Which Preoperative Factors are Associated with Not Attaining Acceptable Levels of Pain and Function After TKA? Findings from an International Multicenter Study

Anxiety and depression prior to total knee arthroplasty are associated with worse pain and subjective function: A prospective comparative study

PURPOSE

The aim of this study was to investigate the influence of preoperative anxiety and depression on subjective function, pain and revision rates following total knee arthroplasty (TKA).

METHODS

A prospective comparative study was conducted, including 349 patients undergoing TKA surgery between January 2019 and April 2021. Patients completed the Hospital Anxiety and Depression Scale (HADS) questionnaire preoperatively, and a set of Patient-Reported Outcome Measures (PROMs) preoperatively and at 6, 12 and 24 months postoperatively. Patients were categorized into anxiety and depression groups based on HADS scores. PROMs included the Knee injury and Osteoarthritis Outcome Score-Physical Function Shortform (KOOS-PS), Oxford Knee Score (OKS) and NRS-Pain. Differences in PROM scores between the anxiety/depression group and, respectively, nonanxiety/nondepression group were assessed, as well as differences in minimal clinical important difference (MCID) and attainment of Patient Acceptable Symptom State (PASS). Lastly, revision rates were compared.

RESULTS

Anxiety and depression groups exhibited inferior subjective function preoperatively and postoperatively compared to nonanxiety and nondepression groups (all p < 0.05), experienced more pain preoperatively (p < 0.001) and also postoperatively for depression patients (all p < 0.05). Significantly fewer patients with anxiety and depression reached the PASS for KOOS-PS, OKS and NRS-Pain (all p < 0.05). There were no differences in the proportion of patients reaching the MCID for all PROMs (all p > 0.060), and revision rates did not differ between groups (both p > 0.96).

CONCLUSION

Preoperative anxiety and depression negatively influence subjective function and pain preoperatively and up to 2-year follow-up in patients undergoing TKA. Revision rates did not differ between groups, and there were no relevant differences in clinical improvement of subjective function and pain.

LEVEL OF EVIDENCE

Level II, prospective comparative study.

Patient Selection in Randomized Controlled Trials of Total Knee Arthroplasty: A Systematic Review Assessing Inclusion Criteria

BACKGROUND

Patients undergo total knee arthroplasty (TKA) at widely disparate stages of osteoarthritis, raising the possibility of high heterogeneity among patients enrolled in TKA research studies. Obscuration of treatment effectiveness and other problems that may stem from cohort heterogeneity can be controlled in clinical studies by rigorously defining target patients. The purpose of this review was to determine the extent to which randomized controlled trials (RCTs) on TKA use osteoarthritis severity, as defined by radiographic grade or patient-reported outcome measures (PROMs), in their inclusion criteria, and to investigate potential impact on outcome.

METHODS

A search of PubMed, Embase, Scopus, Web of Science, and Cochrane databases used a combination of terms involving TKA, PROMs, and radiographic scoring. A total of 1,227 studies were independently reviewed by 2 screeners for the above terms. RCTs with ≥100 patients (236) and with <100 patients (325) undergoing TKA were analyzed with regard to the specific inclusion criteria and recruitment process.

RESULTS

Among the identified RCTs with ≥100 patients, 18 (<8%, with a total of 2,952 randomized patients) used specific radiographic scoring or PROM thresholds in their inclusion criteria. Eleven of the 18 studies used specific radiographic scoring, such as the Kellgren-Lawrence or Ahlbäck classifications. Three studies used preoperative PROM thresholds: Knee Society Knee Score of <60, Knee Society Function Score of <60, Oxford Knee Score of <20, and Hospital for Special Surgery Score of <60. Among studies with <100 patients, 48 (<15%) used specific inclusion criteria.

CONCLUSIONS

The vast majority of RCTs (>85%) did not enroll patients based on disease severity, as measured by PROM score thresholds or radiographic classifications, in their inclusion criteria. The lack of consistent inclusion criteria likely results in heterogeneous cohorts, potentially undermining the validity of RCTs on TKA.

LEVEL OF EVIDENCE

Prognostic Level I . See Instructions for Authors for a complete description of levels of evidence.

Do the Revision Rates of Arthroplasty Surgeons Correlate With Postoperative Patient-reported Outcome Measure Scores? A Study From the Australian Orthopaedic Association National Joint Replacement Registry

BACKGROUND

Patient-reported outcome measures (PROMs) are a pragmatic and efficient means to evaluate the functional quality of arthroplasty beyond revision rates, which are used by most joint replacement registries to judge success. The relationship between these two measures of quality-revision rates and PROMs-is unknown, and not every procedure with a poor functional result is revised. It is logical-although still untested-that higher cumulative revision rates correlate inversely with PROMs for individual surgeons; more revisions are associated with lower PROM scores.

QUESTIONS/PURPOSES

We used data from a large national joint replacement registry to ask: (1) Does a surgeon's early THA cumulative percent revision (CPR) rate and (2) early TKA CPR rate correlate with the postoperative PROMs of patients undergoing primary THA and TKA, respectively, who have not undergone revision?

