Revisiting patient satisfaction following total knee arthroplasty: a longitudinal observational study

Racial and Ethnic Disparities in Predictive Accuracy of Machine Learning Algorithms Developed Using a National Database for 30-Day Complications Following Total Joint Arthroplasty

BACKGROUND

While predictive capabilities of machine learning (ML) algorithms for hip and knee total joint arthroplasty (TJA) have been demonstrated in previous studies, their performance in racial and ethnic minority patients has not been investigated. This study aimed to assess the performance of ML algorithms in predicting 30-day complications following TJA in racial and ethnic minority patients.

METHODS

A total of 267,194 patients undergoing primary TJA between 2013 and 2020 were identified from a national outcomes database. The patient cohort was stratified according to race, with further sub-stratification into Hispanic or non-Hispanic ethnicity. There were two ML algorithms, histogram-based gradient boosting (HGB), and random forest (RF), that were modeled to predict 30-day complications following primary TJA in the overall population. They were subsequently assessed in each racial and ethnic subcohort using discrimination, calibration, accuracy, and potential clinical usefulness.

RESULTS

Both models achieved excellent (Area under the curve (AUC) > 0.8) discrimination (AUCHGB = AUCRF = 0.86), calibration, and accuracy (HGB: slope = 1.00, intercept = -0.03, Brier score = 0.12; RF: slope = 0.97, intercept = 0.02, Brier score = 0.12) in the non-Hispanic White population (N = 224,073). Discrimination decreased in the White Hispanic (N = 10,429; AUC = 0.75 to 0.76), Black (N = 25,116; AUC = 0.77), Black Hispanic (N = 240; AUC = 0.78), Asian non-Hispanic (N = 4,809; AUC = 0.78 to 0.79), and overall (N = 267,194; AUC = 0.75 to 0.76) cohorts, but remained well-calibrated. We noted the poorest model discrimination (N = 1,870; AUC = 0.67 to 0.68) and calibration in the American-Indian cohort.

CONCLUSION

The ML algorithms demonstrate an inferior predictive ability for 30-day complications following primary TJA in racial and ethnic minorities when trained on existing healthcare big data. This may be attributed to the disproportionate underrepresentation of minority groups within these databases, as demonstrated by the smaller sample sizes available to train the machine learning models. The ML models developed using smaller datasets (e.g., in racial and ethnic minorities) may not be as accurate as larger datasets, highlighting the need for equity-conscious model development.

Late Manipulation under Anesthesia after Total Knee Arthroplasty: Improved Range of Motion and a Low Complication Rate

The purpose of this study was to evaluate outcomes of late manipulation under anesthesia (MUA) for stiffness performed from ≥12 weeks to more than a year after primary total knee arthroplasty (TKA). A total of 152 patients receiving MUA ≥12 weeks after primary TKA from 2014 to 2021 were reviewed. The primary outcome measured was change in range of motion (ROM). We tracked intraoperative complications and the need for repeat MUA or open procedure for continued stiffness after initial MUA. Three subgroups were analyzed: Group 1 included 58 knees between 12 weeks and 6 months after TKA, Group 2 included 44 knees between 6 and 12 months after TKA, and Group 3 included 50 knees ≥12 months after TKA. Analysis included descriptive statistics and univariate analysis, with α <0.05. Groups 1 to 3 all significantly increased their overall ROM by 20.9, 19.2, and 22.0 degrees, respectively. All groups significantly increased their flexion and extension from preoperatively. Group 1 had one intraoperative supracondylar femur fracture (1.7%) requiring open reduction and internal fixation, and five patients required repeat MUA or open procedure (8.6%). Group 2 had no intraoperative fractures, and five patients required repeat MUA or open procedure (11.4%). Group 3 had one intraoperative tibial tubercle avulsion fracture managed conservatively (2.0%) and one repeat MUA (2.0%). Late MUA resulted in significantly improved ROM in all groups. ROM improved more as the time from index TKA increased, although statistically insignificant. Repeat MUA or open procedure rate decreased with MUA ≥12 months from TKA, although statistically insignificant. The overall intraoperative fracture risk was 1.3%.

Aetiology of patient dissatisfaction following primary total knee arthroplasty in the era of robotic-assisted technology

Aims

Patient dissatisfaction following primary total knee arthroplasty (TKA) with manual jig-based instruments has been reported to be as high as 30%. Robotic-assisted total knee arthroplasty (RA-TKA) has been increasingly used in an effort to improve patient outcomes, however there is a paucity of literature examining patient satisfaction after RA-TKA. This study aims to identify the incidence of patients who were not satisfied following RA-TKA and to determine factors associated with higher levels of dissatisfaction.

Methods

This was a retrospective review of 674 patients who underwent primary TKA between October 2016 and September 2020 with a minimum two-year follow-up. A five-point Likert satisfaction score was used to place patients into two groups: Group A were those who were very dissatisfied, dissatisfied, or neutral (Likert score 1 to 3) and Group B were those who were satisfied or very satisfied (Likert score 4 to 5). Patient demographic data, as well as preoperative and postoperative patient-reported outcome measures, were compared between groups.

Results

Overall, 45 patients (6.7%) were in Group A and 629 (93.3%) were in Group B. Group A (vs Group B) had a higher proportion of male sex (p = 0.008), preoperative chronic opioid use (p < 0.001), preoperative psychotropic medication use (p = 0.01), prior anterior cruciate ligament (ACL) reconstruction (p < 0.001), and preoperative symptomatic lumbar spine disease (p = 0.004). Group A was also younger (p = 0.023). Multivariate analysis revealed preoperative opioid use (p = 0.012), prior ACL reconstruction (p = 0.038), male sex (p = 0.006), and preoperative psychotropic medication use (p = 0.001) as independent predictive factors of patient dissatisfaction.

Conclusion

The use of RA-TKA demonstrated a high rate of patient satisfaction (629 of 674, 93.3%). Demographics for patients not satisfied following RA-TKA included: male sex, chronic opioid use, chronic psychotropic medication use, and prior ACL reconstruction. Patients in these groups should be identified preoperatively and educated on realistic expectations given their comorbid conditions.

Effect of Adding Stem Extension to a Short-Keeled Knee Implant on the Risk of Tibial Loosening: a Historical Cohort Study

BACKGROUND

Short-keeled tibial implants may be at higher risk of aseptic loosening. Stem augmentation has been suggested to improve its fixation. We aimed to assess whether this technique could decrease the loosening rate of such tibial implants.

METHODS

We retrospectively studied the knees receiving stemmed versus nonstemmed versions of a short-keeled prosthesis. A total of 932 patients undergoing total knee arthroplasty using a Persona prosthesis with >24-month follow-up (mean 53.7) were included, of whom 212 were at high risk of loosening due to osteoporosis or high body mass index (BMI). The rate of tibial aseptic loosening in high-risk patients and in the whole cohort was compared between those with and without stem extension. Multivariable analysis was conducted to identify the risk factors of loosening.

RESULTS

In the whole cohort, in 203 knees (21.8%), a cemented short stem was used, versus 729 knees (78.2%) without. The tibial implant revision rates for loosening were 2.06% and 0.99% for nonstemmed and stemmed cases, respectively (P = 0.551). When the cohort was categorized based on the loosening risk factors, the loosening risk was significantly higher in the high-risk than in the low-risk group, regardless of stem status (log-rank test = 8.1, hazard ratio = 2.17, 95% CI = 1.78, 2.57, P = 0.005). 212 patients were at high risk of loosening, due to high BMI or osteoporosis, among whom the risk of aseptic loosening was higher when a stem was not used (log-rank = 32.1, hazard ratio = 4.95, 95% CI = 4.05, 5.86, P < 0.001). In multivariate analysis, osteoporosis, BMI ≥35, and smoking were correlated with loosening.

CONCLUSION

The failure rate was markedly lower in the stemmed group of the patients at elevated risk of aseptic loosening due to osteoporosis and/or high BMI. In the entire cohort, the risk of loosening in stemmed tibial implants was similar to the nonstemmed group. The findings support a protective role for the stem in patients at high risk of failure of the cemented tibial implant.

LEVEL OF EVIDENCE

III therapeutic.

The Role of Imageless Computer-Assisted Navigation During Total Knee Arthroplasty on Femoral Component Sagittal Alignment and Outcomes

Background

While total knee arthroplasty (TKA) is highly successful, 15%-20% of patients are not satisfied postoperatively, which may be due to alignment of the TKA components. Imageless computer navigation was developed to increase implant alignment accuracy and precision, but controversy surrounds the patient benefit of this technology. The target of femoral sagittal alignment and its role in patient-reported outcomes (PROMs) after TKA using assistive technology has not been well-defined.

Methods

Femoral sagittal alignment, 30-day complications, and PROMs through 1 year were collected retrospectively from unilateral elective TKA patients who underwent surgery between July 2020 and February 2023. Two surgeons equally versed in conventional and imageless navigation techniques participated in patient record identification. Students t-tests and chi-square tests of proportion were used to compare outcomes, 30-day complications, and alignment.

Results

Completed PROMs were available for 387 patients; 181 in the computer navigation group and 206 in the conventional arthroplasty group. PROMs were statistically significantly different between groups, favoring computer navigation (P = .014 at 12 months). Lateral femoral angle measurements were greater in females who underwent TKA with computer navigation (P < .001). Of note, 14 patients in the conventional technique group returned to the emergency department within 30 days, as compared to 4 in the navigation group (P = .033).

Conclusions

PROMs are improved in the navigation group compared to the conventional technique group. Fewer patients in the navigation group returned to the emergency department. Navigation appeared to provide a small benefit compared to conventional techniques, though final lateral femoral angle was not predictive of outcomes. Additional surgical characteristics may need to be examined to determine the reasons for the differences in outcomes between these techniques.

Effect of Intravenous Zoledronic Acid on Total Knee Replacement in Patients With Symptomatic Knee Osteoarthritis and Without Severe Joint Space Narrowing: A Prespecified Secondary Analysis of a Two-Year, Multicenter, Double-Blind, Placebo-Controlled Clinical Trial

OBJECTIVE

To determine the effect of zoledronic acid (ZA) on the risk of total knee replacement (TKR) in patients with symptomatic knee osteoarthritis and without severe joint space narrowing (JSN).

