Does Greater Knee Flexion Increase Patient Function and Satisfaction After Total Knee Arthroplasty?

The purpose of this study was to determine whether high flexion leads to improved benefits in patient satisfaction, perception, and function after total knee arthroplasty (TKA). Data were collected on 122 primary TKAs. Patients completed a Total Knee Function Questionnaire. Knees were classified as low (≤110°), mid (111°-130°), or high flexion (>130°). Correlation between knee flexion and satisfaction was not statistically significant. Increased knee flexion had a significant positive association with achievement of expectations, restoration of a “normal” knee, and functional improvement. In conclusion, although the degree of postoperative knee flexion did not affect patient satisfaction, it did influence fulfillment of expectations, functional ability, and knee perception. This suggests that increased knee flexion, particularly more than 130°, may lead to improved outcomes after TKA.     

Can a High-flexion Total Knee Arthroplasty Relieve Pain and Restore Function Without Premature Failure?

Background  

High-flexion TKA prostheses are designed to improve flexion and clinical outcomes. Increased knee flexion can increase implant loads and fixation stresses, creating concerns of premature failure. Whether these goals can be achieved without premature failures is unclear.     

Can Computer Assistance Improve the Clinical and Functional Scores in Total Knee Arthroplasty?

Background  

Surgical navigation in TKA facilitates better alignment; however, it is unclear whether improved alignment alters clinical evolution and midterm and long-term complication rates.     

How Flat Is the Tibial Osteotomy in Total Knee Arthroplasty?

BackgroundCementless total knee arthroplasty has been developed to decrease the incidence of failure in younger and more active patients. However, failures are still more common in cementless versus cemented components. It is hypothesized that this is triggered by incomplete bone-tray contact. The present study compares the final contact area of a cementless tray as a function of the initial osteotomy flatness.MethodsEight surgeons prepared 14 cadaveric knees for cementless total knee replacement using standard instrumentation. The topography of each osteotomy was captured with a laser scanner; 3-dimensional computer models of the surfaces were generated. After scanning each tibia, the surgeons implanted cementless tibial trays using a manual impactor. Each tibia was then dissected, embedded in mounting resin, and sectioned. The sectioned blocks were observed under stereomicroscopy to identify points of bone-tray contact which were incorporated into the 3-dimensional models. Maps were then generated illustrating depicting contacting and noncontacting areas.ResultsThe mean initial flatness of all specimens was 1.1 ± 0.35 mm. After impaction, 79.4% ± 0.3% of the surface had established bony contact. Of the noncontacting areas, 17.6% were within 0.3 mm of the tray. Only 2.6% of the surface was at distances reported to impede ingrowth. Noncontacting areas were typically located centrally. A trend in decreasing percent contact area with increased flatness tolerance was observed (R² = 0.605).Conclusion(1) There is an inverse correlation between the flatness of the tibial osteotomy and the percentage of the bony surface in contact with underside of the tibial tray. (2) Almost all tray-tibia contact is generated during implantation through flattening of elevated features on the tibial surface. (3) Gaps between the tray and the tibia are consistently located in the central regions of the osteotomy proximal to the medullary canal.     

Does Physical Activity Level Influence Total Hip Arthroplasty Expectations,Satisfaction, and Outcomes?