METHODS

Elective primary THA and TKA procedures in patients with a primary diagnosis of osteoarthritis that were performed between August 2018 and December 2020 and registered in the Australian Orthopaedic Association National Joint Replacement Registry PROMs program were eligible. THAs and TKAs were eligible for inclusion in the primary analysis if 6-month postoperative PROMs were available, the operating surgeon was clearly identified, and the surgeon had performed at least 50 primary THAs or TKAs. Based on the inclusion criteria, 17,668 THAs were performed at eligible sites. We excluded 8878 procedures that were not matched to the PROMs program, leaving 8790 procedures. A further 790 were excluded because they were performed by unknown or ineligible surgeons or were revised, leaving 8000 procedures performed by 235 eligible surgeons, including 4256 (53%; 3744 cases of missing data) patients who had postoperative Oxford Hip Scores and 4242 (53%; 3758 cases of missing data) patients who had a postoperative EQ-VAS score recorded. Complete covariate data were available for 3939 procedures for the Oxford Hip Score and for 3941 procedures for the EQ-VAS. A total of 26,624 TKAs were performed at eligible sites. We excluded 12,685 procedures that were not matched to the PROMs program, leaving 13,939 procedures. A further 920 were excluded because they were performed by unknown or ineligible surgeons, or because they were revisions, leaving 13,019 procedures performed by 276 eligible surgeons, including 6730 (52%; 6289 cases of missing data) patients who had had postoperative Oxford Knee Scores and 6728 (52%; 6291 cases of missing data) patients who had a postoperative EQ-VAS score recorded. Complete covariate data were available for 6228 procedures for the Oxford Knee Score and for 6241 procedures for the EQ-VAS. The Spearman correlation between the operating surgeon's 2-year CPR and 6-month postoperative EQ-VAS Health and Oxford Hip or Oxford Knee Score was evaluated for THA and TKA procedures where a revision had not been performed. Associations between postoperative Oxford and EQ-VAS scores and a surgeon's 2-year CPR were estimated based on multivariate Tobit regressions and a cumulative link model with a probit link, adjusting for patient age, gender, ASA score, BMI category, preoperative PROMs, as well as surgical approach for THA. Missing data were accounted for using multiple imputation, with models assuming they were missing at random and a worst-case scenario.

RESULTS

Of the eligible THA procedures, postoperative Oxford Hip Score and surgeon 2-year CPR were correlated so weakly as to be clinically irrelevant (Spearman correlation ρ = -0.09; p < 0.001), and the correlation with postoperative EQ-VAS was close to zero (ρ = -0.02; p = 0.25). Of the eligible TKA procedures, postoperative Oxford Knee Score and EQ-VAS and surgeon 2-year CPR were correlated so weakly as to be clinically irrelevant (ρ = -0.04; p = 0.004 and ρ = 0.03; p = 0.006, respectively). All models accounting for missing data found the same result.

CONCLUSION

A surgeon's 2-year CPR did not exhibit a clinically relevant correlation with PROMs after THA or TKA, and all surgeons had similar postoperative Oxford scores. PROMs, revision rates, or both may be inaccurate or imperfect indicators of successful arthroplasty. Missing data may limit the findings of this study, although the results were consistent under a variety of different missing data scenarios. Innumerable factors contribute to arthroplasty results, including patient-related variables, differences in implant design, and the technical quality of the procedure. PROMs and revision rates may be analyzing two different facets of function after arthroplasty. Although surgeon variables are associated with revision rates, patient factors may exert a stronger influence on functional outcomes. Future research should identify variables that correlate with functional outcome. Additionally, given the gross level of function that Oxford scores record, outcome measures that can identify clinically meaningful functional differences are required. The use of Oxford scores in national arthroplasty registries may rightfully be questioned.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Intra-operative laxity and balance impact 2-year pain outcomes in TKA: a prospective cohort study

PURPOSE

The objective of this study was to determine if intra-operatively measured joint gaps are associated with 2-year pain outcomes in total knee arthroplasty (TKA) and whether balance and laxity windows could be defined throughout flexion to optimize 2-year pain outcomes. Our hypothesis is that intra-operative joint gaps are associated with 2 year post-operative pain outcome.

METHODS

A prospective study investigating 310 robotically assisted TKAs was performed. Final intra-operative joint gap data were recorded using a digital tensioner and component alignment data were recorded by the robotics system. Patient demographics and Knee Injury and Osteoarthritis Outcome Score (KOOS) were recorded pre-operatively and KOOS and Hospital for Special Surgery (HSS) satisfaction were recorded at 2 years post-op. A random search Simulated Annealing (SANN) optimisation algorithm was used to determine global optimum laxity and balance windows at different flexion angles which maximized the 2-year KOOS pain scores. The windows were combined to determine the impact of achieving optimal laxity and balance throughout flexion. To improve clinical utility, boundaries identified by the SANN algorithm were rounded to the nearest 0.5 mm before statistical analysis.

RESULTS

Laxity and balance windows were defined in extension (Med lax: -2.0 to 2.5 mm, Lat lax: -0.5 to 2.5 mm, Balance: -3.0 to 0.0 mm), mid-flexion (Med lax: -1.0 to 2.5 mm, Lat lax: -0.5 to 3.0 mm, Balance: -2.0 to 2.0 mm), and flexion (Med lax: -2.0 to 3.5 mm, Lat lax: -2.0 to 1.5 mm, Balance: -3.0 to 3.0 mm). When all windows were satisfied, the greatest difference in KOOS pain score was observed (100.0 vs 94.4, p < 0.0001). The highest percentage of knees satisfying the Patient Acceptable Symptom State (PASS) for KOOS pain was also observed in knees which satisfied all windows compared to knees which did not (93% vs 71%, p = 0.0009). The proportion of knees which satisfy the PASS threshold decreased in knees which only satisfied 1-3 (29%) or 4-6 (69%) windows (p ≤ 0.0018). No optimal windows were found between component alignment and KOOS pain outcome (p ≥ 0.1180). High satisfaction was found across all groups (≥ 95%).

