various time points.

RESULTS

The algorithm identified 5 patient clusters that varied by demographics, comorbidities, and pain scores. Each cluster was associated with predictable trends in PROMIS GH-P scores across the time points. Notably, patients who had the worst preoperative PROMIS GH-P scores (cluster 5) had the most improvement after TKA, whereas patients who had higher global health rating preoperatively had more modest improvement (clusters 1, 2, and 3). Two out of Five patient clusters (cluster 4 and 5) showed improvement in PROMIS GH-P scores that met a minimally clinically important difference at 1-year postoperative.

CONCLUSIONS

The unsupervised ML algorithm identified patient clusters that had predictable changes in PROMs after TKA. It is a positive step toward providing precision medical care for each of our arthroplasty patients.

Predictors of postoperative hospital length of stay after total knee arthroplasty

INTRODUCTION

We aimed to collect and analyse clinical and functional variables of patients undergoing rehabilitation after total knee arthroplasty (TKA), to identify the variables that influence the postoperative hospital length of stay (LOS).

METHODS

We conducted a retrospective analysis of prospectively collected data of 1,082 consecutive patients (746 females and 336 males) who underwent primary TKA and rehabilitation in our orthopaedic institute between January 2013 and July 2017. Clinical and anthropometric data were analysed using a multivariate linear regression model.

RESULTS

The average LOS was 5.08 ± 2.52 days in the Department of Orthopaedic Surgery and 12.67 ± 5.54 days in the Sports Rehabilitation Unit. Factors such as age, female sex and the presence of comorbidities were predictive of a longer stay. The presence of caregiver assistance at home was associated with shorter LOS. There was no evidence of a statistically significant positive association between body mass index and LOS.

CONCLUSION

An in-depth and early knowledge of factors that influence LOS may enable the multidisciplinary team to plan a patient-tailored rehabilitation path and better allocate resources to maximise patients' functional recovery, while reducing LOS and the overall cost of the procedure.

Incidence of Postoperative Infection Following Simultaneous Bilateral Knee Arthroplasty: A Systematic Review and Meta-Analysis

Total knee arthroplasty is one of the most common orthopedic procedures. Simultaneous bilateral knee arthroplasty involves performing total knee arthroplasty on both knees in a single anesthetic session. This systematic review and meta-analysis followed the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020. A primary search was performed using PubMed, EBSCO, Scopus, Web of Science, Clarivate, and Google Scholar databases. Quantitative data synthesis was performed using MedCalc® Statistical Software version 20.115 to determine the pooled prevalence of the infection among patients who underwent simultaneous bilateral knee arthroplasty. The Newcastle-Ottawa Scale was used to assess study quality. We included 30 studies in our quantitative data synthesis, with a total population of 118,502 patients (237,004 knees). The pooled prevalence of superficial infection, deep infection, and unspecified surgical site infection was estimated to be 0.86% (95% confidence interval: 0.62-1.13%), 0.84% (95% confidence interval: 0.64-1.05%), and 1.18% (95% confidence interval: 0.45-2.27%), respectively. There was significant heterogeneity (I2 >50%) in all analyses, and inspection of funnel plots revealed a symmetrical distribution of plotted data. We found that the infection rates following simultaneous bilateral knee arthroplasty were relatively low but heterogeneous, as the data showed marked variability. Superficial infections were more common than deep infections; however, there was a small difference in their prevalence. Furthermore, the reliability of our findings was limited owing to significant heterogeneity.

The influence of direct anterior approach and postero-lateral approach on wound complications after total hip arthroplasty: A meta-analysis

To date, we have reviewed the synthesis literature critically through four databases: PubMed, Embase, Cochrane Library and Web of Science. Eight relevant studies were examined after compliance with the criteria for inclusion and exclusion, as well as documentation quality evaluation. This report covered all randomised, controlled studies of total hip arthroplasty (THA) comparing the direct anterior approach (DAA) with the postero-lateral approach (PLA). The main result was surgical site infection rate. The secondary results were duration of the operation, length of the incision and VAS score after surgery. The results of the meta-analyses of wound infections in the present trial did not show any statistically significant difference in DAA versus PLA (between DAA and PLA) (OR = 1.42, 95%CI: 0.5 to 4.04, p = 0.51). Compared with PLA, DAA had shorter surgical incision (WMD = -3.2, 95%CI: -4.00 to -2.41; p < 0.001) and longer operative times(WMD = 14. 67, 95%CI: 9.24 to 20.09; p < 0.001). Postoperative VAS scores were markedly lower in DAA compared with PLA within 6 weeks of surgery (p < 0.05), with low heterogeneities(I2  = 0). We found that DAA did not differ significantly from PLA in terms of the risk of wound infection for THA and that the surgical incisions was shorter and less postoperative pain after surgery, even though DAA surgery takes longer.

Use of analgesics before and after total joint replacement in working-age Japanese patients with knee and hip osteoarthritis: A retrospective database study

Background

Patterns of analgesic use before and after total joint replacement (TJR) in patients with knee/hip osteoarthritis (OA) is not well reported.

Methods

This retrospective longitudinal analysis used JMDC claims data of patients who underwent knee/hip replacement surgery from 2010 to 2019. Primary outcome was proportion of patients using analgesics pre-surgery, immediately post-surgery, and in post-surgery period. Factors affecting post-surgery analgesic withdrawal and opioid prescriptions were assessed using logistic regression.

Results

Of all (N = 3168) patients, those with knee OA (91.1 %) and hip OA (82.5 %) used analgesics pre-surgery, and 96.1 % with knee OA and 84.9 % with hip OA required analgesics even 3 months post-surgery. NSAIDs were most commonly used pre- and post-surgery in both OA groups. Before surgery, 15.6 % (knee OA) and 13.7 % of patients (hip OA) used weak opioids, and 23.1 % (knee OA) and 10.5 % (hip OA) of patients continued them post-surgery. Strong opioid use was noted in 2.2 % and 1.2 % of patients pre-surgery, and 5.8 % and 3.4 % of patients post-surgery in the knee and hip OA groups, respectively. Using pre-operative oral NSAIDs (odds ratio [OR]:0.56; 95 % confidence interval [CI]:0.44-0.72) and weak opioids (OR:0.58; 95 % CI:0.38-0.87) associated with withdrawal of post-surgery analgesics in patients with hip OA, and using intra-articular hyaluronic acid pre-surgery (OR:0.45; 95 % CI:0.21-0.97) was significant in patients with knee OA. Using weak (OR:4.59; 95 % CI:3.44-6.13) and strong opioids (OR:2.48; 95 % CI:1.01-6.07) pre-surgery associated with post-operative opioid use in patients with hip OA, and weak opioid use was significant in patients with knee OA (OR:7.00; 95 % CI:4.65-10.54).

Conclusion

This study reported difference in analgesic use before and after TJR, and that many patients required analgesics even 3 months after TJR surgery in Japan. Pre-operative analgesic use associated with continued use after surgery. Optimal pain management before and immediately after TJR is important to reduce post-operative analgesic use, especially opioids.

