Compared to other cementless designs, collared metadiaphyseal-filling femoral stems are associated with a lower risk of revision and periprosthetic femoral fracture after total hip arthroplasty (THA) in patients ≥ 65 years. However, it is unclear how these designs compare to cemented femoral stems. We utilized the American Joint Replacement Registry (AJRR) to examine the risk of revision comparing cementless collared metadiaphyseal-filling versus cemented femoral stem designs.

Data from 2012 to 2021 was analyzed in patients ≥ 65 years, linked to Centers for Medicare and Medicaid data. We identified 79,022 primary THAs, stratified into two groups: cementless collared metadiaphyseal-filling stems (n = 61,854) and cemented fixation (n = 17,168). Inverse-probability-of-treatment-weighting (IPTW) cause-specific Cox proportional hazard models were used to evaluate the risks of all-cause revision and revision for periprosthetic femoral fracture, aseptic loosening, dislocation, and infection.

Compared to cemented stems, cementless collared metadiaphyseal-filling stems showed a lower risk of all-cause revision (hazard ratio [HR] 0.46, 95% confidence interval [CI] 0.38 to 0.56, P < 0.001), aseptic loosening (HR 0.35, CI 0.22 to 0.57, P < 0.001), dislocation (HR 0.39, CI 0.26 to 0.58, P < 0.001), and infection (HR 0.53, CI 0.36 to 0.78, P = 0.001). There was no difference in periprosthetic femoral fracture risk (HR 0.80, CI 0.45 to 1.42, P = 0.44).

In this cohort of patients undergoing primary THA, cementless collared metadiaphyseal-filling stems were associated with decreased risk of all-cause revision, revision for aseptic loosening, dislocation, and infection, but there was no difference in periprosthetic femoral fracture risk compared to cemented stems. Further study of cementless collared metadiaphyseal-filling designs compared to cemented fixation is warranted as there may be benefits of decreased revision risk with cementless fixation.

The rise in the adoption of outpatient arthroplasty has been attributed to its cost-effectiveness, although safety concerns persist. In this meta-analysis, we compare inpatient and outpatient joint arthroplasty with a primary focus on readmission and complication rates, using exclusively high-quality prospective data. Cost-effectiveness was used as a secondary outcome measure.

A literature search was performed in Medline, Embase and Cochrane Library from inception to October 2023. A predefined strategy was used to conduct a systematic review and meta-analysis. Twelve studies were deemed eligible for inclusion. These were critically appraised using RoB analysis and MINORS criteria. Overall readmission rate, readmission rate for THA, readmission rate for TKA, complication rate and cost-analysis were selected as outcomes of interest. Forest plots were extracted using RevMan 5.3.5 software.

The twelve studies included 2470 patients, of which 1052 were outpatients and 1418 inpatient subjects undergoing arthroplasty. Forest plot analysis showed no significant difference in safety outcomes (readmission and complication rates). However, there were significantly lower costs in the outpatient group compared to the inpatient group. The results of the analysis were; overall readmission rate (Odds ratio 0.66; P= 0.29; I2=18%), readmission rate in THA (odds ratio 0.62; P=0.10; I2=51%), readmission rate in TKA (odds ratio 0.67; P=0.56; I2=0%), overall complication rate (odds ratio 0.77; P=0.12; I2=38%) and cost analysis (RR -2.88; P<0.00001; I2= 93%).

This meta-analysis demonstrates that outpatient total joint arthroplasty (TJA) is a safe option, when compared to inpatient surgery. However, it is clear that further prospective studies and long-term randomized clinical data are necessary for a more comprehensive understanding.

Flexion instability (FI) after total knee arthroplasty (TKA) is a leading cause of early failure and is typically associated with increased early flexion, pain, swelling, and subjective instability. However, there is a subset of patients who have symptomatic flexion instability with concomitant arthrofibrosis (FI+A). This study compared outcomes in revision TKA cases performed for isolated FI to those performed for FI+A.

A retrospective review was performed on 115 patients who were revised for FI and 20 patients who were revised for FI+A. The surgical technique emphasized the established principles of tibial slope reduction, optimizing posterior femoral condylar offset, appropriate implant rotation, and modest joint line elevation. Clinical data and patient-reported outcome measures (PROMs) were evaluated. The two groups did not differ by demographics (P ≥ 0.207), mean follow-up (P = 0.462), or comorbidities (P ≥ 0.358); however, the FI group had a higher prevalence of uncontrolled depression (28 versus 5%, P = 0.026), although it was not associated with outcomes (P ≥ 0.434).

The two groups did not differ by radiographic metrics (P ≥ 0.117) or PROMs at the latest follow-up or in the change from pre-revision baseline PROMs (P ≥ 0.186). The FI+A group had a greater increase in knee range of motion (ROM) from the pre-revision baseline compared to the FI group (22.5 versus 2.2 degrees, P = 0.015). However, the FI group obtained a higher absolute post-revision ROM (116 versus 103 degrees, P = 0.016).

This study demonstrated no difference in outcomes after revision TKA comparing patients who were revised for FI+A to those revised for isolated FI. However, the FI+A group gained a clinically relevant improvement in post-revision ROM and benefited from revision TKA. Further study is warranted to understand the challenging and often multifactorial diagnosis of FI with concomitant arthrofibrosis.

III.

This study reports the outcome of a modern total knee arthroplasty design using a cementless tibial baseplate compared to the full-cemented version.

Consecutive cohorts with 12-month follow-up were evaluated. Patients receiving a cementless tibial baseplate were compared to those who received a cemented tibial component. Endpoints included revision rates and reason for revision, patient-reported outcome measures (PROMs) using the Oxford Knee Score (OKS), and progressive radiolucency. Retrieval analysis was performed for the revised cases. Pearson correlation analysis and multiple regression analysis were used.

A total of nine knees (7%) from the cementless cohort were revised, all due to aseptic loosened baseplate at a mean follow-up of 10.4 months (3 to 19), whereas the incidence of aseptic loosening of the cemented tibial baseplate was significantly lower at 0.5% (3/534; p < 0.001). The cemented cohort PROMs outperformed the cementless baseplate group at both 12 months' follow-up and the improvement from baseline (mean OKS 40.4 (SD 6.8) vs 38.5 (SD 8.1); p = 0.006; mean ΔOKS 18.8 (SD 9.0) vs 15.5 (SD 12.8); p < 0.001). There were no significant differences between the groups in the occurrence of new radiolucency at 12 months (p = 0.325). An elevated BMI was the only factor to correlate (r = -0.195) with worse values of ΔOKS (p = 0.048) in the cementless cohort. The multiple regression analysis determined that an increased BMI was the single independent predictor for aseptic loosening (p = 0.024) for the knees with a cementless tibial baseplate. Retrieval analysis suggested failed osseointegration.

In our cohort, there was a significantly higher incidence of aseptic loosening and worse PROMs at one year for the cementless tibial baseplate. An increased BMI may be an independent risk factor for aseptic loosening and inferior PROMs.

Elective primary total hip and total knee arthroplasty (collectively, total joint arthroplasties [TJAs]) are commonly performed procedures that can reduce pain and improve function. TJAs are generally safe, but complications can occur. Although historically performed as inpatient procedures, TJAs are increasingly being performed in the outpatient setting. We sought to develop a scientifically acceptable cross-setting measure for evaluating care quality across inpatient and outpatient settings.

Using Medicare administrative claims and enrollment data for qualifying TJA patients, we respecified the Centers for Medicare & Medicaid Services (CMS) inpatient-only risk-standardized TJA complications measure to assess complication rates following elective primary TJAs performed in an inpatient or outpatient setting. We aligned inpatient and outpatient coding practices and used hierarchical logistic regression to calculate hospital-specific, risk-standardized complication rates (RSCRs). Lower rates correspond to better quality. Using accepted approaches for CMS measures, we tested measure reliability and vetted key measure decisions with patient and provider input.

A single combined model including the procedure setting as a risk variable produced the highest discrimination (C-statistic for a single combined model with a setting indicator: 0.664, C-statistic for the inpatient-only model: 0.651, C-statistic for the outpatient-only model: 0.638). Among the 2,747 hospitals with at least 25 TJAs, the mean RSCR (using the combined model with a setting indicator) was 2.91% (median RSCR: 2.85%; interquartile range: 2.59% to 3.18%). The median odds ratio for complication occurrence at a higher-risk hospital compared with a lower-risk hospital was 1.33.

