Changes in Patient Satisfaction Following Total Joint Arthroplasty

A clinical risk score enables early prediction of dissatisfaction 1 year after total knee arthroplasty

PURPOSE

Dissatisfaction after total knee arthroplasty (TKA) is a prevalent and clinically relevant problem that affects approximately 10%-20% of patients. The aim of this study is to identify factors associated with dissatisfaction 1 year after TKA.

METHODS

A total of 236 patients undergoing TKA were included in this prospective cohort study. Demographic data, preoperative clinical parameters (e.g., axial alignment, osteoarthritis severity) and patient-reported outcome measures (PROMs) were collected preoperatively, at 1 month and 1 year after TKA, encompassing the Knee Society Score (KSS) and Knee injury and Osteoarthritis Outcome Score (KOOS). The primary outcome was dissatisfaction 1 year after TKA, defined as ≤20 points on the KSS satisfaction scale. A risk score based on multiple regression and area under the curve (AUC) analyses was calculated to predict dissatisfaction.

RESULTS

One year after TKA, 16% of the patients were dissatisfied. Dissatisfied patients were significantly younger (p = 0.023) and had a higher body mass index (BMI) (p = 0.007). No differences were observed in preoperative objective (p = 0.903) and functional KSS (p = 0.346), pain (p = 0.306), osteoarthritis severity (p = 0.358), axial knee alignment (p = 0.984) or psychological distress (p = 0.138). The likelihood of dissatisfaction at 1 year was 3.0, 4.0, 7.4, 4.3 and 2.8 times higher amongst patients aged <63.5 years, with a BMI > 30.1 kg/m2, a KOOSPain < 50%, a KSSFunction < 42 points and a KSSExpectation < 9 points (all at 1 month), respectively. Using these variables, a risk score with a maximum of 7 points was developed, demonstrating a high predictive value for dissatisfaction (AUC: 0.792 [95% confidence interval: 0.700-0.884], p < 0.001).

CONCLUSION

Dissatisfaction 1 year after TKA can be predicted by a weighted risk score that includes patient age, BMI, pain, subjective functionality and unmet expectation 1 month postoperatively. Using the risk score, early detection of dissatisfaction has the potential to enable targeted interventions and improve patients' quality of life.

LEVEL OF EVIDENCE

Level II, Prognostic study.

High Expectations Among Patients Who Have Undergone TKA Do Not Correlate With Satisfaction

BACKGROUND

One of five patients is dissatisfied with the outcome of TKA. With the increasing number of TKAs, this affects many patients. It has been suggested that high expectations may influence satisfaction, but the relationship between preoperative patient expectations and postoperative patient satisfaction remains poorly understood.

QUESTIONS/PURPOSES

(1) Are preoperative patient expectations correlated with postoperative satisfaction? (2) Are expectations correlated with patient characteristics or patient-reported outcome measures (PROMs)? (3) Is satisfaction correlated with patient characteristics or PROMs? (4) Do patients report specific items as more relevant to their expectations?

METHODS

This was a single-center, observational, retrospective, comparative study involving patients who underwent TKA. Between December 2020 and June 2022, three senior surgeons performed 306 TKAs. Of these, 76% (234) had the preoperative PROMs required for this study, and of these, 82% (193) had completed PROMs at the 12-month follow-up interval and were analyzed. Of the 193 included patients, 53% (102) were women; the mean age was 68 ± 9 years. Data were collected at baseline, 4 months, and 12 months. Twelve months of follow-up has been shown to be adequate in studies with PROMs. Patient expectations were measured using the validated Hospital for Special Surgery Knee Replacement Expectation Survey on a scale from 0 to 100, with higher scores indicating higher expectations. We also assessed patient satisfaction, the Knee injury and Osteoarthritis Outcome Score, Forgotten Joint Score, High-Activity Arthroplasty Score, EQ-5D-3L, and the objective Knee Society Score. Bivariate linear correlations were analyzed using the Pearson or Spearman test.

RESULTS

Preoperative patient expectations did not correlate with postoperative satisfaction. The mean Hospital for Special Surgery Knee Replacement Expectation Survey score was 82 ±16 points and did not correlate with satisfaction at either 4 months (r = -0.061; p = 0.42) or 12 months (r = -0.126; p = 0.11). Expectations did not correlate with patient characteristics or any of the preoperative or postoperative PROMs or the Knee Society Score. Patient satisfaction was 88% (158 of 179) at 4 months and 83% (160 of 193) at 12 months and did not correlate with patient characteristics or any of the preoperative PROMs or Knee Society Score. Patient satisfaction was medium to strongly correlated with postoperative PROMs and Knee Society Score. The Hospital for Special Surgery Knee Replacement Expectation Survey items with the most frequent expected improvement were "ability to walk" (99% [192 of 193]), "go downstairs" (99% [191 of 192]), and "go upstairs" (99% [192 of 193]).

CONCLUSION

Preoperative expectations were not correlated with postoperative satisfaction or PROMs. Surgeons should be aware that patients have high expectations. However, these expectations appear to be less relevant in determining postoperative satisfaction.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Who Benefits From Hip Arthroplasty or Knee Arthroplasty? Preoperative Patient-reported Outcome Thresholds Predict Meaningful Improvement

BACKGROUND

Hip arthroplasty (HA) and knee arthroplasty (KA) are high-volume procedures. However, there is a debate about the quality of indication; that is, whether surgery is truly indicated in all patients. Patient-reported outcome measures (PROMs) may be used to determine preoperative thresholds to differentiate patients who will likely benefit from surgery from those who will not.

QUESTIONS/PURPOSES

(1) What were the minimum clinically important differences (MCIDs) for three commonly used PROMs in a large population of patients undergoing HA or KA treated in a general orthopaedic practice? (2) Do patients who reach the MCID differ in important ways from those who do not? (3) What preoperative PROM score thresholds best distinguish patients who achieve a meaningful improvement 12 months postsurgery from those who do not? (4) Do patients with preoperative PROM scores below thresholds still experience gains after surgery?