Does an Adductor Canal Block Influence Patient-Reported Outcomes at One Year Following Total Knee Arthroplasty?

Introduction Total knee arthroplasty (TKA) for osteoarthritis is performed to improve knee function and quality of life. Adductor canal block (ACB) (with posterior capsule local anaesthetic) and periarticular local anaesthetic infiltration (LA) alone are common methods used for post-operative pain control following TKA. The primary aim of this study was to investigate the influence of ACB compared to LA alone on knee function at one year in patients undergoing primary TKA. The secondary aims were to investigate the influence on health-related quality of life (HRQoL), patient satisfaction at one year, and length of stay (LOS) in hospital following TKA. Methods During a three-year period, 1396 patients who underwent TKA at the study centre completed pre-operative and one-year post-operative questionnaires. Data collected included patient demographics, co-morbidities, LOS, Oxford Knee Score (OKS), EuroQol 5-Dimension (EQ-5D) and satisfaction scores. Patients who had a spinal anaesthetic (n=1096) with either ACB (with posterior capsule local anaesthetic) (n=224) and LA infiltration alone (n=872) were compared. Results There was a significant improvement in pre-operative to one-year post-operative knee function as measured by OKS overall (15.1, p<0.001), however there was no significant difference between ACB and LA groups (p=0.37). There was no significant difference in change (p=0.43) or one-year post-operative (p=0.70) HRQoL, as measured by EQ-5D. There was also no significant difference in one-year patient satisfaction between groups (p=0.57). There was no significant difference in median LOS between groups (four days with ACB, four days with LA), although patients younger than 55 years undergoing ACB had a statistically significant median of one day reduced LOS compared with the LA group (p=0.01). Conclusions ACB when compared with LA alone was not associated with a difference in change in knee function, HRQoL, or patient satisfaction at one year following TKA. There was also no difference between groups in length of stay post-operatively. However, ACB was associated with a shorter length of stay in patients younger than 55, and this may be a group that would benefit from this intervention.

Long-term health related quality of life in total knee arthroplasty

BACKGROUND

To analyze evolution and factors related with greater gains in Health Related Quality of Life (HRQOL) and with a greater probability of exceed their corresponding minimal clinically important differences (MCID) in patients with Osteoarthritis of the knee, undergoing total knee arthroplasty (TKA) at long-term.

METHODS

Data were obtained from two previously recruited multicenter cohorts of patients who underwent TKA in the Basque Country. Patients were follow-up at 6 months and 10 years after surgery. Patients completed specific and generic HRQOL questionnaires plus sociodemographic, and clinical data at 10 years. Associations were analysed using linear and logistic regression models.

RESULTS

A total of 471 patients responded at 10-year follow-up. The multivariable analysis showed that low preoperative HRQOL scores, higher age, higher BMI, some comorbidities and readmissions at 6 months were associated with less gains in HRQOL. Apart from aforementioned, to have a peripheral vascular disease (odd ratio 0.49 (95% CI, 0.24-0.99)), complications (odd ratio 0.31 (95% CI, 0.11-0.91)), and readmissions within 6 months of discharge (odd ratio 2.12 (95% CI, 1.18-3.80)) were associated with a lower probability of exceeding the MCID. The effect sizes (ESs) of changes from baseline to 6 months (range, 1.20-1.96) and to 10 years (range, 1.54-1.99) were large in all dimensions, nevertheless the ESs from 6 months to 10 years were not appreciable for pain (ES = 0.03) or stiffness (ES = 0.09), and small for function (ES = 0.30).

CONCLUSIONS

Low preoperative HRQOL scores, to be elderly, severe obesity, the presence of some comorbidities -depression and rheumatology disease-, having readmissions or complications and not having rehabilitation of discharge, are good predictors of long-term lower gains in HRQOL. Some other non-registered parameters of the follow-up may also influence those outcomes.

KEY INDEXING TERMS (MESH TERMS)

Health-Related Quality of Life, Knee Arthroplasty, Total, Osteoarthritis.

Fire Needling Therapy of Different Frequencies versus External Diclofenac Diethylamine Emulgel for Knee Osteoarthritis: Study Protocol for a Pilot Randomized Controlled Trial

Purpose

Knee osteoarthritis (KOA) is regarded as one of the leading musculoskeletal diseases. Although the efficacy is under exploration, fire needling therapy is considered an effective alternative for KOA. This trial aims to investigate the effectiveness of different frequencies of fire needling therapy in attenuating pain and promoting function in KOA patients.

Methods

This is a study protocol for a pilot, three-arm, single-center, randomized controlled trial. A total of 90 participants with KOA will be recruited and randomly assigned to the high-frequency fire needling group (3 sessions per week, for 6 weeks), the low-frequency fire needling group (1 session per week, for 6 weeks) or the positive control group (Diclofenac Diethylamine Emulgel, 3 times per day, for 6 weeks) in a 1:1:1 ratio. Participants will accomplish the trial at Week 14 after a follow-up evaluation. The response rate will be set as the primary outcome that the proportion of participants obtaining a minimal clinically important difference, which is identified as ≥2 units on the numerical rating scale (NRS) and ≥6 units on the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) function score at Week 6 compared with Week 0. Secondary outcomes are NRS, WOMAC, Brief Pain Inventory, Short-Form Health Survey-12, Timed Up and Go Test, and pain threshold.

Discussion

This is the first standardized protocol comparing fire needling therapy and positive control drugs. This trial may provide reliable evidence for the effectiveness of fire needling therapy and dose-effect property of it in KOA. Trial registration: The trial has been registered on Chinese Clinical Trial Registry (Registered number: ChiCTR2100043041), registered on 4 February 2021.

Total Hip Arthroplasty via direct anterior approach for osteonecrosis; comparison with primary hip osteoarthritis in a mid term follow up

BACKGROUND

To determine the mid-term outcomes of conventional cementless Total Hip Arthroplasty (THA) in patients with avascular necrosis (AVN) of the femoral head and compare to patients with primary hip osteoarthritis (OA).

METHOD

A total of 330 consecutive primary THA procedures (AVN and OA) performed between 2010 and 2013 by a single surgeon and in a single center using the direct anterior approach (DAA) were included. Assessments including SF-36, WOMAC, and Harris Hip Scores (HHS) were retrieved from patients before the surgery and at the latest follow-up. Clinical and functional outcomes were compared between the AVN and OA groups.

RESULTS

A total of 294 consecutive THA (AVN = 107, OA = 187) with 104.4 ± 6.2 months follow-up were analyzed, which AVN patients were significantly younger (32.0 vs. 59.6 y/o). Corticosteroid 34 (31.8%), idiopathic AVN 31 (29.0%) and use of unapproved weight gain supplements (UWGS) 23 (21.5%) were the main reasons for AVN. Despite that preoperative scores were comparable (P > 0.05), the HHS, SF-36, and WOMAC scores are significantly higher in the AVN group after THA surgery (P < 0.05). Moreover, flexion and abduction ROM were significantly higher in the AVN group (P < 0.05). Regarding each complication, no significant difference was observed between groups. In the whole sample, there were 5 (1.7%) revisions due to loosening of acetabular components, all the OA group (P > 0.05).