METHODS

We included 222 participants (mean age 62 years, 52% female) from the two-year Zoledronic Acid for Osteoarthritis Knee Pain trial (113 received 5 mg of ZA annually and 109 received placebo) conducted between November 2013 and October 2017. Primary TKR were identified until February 22, 2022. The effect of ZA on TKR risk was evaluated using Cox proportional hazard regression models. Because the treatment effect failed the proportional hazards assumption, a time-varying coefficients analysis for treatment was conducted by splitting the study into two periods (ie, within and after two years of randomization).

RESULTS

Over a mean follow-up of seven years, 39% and 30% of participants had any TKR in the ZA and placebo groups, and 28% and 18% had TKR in the study knee, respectively. Use of ZA was associated with a higher risk of TKR in any knee (hazard ratio [HR] 4.2, 95% confidence interval [CI] 1.2-14.7) and showed a trend in the study knee (HR 6.8, 95%CI 0.9-53.9) during the trial. In the posttrial period, the risk of TKR was similar in the ZA and the placebo groups for any knee (HR 1.2, 95%CI 0.5-1.8) and the study knee (HR 1.4, 95%CI 0.5-2.2).

CONCLUSION

These results suggest that ZA is not protective against TKR in patients with symptomatic knee osteoarthritis and without severe JSN.

Randomized Placebo-Controlled Trial of 60-Day Percutaneous Peripheral Nerve Stimulation Treatment Indicates Relief of Persistent Postoperative Pain, and Improved Function After Knee Replacement

OBJECTIVES

Total knee arthroplasty (TKA) is an effective surgery for end-stage knee osteoarthritis, but chronic postoperative pain and reduced function affect up to 20% of patients who undergo such surgery. There are limited treatment options, but percutaneous peripheral nerve stimulation (PNS) is a promising nonopioid treatment option for chronic, persistent postoperative pain. The objective of the present study was to evaluate the effect of a 60-day percutaneous PNS treatment in a multicenter, randomized, double-blind, placebo-controlled trial for treating persistent postoperative pain after TKA.

MATERIALS AND METHODS

Patients with postoperative pain after knee replacement were screened for this postmarket, institutional review board-approved, prospectively registered (NCT04341948) trial. Subjects were randomized to receive either active PNS or placebo (sham) stimulation. Subjects and a designated evaluator were blinded to group assignments. Subjects in both groups underwent ultrasound-guided placement of percutaneous fine-wire coiled leads targeting the femoral and sciatic nerves on the leg with postoperative pain. Leads were indwelling for eight weeks, and the primary efficacy outcome compared the proportion of subjects in each group reporting ≥50% reduction in average pain relative to baseline during weeks five to eight. Functional outcomes (6-minute walk test; 6MWT and Western Ontario and McMaster Universities Osteoarthritis Index) and quality of life (Patient Global Impression of Change) also were evaluated at end of treatment (EOT).

RESULTS

A greater proportion of subjects in the PNS groups (60%; 12/20) than in the placebo (sham) group (24%; 5/21) responded with ≥50% pain relief relative to baseline (p = 0.028) during the primary endpoint (weeks 5-8). Subjects in the PNS group also walked a significantly greater distance at EOT than did those in the placebo (sham) group (6MWT; +47% vs -9% change from baseline; p = 0.048, n = 18 vs n = 20 completed the test, respectively). Prospective follow-up to 12 months is ongoing.

CONCLUSIONS

This study provides evidence that percutaneous PNS decreases persistent pain, which leads to improved functional outcomes after TKA at EOT.

Capability After Total Knee Arthroplasty for Osteoarthritis Is Strongly Associated With Preoperative Symptoms of Depression

BACKGROUND

Primary total knee arthroplasty (TKA) aims to improve the level of capability (ability to perform valued life activities) associated with knee osteoarthritis (OA). However, some evidence suggests a substantial proportion of patients remain dissatisfied with their outcomes after this procedure. We sought to better understand the association between mental health, specifically symptoms of depression, with postoperative outcomes. Symptoms of depression are shown to be common among orthopaedic populations in general and can be briefly and conveniently evaluated using the Patient Health Questionnaire-2 (PHQ-2) in a less burdensome manner compared with longer mental health surveys. This study assesses the association between preoperative depressive symptoms (PHQ-2) and levels of capability at 6 weeks and 6 months after TKA.

METHODS

We conducted a prospective cohort study involving 114 patients with knee OA across five clinics in California and Texas scheduled for TKA. Participants completed a preoperative PHQ-2 and Knee Injury and OA Outcome Score for Joint Replacement (KOOS JR) survey at 6 weeks and 6 months post-TKA. We analyzed these data using bivariate and multivariable regression.

RESULTS

Preoperative PHQ-2 scores were significantly associated with lower KOOS JR scores at 6 weeks and 6 months post-TKA. Latino/Hispanic race was also associated with lower KOOS JR scores at 6 weeks. The association between preoperative depressive symptoms and level of capability after TKA were more pronounced at 6 months compared with 6 weeks.

CONCLUSION

Preoperative symptoms of depression are strongly associated with reduced capability after TKA and can be screened for using the PHQ-2-a brief tool that can be feasibly incorporated into clinical workflows. User-friendly assessment of depressive symptoms can assist orthopaedic surgeons in identifying and addressing mental health at the outset during the management of knee OA.

Comparison of Patients' and Surgeons' Expectations before Shoulder Arthroplasty

Background: Patients suffering from osteoarthritis particularly complain about pain during day and night as well as loss of function. This consequently leads to impaired quality of life and therefore psychological stress. The surgical therapy of choice is joint replacement. Regarding the outcome after operation, expectations might differ between the patient and the surgeon. This can lead to dissatisfaction on both sides. This study aimed to document patients' expectations of a planned shoulder joint replacement. The results were compared with assessments made by shoulder surgeons. Methods: In total, 50 patients scheduled for operative shoulder joint replacement were included in this study, as well as 10 shoulder surgeons. Patients were requested to fill out questionnaires preoperatively to provide sociodemographic data, PROMS (Patient-Reported Outcome Measures) with regard to the pathology and their expectations about surgery in terms of pain relief, gain of range of motion, strength as well as the impact on activities of daily and professional life and sports. In addition, surgeons were asked what they thought their patients expect. Results: The most important goal to achieve for patients was to relieve daytime pain, followed by improvement of self-care and the ability to reach above shoulder level. The most important factors for patients to achieve after operation were 'pain relief' in first place, 'movement' in second and 'strength' in third. This also applied to shoulder surgeons, who ranked 'pain relief' first, followed by 'movement' and 'strength'. When patients where asked what is most important when it comes to choosing their surgeon, 68% voted for 'surgical skills', 28% for 'age/experience', followed by 'empathy', 'sympathy' and 'appearance'. For surgeons, 'age/experience' obtained rank one, 'surgical skills' was ranked second, followed by 'sympathy', 'empathy' and 'appearance'. Surgeons significantly underrated the factor 'empathy' in favor of 'sympathy'. Conclusions: This study shows that patients' expectations for shoulder joint replacement and surgeons' assessments do not differ significantly. Relief from pain and better shoulder movement were crucial for patients to achieve after operation, which was in line with surgeons' expectations. The most important factor for choosing the surgeon was 'surgical skills' for patients, while surgeons thought they would care more about 'age and experience'. This underlines that patients' expectations should be taken into account within the preoperative medical interview. This might allow an optimization of compliance of the patients and lead to a better satisfaction on both sides.

Predicting Recovery Following Total Hip and Knee Arthroplasty Using a Clustering Algorithm

Background

Recovery following total joint arthroplasty is patient-specific, yet groups of patients tend to fall into certain similar patterns of recovery. The purpose of this study was to identify and characterize recovery patterns following total hip arthroplasty (THA) and total knee arthroplasty (TKA) using patient-reported outcomes that represent distinct health domains. We hypothesized that recovery patterns could be defined and predicted using preoperative data.

Methods

Adult patients were recruited from a large, urban academic center. To model postoperative responses to THA and TKA across domains such as physical health, mental health, and joint-specific measures, we employed a longitudinal clustering algorithm that incorporates each of these health domains. The clustering algorithm from multiple health domains allows the ability to define distinct recovery trajectories, which could then be predicted from preoperative and perioperative factors using a multinomial regression.

Results

Four hundred forty-one of 1134 patients undergoing THA and 346 of 921 undergoing TKA met eligibility criteria and were used to define distinct patterns of recovery. The clustering algorithm was optimized for 3 distinct patterns of recovery that were observed in THA and TKA patients. Patients recovering from THA were divided into 3 groups: standard responders (50.8%), late mental responders (13.2%), and substandard responders (36.1%). Multivariable, multinomial regression suggested that these 3 groups had defined characteristics. Late mental responders tended to be obese (P = .05) and use more opioids (P = .01). Substandard responders had a larger number of comorbidities (P = .02) and used more opioids (P = .001). Patients recovering from TKA were divided among standard responders (55.8%), poor mental responders (24%), and poor physical responders (20.2%). Poor mental responders were more likely to be female (P = .04) and American Society of Anesthesiologists class III/IV (P = .004). Poor physical responders were more likely to be female (P = .03), younger (P = .04), American Society of Anesthesiologists III/IV (P = .04), use more opioids (P = .02), and be discharged to a nursing facility (P = .001). The THA and TKA models demonstrated areas under the curve of 0.67 and 0.72.

Conclusions

This multidomain, longitudinal clustering analysis defines 3 distinct patterns in the recovery of THA and TKA patients, with most patients in both cohorts experiencing robust improvement, while others had equally well defined yet less optimal recovery trajectories that were either delayed in recovery or failed to achieve a desired outcome. Patients in the delayed recovery and poor outcome groups were slightly different between THA and TKA. These groups of patients with similar recovery patterns were defined by patient characteristics that include potentially modifiable comorbid factors. This research suggests that there are multiple defined recovery trajectories after THA and TKA, which provides a new perspective on THA and TKA recovery.

