Severe arthritis predicts greater improvements in function following total knee arthroplasty

The achievement of pre-operative expectations in patients undergoing knee arthroplasty: a cohort study evaluating unique patient goals

BACKGROUND

Total knee arthroplasty (TKA) is a common procedure employed to treat end-stage osteoarthritis. While TKA is generally believed to have acceptable outcomes, many patients report pain or functional deficits not in line with their expectation following the procedure. It has been postulated that patient's pre-operative expectations regarding post-operative treatment outcomes play a significant role in satisfaction. It is therefore important to assess if the outcomes of surgery truly align with patient's individual expectations. Thus, the purpose of this study was to determine the degree to which patient expectations of TKA are achieved and the contribution of TKA to achieving patient goals one year after surgery.

METHODS

A consecutive sample of 110 patients booked for total knee arthroplasty were asked to identify their most important goals to inform the Direct Questioning of Objectives Index (DQO Index, range 0 to 1) and identify their surgical goals and grade their expectation that a knee arthroplasty would achieve each goal on an 11-point scale. One year after surgery, the DQO Index was repeated to assess their current ability to achieve each pre-operative goal, and asked to estimate the contribution of their knee arthroplasty in achieving each goal. Mean differences between baseline and one year follow-up were calculated regarding the DQO Index and expected achievement of pre-operative goals.

RESULTS

According to the DQO Index at one year, patients improved from a poor quality of life pre-operatively (mean ± standard deviation: 0.20 ± 0.18) to moderately high quality of life (mean ± standard deviation: 0.71 ± 0.21) reflecting a large improvement in ability to achieve each goal. Although achievement improved, for each goal, the patient estimates of the extent to which the knee arthroplasty had contributed to achieving the goal was lower than their initial expectation provided pre-operatively (mean difference range: 0.6 to 1.9 on an 11-point scale).

CONCLUSION

Patients undergoing TKA have high expectations that their surgery will address their primary goals. Despite surgery largely achieving these goals (improved pain and function), the extent to which the goals were achieved was lower than patients had expected pre-operatively.

Staged Bilateral Total Knee Arthroplasty: Differing Results Comparing the First and Second Knees

BACKGROUND

Patients often prefer one knee over the other following staged bilateral total knee arthroplasty (BTKA). Our study compared patient-reported outcomes scores of each knee following BTKA and identified factors that may contribute to the identified discrepancies.

METHODS

All patients who underwent staged BTKA between July 2014 and August 2022 were identified. The patient-reported outcomes were collected preoperatively and at 2 weeks, 6 weeks, 1 year, and 2 years postoperatively. Each knee's results were compared using paired t-tests and McNemar tests. Preoperative Kellgren-Lawrence Grade (KLG), postoperative range of motion (ROM), reoperation rates, and manipulations under anesthesia (MUAs) were collected. Results were stratified based on time between TKAs (< 3 months, 3 to 12 months, 1 to 2 years, and > 2 years).

RESULTS

There were 911 patients who underwent staged BTKA, with a mean 4.1-year follow-up. The ROM, patient satisfaction, MUAs, and reoperations were not significantly different between knees. Comparing the KLG of the first and second knees, 71% had the same KLG for both knees, 21% had a lower KLG, and 7% of the second knees had a higher KLG. The first knee had greater pain reduction (-10.6 at 2 weeks, -27.4 at 6 weeks) compared to the second (9.3 at 2 weeks, -8.1 at 6 weeks) (P < .0001) and better improvement in Knee Injury and Osteoarthritis Outcome Score for Joint Replacement (KOOS JR) score (8.5 at 2 weeks, 16.9 at 6 weeks) compared to the second (-5.8 at 2 weeks, 5.0 at 6 weeks) (P < .0001). The 1-year outcomes between first and second knees, or recovery curves, were not different when stratifying by time between TKAs.

CONCLUSIONS

The second knee in a staged BTKA has less delta improvement in KOOS JR and pain scores at early follow-up, likely due to higher starting KOOS JR and Patient-Reported Outcomes Measurement Information System scores, despite similar final patient satisfaction and clinical outcome measures. Lower KLG in the second total knee arthroplasty (TKA) may contribute to these findings. An MUA after the first TKA is highly predictive of an MUA after the second TKA.

Establishing a hierarchy of total knee arthroplasty patients' goals and its congruity to health professionals' perceptions: a cohort study

BACKGROUND

To formulate a hierarchy of primary goals of patients prior to total knee arthroplasty (TKA) and evaluate the agreement between patients and health professionals regarding this hierarchy of patient goals.