CONCLUSION

Conventional cementless THA with highly cross-linked polyethylene provides satisfactory mid-term results in patients with AVN with a low rate of postoperative complications. Compared to primary OA patients, this group reaches superior postoperative scores.

Appraisal and patient-reported outcomes following total hip arthroplasty: a longitudinal cohort study

Background

Total hip arthroplasty (THA) is a successful procedure that provides pain relief, restores function, and improves quality of life (QOL) for patients with advanced arthritis in their hip joint. To date, little research has examined the role of cognitive appraisal processes in THA outcomes. This study examined the role of cognitive appraisal processes in THA outcomes in the first year post-surgery.

Methods

This longitudinal cohort study collected data at pre-surgery, 6 weeks post-surgery, 3 months post-surgery, and 12 months post-surgery. Adults (n = 189) with a primary diagnosis of osteoarthritis were consecutively recruited from an active THA practice at a Canadian academic teaching hospital. Measures included the Hip Disability and Osteoarthritis Outcome Score (HOOS), the Mental Component Score (MCS) of the Rand-36, and the Brief Appraisal Inventory (BAI). Analysis of Variance examined the association between BAI items and the HOOS or MCS scores. Random effects models investigated appraisal main effects and appraisal-by-time interactions for selected BAI items.

Results

HOOS showed great improvement over the first 12 months after THA, and was mitigated by three appraisal processes in particular: focusing on problems with healthcare or living situation, and preparing one’s family for health changes. MCS was stable and low over time, and the following appraisal processes were implicated by very large effect sizes: not comparing themselves to healthier people, focusing on money problems, preparing their family for their health changes, or trying to shed responsibilities.

Conclusions

Appraisal processes are relevant to health outcomes after THA, with different processes coming into play at different points in the recovery trajectory.

Supplementary Information

The online version contains supplementary material available at 10.1186/s41687-022-00498-z.

The intraoperative hip range of motion in total hip arthroplasty predicts postoperative patient's satisfaction for cutting toenails and putting on sock

BACKGROUND

Restricted hip range of motion (ROM) has been proposed as a useful diagnostic tool for osteoarthritis. The relations between the intraoperative hip ROM under anesthesia in total hip arthroplasty (THA) and recovery of clinical mobility outcomes were unclear. This study evaluated the association between the intraoperative hip ROM under anesthesia in THA and the postoperative recovery of clinical mobility, including cutting toenails and putting on socks after THA.

METHODS

The study was performed as a prospective cohort study and included 93 hips in 85 patients who underwent primary anterior-based muscle-sparing THA in the supine position. The hip ROM was evaluated under anesthesia before skin incision and intraoperative stability test. The Japanese Orthopaedic Association Hip-Disease Evaluation Questionnaire (JHEQ) was evaluated. A questionnaire on whether and how patients could cut toenails and putting on socks was assessed. The relationship between hip ROM at intraoperative stability tests and JHEQ moving score, cutting toenails, and putting on socks scores were evaluated statistically.

RESULTS

We observed a week positive correlation between intraoperative hip ROM and the total of JHEQ mobility score. A moderate positive correlation was observed between external rotation angle with flexion 90°and cutting toenails and putting on socks score oh JHEQ. 94.6% and 96.8% of the patients could cut their toenails and putting on socks by themselves after surgery. The optimum cutoff range for high patient satisfaction for putting on socks and cutting toenails was 110° for flexion and 35°-40° for the external rotation angle in the intraoperative stability test.

CONCLUSION

Hip ROM during intraoperative stability testing, especially the external rotation angle can predict postoperative outcomes and patient satisfaction for cutting toenails and putting on socks. We suggested that the capsule or capsular ligament release around the hip was increased to provide sufficient ROM without compromising stability.

Does obesity lead to lower rates of clinically meaningful improvement or satisfaction after total hip arthroplasty? A propensity score-matched study

BACKGROUND

Current literature lacks consensus regarding the impact of obesity on clinical outcomes of total hip arthroplasty (THA). The variability of results may reflect the lack of minimal clinically important difference (MCID) analysis, which helps to standardise the interpretation of patient-reported outcome measures (PROMs). We compared the PROMs, patient satisfaction and survivorship between obese and non-obese patients after THA.

METHODS

Prospectively collected registry data of 192 obese patients and 192 propensity score-matched controls who underwent primary THA at a single institution were reviewed. Clinical outcomes and satisfaction rates were assessed at 6 months and 2 years. Reoperations for surgical complications and revision rates were analysed.

RESULTS

Obese patients had a significantly poorer Oxford Hip Score (OHS) at 6 months and WOMAC-Function at 2 years. However, there was no difference in overall WOMAC, WOMAC-Pain, WOMAC-stiffness, SF-36 mental and physical component summary (PCS). A similar proportion of patients in each group achieved the MCID for OHS, WOMAC and SF-36 PCS. At 2 years, 90.3% of obese patients and 91.7% of controls were satisfied (p = 0.755). At a mean follow-up of 9 years, there were 5 reoperations (2.6%) for surgical complications in the obese group and 1 (0.5%) in the control group; whereas 12 revisions (6.3%) were recorded in the obese group and 3 (1.6%) in the control group (p = 0.021).

CONCLUSIONS

Despite a higher revision rate, obese patients undergoing THA may experience a similar level of clinical meaningful improvement and satisfaction as their non-obese counterparts. This study provides valuable prognostic information for obese patients and guides preoperative counselling.

The potential risk of using historic claims to set bundled payment prices: the case of physical therapy after lower extremity joint replacement

Background

One of the most significant challenges of implementing a multi-provider bundled payment contract is to determine an appropriate, casemix-adjusted total bundle price. The most frequently used approach is to leverage historic care utilization based on claims data. However, those claims data may not accurately reflect appropriate care (e.g. due to supplier induced demand and moral hazard effects). This study aims to examine variation in claims-based costs of post-discharge primary care physical therapy (PT) utilization after total knee and hip arthroplasties (TKA/THA) for osteoarthritis patients.

Methods

This retrospective cohort study used multilevel linear regression analyses to predict the factors that explain the variation in the utilization of post-discharge PT after TKA or THA for osteoarthritis patients, based on the historic (2015–2018) claims data of a large Dutch health insurer. The factors were structured as predisposing, enabling or need factors according to the behavioral model of Andersen.

Results

The 15,309 TKA and 14,325 THA patients included in this study received an average of 20.7 (SD 11.3) and 16.7 (SD 10.1) post-discharge PT sessions, respectively. Results showed that the enabling factor ‘presence of supplementary insurance’ was the strongest predictor for post-discharge PT utilization in both groups (TKA: β = 7.46, SE = 0.498, p-value< 0.001; THA: β = 5.72, SE = 0.515, p-value< 0.001). There were also some statistically significant predisposing and need factors, but their effects were smaller.