CONCLUSION

Intra-operatively measured joint gaps are associated with all KOOS sub-score outcomes at 2 years after TKA. Optimal windows for a clinically relevant improvement in post-operative KOOS pain were defined for laxity and balance but not for alignment indicating balance may have a greater impact on outcome than alignment.

LEVEL OF EVIDENCE

II.

Obese Patients Achieve Good Improvements in Patient-Reported Outcome Measures After Medial Unicompartmental Knee Arthroplasty Despite a Lower Preoperative Score

BACKGROUND

In this study, we examined the association between obesity and patient-reported outcome measures after medial unicompartmental knee arthroplasty (MUKA), assessed through score changes, Patient Acceptable Symptom State (PASS), and minimal important change (MIC). Second, the association between obesity and early readmissions was examined.

METHODS

A total of 450 MUKAs (mean body mass index [BMI] 30.3, range, 19.6-53.1), performed from February 2016 to December 2020, were grouped using BMI: <30, 30-34.9, and >34.9. Oxford Knee Score (OKS), Forgotten Joint Score (FJS), and Activity and Participation Questionnaire (APQ) were assessed preoperatively and at 3, 12, and 24 months, postoperatively. The 12-month PASS and MIC were also assessed, defining PASS as OKS = 30, MIC-OKS as change in OKS = 8, and MIC-FJS as change in FJS = 14.

RESULTS

No significant differences in OKS change were found between BMI groups. After 12 months, patients who had a BMI of 30-34.9 had lower change in FJS (estimate -8.1, 95% CI -14.9 to -1.4) and were less likely to reach PASS (odds ratio 0.4, 95% CI 0.2-0.7) as well as MIC-FJS (odds ratio 0.5, 95% CI 0.2-0.9). Both obese groups had lower change in APQ after 12 months. Differences in 90-day readmission rates were nonsignificant between groups.

CONCLUSION

Our findings of no differences in OKS improvement between BMI groups and achieving MIC for BMI > 34.9 suggest good improvements in obese patients despite lower preoperative scores, supporting contemporary indications for MUKA. Lower APQ development and achievement of 12-month PASS may be used when addressing expectations of recovery.

Should We Aim to Help Patients "Feel Better" or "Feel Good" After Total Hip Arthroplasty? Determining Factors Affecting the Achievement of the Minimal Clinically Important Difference and Patient Acceptable Symptom State

BACKGROUND

Recent attempts have been made to use preoperative patient-reported outcome measure (PROM) thresholds as prior authorization criteria based on the assumption that patients who have higher baseline scores are less likely to achieve the minimal clinically important difference (MCID). This study aimed to identify factors affecting the achievement of MCID and patient acceptable symptom state (PASS) after total hip arthroplasty (THA), and to determine the overlap between the two outcomes.

METHODS

We identified 3,581 primary, unilateral THAs performed at a single practice in 2015-2019. PROMs including Hip Disability and Osteoarthritis Outcome Score for Joint Replacement (HOOS-JR) and 12-item Short Form Health Survey were collected preoperatively and 1-year postoperatively. The likelihood of attaining PASS according to attainment of MCID was assessed. Multivariable regression was used to identify independent predictors of MCID and PASS.

RESULTS

In total, 79.8% achieved MCID and 73.6% achieved PASS for HOOS-JR. Approximately 1 in 7 patients who achieved MCID did not eventually achieve PASS. Worse preoperative HOOS-JR (odd ratio 0.933) was associated with MCID attainment. Better preoperative HOOS-JR (odd ratio 1.015) was associated with PASS attainment. Men, lower body mass index, better American Society of Anesthesiologists score, and better preoperative 12-item Short Form Health Survey mental score were predictors of MCID and PASS. Age, race, ethnicity, Charlson Comorbidity Index, and smoking status were not significant predictors.

CONCLUSION

Preoperative PROMs were associated with achieving MCID and PASS after THA, albeit in opposite directions. Clinicians should strive to help patients "feel better" and "feel good" after surgery. Preoperative PROMs should not solely be used to prioritize access to care.

Higher Dissatisfaction Rate Following Revision Compared With Primary Total Knee Arthroplasty: 1-Year Follow-up of 2151 Primary and 235 Aseptic Revision Surgeries

Postoperative patient satisfaction is related to preoperative expectations. Information regarding expected results following surgery is therefore important. This study evaluated patient-reported outcome measures (PROMs) and patient satisfaction up to 1 year after primary and aseptic revision total knee arthroplasty (TKA). The study included 2151 primary and 235 aseptic revision TKA surgeries conducted between 2010 and 2018. Pain, Knee Injury and Osteoarthritis Outcome Score-Physical Function-Short Form and European Quality of Life-5 Dimension surveys were recorded preoperatively and at 8 weeks and 1 year. To determine satisfaction, patients were asked to rate their knee function compared with that before surgery and to answer whether they would undergo the surgery again given their current knowledge. Patients who had primary TKA improved in all PROMs in each follow-up up to 1 year, whereas patients who had revision TKA showed improvement at 8 weeks with no further improvement at 1 year. In terms of patient satisfaction, 88% of patients in the primary TKA group reported better knee function, and 87% were willing to have the surgery again at 1 year; the proportions were lower for patients who underwent revision TKA (66% and 68%, respectively). Aseptic revision TKA demonstrates inferior PROMs compared with those of primary TKA 1 year after surgery, and more than 30% of the patients who underwent revision TKA stated that they would not have their TKA revised or were uncertain, given the outcome of the procedure. Thus, patients who are candidates for revision TKA should be informed to expect less of an improvement following revision surgery than with the primary TKA. Our findings can facilitate the shared decision-making process by surgeons and patients based on realistic expectations of surgical outcomes. [Orthopedics. 2023;46(1):e52-e57.].

