Hip arthroplasty

Association of self-efficacy, risk attitudes, and time preferences with health-related quality of life and functioning after total hip or knee replacement - Results of the MobilE-TRA 2 cohort

BACKGROUND

While total hip and knee replacement (THR/TKR) surgery are effective measures to restore functioning and reduce pain in patients with severe osteoarthritis (OA), long-term treatment effects vary among patients. Following behavioral economic theory, these differences may be partially attributed to the impact of personality traits on individual strategies to approach post-surgical challenges. This study explored the associations between self-efficacy, willingness to take risk regarding health (H-WTTR), and future orientation, and the 3-month course of health-related quality of life (HRQoL) and OA-specific health status.

METHODS

As part of the prospective and observational MobilE-TRA 2 cohort study, 147 patients aged 60 years and older were assessed by self-administered questionnaires before and three months after THR/TKR at a single German hospital. As indicators for the surgical outcome, HRQoL was assessed by the EuroQol Five-Dimensional Five-Level Questionnaire (EQ-5D-5L), including the visual analogue scale (EQ-VAS), and functioning was assessed by the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) using the global score, function score, and pain score. All WOMAC scores were transformed into scales with 0 = worst health and 100 = best health. Self-efficacy was measured using the General Self-Efficacy Short Scale. H-WTTR and future orientation were assessed by single-item questions on 11-point Likert scales. The associations between these personality traits and the 3-month change in the outcome scores were analyzed using linear regression models for THR and TKR respectively.

RESULTS

In THR patients a one-point-increase in self-efficacy was associated with improvements in EQ-5D-5L (β=0.0704; p=0.0099), WOMAC global (β=6.6337; p=0.0139), WOMAC function (β=8.2557; p=0.0046), and WOMAC pain (β=5.9994; p=0.0232). For TKR, only the association of self-efficacy with the EQ-VAS change-score was significant (β=5.8252; p=0.0482). Self-efficacy demonstrated weak positive, but not significant associations with all WOMAC scores and a negative association close to zero with the EQ-Index. H-WTTR and future orientation showed no significant associations to changes of the outcome scores.

CONCLUSIONS

Self-efficacy appears to be a prognostic factor for better THR/TKR outcomes after three months. If these findings can be confirmed in further research, strategies to improve self-efficacy should be considered in prehabilitation programs.

TRIAL REGISTRATION

Not applicable.

The Type of Preoperative Oral Antithrombotics as a Risk Factor for Venous Thromboembolism After Hip Surgery: A Retrospective Study

Background and Objectives: Hip surgery is increasingly performed among elderly patients. Oral antithrombotics, which are taken for patients' underlying diseases, are a main concern regarding perioperative bleeding. Postoperative venous thromboembolism (VTE) is a leading cause of mortality after hip surgery. Therefore, administration of preoperative oral antithrombotics is a double-edged sword in hip surgery. In this study, we examined the correlation between the occurrence of postoperative VTE and the type of oral antithrombotics administered preoperatively. Materials and Methods: We analyzed the medical records of 601 patients aged 19 and over who underwent hip surgery from January 2021 to June 2023. The patients were assigned to two groups as follows: Groups VTE+ (patients who developed postoperative VTE) and VTE- (patients who did not develop postoperative VTE), respectively. Results: Of the 139 patients who had been taking oral antithrombotics for 6 months or more, 24 were allocated to group VTE+ and 115 to group VTE-, respectively. The number of patients who took clopidogrel and cilostazol was significantly higher in groups VTE- and VTE+, respectively (12.5 vs. 33.9%, p = 0.038, odds ratio (OR) = 0.278, 95% confidence interval (CI) = 0.078-0.991; 20.8 vs. 5.2%, p = 0.010, 95% CI = 1.325-17.245; group VTE+ vs. group VTE-). Preoperative albumin levels were significantly lower in group VTE+ (3.4 ± 0.6 g/dL vs. 3.7 ± 0.4 g/dL, p = 0.004, OR = 0.285, 95% CI = 0.115-0.702). In multivariate regression analysis, the results were statistically significant for clopidogrel, cilostazol, and preoperative albumin levels (p = 0.035, OR = 0.237, 95% CI = 0.062-0.901; p = 0.011, OR = 6.479, 95% CI = 1.542-27.226; p = 0.002, OR = 0.211, 95% CI = 0.080-0.558). Conclusions: Among the patients who had been taking oral antithrombotics for ≥6 months, clopidogrel had a prophylactic effect, but cilostazol showed an aggravating effect on postoperative VTE in hip surgery. Preoperative hypoalbuminemia increases the risk of postoperative VTE in hip surgery.

The use of an ultrasonic cement removal device in revision hip and knee arthroplasty-A matched case-control study

Purpose

The objective of this case series was to investigate the effect of ultrasound-guided cement removal devices on operating time and patient safety in the revision of cemented knee and hip arthroplasties.

Methods

A total of 11 cases were examined in which ultrasound-guided cement extraction was utilised for implant removal. The primary endpoint of the study was the duration of the surgery. Additionally, the cohort was analysed for the occurrence of intraoperative fractures or postoperative ossification. Postoperative laboratory dynamics of haemoglobin and C-reactive protein levels were also investigated. A matched group of 11 patients who underwent revision arthroplasty using conventional techniques to remove bone cement served as the reference group.

Results

Ultrasound-guided removal of cement from the medullary canal was associated with a significantly longer operation time (187.19 min ± 54.4 vs. 121.91 min ± 43.5, (p = 0.0026). Furthermore, there was a significant decrease in haemoglobin drop relative to baseline haemoglobin levels when ultrasound-guided tools were employed for cement removal (2.36 g/dL ± 1.9 vs. 4.54 g/dL ± 1.9, p = 0.0015). Moreover, an intraoperative fracture complication of the femoral shaft was observed when the cement was removed using an ultrasonic cement stripper.

Conclusion

A comparison between the two groups reveals a significant increase in surgical duration when cement removal was performed using ultrasound-guided technique. Simultaneously, the use of an ultrasound-assisted system for cement removal did not mitigate the risk of intraoperative bone perforation. Based on the data presented in this study, the authors cannot conclude that the use of ultrasound-guided devices for the removal of cement residues from the medullary canal during revision surgery is superior to conventional techniques.

Level of Evidence

Level IV.

Hospital Safety-Net Burden is Associated with Perioperative Outcomes in Primary Total Hip Arthroplasty: A Multistate Retrospective Analysis, 2015-2020

Total hip arthroplasty (THA) is a widely performed surgical procedure in the United States, but disparities in THA outcomes related to hospital-level factors, such as safety-net burden, are underexplored. This study expands on previous research by analyzing multicenter, multistate data from 2015 to 2020 to investigate the impact of hospital safety-net burden-defined as the proportion of services billed to Medicaid and uninsured patients-on THA outcomes. This study is a retrospective analysis using data from the State Inpatient Databases for Florida, Kentucky, Maryland, New York, Washington, New Jersey, and North Carolina. The study cohort included 543,814 inpatient primary THA admissions, with patient demographics, comorbidities, and hospital characteristics analyzed across 3 categories of hospital safety-net burden (low, medium, and high). Generalized linear mixed models assessed the association between safety-net burden and in-hospital mortality and postoperative complications, whereas multilevel negative binomial regression evaluated the impact on hospital length of stay. The study findings indicate that patients undergoing THA at hospitals with high safety-net burden had significantly higher odds of in-hospital mortality (adjusted odds ratio [aOR]: 1.20, 95% confidence interval [CI]: 1.02-1.42), postoperative complications (aOR 1.33, 95% CI 1.20-1.48), and longer hospital stays (adjusted incidence rate ratio 1.15, 95% CI 1.10-1.21) compared with those at low-burden hospitals. These results suggest that hospitals with higher safety-net burden, often serving more vulnerable populations, may have suboptimal perioperative processes and protocols, leading to poorer outcomes. The study underscores the need for targeted interventions to improve THA outcomes in these hospitals.

Optogenetic activation of mechanical nociceptions to enhance implant osseointegration

Orthopedic implants with high elastic modulus often suffer from poor osseointegration due to stress shielding, a phenomenon that suppresses the expression of intracellular mechanotransduction molecules (IMM) such as focal adhesion kinase (FAK). We find that reduced FAK expression under stress shielding is also mediated by decreased calcitonin gene-related peptide (CGRP) released from Piezo2+ mechanosensitive nerves surrounding the implant. To activate these nerves minimally invasively, we develop a fully implantable, wirelessly rechargeable optogenetic device. In mice engineered to express light-sensitive channels in Piezo2+ neurons, targeted stimulation of the L2-3 dorsal root ganglia (DRG) enhances localized CGRP release near the implant. This CGRP elevation activates the Protein Kinase A (PKA)/FAK signaling pathway in bone marrow mesenchymal stem cells (BMSCs), thereby enhancing osteogenesis and improving osseointegration. Here we show that bioelectronic modulation of mechanosensitive nerves offers a strategy to address implant failure, bridging neuroregulation and bone bioengineering.

Comparing general and regional anesthesia in patients undergoing primary total hip arthroplasty: analysis of national health insurance data in Korea

Objectives

To compare the effects of general and regional anesthesia on clinical outcomes following primary total hip arthroplasty (THA).

Methods

This retrospective study using data from the Korean National Health Insurance Research Database included 1,522 patients who underwent THA under general anesthesia (n = 640) or regional anesthesia (n = 882) between 2002 and 2015. We compared the mortality and complication rates within 30 days after surgery.

Results

Prosthesis failure (1.56% vs. 0.45%, p = 0.025), admission to the intensive care unit (9.53 vs. 5.44%, p = 0.0023), and total cost (₩7,332,515 vs. ₩6,833,295, p < 0.0001) were higher in the general anesthesia group than in the regional anesthesia group. No significant differences were observed in mortality (0.94% vs. 0.57%, p = 0.54), transfusion rate (81.1% vs. 80.9%, p = 0.94), length of hospital stay (45 vs. 45 days, p = 0.23), or other complications between the groups. Similar results were observed in propensity-score matched analysis (n = 640 patients per group).

Conclusion

Our study showed that both anesthesia types resulted in comparable mortality and complication rates in patients who underwent THA, but the costs differed.