METHODS

The five most important goals for each of 110 consecutive patients booked for total knee arthroplasty between June and October 2019 were identified. Goals were grouped into themes and then a hierarchy formulated. This hierarchy was randomized and provided to 94 health professionals, including orthopaedic surgeons (n = 49), rheumatologists (n = 16), physiotherapists (n = 16) and general practitioners (n = 13). These health professionals ranked the provided goals based on their belief of what was most important to patients.

RESULTS

Ten overarching goals were identified, with the five most important goals to patients being improving mobility, reducing knee pain, improving daily tasks, participating in social & leisure activities and regaining knee range of motion. Health professionals ranked these goals highly similar to patients with the exceptions being that health professionals ranked quality of life near the top of the hierarchy (much higher than patients) and ranked improving mobility in the bottom half (much lower than patients). Ranking of these goals was similar between each health professional group.

CONCLUSION

Pain and mobility are the most important goals to patients, with health professionals correctly identifying these as such. However, health professionals ranked quality of life higher, and mobility lower in the hierarchy than patients. This incongruity should be considered by health professionals when educating and communicating treatment outcomes.

Anatomical site of radiographic degeneration is an independent variable influencing outcome of total knee arthroplasty

OBJECTIVES

We aimed to determine whether the site of anatomical degenerative change could be identified as an independent risk factor influencing clinical outcome of total knee arthroplasty (TKA) 12 months postoperatively.

METHODS

We compared preoperative, postoperative and the change observed in Oxford Knee Score (OKS) amongst TKA patients categorised as primarily medial, lateral or patellofemoral osteoarthritis (PFJOA). Multivariable regression analysis was conducted on 434 consecutive knees in 333 patients, adjusting for sex, age and body mass index (BMI).

RESULTS

Adjusted estimates showed that preoperatively, patients with medial and lateral osteoarthritis (OA) had a lower mean OKS of 2.1 (p ​= ​0.049) and 2.3 (p ​= ​0.056) points respectively, while those with PFJOA had mean scores 2.7 points higher (p ​= ​0.062). There was no statistically significant difference between compartments in absolute postoperative OKS. The greatest improvement of 30.1 points (95% confidence interval (CI) 16.9-36.0, p ​= ​0.012) in OKS was observed for those with lateral OA, followed by 28.9 points (95% CI 16.7-35.3, p ​= ​0.049) for those with medial OA. The improvement observed postoperatively in patients with PFJOA was less than that observed for the average of the cohort at 24.5 (95% CI 11.5-29.7, p ​= ​0.088).

CONCLUSIONS

The site of compartmental involvement in knee OA is an independent factor influencing clinical outcome of TKA. With arthroplasty registry adoption of patient-reported outcome measures (PROMs), this study supports precise anatomical categorisation of knee OA in outcome studies.

LEVEL OF EVIDENCE

Level III, Retrospective consecutive clinical study.

Low grade of radiographic osteoarthritis predicts unsatisfactory response of the contralateral knee replacement in two-stage bilateral total knee arthroplasty

PURPOSE

It is difficult to counsel patients with bilateral osteoarthritis who are unsatisfied with their first knee replacement as to whether they are likely to have a better outcome after the contralateral knee is replaced. The purpose of this study was to determine whether predictive factors can be found to prognosticate outcome of the second-side knee replacement when a patient has an unsatisfactory response to the first, with the hypothesis that predictors, such as prosthetic factors and radiographic level of osteoarthritis, may be able to predict a satisfactory response to the contralateral knee replacement.

MATERIALS AND METHODS

An analysis of staged bilateral knee replacements performed at a tertiary arthroplasty centre from 2012 to 2018 was undertaken. A total of 550 knee replacements in 275 patients were included in this study. The primary variable measured was the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score. Satisfactory response to surgery was defined as a WOMAC score improved by 17 points or more, and 56 or greater. Patients who did not achieve a satisfactory response with their first knee replacement were further analysed for predictive factors (age, sex, pre-operative score, mental score, socioeconomic status, type of prosthesis, use of navigation, patella resurfacing and radiographic osteoarthritis) of an unsatisfactory response for their contralateral knee replacement.

RESULTS

Overall, 44 (16%) patients failed to achieve a satisfactory response from both their first and contralateral knee replacements. The factor most predictive of an unsatisfactory response to their first knee replacement was pre-operative mental health score. However, in patients who did not achieve a satisfactory response with their first knee replacement, radiographic osteoarthritis, as measured by the Kellgren-Lawrence (KL) score was the main predictor of satisfactory response for their contralateral knee replacement. Only patients with KL grade 4 osteoarthritis were likely to have a satisfactory response with their contralateral knee replacements (KL4 versus KL3, Odds ratio 3.57 (CI 1.26-10.03) p = 0.016*). Patients with KL grade 3 osteoarthritis were unlikely to have a satisfactory response, and in this series, no patient with KL grade 2 osteoarthritis had a satisfactory response.