Conclusions

This study shows that if enabling factors (such as supplementary insurance coverage or co-payments) are not taken into account in risk-adjustment of the bundle price, they may cause historic claims-based pricing methods to over- or underestimate appropriate post-discharge primary care PT use, which would result in a bundle price that is either too high or too low. Not adjusting bundle prices for all relevant casemix factors is a risk because it can hamper the successful implementation of bundled payment contracts and the desired changes in care delivery it aims to support.

Factors affecting short-term functional gain following total knee arthroplasty in patients aged from 75 years at a postacute rehabilitation setting

The intensive rehabilitation of older patients after total knee arthroplasty (TKA) is vital for short-term improvement in mobility and daily living activities. We aimed to investigate the effectiveness of multidisciplinary rehabilitation and assess the early postoperative predictors that are associated with functional gain in TKA patients aged from 75 years in a postacute care setting. This study included 190 patients following primary TKA who were admitted at the postacute rehabilitation hospital. The main outcome measures were the motor component of functional independence measure (M-FIM), M-FIM effectiveness, numerical rating scale, knee extension strength and range of motion, 10-m walk test, Berg balance scale (BBS), and mini-mental state examination (MMSE). The functional gain between patient age groups of ≥75 (n = 105) and <75 (n = 85) years were compared. Although patients aged ≥75 years showed lower improvement in BBS score compared with <75 years, the M-FIM gains and other physical functions were similar in both age groups. In multivariate analysis, the results for M-FIM at admission (β: -0.703; P = 0.001), BBS (β: 0.342; P = 0.032) and MMSE (β: 0.446; P = 0.021) were independently associated with functional gain in the patients following TKA aged ≥75 years. Multidisciplinary inpatient rehabilitation was beneficial for basic functional gain except for improvement in balance ability in patients after TKA aged ≥75 years. Functional level, balance ability and cognitive status in the early postoperative period can be useful predictors for short-term functional gain in the postacute care phase.

Small molecules of herbal origin for osteoarthritis treatment: in vitro and in vivo evidence

Osteoarthritis (OA) is one of the most common musculoskeletal degenerative diseases and contributes to heavy socioeconomic burden. Current pharmacological and conventional non-pharmacological therapies aim at relieving the symptoms like pain and disability rather than modifying the underlying disease. Surgical treatment and ultimately joint replacement arthroplasty are indicated in advanced stages of OA. Since the underlying mechanisms of OA onset and progression have not been fully elucidated yet, the development of novel therapeutics to prevent, halt, or reverse the disease is laborious. Recently, small molecules of herbal origin have been reported to show potent anti-inflammatory, anti-catabolic, and anabolic effects, implying their potential for treatment of OA. Herein, the molecular mechanisms of these small molecules, their effect on physiological or pathological signaling pathways, the advancement of the extraction methods, and their potential clinical translation based on in vitro and in vivo evidence are comprehensively reviewed.

Effects of Comorbidities on Pain and Function After Total Hip Arthroplasty

Background

The growing number of patients undergoing total hip arthroplasty (THA) and postoperative outcomes receive increasing attention from doctors and patients. This study aimed to elucidate the effects of comorbidities on postoperative function, pain, complications, readmission rate, and mortality.

Methods

We included consecutive patients who underwent primary unilateral THA between 2017 and 2019. The Charlson comorbidity index (CCI) and the WOMAC and SF-36 (physical function, body pain) scales were assessed preoperatively and at 3, 6, 12, and 24 months postoperatively. The complications, 30-day readmission, and mortality rates assessed the impact of comorbidities and their changes over time on the WOMAC and SF-36 scores during follow-up. We used mixed model linear regression to examine the association of worsening comorbidity post-THA with change in WOMAC and SF-36 scores in the subsequent follow-up periods, controlling for age, length of follow-up, and repeated observations.

Results

This study included 468 patients, divided into four groups based on comorbidity burden (CCI-0, 1, 2, and ≥3). The physiological function recovery and pain scores in the CCI ≥ 3 group were inferior to the other groups and took longer than the other groups (6 vs. 3 months) to reach their best level. The four groups preoperative waiting times were 2.41 ± 0.74, 2.97 ± 0.65, 3.80 ± 0.53, and 5.01 ± 0.71 days, respectively. The complications, 30-day readmission, and 1-year mortality rates for the overall and the CCI ≥ 3 group were 1.92% and 4.69%, 0.85% and 2.01%, and 0.43% and 1.34%, respectively, with no mortality in the other groups.

Conclusion

Patients with higher CCI were more susceptible to physical function and pain outcome deterioration, experienced longer waiting time before surgery, took longer to recover, and had higher rates of complications, 30-day readmission, and mortality after THA. Older age in the group led to a greater impact.

Analysis of factors influencing patient satisfaction after total hip arthroplasty in a Japanese cohort: the significant effect of postoperative physical activity

[Purpose] To determine patient satisfaction after total hip arthroplasty in a Japanese cohort and to identify factors that significantly influence patient satisfaction. [Participants and Methods] This study included 285 patients who underwent primary total hip arthroplasty for osteoarthritis. Postoperative satisfaction, Oxford hip score, short form-12 mental component summary score, and University of California Los Angeles activity score were investigated. Muscle strength and daily step counts were determined using a hand-held dynamometer (μ-Tas F1) and activity monitor (ActivPAL) in 89 and 26 patients, respectively. Factors associated with postoperative satisfaction, Oxford hip score-activities of daily living, and University of California Los Angeles activity score were identified. The relationship between the Oxford hip score-activities of daily living and daily step counts was examined. [Results] Overall, 94.7% of the patients reported satisfaction with total hip arthroplasty. The Oxford hip score-activities of daily living and University of California Los Angeles activity score were significantly associated with patient satisfaction. Younger age and hip abductor strength were significantly associated with a higher Oxford hip score-activities of daily living and University of California Los Angeles activity score. The average daily step count was significantly correlated with the Oxford hip score-activities of daily living. [Conclusion] Self-reported physical activity levels significantly influenced patient satisfaction and were correlated with objective muscle strength and daily step count measurements. These findings can guide total hip arthroplasty patient counseling on the importance of muscle strength and activity levels.

