Comparative Epidemiology of Revision Arthroplasty: Failed THA Poses Greater Clinical and Economic Burdens Than Failed TKA

The Use of General Anesthesia in Revision Joint Arthroplasty

BACKGROUND

Several studies have suggested that spinal anesthesia gives superior outcomes for primary total joint arthroplasty (TJA). However, there is a lack of available data regarding contemporary general anesthesia (GA) approaches for revision TJA utilized at high-volume joint arthroplasty centers.

METHODS

We retrospectively reviewed a series of 850 consecutive revision TJAs (405 revision total hip arthroplasties [rTHAs] and 445 revision total knee arthroplasties [rTKAs]) performed over four years at a single institution that uses a contemporary GA protocol and reported on the lengths of stay, early recovery rates, perioperative complications, and readmissions.

RESULTS

Of the revision arthroplasty patients, 74.4% (632 of 850) were discharged on postoperative day one and 68.5% (582 of 850) of subjects were able to participate in physical therapy on the day of surgery. Only six patients (0.7%) required an intensive care unit stay postoperatively. The 90-day readmission rate over this time was 11.3% (n = 96), while the reoperation rate was 9.4% (n = 80).

CONCLUSION

While neuraxial anesthesia is commonly preferred when performing revision TJA, we have demonstrated favorable safety and efficiency metrics utilizing GA in conjunction with contemporary enhanced recovery pathways. Our data supports the notion that modern GA techniques can be successfully used in revision total joint arthroplasty.

Infection Rates After Aseptic Revision Total Hip Arthroplasty With Extended Oral Antibiotic Prophylaxis

INTRODUCTION

Few US studies have investigated the efficacy of extended oral antibiotic prophylaxis (EOAP) in the prevention of periprosthetic joint infection (PJI) after aseptic revision total hip arthroplasty (R-THA). This study compared PJI rates in aseptic R-THA performed with EOAP with PJI rates in published studies of aseptic R-THA patients not receiving EOAP.

METHODS

Prospectively documented data on 127 consecutive aseptic R-THAs were retrospectively reviewed. Evidence-based perioperative infection prevention protocols were used, and all patients were discharged on 7-day EOAP. Superficial and deep infections at 30 and 90 days postoperatively and at mean latest follow-up of 27.8 months were statistically compared with all US studies reporting the prevalence of PJI after aseptic R-THA. Complications related to EOAP within 120 days of the index procedure also are reported.

RESULTS

No superficial or deep infections were observed at 30 and 90 days postoperatively when 7-day postdischarge EOAP was used. Superficial and deep infection rates were 1.57% (two patients) and 3.15% (four patients) at mean latest follow-up, respectively. Comparisons with published 30-day PJI rates of 1.37% ( P = 0.423) and 1.85% ( P = 0.257) were not statistically significant. Two of four comparisons with published 90-day PJI rates of 3.43% ( P = 0.027) and 5.74% ( P = 0.001) were statistically different. The deep PJI rate of 3.15% at mean latest follow-up was significantly lower than two of three published rates at equivalent follow-up including 10.10% ( P = 0.009) and 9.12% ( P = 0.041). No antibiotic-related complications were observed within 120 days of the index procedure.

DISCUSSION

Study findings possibly support the use of EOAP after aseptic R-THA to prevent catastrophic PJI with revision implants, indicating that the efficacy of EOAP cannot be definitively ruled-in or ruled-out based on available evidence.

Identification of Surgeon Outliers to Improve Cost Efficiency: A Novel Use of the Centers for Medicare and Medicaid Quality Payment Program

BACKGROUND

Bundled payment programs for total joint arthroplasty (TJA) have become popular among both private and public payers. Because these programs provide surgeons with financial incentives to decrease costs through reconciliation payments, there is an advantage to identifying and emulating cost-efficient surgeons. The objective of this study was to utilize the Centers for Medicare and Medicaid Services (CMS) Quality Payment Program (QPP) in combination with institutional data to identify cost-efficient surgeons within our region and, subsequently, identify cost-saving practice patterns.

METHODS

Data was obtained from the CMS QPP for total knee arthroplasty (TKA) and total hip arthroplasty (THA) surgeons within a large metropolitan area from January 2019 to December 2021. A simple linear regression determined the relationship between surgical volume and cost-efficiency. Internal practice financial data determined whether patients of identified surgeons differed with respect to x-ray visits, physical therapy visits, out-of-pocket payments to the practice, and whether surgery was done in hospital or surgical center settings.

RESULTS

There were 4 TKA and 3 THA surgeons who were cost-efficiency outliers within our area. Outliers and nonoutlier surgeons had patients who had similar body mass index, American Society of Anesthesiologists Physical Status Score, and age-adjusted Charlson Comorbidity Index scores. Patients of these surgeons had fewer x-ray visits for both TKA and THA (1.06 versus 1.11, P < .001; 0.94 versus 1.15, P < .001) and lower out-of-pocket costs ($86.10 versus $135.46, P < .001; $116.10 versus $177.40, P < .001). If all surgeons performing > 30 CMS cases annually within our practice achieved similar cost-efficiency, the savings to CMS would be $17.2 million for TKA alone ($75,802,705 versus $93,028,477).

CONCLUSIONS

The CMS QPP can be used to identify surgeons who perform cost-efficient surgeries. Practice patterns that result in cost savings can be emulated to decrease the cost curve, resulting in reconciliation payments to surgeons and institutions and cost savings to CMS.

Risk equations for prosthetic joint infections (PJIs) in UK: a retrospective study using the Clinical Practice Research Datalink (CPRD) AURUM and GOLD databases

BACKGROUND

Prosthetic joint infections (PJIs) are a serious negative outcome of arthroplasty with incidence of about 1%. Risk of PJI could depend on local treatment policies and guidelines; no UK-specific risk scoring is currently available.