CONCLUSION

In a patient who has an unsatisfactory response to their first knee replacement, the best predictor of achieving a satisfactory response to his/her contralateral knee replacement is the level of radiographic osteoarthritis in that knee.

LEVEL OF EVIDENCE

IV: Retrospective Cohort study.

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.

Clinical Course of Pain and Function Following Total Knee Arthroplasty: A Systematic Review and Meta-Regression

BACKGROUND

Total knee arthroplasty (TKA) is widely considered a successful intervention for osteoarthritis and other degenerative knee diseases. This study addresses the need for a high-quality meta-analysis that outlines the clinical course of pain and function post-TKA.

METHODS

The review included prospective cohort studies assessing pain or function of patients undergoing primary TKA at baseline (preoperatively) and at least 2 additional time points including one at least 12 months postoperatively. Two reviewers independently screened references, extracted data, and assessed risk of bias using the Quality in Prognosis Studies tool. The time course of recovery of pain and function was modeled using fractional polynomial meta-regression.

RESULTS

In total, 191 studies with 59,667 patients were included, most with low risk of bias. The variance-weighted mean pain score (/100, 0 = no pain) was 64.0 (95% confidence interval [CI] 60.2-67.7) preoperatively, 24.1 (95% CI 20.3-27.9) at 3 months, 20.4 (95% CI 16.7-24.0) at 6 months, and 16.9 (95%CI 13.6-20.3) at 12 months, and remained low (10.1; 95% CI 4.8-15.4) at 10 years postoperatively. The variance-weighted mean function score (/100, 0 = worst function) was 47.1 (95% CI 45.7-48.4) preoperatively, 72.8 (95% CI 71.3-74.4) at 3 months, 76.3 (95% CI 74.7-77.8) at 6 months, and 78.1 (95%CI 76.4-79.7) at 12 months. Function scores were good (79.7; 95% CI 77.9-81.5) at 10 years postoperatively.

CONCLUSION

Patients undergoing primary TKA can expect a large and rapid but incomplete recovery of pain and function in the first postoperative year. At 10 years, the gains in pain scores may still remain while there is an improvement in function.

Arthroscopic partial meniscectomy: did it ever work?

Arthroscopic partial meniscectomy (APM) is one the most common orthopedic surgical procedures. The most common indication for APM is a degenerative meniscal tear (DMT). High-quality evidence suggests that APM does not provide meaningful benefits in patients with DMTs and may even be harmful in the longer term. This narrative review focuses on a fundamental question: considering the history and large number of these surgeries, has APM ever actually worked in patients with DMT? A truly effective treatment needs a valid disease model that would biologically and plausibly explain the perceived treatment benefits. In the case of DMT, effectiveness requires a credible framework for the pain-generating process, which should be influenced by APM. Basic research, pathoanatomy, and clinical evidence gives no support to these frameworks. Moreover, treatment of DMT with an APM does not align with the traditional practice of medicine since DMT is not a reliable diagnosis for knee pain and no evidence-based indication exists that would influence patient prognosis from APM. A plausible and robust explanation supported by both basic research and clinical evidence is that DMTs are part of an osteoarthritic disease process and do not contribute to the symptoms independently or in isolation and that symptoms are not treatable with APM. This is further supported by the fact that APM as an intervention is paradoxical because the extent of procedure and severity of disease are both inversely associated with outcome. We argue that arthroscopic treatment of DMT is largely based on a logical fallacy: post hoc ergo propter hoc.

Observing the use of knee arthroplasty appropriateness tools in clinical practice: do appropriateness criteria tools predict surgeon decision-making?

OBJECTIVE

The primary aim of this study was to evaluate the agreement between surgeons and two validated total knee arthroplasty (TKA) appropriateness tools, and secondarily to compare Australian appropriateness rates to those reported internationally.

METHODS

A consecutive sample of patients from one public hospital arthroplasty clinic and a convenience sample from private rooms of surgeons in New South Wales, Australia (n = 11), referred for surgical opinion regarding TKA were enrolled over 1 year. Surgeons applied appropriateness tools created by Escobar et al. and the American Academy of Orthopaedic Surgeons (AAOS). Correlation between the appropriateness tools and surgeon's decisions were evaluated.