Level of Evidence

III.

Calipered kinematic alignment restored the arithmetic hip-knee-ankle angle, achieved high satisfaction and improved clinical outcomes

PURPOSE

The purpose of this study was to determine whether unrestricted calipered kinematic alignment (KA), coupled with a medial-stabilised (MS) implant system, can reproduce the patient's constitutional alignment as per the arithmetic hip-knee-ankle (aHKA) and improve clinical outcomes.

METHODS

One-hundred and ninety-three patients received total knee arthroplasty by the senior author. To determine whether the constitutional alignment was achieved, the postoperative hip-knee-ankle (HKA) alignment was compared against the aHKA. Range of motion (ROM) was determined preoperative and postoperatively at 6 months and 2 years by measuring the active flexion and extension. Patient-Reported Outcomes Measures (PROMs) including Oxford Knee Score (OKS), Knee Injury and Osteoarthritis Outcome Score (KOOS), Forgotten Joint Score (FJS) and Visual Analogue Scale for Satisfaction were also completed. The Sports and Recreation component of KOOS was used to assess the patient's ability to return to sports and daily activities.

RESULTS

There was a strong correlation between postoperative HKA and aHKA (r = 0.7, p < 0.05). There was a significant improvement in both extension and flexion seen from as early as 6 months postoperatively, with a mean flexion of 123° ± 11° and extension of 1° ± 3° at 2 years. PROMs had significant improvements with a mean score of 42.8 ± 6.0 for the OKS and all KOOS subscales consisting of Symptoms (88.0 ± 11.7), Pain (91.4 ± 11.6), Activities of Daily Living (91.1 ± 12.4), Sports (76.8 ± 22.1) and Quality of Life (83.0 ± 19.1). The FJS had significant improvements from 6 months to 2 years of 19.9 (p < 0.05), with a mean score of 69.2 ± 26.6 at 2 years. Ninety-three percent (180 patients) were classified as 'satisfied' at the 2-year timepoint. The KOOS Sports component was completed by 64% (124 patients), whereby the mean age was younger than the noncompliant patients (67.7 ± 9.4 vs. 71.7 ± 8.2 years).

CONCLUSION

Unrestricted calipered KA can result in an alignment that closely resembles the patient's constitutional alignment, as per the aHKA. This resulted in improved knee ROM and patient satisfaction, as well as assisting younger patients to return to sports and daily activities.

LEVEL OF EVIDENCE

Level IV.

Is 80% satisfaction still the expectation in modern TKA mechanically aligned with robot assist? We think not

Several studies reported that20% of patients were unhappy with the outcome of their total knee arthroplasty (TKA). Having commenced robot assist TKA whilst maintaining the goal of implanting the prosthesis to a neutral mechanical axis, we reviewed our patients to find out if we also have a 20% rate of patients being unhappy with the outcome of their knee replacement surgery. We hypothesized that rate of patient satisfaction would be higher than 90% with robot-surgical assistant (ROSA) technique. The first 175 patients who underwent ROSA TKA were reviewed at a minimum of 1 year postoperatively. All TKAs were performed using ROSA technique with Persona cementless prosthesis aiming to restore neutral mechanical coronal alignment with flexion gap balancing. We investigated whether or not the patients were happy they had their knee replacement surgery and whether they were happy with the outcome. 165 (94%) of 175 patients, were contactable with 1 deceased and 9 uncontactable. From the 165 patients who participated in the study, 95% of patients were happy they had the surgery done and 93% were happy with the outcome of their knee replacement. A sub analysis showed that patients who had simultaneous bilateral TKA were significantly less likely to be happy than staged procedures (p < 0.05). Total knee replacement utilising robot technique with modern implants and aiming for mechanical coronal alignment of the implants to restore the mechanical axis with flexion gap balancing may result in > 90% of patients being happy with the outcome of their surgery.

Lateral subvastus approach to total knee arthroplasty: A novel surgical technique and retrospective review of 931 consecutive cases

Background

The lateral muscle-sparing approach total knee arthroplasty (TKA) has been detailed and indicated selectively for severe valgus deformities. We present the largest, to date, consecutive series of lateral subvastus TKAs and we hypothesize that preoperative alignments would demonstrate no differences in range of motion (ROM), knee society scores (KSS), kneeling ability, patient satisfaction, or complications.

Materials and methods

This retrospective study examined 931 primary TKAs in 824 patients performed through the lateral subvastus approach with one to two years follow-up. All primary TKAs performed between July 2020 and February 2022 were included. We used descriptive statistics, chi-squares, and analysis of variance (ANOVA) to examine the cohort. Significance was set to p < .05.

Results

Patient's ROM significantly improved by six weeks, (1-117°, P < .05) with continued improvement by one-year, (0-121, P < .05) with no significant differences in alignment in extension, (P = .142) or flexion, (P = .253). There were also no significant differences in alignment in KSS scores at six-weeks, (P = .635), three-months, (P = .829), six-months, (P = .836), one-year, (P = .641) or two-years, (P = .776). There were no significant differences in kneeling ability, (P = .563), and 85% of patients reported being able to kneel. There were no differences in patient satisfaction, (P=.436), and 90% of patients reported being satisfied. There was a low 8% complication rate in this cohort. Neutral and varus knees were less likely than valgus knees to develop deep vein thrombosis (DVT; P < .05) or have a medial collateral ligament (MCL) injury (P < .05).

Conclusions

Patients with varus, valgus, and neutral knees had similar outcomes when using a lateral subvastus approach to TKA in ROM and KSS that were stable over two years with similar kneeling ability and satisfaction. There was a low incidence of complications with neutral and varus knees at the lowest risk. A lateral subvastus approach to TKA can be safe and effective for all knee deformities.

The Early Clinical Outcomes Following Unrestricted Caliper Verified Kinematic Alignment Using a Medial Stabilized Design Total Knee Arthroplasty With a Cruciate Retaining Insert

Background

Although various total knee arthroplasty (TKA) implant designs are widely used, the ideal TKA design is yet to be agreed upon. Although the benefits of cruciate-retaining (CR) TKA and medial stabilized (MS) TKA have been reported in literature, the early clinical outcomes of an MS TKA with CR inserts have not been reported. This study aims to report on the patient-reported clinical and radiological outcomes of MS-TKA combined with a CR insert.

Methods

A prospective single-surgeon series evaluated the clinical- and patient-reported outcomes of 115 patients implanted with GMK Sphere CR. Patient outcomes were assessed with the Oxford Knee Score, Knee Injury and Osteoarthritis Outcome Scores (KOOS), Forgotten Joint Score, and Visual Analogue Scale for Satisfaction. Radiological assessment for alignment along with active flexion and extension were also assessed.

Results

Improvement in all scores was observed between the preoperative and 1-year follow-up timepoints, with statistical significance seen for Oxford Knee Score as well as KOOS Symptoms, Pain, Sport, quality of life, and activities of daily living subscales. The mean active flexion between the preoperative and both postoperative timepoints at 6 months and 1 year was also statistically significant (P = .021 and P = .001).

Conclusions

MS-TKA with a CR insert can facilitate symptom relief and improve overall function of the knee after surgery. Both the patient and clinical outcomes were comparable to 1-year outcomes utilizing other MS-TKA designs and were superior to those at 1-year follow-up following implantation of CR-TKA. Most notability, the KOOS symptoms and sports score were higher for the MS-TKA with a CR insert than for an MS-TKA design.

Early application of extracorporeal shock wave therapy improves pain control and functional scores in patients undergoing total knee arthroplasty: a randomized controlled trial

PURPOSE

The use of biophysical stimuli produced by extracorporeal shock wave therapy (ESWT) can improve the rehabilitation treatment of patients undergoing total knee arthroplasty (TKA). The aim of our study is to evaluate the short-term efficacy of early postoperative ESWT in combination with physiotherapy in terms of pain reduction and motor function recovery of patients undergoing TKA and compare it with conventional physiotherapy treatment.

METHODS

Fifty-six patients undergoing TKA were enrolled in the study from January 2019 to February 2020. Patients received two sessions of physiotherapy daily, with (experimental group) or without (control group) four sessions of ESWT within seven days after surgery. Patients were prospectively evaluated at baseline and at post-operative day two and seven. Assessment included active knee range of motion (aROM), timed up and go (TUG) test, visual analogue scale (VAS) for pain, and Borg scale.

RESULTS

Fifty patients completed the study. Both treatments proved to be effective in reducing pain and improving the knee range of motion and functional scores at seven days after surgery: the aROM in the ESWT group was 36.8 ± 11.0 grades (p < 0.001), while in control group was 19.8 ± 7.8 grades (p < 0.001). TUG, VAS, and BORG scores showed a similar trend. Comparative analysis revealed superior clinical results for the experimental group in all the outcomes, in particular aROM (96.0 ± 5.40 vs. 81.20 ± 11.01, p < 0.001) and TUG test (17.4 ± 5.61 vs. 21.24 ± 5.88, p < 0.001), at day seven after surgery.

CONCLUSION

Early application of ESWT in addition to physiotherapy can positively influence the rehabilitation process after TKA. The treatment proved to be well tolerated and safe. Preliminary results demonstrated better pain control and functional scores compared to physiotherapy alone.

Fulfilment of patients' mandatory expectations are crucial for satisfaction: a study amongst 352 patients after total knee arthroplasty (TKA)

PURPOSE

Patient satisfaction with the results of their total knee arthroplasty (TKA) is one of the primary goals of this elective procedure. Furthermore, the association between the fulfilment of patients' expectations and their satisfaction is well known. The aim of this study was to identify the key expectations of patients awaiting a TKA, evaluate their fulfilment, and compare the outcomes between very and not fully satisfied patients.