METHODS

Between October 1, 2019, and December 31, 2020, 4182 patients undergoing HA and 3645 patients undergoing KA agreed to be part of the PROMoting Quality study and were hence included by study nurses in one of nine participating German hospitals. From a selected group of 1843 patients with HA and 1546 with KA, we derived MCIDs using the anchor-based change difference method to determine meaningful improvements. Second, we estimated which preoperative PROM score thresholds best distinguish patients who achieve an MCID from those who do not, using the preoperative PROM scores that maximized the Youden index. PROMs were Hip Disability and Osteoarthritis Outcome Score-Physical Function short form (HOOS-PS) (scored 0 to 100 points; lower indicates better health), Knee Injury and Osteoarthritis Outcome Score-Physical Function short form (KOOS-PS) (scored 0 to 100 points; lower indicates better health), EuroQol 5-Dimension 5-level (EQ-5D-5L) (scored -0.661 to 1 points; higher indicates better health), and a 10-point VAS for pain (perceived pain in the joint under consideration for surgery within the past 7 days) (scored 0 to 10 points; lower indicates better health). The performance of derived thresholds is reported using the Youden index, sensitivity, specificity, F1 score, geometric mean as a measure of central tendency, and area under the receiver operating characteristic curve.

RESULTS

MCIDs for the EQ-5D-5L were 0.2 for HA and 0.2 for KA, with a maximum of 1 point, where higher values represented better health-related quality of life. For the pain scale, they were -0.9 for HA and -0.7 for KA, of 10 points (maximum), where lower scores represent lower pain. For the HOOS-PS, the MCID was -10, and for the KOOS-PS it was -5 of 100 points, where lower scores represent better functioning. Patients who reached the MCID differed from patients who did not reach the MCID with respect to baseline PROM scores across the evaluated PROMs and for both HA and KA. Patients who reached an MCID versus those who did not also differed regarding other aspects including education and comorbidities, but this was not consistent across PROMs and arthroplasty type. Preoperative PROM score thresholds for HA were 0.7 for EQ-5D-5L (Youden index: 0.55), 42 for HOOS-PS (Youden index: 0.27), and 3.5 for the pain scale (Youden index: 0.47). For KA, the thresholds were 0.6 for EQ-5D-5L (Youden index: 0.57), 39 for KOOS-PS (Youden index: 0.25), and 6.5 for the pain scale (Youden index: 0.40). A higher Youden index for EQ-5D-5L than for the other PROMs indicates that the thresholds for EQ-5D-5L were better for distinguishing patients who reached a meaningful improvement from those who did not. Patients who did not reach the thresholds could still achieve MCIDs, especially for functionality and the pain scale.

CONCLUSION

We found that patients who experienced meaningful improvements (MCIDs) mainly differed from those who did not regarding their preoperative PROM scores. We further identified that patients undergoing HA or KA with a score above 0.7 or 0.6, respectively, on the EQ-5D-5L, below 42 or 39 on the HOOS-PS or KOOS-PS, or below 3.5 or 6.5 on a 10-point joint-specific pain scale presurgery had no meaningful benefit from surgery. The thresholds can support clinical decision-making. For example, when thresholds indicate that a meaningful improvement is not likely to be achieved after surgery, other treatment options may be prioritized. Although the thresholds can be used as support, patient preferences and medical expertise must supplement the decision. Future studies might evaluate the utility of using these thresholds in practice, examine how different thresholds can be combined as a multidimensional decision tool, and derive presurgery thresholds based on additional PROMs used in practice.

CLINICAL RELEVANCE

Preoperative PROM score thresholds in this study will support clinicians in decision-making through objective measures that can improve the quality of the recommendation for surgery.

One-Year Postoperative Patient-Reported Outcome Measures Are Associated With Three-Year to Five-Year Postoperative Satisfaction in Total Knee Arthroplasty

BACKGROUND

Over the past couple of decades, the definition of success after total knee arthroplasty (TKA) has shifted away from clinician-rated metrics and toward the patient's subjective experience. Therefore, understanding the aspects of patient recovery that drive 3-year to 5-year satisfaction after TKA is crucial. The aims of this study were to (1) determine the 1-year postoperative factors, specifically patient-reported outcome measures (PROMs) that were associated with 3-year and 5-year postoperative satisfaction and (2) understand the factors that drive those who are not satisfied at 1 year postoperatively to become satisfied later in the postoperative course.

METHODS

This was a retrospective study of 402 TKA patients who were gathered prospectively and presented for their 1-year follow-up. Demographics were collected preoperatively and patient-reported outcomes were collected at 1, 3, and 5 years postoperatively. Logistic regressions were used to identify the factors at 1 year that were associated with 3-year and 5-year satisfaction.

RESULTS

Associations between 1-year PROMs with 3-year satisfaction were observed. Longer term satisfaction at 5 years was more closely associated with EuroQol 5 Dimension Mobility, Activity Score, and Numerical Rating Scale Satisfaction. Of those who were not satisfied at 1 year, EuroQol 5 Dimension Mobility, Knee Disability Osteoarthritis Outcome Score Function in Sport and Recreation, and Satisfaction were associated with becoming satisfied at 3 years.

CONCLUSION

The 1-year PROMs were found to be associated with satisfaction at 3 to 5 years after TKA. Importantly, many of the PROMs that were associated with 3-year to 5-year satisfaction, especially in those who were not originally satisfied at 1 year, were focused on mobility and activity level.