One-Year Readmissions Following Total Joint Arthroplasty May Be Associated With Failure to Achieve the Minimal Clinically Important Difference of Patient-Reported Outcomes Measurement Information System Physical, Mental, and Physical-Short Form-10a

The primary aims of our study were to determine if hospital readmissions within one year following primary total joint arthroplasty (TJA) and their relative timing influence patients' ability to achieve the two-year Patient-Reported Outcomes Measurement Information System (PROMIS) physical, PROMIS mental, and PROMIS Physical-Function-Short-Form-10a (SF-10a) minimal clinically important difference (MCID). This is a retrospective study conducted using data from a multi-institutional, arthroplasty registry. Only patients with paired patient-reported outcome measure (PROM) assessments (preoperatively and two years postoperatively) were included. Five separate readmission cohorts were formed: (1) any-cause readmission within one year, (2) any-cause readmission within 90 days, (3) non-index-surgery-related readmission within 90 days, (4) index-surgery-related readmission within one year, and (5) index-surgery-related readmission within 90 days. A propensity score match was used to match each of the patients to one of the 972 patients (1:1 basis) in the non-readmission group. The association between failure to achieve each of the three two-year MCIDs and Readmission status was analyzed using logistic regression. We found that all readmissions within one year and index-surgery-related readmissions within one year resulted in an increased risk of failure to achieve the two-year MCID across all three collected PROMs. Index surgery-related readmissions within 90 days (OR 3.24; 95% CI 1.05-11.05; p=0.048) sustained significantly different rates of two-year PROMIS physical MCID achievement compared to matched controls. Postoperative complications requiring readmission, particularly those related to the joint arthroplasty and those within 90 days of index surgery, significantly impact the ability to achieve the two-year MCID of PROMs.

Lumbar Spine Sagittal Mismatch Deformity Negatively Affects Total Knee Arthroplasty Outcomes

There is currently a paucity of data regarding the potential relationships between preexisting spinal deformity and clinical outcomes following total knee arthroplasty (TKA). We sought to expand upon this deficit. We hypothesize that lumbar sagittal mismatch deformity (MD) will correlate with a decrease in functional outcomes after TKA. This retrospective cohort comparison of 933 TKAs was performed between January 2017 and 2020. TKAs were excluded if they were not performed for primary osteoarthritis (OA) or if preoperative lumbar radiographs were unavailable/inadequate to measure sagittal parameters of interest: pelvic incidence, sacral slope, pelvic tilt, lumbar lordosis, and deformity mismatch. Ninety-four TKAs were subsequently available for inclusion and divided into two groups: those with MD as defined by |PI-LL| > 10 degrees and those without MD. The following clinical outcomes were compared between the groups: total postoperative arc of motion (AOM), incidence of flexion contracture, and need for manipulation under anesthesia (MUA). In total, 53 TKAs met the MD criteria, while 41 did not have MD. There were no significant differences in demographics, body mass index, preoperative knee range of motion (ROM), preoperative AOM, or opiate use between the groups. TKAs with MD were more likely to have MUA (p = 0.026), ROM <0 to 120 (p < 0.001), a decreased AOM by 16 degrees (p < 0.001), and a flexion contracture postoperatively (p = 0.01). Preexisting MD may adversely affect clinical results following TKA. Statistically and clinically significant decreases in postoperative ROM/AOM, increased likelihood of flexion contracture, and increased need for MUA were all noted in those with MD. This is a Level 3 study.

Isolated Lateral Tibiofemoral Compartment Osteoarthritis: Survivorship and Patient Acceptable Symptom State After Lateral Fixed-Bearing Unicompartmental Knee Arthroplasty at Mean 10-Year Follow-up

BACKGROUND

Lateral unicompartmental knee arthroplasty (UKA) is an excellent option to alleviate disability and restore function in patients with lateral compartment knee osteoarthritis (OA). The purpose of the present study was to determine the survivorship and long-term outcomes in both younger/middle-aged and older patients with lateral compartment OA following non-robotically-assisted, fixed-bearing lateral UKA and to determine if an acceptable symptom state can be achieved.

METHODS

All patients were managed with fixed-bearing lateral UKA by a single surgeon utilizing a lateral parapatellar approach without robotic assistance. The primary outcome variables were the Knee injury and Osteoarthritis Outcome Score (KOOS) Activities of Daily Living (ADL) and Sport subscale scores. In addition, the other KOOS subscores, the Lysholm score, the achievement of the Patient Acceptable Symptom State (PASS), and the Veterans RAND (VR-12) Physical Component Summary score (PCS) and Mental Component Summary score (MCS) were collected. Failure was defined as conversion to total knee arthroplasty (TKA). Patients were divided into 2 cohorts: younger/middle-aged patients (<60 years of age) and older patients (≥60 years of age).

RESULTS

A cohort of 256 patients underwent medial (n = 193) or lateral (n = 63) UKA. Sixty-one patients met the inclusion criteria. At mean of 10 years (range, 4 to 17 years) of follow-up, there were no significant differences between the groups in terms of any patient-reported outcome measures (p > 0.05). The percentage of patients in whom PASS was achieved on the KOOS ADL and Sport subscores was 82% and 88%, respectively, in the younger cohort and 80% and 80%, respectively, in the older cohort. The mean survival estimate of the prothesis was 15.3 years (95% confidence interval [CI], 14.5 to 16.2 years) for the entire cohort. The estimated rate of implant survival in the younger cohort was 100% at 5 and 10 years, and the estimated rate of implant survival in the older cohort was 98% at 5 years and 96% at 10 years.