METHODS

A prospective cohort study of patients with knee OA scheduled for primary TKA was performed. Pre- and one-year postoperatively patient-reported outcome measures (PROMs) were assessed. Expectations and their fulfilment were evaluated via a questionnaire encompassing 31 expectations. Preoperatively, expectations were indicated as mandatory, desirable and not important. Postoperatively, fulfilment was rated as exceeded, fulfilled, partially or not fulfilled, and not applicable. Satisfaction with the results of TKA was measured with a numeric rating scale (NRS) of 0-10. Discrimination between not fully satisfied and very satisfied patients was set at ≥ 8, as has been proposed recently. To identify independent predictors of this discrimination, a multivariate logistic regression analysis was performed.

RESULTS

Complete data sets of 352 patients were analysed. A set of 17 key expectations was identified. Relief of knee pain was fulfilled the most, and improvement of physical function was fulfilled the least. When asked about overall fulfilled expectations, 40% of patients rated them as exceeded, 34% as fulfilled and 26% as less fulfilled than expected. Not fully satisfied patients showed significantly lower PROMs pre- and postoperatively and less fulfilled key expectations. Higher numbers of exceeded and fulfilled mandatory expectations, higher overall fulfilment and better range of motion (ROM) were significant predictors for satisfaction ≥ 8.

CONCLUSION

Patients' expectations of TKA outcomes were high with equal emphasis on knee-related and general health-related aspects. Their fulfilment was positively associated with satisfaction. Surgeons should ask patients about mandatory expectations for successful TKA and counsel them about the likelihood of their fulfilment to avoid unrealistic expectations.

LEVEL OF EVIDENCE

II.

Influence of kinematic alignment on femorotibial kinematics in medial stabilized TKA design compared to mechanical alignment

INTRODUCTION

Worldwide more and more primary knee replacements are being performed. Kinematic alignment (KA) as one of many methods of surgical alignment has been shown to have a significant impact on kinematics and function. The aim of the present study was to compare KA and mechanical alignment (MA) with regard to femorotibial kinematics.

MATERIALS AND METHODS

Eight fresh frozen human specimens were tested on a knee rig during active knee flexion from 30 to 130°. Within the same specimen a medial stabilized (MS) implant design was used first with KA and then with MA.

RESULTS

The femorotibial kinematics showed more internal rotation of the tibia in KA compared to MA. At the same time, there was a larger medial rotation point in KA. Both alignment methods showed femoral rollback over the knee bend.

CONCLUSION

Relating to an increased internal rotation and a more precise medial pivot point, it can be concluded that KA combined with a MS implant design may partially support the reproduction of physiological knee joint mechanics.

Relationships Between Preoperative Mental Health and Improvements in Patient-Reported Outcomes After Total Hip and Knee Arthroplasty

BACKGROUND

Poor preoperative mental health has been associated with worse outcomes after total hip (THA) and total knee arthroplasty (TKA). To fully understand these relationships, we assessed post-THA and post-TKA improvements in patient-reported mental and joint health by preoperative mental health groups.

METHODS

Elective cases (367 THA, 462 TKA) were subgrouped by low (<25th percentile), middle (25th-74th), and high (≥75th) preoperative mental health, using Veterans RAND 12-Item Health Survey Mental Component Summary (MCS) scores. In each subgroup, we assessed the relationship between preoperative MCS and 1-year postoperative change in mental and joint health. Pairwise comparisons and multivariable regression models were applied for THA and TKA separately.

RESULTS

Median postoperative mental health change was +14.0 points for the low-MCS THA group, +11.1 low-TKA, +2.0 middle-THA and TKA, -4.0 high-THA, and -4.9 high-TKA (between-group differences P < .001). All MCS groups had improved median joint health scores, without significant between-group differences. Preoperative mental health was negatively associated with mental health improvements in all groups (B = -0.94 - -0.68, P < .001-P = .01) but with improvements in joint health only in the low-THA group (B = -0.74, P = .02). Improvements in mental and joint health were positively associated for low and middle (B = 0.61-0.87, P < .001), but not for high-MCS groups, with this relationship differing for the low versus high group.

CONCLUSION

Patients who have low preoperative mental health experienced greater postoperative mental health improvement and similar joint health improvement compared to patients who have high preoperative mental health. Findings can guide subgroup-targeted surgical decision-making and preoperative counseling.

A review of quality-of-life in elderly osteoarthritis

INTRODUCTION

Osteoarthritis (OA) is the commonest joint disease in the world. Although aging is not invariably associated with OA, aging of the musculoskeletal system increases susceptibility to OA. Pain and reduced function due to OA, negatively impact health-related quality of life (HRQoL) in the elderly.

AREAS COVERED

We searched PubMed and Google Scholar with search term "osteoarthritis' combined with terms 'elderly' 'ageing' 'healthrelated quality of life' 'burden' "prevalence 'hip osteoarthritis' 'knee osteoarthritis' 'hand osteoarthritis' to identify relevant articles. This article discusses the global impact and joint-specific burden due to OA and the challenges in assessment of HRQoL in elderly with OA. We further describe some HRQoL determinants that particularly impact elderly persons with OA. These determinants include physical activity, falls, psychosocial consequences, sarcopaenia, sexual health, and incontinence. The usefulness of physical performance measures, as an adjunct to assessing HRQoL is explored. The review concludes by outlining strategies to improve HRQoL.

EXPERT OPINION

Assessment of HRQoL in elderly with OA is mandatory if effective interventions/treatment are to be instituted. But existent HRQoL assessments have shortcomings when used in elderly§. It is recommended that determinants of QoL which are unique to the elderly, be examined with greater detail and weightage in future studies.

A multi-disciplinary program for opioid sparse arthroplasty results in reduced long-term opioid consumption: a four year prospective study

INTRODUCTION

The current opioid epidemic poses patient safety and economic burdens to healthcare systems worldwide. Postoperative prescriptions of opioids contribute, with reported opioid prescription rates following arthroplasty as high as 89%. In this multi-centre prospective study, an opioid sparing protocol was implemented for patients undergoing knee or hip arthroplasty. The primary outcome is to report our patient outcomes in the context of this protocol, and to examine the rate of opioid prescription on discharge from our hospitals following joint arthroplasty surgery. This is possibly associated with the efficacy of the newly implemented Arthroplasty Patient Care Protocol.

METHODS

Over three years, patients underwent perioperative education with the expectation to be opioid-free after surgery. Intraoperative regional analgesia, early postoperative mobilisation and multimodal analgesia were mandatory. Long-term opioid medication use was monitored and PROMs (Oxford Knee/Hip Score (OKS/OHS), EQ-5D-5 L) were evaluated pre-operatively, and at 6 weeks, 6 months and 1 year postoperatively. Primary and secondary outcomes were opiate use and PROMs at different time points.

RESULTS

A total of 1,444 patients participated. Two (0.2%) knee patients used opioids to one year. Zero hip patients used opioids postoperatively at any time point after six weeks (p < 0.0001). The OKS and EQ-5D-5 L both improved for knee patients from 16 (12-22) pre-operatively to 35 (27-43) at 1 year postoperatively, and 70 (60-80) preoperatively to 80 (70-90) at 1 year postoperatively (p < 0.0001). The OHS and EQ-5D-5 L both improved for hip patients from 12 (8-19) preoperatively to 44 (36-47) at 1 year postoperatively, and 65 (50-75) preoperatively to 85 (75-90) at 1 year postoperatively (p < 0.0001). Satisfaction improved between all pre- and postoperative time points for both knee and hip patients (p < 0.0001).

CONCLUSIONS

Knee and hip arthroplasty patients receiving a peri-operative education program can effectively and satisfactorily be managed without long-term opioids when coupled with multimodal perioperative management, making this a valuable approach to reduce chronic opioid use.

Patient acceptable symptom state (PASS): thresholds for the EQ-5D-5L and Oxford hip and knee scores for patients with total hip and knee replacement

PURPOSE

To define patient acceptable symptom state (PASS) cut-off values for the EQ-5D-5L and Oxford hip (OHS) and knee (OKS) scores 6 and 12 months after total hip (THR) or knee (TKR) replacement. To compare PASS cut-off values for the EQ-5D-5L scored using: (1) the Canadian value set, (2) the crosswalk value set, and (3) the equal weighted Level Sum Score (LSS).

METHODS

We mailed questionnaires to consecutive patients following surgeon referral for primary THR or TKR and at 6 and 12 months post-surgery. Patient reported outcome measures (PROMs) were the EQ-5D-5L, the OHS, and OKS. We assessed PASS cut-off values for PROMs using percentile and ROC methods, with the Youden Index.

RESULTS

Five hundred forty-two surgical patients (mean age, 64 years, 57% female, 49% THR) completed baseline and 12-month questionnaires. 89% of THR and 81% of TKR patients rated PASS as acceptable at 12 months. PASS cut-off values for THR for the EQ-5D-5L (Canadian) were 0.85 (percentile) and 0.84 (Youden) at 12 months. Cut-off values were similar for the LSS (0.85 and 0.85) and lower for the crosswalk value set (0.74 and 0.73), respectively. EQ-5D-5L cut-off values for TKR were Canadian, 0.77 (Percentile) and 0.78 (Youden), LSS, 0.75 and 0.80, and crosswalk, 0.67 and 0.74, respectively. Cut-off values 6 and 12 months post-surgery ranged from 38 to 39 for the OHS, and 28 to 36 for the OKS (range 0 worst to 48 best).

CONCLUSION

PASS cut-off values for the EQ-5D-5L and Oxford scores varied, not only between methods and timing of assessment, but also by different EQ-5D-5L value sets, which vary between countries. Because of this variation, PASS cut-off values are not necessarily generalizable to other populations of TJR patients. We advise caution in interpreting PROMs when using EQ-5D-5L PASS cut-off values developed in different countries. A standardization of methods is needed before published cut-off values can be used with confidence in other populations.

Comparing Analgesia on an As-Needed Basis to Traditional Intravenous Patient-Controlled Analgesia Within Fast-Track Orthopedic Procedures: A Randomized Controlled Trial

BACKGROUND

The aim was to determine if the use of intravenous patient-controlled analgesia (IVPCA) in a fast-track joint replacement program is associated with increased use of perioperative opioid consumption and increased length of hospital stay.

DESIGN

A prospective, double-blind, randomized controlled trial.