Robotic-assisted TKA is Not Associated With Decreased Odds of Early Revision: An Analysis of the American Joint Replacement Registry

BACKGROUND

Robotic-assisted TKA continues to see wider clinical use, despite limited knowledge of its impact on patient satisfaction and implant survival. Most studies to date have presented small cohorts and came from single-surgeon or single-center experiences. Therefore, a population-level comparison of revision rates between robotic-assisted and conventional TKA in the registry setting may help arthroplasty surgeons better define whether robotic assistance provides a meaningful advantage compared with the conventional technique.

QUESTIONS/PURPOSES

(1) After controlling for confounding variables, such as surgeon, location of surgery, and patient comorbidity profile, were robotic-assisted TKAs less likely than conventional TKAs to result in revision for any reason at 2 years? (2) After again controlling for confounding variables, were robotic-assisted TKAs less likely to result in any specific reasons for revision than the conventional technique at 2 years?

METHODS

The American Joint Replacement Registry was used to identify patients 65 years or older who underwent TKA between January 2017 and March 2020 with a minimum of 2 years of follow-up. Patients were limited to age 65 yeas or older to link TKAs to Medicare claims data. Two retrospective cohorts were created: robotic-assisted TKA and conventional TKA. Patient demographic variables included in the analysis were age, gender, BMI, and race. Additional characteristics included the Charlson comorbidity index, anesthesia type, year of the index procedure, and length of stay. A total of 10% (14,216 of 142,550) of TKAs performed during this study period used robotics. Patients with robotic-assisted TKA and those with conventional TKA were similar regarding age (73 ± 6 years versus 73 ± 6 years; p = 0.31) and gender (62% [8736 of 14,126] versus 62% [79,399 of 128,334] women; p = 0.34). A multivariable, mixed-effects logistic regression model was created to analyze the odds of all-cause revision as a factor of robot use, and a logistic regression model was created to investigate specific revision diagnoses.

RESULTS

After controlling for potentially confounding variables, such as surgeon, location of surgery, and Charlson comorbidity index, we found no difference between the robotic-assisted and conventional TKAs in terms of the odds of revision at 2 years (OR of robotic-assisted versus conventional TKA 1.0 [95% CI 0.8 to 1.3]; p = 0.92). The reasons for revision of robotic-assisted TKA did not differ from those of conventional TKA, except for an increased odds of instability (OR 1.6 [95% CI 1.0 to 2.4]; p = 0.04) and pain (OR 2.1 [95% CI 1.4 to 3.0]; p < 0.001) in the robotic-assisted cohort.

CONCLUSION

In light of these findings, surgeons should not assume that robotic assistance in TKA will lead to improved early implant survival. Our findings do not support an improvement over conventional TKA with robotic assistance with regards to common causes of early revisions such malalignment, malposition, stiffness, pain, and instability, and in some cases, suggest there is a benefit to conventional TKA. Differences in the mid-term and long-term revision risk with conventional versus robotic-assisted TKA remain unknown. Appropriate informed consent around the use of robotic assistance should not imply decreased early revision risk.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Oxford Hip Scores, Floor-Sitting Score Trajectories, and Postoperative Satisfaction Rates at 10 Years After Primary Total Hip Arthroplasty

BACKGROUND

Available evidence on outcomes at 5 years and beyond for total hip arthroplasty (THA) is mainly limited to patient-reported outcome measures (PROMs). This study documented the trajectory of functional measurement using the Oxford hip score (OHS) and floor-sitting posture in Japan for up to 10 years post-THA and investigated predictors of dissatisfaction at 10 years with THA.

METHODS

Patients scheduled for primary THA at a university hospital in Japan between 2003 and 2006 were enrolled in this prospective study. Overall, 826 preoperative participants were eligible for follow-up, with response rates ranging from 93.6% to 69.4% at each postoperative survey point. The OHS and floor-sitting scores were calculated using a self-administered questionnaire 6 times up to 10 years postoperatively. Patient satisfaction, including general surgery, walking ability, and activities of daily living (ADL), was assessed in the 10-year survey.

RESULTS

The linear mixed-effects model demonstrated a postoperative improvement, peaking at 7 years for OHS and 5 years earlier for the floor-sitting score. The postoperative overall surgical dissatisfaction at 10 years with THA was very low (3.2%). No predictors of surgical dissatisfaction were identified in the logistic regression analyses. Predictors of walking ability dissatisfaction were older age, men, and worse OHS at 1 year postoperatively. Predictors of ADL dissatisfaction were poorer preoperative and 1-year postoperative floor-sitting scores and 1-year postoperative OHS.

CONCLUSION

The floor-sitting score is a simple PROM suitable for the Japanese population; other populations would require a scale suitable for their lifestyles.

Satisfaction after total knee arthroplasty: a prospective matched-pair analysis of patients with customised individually made and off-the-shelf implants

PURPOSE

Customised individually made (CIM) total knee arthroplasty (TKA) was introduced to potentially improve patient satisfaction and other patient-reported outcome measures (PROMs). The purpose of this study was to compare PROMs, especially patient satisfaction, of patients with CIM and OTS TKA in a matched-pair analysis with a 2-year follow-up.

METHODS

This is a prospective cohort study with a propensity score matching of 85 CIM and 85 off-the-shelf (OTS) TKA. Follow-up was at 4 months, 1 year and 2 years. The primary outcome was patient satisfaction. Secondary outcomes were as follows: overall improvement, willingness to undergo the surgery again, Knee injury and Osteoarthritis Outcome Score (KOOS), Forgotten Joint Score (FJS-12), High-Activity Arthroplasty Score (HAAS), EQ-5D-3L, EQ-VAS, Knee Society Score (KSS) and surgeon satisfaction.

RESULTS

Patient satisfaction ranged from 86 to 90% and did not differ between CIM and OTS TKA. The EQ-VAS after 4 months and the HAAS after 1 year and 2 years were higher for CIM TKA. KOOS, FJS-12 and EQ-5D-3L were not different at follow-up. The changes in KOOS symptoms, pain and daily living were higher for OTS TKA. The KSS was higher for patients with CIM TKA. Surgeon satisfaction was high throughout both groups. Patients who were satisfied after 2 years did not differ preoperatively from those who were not satisfied. Postoperatively, all PROMs were better for satisfied patients. Patient satisfaction was not correlated with patient characteristics, implant or preoperative PROMs, and medium to strongly correlated with postoperative PROMs.