Opioid-Prescribing Practices Between Total Knee and Hip Arthroplasty in an Outpatient Versus Inpatient Setting

ABSTRACT

Despite trends showing increases in the utilization of outpatient (OP) ambulatory surgery centers (ASCs) and decreases in the utilization of inpatient (IP) facilities for total knee arthroplasty (TKA) and total hip arthroplasty (THA), little is known about opioid prescribing for these procedures between each setting. This study evaluated differences in opioid prescribing and consumption between OP ASC and IP settings for elective TKA and THA surgeries over a 1-year period. Data collection also included pain and satisfaction of pain control postsurgery. In an OP ASC, analysis revealed a significant decrease in pills prescribed (p < .001, p < .001) and consumed (p < .001, p < .001) for TKA and THA, respectively. There was a significant decrease in the morphine equivalence units prescribed (p < .001, p < .001) and consumed (p < .001, p < .001) for TKA and THA, respectively. For TKA, pain was significantly lower (p = .018) and satisfaction of pain control was significantly higher (p = .007). For THA, pain (p = .374) and satisfaction of pain control (p = .173) were similar between the settings. Benefits of performing these surgeries in an OP ASC setting are patients having similar or lower levels of pain and having similar or higher satisfaction of pain control. Patients are also prescribed and consume less opioids. This has important implications for healthcare systems.

Short-term high-dose intravenous iron reduced peri-operative transfusion after staggered bilateral total knee arthroplasty: A retrospective cohort study

BACKGROUND AND OBJECTIVES

Staggered bilateral total knee arthroplasty, two procedures performed 4-7 days apart during a single hospitalization, has an increased risk of blood transfusion. This observational study aimed to evaluate whether immediate post-operative single, high-dose intravenous iron supplementation could reduce transfusion requirements and facilitate anaemia recovery in patients.

MATERIALS AND METHODS

We retrospectively analysed 131 patients who underwent staggered bilateral total knee arthroplasty. The ferric carboxymaltose (FCM) group received 1000 mg of FCM after the first operation. The non-FCM group did not receive intravenous iron. The transfusion rate and post-operative complications were compared between the groups. The anaemia rate was evaluated pre-operatively, during hospitalization, and 5 weeks after the second total knee arthroplasty.

RESULTS

The FCM group comprised 78 patients (59.5%). The rate (21.8% vs. 47.2%, p = 0.004) and amount of transfusion (0 [0-2] vs. 0 [0-0], p = 0.001) was significantly lower in the FCM group than in the non-FCM group. Although both groups' pre-operative haemoglobin concentrations were not significantly different, the FCM group demonstrated higher haemoglobin values 5 weeks post surgery (12.25 ± 0.83 mg/dl vs. 11.48 ± 1.36 mg/dl, p < 0.001). More non-FCM patients developed moderate to severe anaemia at 5 weeks post surgery (p < 0.001). The mortality and complication rates were not significantly different.

CONCLUSIONS

Immediate post-operative, high-dose, intravenous iron treatment may contribute to reduced transfusion rates, facilitate haemoglobin recovery after staggered bilateral total knee arthroplasty, and minimize the development of moderate to severe anaemia.

Surface Roughness of Titanium Orthopedic Implants Alters the Biological Phenotype of Human Mesenchymal Stromal Cells

Metal orthopedic implants are largely biocompatible and generally achieve long-term structural fixation. However, some orthopedic implants may loosen over time even in the absence of infection. In vivo fixation failure is multifactorial, but the fundamental biological defect is cellular dysfunction at the host-implant interface. Strategies to reduce the risk of short- and long-term loosening include surface modifications, implant metal alloy type, and adjuvant substances such as polymethylmethacrylate cement. Surface modifications (e.g., increased surface rugosity) can increase osseointegration and biological ingrowth of orthopedic implants. However, the localized responses of cells to implant surface modifications need to be better characterized. As an in vitro model for investigating cellular responses to metallic orthopedic implants, we cultured mesenchymal stromal/stem cells on clinical-grade titanium disks (Ti6Al4V) that differed in surface roughness as high (porous structured), medium (grit blasted), and low (bead blasted). Topological characterization of clinically relevant titanium (Ti) materials combined with differential mRNA expression analyses (RNA-seq and real-time quantitative polymerase chain reaction) revealed alterations to the biological phenotype of cells cultured on titanium structures that favor early extracellular matrix production and observable responses to oxidative stress and heavy metal stress. These results provide a descriptive model for the interpretation of cellular responses at the interface between native host tissues and three-dimensionally printed modular orthopedic implants, and will guide future studies aimed at increasing the long-term retention of such materials after total joint arthroplasty. Impact statement Using an in vitro model of implant-to-cell interactions by culturing mesenchymal stromal cells (MSCs) on clinically relevant titanium materials of varying topological roughness, we identified mRNA expression patterns consistent with early extracellular matrix (ECM) production and responses to oxidative/heavy metal stress. Implants with high surface roughness may delay the differentiation and ECM formation of MSCs and alter the expression of genes sensitive to reactive oxygen species and protein kinases. In combination with ongoing animal studies, these results will guide future studies aimed at increasing the long-term retention of widely used titanium materials after total joint arthroplasty.

Dual Mobility Cup: Does It Improve Patient's Satisfaction After Total Hip Arthroplasty? A Prospective Comparative Randomized Study

INTRODUCTION

Despite the great success of total hip arthroplasty (THA), many patients were fairly dissatisfied after surgery. Therefore, patient-reported outcome measures have become of an utmost importance in assessing the results after joint replacement. This study was conducted to compare the postoperative patient-reported satisfactions after implantation of two commonly used THA designs.

METHODS

Of 180 patients, who initially fulfilled the study selection criteria and received cementless THA, 165 patients were finally eligible and enrolled in this prospective comparative randomized study. All surgeries were carried out between 2010 and 2018. Two groups of homogenous demographic and clinical data were present. Group A patients (n = 80) were treated by large head THA, whereas group B (n = 85) received dual mobility cup designs. The Western Ontario McMaster Universities Osteoarthritis Index and visual analog scale were used for clinical evaluation. The degree of improvement that the patient expected and hoped before undergoing their surgeries was estimated using the score of the new knee society. The self-administered patient satisfaction scale was used to record the levels of patient satisfaction after surgery, and their values were statistically analyzed in relation to preoperative expectation scores (ie, score of the new knee society) and different clinical and sociodemographic variables.

RESULTS

After a mean follow-up of 79 ± 4.13 months (range 24 to 96 months), both groups recorded a significant improvement (P < 0.05) in Western Ontario McMaster Universities Osteoarthritis Index and visual analogue scale scores. Patients of group B were significantly more satisfied (P < 0.05) than those of group A up to the first postoperative year. Certain studied variables were linked to superior satisfaction results among group B at the last follow-up.

CONCLUSIONS

Dual mobility THA provides better patient satisfaction than their standard large head alternatives specifically among elderly patients, socially unsupported individuals, farmers, heavy manual workers, and those with high levels of expectations.

CLINICAL TRIAL REGISTRATION

Clinical Trials.gov identifier: NCT04333316.

Posterior versus lateral surgical approach: functionality and quality of life after total hip arthroplasty in a matched cohort study

BACKGROUND

One of the most controversial aspects for maximizing outcomes after total hip arthroplasty (THA) remains the surgical approach to the hip joint. The posterior (PA) and lateral approaches (LA) are the two most commonly performed approaches used worldwide, but sparse data are available for their comparison in terms of health-related quality-of-life (HRQoL). The aim of this study was to assess the role of the PA and LA in the HRQoL and hip functionality of patients who underwent primary and elective THA for osteoarthritis, after a minimum 2-year follow-up.