We respecified a measure to assess hospital inpatient or outpatient TJA performance and evaluated the reliability and validity of the measure. The findings showed variation in hospital-level complication rates across settings as indicated by this measure, supporting the feasibility of evaluating hospital performance using a more representative population than inpatient TJAs alone.

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

Tranexamic acid (TXA) is considered a potential therapeutic approach to mitigate postoperative inflammatory responses; however, its anti-inflammatory effects remain controversial. This study conducts a systematic review and meta-analysis of randomized controlled trials aiming to investigate the efficacy of multi-dose TXA in exerting anti-inflammatory effects in hip and knee arthroplasty.

We identified potential relevant literature evaluating the anti-inflammatory effects of TXA in patients undergoing hip and knee arthroplasty from PubMed, Embase, and the Cochrane Library. Meta-analysis was performed using RevMan 5.3.

Nine randomized controlled studies met the inclusion criteria. Meta-analysis results indicated that, compared with lower doses of TXA, multi-dose TXA significantly reduced the inflammatory markers IL-6 and CRP in patients undergoing hip and knee arthroplasty and shortened the length of hospital stay, with statistically significant results. Nonsignificant differences were found in the incidence of thromboembolic events.

Based on the current evidence, our results indicate that multi-dose TXA effectively reduces postoperative inflammatory responses in patients undergoing hip and knee arthroplasty. This anti-inflammatory effect is dose-dependent and is accompanied by a reduction in the length of hospital stay. Nonetheless, further high-quality, multicenter, large-sample-size randomized controlled trials are needed to confirm the anti-inflammatory effects of TXA.

Conflicting evidence leaves surgeons without clarity on the association of elevated body mass index (BMI) with the risk of mechanical loosening after total knee arthroplasty (TKA). This investigation examined the associated risk of mechanical loosening following TKA based on BMI.

We analyzed American Joint Replacement Registry data in patients aged 65 years or more from January 2012 to March 2022 who had a minimum of 2-year follow-up linked to supplemental Centers for Medicare and Medicaid data. We identified primary TKAs and excluded those with hybrid or reverse hybrid fixation, missing component data, highly constrained implants, and augments. A secondary analysis evaluated supplemental tibial stem fixation. Patients were stratified into two groups: those who had an elevated BMI more than 35 (n = 50,557) and patients who had a BMI less than 35 (n = 148,573). Cumulative Incident Function curves and cause-specific Cox models evaluated the risk of revision for mechanical loosening, adjusting for sex, age, cruciate-retaining versus posterior-stabilized femoral design, cemented versus cementless fixation, patellar resurfacing, and Charlson Comorbidity Index.

Adjusted hazard ratios (HRs) demonstrated no difference in associated risk for mechanical loosening for elevated BMI patients (HR: 0.99; 95% confidence interval [CI]: 0.97 to 1.01; P = 0.32). The Cumulative Incident Function curves showed no difference in the risk of mechanical loosening across all time points. An additional 2,956 cases were identified with supplemental tibial stem fixation; there was no difference in associated risk for mechanical loosening for elevated BMI patients with supplemental fixation (HR: 1.14; 95% CI: 0.07 to 18.21; P = 0.93).

Patients who had an elevated BMI had no associated risk for mechanical loosening following TKA with a minimum 2-year follow-up. Additional tibial stem fixation was not associated with the risk of mechanical loosening for elevated BMI patients. Further investigation is essential to discern other potentially modifiable etiologies for the risk of mechanical loosening.

Therapeutic Level III.

Background/Objectives: Total knee arthroplasty (TKA) is the gold-standard treatment for advanced knee arthritis, offering pain relief and improved joint function. However, tibial component malalignment, malrotation, and improper biomechanical loading remain critical factors contributing to implant failure, instability, and revision surgeries. This review systematically examines the impact of biomechanical loading on the tibial insert following primary TKA, with a focus on alignment, posterior tibial slope (PTS), and load distribution. Methods: A systematic literature search was conducted across the PubMed, Google Scholar, and Web of Science databases following the PRISMA guidelines. Studies investigating the effects of tibial component alignment, varus/valgus deviations, PTS, and load distribution on tibial inserts post-TKA were included. Seven studies meeting the inclusion criteria were analyzed and described narratively. Results: The reviewed studies highlighted that varus and valgus malalignment significantly alter tibiofemoral contact pressures and ligament strains, increasing the risk of aseptic loosening and implant failure. Excessive PTS was associated with posterior femoral translation, altered ligament tension, and increased contact stresses on polyethylene (PE) inserts. Kinematically aligned TKA demonstrated reduced tibial force imbalances and improved functional outcomes compared to mechanically aligned TKA. Computational and cadaveric studies revealed that even minor malalignments (e.g., 3° varus or valgus) can cause significant biomechanical changes. Conclusions: Biomechanical loading on tibial inserts after primary TKA is highly sensitive to the alignment and PTS. Optimal alignment and controlled biomechanical forces are essential. Kinematically aligned TKA has shown promising effects, preventing aseptic loosening and ensuring long-term implant survival. Further in vivo studies are needed to validate these findings and optimize surgical techniques.

Infection is one of the main complications of hip and knee arthroplasties. Topical application vancomycin to prevent postoperative infections is efficient in spine surgery, and is spreading in prosthetic surgery. However, its clinical relevance and safety are still under debate. Thus, we conducted the present study to (1) assess whether topical vancomycin reduces peri-prosthetic infection rate, and (2) investigate its influence on surgical wound complications.

Our hypothesis was that topical administration of diluted vancomycin during arthroplasty would reduce infection rate within the first postoperative year.

In total, 1900 hip and knee arthroplasties were performed between 2014 and 2021 in a single hospital. From July 2018 and December 2021, 910 prostheses were implanted with intra-articular instillation of vancomycin and tranexamic acid. From November 2014 to June 2018, 990 prostheses were set up without vancomycin. During a follow-up of minimum 12 months, we reported periprosthetic infections occurring during the first postoperative year, as well as vancomycin-induced general or cutaneous complications.

We observed periprosthetic infections in 9/990 cases (0.91%) of the control group and 10/910 cases (1.1%) of the vancomycin group (p = 0.82). In parallel, we observed wound complications (erythema, seroma, hematoma, dehiscence and delay in wound healing) in 19/990 (1.9%) and 10/910 cases (1.1%) of the control and vancomycin group, respectively (p = 0.19). There were no general complications resulting from the application of vancomycin.

Topical diluted vancomycin does not reduce periprosthetic infection risk, and has no effect on the occurrence of surgery wound complications. Considering the present findings, the use of vancomycin cannot be recommended in current practice to prevent infections following hip and knee arthroplasties. Finally, its use does not induce any specific complications, whether local (cicatrisation) or general (related to ototoxicity or nephrotoxicity).

III; case control study.

From several decades, the evolutions of the Incidence Rate (IR) of Primary Knee Arthroplasties are continuously increasing worldwide and have been widely studied in several countries. Some recent works have highlighted the fact that the IR is following a sigmoid curve composed of an exponential growth followed by a linear phase and finished by a plateau. Our objective is to assess the IR evolution of eleven European countries, representing thus a large proportion of this continent, regarding this sigmoid.

IRs of primary knee arthroplasties for Austria, Denmark, Finland, France, Germany, Hungary, Italy, Poland, Spain, Sweden, and the United Kingdom between 2005 and 2019 were retrieved from the EUROSTAT database. Several regression models were fitted to each country's IRs: Poisson, linear, asymptotic, logistic, and Gompertz regression. For each country and each model, the RMSE (Root Mean Square Error) and R2 were calculated and used to estimate their position with respect to this sigmoid curve.

The best regression models for knee arthroplasties varied following countries. Logistic and Gompertz regressions had the lowest RMSE and R2 values for Austria, Denmark, Germany, Sweden, and the UK. Hungary, Italy, and Poland favored the Poisson regression model. Finland and Spain presented difficulties in determining the optimal model (linear or Poisson), while France faced challenges in choosing between logistic, Gompertz, and linear regression.