CONCLUSION

Patient satisfaction was high with no differences between patients with CIM and OTS TKA. Both implant systems improved function, pain and health-related quality of life. Patients with CIM TKA showed superior results in demanding activities as measured by the HAAS.

LEVEL OF EVIDENCE

II, prospective cohort study.

Marginalization Influences Access, Outcomes, and Discharge Destination Following Total Joint Arthroplasty in Canada's Universal Healthcare System

BACKGROUND

The influence of socioeconomic status on outcomes following total joint arthroplasty (TJA) in the Canadian single-payer healthcare system is yet to be elucidated. The objective of the present study was to evaluate the impact of socioeconomic status on TJA outcomes.

METHODS

This was a retrospective review of 7,304 consecutive TJA (4,456 knees and 2,848 hips) performed between January 1, 2001 and December 31, 2019. The primary independent variable was the average census marginalization index. The primary dependent variable was functional outcome scores.

RESULTS

The most marginalized patients in both the hip and knee cohorts had significantly worse preoperative and postoperative functional scores. Patients in the most marginalized quintile (V) showed a decreased odds of achieving a minimal important difference in functional scores at 1-year follow-up (odds ratio [OR] 0.44; 95% confidence interval [CI] [0.20, 0.97], P = .043). Patients in the knee cohort in the most marginalized quintiles (IV and V) had increased odds of being discharged to an inpatient facility with an OR of 2.07 (95% CI [1.06, 4.04], P = .033) and OR of 2.57 (95% CI [1.26, 5.22], P = .009), respectively. Patients in the hip cohort in V quintile (most marginalized) had increased odds of being discharged to an inpatient facility with an OR of 2.24 (95% CI [1.02, 4.96], P = .046).

CONCLUSION

Despite being a part of the Canadian universal single-payer healthcare system, the most marginalized patients had worse preoperative and postoperative function, and had increased odds of being discharged to another inpatient facility.

LEVEL OF EVIDENCE

IV.

Assessing ChatGPT Responses to Common Patient Questions Regarding Total Hip Arthroplasty

BACKGROUND

The contemporary patient has access to numerous resources on common orthopaedic procedures before ever presenting for a clinical evaluation. Recently, artificial intelligence (AI)-driven chatbots have become mainstream, allowing patients to engage with interfaces that supply convincing, human-like responses to prompts. ChatGPT (OpenAI), a recently developed AI-based chat technology, is one such application that has garnered rapid growth in popularity. Given the likelihood that patients may soon call on this technology for preoperative education, we sought to determine whether ChatGPT could appropriately answer frequently asked questions regarding total hip arthroplasty (THA).

METHODS

Ten frequently asked questions regarding total hip arthroplasty were posed to the chatbot during a conversation thread, with no follow-up questions or repetition. Each response was analyzed for accuracy with use of an evidence-based approach. Responses were rated as "excellent response not requiring clarification," "satisfactory requiring minimal clarification," "satisfactory requiring moderate clarification," or "unsatisfactory requiring substantial clarification."

RESULTS

Of the responses given by the chatbot, only 1 received an "unsatisfactory" rating; 2 did not require any correction, and the majority required either minimal (4 of 10) or moderate (3 of 10) clarification. Although several responses required nuanced clarification, the chatbot's responses were generally unbiased and evidence-based, even for controversial topics.

CONCLUSIONS

The chatbot effectively provided evidence-based responses to questions commonly asked by patients prior to THA. The chatbot presented information in a way that most patients would be able to understand. This resource may serve as a valuable clinical tool for patient education and understanding prior to orthopaedic consultation in the future.

Systematic lateral retinacular release does not reduce anterior knee pain after total knee arthroplasty with patellar resurfacing

PURPOSE

The aim of this study was to assess the effect of systematic lateral retinacular release (LRR) on anterior knee pain (AKP), as well as its impact on the functional and radiological outcomes after total knee arthroplasty (TKA) with patellar resurfacing.

METHODS

A prospective randomized study was designed. It included patients scheduled for a TKA procedure with patellar resurfacing, who were recruited and randomized into either the LRR group or the non-release group. 198 patients were included in the final analysis. The pressure pain threshold (PPT) assessed by pressure algometry (PA), the visual analogue scale (VAS), Feller's patellar score, the Knee Society Score (KSS), patellar height, and patellar tilt were recorded both preoperatively and at the 1-year follow-up. The Mann-Whitney U test was performed to determine comparisons between both groups as well as to determine differences' intragroup.

RESULTS

Relative to the clinical variables and scores, no difference was detected between the two groups at the 1-year follow-up (p = n.s.). However, there was a slight difference in patellar tilt (0.1º vs. 1.4º, p = 0.044), with higher tilt values in the non-release group. There was no difference in terms of improvement in the clinical and radiological scores and variables recorded between the two groups (p = n.s.).

CONCLUSION

LRR in primary TKA with patellar resurfacing does not show an improvement in AKP and functional outcomes over patellar resurfacing without release.

LEVEL OF EVIDENCE

I.

Predicting whether patients will achieve minimal clinically important differences following hip or knee arthroplasty

Aims

A substantial fraction of patients undergoing knee arthroplasty (KA) or hip arthroplasty (HA) do not achieve an improvement as high as the minimal clinically important difference (MCID), i.e. do not achieve a meaningful improvement. Using three patient-reported outcome measures (PROMs), our aim was: 1) to assess machine learning (ML), the simple pre-surgery PROM score, and logistic-regression (LR)-derived performance in their prediction of whether patients undergoing HA or KA achieve an improvement as high or higher than a calculated MCID; and 2) to test whether ML is able to outperform LR or pre-surgery PROM scores in predictive performance.