METHODS

One hundred twenty-eight patients (140 THAs: 68 with PA and 72 with LA) were evaluated in a matched cohort study. Data gathered included the body mass index, the American Society of Anesthesiologists score, surgery time, serum creatine phosphokinase (CpK) levels, estimated intraoperative blood loss and intra- or postoperative complications. Preoperatively and at the last follow-up, the activities of daily living, and the instrumental activities of daily living (IADL) scales, the Western Ontario and Mac Master University (WOMAC) Questionnaire, the Harris Hip Score (HHS) and the Visual Analogue Scale (VAS) were used to assess HRQoL and functionality. The Short Form-36 Health Survey (SF-36) Questionnaire was administered at the last follow-up.

RESULTS

Postoperatively, CpK was higher in the LA group compared to the PA (695 ± 648 vs. 447 ± 326 UI/L, p < 0.001). At a mean follow-up of 47 ± 22 months for the LA group and 42 ± 29 months for the PA group, IADL, VAS, HHS and WOMAC scores significantly improved for both groups (all p < 0.001), but PA reported better VAS, residual pain and WOMAC scores (p = 0.002, p = 0.004 and p = 0.018, respectively). The PA group demonstrated a significant higher mental SF-36 subscale values than the LA group (49 ± 13 vs. 42 ± 19, p = 0.001). The LA group showed a higher number of Trendelenburg signs (p = 0.029). On the contrary, the PA group showed a higher number of leg lengthening (p = 0.020); however, most of these cases was less than the clinically significant value of 10 mm (p = 0.738).

CONCLUSIONS

Patients who underwent THA performed with the PA reported greater improvement in HRQoL with lower residual pain, postoperative muscle damage and Trendelenburg signs than those who underwent the LA.

Adverse Effects of Higher Preoperative Pain at Rest, a Central Sensitization-Related Symptom, on Outcomes After Total Hip Arthroplasty in Patients with Osteoarthritis

Background

In patients with hip osteoarthritis (OA), pain at rest, unlike pain on activity, is due to pain mechanisms that cannot be explained by nociceptive pain. However, it remains unclear whether central sensitization (CS) is one of the causes of exacerbated pain at rest in patients with hip OA. Therefore, we investigated the differences in causative factors and postoperative course of total hip arthroplasty (THA) between preoperative pain at rest and on activity in patients with hip OA.

Methods

In total, 120 patients (125 hips, 22 men and 98 women, aged 64.5±1.0 years) with hip OA were included. Preoperative pain at rest and on activity and CS were assessed using the visual analog scale (VAS) and CS Inventory (CSI), respectively. Postoperative assessments were evaluated using the Japanese Orthopedic Association Hip Disease Evaluation Questionnaire (JHEQ); pain, satisfaction, function, and mental scores were evaluated 6 and 12 months after THA.

Results

Multivariate regression analysis indicated the CSI score as affecting VAS for pain at rest (β=0.067, P=0.002) but not VAS for pain on activity (β=0.036, P=0.073). VAS for pain at rest had a weak negative correlation with satisfaction and pain scores at both 6 and 12 months after THA (satisfaction, r=-0.309, -0.278; pain, r=-0.202, -0.22). VAS for pain on activity was not correlated with JHEQ. The CSI score had a weak or moderate negative correlation with three scores other than the function score at both 6 and 12 months after THA (satisfaction, r=-0.266, -0.213; pain, r=-0.332, -0.203, mental, r=-0.427, -0.370). The function score was weakly correlated with the CSI score only 6 months after THA (function, r=-0.231, -0.190).

Conclusion

A higher level of preoperative pain at rest, a CS-related symptom, may affect postoperative pain persistence and dissatisfaction in patients with hip OA.

Effectiveness of patient decision aids for total hip and knee arthroplasty decision-making: a systematic review

OBJECTIVES

To determine the effectiveness of patient decision aids (PtDAs) compared to alternative interventions (including usual care) on decision quality and quality of the decision-making process for adults with hip and knee osteoarthritis considering primary elective total joint arthroplasty.

METHODS

A systematic review guided by Cochrane methods and PRISMA reporting guidelines. Studies were searched in five databases. Included studies were RCTs evaluating the effect of PtDAs on total joint arthroplasty decision-making. Study quality was appraised with Cochrane's risk of bias tool. Quality and strength of recommendations were appraised with GRADE.

RESULTS

Ten included studies were conducted in North American using the same PtDA. Compared to usual care, PtDA groups demonstrated increased decision quality (e.g., higher knowledge, more informed values-based choices) and quality of the decision making process (e.g., decreased decisional conflict) (6 trials). Secondary outcomes showed increased surgeon satisfaction within the consultation and no difference in patient satisfaction or uptake of the chosen option (surgery: RR 1.03, 95% CI = 0.84 to 1.25; I² = 66%; 4 trials). When PtDAs formtats were compared, there were similar effects but no difference between PtDAs (4 trials).

CONCLUSIONS

There was low to very low GRADE certainty of evidence for the effect of PtDAs on decision quality and quality of the decision-making process compared to usual care. No differences were found when different formats of PtDAs were compared (moderate to very low GRADE certainty of evidence).

Evaluation of anteroposterior accelerometric change after bi-cruciate stabilized total knee arthroplasty and posterior stabilized total knee arthroplasty

BACKGROUND

In conventional total knee arthroplasty (TKA), the anterior cruciate ligament (ACL) is resected. ACL dysfunction causes knee instability and is regarded as one factor in poor TKA outcomes. In bi-cruciate stabilized (BCS) TKA, the implant reproduces ACL function and provides anterior stability. The objective of this study was to evaluate preoperative and postoperative X-rays and accelerometer gait measurements in patients who underwent BCS TKA and posterior-stabilized (PS) TKA to assess the postoperative acceleration changes of knees after these procedures and to compare them in terms of joint range of motion (ROM) and the New Knee Society Score (New KSS).

METHODS

The subjects were 60 patients, 30 of whom underwent BCS TKA and 30 PS TKA. Joint ROM, New KSS, lateral X-rays of the standing extended knee, and accelerometer data were evaluated 12 months postoperatively.

RESULTS

There was no significant difference in joint ROM between the groups. Both had good New KSS results, but the functional activity score was significantly higher after BCS TKA than after PS TKA. X-rays showed a lower posterior offset ratio after BCS TKA than after PS TKA, with anteroposterior positioning closer to that of the normal knee. Accelerometer data showed that postoperative anteroposterior acceleration on the femoral side in the stance phase and swing phase was lower after BCS TKA than after PS TKA.

CONCLUSION

Compared with PS TKA, BCS TKA resulted in a higher functional activity score, closer positioning to that of the normal knee on lateral X-ray, and lower anteroposterior acceleration on the femoral side.