In conclusion, the growth dynamics of IR differ across European countries. Some countries seem to have already reached a plateau and will therefore experience slight growth in the future.

Metal implants are commonly used in clinical practice. However, little is known regarding the prevalence of metal implants. Therefore, this study aimed to evaluate the prevalence of metal implants in the United States (US) among individuals aged ≥ 40 years. This study conducted a serial cross-sectional analysis of US adults aged ≥ 40 years who participated in the National Health and Nutrition Examination Survey (NHANES) (2015-2016 and 2017-March 2020). Self-reported questionnaires were used to assess whether the participants had metal implants inside their bodies. The primary outcome was the prevalence of metal implants among adults aged 40 years and older. Furthermore, weighted logistic regression analysis was employed to determine the changes in the prevalence of metal implants from 2015 to March 2020. Moreover, this study investigated the variation in metal implant prevalence by demographic factors based on the pooled NHANES cycles. All analyses were conducted based on 3,736 participants from the NHANES 2015-2016 and 6,387 participants from the NHANES 2017-March 2020. This study observed a high prevalence of metal implants among adults aged 40 and older (2015-2016: 27.23%; 2017-March 2020: 31.53%). Moreover, the results of the weighted logistic regression analysis showed that the prevalence of metal implants significantly increased from 2015 to March 2020, especially among older individuals, men, and White individuals. In addition, the results of the weighted logistic regression analysis indicated that the metal implant prevalence differed by age and race/ethnicity, in which older individuals and White individuals showed a significantly higher prevalence of metal implants than younger individuals and non-White individuals, respectively. There was a high prevalence of metal implants among US adults aged 40 and older, and the prevalence of metal implants significantly increased from 2015 to March 2020. Therefore, more attention needs to be paid to this special population, and it may be necessary to ensure accessibility and affordability and assess the potential long-term health impacts of metal implants, considering the increased prevalence of metal implants.

This study aimed to determine the effect of sexual education on sexual function and quality of activity after total hip arthroplasty (THA).

There were 31 patients who underwent THA who were randomly assigned to the education (n = 15) and the control (n = 16) groups in this randomized controlled trial. A sexual education session and an educational handout were provided to the study group after THA prior to discharge. Patients were evaluated 4 times throughout the study: preoperatively, at 1, 3, and 6 months after surgery. The data were collected by using the sociodemographic and medical data form, the Index of Female Sexual Function, the Sexual Quality of Life-Female (SQoL-F) Questionnaire, the visual analog scale (VAS) of the Fear of Sexual Activity, and the VAS of Satisfaction with Sexual Activity scales.

The mean sexual activity satisfaction score of the education group was higher in the second (95% confidence interval [Cl] [0.67 to 3.08]) and third follow-up (95% Cl [0.19 to 3.03]) (P < 0.05). Over time, the mean satisfaction scores of both groups increased (P < 0.05). The mean VAS fear of sexual activity scores at the first (95% CI [-2.81 to -0.48]), second (95% CI [-4.71 to -2.80]), and third (95% CI [-3.80 to -1.55]) follow-ups of the education group were significantly lower. Over time, the mean fear scores of both groups decreased (P < 0.05). The education group had higher mean SQoL-F scores at the first (95% CI [4.90 to 33.11], second (95% CI [7.62 to 34.31]), and third (95% CI [5.23 to 35.79]) follow-ups (P < 0.05). For the mean SQoL-F score, the difference between groups (F = 6.64), the change over time in both groups (F = 29.16), and the change over time between groups (F = 13.74) were statistically significant (P < 0.05). For the mean Index of Female Sexual Function score, it was found that the change over time was significantly different for both groups (F = 69.64, P < 0.05).

Sexual education after THA may improve satisfaction with sexual activity and quality of life.

With the expansion of the Affordable Care Act in 2014, there has been a growing interest in how the Medicaid population will affect postoperative outcomes following total knee arthroplasty (TKA). Studies have shown that lower socioeconomic status, non-Caucasian race, women, cardiac and renal disorders, and younger age have been associated with increased lengths of stay (LOS) after TKA. The primary purpose of our study was to compare the total complications and LOS among patients undergoing TKA who have cash, commercial, government, Medicaid, and Medicare insurances.

We queried a national, all-payer administrative claims database from 2016 to 2022 among patients undergoing TKA who had cash (n = 3,923), commercial (n = 966,169), government (n = 25,644), Medicaid (n = 56,184), and Medicare (n = 524,034) insurances. We compared and analyzed various baseline demographics, total complications, and LOS (<1 day, 1 to 2 days, 3 to 4 days, and >4 days), between the insurance types.

Medicaid and Medicaid insurance types had patients who had the most comorbidities at baseline, including a comorbidity index >3 (P < 0.0001), women, alcohol abuse, diabetes, obesity, tobacco use, chronic kidney disease, and congestive heart disease (all P < 0.0001). In accounting for comorbidities, Medicaid was the biggest risk factor for total complications (P < 0.001) as well as increased LOS after TKA at 4 to 6 days, 7 to 9 days, and >9 days (P < 0.0001).

Medicaid insurance is a risk factor for increased total complications and LOS following TKA. Appropriate preoperative and perioperative management of these patients is essential in order to mitigate the risk and burden on the health care system in this population.

Total joint arthroplasty (TJA) is one of the most common surgeries performed in the United States and is a durable and effective option in managing osteoarthritis of the hip and knee. Recent research regarding the procedure has focused on preoperative optimization and weight loss in particular. Obesity has been shown in prior studies to increase risks associated with TJA, and, as a result, debate has focused on whether a body mass index (BMI) cutoff is a prudent tool for preoperative optimization. This article discusses the ethical dilemma of instituting a BMI cutoff and reviews current literature regarding the topic.

Despite significant advancements in total knee arthroplasty (TKA), managing postoperative pain remains a substantial clinical challenge. With advances in surgical techniques and pharmacology, TKA perioperative analgesic strategies continue to evolve, necessitating ongoing reassessment of current data. Multimodal analgesia has become the standard for perioperative pain management in TKA; however, variations in its specific components and applications across studies create challenges in selecting the optimal analgesic approach. Evaluating these pain management strategies is essential for understanding their benefits, limitations, and appropriate use, allowing the development of individualized perioperative analgesic plans. This review aims to summarize current research on perioperative pain control in TKA and assess the effectiveness of different analgesic interventions.

Hip arthroscopy has one of the steepest learning curves of any orthopaedic surgery and has been reported to require upwards of more than 100 times the number of cases required to become efficient compared with other surgeries. Thus, hip arthroscopy deserves special attention regarding training, as it is technically challenging. Recent research shows that both immersive virtual reality (with a headset) and nonimmersive virtual reality (with a 2-year subscription, a high-definition touchscreen display, a benchtop hip manikin with pre-established arthroscopic portals, and magnetized arthroscopic instruments for tactile feedback) result in similar acquisition of procedural knowledge and technical skills, but immersive virtual reality is 132-fold less costly. Both types of virtual reality offer haptics, which replicate the "feel" of performing a hip arthroscopy, and both versions are far less costly than a cadaver lab, or the lost opportunity costs incurred with an additional year of fellowship training. Although virtual reality will never replace performing an actual surgery on an actual patient, it is shown to diminish the hip arthroscopy learning curve and is well worth the investment.

The purpose of this retrospective analysis of a prospective quality control project was to determine whether the use of intrawound vancomycin powder (IVP) decreases the rate prosthetic joint infection (PJI) within 90-days following primary total knee arthroplasty (TKA).

From October 2021-September 2022, a prospective quality control project was undertaken in which 10 high-volume arthroplasty surgeons alternated between using IVP and not using IVP each month. Patients who received IVP were compared to those who did not. The primary outcome was culture positive PJI within 90-days following primary total knee arthroplasty. Secondary outcomes included overall reoperation rate, wound complications, and readmission within 90-days post-operatively.

A total of 1,317 primary TKA patients were identified for analysis. Fifty-six and seven tenths percent (n = 747) of patients were included in the IVP group and 43.3% (n = 570) patients were included in the non-IVP group. The overall PJI rate was 0.5%. There was no difference in 90-day culture positive PJI rates between the groups (0.7% vs. 0.2%, p = 0.24). The overall reoperation rate did not differ between the IVP and non-IVP group (6.4% vs. 4.6%, p = 0.15). Reoperation for suspected infection was not statistically different by IVP administration (1.2% vs. 0.5%, p = 0.25). Additionally, there were no differences in the incidence of wound complications (p = 0.80) or readmissions (p = 0.15).