Predictive Factors for Gait Recovery in Patients Undergoing Total Hip Arthroplasty: A Propensity Score Weighting Analysis

Objectives: This paper's objective was to identify clinical predictors, especially modifiable ones, associated with postoperative gait recovery in total hip arthroplasty (THA) patients, utilizing propensity score weighting (PSW) to control confounding factors. Methods: This retrospective cohort study included 221 patients who underwent primary unilateral THA. We used PSW analysis to balance patient characteristics. Univariate and multivariate logistic regression analyses were applied to determine predictors of improved gait recovery, assessing variables such as age, gender, and postoperative muscle strength. Results: Independent predictors of favorable gait recovery were male gender (Odds Ratio [OR]: 1.382; 95% Confidence Interval [CI]: 1.225-1.560; p < 0.001), younger age (OR: 0.990 per year; 95% CI: 0.985-0.995; p < 0.001), and postoperative hip flexor muscle strength greater than grade 3 (OR: 1.516; 95% CI: 1.177-1.953; p = 0.002). Muscle strength emerged as a modifiable factor, suggesting that targeted rehabilitation may enhance functional outcomes. Conclusions: Enhancing hip flexor strength postoperatively could significantly improve gait recovery in THA patients. These findings support developing individualized rehabilitation strategies to optimize functional outcomes.

Hip joint-preserving strategies for treating osteonecrosis of the femoral head: From nonoperative to operative procedures

Osteonecrosis of the femoral head (ONFH) has an exceedingly high prevalence and disability rate, causing a tremendous socioeconomic burden. The prevalence of ONFH is increasing, while the population of the patients with ONFH is becoming younger. Once the femoral head collapses, treatment becomes difficult and often requires a hip joint replacement, which is not favorable for young patients. Therefore, hip joint-preserving treatments at an early stage of ONFH are particularly important. This study provides a comprehensive review on hip-preserving strategies for treating ONFH, including nonoperative treatments (e.g., protective weight bearing, hyperbaric oxygen, pulsed electromagnetic, extracorporeal shockwave, bisphosphonate, anticoagulants, hypolipidemics, vasodilators, and traditional Chinese medicine) and operative treatments (e.g., core decompression, osteotomy, bone grafting, mesenchymal stem cell transplantation, tantalum rods, and tissue engineering). Nonoperative treatments aim to slow down the progression of the disease and delay the need for joint replacement; however, they usually cannot effectively prevent the progression of the disease, except in cases of small necrosis areas (<10 %). Additionally, nonoperative treatments have unclear mechanisms that require further investigation. In contrast, operative treatments may stop the negative outcomes of necrosis and therefore appear to be more promising. Currently, an emerging area in operative treatments is regenerative medicine, which could promote the generation of bone tissues and blood vessels and restore hip joint function to pre-necrotic levels as much as possible. This review seeks to not only provide an important reference for clinicians when choosing appropriate strategies for treating ONFH but also offer certain guidance for future basic research in developing ONFH treatments.

The translational potential of this article

The incidence of ONFH is increasing, and patients are becoming younger on average. Therefore, the development of hip joint-preserving strategies to treat ONFH at earlier stages is urgently needed, particularly for young patients. However, a comprehensive review is lacking regarding the currently-available hip joint-preserving strategies and their effectiveness. This study is motivated to fill this gap and serve as an important reference for clinicians in choosing appropriate strategies to treat ONFH.

Development and evaluation of a 3D ensemble framework for automatic diagnosis of early osteonecrosis of the femoral head based on MRI: a multicenter diagnostic study

Background

Efficient and reliable diagnosis of early osteonecrosis of the femoral head (ONFH) based on MRI is crucial for the formulation of clinical treatment plans. This study aimed to apply artificial intelligence (AI) to achieve automatic diagnosis and visualization of early ONFH, thereby improving the success rate of hip-preserving treatments.

Method

This retrospective study constructed a multicenter dataset using MRI data of 381 femoral heads from 209 patients with ONFH collected from four institutions (including 239 early ONFH cases and 142 non-ONFH cases). The dataset was divided into training, validation, and internal and external test datasets. This study developed a 3D ensemble framework to automatically diagnose early osteonecrosis of the femoral head based on MRI and utilized 3D Grad-CAM to visualize its decision-making process. Finally, the diagnostic performance of the framework was experimentally evaluated on the MRI dataset and compared with the diagnostic results of three orthopedic surgeons.

Results

On the internal test dataset, the 3D-ONFHNet framework achieved overall diagnostic performance with an accuracy of 93.83%, sensitivity of 89.44%, specificity of 95.56%, F1-score of 87.67%, and AUC of 95.41%. On the two external test datasets, the framework achieved overall diagnostic accuracies of 87.76% and 87.60%, respectively. Compared to three orthopedic surgeons, the diagnostic performance of the 3D-ONFHNet framework was comparable to that of senior orthopedic surgeons and superior to that of junior orthopedic surgeons.

Conclusions

The framework proposed in this study can generate staging results for early ONFH and provide visualizations of internal signal changes within the femoral head. It assists orthopedic surgeons in screening for early ONFH on MRI in a clinical setting, facilitating preoperative planning and subsequent treatment strategies. This framework not only enhances diagnostic efficiency but also offers valuable diagnostic references for physicians.

A nomogram model for predicting preoperative DVT in elderly anemic patients undergoing total hip arthroplasty: a retrospective cohort study

OBJECTIVES

Total hip arthroplasty (THA) is classified as a high-risk surgery for venous thromboembolism (VTE) events, especially in elderly individuals and in cases of anemia. This study aims to uncover independent risk factors for predicting preoperative DVT in elderly anemic patients undergoing THA. Furthermore, it seeks to validate these factors' predictive efficacy in diagnosing DVT, with the goal of facilitating prompt identification and treatment to mitigate associated risks.

METHODS

Clinical information and relevant laboratory test data of preoperative deep vein thrombosis (DVT) in 459 elderly patients with anemia who underwent total hip replacement surgery from January 2018 to June 2024 were retrospectively evaluated. Logistic regression analysis and backward stepwise method were used to detect independent predictors of preoperative DVT diagnosis in elderly patients with anemia who underwent total hip replacement surgery. A nomogram prediction model was established through multivariate logistic regression and subsequently utilized the testing group to validate.

RESULTS

A multivariate logistic regression model was used to analyze the data, Hematocrit (HCT) (Odds ratio (OR) = 0.14, 95% confidence intervals (CI):[0.04,0.52]; P = 0.003), Albumin (ALB) (OR = 0.1, 95% CI:[0.03,0.37]; P = 0.001), Prothrombin Time (PT) (OR = 0.29, 95% CI:[0.1,0.83]; P = 0.02), Fibrin Degradation Products (FDP) (OR = 0.15, 95% CI:[0.05,0.49]; P = 0.002) and lymphocyte/Monocyte ratio (LMR) (OR = 0.28, 95% CI:[0.09,0.87], P = 0.028) were independent predictors for DVT before THA in elderly patients with anemia. The area under the curve (AUC) scores were 0.929 for the training group and 0.896 for the testing group, with calibration curve mean errors of 0.017 and 0.023, respectively. The decision curve analysis (DCA) graph indicates that the developed nomogram was highly practical and advantageous for clinical application.

CONCLUSION

The independent predictors of preoperative DVT in elderly anemic patients undergoing total hip replacement primarily include HCT, ALB, PT, FDP, and LMR at admission, which are easy to obtain and can quickly yield results. Moreover, the nomogram based on HCT, ALB, PT, FDP, and LMR can help clinical doctors evaluate the possibility of DVT formation, thereby accurately and quickly assisting clinical doctors in making better clinical judgments.

Psychometric properties of the Arabic version of the Forgotten Joint Score usage in total hip arthroplasty

BACKGROUND

The ultimate goal of arthroplasty is thought to be the ability to "forget" a joint implant in daily activities. The Forgotten Joint Score (FJS-12), a score system that evaluates how much patients have been able to forget their hip or knee prosthesis, was recently published. It is based on a self-administered questionnaire that consists of 12 items. The major goal of the current study was to validate, adapt, and evaluate a Arabic-language FJS-12 (Ar-FJS-12) version in patients who had undergone total hip replacement (THA).

MATERIALS AND METHODS

The study included 107 patients who underwent THA 1-5 years ago and completed the Ar-FJS. The construct validity of the study was evaluated using the reduced Western Ontario and McMaster Universities Osteoarthritis Index (rWOMAC). To assess the test-retest reliability, 72 people took the Ar-FJS test twice.

RESULTS

Cronbach's alpha (Internal Consistency) of the Ar-FJS-12 was 0.957 and the intraclass correlation coefficient (ICC) was 0.931 indicating high reliability. For construct validity, there was a moderate significant correlation between the Arabic the rWOMAC with r = 0.595. The ceiling effect was 1.9% (n = 2), whereas the floor effect was 1.9% (n = 2).

CONCLUSION

The Arabic version of the FJS-12 valid, reliable tool and can be recommended for patients in Arabic-speaking communities who have undergone hip arthroplasty.

LEVEL OF EVIDENCE

III, validity and reliability study.

Efficacy and safety of acupuncture with moxibustion for knee osteoarthritis: a meta-analysis of randomized controlled trials

BACKGROUND

Osteoarthritis (OA) is prevalent, yet its management remains challenging. This meta-analysis aims to evaluate the efficacy of acupuncture combined with moxibustion versus other standard treatments in patients with knee osteoarthritis (KOA) based on randomized controlled trials (RCTs).

METHODS

Searches were conducted in Ovid MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials to retrieve relevant RCTs. Data on baseline characteristics, treatment efficacy, and adverse events were extracted. The analysis utilized pooled weighted mean differences (WMD) and risk ratios (RR) with 95% confidence intervals (CIs) to assess the superior treatment modality.

RESULTS

A total of 18 RCTs were included. Acupuncture combined with moxibustion demonstrated significant improvement in the visual analog scale (VAS) for pain and the long-term (> 60 weeks) Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores for pain, stiffness, and physical function compared to other treatments. In contrast, short- (< 4 weeks) and mid-term (6-60 weeks) WOMAC outcomes for pain, stiffness, and physical function indicated varied results. The overall efficacy rate also favored the combined therapy significantly in the short- and mid-term evaluations. Notably, this therapy was associated with fewer adverse events.

CONCLUSION

The meta-analysis reveals that acupuncture combined with moxibustion is notably more effective and safer than other treatment modalities for KOA, particularly during mid- and long-term follow-up periods.

Modifications to the Geriatric Nutritional Risk Index Predicts Complications After Total Joint Arthroplasty

BACKGROUND

Preoperative malnutrition is a known risk factor for postoperative complications following total joint arthroplasty (TJA); however, there is scant literature comparing which nutritional index is best at predicting these outcomes. The purpose of this study was to investigate the utility of the Maastricht index, Onodera's Prognostic Nutritional Index, the Geriatric Nutritional Risk index, and a novel, modified Geriatric Nutritional Risk Index (mGNRI) in predicting periprosthetic joint infection (PJI), wound complications (WCs), readmission, and reoperation rates after TJA.