Short-Term Clinical Assessment of Hip Hemi-Arthroplasty in 11 Dogs

OBJECTIVE

 The aim of this study was to assess the short-term clinical outcome in dogs following a hip hemi-arthroplasty for the treatment of primary pathological disorders of the hip and as a salvage procedure following failure of the cup component of a total hip replacement.

MATERIALS AND METHODS

 Medical records of dogs that had a unilateral hip hemi-arthroplasty performed between 2015 and 2020 were reviewed. Data collected included follow-up orthopaedic examinations performed at 0, 2, 8 and 52 weeks postoperatively, pelvic radiography at 0, 8 and 52 weeks postoperatively and an owner questionnaire (Helsinki chronic pain index [HCPI]).

RESULTS

 Eleven unilateral hip hemi-arthroplasty procedures were identified. The median age at time of surgery was 3.6 years (8 months-10 years) and the median follow-up time was 13 months (range: 2 months-3 years). The HCPI for all dogs at follow-up was median 8 ± 7.30 (range: 5-25). Total HCPI was < 12 for 7/10 dogs and ≥ 12 for 3 dogs. Pelvic radiographs at 1 year confirmed osteointergration of the femoral stem implant and no evidence of implant subsidence or progression of osteoarthritis. However, there was some evidence of mild lucency of the acetabular bed around the prosthetic femoral head and mild peri-acetabular sclerosis in four cases.

CONCLUSION

 Hip hemi-arthroplasty provides a clinically acceptable treatment for disabling disease of the coxofemoral joint with 10/11 patients achieving acceptable short-term clinical function. Long-term assessment of the hip hemi-arthroplasty and comparison with total hip replacement is indicated.

Preoperative prognostic nutritional index is useful factor for predicting postoperative delirium after primary total joint arthroplasty

Background

Postoperative delirium (PD), as an acute brain failure, is widely reported as a very common postoperative complication, and it is closely associated with increased morbidity and mortality. Recently, malnutrition is reported as one of the risk factors for PD. The prognostic nutritional index (PNI) is a simple method for nutritional evaluation. However, few studies have discussed the effectiveness of PNI as a nutritional assessment in predicting PD after primary total joint arthroplasty (TJA). The aim of this study is to investigate potential risk factors including PNI for PD following primary TJA.

Methods

A retrospective analysis of 994 patients was performed to identify risk factors associated with PD after primary TJA by using univariate and multivariate analyses. A receiver operating characteristic curve and the area under the curve were applied to evaluate the significant results of the multivariate analysis and the optimal cutoff value (CV).

Results

Postoperatively, sixty-seven patients (67/994, 6.7 %) experienced PD. Univariate analysis demonstrated that operative time, duration of anesthesia, age, hypertension, serum albumin, and PNI differed between the PD and non-PD groups (P < 0.05). Multivariate logistic regression analysis showed that the preoperative PNI (odds ratio [OR]: 0.908; 95 % confidence interval [CI]: 0.840–0.983; CV: 47.05), age of patients (OR: 1.055; 95 % CI: 1.024–1.087; CV: 73.5 years), and hypertension (OR: 1.798; 95 % CI: 1.047–3.086), were independently associated with PD (P < 0.05).

Conclusions

A low preoperative PNI associated with malnutrition was demonstrated to be an independent risk factor for PD following primary TJA. Patients with preoperative low PNI should be cautioned and provided with adequate nutritional intervention to reduce postoperative PD.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-021-04626-6.

Synovial fluid pH sensor for early detection of prosthetic hip infections

We describe an implantable sensor developed to measure synovial fluid pH for noninvasive early detection and monitoring of hip infections using standard-of-care plain radiography. The sensor was made of a pH responsive polyacrylic acid-based hydrogel, which expands at high pH and contracts at low pH. A radiodense tantalum bead and a tungsten wire were embedded in the two ends of the hydrogel in order to monitor the change in length of the hydrogel sensor in response to pH via plain radiography. The effective pKa of the hydrogel-based pH sensor was 5.6 with a sensitivity of 3 mm/pH unit between pH 4 and 8. The sensor showed a linear response and reversibility in the physiologically relevant pH range of pH 6.5 and 7.5 in both buffer and bovine synovial fluid solutions with a 30-minute time constant. The sensor was attached to an explanted prosthetic hip and the pH response determined from the X-ray images by measuring the length between the tantalum bead and the radiopaque wire. Therefore, the developed sensor would enable noninvasive detection and studying of implant hip infection using plain radiography.

Home-based rehabilitation programme compared with traditional physiotherapy for patients at risk of poor outcome after knee arthroplasty: the CORKA randomised controlled trial

OBJECTIVES

To evaluate whether a home-based rehabilitation programme for people assessed as being at risk of a poor outcome after knee arthroplasty offers superior outcomes to traditional outpatient physiotherapy.

DESIGN

A prospective, single-blind, two-arm randomised controlled superiority trial.

SETTING

14 National Health Service physiotherapy departments in the UK.

PARTICIPANTS

621 participants identified at high risk of a poor outcome after knee arthroplasty using a bespoke screening tool.

INTERVENTIONS

A multicomponent home-based rehabilitation programme delivered by rehabilitation assistants with supervision from qualified therapists versus usual care outpatient physiotherapy.

MAIN OUTCOME MEASURES

The primary outcome was the Late-Life Function and Disability Instrument (LLFDI) at 12 months. Secondary outcomes were the Oxford Knee Score (a disease-specific measure of function), Knee injury and Osteoarthritis Outcome Score Quality of Life subscale, Physical Activity Scale for the Elderly, 5 dimension, 5 level version of Euroqol (EQ-5D-5L) and physical function assessed using the Figure of 8 Walk test, 30 s Chair Stand Test and Single Leg Stance.

RESULTS

621 participants were randomised between March 2015 and January 2018. 309 were assigned to CORKA (Community Rehabilitation after Knee Arthroplasty) home-based rehabilitation, receiving a median five treatment sessions (IQR 4-7). 312 were assigned to usual care, receiving a median 4 sessions (IQR 2-6). The primary outcome, LLFDI function total score at 12 months, was collected for 279 participants (89%) in the home-based CORKA group and 287 participants (92%) in the usual care group. No clinically or statistically significant difference was found between the groups (intention-to-treat adjusted difference=0.49 points; 95% CI -0.89 to 1.88; p=0.48). There were no statistically significant differences between the groups on any of the patient-reported or physical secondary outcome measures at 6 or 12 months.There were 18 participants in the intervention group reporting a serious adverse event (5.8%), only one directly related to the intervention, all other adverse events recorded throughout the trial related to underlying chronic medical conditions.

CONCLUSIONS

The CORKA intervention was not superior to usual care. The trial detected no significant differences, clinical or statistical, between the two groups on either primary or secondary outcomes. CORKA offers an evaluation of an intervention utilising a different service delivery model for this patient group.

TRIAL REGISTRATION NUMBER

ISRCTN13517704.