SETTINGS

Academic hospital.

PARTICIPANTS/SUBJECTS

A total of 80 patients aged 18-85 years, with body mass index (BMI) 18-40, undergoing elective total knee arthroplasty were recruited.

METHODS

Pre-operatively, patients received gabapentin, celecoxib, and acetaminophen. Peri-operatively, patients received spinal anesthesia with morphine and fentanyl, and periarticular local anesthetic administration by the surgeon. Postoperatively, 80 patients were randomized by a computer-generated sequence into IVPCA group (group A, n = 40) and non-IVPCA group (group B, n = 40).

RESULTS

The primary outcome was 48-hour postoperative opioid consumption and length of hospital stay. Secondary outcomes included side effects of opioids, patient satisfaction, and pain scores. There was no significant difference within 48-hour postoperative opioid consumption (median 61.3 vs. 87.5, p = .181) and length of hospital stay (median 49.8 hours vs. 49.5 hours; p = .89) between the two groups. Also, there was no significant difference in patient satisfaction (median 5 in both groups), pain scores, and opioid-related side effects.

CONCLUSIONS

IVPCA was associated with nonsignificant reduction in opioid exposure in elective total knee arthroplasty surgery within 48 hours. Neither group was superior in terms of length of hospital stay, opioid related side-effects, pain scores, and patient satisfaction.

Early Outcomes of Dual-Pivot Total Knee Replacement Compared to an Ultracongruent Design

Background

With a quest to optimize outcomes, there have been significant advancements in modern designs of total knee implants, attempting to mimic the natural knee motion and feel. One such new design reproducing the medial and lateral knee pivot is a dual-pivot (DP) knee. In the present study, we endeavored to compare the performance of the DP knee vis-a-vis an ultracongruent (UC) Knee design.

Methods

This prospective cohort study was performed in a joint replacement center of a tertiary care military hospital. We enrolled 50 patients each in the DP knee group and the UC knee group and assessed knee flexion, patient-reported outcome (new Knee Society Score [nKSS]), patient performance (Delaware Osteoarthritis Profile Score), and function (Forgotten Joint Score [FJS]) at 2 years of follow-up.

Results

The nKSS was similar in the two groups. In the DP group, patients had significantly better improvement in the stair climb test (p = 0.026). In the UC group, timed up and go test was significantly better (p = 0.004). The gain in knee flexion was similar in the two groups: 26.3° ± 23.3° in the DP group and 27.5° ± 27.5° in the UC group (p = 0.930). Return to activity as judged by 2-year FJS was similar in both groups (p = 0.687).

Conclusions

Our study showed that the DP knee design had similar knee function to the UC knee. The DP knee design had significantly better stair climbing ability, whereas getting up from chair was better in the UC knee design. With comparable patient-reported outcome and possible differences in patient performance in terms of day-to-day activities, any future trial should focus on comparing patient performance.

Many Patients With Persistent Pain 1 Year After TKA Report Improvement by 5 to 7 Years: A Mixed-methods Study

BACKGROUND

Approximately 20% of patients report pain 12 months after TKA. No studies have investigated patients' experiences of living with persistent postsurgical pain 5 to 7 years after TKA by combining a qualitative and quantitative methodology.

QUESTION/PURPOSE

In a mixed-methods study, we explored patients' experiences of living with persistent pain up to 7 years after primary TKA. We asked: In a subgroup analysis of patients who reported persistent pain 1 year after TKA surgery, how do patients live with persistent pain at the 5- to 7-year postoperative timepoint?

METHODS

This follow-up study was part of a longitudinal study of pain, symptoms, and health-related quality of life in patients who underwent TKA for osteoarthritis. The present study targeted a subgroup of patients (22% [45 of 202]) identified in the longitudinal study who reported no improvement in pain interference with walking at 12 months after surgery. Inclusion criteria were: all 31 patients in this subgroup who attended their 5-year follow-up at the hospital and lived within a 2-hour drive from the hospital. Eight patients declined or were unable to participate due to illness or death. Hence, the final sample consisted of 23 patients (13 women and 10 men). The participants' mean age at surgery was 66 ± 10 years. There were no differences in sociodemographic baseline data between the 23 included and the 22 excluded participants. A mixed-methods approach was employed, in which the quantitative data were followed up and investigated with qualitative interviews. Instruments used were the Brief Pain Inventory preoperatively, 12 months, and 5 years after surgery, as well as a semistructured interview guide. The individual interviews were conducted at one timepoint 5 to 7 years postsurgery to capture how pain was experienced at that timepoint. The interviews were audiorecorded, transcribed, and analyzed using qualitative content analysis. Meaning units were identified, condensed, and sorted into subthemes that were interpreted and abstracted into themes, guided by the research question. With a small sample, the quantitative analysis focused on descriptive statistics and nonparametric statistics when comparing demographics of included and nonincluded patients. In addition, two multivariate mixed models for repeated measures were employed to estimate within-patient and between-patient variations as well as to assess the effect of time on the pain outcomes.

RESULTS

Pain with walking decreased from 12 months to 5 years postoperatively (estimated mean score 7 versus 4, difference of means -3 [95% CI -5 to -2]; p < 0.001). Pain with daily activity decreased from 12 months to 5 years postoperatively (estimated mean score 6 versus 3, difference of means -3 [95% CI -4 to -1]; p < 0.001). Pain intensity (average pain) decreased from 12 months to 5 years postoperatively (estimated mean score 5 versus 4, difference of means -1 [95% CI -3 to 0]; p = 0.03). The results are presented as point estimates rounded up to whole numbers. The qualitative data analysis yielded three themes: persistent limitations after TKA, regained wellness over time, and complexity in physical challenges. Intermittent pain with certain movements resulted in limitations with some activities in everyday life and seemed to persist beyond 5 years. Multiple painful body sites and presence of comorbidities seemed to interfere with regained wellness over time.

CONCLUSION

In this subgroup of patients experiencing postsurgical persistent pain 12 months after primary TKA, persistent postsurgical pain still limited certain activities for the participants, although pain seemed to be less influential in their everyday lives after 5 years to 7 years. Clinicians may use these findings to inform and guide patients with delayed improvements in pain into more realistic expectations for recovery, rehabilitation, and strategies for coping with pain and impaired function. However, it is imperative to rule out other reasons for pain in patients reporting pain 12 months and longer after surgery and to be attentive of possible changes in pain over time.

LEVEL OF EVIDENCE

Level III, therapeutic study.

What matters to patients following total knee arthroplasty? A grounded theory of adapting to a knee replacement

Background

Globally the volume of total knee arthroplasty (TKA) is on the rise, reflecting aging populations, an associated increase in treatment of osteoarthritis, and a desire for improved quality of life. There is evidence that as high as 15 to 20% of patients are not satisfied with their TKA results and efforts need to be made to improve these rates. This study set out to identify what patients consider important when reflecting on TKA satisfaction, to pave the way to identifying service transformation opportunities that will enhance patient-centred care and satisfaction with this procedure.

Methods

Twenty-seven TKA recipients were recruited in the province of British Columbia, Canada. Semi-structured interviews were conducted about participants’ experience and satisfaction with TKA, three to four years post-surgery. Grounded theory was employed to analyze participants’ stories about what was front of mind when they reflected on satisfaction with their new knee.

Results

Participants described their post-TKA knee in terms its adequacy: how it felt and worked, and how it matched their pre-surgical expectations. The central element of their stories was the process of adapting, which gave rise to their perceptions of adequacy. Adapting comprises the patient experience of physically integrating and cognitively accepting their new knee. Patterns of adapting reflect the level of the new knee’s achieved adequacy and the straightforwardness of the adapting process.

Discussion

The conceptualization of adequacy and the process of adapting allow a patient-centred understanding of what patients experience following TKA. For participants who did not readily achieve the adequacy they had anticipated, the challenges they experienced during adapting dominated their stories. Participants’ adapting stories afford key insights into how the health care system could adjust to better support TKA patients, and improve rates of satisfaction with this procedure.

Conclusions

The process of adapting lends itself to system intervention in support of enhanced post-TKA outcomes and satisfaction. These interventions could include the development of a care model including long-term clinical support for patients whose knees do not achieve desired results on schedule, and collaborating with patients to set and manage reasonable expectations about how their post-TKA knee will feel and function.

Health care costs after total knee arthroplasty for satisfied and dissatisfied patients

BACKGROUND

Evidence suggests that up to 21% of patients are dissatisfied after total knee arthroplasty (TKA), but the link between dissatisfaction and use of health care resources is unknown. The objective of this study was to compare costs after TKA between satisfied and dissatisfied patients.

METHODS

This was a secondary analysis of a randomized clinical trial among patients who underwent primary TKA at our institution between 2015 and 2018. We estimated rates of satisfaction with pain relief and with return to function 1 year postoperatively. Patients prospectively reported use of health care resources 6 weeks, and 3, 6, 9 and 12 months after surgery. We compared costs between satisfied and dissatisfied patients from a public payer and a societal perspective.

RESULTS

We included 156 patients in our analysis, of whom 42 (26.9%) were dissatisfied with pain, and 57 (36.5%) were dissatisfied with function. There was no significant difference in costs between patients dissatisfied with pain or function compared to satisfied patients from a health care payer perspective. From a societal perspective, patients dissatisfied with pain incurred a mean cost of $21 156.18, compared to $13 453.84 for satisfied patients (mean difference $7702.34, 95% confidence interval [CI] -89.43 to 15 494.11). Similarly, patients dissatisfied with function incurred a mean cost of $19 007.70, compared to $13 523.83 for those who were satisfied (mean difference $5483.87, 95% CI -526.34 to 11 494.10).

CONCLUSION

Dissatisfied patients incurred greater costs than satisfied patients during the first year after TKA. The results justify further evaluation of factors contributing to patient satisfaction that may help to reduce the economic burden of TKA.