METHODS

A single-center, retrospective cohort study was performed of patients who underwent primary TJA from January 2016 to December 2021. The 90-day preoperative albumin, prealbumin, and total lymphocyte count were collected. Outcome measures were PJI, WC, readmission, and return to the operating room. Youden's index (YI) and Receiver operator characteristic curves were used to determine optimal cutoff points. Multivariable logistic regression was used to adjust for potential confounders, including body mass index, age, and the Charlson comorbidity index.

RESULTS

There were 1,575 patients included in the study. The mGNRI had the greatest accuracy (area under the curve = 0.633; optimal cutoff point = 92.8) in predicting postoperative adverse outcomes. Complication rates were significantly higher in the low mGNRI group (≤ 92.8). When controlled for body mass index, Charlson comorbidity index, and age, the odds of PJI, WC, readmission, and reoperation in patients who had low mGNRI were 6.61 (P = 0.005), 3.04 (P = 0.021), 2.25 (P = 0.020), and 2.75 (P = 0.024), respectively.

CONCLUSIONS

The mGNRI is an easy-to-calculate nutritional index and an excellent predictor of postoperative complications following TJA. The mGNRI outperformed Geriatric Nutritional Risk index, Maastricht index, and Onodera's Prognostic Nutritional Index in predicting postoperative complications. Our results suggest that patients who fall below the mGNRI threshold of 92.8 should be carefully considered for nutritional optimization prior to TJA.

Effectiveness of the video teach-back method in reducing kinesiophobia among patients following unilateral total hip arthroplasty: a quasi-experimental study

BACKGROUND

Kinesiophobia is a significant factor affecting the prognosis of patients with total hip arthroplasty (THA). At present, the primary intervention for kinesiophobia is a 1-way intervention process of healthcare professionals on patients. The video teach-back method uses bidirectional information feedback to ensure high-quality health education. However, little is known about the effect of the video teach-back method on kinesiophobia in patients after unilateral THA.

PURPOSE

To explore the effect of the video teach-back method on the degree of kinesiophobia, hip function, the first ambulation time, hospitalization days, and hospitalization costs in patients after THA.

METHODS

This quasi-experimental study was conducted in the Department of Joint Surgery of a grade III hospital in Changchun City, Jilin Province, targeting patients with kinesiophobia following unilateral THA. A nonconcurrent control design was employed, with participants divided into an intervention group (n = 46) and a control group (n = 45). The control group received conventional care, while the intervention group received video teach-back intervention in addition to traditional care. Within 24 hours post-surgery, patients with a kinesiophobia score of more than 37 completed a general information questionnaire. Primary outcomes, including kinesiophobia and hip function, were assessed on discharge day, 1 and 3 months after surgery, and counted on the day of discharge. Repeated-measures analysis of variance was used to analyze the differences in observation indexes at different time points. Secondary outcomes included the first postoperative ambulation time, hospitalization days, and hospitalization costs.

RESULTS

In comparison between the intervention group and the control group, the kinesiophobia scores and hip function scores of the patients on the discharge date, the first and third months after surgery, had a time effect (P < .001), a group effect (P < .001). The intervention group's reduction in kinesiophobia had a significant effect size (Cohen's d = 0.82) and hip function improvement also demonstrated a significant effect size (Cohen's d = 0.77). The first postoperative ambulation time in the intervention group was significantly earlier than that in the control group (P < .05, Cohen's d = 0.55), with both hospitalization days and costs lower than in the control group; the differences were statistically significant (P < .05).

CONCLUSION

The intervention group showed improvements in kinesiophobia, hip function, first postoperative ambulation time, hospitalization days, and hospitalization costs. These findings suggest that the video teach-back method, as an effective intervention, can be widely applied in clinical practice.

TRIAL REGISTRATION NUMBER

The trial was registered with the Chinese Clinical Trial Registry (registration number: ChiCTR2400079966).

Comparing functional outcomes between 3D printed acetabular cups and traditional prosthetic implants in hip arthroplasty: a systematic review and meta analysis

OBJECTIVE

The primary research aim was to determine if the use of traditional or 3D printed prosthesis resulted in better functional outcome scores in hip arthroplasty.

METHODS

A systematic review and meta-analysis was conducted utilizing the PRISMA 2020 guidelines. Six databases (PubMed, Embase, Scopus, WebOfScience, and Cochrane Library, Google Scholar) were searched yielding 1117 article titles and abstracts. Rayyan.ai was used to detect duplicates (n = 246) and for manual screening for inclusion and exclusion criteria. Included were controlled studies of any publication time that assessed Harris Hip Score (HHS) at baseline and twelve months. Six papers were sought for full text review of which three studies totaling 195 hips met final inclusion.

RESULTS

Mean HHS in the control group went from 38.15 (± 6.02) at baseline to 80.30 (± 4.79) at twelve months follow-up, while the 3D group saw a change from 37.81 (± 5.84) to 90.60 (± 4.49). Significant and large improvements between time points were seen within the control group [p = .02, Cohen's d = 8.57 (1.48, 15.56)] and 3D group [p < 0.01, Cohen's d = 9.18 (3.50, 14.86)]. The HHS score of the 3D group improved by 10.64 points more than the HHS score of the control group, which is a statistically insignificant (p = 0.89) amount.

CONCLUSION

Group differences in pooled mean HHS scores at twelve months follow-up surpassed established minimum differences for clinical importance. High quality research should be further pursued to elucidate these findings.

No need for hip precautions after total hip arthroplasty with posterior approach: A systematic review and meta-analysis

BACKGROUND

Nowadays, total hip arthroplasty (THA) is one of the most successful procedures in the field of orthopedics and trauma. The posterior approach has historically been associated with a higher rate of hip dislocation. To reduce the rate of hip dislocation in the posterior approach, most orthopedic surgeons would recommend hip precautions (HP) for their patients postoperatively based on previous theories. However, recent randomized controlled trials have shown no significant difference in hip dislocation rates with or without HP, in contrast to previous theories. Based on these, this study conducted a meta-analysis of these randomized controlled trials to try to get qualitative conclusions.

METHODS

Randomized controlled trials of HP after THA up to July 28, 2023, were searched in 3 databases, PubMed, Embase, and the Cochrane Library. Data extraction and literature quality assessment were performed by 2 independent authors and extracted hip dislocation, hip disability and Osteoarthritis Outcome Score, joint replacement (HOOS JR) scores over 6 weeks, and time to discontinuation of mobility aids. Stata software and Revman software were used to perform this meta-analysis.

RESULTS

Following screening, 3 papers with a total of 1215 participants were included in the analysis. This meta-analysis showed that there was no statistically significant difference in hip dislocation rates with or without HP after THA undergoing the posterior approach and that the without HP group instead showed better outcomes in terms of HOOS JR scores and time to discontinuation of mobility aids.

CONCLUSION

THA with a posterior approach does not require hip precautions.

All Enabling Technology Is Not Created Equal: Comparing Outcomes of Computer-Assisted Fluoroscopic Navigation Versus Robotic-Assisted Total Hip Arthroplasty

BACKGROUND

Computer-assisted fluoroscopic navigation and robotic technologies aim to optimize implant placement and alignment in primary total hip arthroplasty (THA) to improve patient outcomes. This study uses a retrospective hospital billing database covering 1,300 hospitals to compare the clinical and economic effect of these technologies.

METHODS

The study compared patients undergoing THA with robotic versus computer-assisted fluoroscopic navigation technologies between January 1, 2016, and September 30, 2021, using the Premier Healthcare Database. Primary outcomes were operating room time and readmission rates. Secondary outcomes were length of stay, discharge status, revision rates within 90- and 365-day follow-up, and hospital costs. Baseline covariate differences between the two cohorts were balanced using fine stratification methodology and analyzed using generalized linear models. A sensitivity analysis was conducted using the nearest neighbor matching as the covariate balancing technique.

RESULTS

The cohorts included 4,378 fluoroscopically navigated THA and 10,423 robotic-assisted THA procedures with 90-day follow-up. Operating room time was markedly lower with fluoroscopic navigation compared with robotic-assisted technology (137.74 vs. 156.00 minutes; P < 0.001). Hip-related readmission rates were markedly lower (P < 0.001) for fluoroscopic navigation for both 90- and 365-day follow-up, by 43% and 40% respectively, compared with robotic-assisted technology. Results showed increased discharge ratio to home/home health, reduced length of stay, and lower hospital costs for fluoroscopic navigation compared with robotic-assisted technology. Revision rates were similar for both cohorts.

CONCLUSION

Using computer-assisted fluoroscopic navigation in THA was associated with markedly lower operating room time and readmission rates while also having improved healthcare outcomes and costs compared with robotic-assisted technology.

Hearing the unheard: Fundamentals of acoustic emission signals as predictors of total hip arthroplasty implant loosening

Implant loosening remains a primary cause of failure of total hip arthroplasty1 (THA) and is often detected late, when pain occurs. Acoustic emission2 (AE) analysis is a promising method for early loosening detection, on the supposition that relative movements at the bone-implant interface induce detectable AE signals. To distinguish loosening-induced AE signals from those of stable THA components in vitro investigations are necessary. Substituting human with animal bone for such testing could enable simplified and cost-effective sample preparation. The aim of this study was to investigate whether AE signals differ between bone tissues of different species. AE signals generated by relative movements between TiAl6V4 and human, bovine, and porcine cortical bone were investigated. Per species, 125 movements were analyzed, with 26 AE features identified for each movement. The most important time and frequency features of AE signals from human bone differed significantly from those of both animal species. Signals of human origin were longer and exhibited higher rise time. The main frequency components of human AE signals were in a lower frequency range, with a centroid frequency of 113.7 kHz. Based on these differences, it is not advisable to replace human cortical bone with animal bone for AE-related in vitro studies.

Comparison of Biocompatibility of 3D-Printed Ceramic and Titanium in Micropig Ankle Hemiarthroplasty

BACKGROUND

Ankle arthritis is a common degenerative disease that progresses as cartilage damage in the lower tibia and upper talus progresses, resulting in loss of joint function. In addition to typical arthritis, there is also structural bone loss in the talus due to diseases such as talar avascular necrosis. Total talus replacement surgery is the procedure of choice in end-stage ankle arthritis and consists of a tibial, talar component and an insert. However, in cases of severe cartilage and bone damage to the talar bone with less damage to the tibial cartilage, a talar component hemiarthroplasty may be considered. Although the application of total talus replacement surgery using ceramics has been studied, reports on the application of metal 3D printing technology are limited. We aimed to investigate the feasibility of partial talar components using ceramic and titanium 3D printing technology in terms of biocompatibility and stability through animal experiments.