CONCLUSIONS

Lateral fixed-bearing, non-robotic UKA for the treatment of isolated lateral compartment OA resulted in >80% of patients reaching an acceptable symptom state in terms of both activities of daily living and sporting activities. UKA provides an excellent option that provides longevity with high PASS rates and return to activities with a low risk of complications and failure.

LEVEL OF EVIDENCE

Therapeutic Level III . See Instructions for Authors for a complete description of levels of evidence.

The Paradox of Patient-Reported Outcome Measures: Should We Prioritize "Feeling Better" or "Feeling Good" After Total Knee Arthroplasty?

BACKGROUND

The use of preoperative patient-reported outcome measure (PROM) thresholds for patient selection in arthroplasty care has been questioned recently. This study aimed to identify factors affecting achievement of the minimal clinically important difference (MCID) and patient acceptable symptom state (PASS) after total knee arthroplasty (TKA) and determine the overlap between the two outcomes.

METHODS

We identified 1,239 primary, unilateral TKAs performed at a single institution in 2015-2019. PROMs including the Knee injury and Osteoarthritis Outcome Score for Joint Replacement (KOOS-JR) and 12-item Short Form Health Survey (SF-12) were collected preoperatively and 1-year postoperatively. The likelihood of attaining PASS as per attainment of MCID was assessed. A multivariable regression was used to identify predictors of MCID and PASS.

RESULTS

In total, 71.3% achieved MCID and 75.5% achieved PASS for KOOS-JR. Only 7.7% achieved MCID but not PASS, whereas almost twice this number did not achieve MCID but did achieve PASS (11.9%). Poorer preoperative KOOS-JR (OR 0.925), better SF-12 physical (OR 1.025), and mental (OR 1.027) were associated with MCID attainment. In contrast, better preoperative KOOS-JR (OR 1.030) and SF-12 mental (OR 1.025) were associated with PASS attainment. Age, gender, race, ethnicity, body mass index, Charlson index, American Society of Anesthesiologists classification, and smoking status were not significant predictors.

CONCLUSION

Preoperative PROMs were associated with achieving MCID and PASS after TKA, albeit some positively and some negatively. In the era of value-based care, clinicians should not only strive to help patients "feel better" but also ensure that patients "feel good" after surgery. This study does not support the use of PROMs in prioritizing access to care.

The Lawrence D. Dorr Surgical Techniques & Technologies Award: Patient Acceptable Symptom State (PASS) in Medial and Lateral Unicompartmental Knee Arthroplasty: Does the Status of the ACL Impact Outcomes?

BACKGROUND

The aim of this study is to determine if there is a difference in the percentage of patients who reach Patient Acceptable Symptom State (PASS) when comparing anterior cruciate ligament (ACL)-deficient and ACL-intact knees following fixed-bearing medial and lateral unicompartmental knee arthroplasty (UKA).

METHODS

A consecutive series of 215 knees that underwent UKA (medial = 158, lateral = 57) were included in the study. The Knee Osteoarthritis Outcome Score functional score [KOOS activities of daily living (ADL)] and KOOS Sport were used as the primary outcome variables. A KOOS ADL PASS of 87.5 and KOOS Sport PASS of 43.8 were previously described for total knee arthroplasty (TKA). Failure was defined as conversion to TKA.

RESULTS

There were 157 in the ACL-intact group and 58 in the ACL-deficient group. Conversion to TKA was 3.7%. The failure rate in the ACL-deficient group was 5% (3/58) and 3% (5/157) in the ACL-intact group (P = .447). The mean survival for the entire group was 18.1 years (95% confidence interval 17.6-18.6). At 10 years, the survival was 94.3% (standard error = 0.028) in the ACL-deficient group and 97.6% (standard error = 0.014) in the ACL-intact group. At a mean 10 ± 3.5 years, with 93% follow-up, 83% in the ACL-deficient group and 80% in the ACL-intact group reached PASS for KOOS ADL (P = .218). For KOOS Sport, 85% of the ACL-deficient group compared to 81% in the ACL-intact group (P = .374) reached PASS.

CONCLUSION

The ACL-deficient cohort results were not significantly different compared to ACL-intact knees in both medial and lateral compartment UKA. Fixed-bearing medial and lateral UKA resulted in low failure rate and excellent long-term outcomes.

Factors contributing to 1-year dissatisfaction after total knee arthroplasty: a nomogram prediction model

Background

Identifying risk factors and early intervention are critical for improving the satisfaction rate of total knee arthroplasty (TKA). Our study aimed to identify patient-specific variables and establish a nomogram model to predict dissatisfaction at 1 year after TKA.

Methods

This prospective cohort study involved 208 consecutive primary TKA patients with end-stage arthritis who completed self-reported measures preoperatively and at 1 year postoperatively. All participants were randomized into a training cohort (n = 154) and validation cohort (n = 54). Multiple regression models with preoperative and postoperative factors were used to establish the nomogram model for dissatisfaction at 1 year postoperatively. The least absolute shrinkage and selection operator method was used to screen the suitable and effective risk factors (demographic variables, preoperative variables, surgical variable, and postoperative variables) collected. These variables were compared between the satisfied and dissatisfied groups in the training cohort. The receiver operating characteristic (ROC) curve, calibration plot, and decision curve analysis were used to validate the discrimination, calibration, and clinical usefulness of the model. Results were evaluated by internal validation of the validation cohort.