RESULTS

There were 368 patients enrolled, and contrasting rates of being "appropriate" for surgery were identified between the Escobar (n = 109, 29.6%) and AAOS (n = 292, 79.3%) tools. Surgeon agreement with the Escobar tool was substantial (ĸ = 0.61, 95%CI: 0.53-0.69) compared to slight with the AAOS tool (ĸ = 0.11, 95%CI: 0.06-0.16). Of those advised against TKA (n = 179, 48.6%), the AAOS tool suggested many patients (n = 111, 62.0%) were "appropriate" compared to the Escobar tool (n = 12, 6.7%).

CONCLUSIONS

Surgeons rated patients seeking opinion for TKA as appropriate over half the time, however the AAOS tool had low correlation with surgeons as opposed to the Escobar tool. This was illustrated by both tools rating a majority of patients to be operated on as appropriate, but only the AAOS tool considering most patients not chosen for surgery to be appropriate. When comparing previously published appropriateness rates, appropriateness in Australia, USA, Spain and Qatar was found to be similar.

Arthritic progression secondary to meniscus root tear treated with knee arthroplasty demonstrates similar outcomes to primary osteoarthritis: a matched case-control comparison

PURPOSE

There is limited data comparing the outcomes of knee arthroplasty for arthritis secondary to meniscus root tear versus primary osteoarthritis. The aim of this 2:1 matched case control series was to compare outcomes in patients who underwent arthroplasty for arthritis following a meniscus root tear (root tear cohort-"RTC") with a control group of patients with primary osteoarthritis (primary osteoarthritis-"controls"). The authors hypothesized that the meniscus root tear patients would have similar clinical outcomes, return to activity, complication and reoperation rates as their matched controls.

METHODS

A consecutive series of patients who had a clinically and radiographically confirmed meniscus root tear between 2002 and 2017 at a mean 4.8 year follow-up that developed secondary arthritis were matched 2:1 by laterality, surgery, age at surgery, date of surgery, sex, and surgeon to a control group of patients with primary osteoarthritis, without a root tear, who underwent arthroplasty. No patients were lost to follow-up. Patient demographics, Kellgren-Lawrence grades at the time of surgery, pre- and post-operative Knee Society Score pain and function scores, Tegner score, complications, and survival free of reoperation were analyzed between groups.

RESULTS

A total of 225 subjects were identified, including 75 root tear cohort patients (13 UKA, 62 TKA) and 150 control patients. The root tear cohort had significantly lower Kellgren-Lawrence grades than the control group at the time of arthroplasty (p ≤ 0.001), but similar baseline pre-operative Knee Society Score pain, Knee Society Score function, and Tegner activity scale score. Post-operatively, Knee Society Score pain scores were comparable, and root tear cohort Knee Society Score function scores statistically significantly improved (p ≤ 0.007). Complication rates and survival free of reoperation at final follow-up were not statistically significantly different between groups.

CONCLUSION

Patients treated with arthroplasty for secondary arthritis after a meniscus root tear demonstrated less severe radiographic arthritis, but similar pre-operative pain levels compared to matched controls with primary osteoarthritis. The root tear cohort patients demonstrated improved outcomes with respect to function, and similar outcomes with respect to pain, activity level, complication rates, and reoperation rates. The authors conclude that arthroplasty can be a reliable option for selected patients with an irreparable root tear and ongoing pain and dysfunction refractory to non-operative management, even in the setting of less advanced osteoarthritis on X-ray.

LEVEL OF EVIDENCE

III.

Local Efficacy of Corticosteroids as an Adjuvant for Periarticular Cocktail Injection in Simultaneous Bilateral Total Knee Arthroplasty: A Prospective Randomized Double-Blind Controlled Trial

Multimodal cocktail periarticular injections comprising corticosteroids are the most suggested therapy for postoperative discomfort and swelling following total knee arthroplasty (TKA). Nevertheless, previous findings cannot be applied to instances of unilateral total knee arthroplasty on bilateral knees. This randomized, prospective, double-blind, controlled clinical study examines the efficacy as well as safety of periarticular multimodal cocktail injection along or sans corticosteroids in certain situations. The 60 patients (120 knees) that experienced concurrent bilateral total knee arthroplasty were provided periarticular injections along additional betamethasone (7 mg) in the randomized knee, as well as the other knee, where corticosteroid was not administered. Key results were “pain scores at rest as well as in action” on a visual analogue scale of 11 pt. Other results included motion range, swelling of the thigh, Hospital for Special Surgery score (HSS score), and adverse effects were measured between the two sides. No statistically promising variations were found in the visual analogue scale ranking, motion range, girth of the thigh, and HSS score, as well as complications between the two sides. The impact on treatment outcomes was maintained between the knees on postoperative day 3 or at 3 months of follow-up. Multimodal periarticular injection without corticosteroid will alleviate postoperative swelling and pain. More studies are needed for the use of betamethasone as a corticosteroid in periarticular multimodal cocktail injections. This Chinese Clinical Trial Registry is registered with ChiCTR-OPC-17013503, dated 2017-11-23, available from http://www.chictr.org.cn/showproj.aspxproj=23146.