METHODS

Preoperative 3D CT was acquired and converted to STL files to fabricate a partial talus component for ankle hemiarthroplasty using ceramic and titanium. Six minipigs with an average age of 17 months were implanted with three ceramic (C-group) and three titanium talar components (T-group) in the hind limb ankle joint. The surgery was performed under anesthesia in a sterile operating room and was performed by two experienced foot and ankle specialist orthopedic surgeons. Blood analysis and CT were performed before surgery and every month for 3 months after surgery to assess the extent of inflammatory response and physical stability, sacrifices were performed 3 months after surgery, and H&E staining and micro-CT analysis were performed to compare histological biocompatibility. A grading score was calculated to semi-quantitative assess and compare the two groups.

RESULTS

In the postsurgical evaluation, blood analysis revealed that both groups had increased white blood cell counts on the postoperative day after surgery. The white blood cell count increased more in the titanium group (1.85-fold) than in the ceramic group (1.45-fold). After 3 months, all values normalized. During the study, CT analysis confirmed that all artificial samples were displaced from their initial positions. In micro-CT analysis, the adhesive tissue score of the ceramic artificial sample was better than that of the titanium sample (average threshold = 3027.18 ± 405.92). In histologic and grading scores for the inflammatory reactions, the average inflammation indices of the ceramic and titanium groups were 2.0 and 1.21, respectively. Also, the average grade score confirmed based on the results of fibrous tissue proliferation and new blood vessels was 18.4 in the ceramic application group and 12.3 in the titanium application group.

CONCLUSIONS

In conclusion, both titanium and ceramics have excellent biocompatibility for artificial joints, and ceramic materials can be used as novel artificial joints. Further research on the strength and availability of these ceramics is required.

Ulcerative Colitis Patients Are at Increased Risk for Adverse Events Following Total Hip Arthroplasty

BACKGROUND

Patients who have the autoinflammatory bowel disease ulcerative colitis (UC) may become candidates for total hip arthroplasty (THA). Having UC may predispose patients to postoperative adverse events, but it remains unclear if these events are related more to the disease process itself or perhaps related to the medications used to treat the condition.

METHODS

Patients undergoing THA were identified from a large administrative dataset. Those who did not have and those who had UC were matched 4:1 based on patient age, sex, and the Elixhauser Comorbidity Index. Matched THA patients who did not have UC (n = 19,482) and those who had UC (n = 4,874) were identified. The matched groups were compared regarding 90-day adverse and five-year survival. Further analyses were performed based on classes of medications.

RESULTS

Controlling for patient age, sex, and Elixhauser Comorbidity Index, UC patients were at significantly higher odds of 90-day adverse events: any (odds ratio [OR]: 1.59), severe (OR: 1.72), and minor (OR: 1.63) (all P < 0.001). Despite this, no differences in 5-year survival were identified. Relative to those who did not have UC, there were increasing odds of any adverse event based on the potency of related medications: no corticosteroids/immunomodulators/5-aminosalicylic acid (5-ASA) (OR: 1.42), corticosteroids only (OR: 1.58), 5-ASA ± corticosteroids OR (1.72), and immunomodulators ± corticosteroids (OR: 1.74, all P < 0.001).

CONCLUSIONS

Total hip arthroplasty patients who have UC were at higher odds for 90-day postoperative adverse events relative to those who did not have UC, and this risk was even greater for those on defined classes of medications. Total hip arthroplasty patients who have UC bear specific considerations, and surgeons must carefully consider and manage the patient's medication regimen in the perioperative period of the THA.

Feasibility of automated surveillance of implantable devices in orthopaedics via clinical data warehouse: the Studio study

BACKGROUND

Total hip, knee and shoulder arthroplasties (THKSA) are increasing due to expanding demands in ageing population. Material surveillance is important to prevent severe complications involving implantable medical devices (IMD) by taking appropriate preventive measures. Automating the analysis of patient and IMD features could benefit physicians and public health policies, allowing early issue detection and decision support. The study aimed to demonstrate the feasibility of automated cohorting of patients with a first arthroplasty in two hospital data warehouses (HDW) in France.

METHODS

The study included adult patients with an arthroplasty between 2010 and 2019 identified by 2 data sources: hospital discharge and pharmacy. Selection was based on the health insurance thesaurus of IMDs in the pharmacy database: 1,523 distinct IMD references for primary THSKA. In the hospital discharge database, 22 distinct procedures for native joint replacement allowing a matching between IMD and surgical procedure of each patient selected. A program to automate information extraction was implemented in the 1st hospital data warehouse using natural language processing (NLP) on pharmacy labels, then it was then applied to the 2nd hospital.

RESULTS

The e-cohort was built with a first arthroplasty for THKSA performed in 7,587 patients with a mean age of 67.4 years, and a sex ratio of 0.75. The cohort involved 4,113 hip, 2,630 knee and 844 shoulder surgical patients. Obesity, cardio-vascular diseases and hypertension were the most frequent medical conditions.

DISCUSSION

The implementation of an e-cohort for material surveillance will be easily workable over HDWs France wild. Using NLP as no international IMD mapping exists to study IMD, our approach aims to close the gap between conventional epidemiological cohorting tools and bigdata approach.

CONCLUSION

This pilot study demonstrated the feasibility of an e-cohort of orthopaedic devices using clinical data warehouses. The IMD and patient features could be studied with intra-hospital follow-up and will help analysing the infectious and unsealing complications.

Hip contact force pathways in total hip replacement differ between patients and activities of daily living

One of the main causes of implant failure and revision surgery in total hip replacement (THR) is aseptic loosening often caused by the accumulation of wear debris arising between the contact surfaces of the acetabular cup and femoral head during activities of daily living (ADL's). However, limited information is available regarding the contact force pathways between these two surfaces during specific ADL's. In this study, through musculoskeletal modelling, we aimed to estimate the orientation of the hip contact force pathway on the acetabular cup. One hundred and thirty-two THR patients underwent motion capture analysis whilst undertaking locomotor and non-locomotor ADL's. Musculoskeletal simulations were performed to calculate contact force pathways using inverse dynamics analysis. We then qualitatively compared differences in the contact force pathways between patients and between ADL's. Walking resulted in a typical figure-of-eight pattern, with the peak contact forces occurring in the superior-anterior area of the cup. The non-locomotive activities such as stand up, sit down and squat had a more linear shape, spanning across the superior-posterior quarter of the cup. Our results showed a large inter-patient variability in the shape and location of the contact force pathway. There is a distinct difference in the location and shape of the pathway between locomotor and non-locomotor activities and this could result in different wear accumulations. These results could enhance our understanding why revision rates vary across the population and could inform the development of personalised implant design.

Bone allograft impregnated with tobramycin and vancomycin delivers antibiotics in high concentrations for prophylaxis against bacteria commonly associated with prosthetic joint infections

Local delivery of antibiotics as prophylaxis for prosthetic joint infections (PJIs) is frequently used during total hip replacement surgery. Morselized bone allograft impregnated with vancomycin and tobramycin (TobraVanc) could provide effective prophylaxis against bacteria commonly associated with PJIs. In this study, the concentrations of antibiotics released by bone allograft impregnated with TobraVanc were determined by using an in vitro bioassay system entailing measuring inhibition zone diameters caused by antibiotic-impregnated bone chips cast in agar against standard curves. The concentrations were determined in samples of TobraVanc-impregnated bone graft taken before and after the application of the bone graft in the patients undergoing acetabular revision surgery. Antibiotic-impregnated bone grafts, sampled prior to application in the patient, delivered antibiotics in the concentration ranges of 730-9,800 mg/L for tobramycin and 1,300-11,000 mg/L for vancomycin. Samples taken after application in the patient released lower concentrations of tobramycin (490-1,900 mg/L; P < 0.01) and vancomycin (3,000-5,100 mg/L; P < 0.05); however, these concentrations remained well above the tobramycin minimum inhibitory concentrations (MICs) for investigated, highly tobramycin-resistant Staphylococcus epidermidis strains (MICs > 256 mg/L). At the tested concentrations, bone graft material mixed with TobraVanc delivered antibiotics in potent concentrations above the MICs for bacteria causing PJIs. Clinical trials are needed to evaluate the efficacy and risk of TobraVanc-impregnated bone graft as a prophylactic agent for patients undergoing hip replacement surgery.IMPORTANCEAntibiotic prophylaxis is the cornerstone of successful joint replacement surgery, reducing the risk for the dreaded complication of prosthetic joint infection (PJI) to roughly 0.5%-2% in standard total hip replacement (THR). In addition to systemic antibiotics, antibiotics added locally have the potential to reduce the PJI risk even further, because of the high concentrations that can be achieved in the joint with limited risk for systemic toxicity. The results in the current study show that bone chips impregnated with a combination of tobramycin and vancomycin (TobraVanc) release antibiotics in concentrations that are potent against common bacteria causing PJIs. Especially in high-risk patients, our results support the prophylactic use of TobraVanc in hip replacement surgery requiring the use of a bone graft. A clinical study testing the efficacy of TobraVanc-impregnated bone graft in reducing the incidence of PJI in hip replacement surgery is currently ongoing (EudraCT: 2021-001708-14).

Outcomes of Hip Arthroplasty in Patients with Preoperative Thrombocytopenia

Background

Thrombocytopenia is a condition where platelet counts are below the normal range (< 150 × 103/µL), resulting in a higher risk of bleeding and affecting the results of hip arthroplasty. We assessed the impact of preoperative platelet counts on the clinical results of patients who underwent hip arthroplasty.

Methods

Between April 2003 and March 2023, 437 patients (451 hips), who had preoperative thrombocytopenia of less than 150 × 103/µL platelets, underwent hip arthroplasty. Preoperative platelet levels were categorized into severe thrombocytopenia (< 50 × 103/µL) and non-severe thrombocytopenia (50-149 × 103/µL). Total blood loss, operation time, requirement of transfusion, amount of transfusion, duration of surgical wound oozing, length of hospital stay, mortality rate at 1 year after surgery, and any complication were compared between the 2 groups.