The overall infection rate for this cohort was low. IVP was not associated with decreased culture positive PJI, wound complications, reoperation or readmission rates. Further analysis of IVP use in TKA should be undertaken to fully determine its efficacy and safety profile.

The purpose of this study was to evaluate the effect of preoperative bisphosphonate use in patients who have osteoporosis on the risk of complications following primary total knee arthroplasty (TKA).

An administrative claims database was queried for patients who have osteoporosis undergoing primary TKA between 2010 and 2019 with a minimum of 2-year follow-up. Bisphosphonate-naive patients and bisphosphonate users, defined as patients who had a continuous prescription for bisphosphonates for a minimum of 6 months preoperatively, were matched 1:1 based on age, sex, and comorbidity burden. Patients undergoing nonelective TKA on chronic glucocorticoid therapy or receiving any other pharmacologic treatment for osteoporosis were excluded. The final cohort included 21,058 matched pairs of patients. The incidence of postoperative complications was identified via International Classification of Disease coding and compared between matched groups. A subgroup analysis was performed to examine outcomes among patients who underwent cemented and cementless TKA.

There was no difference in the incidence of periprosthetic fracture on univariate (0.7 versus 0.8%, P = 0.068) or multivariate testing (OR [odds ratio]: 1.24, 95% confidence interval [0.99 to 1.56]; P = 0.060). Bisphosphonate users were statistically less likely to undergo all-cause revision TKA at 2 years (OR: 0.84 [0.72 to 0.97]; P = 0.021). Patients who had osteoporosis were found to have an increased risk of periprosthetic fracture when TKA was performed with cementless implants (1.6 versus 0.4%; P = 0.033). However, when treated with bisphosphonates, patients who have osteoporosis demonstrated equivalent fracture rates regardless of implant type (1.3 versus 1.0%; P = 1.000).

While bisphosphonate use in patients who have osteoporosis did not decrease the risk of periprosthetic fracture, it did significantly lower the incidence of all-cause revision at 2 years, although the difference identified was small. Consideration should be given to performing cemented TKA in patients who have untreated osteoporosis, given the higher rate of periprosthetic fracture when cementless implants were utilized.

To explore the frequency of administration and the usage of the Hip Disability and Knee injury Osteoarthritis Outcome Scores (HOOS/KOOS) and their Physical function Short forms (HOOS-PS/KOOS-PS) by physiotherapists after total hip and knee arthroplasties (THA/TKA).

A cross-sectional study using an open online survey.

Primary care physiotherapy practices affiliated with the Dutch Association for Quality in Physiotherapy.

Physiotherapists with experience treating over five patients with a THA or TKA within the past 5 years.

One hundred and sixty-six physiotherapists completed the survey (median age: 40.0 years, female: 34%, median experience: 15.0 years). Of those, 32 did not administer the HOOS(-PS) or KOOS(-PS) ('non-users'), 41 administered only due to organisational requirements or guideline recommendations ('passive users') and 93 actively used them for individual patient treatment purposes ('active users'). 'Treatment evaluation', 'diagnosis', and 'prognosis' were most often reported as potential reasons to actively use the HOOS(-PS) or KOOS(-PS) for individual treatment purposes. Determinants associated with active use of the HOOS(-PS) or KOOS(-PS) appeared to be fewer years of experience as a physiotherapist, a larger treatment volume of THA/TKA, a younger age, and higher attitude scores regarding PROM use.

Most responding physiotherapists administer the HOOS(-PS) or KOOS(-PS), but their use for individual treatment is limited. Active users appear to be less experienced, younger, treat larger volumes of THA/TKA, and possess a more positive attitude towards using patient-reported outcome measures.

In response to various socio-economic factors and technological advancements, knee arthroplasty procedures have steadily increased. To date, epidemiological analyses have been conducted on a single-country basis. The aims of this article are: (1) to identify arthroplasty databases by country, (2) to verify the international comparability of coding, (3) to study retrospective epidemiological trends, and (4) to analyze projections by country. The hypothesis is that countries will follow similar trends, though with varying time lags.

A literature review from 2005 to 2023 was conducted following PRISMA recommendations on PubMed, Web of Science, and Cochrane, using the keywords: "Knee + Arthroplasty + Trends + Replacement + Epidemiology." Only articles featuring national analyses, based on references recognized by healthcare systems, were included.

Forty-eight articles, representing 16 countries, were selected. Europe was the most represented (47% of occurrences), followed by the USA (22%), Asia (20%), Oceania (8%), and Chile (2%). The data came from national databases or representative extrapolated samples. Extraction methods used precise national codes or specific definitions. Growth rates in volume and incidence were positive but varied between countries, with distinct dynamics and different phases of growth. Females had higher volumes and incidence rates (sex ratio 2/3), but growth was faster in males. Future forecasts, based on regression models (Poisson, linear, or logistic), predicted an increase in volumes of between +30% by 2030 and +805% by 2050.

The analysis of census systems revealed growth in knee arthroplasties in all countries, but with varying intensities depending on the period. These multifactorial disparities appeared to follow a similar pattern, staggered over time based on the countries' economic development.

IV; epidemiological review.

Preoperative prediction of the acetabular cup press-fit stability in total hip arthroplasty is necessary for clinical decision-making. This study aims to establish and validate machine learning models to investigate the feasibility of predicting the intraoperative press-fit stability of the acetabular cup in total hip arthroplasty (THA).

226 patients who underwent primary THA from 2018 to 2022 in our hospital were retrospectively enrolled. Patients were divided into press-fit stable or unstable groups according to the intraoperative pull-out test of the implanted cup. Then, they were randomly assigned to the training or test cohort in an 8:2 ratio. We used 3Dslicer software to segment the region of interest (ROI) of the patient's bilateral hip X-ray to extract radiomics features. The least absolute shrinkage and selection operator (LASSO) regression was used in our feature selection. Finally, four machine learning models were employed in this study, including support vector machine (SVM), random forest (RF), logistic regression (LR), and XGBoost (XGB). Decision curve analysis (DCA), and receiver operating characteristic (ROC) curves of the models were plotted. The area under the curve (AUC), diagnostic accuracy, sensitivity, and specificity were calculated as well. The AUCs of the four models were compared using the DeLong test.

Twenty-seven valuable radiomics features were determined by dimensionality reduction and selection. Regarding to the DeLong test, the AUC of the XGB model was significantly different from those of the other three models. (p < 0.05). Among all models, the XGB model exhibited the best performance with an AUC of 0.823 (95 % CI: 0.711-0.919) in the test cohort and showed optimal clinical efficacy according to the DCA.

Machine learning models based on X-ray radiomics can accurately predict the intraoperative press-fit stability of implanted cups preoperatively, providing surgeons with valuable information to lower the complication risk in THA.

There is an increase in degenerative arthropathies because of the increase in the longevity of world's population, making primary knee arthroplasties a procedure to recover quality of life without pain. There are factors associated with the length of hospital stay after this procedure.

To determine the risk factors influencing the hospital stay during the postoperative period of patients undergoing primary total knee arthroplasty with an enhanced recovery after surgery protocol (ERAS).

A retrospective study is carried out on patients undergoing primary total knee arthroplasty at an University Hospital in the period 2017-2020 using the ERAS protocol, during which 957 surgeries were performed.

Average age of 71.7±8.2years, 62.4% were women and the 77.3% were classified as ASAII. The significantly associated factors to an increased length of stay are: age (P=.001), ASA scale (P=.04), day of surgery (P<.001), blood transfusion (P<.001), postoperative hemoglobin level at 48-72h (P<.001), the time of first postoperative mobilization to ambulate and climb stairs (P<.001), the need for analgesic rescues (P=.003), and the presence of postoperative nausea and vomiting (P=.008).

There are statistically significant and clinically relevant factors associated with hospital stay. Determining these factors constitutes an advantage in hospital management, in the development of strategies to improve and optimize the quality of care and available health resources.