Online Decision Aids for Knee Arthroplasty: An Environmental Scan

BACKGROUND

Knee arthroplasty is a high-risk, resource-intensive procedure that should be reserved for patients in whom the benefit will outweigh the risks. The provision of high-quality, publicly available decision aids can help patients to balance the benefits against the harms of treatments and to assist informed decision-making. The aim of this study was to identify and evaluate the content and readability of freely available knee arthroplasty decision aids.

METHODS

A systematic search using an environmental scan methodology of publicly available online materials was performed in December 2018. Included materials were assessed for quality using the International Patient Decision Aid Standards instrument (IPDASi), understandability and actionability from a patient's perspective using the Patient Education Materials Assessment Tool (PEMAT), and readability grade level using the Flesch-Kincaid Grade Level and the Gunning Fog Index.

RESULTS

Of 761 online materials screened, 26 decision aids were identified. Only 18 (69%) may be considered to meet criteria to be defined as a decision aid and 4 (15%) met criteria suggesting that the material did not introduce potential harmful bias according to the IPDASi. The mean score (and standard deviation) for all decision aids was 74% ± 12% for understandability and 44% ± 19% for actionability using the PEMAT. Readability indices indicated a mean minimum reading level of Grade 10 (10.8 ± 2.5). No decision aid included a wait-and-see option.

CONCLUSIONS

Few high-quality decision aids exist for patients considering knee arthroplasty and none include a wait-and-see option. Many do not provide actionable options and are pitched at above-average reading levels. Developers need to address these issues to encourage high-quality decision-making, especially for those with low health literacy.

Reliability of three radiographic classification systems for knee osteoarthritis among observers of different experience levels

OBJECTIVE

To assess the intra- and inter-observer reliability of three commonly referenced radiographic classification systems for knee osteoarthritis in a cohort of arthroplasty candidates.

MATERIALS AND METHODS

Pre-operative radiographs of 112 patients who subsequently underwent primary total knee arthroplasty were evaluated by four independent observers of varying experience. Each x-ray was de-identified, randomised, and classified according to the International Knee Documentation Committee, Kellgren-Lawrence, and Ahlbäck classifications. After a 2-week interval period, each x-ray was again randomised and re-classified.

RESULTS

Regarding inter-observer reliability, the Ahlbäck and Kellgren-Lawrence classifications were shown to have 'substantial agreement' (AC 0.79 and 0.85 respectively), and the IKDC was shown to have 'almost perfect agreement' (AC 0.97). Regarding intra-observer reliability, the two more experienced observers demonstrated 'good' or 'excellent' reliability for all classification systems, and the two less experienced observers demonstrated 'moderate' intra-observer reliability for all classification systems.

CONCLUSION

The International Knee Documentation Committee, Kellgren-Lawrence, and Ahlbäck radiographic classifications demonstrated adequate intra- and inter-observer reliability, supporting their potential implementation in surgical practice, or in epidemiological and clinical studies of knee osteoarthritis in a comparable cohort of patients. Clinical experience was positively correlated with intra-observer reliability. Whilst the International Knee Documentation Committee classification demonstrated the greatest reliability, this is likely due to its conservative definitions, and the Ahlbäck and Kellgren-Lawrence classifications are likely more reflective of the spectrum of disease severity encountered in an older patient cohort.

Higher treatment effect after total knee arthroplasty is associated with higher patient satisfaction

PURPOSE

The aim of this study was to investigate what influence the treatment effect after total knee arthroplasty (TKA) had on patient satisfaction.

METHODS

Prospective registry data of a University-based arthroplasty centre were used. 582 patients with unilateral bicondylar TKA were analyzed. Treatment effect (TE) was deduced from Oxford Knee Score (OKS) before and one year after surgery. Positive values correspond to improved symptoms (maximum 1.0 reflect no symptoms at all) and negative values correspond to deterioration of symptoms. Satisfaction on a visual-analogue scale from 0 to 10 and the willingness to undergo TKA surgery again was assessed one year after surgery.