A Surgeon That Switched to Unrestricted Kinematic Alignment with Manual Instruments Has a Short Learning Curve and Comparable Resection Accuracy and Outcomes to Those of an Experienced Surgeon

After starting an orthopedic practice, a surgeon with a fellowship in mechanically aligned (MA) TKA initiated this study to characterize their learning curve after they switched to unrestricted kinematic alignment (KA) TKA using manual instruments. Accordingly, the present study determined for the inexperienced (IE) surgeon the number of cases required to achieve consistent femoral resections and operating times, and whether the femoral resection accuracy, patient-reported outcome measures (PROMs), and component alignment were different from an experienced (E) surgeon. This prospective cohort study analyzed the IE surgeon’s first 30 TKAs, all performed with KA, and 30 consecutive KA TKAs performed by an E surgeon. The resection accuracy or deviation was the calipered thickness of the distal and posterior medial and lateral femoral resections minus the planned resection thickness, which was the thickness of the corresponding condyle of the femoral component, minus 2 mm for cartilage wear, and 1 mm for the kerf of the blade. Independent observers recorded the femoral resection thickness, operative times, PROMs, and alignment. For each femoral resection, the deviation between three groups of patients containing ten consecutive KA TKAs, was either insignificant (p = 0.695 to 1.000) or within the 0.5 mm resolution of the caliper, which indicated no learning curve. More than three groups were needed to determine the learning curve for the operative time; however, the IE surgeon’s procedure dropped to 77 min for the last 10 patients, which was 20 min longer than the E surgeon. The resection deviations of the IE and E surgeon were comparable, except for the posterolateral femoral resection, which the IE surgeon under-resected by a mean of −0.8 mm (p < 0.0001). At a mean follow-up of 9 and 17 months, the Forgotten Joint Score, Oxford Knee Score, KOOS, and the alignment of the components and limbs were not different between the IE and E surgeon (p ≥ 0.6994). A surgeon that switches to unrestricted KA with manual instruments can determine their learning curve by computing the deviation of the distal and posterior femoral resections from the planned resection. Based on the present study, an IE surgeon could have resection accuracy, post-operative patient outcomes, and component alignment comparable to an E surgeon.

Using a patella reduced technique while balancing a TKA results in restored physiological strain in the collateral ligaments: an ex vivo kinematic analysis

INTRODUCTION

Poor soft tissue balance in total knee arthroplasty (TKA) often results in patient dissatisfaction and reduced joint longevity. Patella-in-place balancing (PIPB) is a novel technique which aims to restore native collateral ligament behavior without collateral ligament release, while restoring post-operative patellar position. This study aimed to assess the effectiveness of this novel technique through a detailed ex vivo biomechanical analysis by comparing post-TKA tibiofemoral kinematics and collateral ligament behavior to the native condition.

MATERIALS AND METHODS

Eight fresh-frozen cadaveric legs (89.2 ± 6 years) were tested on a validated dynamic knee simulator, following computed tomography imaging. Specimens were subjected to passive flexion (10-120°), squatting (35-100°), and varus/valgus laxity testing (10 Nm at 0°, 30°, 60°, 90° flexion). An optical motion capture system recorded markers affixed rigidly to the femur, tibia, and patella, while digital extensometers longitudinally affixed to the superficial medial collateral ligament (MCL) and lateral collateral ligament (LCL) collected synchronized strain data. Following native testing, a Stryker Triathlon CR TKA (Stryker, MI, USA) was performed on each specimen and the identical testing protocol was repeated. Statistical analyses were performed using a linear mixed model for functional motor tasks, while Wilcoxon signed-rank test was used for laxity tests (p < 0.05).

RESULTS

Postoperative laxity was lower than the native condition at all flexion angles while post-operative ligament strain was lowered only for MCL at 30° (p = 0.017) and 60° (p = 0.011). Postoperative femoral rollback patterns were comparable to the native condition in passive flexion but demonstrated a more pronounced medial pivot during squatting.

CONCLUSIONS

Balancing a TKA with the PIPB technique resulted in reduced joint laxity, while restoring collateral ligament strains. The technique also seemed to restore kinematics and strains, especially in passive flexion.

Patient and Implant Performance of Satisfied and Dissatisfied Total Knee Arthroplasty Patients

BACKGROUND

Implant migration and altered kinematics have been thought to impact patient-reported outcome measures (PROMs) and postoperative patient satisfaction. In this study comparing satisfied and dissatisfied total knee arthroplasty (TKA) patients, we hypothesized that dissatisfied patients will have greater continuous implant migration and that there will be differences in joint kinematics, objective functional measurements, and PROMs between satisfied and dissatisfied patients.

METHODS

The Knee Society Score Satisfaction Subsection questions regarding satisfaction with function were used at least 6 months postoperation to split 50 patients into satisfied and dissatisfied groups. Patients underwent radiostereometric analysis to evaluate migration and kinematics. A wearable sensor system obtained objective measurements of patient function during timed up and go tests. PROMs were recorded preoperation and postoperation.

RESULTS

No statistically significant differences were found in migration between satisfied and dissatisfied groups. Statistical kinematic differences existed in lateral anteroposterior contact location at 20° and 40° of flexion at 1 year, where the dissatisfied group had more anteriorly located lateral contact. No statistically significant differences were present in objective functional measurements. Satisfied and dissatisfied groups had differing PROMs at 4 timepoints or greater for each questionnaire.

CONCLUSIONS

No differences were found in tibial component migration or objectively measured function between satisfied and dissatisfied patients. Functionally dissatisfied patients had more anteriorly positioned contact on the lateral condyle in early flexion and reported more pain and unmet expectations. These findings suggest that improving the functional satisfaction of TKA requires restoration of kinematics in early flexion and management of patient's pain and expectations.

Restricted kinematic alignment leads to uncompromised osseointegration of cementless total knee arthroplasty

PURPOSE

While kinematic alignment (KA) total knee arthroplasty (TKA) with cemented implants has been shown to provide equivalent or better results than mechanical alignment, its combination with cementless fixation has not yet been documented. The purpose of this study is to report (1) revision rate and causes, (2) clinical results based on patient report outcome measures (PROMs), and (3) radiological signs of implant dysfunction in patients with an uncemented TKA implanted with restricted KA (rKA), after a minimum follow-up of 2 years.

METHODS

This study included the first 100 consecutive uncemented cruciate retaining TKAs implanted between November 2015 and February 2018 by a single surgeon following rKA principles. At last follow-up, all adverse events and PROMs assessed by WOMAC, KOOS, and FJS scores were documented. Radiographic evaluation was performed to identify signs of implant loosening.

RESULTS

After a mean follow-up of 49 months (32, 60), no implant revision was performed for aseptic loosening. Three revisions were performed: one for malalignment, one for a deep infection, and one for instability. The mean WOMAC score was 20.1 (0-79, 21.3), the mean KOOS score was 71.5 (19.0-96.6, 19.8), and the mean FJS score was 65.9 (0-100, 29.6). No radiological evidence of implant aseptic loosening or osteolysis was identified.

CONCLUSION

This study shows that in 99% of our cases, rKA combined with the tested cementless TKA implant allowed for adequate secondary fixation and good functional outcomes in the short term. Favourable mid- to long-term implant survivorship is anticipated.

LEVEL OF EVIDENCE

III.

The Learning Curve of Reaching the Planned Limb Alignment in Robotic-Arm-Assisted Total Knee Arthroplasty

Evidence on the learning curve associated with robotic-arm-assisted total knee arthroplasty (ra-TKA) is scarce and mostly based on operative time. Thus, the objective of this study was to assess a surgeon's learning experience based on accuracy to reach planned limb alignment and its impact on surgical-characteristics, limb-alignment, and perioperative-outcomes. A retrospective chart review was conducted on a consecutive series of 204 primary ra-TKAs (patients), performed by a single surgeon in a single institution (3/7/2018-to-6/18/2019). Cumulative summation control sequential analysis was used for the assessment of the learning curve using accuracy of reaching the planned limb alignment establishing that surgeries had an initial-learning-phase, followed by a second-consolidation-phase. Baseline demographics, operative/tourniquet times, prosthesis type, and limb alignment were compared between these two phases. Length of stay, discharge disposition, complications, reoperation/readmission (90 days), and total morphine equivalents (TMEs) prescribed were compared between phases. Independent sample t-tests, and chi-squared analyses were performed. ra-TKA demonstrated a learning curve of 110 cases for reaching planned limb alignment (p = 0.012). Robotic experience resulted in significantly more proportion of knees in neutral-axis postoperatively (p = 0.035) and significant reduction in TMEs prescribed (p = 0.04). The mean operative and tourniquet time were found to be significantly lower in second-phase versus the first-phase (p for both < 0.0001). ra-TKA has a significant learning curve in clinical practice. A surgeon can reach the planned limb alignment with increased accuracy over time (110-cases). Progressive robotic learning and associated operative time efficiency can lead to significantly lower opioid consumption in patients undergoing TKA.

Effect of Counseling on Quality of Life and Self-Care Agency for Patients Who are Scheduled for Total Knee Replacement

This study aims to determine the effect of counseling on quality of life and self-care agency for patients who are scheduled for total knee replacement (TKR). The study has a quantitative and quasi-experimental design with a control group. The patients in the control group (n = 40) received routine care. Face-to-face and telephone counseling was offered to individuals in the intervention group (n = 39). The data was collected at face-to-face interviews by using a patient characteristics form, Quality of Life Scale, and Self-Care Agency Scale. The scores for quality of life and self-care agency in the 6th to 8th and 14th to 16th weeks after surgery were very significantly higher in the intervention group than in the control group (p < .001). This study shows that counseling given by the nurse increases the quality of life and self-care agency of patients undergoing TKR.

The effectiveness of exercise therapy and education plus cognitive behavioral therapy, alone or in combination with total knee arthroplasty in patients with knee osteoarthritis - study protocol for the MultiKnee trial

Background

One in five patients report chronic pain following total knee arthroplasty (TKA) and are considered non-improvers. Psychological interventions such as cognitive behavioral therapy (CBT), combined with exercise therapy and education may contribute to reduced pain an improved function both for patients with OA or after TKA surgery, but the evidence for the effectiveness of such interventions is scarce. This randomized controlled trial with three arms will compare the clinical effectiveness of patient education and exercise therapy combined with internet-delivered CBT (iCBT), evaluated either as a non-surgical treatment choice or in combination with TKA, in comparison to usual treatment with TKA in patients with knee OA who are considered candidates for TKA surgery.