Cementless femoral fixation in total hip arthroplasty (THA) has increased in prevalence worldwide. However, cementless fixation in elderly patients is controversial due to the risks of periprosthetic fracture and aseptic loosening. This study evaluated outcomes in patients undergoing primary THA utilizing a cementless stem without a collar, comparing those less than 75 years to those older than 75 years.

Between 2011 and 2021, there were 2,605 cementless THAs performed by 4 surgeons utilizing a highly porous metal fixation surface without a collar and consistent clinical protocols. There were 469 patients who had an age ≥ 75 years. Revision rates, intraoperative fractures, and 90-day mortality were compared between cohorts. In the ≥ 75 year age group, there were more women, more American Society of Anesthesiologists physical status classification III or IV, a lower body mass index, and more kidney disease, osteoporosis, and thyroid disease (P ≤ .002).

All-cause revision rates trended lower for the ≥75 year age group compared to < 75 year (1.9 versus 3.5%, P = .082) at 20-months of follow-up. Moreover, there was no difference in all-cause femoral component revisions comparing ≥ 75 to < 75 year age groups (1.5 versus 2.2%, P = .375), with only 3 of 10 femoral revisions due to aseptic loosening being in the ≥ 75 year age group. Intraoperative fracture (0.2 versus 0.5%, P = .701) and 90-day mortality (0.2 versus 0.1%, P = .460) did not differ between ≥ 75 and < 75 year age groups.

Older patients had comparable revision rates compared to younger patients using cementless femoral fixation without a collar. Furthermore, there was no difference in 90-day mortality or intraoperative fracture rates. Study findings provide evidence for the safety and durability of cementless THA using collarless femoral stems in elderly patients ≥ 75 years of age.

III.

There is an increase in degenerative arthropathies because of the increase in the longevity of world's population, making primary knee arthroplasties a procedure to recover quality of life without pain. There are factors associated with the length of hospital stay after this procedure.

To determine the risk factors influencing the hospital stay during the postoperative period of patients undergoing primary total knee arthroplasty with an enhanced recovery after surgery protocol (ERAS).

A retrospective study is carried out on patients undergoing primary total knee arthroplasty at an University Hospital in the period 2017-2020 using the ERAS protocol, during which 957 surgeries were performed.

Average age of 71.7±8.2years, 62.4% were women and the 77.3% were classified as ASA II. The significantly associated factors to an increased length of stay are: age (p=.001), ASA scale (p=.04), day of surgery (p<.001), blood transfusion (p<.001), postoperative haemoglobin level at 48-72h (p<.001), the time of first postoperative mobilisation to ambulate and climb stairs (p<.001), the need for analgesic rescues (p=.003), and the presence of postoperative nausea and vomiting (p=.008).

There are statistically significant and clinically relevant factors associated with hospital stay. Determining these factors constitutes an advantage in hospital management, in the development of strategies to improve and optimise the quality of care and available health resources.

To determine, in a head-to-head comparison, which of two RAND-based knee replacement appropriateness criteria is optimal based on comparison to an externally validated method of judging good versus poor outcome.

Longitudinal data from the Osteoarthritis Initiative (OAI) and the Multicenter Osteoarthritis Study (MOST) were combined to produce a dataset of 922 persons with knee arthroplasty, 602 of which had adequate data for RAND classification and had their surgery within one year prior to a study visit. Data were used to determine appropriateness classification (i.e., Appropriate, Inconclusive, Rarely Appropriate) using modified versions of the first-generation and second-generation Escobar system. Growth curve analyses and multivariable regression were used to compare the two systems.

Neither system associated with the gold standard measure of good versus poor outcome. Distributions of appropriateness categories for the second-generation system were inconsistent with current evidence for knee arthroplasty outcome. For example, 16% of participants were classified as Appropriate and 64% as Rarely Appropriate for pain outcome. Distributions for the first-generation system aligned with current evidence.

The first-generation modified version of the Escobar appropriateness system is superior to the newer version but neither version associated with our gold standard growth curve analyses. Both systems only differentiate between patient classification groups preoperatively and up to ten months following surgery. Reliance on appropriateness criteria to inform long-term outcome is not warranted.

Although sonication is a valuable diagnostic tool for periprosthetic joint infections (PJI), it is not commonly utilized. We analyzed sonicate and intraoperative tissue culture results obtained from three hospitals to define the microbial etiology of PJIs in Korea. Furthermore, we investigated necessity of conducting regular fungal and mycobacterial cultures.

We retrospectively analyzed data for patients with suspected orthopedic-related infections between 2017 and 2022, who had undergone prostheses removal surgery. We included 193 patients with suspected PJIs, and bacterial (n = 193), fungal (n = 193), and mycobacterial (n = 186) cultures were conducted on both sonicate and intraoperative tissue samples. The diagnosis of PJI was based on the European Bone and Joint Infection Society (EBJIS) criteria.

Out of 193 patients, 121 (62.7%) had positive sonicate cultures, while 112 (58.0%) had positive periprosthetic tissue cultures. According to EBJIS criteria, a total of 181 patients were diagnosed with PJI, and 141 patients received microbiological confirmation through sonicate fluid culture or tissue culture. Of the 181 patients, 28 were classified with acute PJI (within 3 months of implantation) and 153 with chronic PJI. Among 141 patients, staphylococci were the most common organisms, accounting for 51.8% of cases, followed by Gram-negative organisms (15.6%), fungus (8.5%), and mycobacteria (3.5%). Nearly 91.7% of fungal isolates were Candida species, which also grew in bacterial cultures. In total, 11 cases cultured positive only in tissue culture, whereas 20 cases cultured positive only in sonicate culture. The antibiotic treatment plans were adjusted according to culture results.

Utilizing sonicate culture has greatly assisted in identifying pathogens responsible for chronic indolent PJIs, allowing suitable antimicrobial treatment. Based on few cases involving non-Candida and mycobacterial infections, it appears that routine fungal and mycobacterial cultures may not be necessary.

The health benefits of physical activity are well recognised. This study assessed whether golfers were more physically active after lower limb arthroplasty when compared to those that did not play golf (primary outcome). In addition pre and postoperative changes in health-associated quality of life (HAQoL) and joint specific outcomes between golfers and none golfers were assessed (secondary outcomes).

There were 304 patients [THA (n = 155) or TKA (n = 149)] prospectively registered during a 4-month period undergoing lower limb arthroplasty. The mean age was 70.0 (range 37-92, standard deviation 10.2) years and included 188 (61%) females and 120 (39%) males. They completed pre and postoperative questionnaires assessing recreational activity, physical activity, HAQoL (EuroQol [EQ]), joint specific health (Oxford scores), and satisfaction.

Golfers (n = 33, 10.9%) were more likely to achieve longer than 3 hours of moderate activity during a week (48.5% vs 38.0%, odds ratio (OR) 3.4, p = 0.045) and achieved their recommended activity level (96.8% vs 77.7%, OR 8.6, p = 0.015) compared to non-golfers following arthroplasty. Postoperative EQ5D (p = 0.034) and EQVAS (p = 0.019) were significantly greater in golfers. The joint specific Oxford hip score was greater in golfers compared to non-golfers (mean difference 5.6, p = 0.022), however no difference was observed in the Oxford knee score following TKA (p = 0.495).

Golfers were more likely to achieve their weekly recommended level of physical activity and had a greater HAQoL relative to those that did not play golf following lower limb arthroplasty. More specifically after THA golfers also had a greater postoperative joint specific outcome, but no such advantage was observed in those following TKA.

Level II, diagnostic study.

Periprosthetic femur fracture is a known complication after THA. The associated risk of cementless femoral component design for periprosthetic femur fracture in a registry population of patients older than 65 years has yet to be clearly identified.

(1) Is femoral stem geometry associated with the risk of periprosthetic femur fracture after cementless THA? (2) Is the presence or absence of a collar on cementless femoral implant designs associated with the risk of periprosthetic femur fracture after THA?