Results

No notable differences were observed in the surgery time or the total amount of blood loss between the groups. The requirement of transfusion and the amount of transfused blood were higher in the severe thrombocytopenia group. Prolonged oozing was found in around 18% in both groups, while periprosthetic joint infections occurred in 3 of the non-severe thrombocytopenia group. No significant difference was noted in the duration of hospital stay (25.6 ± 18.3 days vs. 19.4 ± 16.6 days, p = 0.067) and 1-year mortality (22.2% vs. 11.8%, p = 0.110).

Conclusions

Hip arthroplasties are safe for patients with low platelet counts and do not lead to prolonged hospital stays. On the other hand, patients with severe thrombocytopenia tend to need blood transfusions more frequently than those with less severe thrombocytopenia.

Prediction of intraoperative press-fit stability of the acetabular cup in total hip arthroplasty using radiomics-based machine learning models

BACKGROUND

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).

METHODS

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.

RESULTS

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.

CONCLUSION

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.

Association Between Periprosthetic Joint Infection and Mortality Following Primary Total Hip Arthroplasty

BACKGROUND

Periprosthetic joint infection (PJI) remains a dreaded and unpredictable complication after total hip arthroplasty (THA). In addition to causing substantial morbidity, PJI may contribute to long-term mortality risk. Our objective was to determine the long-term mortality risk associated with PJI following THA.

METHODS

This population-based, retrospective cohort study included adult patients (≥18 years old) in Ontario, Canada, who underwent their first primary elective THA for arthritis between April 1, 2002, and March 31, 2021. The primary outcome was death within 10 years after the index THA. Mortality was compared between propensity-score-matched groups (PJI within 1 year after surgery versus no PJI within 1 year after surgery) with use of survival analyses. Patients who died within 1 year after surgery were excluded to avoid immortal time bias.

RESULTS

A total of 175,432 patients (95,883 [54.7%] women) with a mean age (and standard deviation) of 67 ± 11.4 years underwent primary THA during the study period. Of these, 868 patients (0.49%) underwent surgery for a PJI of the replaced joint within 1 year after the index procedure. After matching, patients with a PJI within the first year had a significantly higher 10-year mortality rate than their counterparts (11.4% [94 of 827 patients] versus 2.2% [18 of 827 patients]; absolute risk difference, 9.19% [95% confidence interval (CI), 6.81% to 11.6%]; hazard ratio, 5.49 [95% CI, 3.32 to 9.09]).

CONCLUSIONS

PJI within 1 year after surgery is associated with over a fivefold increased risk of mortality within 10 years. The findings of this study underscore the importance of prioritizing efforts related to the prevention, diagnosis, and treatment of PJIs.

LEVEL OF EVIDENCE

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

Mid-Term Migration Pattern of a Cemented Collared Anatomical Stem-A Retrospective Study Using EBRA-FCA

Background: Aseptic loosening is one of the leading causes of stem revision. Einzel Bild Röntgen Analyse-Femoral Component Analysis allows for the detection of distal stem migration, which is used as a predictive factor for implant longevity. This study aims to demonstrate the migration behavior of a cemented collared anatomical stem. Methods: This study retrospectively examined all patients who received a cemented Lubinus SP II stem (Waldemar Link, Hamburg, Germany) between 2003 and 2019. We used the EBRA-FCA software (University of Innsbruck, Austria) to determine the migration patterns and thoroughly examined the patients' medical histories. In addition, the potential influence of femoral configuration and BMI on the migration behavior was assessed. Results: This study included 61 patients (48 females and 13 males) with a total of 61 stems that met our inclusion criteria. The mean age at surgery was 76 years (ranging from 30 to 93 years). According to EBRA-FCA migration analysis, a median subsidence of 0.7 mm was observed at 24 months and at the final follow-up (median 78 months). Distal stem migration was significantly higher at the 6-month time point in patients with Dorr type A femurs compared to Dorr type B femurs (p = 0.016). Body mass index (BMI) had no significant effect on stem migration. Conclusions: The measured subsidence of the Lubinus SP 2 stem using EBRA-FCA was below established thresholds, indicating excellent long-term outcomes. Although there was significantly increased subsidence in Dorr type A femurs during the initial 6 months, thereafter, no statistically significant difference was observed compared to Dorr type B femurs.

Time to Achieve the Minimal Clinically Important Difference in Primary Total Hip Arthroplasty: Comparison of Anterior and Posterior Surgical Approaches

BACKGROUND

Controversy remains over outcomes between total hip arthroplasty approaches. This study aimed to compare the time to achieve the minimal clinically important difference (MCID) for the Hip Disability and Osteoarthritis Outcome Score-Physical Function Short Form (HOOS-PS) and the Patient-Reported Outcomes Measurement Information System (PROMIS) Global-Physical for patients who underwent anterior and posterior surgical approaches in primary total hip arthroplasty.

METHODS

Patients from 2018 to 2021 with preoperative and postoperative HOOS-PS or PROMIS Global-Physical questionnaires were grouped by approach. Demographic and MCID achievement rates were compared, and survival curves with and without interval-censoring were used to assess the time to achieve the MCID by approach. Log-rank and weighted log-rank tests were used to compare groups, and Weibull regression analyses were performed to assess potential covariates.

RESULTS

A total of 2,725 patients (1,054 anterior and 1,671 posterior) were analyzed. There were no significant differences in median MCID achievement times for either the HOOS-PS (anterior: 5.9 months, 95% confidence interval [CI]: 4.6 to 6.4; posterior: 4.4 months, 95% CI: 4.1 to 5.1, P = .65) or the PROMIS Global-Physical (anterior: 4.2 months, 95% CI: 3.5 to 5.3; posterior: 3.5 months, 95% CI: 3.4 to 3.8, P = .08) between approaches. Interval-censoring revealed earlier times of achieving the MCID for both the HOOS-PS (anterior: 1.509 to 1.511 months; posterior: 1.7 to 2.3 months, P = .87) and the PROMIS Global-Physical (anterior: 3.0 to 3.1 weeks; posterior: 2.7 to 3.3 weeks, P = .18) for both surgical approaches.

CONCLUSIONS

The time to achieve the MCID did not differ by surgical approach. Most patients will achieve clinically meaningful improvements in physical function much earlier than previously believed.

LEVEL OF EVIDENCE

Level III, Retrospective Comparative Study.

Monte Carlo-based in-depth morphological analysis of medullary cavity for designing personalized femoral stem

Background

The design of femoral stem prostheses requires a precise understanding of the femoral marrow cavity. Traditional measurements of morphological parameters in the upper femur, particularly the medullary cavity and cortical region, are primarily based on coronal and sagittal axes, which may not fully capture the true three-dimensional structure of the femur.

Methods

Propose a Monte Carlo-based method for a more comprehensive analysis of the femoral marrow cavity, using CT scans of femurs from a selected group of patients. The study aimed to define and calculate anatomically semantic morphological parameters to enhance the understanding of the femoral marrow cavity's anatomical morphological changes, ultimately improving the design and clinical selection of femoral stem prostheses. To enhance the accuracy of femoral stem prosthesis design, this study aims to develop a Monte Carlo-based method for a more comprehensive analysis of the femoral marrow cavity. The proposed method transforms the non-random problem of determining cross-sectional size into a random issue, allowing for the calculation of the size of the medullary cavity and cortical region. Anatomically semantic morphological parameters are then defined, calculated, and analyzed.

Results

The experimental results indicate that the newly defined parameters complement existing ones, providing a more rational scientific basis for understanding the anatomical morphological changes of the femoral marrow cavity.

Conclusion

This research offers essential scientific theoretical support for improved morphologic research, design, and clinical selection of femoral stem prostheses. It holds significant importance and application value in clinical practice, contributing to a more accurate and comprehensive understanding of femoral anatomy for prosthetic design.

Functional assessment in patients undergoing total hip arthroplasty

Aims

Conventional patient-reported surveys, used for patients undergoing total hip arthroplasty (THA), are limited by subjectivity and recall bias. Objective functional evaluation, such as gait analysis, to delineate a patient's functional capacity and customize surgical interventions, may address these shortcomings. This systematic review endeavours to investigate the application of objective functional assessments in appraising individuals undergoing THA.

Methods

The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were applied. Eligible studies of THA patients that conducted at least one type of objective functional assessment both pre- and postoperatively were identified through Embase, Medline/PubMed, and Cochrane Central database-searching from inception to 15 September 2023. The assessments included were subgrouped for analysis: gait analysis, motion analysis, wearables, and strength tests.

Results

A total of 130 studies using 15 distinct objective functional assessment methods (FAMs) were identified. The most frequently used method was instrumented gait/motion analysis, followed by the Timed-Up-and-Go test (TUG), 6 minute walk test, timed stair climbing test, and various strength tests. These assessments were characterized by their diagnostic precision and applicability to daily activities. Wearables were frequently used, offering cost-effectiveness and remote monitoring benefits. However, their accuracy and potential discomfort for patients must be considered.

Conclusion

The integration of objective functional assessments in THA presents promise as a progress-tracking modality for improving patient outcomes. Gait analysis and the TUG, along with advancing wearable sensor technology, have the potential to enhance patient care, surgical planning, and rehabilitation.

Preoperative Laboratory Values Predicting Periprosthetic Joint Infection in Morbidly Obese Patients Undergoing Total Hip or Knee Arthroplasty

BACKGROUND

Morbidly obese patients are an ever-growing high-risk population undergoing total hip arthroplasty (THA) and total knee arthroplasty (TKA) for end-stage osteoarthritis. This study sought to identify preoperative laboratory values that may serve as predictors of periprosthetic joint infection (PJI) in morbidly obese patients undergoing THA or TKA.

METHODS

All morbidly obese patients with preoperative laboratory data before undergoing primary elective TKA or THA were identified using the Premier Healthcare Database. Patients who developed PJI within 90 days after surgery were compared with patients without PJI. Laboratory value thresholds were defined by clinical guidelines or primary literature. Univariate and multivariable regression analyses were utilized to assess the association between PJI and preoperative laboratory values, including total lymphocyte count, neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR), monocyte-lymphocyte ratio (MLR), systemic immune-inflammation index (SII), albumin level, platelet count, albumin-globulin ratio, hemoglobin level, and hemoglobin A1c.