Methods

MCIDs were derived using the change difference method in a sample of 1,843 HA and 1,546 KA patients. An artificial neural network, a gradient boosting machine, least absolute shrinkage and selection operator (LASSO) regression, ridge regression, elastic net, random forest, LR, and pre-surgery PROM scores were applied to predict MCID for the following PROMs: EuroQol five-dimension, five-level questionnaire (EQ-5D-5L), EQ visual analogue scale (EQ-VAS), Hip disability and Osteoarthritis Outcome Score-Physical Function Short-form (HOOS-PS), and Knee injury and Osteoarthritis Outcome Score-Physical Function Short-form (KOOS-PS).

Results

Predictive performance of the best models per outcome ranged from 0.71 for HOOS-PS to 0.84 for EQ-VAS (HA sample). ML statistically significantly outperformed LR and pre-surgery PROM scores in two out of six cases.

Conclusion

MCIDs can be predicted with reasonable performance. ML was able to outperform traditional methods, although only in a minority of cases.

Validation of a novel finite-element model for evaluating patellofemoral forces and stress during squatting after posterior-stabilized total knee arthroplasty

INTRODUCTION

Several studies have documented the relationship between patellofemoral pain and patient dissatisfaction after total knee arthroplasty (TKA). However, few computer simulations have been designed to evaluate the patellofemoral joint during flexion. The aim of this study was to validate a new computational simulation, driven by forces and moments, and to analyze patellofemoral reaction forces and stress under squat loading conditions after TKA implantation.

HYPOTHESIS

This computational simulation of a squat using a model driven by forces and moments is comparable to in vitro and in silico data from the literature.

MATERIAL AND METHODS

We developed a finite element model of the lower limb after implantation of a fixed-bearing posterior-stabilized TKA. To simulate squat loading conditions when standing on both legs, an initial load of 130N was applied to the center of the femoral head. Quadriceps force, patellofemoral contact force and Von Mises stress on the patellar implant, tibiofemoral contact forces and pressure on the tibial insert, and post-cam contact force were evaluated from 0° to 100° of knee flexion.

RESULTS

Quadriceps force increased during flexion, up to 6 times the applied load. Von Mises stress on patellar implant increased up to 16MPa at 100° flexion. Tibiofemoral contact forces increased up to 415 N medially and 339 N laterally, with 64% distributed medially on the tibial insert. Post-cam contact started slightly before 70° of flexion.

DISCUSSION

In this simulation, tibiofemoral, patellofemoral and post-cam contact forces, and pressure distribution on the tibial insert were consistent with various published studies. This agreement suggests that computational simulation driven by forces and moments can reproduce squat loading conditions during knee flexion after TKA, without experimental kinematic data used to drive the simulation.

CONCLUSION

This study represents an initial step towards validating tibiofemoral and patellofemoral mechanical behavior under squat conditions, from this computational simulation driven by forces and moments. This model will help us better understand the influence of various implantation techniques on patellofemoral forces and stress during flexion.

LEVEL OF EVIDENCE

IV, biomechanical computational study.

Mechanical complications after total knee arthroplasty

INTRODUCTION

With the increasing demand for total knee arthroplasty (TKA) and the burden of revision TKA on the healthcare system, as well as the quality of life implications for patients, it is extremely important for surgeons to be able to anticipate and prevent TKA mechanical complications. Surgeons must be familiar with the different causes and mechanisms of TKA complications so that they can properly treat patients with failed TKAs and better avoid these complications.

AREAS COVERED

This review addresses TKA mechanical complications and provides context for the topic. A detailed review of surgical factors, implant factors, and patient factors that contribute to mechanical complications after TKA is provided. All of the literature cited in this review was gathered from the PubMed online database using different keywords based on the section of the manuscript.

EXPERT OPINION

As surgeons and engineers solve certain issues in TKA, new challenges will inevitably arise. We must continue to push forward and innovate from both a surgical technique and implant design perspective.

Does Early-Period Patient Dissatisfaction Turn Into Satisfaction Over Time After Total Knee Replacement?

BACKGROUND Total knee arthroplasty (TKA) is frequently used in the treatment of end-stage gonarthrosis, and the patient satisfaction rate varies. This study aimed to reveal the change in mid-term patient satisfaction results and functional scores of patients with low early postoperative satisfaction scores. MATERIAL AND METHODS We included 163 patients who underwent total knee prosthesis between September 2017 and February 2018. Among these patients, early (6 months) and mid-term (24 months) satisfaction and functional results of 34 patients with low satisfaction scores (Likert evaluations 1, 2, and 3) were evaluated. We assessed early-term functional results and satisfaction rates, mid-term analysis of patients who were not satisfied in the early period, and the relationship between functional scores and satisfaction. RESULTS The Likert score was 4 or 5 in 124 (80%) of 158 patients, and early dissatisfaction was detected in 34 patients (20%). In the early-period dissatisfied group, satisfaction scores 6 months after surgery were 1.9±1.1 (1-3) and 4.2±1 (3-5) 24 months after surgery. A statistically significant difference was observed between the dissatisfied group's early and mid-term KSS and KS values. A correlation was observed between satisfaction scores and KS and KSS scores (P<0.05). CONCLUSIONS Patients who do not have mechanical problems with total knee arthroplasty but are not satisfied with the surgery in the early period can be satisfied over time after regular follow-up, appropriate communication and information, and effective rehabilitation.

Association of the Psoas Muscle Index and Sagittal Spinal Alignment With Patient-Reported Outcomes After Total Hip Arthroplasty: A Minimum 5-Year Follow-Up

BACKGROUND

The aim of this study is to assess the association between a spinopelvic malalignment and patient-reported perception of the hip as being "artificial" after total hip arthroplasty (THA). This is a critical issue as an age-related spinopelvic mismatch has been postulated to be associated with the risk of poor outcomes after THA.