We analyzed American Joint Replacement Registry data from 2012 to March 2020. Unique to this registry is the high use of cementless femoral stems in patients 65 years and older. We identified 266,040 primary cementless THAs during the study period in patients with a diagnosis of osteoarthritis and surgeries linked to supplemental Centers for Medicare and Medicaid data where available. Patient demographics, procedure dates, and reoperation for periprosthetic femur fracture with revision or open reduction and internal fixation were recorded. The main analysis was performed comparing the Kheir and Chen classification: 42% (112,231 of 266,040) were single-wedge, 22% (57,758 of 266,040) were double-wedge, and 24% (62,983 of 266,040) were gradual taper/metadiaphyseal-filling cementless femoral components, which yielded a total of 232,972 primary cementless THAs. An additional analysis compared cementless stems with collars (20% [47,376 of 232,972]) with those with collarless designs (80% [185,596 of 232,972]). A Cox proportional hazard regression analysis with the competing risk of death was used to evaluate the association of design and fracture risk while adjusting for potential confounders.

After controlling for the potentially confounding variables of age, sex, geographic region, osteoporosis or osteopenia diagnosis, hospital volume, and the competing risk of death, we found that compared with gradual taper/metadiaphyseal-filling stems, single-wedge designs were associated with a greater risk of periprosthetic femur fracture (HR 2.9 [95% confidence interval (CI) 2.2 to 3.9]; p < 0. 001). Compared with gradual taper/metadiaphyseal-filling stems, double-wedge designs showed an increased risk of periprosthetic femur fracture (HR 3.0 [95% CI 2.2 to 4.0]; p < 0. 001). Collarless stems showed an increased risk of periprosthetic fracture compared with collared stems (HR 7.8 [95% CI 4.1 to 15]; p < 0. 001).

If cementless femoral fixation is used for THA in patients 65 years or older, surgeons should consider using gradual taper/metadiaphyseal-filling and collared stem designs because they are associated with a lower risk of periprosthetic femur fracture. Future investigations should compare gradual taper/metadiaphyseal-filling and collared cementless designs with cemented fixation in this population.

Level III, therapeutic study.

There is concern for cementless total knee arthroplasty (TKA) in patients with decreased bone mineral density (BMD) due to the potential increase in complications, namely failed in-growth or future aseptic loosening. Some data suggest that advances in cementless prostheses mitigate these risks; however this is not yet born out in long-term registry data. It is crucial to expand our understanding of the prevalence and etiology of osteoporosis in TKA patients, survivorship of cementless implants in decreased BMD, role of bone-modifying agents, indications and technical considerations for cementless TKA in patients with decreased BMD. The purpose of this study is to review current literature and expert opinion on such topics.

This study compares the re-revision rate and mortality following septic and aseptic revision hip arthroplasty (rTHA) in registry data, and compares the outcomes to previously reported data.

This is an observational cohort study using data from the German Arthroplasty Registry (EPRD). A total of 17,842 rTHAs were included, and the rates and cumulative incidence of hip re-revision and mortality following septic and aseptic rTHA were analyzed with seven-year follow-up. The Kaplan-Meier estimates were used to determine the re-revision rate and cumulative probability of mortality following rTHA.

The re-revision rate within one year after septic rTHA was 30%, and after seven years was 34%. The cumulative mortality within the first year after septic rTHA was 14%, and within seven years was 40%. After multiple previous hip revisions, the re-revision rate rose to over 40% in septic rTHA. The first six months were identified as the most critical period for the re-revision for septic rTHA.

The risk re-revision and reinfection after septic rTHA was almost four times higher, as recorded in the ERPD, when compared to previous meta-analysis. We conclude that it is currently not possible to assume the data from single studies and meta-analysis reflects the outcomes in the 'real world'. Data presented in meta-analyses and from specialist single-centre studies do not reflect the generality of outcomes as recorded in the ERPD. The highest re-revision rates and mortality are seen in the first six months postoperatively. The optimization of perioperative care through the development of a network of high-volume specialist hospitals is likely to lead to improved outcomes for patients undergoing rTHA, especially if associated with infection.

There are conflicting reports in the literature regarding the risk of revision after primary total knee replacement (TKR) in obese patients. The purpose of this study was to investigate if body mass index (BMI) influences the risk of revision 3-9 years after primary TKR.

All patients undergoing a primary TKR in our institution from 2014 to 2018 were included in a retrospective study. The effect of BMI on all-cause revision was estimated in a logistic regression analysis. A directed acyclic graph was created to identify variables affecting the primary endpoint (revision). According to the directed acyclic graph, adjustment was only needed for age and smoking. However, we also included variables thought to influence the revision risk based on clinical experience and previous research. The final logistic regression analysis was therefore adjusted for age, sex, smoking status, diabetes mellitus and the American Society of Anesthesiologists classification.

One thousand fifty-nine primary TKR patients with a mean age of 68.1 (standard deviation 9.4) years were included. There were 609 (57.5%) women, and the median follow-up time was 5.6 (range 3.0-9.0) years. There were 41 (3.9%) revisions. BMI did not affect the risk of revision when adjusted for relevant covariates in a multivariate logistic regression analysis (odds ratio 0.99, 95% confidence interval 0.93-1.05, P = .6).

BMI did not influence the risk of revision rate 3-9 years after TKR.

Several studies have compared the pros and cons of simultaneous bilateral versus staged bilateral hip and knee replacement but the outcomes of these two surgical options remains a matter of controversy. This study aimed to evaluate demographic features, incidence and hospitalization rates of bilateral one stage total hip and knee arthroplasty in Italy.

The Italian Ministry of Health's National Hospital Discharge Reports (SDO) were used to gather data. This study referred to the adult population (+ 20 years of age) from 2001 to 2015 for hip arthroplasty and from 2001 to 2016 for knee arthroplasty.

Overall, 1,544 bilateral simultaneous hip replacement were carried out. The incidence rate was 0.21 cases per 100,000 adult Italian residents. Male/female ratio was 1.1. The average days of hospital stay was 11.7 ± 11.8 days. The main primary codified diagnosis was: osteoarthrosis, localized, primary, pelvic region and thigh (ICD code: 715.15). 2,851 bilateral simultaneous knee replacement were carried out. The incidence rate was 0.37 cases per 100,000 adult Italian residents. Male/female ratio was 0.6. The average days of hospital stay was 7.7 ± 5.8 days. The main primary codified diagnosis was: osteoarthrosis, localized, primary, lower leg (ICD code: 715.16).

The burden of hip and knee osteoarthrosis as a leading cause of bilateral joint replacement is significant in Italy. The national registers' longitudinal analysis may provide data for establishing international guidelines regarding the appropriate indications for one stage bilateral simultaneous hip or knee replacement versus two stage.

Hip replacement surgery is a common procedure that relies on the implant's design to withstand daily activities. This study aims to investigate the impact of different surface groove designs on the performance of solid hip implants using finite element analysis (FEA) and optimization techniques. The study evaluates the influence of grooves on the stress distribution and total deformation of the implant, considering three designs: no grooves, horizontal grooves, and vertical grooves on the surface of the femoral head. The simulations were conducted using Ansys Mechanical, and the optimization process was carried out using the general full factorial design method in Minitab software. The results demonstrate that the groove design significantly affects the stress distribution and wear of the implant. The vertical groove design shows better overall results, indicating the best performance. The study also evaluated the influence of force on the performance of the implant, with different load range. The optimization process using the general full factorial design method revealed that the optimal groove design was a vertical model with an optimized groove depth and width. These findings offer valuable insights into the impact of surface groove designs on the performance of solid hip implants, leading to better patient outcomes and longer implant lifespan. Overall, this study provides a comprehensive understanding of the effect of surface groove design on the performance of solid hip implants.

Background: Post-operative urinary retention (POUR) is a common complication following total hip arthroplasty (THA) and total knee arthroplasty (TKA). Spinal anaesthetic has been associated with an increased risk of POUR, whilst other risk factors remain unclear. This study aims to identify modifiable and non-modifiable risk factors of POUR for THA and TKA patients. Methods: A single-centre retrospective cohort study of patients admitted to our hospital over the course of 6 weeks from September to October 2021 for a THA or TKA. All patients who underwent elective THA/TKA were included, and trauma cases were excluded. Results: Ninety-two consecutive patients were included in this study. The overall rate of POUR was 17%. A shorter operative duration resulted in a reduced risk of POUR (median duration of non-retention patients, 88 min vs. 100 min POUR patients; odds ratio, 0.97; 95% CI, 0.95-0.99, p = 0.018). The median bladder volume of patients with urinary retention at the point of diagnosis was 614 mL (range, 298-999 mL). The arthroplasty type, anaesthetic technique, pre-operative morphine use, body mass index, age, cardiovascular disease, and renal disease were found to have no significant association with POUR. Conclusions: A reduced operative time of arthroplasty surgery is associated with a decreased risk of POUR. Patients with a prolonged operative time should have an increased frequency of micturition monitoring in the immediate post-operative period.