Utilisation of outpatient physiotherapy in patients following total knee arthroplasty - a systematic review

OBJECTIVE

Data on the utilisation of outpatient physiotherapy (PT) in patients following total knee arthroplasty (TKA) are scarce, and available studies have not been systematically synthesised. This study aims to summarise the existing literature on outpatient PT following TKA as well as to identify factors associated with its use.

METHODS

A systematic literature search in MEDLINE (via PubMed), CINAHL, Scopus and PEDro was conducted in July 2020 without language restrictions. Two authors independently selected studies, extracted data and assessed study quality. The primary outcome was the proportion being treated with at least one session of outpatient PT (land- or water-based treatments supervised/provided by a qualified physiotherapist) during any defined period within 12 months following TKA. Furthermore, predictors for the use of PT were assessed. Studies including only revision surgeries or bilateral TKA were excluded.

RESULTS

After screening 1934 titles/abstracts and 56 full text articles, 5 studies were included. Proportions of PT utilisation ranged from 16.7 to 84.5%. There were large variations in the time periods after hospital discharge (4 weeks to 12 months) and in the reporting of PT definitions. Female sex was associated with higher PT utilisation, and compared to patients after total hip arthroplasty, utilisation was higher among those following TKA.

CONCLUSION

Despite using a broad search strategy, we found only 5 studies assessing the utilisation of PT after hospital discharge in patients with TKA. These studies showed large heterogeneity in PT utilisation, assessed time periods and PT definitions. Clearly, more studies from different countries with uniform PT definitions are needed to address this relevant public health question.

Predicting dissatisfaction following total hip arthroplasty using a Bayesian model averaging approach: Results from the Australian Arthroplasty Clinical Outcomes Registry National (ACORN)

BACKGROUND

Total hip arthroplasty (THA) provides excellent pain relief and improved function in patients with painful arthritis. The aim of this study was to identify rates and predictors of dissatisfaction following THA.

METHODS

Data were collected prospectively from the Australian Arthroplasty Clinical Outcomes Registry National (ACORN) database between 2014 and 2016 from 2096 patients who underwent THA. Data included baseline demographics, patient-reported outcome measures (PROMs) and postoperative clinical outcomes. Patients were dichotomized into two groups based on their 6-month response to the satisfaction question answered on a Likert scale. Eighteen predefined variables were analyzed. PROMs included full Oxford Hip Score, EQ-5D, and patient satisfaction. A Bayesian model averaging approach was used to build the best predictive model for dissatisfaction. Multiple logistic regression techniques were applied to quantify the effect size of the best model.

RESULTS

At 6 months following THA, 95.4% of patients (n = 2000) were satisfied with surgical outcome and 4.6% (n = 96) were dissatisfied. The only variable that was significantly associated with dissatisfaction after THA was "complications after discharge." This result was consistent for both the complete and imputed dataset (odds ratio 4.78, 95% confidence interval 2.60-8.80, P < 0.001 and odds ratio 3.8, 95% confidence interval 2.60-5.60, P < 0.001, respectively).

CONCLUSION

Our study confirms the high rates of patient satisfaction following THA, with postoperative complications being the only determinant of dissatisfaction. Optimization of patients prior to surgery, reducing postoperative complications, may further improve satisfaction rates after THA.

Patient Factors That Matter in Predicting Hip Arthroplasty Outcomes: A Machine-Learning Approach

BACKGROUND

Despite the success of total hip arthroplasty (THA), approximately 10%-15% of patients will be dissatisfied with their outcome. Identifying patients at risk of not achieving meaningful gains postoperatively is critical to pre-surgical counseling and clinical decision support. Machine learning has shown promise in creating predictive models. This study used a machine-learning model to identify patient-specific variables that predict the postoperative functional outcome in THA.

METHODS

A prospective longitudinal cohort of 160 consecutive patients undergoing total hip replacement for the treatment of degenerative arthritis completed self-reported measures preoperatively and at 3 months postoperatively. Using four types of independent variables (patient demographics, patient-reported health, cognitive appraisal processes and surgical approach), a machine-learning model utilizing Least Absolute Shrinkage Selection Operator (LASSO) was constructed to predict postoperative Hip Disability and Osteoarthritis Outcome Score (HOOS) at 3 months.

RESULTS

The most predictive independent variables of postoperative HOOS were cognitive appraisal processes. Variables that predicted a worse HOOS consisted of frequent thoughts of work (β = -0.34), frequent comparison to healthier peers (β = -0.26), increased body mass index (β = -0.17), increased medical comorbidities (β = -0.19), and the anterior surgical approach (β = -0.15). Variables that predicted a better HOOS consisted of employment at the time of surgery (β = 0.17), and thoughts related to family interaction (β = 0.12), trying not to complain (β = 0.13), and helping others (β = 0.22).

CONCLUSIONS

This clinical prediction model in THA revealed that the factors most predictive of outcome were cognitive appraisal processes, demonstrating their importance to outcome-based research.

LEVEL OF EVIDENCE

Prognostic Level 1.

A Randomized Controlled Trial to Compare Analgesia and Functional Improvement After Continuous Neuroablative and Pulsed Neuromodulative Radiofrequency Treatment of the Genicular Nerves in Patients with Knee Osteoarthritis up to One Year After the Intervention

OBJECTIVES

To compare the analgesic and functional outcomes of continuous neuroablative radiofrequency (CNARF) and pulsed neuromodulative radiofrequency (PNMRF) treatment of genicular nerves up to 1 year after the intervention and to identify predictors associated with a successful outcome (defined as an at least 50% reduction in the pre-interventional visual analog scale [VAS] rating) after genicular radiofrequency treatment.

DESIGN

A prospective randomized controlled trial.

SETTING

The Pain Department of the Jerez de la Frontera University Hospital, Cadíz, Spain, from January 2018 until May 2019.

SUBJECTS

Patients with grade 3-4 gonarthritis suffering from knee pain, with a VAS score ≥5 for >6 months.

METHODS

Eligible participants were randomly assigned to receive either CNARF or PNMRF of the superior medial, superior lateral, and inferior medial genicular nerves. The VAS and Western Ontario and McMaster Universities Osteoarthritis (WOMAC) scores were assessed before and at 1, 6, and 12 months after treatment. Medication use was quantified before and at 6 months after the intervention. Potential characteristics associated with the efficacy of radiofrequency intervention were explored by using multivariable statistical models.

RESULTS

A total of 188 participants were included. The magnitude and duration of beneficial effect and reduction in analgesic use were significantly greater in the CNARF group. Success at 6 months after radiofrequency treatment decreased with grade 4 gonarthritis; higher pre-interventional VAS score; and concomitant depression, anxiety disorder, and diabetes mellitus.

CONCLUSIONS

Therapeutic efficacy and reduction in analgesic consumption were superior after CNARF. Treatment success at 6 months after radiofrequency intervention decreased with more severe gonarthritis; higher pre-interventional pain intensity; and concomitant depression, anxiety disorder, and diabetes mellitus.