BackgroundTotal hip arthroplasty (THA) patients expect pain relief and functional improvement, including return to physical activity. Our objective was to determine the impact of patients' physical activity level on preoperative expectations and postoperative satisfaction and clinical outcomes in patients undergoing THA.MethodsUsing an institutional registry of patients undergoing THA between 2007 and 2012, we retrospectively identified patients who underwent unilateral primary THA for osteoarthritis and completed a preoperative Lower Extremity Activity Scale, Hospital for Special Surgery Hip Replacement Expectations Survey, and Hip disability and Osteoarthritis Outcome Score in addition to two-year HOOS and satisfaction evaluations. Active patients (n = 1053) were matched to inactive patients (n = 1053) by age, sex, body mass index, and comorbidities. The cohorts were compared with regard to the association of expectations with Hip disability and Osteoarthritis Outcome Score and satisfaction, the change in Lower Extremity Activity Scale level from baseline to 2 years, complications, and revision surgical procedures.ResultsSignificantly more active patients (74%) expected to be “back to normal” regarding ability to exercise and participate in sports compared with inactive patients (64%, P < .001). Overall satisfaction was similar. Higher expectations with regard to exercise and sports were associated with higher HOOS sports and recreation subdomain scores in active patients. The inactive patient group improved on baseline activity level at 2 years while the active group did not.ConclusionAt 2 years after THA, active and inactive patients were similarly satisfied and achieved comparable outcomes. Inactive patients showed a greater improvement in physical activity level from preoperative baseline than active patients. Complications and revision rates were similar.Level of EvidenceIII.     

Robotic-Assisted Total Knee Arthroplasty: What are Patients’ Perspectives,Understanding and Expectations?

BackgroundThe rate of using robotic-assisted total knee arthroplasty (RA-TKA) has increased markedly. Understanding how patients view the role of robotics during total knee arthroplasty (TKA) informs shared decision making and facilitate efforts to appropriately educate patients regarding the risks and benefits of robotic assistance.MethodsA self-administered questionnaire was completed by 440 potential TKA patients at the time of their surgery scheduling. Participants answered 25 questions regarding RA-TKA, socioeconomic factors, and their willingness to pay (WTP) for RA-TKA. Logistic regressions were used to determine if population characteristics and surgeon preferences influenced the patients’ perceptions of RA-TKA.ResultsThere were 39.7% of respondents who said that they had no knowledge regarding RA-TKA. Only 40.7% of participants had expressed a desire for RA-TKA to be used. There were 8.7% who were WTP extra for the use of RA-TKA. Participants believed that the main 3 benefits of RA-TKA compared to conventional methods were: more accurate implant placement (56.2%); better results (49.0%); and faster recovery (32.1%). The main 3 patient concerns were harm from malfunction (55.2%), reduced surgeon role in the procedure (48.1%), and lack of supportive research (28.3%). Surgeon preference of RA-TKA was associated with patient’s willingness to have RA-TKA (odds ratio 4.60, confidence interval 2.98-7.81, P < .001), and with WTP extra for RA-TKA (odds ratio 2.05, confidence interval: 1.01-4.26, P = .049).ConclusionPatient knowledge regarding RA-TKA is limited. Nonpeer-reviewed online information may make prospective TKA candidates vulnerable to misinformation and aggressive advertising. The challenge for orthopaedic surgeons is to re-establish control and reliably educate patients about the proven advantages and disadvantages of this emerging technology.     

Can Demographic Variables Accurately Predict Component Sizing in Primary Total Knee Arthroplasty?

Background

As health care reform drives providers to reduce costs and improve efficiencies without compromising patient care, preoperative planning has become imperative. The purpose of this study is to determine whether height, weight, and gender can accurately predict total knee arthroplasty (TKA) sizing.

Do Patient Expectations Influence Patient-Reported Outcomes and Satisfaction in Total Hip Arthroplasty? A Prospective,Multicenter Study

Background

The relationship between patient expectations and patient-reported outcomes (PROs) in total hip arthroplasty (THA) patients is controversial. The purpose of this study was to examine the impact of preoperative patient expectations on postoperative PROs and patient satisfaction.

What is the Quality of Online Resources About Pain Control After Total Knee Arthroplasty?

Background

With the growing opioid crisis in the United States, there has been a push to reduce the utilization of opioids in favor of multimodal analgesia options. The purpose of this study was to evaluate the quality of online resources that patients may use to learn about pain control after total knee arthroplasty (TKA).

Should Cannabinoids Be Added to Multimodal Pain Regimens After Total Hip and Knee Arthroplasty?

Background

This study investigated the effects of dronabinol on pain, nausea, and length of stay following total joint arthroplasty (TJA).