Methods

The study, conducted in three orthopaedic centers in Norway will include 282 patients between ages 18 and 80, eligible for TKA. Patients will be randomized to receive the exercise therapy + iCBT, either alone or in combination with TKA, or to a control group who will undergo conventional TKA and usual care physiotherapy following surgery. The exercise therapy will include 24 one hour sessions over 12 weeks led by a physiotherapist. The iCBT program will be delivered in ten modules. The physiotherapists will receive theoretical and practical training to advise and mentor the patients during the iCBT program. The primary outcome will be change from baseline to 12 months on the pain sub-scale from the Knee Injury and Osteoarthritis Outcome Score (KOOS). Secondary outcomes include the remaining 4 sub-scales from the KOOS (symptoms, function in daily living, function in sports and recreation, and knee-related quality of life), EQ-5D-5L, the Pain Catastrophizing Scale, the 30-s sit-to-stand test, 40-m walking test and ActiGraph activity measures. A cost-utility analysis will be performed using QALYs derived from the EQ-5D-5L and registry data.

Discussion

This is the first randomized controlled trial to investigate the effectiveness of exercise therapy and iCBT with or without TKA, to optimize outcomes for TKA patients. Findings from this trial will contribute to evidence-based personalized treatment recommendations for a large proportion of OA patients who currently lack an effective treatment option.

Trial registration

Clinicaltrials.gov: NCT03771430. Registered: Dec 11, 2018.

A randomized controlled trial comparing functional outcomes for navigated kinematically aligned total knee arthroplasty versus navigated mechanically aligned total knee arthroplasty : the MaKKRO trial

Aims

Nearly 99,000 total knee arthroplasties (TKAs) are performed in UK annually. Despite plenty of research, the satisfaction rate of this surgery is around 80%. One of the important intraoperative factors affecting the outcome is alignment. The relationship between joint obliquity and functional outcomes is not well understood. Therefore, a study is required to investigate and compare the effects of two types of alignment (mechanical and kinematic) on functional outcomes and range of motion.

Methods

The aim of the study is to compare navigated kinematically aligned TKAs (KA TKAs) with navigated mechanically aligned TKA (MA TKA) in terms of function and ROM. We aim to recruit a total of 96 patients in the trial. The patients will be recruited from clinics of various consultants working in the trust after screening them for eligibility criteria and obtaining their informed consent to participate in this study. Randomization will be done prior to surgery by a software. The primary outcome measure will be the Knee injury and Osteoarthritis Outcome Score The secondary outcome measures include Oxford Knee Score, ROM, EuroQol five-dimension questionnaire, EuroQol visual analogue scale, 12-Item Short-Form Health Survey (SF-12), and Forgotten Joint Score. The scores will be calculated preoperatively and then at six weeks, six months, and one year after surgery. The scores will undergo a statistical analysis.

Discussion

There is no clear evidence on the best alignment for a knee arthroplasty. This randomized controlled trial will test the null hypothesis that navigated KA TKAs do not perform better than navigated MA TKAs.

Cite this article: Bone Jt Open 2021;2(11):945–950.

Use of a Tourniquet and Spinal Anesthesia Increases Satisfactory Outcomes After Total Knee Arthroplasty: A Randomized Study

BACKGROUND

Total knee arthroplasty (TKA) is usually performed successfully with or without a tourniquet and under spinal anesthesia (SA) or general anesthesia (GA). However, 10% to 34% of patients experience dissatisfaction and pain after TKA. We aimed to compare the effects of tourniquet use and SA or GA on TKA outcomes.

METHODS

We randomly assigned 404 patients to 4 study groups: SA without a tourniquet (NT/SA), SA with a tourniquet (T/SA), GA without a tourniquet (NT/GA), and GA with a tourniquet (T/GA). The primary outcome was the change in the Oxford Knee Score (OKS) at 1 year postoperatively. Secondary outcomes included a satisfactory TKA outcome assessed using the OKS minimal important change (MIC) and OKS patient acceptable symptom state (PASS), adverse events, and quality of life using the 15-dimensional health-related quality of life tool.

RESULTS

At 1 year, the OKS was obtained for 381 patients. In the 2-group comparisons, the tourniquet did not affect the OKS improvement. The SA group had more substantial improvement in the OKS than the GA group (16.21 compared with 14.08 a mean difference of 2.13; 95% confidence interval [CI], 0.55 to 3.71; p = 0.008). In the 4-group comparisons, the T/SA group had more substantial improvements in the OKS than the NT/GA group (16.87 compared with 13.65, a mean difference of 3.2; 95% CI, 0.28 to 6.17; p = 0.026). The SA group reached the OKS MIC more frequently than the GA group (91.7% compared with 81.7%; odds ratio [OR] = 2.49 [95% CI, 1.32 to 4.69]; p = 0.005). The SA group also reached the OKS PASS more frequently than the GA group (86.0% compared with 75.7%; OR = 2.00 [95% CI, 1.18 to 3.39]; p = 0.010). The T/SA group had significantly more patients reaching the OKS MIC than the NT/GA group (95.7% compared with 79.6%; p = 0.005) and more patients reaching the OKS PASS than the NT/GA group (92.6% compared with 74.5%; p = 0.004). No differences were seen with respect to adverse events in any comparisons.

CONCLUSIONS

The tourniquet had no detrimental effects on the outcomes of TKA. SA had a positive effect on the OKS. The use of SA combined with a tourniquet resulted in the best improvement in OKS and the highest proportion of satisfactory outcomes with TKA.

LEVEL OF EVIDENCE

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

Hip and Knee Replacement Patients' Experiences With an Orthopaedic Patient Navigator: A Qualitative Study

Hip and knee replacement surgery is common, yet more than 10% of patients who undergo total hip replacement (THR) and total knee replacement (TKR) report postsurgery dissatisfaction. Recommendations for improving patient experience after total joint replacement surgery include increasing support to patients, including having a patient navigator available to patients before and after surgery. This article reports on THR and TKR patients' experiences of using an orthopaedic patient navigator. We employed qualitative description to understand THR and TKR patients' experiences of interacting with an orthopaedic patient navigator in a community teaching hospital. Telephone interviews were conducted with 15 purposefully selected total joint replacement patients (TKR: n = 11; THR: n = 4) who had at least one contact with the navigator. Interview transcripts were analyzed using thematic analysis. Patients described receiving physical support services, emotional support services, informational support services, and care coordination services from the patient navigator. All interactions with the patient navigator were positive. Knowing the patient navigator was available for any future concerns also provided indirect benefits of reassurance, comfort, and security. Patients described these direct and indirect benefits as potentially having long-lasting and resilient positive effects. An orthopaedic patient navigator can have a positive impact on patients' THR and TKR experience and fill gaps in support identified in earlier studies. Addressing patients' complex and varied care needs is well suited to a clinical nurse specialist in the role. Investing in an orthopaedic patient navigator provides reassurance to patients that their needs are a priority and will be addressed in a timely manner.

Patient Satisfaction Following Primary Total Knee Arthroplasty: Contributing Factors

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

Reliability and validity of the Hebrew version of the forgotten joint score for assessing the outcomes of total knee arthroplasty

Background

This prospective study aimed to assess the reliability and validity of the Hebrew version of the forgotten joint score-12 in patients undergoing total knee arthroplasty, because it is going to be used in the Hebrew-speaking populations in Israel.

Methods

The English version of forgotten joint score-12 was translated into Hebrew version by using the standard procedures and in collaboration with its authors. The consecutive patients who had undergone total knee arthroplasty in a single hospital were asked to fill out the Hebrew version of forgotten joint score-12, Oxford knee score, Short Form 12, and visual analog scale. A random subgroup of 60 patients were then asked to fill out a second Hebrew version of forgotten joint score-12 at a minimum of 2-week interval. The reliability was assessed in terms of internal consistency, test-retest reliability and split-half reliability. The validity was measured in terms of the outcomes as mentioned above.

Results

A total of 102 patients participated in the study. The Hebrew version of forgotten joint score-12 showed high reliability. The internal consistency was excellent (Cronbachs’ α = 0.943) and test-retest reliability was high (Intraclass correlation = 0.97). The forgotten joint scores were correlated with the Oxford knee score, Short Form 12, and visual analog scale (r = 0.86, r = 0.72, and r=-0.8, respectively), indicating a high validity.

Conclusions

The Hebrew version of forgotten joint score-12 has excellent reliability, excellent test-retest reliability and good validity. It can be safely used for assessing outcomes of TKA.

Does the Use of Intraoperative Technology Yield Superior Patient Outcomes Following Total Knee Arthroplasty?

INTRODUCTION

There is debate regarding whether the use of computer-assisted technology, such as navigation and robotics, has any benefit on outcomes or patient-reported outcome measures (PROMs) following total knee arthroplasty (TKA). This study aims to report on the association between intraoperative use of technology and outcomes in patients who underwent primary TKA.

METHODS

We retrospectively reviewed 7096 patients who underwent primary TKA from 2016-2020. Patients were stratified depending on the technology utilized: navigation, robotics, or no technology. Patient demographics, clinical data, Forgotten Joint Score-12 (FJS), and Knee injury and Osteoarthritis Outcome Score for Joint Replacement (KOOS, JR) were collected at various time points up to 1-year follow-up. Demographic differences were assessed with chi-square and ANOVA. Clinical data and PROMs were compared using univariate ANCOVA, controlling for demographic differences.

RESULTS

A total of 287(4%) navigation, 367(5%) robotics, and 6442(91%) manual cases were included. Surgical-time significantly differed between the three groups (113.33 vs 117.44 vs 102.11; P < .001). Discharge disposition significantly differed between the three groups (P < .001), with more manual TKA patients discharged to a skilled nursing facility (12% vs 8% vs 15%; P < .001) than those who had technology utilized. FJS scores did not statistically differ at three-months (P = .067) and one-year (P = .221). We found significant statistical differences in three-month KOOS, JR scores (59.48 vs 60.10 vs 63.64; P = .001); however, one-year scores did not statistically differ between all groups (P = .320).