RESULTS

Of the 6,780 patients identified (TKA: 76.67%; THA: 23.33%), 47 (0.69%) developed PJI within 90 days after surgery. The rate of PJI was 1.69% for patients with a hemoglobin level of <12 g/dL (for females) or <13 g/dL (for males), 2.14% for those with a platelet count of <142,000/µL or >417,000/µL, 1.11% for those with an NLR of >3.31, 1.69% for those with a PLR of >182.3, and 1.05% for those with an SII of >776.2. After accounting for potential confounding factors, we observed an association between PJI and an abnormal preoperative NLR (adjusted odds ratio [aOR]: 2.38, 95% confidence interval [CI]: 1.04 to 5.44, p = 0.039), PLR (aOR: 4.86, 95% CI: 2.15 to 10.95, p < 0.001), SII (aOR: 2.44, 95% CI: 1.09 to 5.44, p = 0.029), platelet count (aOR: 3.50, 95% CI: 1.11 to 10.99, p = 0.032), and hemoglobin level (aOR: 2.62, 95% CI: 1.06 to 6.50, p = 0.038).

CONCLUSIONS

This study identified preoperative anemia, abnormal platelet count, and elevated NLR, PLR, and SII to be associated with an increased risk of PJI among patients with a body mass index of ≥40 kg/m 2 . These findings may help surgeons risk-stratify this high-risk patient population.

LEVEL OF EVIDENCE

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

Bone mineral density changes around the stem correlate with stress changes after total hip arthroplasty: A study using thermoelastic stress analysis

Purpose

Thermoelastic stress analysis (TSA) was used to evaluate stress changes over the entire surface of a specimen. This study aimed to assess the relationship between femoral stress distribution, analysed using TSA and changes in bone mineral density (BMD) after total hip arthroplasty (THA).

Methods

Stress changes in the simulated bone before and after taper-wedge stem insertion were measured using the TSA. Stress changes were compared with BMD changes around the stem 1 year after surgery in a THA patient (58 hips) with the same taper-wedge stem. Subsequently, we compared the correlation between stress changes and BMD changes.

Results

TSA revealed significant stress changes before and after stem insertion, with prominent alterations in the proximal medial region. The BMD changes at 1 year post-THA exhibited a 15%-25% decrease in the proximal zones, while Zones 2-6 showed a -6% to 3% change. Notably, a strong positive correlation (0.886) was found between the stress change rate and BMD change rate.

Conclusions

This study demonstrated a high correlation between femoral stress distribution assessed using TSA and subsequent BMD changes after THA. The TSA method offers the potential to predict stress distribution and BMD alterations postsurgery, aiding in implant development and clinical assessment. Combining TSA with finite element analysis could provide even more detailed insights into stress distribution.

Level of Evidence

Case series (with or without comparison).

A novel intraoperative acetabular reaming center locating method in total hip arthroplasty for Crowe type IV developmental dysplasia of the hip: a retrospective cohort study

PURPOSE

Although the principles of hip reconstruction are consistent, due to lack of reliable anatomical landmarks, how to decide the acetabular cup reaming centre intraoperatively in Crowe IV patients with developmental dysplasia of the hip (DDH) remains unclear. This study aims to address this question.

METHODS

Fifty-eight Crowe IV patients were enrolled from 2017 to 2019. By examining our previous clinical data, we analyzed the anatomical morphology of Crowe IV acetabulum and proposed a method of locating intraoperative reaming centering for implantation of a standard-sized acetabular cup, which is the upper two thirds of the posterior border of the true acetabulum. All patients included in this study were reamed according to this method. The average postoperative follow-up was 4.1 years (3-5 years). The position of the centre of rotation (COR), cup coverage (CC), and optimal range of joint motion (ROM) were examined by 3D computer simulation measurement. Postoperative complications and hip Harris score were collected and analyzed.

RESULTS

The morphology of the type IV DDH true acetabulum was mostly triangular. The intraoperative reaming centre were centered on the upper two thirds of the posterior border of the true acetabulum. The postoperative 3D CC was 80.20% ± 7.63% (64.68-90.24%, 44-48-mm cup size). The patients' mean Harris score improved from 39.7 ± 20.4 preoperatively to 91.5 ± 8.12 at the last follow-up.

CONCLUSION

Our study demonstrated that satisfactory CC and clinical results could be achieved by implanting a standard-sized cup with the reaming centre on the upper two thirds of the posterior border of the true acetabulum.

Artificial intelligence technology improves the accuracy of preoperative planning in primary total hip arthroplasty

OBJECTIVE

Successful total hip arthroplasty relies on accurate preoperative planning. However, the conventional preoperative planning, a two-dimensional method using X-ray template, has shown poor reliability of predicting component size. To our knowledge, artificial intelligence technology assisted three-dimensional preoperative planning is promising to improve the accuracy of preoperative planning but there is a dearth of clinical evidence. Therefore, in this study we compared the prediction accuracy of these two maneuvers.

METHODS

We conducted a prospective study consisting of 117 consecutive patients who underwent a primary cementless total hip arthroplasty to compare the prediction accuracy of these two methods. The two-dimensional and artificial intelligence assisted three-dimensional planning results of the same patient were compared with the definitive implant size respectively.

RESULTS

The prediction accuracy of artificial intelligence assisted three-dimensional planning for cup and the stem sizes were 66.67% (78/117) and 65.81% (77/117), two-dimensional planning was 30.77% (36/117) and 37.61% (44/117) (p < 0.05). There were poor prediction results of two-dimensional planning in patients with hip dysplasia (p = 0.004, OR = 7.143) and excessive femoral anteversion (p = 0.012, OR = 1.052), meanwhile the failure risk of stem side two-dimensional planning increased as patients got older (p = 0.003, OR = 1.118). The accuracy of artificial intelligence assisted three-dimensional planning cannot be affected by above factors.

CONCLUSIONS

We confirmed that artificial intelligence assisted three-dimensional preoperative planning showed higher accuracy and stability than two-dimensional preoperative planning in primary cementless total hip arthroplasty. We believe artificial intelligence assisted three-dimensional preoperative planning technology provides surgeons a new reliable choice and offers advantages whether in simple or complicated cases.

Post-Arthroplasty Spatiotemporal Gait Parameters in Patients with Hip Osteoarthritis or Developmental Dysplasia of the Hip: An Observational Study

Total hip arthroplasty (THA) is a preferred treatment for primary osteoarthritis (OA) or secondary degenerative arthropathy due to developmental hip dysplasia (DDH). Gait analysis is considered a gold standard for evaluating post-arthroplasty walking patterns. This study compared post-THA spatiotemporal gait parameters (SGPs) between OA and DDH patients and explored correlations with demographic and clinical variables. Thirty patients (15 per group) were recorded during gait and their SGPs were analyzed. Functionality was evaluated with the Oxford Hip Score (OHS). The OA patients were significantly older than DDH patients (p < 0.005). Significant and moderate to strong were the correlations between SGPs, age, and four items of the OHS concerning hip pain and activities of daily life (0.31 < Pearson's r < 0.51 all p < 0.05). Following THA, both groups exhibited similar levels of the examined gait parameters. Post-arthroplasty SGPs and OHS correlations indicate limitations in certain activities. Given the absence of pre-operative data and the correlation between age and SGPs and OHS, ANCOVA testing revealed that age adjusts OHS and SGP values, while pre-operative diagnosis has no main effect. These findings indicate that hip OA or DDH do not affect postoperative SGPs and patients' functionality. Future studies should examine both kinematic and kinetic data to better evaluate the post-THA gait patterns of OA and DDH patients.

The emerging role of the semaphorin family in cartilage and osteoarthritis

In the pathogenesis of osteoarthritis, various signaling pathways may influence the bone joint through a common terminal pathway, thereby contributing to the pathological remodeling of the joint. Semaphorins (SEMAs) are cell-surface proteins actively involved in and primarily responsible for regulating chondrocyte function in the pathophysiological process of osteoarthritis (OA). The significance of the SEMA family in OA is increasingly acknowledged as pivotal. This review aims to summarize the mechanisms through which different members of the SEMA family impact various structures within joints. The findings indicate that SEMA3A and SEMA4D are particularly relevant to OA, as they participate in cartilage injury, subchondral bone remodeling, or synovitis. Additionally, other elements such as SEMA4A and SEMA5A may also contribute to the onset and progression of OA by affecting different components of the bone and joint. The mentioned mechanisms demonstrate the indispensable role of SEMA family members in OA, although the detailed mechanisms still require further exploration.

Patients' expectations surrounding revision total hip arthroplasty: a literature review

BACKGROUND

Revision total hip arthroplasties (RTHA) are associated with a higher complication rate than primary total hip arthroplasties (THA), and therefore it is important for patients to have realistic expectations regarding outcomes. The aim of this literature review was to gather and summarize the available evidence on patients' expectations following RTHA.

METHODS

A literature search was conducted in PubMed, PsycINFO, Cochrane, Google Scholar, Web of Science and Embase from inception to November 2023. Articles assessing patient expectations for RTHA were included. Methodological quality was assessed by two independent reviewers using the National Heart, Lung and Blood Institute (NIH) study quality assessment tool for observational cohort and cross-sectional studies. A qualitative analysis was performed involving the summarization of study characteristics and outcomes.

RESULTS

The search strategy generated 7,450 references, of which 5 articles met the inclusion criteria. Methodological quality scores ranged from 7-10. Patients had high expectations concerning future walking ability, pain and implant longevity relative to actual postoperative outcomes. A significant positive correlation was found between fulfilled expectations of pain and walking ability and patient satisfaction (r = 0.46-0.47). Only two studies assessed the fulfillment of patient expectations. Great variability was seen in the measurement of expectations.

CONCLUSION

Patients undergoing RTHA appeared to have high expectations for pain and functionality compared to postoperative outcomes. However, there was a paucity of high-quality data in this area, limiting the accuracy of the conclusion. Further research is needed, that emphasizes developing a sound theoretical framework for expectations, allowing for the consistent implementation of valid measurement tools for patient expectations.

A Comprehensive Approach to PROMs in Elective Orthopedic Surgery: Comparing Effect Sizes across Patient Subgroups

Background: There is limited knowledge regarding the comparative patient-reported outcomes (PROMs) and effect sizes (ESs) across orthopedic elective surgery. Methods: All patient data between January 2020 and December 2022 were collected, and treatment outcomes assessed as a PROM difference between baseline and one-year follow-up. The cohort was divided into subgroups (hand, elbow, shoulder, spine, hip, knee, and foot/ankle). The PROM ESs were calculated for each patient separately, and patients with ES > 0.5 were considered responders. Results: In total, 7695 patients were operated on. The mean ES across all patient groups was 1.81 (SD 1.41), and the largest ES was observed in shoulder patients and the smallest in hand patients. Overall, shoulder, hip, and knee patients had a larger ES compared to hand, spine, and foot/ankle patients (p < 0.0001). The proportion of positive responders ranged between 91-94% in the knee, shoulder, and hip, and 69-70% in the hand, spine, and foot/ankle subgroups. Conclusions: The ESs are generally high throughout elective orthopedic surgery. However, based on our institutional observations, shoulder, hip, and knee patients experience larger treatment effects compared to hand, spine, and foot/ankle patients, among whom there are also more non-responders. The expected treatment outcomes should be clearly communicated to patients when considering elective surgery. Because of the study limitations, the results should be approached with some caution.