What Are the Causes of Revision Total Knee Arthroplasty in Japan?

Background

There is limited information regarding the cause of revision TKA in Asia, especially Japan. Owing to differences in patient backgrounds and lifestyles, the modes of TKA failures in Asia may differ from those in Western countries.

Questions/purposes

We therefore determined (1) causes of revision TKA in a cohort of Japanese patients with revision TKA and (2) whether patient demographic features and underlying diagnosis of primary TKA are associated with the causes of revision TKA.

Methods

We assessed all revision TKA procedures performed at five major centers in Hokkaido from 2006 to 2011 for the causes of failures. Demographic data and underlying diagnosis for index primary TKA of the revision cases were compared to those of randomly selected primary TKAs during the same period.

Results

One hundred forty revision TKAs and 4047 primary TKAs were performed at the five centers, indicating a revision burden of 3.3%. The most common cause of revision TKA was mechanical loosening (40%) followed by infection (24%), wear/osteolysis (9%), instability (9%), implant failure (6%), periprosthetic fracture (4%), and other reasons (8%). The mean age of patients with periprosthetic fracture was older (77 versus 72 years) and the male proportion in patients with infection was higher (33% versus 19%) than those of patients in the primary TKA group. There was no difference in BMI between primary TKAs and any type of revision TKA except other causes.

Conclusions

The revision burden at the five referral centers in Hokkaido was 3.3%, and the most common cause of revision TKA was mechanical loosening followed by infection. Demographic data such as age and sex might be associated with particular causes of revision TKA.     

Have Venous Thromboembolism Rates Decreased in Total Hip and Knee Arthroplasty?

BackgroundVenous thromboembolism (VTE) is a major cause of morbidity, mortality, and healthcare costs in arthroplasty patients. In an effort to reduce VTEs, numerous strategies and guidelines have been implemented, but their impact remains unclear. The purpose of this study is to compare annual trends in 30-day VTE, deep vein thrombosis (DVT), pulmonary embolism (PE), and all-cause mortality in (1) total hip arthroplasty (THA) and (2) total knee arthroplasty (TKA).MethodsThe American College of Surgeons National Surgical Quality Improvement Program (NSQIP) database identified 363,530 patients who received a TKA or THA from 2008 to 2016. Bivariate analysis was performed to assess the association between the year in which surgery was performed and demographics and comorbidities. Bimodal multivariate logistic regression models for THA and TKA were developed for 2009-2016 using 2008 as a reference.ResultsOverall incidence of VTE, DVT, PE, and mortality for THA were 0.6%, 0.4%, 0.3%, and 0.2%, respectively. Based off of multivariate regression VTE, DVT, PE, and mortality rates have shown no significant (P > .05) change from 2008 to 2016 in THA patients. Overall incidence of VTE, DVT, PE, and mortality for TKA were 1.4%, 0.9%, 0.6%, and 0.1%, respectively. Multivariate regression revealed reductions when compared to 2008 for VTEs and DVTs from 2009 to 2016 (P < .05) for TKA patients. A significant reduction in PEs (P = .002) was discovered for 2016, while no significant change was observed in mortality (P > .05).ConclusionApproximately 1 in 71 patient undergoing TKA, and 1 in 167 undergoing THA developed a VTE within 30 days after surgery. Our study demonstrated that VTE incidence rates have decreased in TKA, while remaining stable in THA over the past 8 years. Further research to determine the optimal prophylaxis algorithm that would allow for a personalized, efficacious, and safe thromboprophylaxis regimen is needed.Level of EvidenceIII.     

Computer-Assisted Total Knee Arthroplasty: Is There a Difference Between Image-Based and Imageless Techniques?

Background

Image-based and imageless computer-assisted total knee arthroplasty (CATKA) has become increasingly popular. This study aims to compare outcomes, including perioperative complications and transfusion rate, between CATKA and conventional total knee arthroplasty (TKA), as well as between image-based and imageless CATKA.