CONCLUSION

This study demonstrates shorter operative-time in cases with no utilization of technology and clinically similar PROMs associated with TKAs performed between all modalities. While the use of technology may aid surgeons, it has not currently translated to better short-term outcomes.

LEVEL III EVIDENCE

Retrospective Cohort.

Outcomes of total joint arthroplasty in patients with depression: A systematic review

BACKGROUND

Depression has been implicated as a poor predictor of outcomes after total joint arthroplasty (TJA) of the lower extremity in some studies. We aimed to determine whether depression as a comorbidity affects the TJA outcomes and whether pain reduction associated with successful TJA alters depressive symptoms.

METHODS

A search of PUBMED was performed using keywords "depression", "arthroplasty", "depressive disorder", and "outcomes." All English studies published over the last ten years were considered for inclusion. Quantitative and qualitative analysis was then performed on the data.

RESULTS

Thirty articles met inclusion criteria (16 retrospective, 14 prospective). Three showed that depressed patients were at higher risk for readmission. Two reported that depressed patients had higher likelihood of non-home discharge after TJA compared to non-depressed patients. Four noted that depressed patients incur higher hospitalization costs than non-depressed patients. Ten suggest depression is a predictor of poor patient-reported outcome measures, pain, and satisfaction after TJA. Five suggested the gains depressed patients experience in functional outcome scores after TJA are similar to gains experienced by patients without depression. Another eight suggested that TJA improves not only function and pain but also depressive symptoms in patients with depression.

CONCLUSION

The results of this review show that depression increases the risk of persistent pain, dissatisfaction, and complications after TJA. Additionally, depressed patients may incur higher costs than non-depressed patients undergoing TJA and may have worse preoperative and postoperative patient reported outcome measures (PROMs). However, the gains in function that depressed patients experience after TJA are equivalent to gains experienced by non-depressed patients and depressed patients may experience improvement in their depressive symptoms after TJA. Patient selection for TJA is critical and counseling regarding increased risk for complications is crucial in depressed patients undergoing TJA.

Oral administration of prednisone effectively reduces subacute pain after total knee arthroplasty

INTRODUCTION

Controlling the pain after TKA has always been our research focus. Dexamethasone has a significant effect in controlling acute pain following TKA. We hypothesis oral administration of prednisone could alleviate post-TKA subacute pain.

METHODS

This was a prospective, randomized controlled trial dividing patients into prednisone group and control group. Routine analgesic regimens included injection of cocktail mixture intraoperatively, oral celecoxib and tramadol postoperatively. Patients in prednisone group received oral administration of prednisone (10mg, qd, from the first day postoperatively, for 2 weeks). VAS was applied for evaluating pain with ambulation (PWA) and pain at rest (PAR). Follow-up was performed for about three months. The primary end-points were PWA and PAR; secondary end-points were postoperative daily celecoxib use and tramadol use.

RESULTS

A total of 49 patients were enrolled in prednisone group and control group, respectively. VAS of PWA was lower in prednisone group on the 7^th, 14^th and 28^th (p=0.05) day after TKA than that in the control group. Meanwhile, VAS of PAR was lower in prednisone group on the postoperative 14^th and 28^th day (p=0.05) than that in the control group.

CONCLUSIONS

Continuous oral administration of 10mg prednisone for 14 days after TKA effectively alleviates subacute pain (including PWA and PAR) and reduces postoperative consumption of analgesics.

LEVEL OF EVIDENCE

II; low power randomized trial.

Use of Fulcrum Positioning as a Balancing Tool During Total Knee Arthroplasty on a Robotic Platform

Total knee arthroplasty is a common procedure performed to improve pain and dysfunction attributed to arthritis, yet postoperative patient dissatisfaction rates remain relatively high. Patient satisfaction and outcomes have been linked to successful joint gap balancing in the coronal and sagittal planes intraoperatively. In previously described balancing techniques, the fulcrum used for alignment changes is customarily centered on the intramedullary axis generating symmetric changes in medial and lateral gaps. We propose a novel technique in the literature that, with the use of robotic-arm assisted technology or similar systems, allows manipulation of the fulcrum center of rotation during pre-resection planning and intraoperative gap establishment before bony cuts to asymmetrically influence medial and lateral, flexion and extension gaps to aid in balancing during total knee arthroplasty.

A clinical review of robotic navigation in total knee arthroplasty: historical systems to modern design

Robotic-assisted total knee arthroplasty (RA-TKA) has shown improved reproducibility and precision in mechanical alignment restoration, with improvement in early functional outcomes and 90-day episode of care cost savings compared to conventional TKA in some studies. However, its value is still to be determined.Current studies of RA-TKA systems are limited by short-term follow-up and significant heterogeneity of the available systems.In today's paradigm shift towards an increased emphasis on quality of care while curtailing costs, providing value-based care is the primary goal for healthcare systems and clinicians. As robotic technology continues to develop, longer-term studies evaluating implant survivorship and complications will determine whether the initial capital is offset by improved outcomes.Future studies will have to determine the value of RA-TKA based on longer-term survivorships, patient-reported outcome measures, functional outcomes, and patient satisfaction measures. Cite this article: EFORT Open Rev 2021;6:252-269. DOI: 10.1302/2058-5241.6.200071.

Secondary Patellar Resurfacing in TKA: A Combined Analysis of Registry Data and Biomechanical Testing

The German Arthroplasty registry (EPRD) has shown that different prosthesis systems have different rates of secondary patellar resurfacing: four years after implantation, the posterior-stabilized (PS) Vega prosthesis has a 3.2% risk of secondary patellar resurfacing compared to the cruciate-retaining (CR) Columbus prosthesis at 1.0% (both Aesculap AG, Tuttlingen, Germany). We hypothesized that PS implants have increased retropatellar pressure and a decreased retropatellar contact area compared to a CR design, which may lead to an increased likelihood of secondary patellar resurfacing. Eight fresh frozen specimens (cohort 1) were tested with an established knee rig. In addition, a possible influence of the registry-based patient collective (cohort 2) was investigated. No significant differences were found in patient data–cohort 2-(sex, age). A generally lower number of PS system cases is noteworthy. No significant increased patella pressure could be detected with the PS design, but a lower contact area was observed (cohort 1). Lower quadriceps force (100°–130° flexion), increased anterior movement of the tibia (rollback), greater external tilt of the patella, and increasing facet pressure in the Vega PS design indicate a multifactorial cause for a higher rate of secondary resurfacing which was found in the EPRD patient cohort and might be related to the PS’ principle function.

Infrapatellar Fat Pad Resection or Preservation during Total Knee Arthroplasty: A Systematic Review

Considerations of how to improve postoperative outcomes for total knee arthroplasty (TKA) have included preservation of the infrapatellar fat pad (IPFP). Although the IPFP is commonly resected during TKA procedures, there is controversy regarding whether resection or preservation should be implemented, and how this influences outcomes. Therefore, the purpose of this systematic review was to evaluate how IPFP resection and preservation impacts postoperative flexion, pain, Insall-Salvati Ratio (ISR), Knee Society Score (KSS), patellar tendon length (PTL), and satisfaction in primary TKA. PubMed, EBSCO host, and SCOPUS were queried to retrieve all reports evaluating IPFP resection or preservation during TKA, which resulted into 488 studies. Two reviewers independently reviewed these articles for eligibility based on pre-established inclusion and exclusion criteria. Eleven studies were identified for final analysis, which reported on 11,996 cases. Patient demographics, type of surgical intervention, follow-up duration, and clinical outcome measures were collected and analyzed. Complete resection was implemented in 3,723 cases (31%), partial resection in 5,458 cases (45.5%), and preservation of the IPFP in 2,815 cases (23.5%). Clinical outcome measures included PTL (5 studies), knee flexion (4 studies), pain (6 studies), KSS (3 studies), ISR (3 studies), and patient satisfaction (1 study). No differences were found following IPFP resection for patient satisfaction (p = 0.98), ISR (p > 0.05), and KSS (p > 0.05). There was mixed evidence for PTL, pain, and knee flexion following IPFP resection versus preservation. Studies of shorter follow-up intervals suggested improved pain following resection, while reports of longer follow-up times indicated that resection resulted in increased pain. Given the mixed data available from the current literature, we were unable to conclude that one surgical technique can definitively be considered superior over the other. More extensive research, including randomized controlled trials, is required to better elucidate potential differences between the surgical handling choices. Future studies should focus on patient conditions in which one technique would be best indicated to establish guidelines for best surgical outcomes in those patients.

Recommendations for Patients with High Return to Sports Expectations after TKA Remain Controversial

(1) Background: Improved surgical techniques and implants in total knee arthroplasty (TKA) have led to broader indications for surgical interventions of osteoarthritis of the knee. There is a growing young and active patient subgroup with high return to sports (RTS) expectations after TKA. The current lack of evidence regarding RTS capacity in this patient cohort, requires the consolidation of experts' opinions and experiences to address the special needs among these patients. The aim of this study was to assess current expert opinions in regard to preoperative patient assessment, surgical technique and decision-making and patient counseling for these patients. (2) Methods: We performed a survey among surgeons specialized in arthroplasty with a questionnaire designed to assess current recommendations, surgical techniques, and implant preferences as well as patient counseling in patients with high expectations for RTS after TKA. (3) Results: The majority of surgeons are in favor of return to low-impact sports after TKA within 3 to 6 months. Some even recommend return to high-impact sports. Despite improvement of surgical techniques and implants, we observed no clear preference for a single surgical technique or implant specification in active patients. (4) Conclusions: Current evidence for sports-associated complications after TKA is scarce. Despite a growing array of surgical techniques and implants, the available literature is still controversial with no single surgical technique or TKA design distinguishing itself clearly from others. Surgeons' recommendations are mostly based on their experience and training. Nonetheless, we observed growing faith in modern implants with some surgeons even recommending high-impact sports after TKA.