Instability is a common indication for revision total hip arthroplasty (THA). However, even after the initial revision, some patients continue to have recurrent dislocation. The aim of this study was to assess the risk for recurrent dislocation after revision THA for instability.

Between 2009 and 2019, 163 patients underwent revision THA for instability at Stanford University Medical Center. Of these, 33 (20.2%) required re-revision due to recurrent dislocation. Cox proportional hazard models, with death and re-revision surgery for periprosthetic infection as competing events, were used to analyze the risk factors, including the size and alignment of the components. Paired t-tests or Wilcoxon signed-rank tests were used to assess the outcome using the Veterans RAND 12 (VR-12) physical and VR-12 mental scores, the Harris Hip Score (HHS) pain and function, and the Hip disability and Osteoarthritis Outcome score for Joint Replacement (HOOS, JR).

The median follow-up was 3.1 years (interquartile range 2.0 to 5.1). The one-year cumulative incidence of recurrent dislocation after revision was 8.7%, which increased to 18.8% at five years and 31.9% at ten years postoperatively. In multivariable analysis, a high American Society of Anesthesiologists (ASA) grade (hazard ratio (HR) 2.72 (95% confidence interval (CI) 1.13 to 6.60)), BMI between 25 and 30 kg/m2 (HR 4.31 (95% CI 1.52 to 12.27)), the use of specialized liners (HR 5.39 (95% CI 1.97 to 14.79) to 10.55 (95% CI 2.27 to 49.15)), lumbopelvic stiffness (HR 6.03 (95% CI 1.80 to 20.23)), and postoperative abductor weakness (HR 7.48 (95% CI 2.34 to 23.91)) were significant risk factors for recurrent dislocation. Increasing the size of the acetabular component by > 1 mm significantly decreased the risk of dislocation (HR 0.89 (95% CI 0.82 to 0.96)). The VR-12 physical and HHS (pain and function) scores improved significantly at mid term.

Patients requiring revision THA for instability are at risk of recurrent dislocation. Higher ASA grades, being overweight, a previous lumbopelvic fusion, the use of specialized liners, and postoperative abductor weakness are significant risk factors.

The number of artificial total hip revision arthroplasties is increasing yearly in China, and >50% of these cases have acetabular defects. Accurately locating and quantifying the bone defect is one of the current challenges of this surgery. Thus, the objective of the present study was to simulate acetabular implantation with the aid of Mimics 17.0 software (Materialise NV) in patients with loosened acetabular prosthesis, to evaluate the 'ideal acetabular center' and the 'actual acetabular center' to guide the choice of prosthesis and surgical method. From January 2017 to June 2021, the present study included 10 hips from 10 patients [seven men (seven hips) and three women (three hips)]. In all patients, the Mimics software was applied to simulate the dislocation of the femoral prosthesis and acetabular prosthesis implantation before surgery; calculate the height difference between the 'ideal acetabular center' and the 'actual acetabular center' to assess the bone defect; confirm the size of the acetabular prosthesis, abduction angle, anteversion angle and bone coverage of the acetabular cup; and measure the intraoperative bleeding and postoperative follow-up Harris score of the hip joint. After statistical analysis, the present study revealed that digital simulation assistance could improve the accuracy of hip revision acetabular prosthesis implantation, reduce postoperative shortening of the affected limb, especially for surgeons with relatively little experience in hip revision surgery, and greatly reduce the occurrence of complications such as hip dislocation because of poor postoperative prosthesis position.

The coronavirus 2019 (COVID-19) pandemic led to a marked decrease in elective surgical volume and orthopaedic device sales. The aim of this paper was to quantify this decrease and the related financial impact on the largest hip/knee arthroplasty companies by: (1) tracking individual hip/knee company valuations; (2) calculating aggregate changes in overall hip/knee arthroplasty market valuations; and (3) quantifying quarterly hip/knee revenues relative to prior years.

Financial data on the top five hip/knee arthroplasty companies by size between January 1, 2019, and October 1, 2020, was collected from a Wall Street financial database, S&P Capital IQ. Changes in valuation of these companies were compared against benchmark market indices, the S&P500 and Vanguard Healthcare ETF. U.S. hip/knee arthroplasty-specific revenue for Q1 and Q2 of 2019 and 2020 was collected from Securities Exchange Commission 10-Q forms. Quarterly revenue changes were calculated using 1-2Q19 revenues as baselines and aggregate to approximate the overall hip/knee arthroplasty market.

The top five hip/knee companies lost $179.2 billion (32.7% loss) in market value from pre COVID-19 market highs to COVID-19 market lows (March 2020), while S&P500 and Vanguard Healthcare ETF decreased 36.1 and 33.2%, respectively. From market lows to October 2020, arthroplasty companies rallied 38.6% while the S&P500 and Vanguard Healthcare ETF regained 43.5 and 56.4% respectively. Notably, this occurred while aggregate 1Q/2Q20 revenue lagged 7.1/41.8% relative to 2019, with an overall decrease of $1.58B (24.8%).

Similar to the overall market and healthcare sector, the top five hip/knee arthroplasty companies have recovered from their COVID market lows. Our results reveal that the valuations of hip/knee companies remained robust during COVID, even as revenues fell, likely due to strong investor confidence in the industry outlook and the greater overall healthcare system utilization.

In two-stage exchange for periprosthetic joint infection (PJI), adding antibiotics to cement spacers is the standard of care; however, little is known about optimal dosage. There is emphasis on using >3.6 g of total antibiotic, including ≥2.0 g of vancomycin, per 40 g of cement, but these recommendations lack clinical evidence. We examined whether recommended antibiotic spacer doses affect treatment success.

This was a retrospective review of 202 patients who underwent two-stage exchange for PJI from 2004 to 2020 with at least 1-year follow-up. Patients were separated into high (>3.6 g of total antibiotic per 40 g of cement) and low-dose spacer groups. Primary outcomes were overall and infectious failure.

High-dose spacers were used in 80% (162/202) of patients. High-dose spacers had a reduced risk of overall (OR, 0.37; P = 0.024) and infectious (OR, 0.35; P = 0.020) failure for infected primary arthroplasties, but not revisions. In multivariate analysis, vancomycin dose ≥2.0 g decreased the risk of infectious failure (OR, 0.31; P = 0.016), although not overall failure (OR, 0.51; P = 0.147).

During two-stage exchange for PJI, spacers with greater than 3.6 g of total antibiotic may reduce overall and infectious failure for infected primary arthroplasties. Furthermore, using at least 2.0 g of vancomycin could independently decrease the risk of infectious failure.

To compare short-term complications and readmission rates, in patients treated with simultaneous versus staged bilateral total hip arthroplasty (THA) within a year from the index procedure.

We reviewed the charts of patients that underwent simultaneous and staged-within a year-bilateral THA, between 2016 and 2020. Preoperative baseline characteristics were evaluated, while differences in terms of 30-day major and 30-day minor complications and readmission rates were compared between the groups.

One-hundred-sixty patients (mean age, 64.3 years; SD, ± 11.7) were identified. Seventy-nine patients were treated with simultaneous (Group A) and eighty-one patients with staged (Group B) THA. There were no differences in baseline characteristic between the two groups (p  > 0.050). Group A was more likely to receive general anesthesia (43% vs. 9.9%, p < 0.001) and had longer total operative time (182.8 vs. 128.0 min, p  < 0.001). Group A had an overall shorter total length of hospital stay (5.8 vs. 8.6 days, p  < 0.001). No differences in transfusion rates (p  = 0.229) and no differences in major and minor complications (p > 0.05) were identified. Postoperative visits at the emergency department or readmissions were similar between the two groups (p > 0.050).