Early Postoperative Change in Hip Rotation Angle and Factors Contributing to It for Patients Undergoing Total Hip Arthroplasty

OBJECTIVE

A possible impairment in hip proprioception after total hip arthroplasty (THA) has been an issue of concern. The aims of this study were to investigate the extent of early postoperative change in standing hip rotation angle (HRAng) in patients with osteoarthritis (OA) undergoing THA and to consider a possible mechanism behind this.

MATERIALS AND METHODS

A total of 82 hips (82 patients; 63 women and 19 men) undergoing unilateral primary THA with total capsulectomy were included. We characterized the standing HRAng and internal/external range of motion (ROM) in the prone position before THA and 2 weeks after THA. Acetabular/cup and femoral/stem anteversion, combined anteversion (CA), and leg length discrepancy were also characterized. Correlations were examined postoperatively between the HRAng and the other analyzed variables.

RESULTS

The median standing HRAng showed a significant internal shift from external to more medial position (6.3° to 1.7°) 2 weeks after THA (P<.0001). The postoperative change in standing HRAng was significantly negatively correlated with the difference between the postoperative femoral anteversion and the stem anteversion (rs=-0.429, P<.0001) and with the pre- to postoperative change in CA (rs=-0.3012, P=.0063).

CONCLUSION

This study demonstrated that the extent of the rotational shift of the distal femur toward medial direction was significantly associated with increasing stem anteversion and CA. This phenomenon can be interpreted as a compensatory mechanism for maintaining the relative positional relationship between the pelvis and the proximal femur using proprioception. Therefore, we conclude that the extracapsular/extra-articular components may be prominent determinants of joint position sense. [Orthopedics. 2024;47(3):e114-e118.].

Comparative analysis of the quality of life regarding patients who underwent hip replacement in public versus private hospitals in Hungary

The study aimed to investigate the impact of hip replacement surgery on the quality of life and to compare the outcomes by sociodemographic and surgical data in Hungarian public and private hospitals. Patients were selected at the Department of Orthopaedics (Clinical Centre, University of Pécs) and at the Da Vinci Private Clinic in Pécs. Patients completed the SF-36 and Oxford Hip Score (OHS) questionnaires before the surgery, 6 weeks and 3 months later. We also evaluated socio-demographic data, disease and surgical conditions. The research involved 128 patients, 60 patients in public, 68 patients in private hospital. Despite the different sociodemographic characteristics and surgical outcomes of public and private healthcare patients, both groups had significantly improved the quality of life 3 months after hip replacement surgery measured by OHS and SF-36 physical health scores (p < 0.001). In the mental health score, only the patients of the private health sector showed a significant improvement (p < 0.001). The extent of improvement did not differ between the two healthcare sectors according to the OHS questionnaire (p = 0.985). While the SF-36 physical health score showed a higher improvement for public patients (p = 0.027), the mental health score showed a higher improvement for private patients (p = 0.015).

What is the most appropriate comparator group to use in assessing the performance of primary total hip prostheses within the community?

BACKGROUND

There are variations in the performance of individual prostheses used in hip replacements. Some of which have unexpectedly higher revision rates - outliers. The Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR) has established a standardised multi-stage approach for identifying these devices. This is done by comparing the revision rates of individual prostheses to all other prostheses in class, with the exception of large head metal-on-metal (LHMoM) prostheses. However, improvements in device design and performance over time have required a need to reconsider the comparator group. This study aimed to identify a more specific comparator to better reflect contemporary surgical practice.

METHODS

The time to first revision was estimated on the data of 413,417 primary total conventional hip replacements undertaken for osteoarthritis (OA) from 01 January 2003 to 31 December 2019. Survivorship analyses with stepwise exclusions were undertaken. The first exclusion was LHMoM, followed by other non-modern bearing surfaces (defined as all the bearing couples except metal or ceramic heads on cross-linked polyethylene and mixed ceramic-on-ceramic), and then devices with modular neck-stem design or used for specific purposes (incl. constrained, dual-mobility, and head size <28 mm). Lastly, all remaining prostheses previously identified as having a higher than anticipated rate of revision (HTARR) were also excluded.

RESULTS

These exclusions progressively reduced the cumulative percent revision (CPR) rate. The final comparator, which only includes satisfactory-performed prostheses of contemporary design and use, has a 10-year CPR of 4.30% (95% CI, 4.2-4.41) which is lower than 4.93% (95% CI, 4.84-5.02) for the current comparator used by the AOANJRR (all prostheses excluding LHMOM). Over the study period, 13 additional components were identified utilising the modified comparator.

CONCLUSIONS

The calculation of the comparator revision rate should be re-evaluated to include only modern prosthesis constructs to ensure that poorly performing prostheses are identified early.

Debulking of the Femoral Stem in a Primary Total Hip Joint Replacement: A Novel Method to Reduce Stress Shielding

In current-generation designs of total primary hip joint replacement, the prostheses are fabricated from alloys. The modulus of elasticity of the alloy is substantially higher than that of the surrounding bone. This discrepancy plays a role in a phenomenon known as stress shielding, in which the bone bears a reduced proportion of the applied load. Stress shielding has been implicated in aseptic loosening of the implant which, in turn, results in reduction in the in vivo life of the implant. Rigid implants shield surrounding bone from mechanical loading, and the reduction in skeletal stress necessary to maintain bone mass and density results in accelerated bone loss, the forerunner to implant loosening. Femoral stems of various geometries and surface modifications, materials and material distributions, and porous structures have been investigated to achieve mechanical properties of stems closer to those of bone to mitigate stress shielding. For improved load transfer from implant to femur, the proposed study investigated a strategic debulking effort to impart controlled flexibility while retaining sufficient strength and endurance properties. Using an iterative design process, debulked configurations based on an internal skeletal truss framework were evaluated using finite element analysis. The implant models analyzed were solid; hollow, with a proximal hollowed stem; FB-2A, with thin, curved trusses extending from the central spine; and FB-3B and FB-3C, with thick, flat trusses extending from the central spine in a balanced-truss and a hemi-truss configuration, respectively. As outlined in the International Organization for Standardization (ISO) 7206 standards, implants were offset in natural femur for evaluation of load distribution or potted in testing cylinders for fatigue testing. The commonality across all debulked designs was the minimization of proximal stress shielding compared to conventional solid implants. Stem topography can influence performance, and the truss implants with or without the calcar collar were evaluated. Load sharing was equally effective irrespective of the collar; however, the collar was critical to reducing the stresses in the implant. Whether bonded directly to bone or cemented in the femur, the truss stem was effective at limiting stress shielding. However, a localized increase in maximum principal stress at the proximal lateral junction could adversely affect cement integrity. The controlled accommodation of deformation of the implant wall contributes to the load sharing capability of the truss implant, and for a superior biomechanical performance, the collared stem should be implanted in interference fit. Considering the results of all implant designs, the truss implant model FB-3C was the best model.

The efficacy of pericapsular nerve group block for reducing pain and opioid consumption after total hip arthroplasty: a systematic review and meta-analysis

BACKGROUND

Pericapsular nerve group block (PENG) is an emerging regional anesthesia technique for hip surgery. However, its efficacy in total hip arthroplasty (THA) isn't well defined. We perform this meta-analysis aiming to assess the effect of Pericapsular nerve group block on pain control and morphine consumption in patients with total hip arthroplasty.

METHODS

We searched four electronic databases (Pubmed, Embase, Cochrane Library, and Web of Science dated from 2018 to October 2023) for published eligible randomized controlled trials (RCTs) comparing PENG with placebo (no block/sham block) after THA. The outcome measurements consisted of pain score, opioid consumption, Time to first opioid, and postoperative complications. All data analyses were performed using STATA 12.0.

RESULTS

Five RCTs comprising 808 participants were included. Our meta-analysis showed that there were significant differences between two groups in terms of pain score in PACU (WMD =  - 0.598, 95% CI [- 0.886, - 0.310], P < 0.001), pain score at 6 h (WMD =  - 0.614, 95% CI [- 0.835, - 0.392], P < 0.001) and time to first opioid (WMD = 5.214, 95% CI [4.545, 5.883], P < 0.001). However, no significant differences were revealed from the pain score at 24 h after THA (WMD =  - 0.924, 95% CI [- 1.929, 0.081], P = 0.072). Meanwhile, the meta-analysis indicated that PENG significantly reduced 24-h opioid consumption (WMD =  - 6.168, 95% CI [- 6.667, - 5.668], P < 0.001) and 48-h opioid consumption (WMD =  - 7.171, 95% CI [- 8.994, - 5.348], P < 0.001).

CONCLUSION

Pericapsular nerve group block was effective for pain control up to postoperative 6 h and extending the time to the first opioid after THA. Moreover, it reduced postoperative opioid consumption when compared with a placebo group. Due to the high heterogeneity of the pain score after 24 h and the low-quality evidence, more high-quality RCTs are required to draw a definitive conclusion about pain control.

Intra-articular injection of miRNA-1 agomir, a novel chemically modified miRNA agonists alleviates osteoarthritis (OA) progression by downregulating Indian hedgehog in rats

Our objective in this study is to determine whether intra-articular injection of miRNA-1 can attenuate the progression of OA in rats by down regulating Ihh. Knee chondrocytes were isolated from male Sprague-Dawley rats aged 2-3 days. Second-generation chondrocytes were transfected with miR-1 mimic and empty vector with lipo3000 for 6 h and then stimulated with 10 ng/mL IL-1β for 24 h. OA-related and cartilage matrix genes were quantified using real-time quantitative polymerase chain reaction (RT-qPCR). Two-month-old male Sprague-Dawley rats were divided into three groups (n = 30?): sham operation group + 50 µL saline, anterior cruciate ligament transection (ACLT) group + 50 µL miR-1 agomir (concentration), and control group ACLT + 50 µL miR-1 agomir. Treatment was started one week after the operation. All animals were euthanized eight weeks after the operation. X-rays and micro-CT were used to detect imaging changes in the knee joints. FMT was used to monitor joint inflammation in vivo. Safranin O staining was used to detect morphological changes in articular cartilage. Immunohistochemistry was used to detect Col2, Col10, metalloproteinase-13 (MMP-13). RT-qPCR was used to detect gene changes includingmiR-1, Col2, Col10, MMP-13, Ihh, Smo, Gli1, Gli2, and Gli3. Overexpression of miR-1 in IL-1β-stimulated chondrocytes reduced the levels of Ihh, MMP-13, and Col10 but increased the levels of Col2 and aggrecan. Intra-articular injection of miR-1 agomir reduced osteophyte formation, inflammation, and prevented cartilage damage. RT-qPCR results indicated that the miR-1 agomir increased articular cartilage anabolism and inhibited cartilage catabonism. miR-1 can attenuate the progression of OA by downregulating Ihh.