Results

The overall satisfaction rate 1 year after TKA was 77.8%. The nomogram prediction model included the following risk factors: gender; primary diagnosis; postoperative residual pain; poor postoperative range of motion; wound healing; and the rate of change in the degree of coronal lower limb alignment (hip–knee–ankle angle, HKA).The ROC curves of the training and validation cohorts were 0.9206 (95% confidence interval [CI], 0.8785–0.9627) and 0.9662 (0.9231, 1.0000) (95% CI, 0.9231, 1.0000), respectively. The Hosmer–Lemeshow test showed good calibration of the nomogram (training cohort, p = 0.218; validation cohort, p = 0.103).

Conclusion

This study developed a prediction nomogram model based on partially modifiable risk factors for predicting dissatisfaction 1 year after TKA. This model demonstrated good discriminative capacity for identifying those at greatest risk for dissatisfaction and may help surgeons and patients identify and evaluate the risk factors for dissatisfaction and optimize TKA outcomes.

The duration of postoperative analgesic use after total knee arthroplasty and nomogram for predicting prolonged analgesic use

Background

Total knee arthroplasty is currently a reliable treatment for end-stage knee osteoarthritis. However, chronic postsurgical pain (CPSP) is substantially thought to reduce patient satisfaction. NSAID-based oral analgesics were used to manage CPSP, but research on the duration of postoperative analgesic use (DAU) and prolonged analgesic use (PAU) are presently scarce.

Methods

Preoperative, perioperative, and one-year or above postoperative follow-up data were collected from 162 patients who underwent total knee arthroplasty between 1 June 2018 and 1 March 2019, and the DAU and the discontinuation time of each patient after discharge were recorded. Observational statistical analysis, diagnostic test, and predictive nomogram construction were performed on the collected data.

Results

The 3-month DAU has good diagnostic utility for poor outcome of postoperative months twelve (POM12). The constructed nomogram shows that gender, preoperative Numeric Rating Scale (NRS) movement pain scores, duration of surgery, postoperative days three (POD3) moderate to severe movement pain, and POD3 pain rescue medication were significant prognostic predictors of PAU after discharge. The area under the curve (AUC) of the 3-month, 6-month, and 12-month nomogram receiver operating characteristic (ROC) curves were calculated to be 0.741, 0.736, and 0.781.

Conclusion

PAU was defined as more than three months of NSAID-based oral analgesic use after TKA. Prognostic predictors of PAU after TKA were identified, and visualized nomogram was plotted and evaluated. The evaluation indicated that the prediction model had the good predictive ability and was a valuable tool for predicting PAU after discharge.

Outcomes Vary Significantly Using a Tiered Approach to Define Success After Total Knee Arthroplasty

BACKGROUND

Patient-reported outcome measures (PROM) allow assessment of clinical outcomes following primary total knee arthroplasty (TKA). The purpose of this study is to use progressively more stringent definitions of success to examine clinical outcomes of primary TKA at 1 year postoperatively and to determine which demographic variables were associated with achieving clinical success.

METHODS

The American Joint Replacement Registry was queried from 2012 to 2020 for primary TKA. Patients who completed the following PROMs preoperatively and 1 year postoperatively were included: Western Ontario and McMaster Universities Arthritis Index (WOMAC), Knee Injury and Osteoarthritis Outcome Score (KOOS), and KOOS for Joint Replacement (KOOS JR). Mean PROM scores were determined for each visit and between-visit changes were evaluated using paired t-tests. Rates of achievement of minimal clinically important difference (MCID) by distribution-based and anchor-based criteria, Patient Acceptable Symptom State, and substantial clinical benefit were calculated. Logistic regression was used to evaluate the association between demographic variables and odds of clinical success.

RESULTS

In total, 12,341 TKAs were included. Mean improvement in PROM scores were as follows: KOOS JR, 29; WOMAC-Pain, 33; and WOMAC-Function, 31 (P < .0001 for all). Rates of achievement of each metric were the following: distribution-based MCID, 84%-87%; anchor-based MCID, 46%-79%; Patient Acceptable Symptom State, 54%-82%; and substantial clinical benefit, 68%-81%. Patient age and gender were the most influential demographic factors on achievement of clinical success.

CONCLUSION

Clinical outcomes at 1 year following TKA vary significantly when using a tiered approach to define success. A tiered approach to interpretation of PROMs should be considered for future research and clinical assessment.

Pre-Arthritic/Kinematic Alignment in Fixed-Bearing Medial Unicompartmental Knee Arthroplasty Results in Return to Activity at Mean 10-Year Follow-up

BACKGROUND

The optimal alignment strategy in unicompartmental knee arthroplasty (UKA) is debated. Recent studies have suggested that kinematic alignment may lead to improved biomechanics and outcomes. The aim of the present study was to determine if pre-arthritic/kinematic alignment of knees would result in sustained long-term restoration of function, without conversion to total knee arthroplasty (TKA), following non-robotically assisted, fixed-bearing medial UKA.

METHODS

A total of 236 UKAs were performed from 2000 to 2015. Of these, a total of 150 medial UKAs met the inclusion criteria and were included in the study. There were 76 UKAs performed in female patients. The mean age was 65 ± 10 years and the mean body mass index was 28.6 ± 5 kg/m2. Patients with ≥15° of varus alignment preoperatively were excluded. Varus deformity was evaluated with use of the hip-knee-ankle angle (HKAA). Pre-arthritic/kinematic alignment was estimated with use of an arithmetic HKAA (aHKA, calculated as the medial proximal tibial angle minus the lateral distal femoral angle). We defined pre-arthritic/kinematic alignment as a postoperative HKAA within 3° of the aHKA. The primary outcome measures were the Knee Injury and Osteoarthritis Outcome Score (KOOS) Activities of Daily Living and Sport subscales, including the percentage of patients who met the patient acceptable symptom state (PASS) for these measures. Failure was defined as conversion to TKA.