This study shows that similar complication and readmission rates are expected after simultaneous and staged THA. Simultaneous bilateral THA is a safe and effective procedure, that should be considered for patients that present with radiologic and clinical bilateral hip disease.

It is unknown if the National Inpatient Sample (NIS) remains suitable to conduct projections for total knee arthroplasty (TKA) and total hip arthroplasty (THA), after their removal from "inpatient-only lists" in 2018 and 2020, respectively. We aimed to: (1) quantify primary THA and TKA volume from 2008 to 2018; (2) project estimates of future volume of THA and TKA until 2050; and (3) compare projections based on NIS data from 2008 to 2018 and 2008 to 2017, respectively. We identified all primary THA and TKA performed from 2008 to 2018 from the NIS. The projected volumes of THA and TKA were modeled using negative binomial regression models while incorporating log-transformed population data from the Centers for Disease Control and Prevention. Annual volume increased by 26% for THA and 11% for TKA (2008/2018: THA: 360,891/465,559; TKA:592,352/657,294). Based on 2008 to 2018 data, THA volume is projected to grow 120%, to 1,119,942 THAs by 2050. While, based on 2008 to 2017 data, THA volume is projected to grow 136%, to 1,219,852 THAs by 2050. Based on 2008 to 2018 data, TKA volume is projected to grow 4%, to 794,852 TKAs by 2050. While, based on 2008 to 2017 data, TKA volume is projected to grow 28%, to 1,037,474 TKAs by 2050. Projections based on 2008 to 2017 data estimated up to 240,000 (23%) more annual TKAs by 2050, compared with projections based on 2008 to 2018 data. The largest discrepancy among THA projections was an 8.2% difference (99,000 THAs) for 2050. After 2018 for TKA, and potentially 2020 for THA, projections based on the NIS will have to be interpreted with caution and may only be appropriate to estimate future inpatient volume. Level of evidence is prognostic level II.

No objective radiographic scoring system exists to classify metaphyseal cone stability. Our purpose was to create a novel, systematic method to radiographically evaluate metaphyseal cone fixation based on radiographic findings suggestive of cone stability.

A retrospective analysis was conducted of revision total knee arthroplasty patients (6/2015-12/2017) using porous titanium femoral or tibial metaphyseal cones in conjunction with short cemented stems (50 mm-75 mm). Minimum follow-up was 2 years. Survivorship free of aseptic loosening and reoperation, as well as radiographic evaluation using a novel cone zone scoring system were analyzed.

Forty-nine revision total knee arthroplasties were included in the study (12 femoral, 48 tibial cones), the majority, performed for aseptic loosening (25/49, 51%). Median follow-up was 39 months (range 25-58). Using the radiographic cone zone scoring method, >90% of all femoral cones were classified as likely stable or stable with strong, statistically significant intraclass correlations between all 3 reviewers. Similarly, >97% of all tibial cones were classified as likely stable or stable, with moderate, statistically significant intraclass correlations between all 3 reviewers. Only 1 femoral and 1 tibial cone were considered at risk of loosening. The study sample demonstrated 100% survivorship free of revision for aseptic loosening without evidence of radiographic loosening in any case.

Using a novel systematic cone zone scoring and classification method, the overwhelming majority of femoral and tibial cones were classified as likely stable or stable, with no identified cases of aseptic loosening or related revision. Further studies are needed to validate this objective classification method.

Total hip and knee replacements are the most common orthopedic procedures performed due to osteoarthritis. Pain is an intrinsic symptom accompanying osteoarthritis, persisting long before surgery, and continuing during the preoperative and postoperative periods. Appropriate pain management after surgery determines the comfort, duration, and cost of hospitalization, as well as the effectiveness of postoperative rehabilitation. Individual differences in pain perception and tolerance in orthopedic patients remain an important research topic. Therefore, the aim of this study was to investigate the predictors of analgesic requirements (morphine, acetaminophen, and ketoprofen), including individual pain threshold and tolerance, body mass index (BMI), diabetes, and beliefs about pain control in patients undergoing elective hip or knee arthroplasty using a multilevel regression model (N = 147, 85 women, 62 men, 107 after hip replacement, and 40 after knee replacement). Results: Higher pain tolerance was associated with a lower dose of morphine per kg after surgery. Patients undergoing hip surgery received a lower dose of ketoprofen than patients undergoing knee surgery. The more the patient believed in personal pain control, the stronger the negative relationship between pain tolerance and morphine requirement. The lowest doses were given to patients with the highest pain tolerance and the greatest belief in personal control. Factors such as belief in pain control and pain tolerance should be considered in comprehensive postoperative pain management in orthopedic patients to reduce opioid doses and, thus, side effects.

Knee osteoarthritis (KOA) is a prevalent chronic joint disease caused by various factors. Mesenchymal stem cells (MSCs) therapy is an increasingly promising therapeutic option for osteoarthritis. However, the chronic inflammation of knee joint can severely impede the therapeutic effects of transplanted cells. Gelatin microspheres (GMs) are degradable biomaterial that have various porosities for cell adhesion and cell-cell interaction. Excellent elasticity and deformability of GMs make it an excellent injectable vehicle for cell delivery.

We created Wharton's jelly derived mesenchymal stem cells (WJMSCs)-GMs complexes and assessed the effects of GMs on cell activity, proliferation and chondrogenesis. Then, WJMSCs loaded in GMs were transplanted in the joint of osteoarthritis mice. After four weeks, joint tissue was collected for histological analysis. Overexpressing-luciferase WJMSCs were performed to explore cell retention in mice.

In vitro experiments demonstrated that WJMSCs loaded with GMs maintained cell viability and proliferative potential. Moreover, GMs enhanced the chondrogenesis differentiation of WJMSCs while alleviated cell hypertrophy. In KOA mice model, transplantation of WJMSCs-GMs complexes promoted cartilage regeneration and cartilage matrix formation, contributing to the treatment of KOA. Compared with other groups, in WJMSCs+GMs group, there were fewer cartilage defects and with a more integrated tibia structure. Tracking results of stable-overexpressing luciferase WJMSCs demonstrated that GMs significantly extended the retention time of WJMSCs in knee joint cavity.

Our results indicated that GMs facilitate WJMSCs mediated knee osteoarthritis healing in mice by promoting cartilage regeneration and prolonging cell retention. It might potentially provide an optimal strategy for the biomaterial-stem cell based therapy for knee osteoarthritis.

As recent studies demonstrate an ongoing debate surrounding outcomes and complications with respect to different total hip arthroplasty (THA) approaches, patient-reported outcome measures (PROMs) may provide valuable information for clinician and patient decision-making. Therefore, our systematic review aimed to assess how surgical approach influences patient-reported outcomes.

5 online databases were queried for all studies published between January 1, 1997 and March 4, 2022 that reported on PROMs across various surgical approaches to THA. Studies reporting on PROMs in primary THA patients segregated by surgical approach were included. Articles reporting on revision THA, hip resurfacing, and arthroscopy were excluded. Mantel-Haenszel (M-H) models were utilised to calculate the pooled mean difference (MDs) and 95% confidence interval (CIs).

No differences between the DAA and other approaches were observed when evaluating HOOS (MD -0.28; 95% CI, -1.98-1.41; p = 0.74), HHS (MD 2.38; 95% CI, -0.27-5.03; p = 0.08), OHS (MD 1.35; 95% CI, -2.00-4.71; p = 0.43), FJS-12 (MD 5.88; 95% CI, -0.36-12.12; p = 0.06), VAS-pain (MD -0.32; 95% CI, -0.68-0.04; p = 0.08), and WOMAC-pain (MD -0.73; 95% CI, -3.85-2.39; p = 0.65) scores. WOMAC (MD 2.47; 95% CI, 0.54-4.40; p = 0.01) and EQ-5D Index (MD 0.03; 95% CI, 0.01-0.06; p = 0.002) scores were found to significantly favour the DAA cohort over the other approaches. Only the EQ-5D index score remained significant following sensitivity analysis.

Superiority of any 1 approach could not be concluded based on the mixed findings of the present analysis. Although our pooled analysis found no significant differences in outcomes except for those measured by the EQ-5D index, a few additional metrics, notably the WOMAC, HHS, FJS-12, and VAS-pain scores, leaned in favour of the DAA.