RESULTS

The mean OKS improved from 22.1 before to 36.7 one year after TKA. Treatment effects ranged from 1.0 to -0.62 with a mean TE of 0.56. Taking an individual treatment effect of 0.2 as a cut-off between responder and non-responder, a total of 85.8% would be classified as responder after TKA. The mean satisfaction score with the TKA was 8.1. There was a significant correlation between the individual treatment effect and satisfaction after TKA (p < 0.001). The majority of patients (84.5%) would undergo surgery again. Patients not willing to undergo surgery again or those uncertain about this had lower satisfaction scores, a lower treatment effect and were more often female compared to patients who would undergo surgery again.

CONCLUSION

Higher individual treatment effects resulted in higher patient satisfaction and willingness to undergo surgery again. However, some patients with a relatively low treatment effect were highly satisfied, which indicates the need for both information.

LEVEL OF EVIDENCE

II.

More Severe Radiographic Osteoarthritis Is Associated With Increased Improvement in Patients' Health State Following a Total Knee Arthroplasty

BACKGROUND

To assess whether preoperative radiological severity of osteoarthritis (OA) is related to the level of improvement in patients' health state measured 1 year after total knee arthroplasty (TKA).

METHODS

Radiographic severity of OA was graded using the Kellgren-Lawrence (KL) classification. Two independent observers were blinded to patients' outcome scores. Health-related quality of life was measured using EQ-5D-3L preoperatively and at 12-month follow-up. The 5 dimensions of the EQ-5D were converted into a health state index score. The association between KL grade and improvement in health state score was analyzed using multiple linear regression.

RESULTS

Among 156 consecutive patients (68% females, mean age 69 years) who underwent primary TKA, 3 knees (2%) were classified as KL grade 2, 115 as KL grade 3 (74%), and 38 as KL grade 4 (24%). Follow-up rate was 77%. There was substantial intra-rater and inter-rater agreement (Cohen's kappa = 0.80 and 0.79). Most patients (64%) had clinically significant improvement in their health state score 1 year after TKA. However, after adjusting for relevant covariates, patients with severe OA (KL grade 4) were found to have significantly more improvement in their health state score than patients with mild or moderate OA (KL grade 2 or 3, respectively). Separate analysis of the 5 EQ-5D dimensions showed that the KL group differences were most evident in the "usual activities" and "pain/discomfort" dimensions.

CONCLUSION

Patients with severe OA have significantly more improvement in their usual activities and pain/discomfort 1 year after TKA than patients with less severe OA.

Asynchronous Bilateral Total Knee Arthroplasty: Predictors of the Functional Outcome and Patient Satisfaction for the Second Knee Replacement

BACKGROUND

The primary aim of this study is to identify independent preoperative predictors of outcome and patient satisfaction for the second total knee arthroplasty (TKA).

METHODS

A retrospective cohort of 454 patients undergoing an asynchronous (6 weeks or more apart) bilateral primary TKA were identified from an arthroplasty database. Patient demographics, comorbidities, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and Short Form-12 scores were collected preoperatively and 1 year postoperatively. Overall patient satisfaction was assessed at 1 year.

RESULTS

The 1 year WOMAC pain score (P = .01), and improvement in WOMAC pain (P < .001) and functional (P = .002) scores were significantly lower for the second TKA. Worse preoperative WOMAC pain, function, and stiffness scores were demonstrated to be independent predictors of improvement in the WOMAC pain, function, and stiffness scores, respectively, for both the first and second TKA. The overall rate of satisfaction with the first TKA was 94.0% and 94.7% for the second TKA (P = .67). The rate of satisfaction for the second TKA was 77.8% for patients that were dissatisfied with their first TKA, which was an independent predictor of dissatisfaction (P = .02).

CONCLUSION

Improvement in pain and function is less with the second TKA, but the satisfaction rate remains similar. There are common independent predictors for change in the WOMAC score for the first and second TKA; however, the predictors of satisfaction were different with no common factors. Patients that were dissatisfied with their first TKA were more likely to be dissatisfied with their second TKA.

LEVEL OF EVIDENCE II

Prognostic retrospective cohort study.

External Validity of a New Prediction Model for Patient Satisfaction After Total Knee Arthroplasty

BACKGROUND

The ability to identify patients at risk of dissatisfaction after total knee arthroplasty (TKA) remains elusive. This study's purpose was to determine the external validity of a recently published prediction model for patient satisfaction (PMPS) with the hypothesis that it would achieve similar predictive success in our study sample.