RESULTS

The mean follow-up was 10 years (range, 4 to 20 years), with a mean survival time estimate of 18.3 years (95% confidence interval [CI], 17.8 to 18.8). The rate of conversion to TKA was 3% (5 of 150 UKAs). Postoperatively, 127 (85%) of 150 knees were pre-arthritic/kinematically aligned, and 23 knees (15%) were not. Patients with compared to those without pre-arthritic/kinematically aligned knees had significantly longer mean survival (18.6 years; 95% CI, 18.2 to 19) compared with 15.4 years; 95% CI, 13.4 to 17.5, respectively; p = 0.008) and higher KOOS Activities of Daily Living (92 compared with 74; p < 0.001) and Sport subscale scores (74 compared with 36; p < 0.001). A greater proportion of knees in the pre-arthritic/kinematically aligned cohort met the PASS for the KOOS Activities of Daily Living (85%, 106 of 125 knees) and Sport subscales (109 of 125, 87%) compared with the non-pre-arthritic/kinematically aligned cohort (28% and 57%, respectively; p < 0.01).

CONCLUSIONS

Pre-arthritic/kinematically aligned knees in this non-robotically assisted fixed-bearing medial UKA cohort had superior outcomes, including the KOOS Activities of Daily Living and Sport subscales and achievement of the PASS for these measures, compared with non-pre-arthritic/kinematically aligned at an average of 10 years after UKA. Knees that fell within 3° of a simple aHKA measurement on a 3-foot (1-m)-long standing radiograph had greater longevity and return to activities.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Satisfaction and Health-Related Quality of Life Following Hip and Knee Arthroplasty Surgeries in Indian Patients: A Cross-Sectional Study

Introduction

Recently, the patient-reported outcome measures (PROMs) have been considered as the most important assessment tool for surgical outcome evaluation in arthroplasty. However, no study from the Indian subcontinent has evaluated the PROM in the total hip (THA) and knee (TKA) arthroplasties.

Materials and Methods

This cross-sectional study evaluated the health-related quality of life (HRQoL) of 1244 North Indian patients following primary THA and TKA who had at least one-year follow-up. This study included 617 patients with 664 THA and 627 patients with 1152 TKA. The patients were asked to answer the EQ-5D-5L questionnaires and EQ-VAS in their own languages. The EQ-5D-5L values were used to derive level frequency scores (LFS) with validated Indian norms of EuroQoL.

Results

Ninety percent of THA and 82% of TKA patients rated excellent HRQoL using EQ-VAS. The regression analysis revealed age, gender, etiology and brand of prosthesis had a significant impact on EQ-5D-5L following THA. However, gender and simultaneous bilateral surgery were found to be important predictors of outcome in TKA. The mean value of LFS for THA was 0.95 ± 0.12 and TKA was 0.88 + 0.24 (p < 0.001). However, There was no difference in LFS between THA and TKA when only elderly patients (> 60 years) were considered (p = 0.168).

Conclusion

THA patients reported better HRQoL than TKA in the Indian subcontinent. One of the factors for a better outcome in hip arthroplasty was the relatively younger age of the patients. Patients above 60 years of age reported similar levels of statisfactior in both THA and TKA.

Supplementary Information

The online version contains supplementary material available at 10.1007/s43465-021-00589-x.

Improved total knee arthroplasty pain outcome when joint gap targets are achieved throughout flexion

PURPOSE

Achieving a balanced knee is accepted as an important goal in total knee arthroplasty; however, the definition of ideal balance remains controversial. This study therefore endeavoured to determine: (1) whether medio-lateral gap balance in extension, midflexion, and flexion are associated with improved outcome scores at one-year post-operatively and (2) whether these relationships can be used to identify windows of optimal gap balance throughout flexion.

METHODS

135 patients were enrolled in a multicenter, multi-surgeon, prospective investigation using a robot-assisted surgical platform and posterior cruciate ligament sacrificing gap balancing technique. Joint gaps were measured under a controlled tension of 70-90 N from 10°-90° flexion. Linear correlations between joint gaps and one-year KOOS outcomes were investigated. KOOS Pain and Activities of Daily Living sub-scores were used to define clinically relevant joint gap target thresholds in extension, midflexion, and flexion. Gap thresholds were then combined to investigate the synergistic effects of satisfying multiple targets.

RESULTS

Significant linear correlations were found throughout extension, midflexion, and flexion. Joint gap thresholds of an equally balanced or tighter medial compartment in extension, medial laxity ± 1 mm compared to the final insert thickness in midflexion, and a medio-lateral imbalance of less than 1.5 mm in flexion generated subgroups that reported significantly improved KOOS pain scores at one year (median ∆ = 8.3, 5.6 and 2.8 points, respectively). Combining any two targets resulted in further improved outcomes, with the greatest improvement observed when all three targets were satisfied (median ∆ = 11.2, p = 0.002).

CONCLUSION

Gap thresholds identified in this study provide clinically relevant and achievable targets for optimising soft tissue balance in posterior cruciate ligament sacrificing gap balancing total knee arthroplasty. When all three balance windows were achieved, clinically meaningful pain improvement was observed.

LEVEL OF EVIDENCE

Level II.

Effectiveness of client-centered intervention delivered with face-to-face and telerehabilitation method after total knee arthroplasty—A pilot randomized control trial

Introduction

Total knee arthroplasty (TKA) negatively affects the quality of life, perceived occupational performance, and satisfaction. Face-to-face rehabilitation services have been adversely affected by problems such as time, cost, accessibility, and the COVID-19 pandemic. The telerehabilitation (TR) method is recommended for these problems. This pilot study was planned to examine the comparison of client-centered (CC) intervention with TR and face-to-face (FF) method on quality of life, perceived occupational performance, and satisfaction after TKA.