METHODS

This is a retrospective case-control study of 274 THAs (244 of whom were women), with a mean follow-up of 6.2 (range 5.0-8.2) years. Hip perception was assessed by asking subjects whether their joint felt "natural" or "artificial." The association between an artificial perception and the following factors was evaluated: age, gender, psoas muscle index (PMI, cross-sectional area of bilateral psoas at L3 divided by height squared), and spinopelvic measures using logistic regression analysis.

RESULTS

An artificial hip perception (130 hips, 47.4%) was associated with a lower PMI (P = .016), Hip Disability and Osteoarthritis Outcome Score Joint Replacement score (P = .035), EuroQol 5-Dimension score (P = .041), and a higher incidence of a pelvic incidence-minus-lumbar lordosis (PI-LL) mismatch >10° (P < .001). A flatback deformity (odds ratio 2.24, 95% confidence interval 1.22-6.31, P = .001) and PMI (odds ratio 0.61, 95% confidence interval 0.34-0.82, P = .012) were predictive of an artificial perception. With the threshold of PI-LL set to 10°, PMI (P = .034), Hip Disability and Osteoarthritis Outcome Score Joint Replacement score (P < .001), joint perception (P = .020), EuroQol 5-Dimension score (P = .028), pain (P = .031), and satisfaction (P < .001) differed between the 2 groups.

CONCLUSION

A flatback deformity is associated with the risk of an artificial perception post-THA, especially in patients with sarcopenia. PMI and PI-LL measurements may help predict THA outcomes.

Functional Outcomes Are Similar After Arthroscopic Capsular Repair of Triangular Fibrocartilage Complex Tears Between Outside-In Technique and All-Inside Technique Using Pre-Tied Suture Device

PURPOSE

To compare outcomes of arthroscopic triangular fibrocartilage complex capsular repair at 2-year follow-up between outside-in and all-inside techniques.

METHODS

In total, 58 consecutive patients (wrists) with a Palmer 1B triangular fibrocartilage complex tear without symptomatic distal radioulnar joint instability underwent arthroscopic suture repair from 2011 to 2019 including 31 patients via the outside-in technique (group A) and 27 via the all-inside technique using a pre-tied needle device (group B). Two-year follow-up included visual analog scale (VAS) pain score, motion range, grip strength, Mayo Modified Wrist Score (MMWS), the Quick Disabilities of the Arm, Shoulder, and Hand (QuickDASH) score, and complication rate. Correlation between functional result and patient satisfaction was analyzed.

RESULTS

Score changes in VAS, wrist flexion-tension, supination-pronation, grip strength, MMWS, and QuickDASH at 2-year follow-up were not significantly different between group A (3.4 ± 0.8, 18.4 ± 17.5, 12.9 ± 13.3, 30.7 ± 11.2, 26.6 ± 7.9 and 19.4 ± 9.9 and group B (3.4 ± 1.0, 18.5 ± 18.3, 15.6 ± 13.7, 30.8 ± 11.4, 28.1 ± 8.6, and 7.6 ± 7.2) with P values of .400, .489, .223, .486, .240, and .223 respectively. Surgical time averaged 105 minutes (78 to 136) in group A and 94 minutes (61-126) in group B with significant difference (P = .012). Patient satisfaction averaged 1.1 (0-3.5) in group A and 1.0 (range 0-3.0) in group B. Satisfaction score was more strongly correlated with QuickDASH (coefficients: 0.863 in group A and 0.918 in group B) than with MMWS (-0.693 in group A and -0.465), grip strength (-0.619 in group A and -0.417 in group B) and VAS score (0.607 in group A and 0.222 in group B).

CONCLUSIONS

Both techniques achieved comparable outcomes with shorter surgical time in all-inside repair using pre-tied needle device. Patient satisfaction was strongly correlated with QuickDASH score.

LEVEL OF EVIDENCE

Level III, retrospective therapeutic comparative investigation.

Mild radiographic osteoarthritis is associated with increased pain and dissatisfaction following total knee arthroplasty when compared with severe osteoarthritis: a systematic review and meta-analysis

PURPOSE

The association between severity of radiographic osteoarthritis with patient pain, function, and satisfaction following total knee arthroplasty has been disputed. The discrepancies in current literature prompt us to further examine this association in a systematic review and meta-analysis.

METHODS

The OVID-Medline, Embase, and Web of Science databases were searched from their inception up to Mar 2020. The main independent variable was osteoarthritis severity as defined by preoperative radiographs. The outcomes measured were pain, function and satisfaction following total knee arthroplasty. A minimum of three studies assessing the same patient-reported outcome measures were included in the meta-analysis, as well as those separating patients by chronic pain or dissatisfaction.

RESULTS

29 studies were included in this study. Significant heterogeneity was seen between radiographic evaluation and reported outcomes. Patients with only mild radiographic osteoarthritis were more likely to suffer from chronic pain (odds ratio = 2.45, 95% CI = 1.80-3.34, p < 0.001) and dissatisfaction (odds ratio = 2.43, 95% CI = 1.79-3.31, p < 0.001) compared to patients with severe osteoarthritis. A significant association was found between mild radiographic severity and lower total Western Ontario and McMaster Universities Osteoarthritis scores (95% CI = - 0.37-0.06, p = 0.006) as well as Knee Society Scores (CI: - 0.54-0.16, p < 0.001).

CONCLUSION

Patients with mild radiographic osteoarthritis are anticipated to gain less from total knee arthroplasty compared to those with severe osteoarthritis. They are also at risk for chronic pain and dissatisfaction and should be consulted about this risk prior to surgery.

LEVEL OF EVIDENCE

III.

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.