Material-Intrinsic NIR-Fluorescence Enables Image-Guided Surgery for Ceramic Fracture Removal

Hip arthroplasty effectively treats advanced osteoarthritis and is therefore entitled as "operation of the 20th century." With demographic shifts, the USA alone is projected to perform up to 850 000 arthroplasties annually by 2030. Many implants now feature a ceramic head, valued for strength and wear resistance. Nonetheless, a fraction, up to 0.03% may fracture during their lifespan, demanding complex removal procedures. To address this, a radiation-free, fluorescence-based image-guided surgical technique is presented. The method uses the inherent fluorescence of ceramic implant materials, demonstrated through chemical and optical analysis of prevalent implant types. Specifically, Biolox delta implants exhibited strong fluorescence around 700 nm with a 74% photoluminescence quantum yield. Emission tails are identified extending into the near-infrared (NIR-I) biological transparency range, forming a vital prerequisite for the label-free visualization of fragments. This ruby-like fluorescence could be attributed to Cr within the zirconia-toughened alumina matrix, enabling the detection of even deep-seated millimeter-sized fragments via camera-assisted techniques. Additionally, fluorescence microscopy allowed detection of µm-sized ceramic particles, enabling debris visualization in synovial fluid as well as histological samples. This label-free optical imaging approach employs readily accessible equipment and can seamlessly transition to clinical settings without significant regulatory barriers, thereby enhancing the safety, efficiency, and minimally invasive nature of fractured ceramic implant removal procedures.

Evaluation of an early-stage prototype polyurethane femoral head implant for hip arthroplasty

Introduction

Thi study evalautes a new bone-preserving femoral head cover that mimics the articular cartilage of the femoral head.

Methods

A specially developed polyurethane (PU) was evaluated in biocompatibility (cytotoxicity test) and mechanical response to tensile loading. In the cytotoxicity test, steam sterilized (SS) and ethylene oxide sterilized (EtO) PU samples were incubated separately in a cell culture medium. The seeded cell line MG-63 was then added to these sample-incubated cell culture mediums. One negative control group and one positive control group were also evaluated. The cells in each group were cultured for seven days before being quantified using the alamarBlue assay. In the mechanical test, the femoral head cover implants were separated into three groups of three samples. Each group represented a different implant insertion idea: direct insertion (uc sample) and another two insertion modes (is and ss samples) representing implants with enclosure mechanisms. The test consisted of distance-controlled cyclic tensile loadings followed by a failure test.

Results

The cytotoxicity test results show no significant difference in fluorescence intensity between the negative control, the three SS groups, and one EtO group (P > 0.05). However, the other two EtO groups exhibit significantly lower fluorescence intensity compared with the negative control (P < 0.05). In the mechanical test, the is samples have the highest cyclic loading force at 559.50 ± 51.41 N, while the uc samples exhibit the highest force in the failure test at 632.16 ± 50.55 N. There are no significant differences (P > 0.05) among the uc, is, and ss groups in terms of stiffness.

Conclusion

The cytotoxicity test and the mechanical experiment provide initial assessments of the proposed PU femoral head cover implant. The evaluation outcomes of this study could serve as a foundation for developing more functional design and testing methods, utilizing numerical simulations, and developing animal/clinical trials in the future.

TiO2 nanotube topography enhances osteogenesis through filamentous actin and XB130-protein-mediated mechanotransduction

TiO2 nanotube topography, as nanomechanical stimulation, can significantly promote osteogenesis and improve the osteointegration on the interface of implants and bone tissue. However, the underlying mechanism has not been fully elucidated. XB130 is a member of the actin filament-associated protein family and is involved in the regulation of cytoskeleton and tyrosine kinase-mediated signalling as an adaptor protein. Whether XB130 is involved in TiO2 nanotubes-induced osteogenic differentiation and how it functions in mechano-biochemical signalling transduction remain to be elucidated. In this study, the role of XB130 on TiO2 nanotube-induced osteogenesis and mechanotransduction was systematically investigated. TiO2 nanotube topography was fabricated via anodic oxidation and characterized. The osteogenic effect was significantly accelerated by the TiO2 nanotube surface in vitro and vivo. XB130 was significantly upregulated during this process. Moreover, XB130 overexpression significantly promoted osteogenic differentiation, whereas its knockdown inhibited it. Filamentous actin depolymerization could change the expression and distribution of XB130, thus affecting osteogenic differentiation. Mechanistically, XB130 could interact with Src and result in the activation of the downstream PI3K/Akt/GSK-3β/β-catenin pathway, which accounts for the regulation of osteogenesis. This study for the first time showed that the enhanced osteogenic effect of TiO2 nanotubes could be partly due to the filamentous actin and XB130 mediated mechano-biochemical signalling transduction, which might provide a reference for guiding the design and modification of prostheses to promote bone regeneration and osseointegration. STATEMENT OF SIGNIFICANCE: TiO2 nanotubes topography can regulate cytoskeletal rearrangement and thus promote osteogenic differentiation of BMSCs. However, how filamentous actin converts mechanical stimulus into biochemical activity remains unclear. XB130 is a member of actin filament-associated protein family and involves in the regulation of tyrosine kinase-mediated signalling. Therefore, we hypothesised that XB130 might bridge the mechano-biochemical signalling transduction during TiO2 nanotubes-induced osteogenic differentiation. For the first time, this study shows that TiO2 nanotubes enhance osteogenesis through filamentous actin and XB130 mediated mechanotransduction, which provides new theoretical basis for guiding the design and modification of prostheses to promote bone regeneration and osseointegration.

The weight of complications: high and low BMI have disparate modes of failure in total hip arthroplasty

BACKGROUND

Body mass index (BMI) has been shown to influence risk for revision total hip arthroplasty (rTHA), but few studies have specifically examined which causes of rTHA are most likely in different BMI classes. We hypothesized that patients in different BMI classes would undergo rTHA for disparate reasons.

METHODS

Ninety-eight thousand six hundred seventy patients undergoing rTHA over 2006-2020 were identified in the National Inpatient Sample. Patients were classified as underweight, normal-weight, overweight/obese, or morbidly obese. Multivariable logistic regression was used to analyze the impact of BMI on rTHA for periprosthetic joint infection (PJI), dislocation, periprosthetic fracture (PPF), aseptic loosening, or mechanical complications. Analyses were adjusted for age, sex, race/ethnicity, socioeconomic status, insurance, geographic region, and comorbidities.

RESULTS

Compared to normal-weight patients, underweight patients were 131% more likely to have a revision due to dislocation and 63% more likely due to PPF. Overweight/obese patients were 19% less likely to have a revision due to dislocation and 10% more likely due to PJI. Cause for revision in morbidly obese patients was 4s1% less likely to be due to dislocation, 8% less likely due to mechanical complications, and 90% more likely due to PJI.

CONCLUSIONS

Overweight/obese and morbidly obese patients were more likely to undergo rTHA for PJI and less likely for mechanical reasons compared to normal weight patients. Underweight patients were more likely to undergo rTHA for dislocation or PPF. Understanding the differences in cause for rTHA among the BMI classes can aid in patient-specific optimization and management to reduce postoperative complications.

LEVEL OF EVIDENCE

III.

Outcomes of Dual Mobility Bearings in Revision Total Hip Replacements

Background Dual mobility bearings have gained attention in the prevention of instability in revision total hip replacement. This study aimed to evaluate the use of dual mobility bearings in revision total hip replacement. The primary outcome was the rate of dislocation. Secondary outcomes included the rate of re-operation for any reason, surgical complications, serious medical adverse events, and 90-day mortality rate. Methods A single-centre case series of 55 consecutive operations in 49 patients who underwent revision total hip replacement using dual mobility bearings with a minimum follow-up of three months was studied.  Results Early dislocation occurred in one case (2%), and there were no intra-prosthetic dislocations at a mean follow-up of 16 months. The rate of re-operation for any reason was 6/55 (11%) cases, and the post-operative infection rate was 2/55 (4%) cases. Serious medical adverse events occurred in 2/55 (4%) cases. The 90-day mortality rate was 1/55 (2%) cases. Two cases (2%) had cup abduction or anteversion angles outside of the safe zones although there were no dislocations in these patients. Conclusion This case series demonstrates a low dislocation rate in the early post-operative period for dual mobility bearings in revision total hip replacement. Dual mobility bearings show promise as an early low dislocation implant in revision total hip replacement. It remains to be determined whether dual mobility bearings are low-wear implants in the long term.

Predictors of physical activity recovery after total hip arthroplasty: a prospective observational study

PURPOSE

Little is known about the changes and the factors in physical activity as following total hip arthroplasty (THA). There are potential discrepancies between subjective and objective measurements of physical activity. Thus, our porpose is to compare objective and subjective measurements of activity levels in patients undergoing THA preoperatively, three months and one year following surgery, and investigated the factors that predicts the objective activity level after THA.

METHODS

This prospective observational study included 42 patients with unilateral symptomatic hip osteoarthritis who underwent THA. The objective activity level (step counts, sit-to-stands, and upright time) by using a tri-axial accelerometer, PRO (Oxford hip score; OHS and University of California, Los Angeles activity score; UCLA score), and muscle volume around the hip joint by using preoperative computed tomography were measured.

RESULTS

The number of steps, OHS, and UCLA score before, at three months, and one year after THA averaged 5092, 6532, and 6545 steps, 30.3, 43.0, and 44.2 points, and 3.4, 4.8, and 4.6 points, respectively, with significant postoperative increases (P < 0.05). No significant difference was found between three months and one year postoperatively. In multivariate analysis, younger age and higher preoperative contralateral gluteal medius volume were the predictors of higher postoperative step counts (P < 0.05).

CONCLUSIONS

Physical activity, including step counts, OHS, and UCLA score increased significantly until three months after unilateral THA. Early surgical intervention before contralateral muscle declines and preoperative rehabilitation including contralateral side may additionally improve postoperative activity levels.