METHODS

A 10-question PMPS statistically derived from 5 patient-reported outcome questionnaires was tested for external validity in this prospective cohort investigation. The PMPS incorporates gender, age, stiffness, noise, and pain catastrophizing, with a score of 20 or greater predictive of satisfaction. As in the original study, to determine satisfaction the 2011 Knee Society Score (KSS) satisfaction subscale was collected at 3 months postoperatively. Two hundred seventy-four patients were administered the PMPS preoperatively, and 145 patients completed the KSS at 3 months postoperatively (53.0% response rate; 59% female; age, 64.9; body mass index, 32.5). A Bland-Altman analysis to assess agreement was performed.

RESULTS

One hundred thirty-three patients (91.7%) were satisfied and 12 (8.3%) were dissatisfied based on their postoperative KSS. The mean difference between the PMPS and KSS was 3.6 ± 8, but with a 95% prediction interval of -15.3 to 22.1 signifying almost no correlation. The PMPS did not predict any of the 12 dissatisfied patients postoperatively, and falsely predicted 5 patients to be dissatisfied of which 4 actually had a maximum postoperative KSS of 40.

CONCLUSION

A previously published, internally validated 10-question PMPS was unable to predict satisfaction after TKA in our external study sample. This study emphasizes the difficulty of developing a simple, but robust questionnaire that consistently predicts patient satisfaction after TKA.

Improved walking distance and range of motion predict patient satisfaction after TKA

PURPOSES

The focus in the evaluation of total knee arthroplasty has shifted from objective measures of implant position and knee function, to patient-reported outcome measures (PROMs). The relation between these two measures was investigated and the possibility of prediction of the patient satisfaction level was evaluated by defining thresholds for improvement of (1) range of motion (ROM), (2) 6-min walk test (6MWT), (3) sit-to-stand test (STS) and (4) quadriceps force after TKA?

METHODS

Fifty-seven patients were prospectively tested at preoperative and 6 months postoperative intervals. The ROM, 6MWT, STS-test and quadriceps force were evaluated. Two clusters were created based on the postoperative KOOS, OKS and the satisfaction subscore of the new KSS, cluster 1 consisted of patients with good to excellent PROMs, cluster 2 of patients with poorer PROMs. Patients in each cluster were more similar to each other than to those in the other cluster. Receiver operating characteristic (ROC)-curve analysis was used to identify thresholds for the functional outcomes that established cluster allocation. Multiple logistic regression was used to define a model to predict cluster allocation.

RESULTS

Patients with high postoperative PROMs (cluster 1 allocation) showed higher postoperative functional outcomes (p < 0.05). Thresholds for the improvement of ROM (≥ 5°, OR 6.3, 95% CI 1.23-31.84), 6MWT (≥ 50 m, OR 8.2, 95% CI 1.61-42.18) STS (≥ 1.05 s, OR 3, 95% CI 0.56-16.07) and normalized Q4 force (≥ 1.5 N/BMI, OR 2.5, 95% CI 0.49-12.89) were found to be predictors of cluster allocation. A model to predict the cluster allocation contained gender, ROM improvement and 6MWT improvement (sensitivity 91.1%, specificity 75%).

CONCLUSIONS

Thresholds for improvement of functional parameters can predict the patient satisfaction cluster. Patients, who are male, improve on the 6-min walk test with 50 m or more and have an increased range of motion of 5° or more, compared to the preoperative situation, are 6-8 times more likely of being satisfied after TKA. These tests are easy to use in clinical practice and can predict the level of patient satisfaction after TKA.

LEVEL OF EVIDENCE

Level II, prognostic study.

Fast-track total knee arthroplasty improved clinical and functional outcome in the first 7 days after surgery: a randomized controlled pilot study with 5-year follow-up

INTRODUCTION

Fast-track protocols (FP) are used more and more to optimize results after total knee arthroplasty (TKA). Many studies evaluating FP in TKA concentrate on clinical outcome and medium to long-term results. Since discharge from hospital after TKA is achieved increasingly quicker worldwide using FP in an increasingly younger and active patient population, the effects of FP on functional outcome in the first days after TKA become more important. The purpose of the current study was to compare FP with a regular joint care protocol (RP), with an emphasis on the first 7 days after surgery.

MATERIALS AND METHODS

A non-blinded randomized controlled clinical pilot study was performed with 25 patients assigned to a FP group and 25 patients assigned to a RP group. Primary outcome was functional outcome, clinical outcome, pain, and complications for each day in the first week after surgery. Patients were followed up to 5 years after surgery.

RESULTS

Significantly lower VAS scores for knee pain, faster Timed-Up and Go test times and more mobility on functional tests were seen on several days in the first week in the FP group compared to the RP group. Few other significant differences were found at 2, 6 weeks, and no significant differences were found at 12 weeks and 1, 2 and 5 years after surgery.