Revision total hip arthroplasty is associated with poorer clinically meaningful improvements and patient satisfaction compared to primary total hip arthroplasty

Purpose

This study aims to compare PROM improvements and satisfaction rates between revision (rTHA) and primary total hip arthroplasty (pTHA).

Methods

84 rTHAs were propensity-score matched to 168 pTHAs using patient demographics and preoperative PROMs. Multiple regression was used to evaluate differences in PROMs, minimal clinically important difference (MCID) attainment and patient satisfaction.

Results

Compared to pTHA patients, rTHA patients had poorer MCID attainment for OHS, WOMAC and SF-36 PCS and lower satisfaction rates at 2-years postoperatively (p < 0.05).

Conclusion

Patients undergoing rTHA are likely to have poorer outcomes and should be appropriately counselled to better manage their preoperative expectations.

Level of evidence

Level II.

Preoperative Osteoarthritic Grade Affects Forgotten Joint Status and Patient Acceptable Symptom State After Robotic Arm-Assisted Unicompartmental Knee Arthroplasty

BACKGROUND

This retrospective observational study was designed to investigate the association between radiographic Ahlbäck osteoarthritis (OA) grade and postoperative joint perception in a cohort of patients undergoing medial robotic arm-assisted unicompartmental knee arthroplasty (RA-UKA), using the Forgotten Joint Status and Patient Acceptable Symptom State (PASS) as outcomes.

METHODS

Between January 2014 and May 2019, 660 patients (719 knees) underwent medial RA-UKA at 2 centers. Ahlbäck OA grade was measured on preoperative knee radiographs. Postoperatively, patients were administered the Forgotten Joint Score-12 (FJS-12) and 5-level Likert scale to assess patients' satisfaction. Correlations were described among FJS-12, satisfaction, and Ahlbäck OA grade by means of logistic regression models.

RESULTS

A total of 547 patients (602 knees) were assessed at a mean follow-up of 3.5 years (standard deviation 1.4). A total of 293 cases were graded as Ahlbäck 1 (Group A) and 309 knees were graded as Ahlbäck>1 (Group B). Statistically significant difference was detected in mean FJS-12 (P < .001), but not in the postoperative satisfaction level (P = .06) between the 2 groups. Patients in Group B had a significantly higher probability of attaining a "forgotten knee" after the operation, compared to Group A (P < .05). Cases in Group A had a significantly lower probability of achieving the PASS (P < .01).

CONCLUSION

Patients with higher grades of OA (Ahlbäck>1) were more likely to attain a "forgotten knee," while patients with less severe OA (Ahlbäck 1) were less likely to achieve the PASS after RA-UKA. Although patients with less severe OA reported fairly good outcome, cases in which the results will be poorer are currently difficult to predict.

Patient Satisfaction Following Primary Total Knee Arthroplasty: Contributing Factors

The reported dissatisfaction rate after primary total knee arthroplasty (TKA) ranges between 15% and 25%. The purpose of this article is to perform a narrative review of the literature with the aim of answering the following question: What are the main factors contributing to patient dissatisfaction after TKA? A review of the literature was performed on patient satisfaction after TKA. The search engines used were MedLine (PubMed) and the Cochrane Library. The keywords used were "TKA" and "satisfaction". The main reported preoperative factors positively contributing to patient satisfaction were the following: fulfilment of preoperative expectations, preoperative complete joint space collapse, increasing patellar and lateral compartment osteophyte size, and TKA communication checklist. The principal preoperative factors negatively contributing to patient satisfaction included female sex, comorbidities, and Hispanic race. The chief perioperative factor positively contributing to patient satisfaction was cosmetic closure, whereas the fundamental perioperative factors negatively contributing to patient satisfaction included joint laxity, anterior tibial component slope, and greater femoral component valgus angle. The principal postoperative factors positively contributing to patient satisfaction were the following: ameliorated walking distance, improved range of motion, and improvements in pain. The most important postoperative factors negatively contributing to patient satisfaction included poor postoperative knee stability and soft-tissue balance, functional limitation, surgical complication and reoperation, staff or quality of care issues, and increased stiffness.

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.

Obesity Increases Risk of Failure to Achieve the 1-Year PROMIS PF-10a Minimal Clinically Important Difference Following Total Joint Arthroplasty

INTRODUCTION

The aims of this study were to determine if increasing body mass index (BMI) is a risk factor for failure to attain the 1-year Patient Reported Outcomes Measurement Information System Physical Function (PROMIS PF-10a) minimal clinically important difference (MCID) following total joint arthroplasty (TJA) and to determine a possible BMI threshold beyond which this risk increases significantly.

METHODS

This retrospective study was performed using 3506 TJAs sourced from a regional-based registry. An anchor-based MCID threshold of 7.9 was chosen. PROMIS PF-10a scores were collected at the preoperative and 1-year postoperative timepoints, and the change was used to determine failure to achieve the 1-year MCID. Demographic and surgical variables were also collected. The association between BMI and failure to achieve 1-year PROMIS PF-10 MCID was then evaluated using logistic regression. A BMI threshold was determined using receiver operating characteristic (ROC) curve analysis.

RESULTS

Increasing BMI assessed continuously was a significant risk factor for failure to achieve the MCID (P < .001). "Obese Class I" (30-35 kg/m²), "Obese Class II" (35-40 kg/m²), and "Obese Class III" (>40 kg/m²) subgroups compared to "Normal BMI" (<25 kg/m²) were significantly associated (P < .05) with this adverse outcome as well.

CONCLUSION

Our study showed that increasing BMI is a risk factor for failure to achieve the 1-year PROMIS PF-10a MCID following TJA. Among our patients, an increase in 1 kg/m² increased the risk of failure to achieve the MCID by 2%. With these findings, surgeons will be better equipped to preoperatively advise patients with elevated BMIs considering TJA.