Methods

Forty-eight older adults that after TKA (13 men and 35 women) were randomized to the TR group ( n = 24; 68.25 ± 3.32 years) or FF group ( n = 24; 68.91 ± 2.56 years). The Nottingham Health Profile (NHP) was used to assess the quality of life, and the Canadian Occupational Performance Measure (COPM) was used to assess perceived occupational performance and satisfaction.

Results

There was no difference in all parameters between the groups before and after the intervention program (p > .05). The intervention consisting of 4 days a week for 4 weeks and 45 min sessions applied with both methods had a strong effect size (p < .001 for all).

Conclusion

As a result, CC intervention applied with both methods in the first postoperative week increased quality of life, perceived occupational performance, and satisfaction. Trail Registration: NCT04969432

Preoperative Patient-Reported Outcomes Measurement Information System Global Health Scores Predict Patients Achieving the Minimal Clinically Important Difference in the Early Postoperative Time Period After Total Knee Arthroplasty

INTRODUCTION

The patient-specific factors influencing postoperative improvement after total knee arthroplasty (TKA) are important considerations for the surgeon and patient. The primary purpose of this study was to determine which patient demographic factors influence the postoperative Patient-Reported Outcomes Measurement Information System (PROMIS) Global Health (GH) scores. In addition, we aimed to compare the prognostic utility of preoperative PROMIS-GH scores and the Knee Injury and Osteoarthritis Outcome Score for Joint Replacement (KOOS-JR) in predicting postoperative improvement.

METHODS

This retrospective cohort study of a consecutive series of patients who underwent primary, unilateral TKA analyzed prospectively collected KOOS-JR and PROMIS-GH surveys. PROMIS-GH includes physical health (PH) and mental health scores. Patient demographic and presurgical characteristics were evaluated for prognostic capability in predicting postoperative improvement in the PROMIS scores and achievement of the minimal clinically important difference (MCID). Receiver operating characteristic curves were used to understand the prognostic thresholds of the preoperative PROMIS score and KOOS-JR for predicting MCID achievement.

RESULTS

A total of 872 patients were included. Although unadjusted analyses showed associations between patient demographic factors and PROMIS-PH scores, multivariable regression analysis for predictors of MCID achievement demonstrated that PROMIS-PH was the only significant preoperative variable. Receiver operating characteristic analysis revealed that the area under the curve of PROMIS-PH (0.70; 95% CI, 0.67 to 0.74) was less than that of the KOOS-JR (0.77; 95% CI, 0.73 to 0.81; P = 0.032). Sensitivity and specificity for achieving the MCID were maximized for preoperative PROMIS-PH scores of ≤ 38 (59% and 70%) and for preoperative KOOS-JR ≤ 51 (71% and 69%).

CONCLUSIONS

Preoperative KOOS-JR and PROMIS-PH scores predict clinically meaningful improvement after TKA. The KOOS-JR has greater prognostic utility in the early postoperative period.

LEVEL OF EVIDENCE

Level III, Prognostic Study.

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.

The Effectiveness of Client-Centered Intervention With Telerehabilitation Method After Total Knee Arthroplasty

There is known to be a decrease in quality of life and perceived occupational performance and satisfaction following total knee arthroplasty (TKA). This study was planned to examine the effectiveness of a client-centered (CC) intervention with the telerehabilitation (TR) method on the quality of life, perceived occupational performance, and satisfaction after TKA. A total of 38 patients who had undergone TKA were randomly assigned to the CC and control groups. A 12-day intervention program was applied to the CC group. The Nottingham Health Profile (NHP) and Canadian Occupational Performance Measure (COPM) were applied before and after intervention. The 12-day intervention showed a strong effect on all parameters in the CC group (p<.001). In the postintervention comparisons, a significant difference was found in favor of the CC group (p < .001). CC interventions with the TR method can be used in post-TKA interventions.

Incidence and risk factors related to fear of falling during the first mobilisation after total knee arthroplasty among older patients with knee osteoarthritis: A cross-sectional study

BACKGROUND

The factors that lead to the fear of falling among older people after total knee arthroplasty (TKA) are poorly understood. The present study aims to examine the fear of falling among such patients and to determine the factors that are associated with that fear.

METHODS

A total of 285 patients aged ≥65 with knee osteoarthritis who underwent TKA at an orthopaedic hospital between November 2019 and May 2020 completed surveys about their own first mobilisation after TKA. They were asked to indicate whether they were afraid of falling by asking a single question, and what their pain level was on a visual analogue scale. They also completed the General Anxiety Disorder scale, the Geriatric Depression Scale-Short Form and the Social Support Rating Scale. Multivariate logistic regression was used to identify risk factors for fear of falling during the first mobilisation after TKA. This study was reported in compliance with the STROBE checklist for cross-sectional studies (see Supplementary File S1).

RESULTS

Just over half (56.5%) of participants reported being afraid of falling. Multivariate logistic regression identified three independent risk factors that explained a total of 31% of the variance in the fear of falling: female sex (odds ratio (OR) = 4.21, 95% confidence interval (CI) = 2.35-7.55), higher body mass index (OR =3.93, 95% CI =1.53-10.10) and higher anxiety (OR = 1.56, 95% CI = 1.37-1.78).

CONCLUSIONS

Many older patients fear falling when they begin to move after TKA, particularly women and those with higher body mass index or anxiety. These subgroups may merit special attention from healthcare professionals to mitigate their fears and optimise recovery after TKA.