CONCLUSIONS

Fast-track protocol for primary TKA showed significantly lower knee pain scores and improved functional outcome in the first 7 days after TKA compared to a regular protocol.

Surgery performed by supervised registrars does not adversely affect medium-term functional outcomes after total knee replacement

Introduction Although total knee arthroplasty (TKA) is an index procedure for orthopaedic registrars, there is a lack of published research as to the effects of surgery when performed by supervised trainees. The aim of this study was to compare functional outcomes up to five years after primary TKA performed by consultants and trainee surgeons. Methods A retrospective analysis was conducted of prospectively collected data for 609 consecutive patients (339 female, 270 male) undergoing TKA. Patients were assessed preoperatively as well as at 18 months, three years and five years postoperatively, and American Knee Society objective knee and functional scores (AKSK and AKSF) were recorded. Results Surgery was performed by a consultant in 465 cases and a supervised trainee in 144 cases. There were no significant differences between the two groups in preoperative patient characteristics, operative time (p=0.15), transfusion rates (p=0.84), length of stay (p=0.98), manipulation under anaesthesia (p=0.69), or mortality rates at one year (p=0.73) or five years (p=0.81). Postoperatively, the median magnitude of improvement in AKSK (48 points for consultant group vs 45 points for trainee group, p=0.74) and in AKSF (both groups 15, p=0.995) was similar between the groups. AKSK and AKSF scores were similar at all timepoints up to five years following surgery, and there was no difference in the median range of motion (both groups 100°, IQR: 18°) at five years (p=0.43). Conclusions TKA performed by supervised registrars gives functional outcomes that are equivalent to consultant performed TKA, without affecting postoperative range of movement, or increasing operative time, length of stay or transfusion rates. Rates of postoperative MUA and mortality are also comparable.

Clinical Outcome of Total Knee Arthroplasty After Prior Microfracture: A Matched Cohort Study

Microfracture (MFX) is a common operation for articular cartilage lesions. Data for patients who underwent total knee arthroplasty (TKA) after previous MFX are limited. The purpose of this study was to determine the outcomes, complications, and factors that influence outcomes in patients with previous MFX compared with those without previous MFX. Between 2005 and 2014, twenty-one TKAs were performed at a single tertiary care academic institution in patients with prior history of MFX surgery. These patients were retrospectively reviewed and matched 2:1 to patients who did not undergo previous MFX (n=42). Knee Society Score (KSS) (Subjective [KSS-S] and Function [KSS-F]) and complications were documented. Mean KSS-S in the MFX group increased significantly less (52.9 to 77.6) (P<.01) compared with the control group (51.3 to 83.8) (P<.01). The MFX group also demonstrated significantly less improvement in KSS-F from 63.0 to 88.9 (P=.02), whereas the control group demonstrated improvement from 52.4 to 87.1 (P=.02). At 5 years, the failure rate was 4.8% in the MFX group and 2.4% in the control group. Multivariate analysis found that older age at TKA resulted in smaller improvement in KSS-S. Paired relationships between increased age and decreased preoperative range of motion and women with an increased body mass index negatively affected KSS-S. Survivorship was similar between groups, but patients with MFX had slightly less clinical improvement compared with a matched control group. This study suggests that underlying patient factors may limit clinical improvement compared with primary TKA. [Orthopedics. 2017; 40(3):e473-e478.].

Sports Activity after Low-contact-stress Total Knee Arthroplasty - A long term follow-up study

The purpose of this study was to provide comprehensive long-term data about sports activity levels in patients following total knee arthroplasty (TKA) and to determine the impact of pre-operative function, pain and specific performed sports on the results. 236 patients who have undergone TKA for severe osteoarthritis of the knee were asked to provide specific information regarding exercised types of sports before surgery and after at least 10 years following TKA. Pre- and postoperative function and pain were evaluated by the use of Tegner-, WOMAC- and VAS Score. After a mean of 14.9 years, a significant improvement regarding pain and function was observed. Pre-operative Tegner- and WOMAC scores revealed significant positive correlations with the post-operative Tegner-Score. Accordingly, a high percentage of patients (70.9%) stayed actively involved in sports. Nevertheless, the number of performing patients has decreased according to the sports impact. 71.3% continued practising low-impact-, 43.7% intermediate-impact sports whereas only 16.4% kept performing high impact sports. We conclude that TKA is highly effective in long-time pain reduction as well as improvement of function. Additionally, we found considerable sports activities preserved in the investigated series. However, sports activities in particular, seem to decrease according to the impact of sports.