Use of patient-reported outcome measures (PROMs) by orthopedic surgeons in Saudi Arabia

BACKGROUND

There is increasing literature on the usefulness of patient-reported outcome measures (PROMs), but far fewer studies to determine their use by orthopedic surgeons and the barriers they face in applying PROMs in their daily clinical activity.

METHODS

Cross-sectional study using a questionnaire that was distributed in both soft and hard copy formats to a sample of 262 orthopedic surgeons. Participants included orthopedic surgeons who are employed by the Ministry of Health (MOH) in Riyadh and the Eastern Province, Saudi Arabia. The questionnaire was distributed through on-site visitations to orthopedic departments in MOH hospitals as well as through online correspondence by email, WhatsApp, and social media.

RESULTS

The study sample included 262 orthopedic surgeons (13.7% females and 86.3% males). Surgeons aged < 34, 35-44, and 45-54 years old represented 28.66%, 38.9%, and 20.2% of the study sample, respectively. The majority of the included surgeons did not use PROMs (69.1%), and some (17.2%) used it for research purposes. Only 5% used it regularly in daily clinical work.

CONCLUSION

The clinical use of PROMs among orthopedic surgeons was negligible, even though an overwhelming majority were interested in using PROMs. The reasons provided included a lack of knowledge on how to use PROMs and the perception that it is too time-consuming to add to regular clinical routine. There should be more efforts towards training surgeons on how to use PROMs, whereas increasing compatibility with existing software tools used by MOH hospitals may help offset time-related reservations.

Robotic-assisted total knee arthroplasty demonstrates decreased postoperative pain and opioid usage compared to conventional total knee arthroplasty

Aims

Robotic-assisted total knee arthroplasty (RA-TKA) has been introduced to provide accurate bone cuts and help achieve the target knee alignment, along with symmetric gap balancing. The purpose of this study was to determine if any early clinical benefits could be realized following TKA using robotic-assisted technology.

Methods

In all, 140 consecutive patients undergoing RA-TKA and 127 consecutive patients undergoing conventional TKA with minimum six-week follow-up were reviewed. Differences in visual analogue scores (VAS) for pain at rest and with activity, postoperative opiate usage, and length of stay (LOS) between the RA-TKA and conventional TKA groups were compared.

Results

Patients undergoing RA-TKA had lower average VAS pain scores at rest (p = 0.001) and with activity (p = 0.03) at two weeks following the index procedure. At the six-week interval, the RA-TKA group had lower VAS pain scores with rest (p = 0.03) and with activity (p = 0.02), and required 3.2 mg less morphine equivalents per day relative to the conventional group (p < 0.001). At six weeks, a significantly greater number of patients in the RA-TKA group were free of opioid use compared to the conventional TKA group; 70.7% vs 57.0% (p = 0.02). Patients in the RA-TKA group had a shorter LOS; 1.9 days versus 2.3 days (p < 0.001), and also had a greater percentage of patient discharged on postoperative day one; 41.3% vs 20.5% (p < 0.001).

Conclusion

Patients undergoing RA-TKA had lower pain levels at both rest and with activity, required less opioid medication, and had a shorter LOS.

Good long-term outcomes for Direct Anterior Approach Total Hip Arthroplasty in South Africa

This study aims to assess long-term outcomes of Total Hip Arthroplasty (THA) through Direct Anterior Approach (DAA) in a developing country using traditional and novel Patient-Reported Outcomes. There were 522 patients (mean age, 56.5 years; 66.3% female) after mean follow-up 7.35 years. There were 13 revisions. Overall 5-year implant survival rate was 97.5%. Patient Joint Perception scores of 65.5% perceived a completely natural joint. Mean Hip Disability and Osteoarthritis Score was 89.1. Median Forgotten Joint Score-12 was 90 and modified Harris Hip Score was 88. Primary DAA THA in sub-Saharan Africa allows good clinical outcomes at minimum 5 years follow-up.

Outpatients' Satisfaction in the Context of 10 Years of Health-Care Reform: A Cross-Sectional Study of Tertiary Hospitals in Shiyan, China

PURPOSE

This study aimed to evaluate outpatient satisfaction in tertiary hospitals in Shiyan, China, to predict which items had highest priorities for outpatient satisfaction, and to identify population groups on which the medical institutions should focus.

PATIENTS AND METHODS

A cross-sectional survey was conducted at three tertiary hospitals in Shiyan city of China, from March to June 2018. An 18-item outpatient satisfaction questionnaire was applied. We conducted matrix analysis to describe the distribution of satisfaction score and the degree of influence of the items. Outpatient satisfaction was classified into the lowest and highest groups according to the 80/20 rule. Logistic regression model was used to identify demographic factors which might influence outpatient satisfaction.

RESULTS

A total of 2109 valid questionnaires were completed. The "waiting time", "diagnosis and treatment time" and "medical charges" items showed relatively higher degrees of influence but earned lower levels of satisfaction. Outpatients with a college level or above educational background (AOR=1.36, 95% CI=1.03-1.79) and with a family per-capita monthly income (FPMI)>7000 CNY (AOR=3.30, 95% CI=1.60-6.81) were more prevalent in the lowest satisfaction group. Outpatients with college level or above education background (COR=0.77, 95% CI=0.60-0.99), FPMI of 3001-5000 CNY (AOR=0.76, 95% CI=0.60-0.96), non-local residents (AOR=1.48, 95% CI=1.07-2.04), and urban workers with medical insurance (AOR=1.74, 95% CI=1.27-2.39) were more prevalent in the highest satisfaction group.

CONCLUSION

The survey indicated that "long time to wait for treatment", "short treatment time", and "medical charges too expensive" were the top three aspects that need to be improved with priority by medical institutions. Education level, income level, residence and type of health insurance were the sociodemographic characteristics that significantly affect the outpatient satisfaction in tertiary hospitals. These factors need to be paid more attention by healthcare professionals to improve the patients' satisfaction.