OBJECTIVE

To determine a risk quantification model for the development of PJI using electronic health records.

DESIGN

Records in Clinical Practice Research Datalink (CPRD) GOLD and AURUM of patients undergoing hip or knee arthroplasty between January 2007 and December 2014, with linkage to Hospital Episode Statistics and Office of National Statistics, were obtained. Cohorts' characteristics and risk equations through parametric models were developed and compared between the two databases. Pooled cohort risk equations were determined for the UK population and simplified through stepwise selection.

RESULTS

After applying the inclusion/exclusion criteria, 174 905 joints (1021 developed PJI) were identified in CPRD AURUM and 48 419 joints (228 developed PJI) in CPRD GOLD. Patients undergoing hip or knee arthroplasty in both databases exhibited different sociodemographic characteristics and medical/drug history. However, the quantification of the impact of such covariates (coefficients of parametric models fitted to the survival curves) on the risk of PJI between the two cohorts was not statistically significant. The log-normal model fitted to the pooled cohorts after stepwise selection had a C-statistic >0.7.

CONCLUSIONS

The risk prediction tool developed here could help prevent PJI through identifying modifiable risk factors pre-surgery and identifying the patients most likely to benefit from close monitoring/preventive actions. As derived from the UK population, such tool will help the National Health Service reduce the impact of PJI on its resources and patient lives.

The outcome of revision total hip arthroplasty for instability

Aims

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

Methods

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

Results

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

Conclusion

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

Early Discharge for Revision Total Knee and Hip Arthroplasty: Predictors of Success

BACKGROUND

The rate of revision total joint arthroplasties is expected to increase drastically in the near future. Given the recent pandemic, there has been a general push toward early discharge. This study aimed to assess for predictors of early postoperative discharge after revision total knee arthroplasty (rTKA) and revision total hip arthroplasty (rTHA).

METHODS

There were 77 rTKA and 129 rTHA collected between January 1, 2019 and December 31, 2021. Demographic data, comorbidities, a comorbidity index, the modified frailty index (mFI-5), and surgical history were collected. The Common Procedural Terminology codes for each case were assessed. Patients were grouped into 2 cohorts, early discharge (length of stay [LOS] <24 hours) and late discharge (LOS >24 hours).

RESULTS

In the rTHA cohort, age >65 years, a history of cardiac or liver disease, an mFI-5 of >1, a comorbidity index of >2.7, a surgical time >122 minutes, and the need for a transfusion were predictors of prolonged LOS. Only the presence of a surgical time of >63 minutes or an mFI-5 >1 increased patient LOS in the rTKA cohort. In both rTHA and rTKA patients, periprosthetic joint infection resulted in a late discharge for all patients, mean 4.8 and 7.1 days, respectively. Dual component revision was performed in 70.5% of rTHA. Only 27.6% of rTKA were 2-component revisions or placements of an antibiotic spacer.

CONCLUSIONS

Several patient and surgical factors preclude early discharge candidacy. For rTHA, an mFI-5 of >2/5, comorbidity index of >4, or a surgical time of >122 minutes is predictive of prolonged LOS. For rTKA, an mFI-5 of >2/5, Charlson Comorbidity Index of >5, or a surgical time of >63 minutes predicts prolonged LOS.

Health status after periprosthetic proximal femoral fractures

Aims

Periprosthetic proximal femoral fractures (PFFs) are a major complication after total hip arthroplasty (THA). Health status after PFF is not specifically investigated. The aim of this study is to evaluate the health status pattern over two years after sustaining a PFF.

Methods

A cohort of patients with PFF after THA was derived from the Brabant Injury Outcomes Surveillance (BIOS) study. The BIOS study, a prospective, observational, multicentre follow-up cohort study, was conducted to obtain data by questionnaires pre-injury and at one week, and one, three, six, 12, and 24 months after trauma. Primary outcome measures were the EuroQol five-dimension three-level questionnaire (EQ-5D-3L), the Health Utility Index 2 (HUI2), and the Health Utility Index 3 (HUI3). Secondary outcome measures were general measurements such as duration of hospital stay and mortality.

Results

A total of 70 patients with a PFF were included. EQ-5D utility scores were significantly lower on all timepoints except at six months' follow-up compared to pre-injury. EuroQol visual analogue scale (EQ-VAS) scores at one month's follow-up were significantly lower compared to pre-injury. The percentage of reported problems at two years was higher for all dimensions except anxiety/depression when compared to pre-injury. The mean EQ-5D utility score was 0.26 higher in males compared to females (95% confidence interval (CI) 0.01 to 0.42; p = 0.003). The mean EQ-VAS score for males was 8.9 points higher when compared to females over all timepoints (95% CI 1.2 to 16.7; p = 0.027). Mortality was 10% after two years' follow-up.

Conclusion

PFF patients are a frail population with substantial functional impairment at baseline. Post-injury, they have a significant and clinically relevant lower health status two years after trauma when compared to pre-injury. Health status improves the most between one and three months after injury. Two years after PFF, more patients experience problems in mobility, self-care, usual activities, and pain/discomfort than pre-injury.

Use of dual mobility cup cemented into a tantalum acetabular shell for hip revision with large bone loss can decrease dislocation risk without increasing the risk of mechanical failure

BACKGROUND

Porous tantalum components and augments have demonstrated short to midterm fixation stability in acetabular total hip arthroplasty (THA) revision but do not offer a novel option to decrease the postoperative dislocation rate. Recently, dual mobility (DM) cups have gained interest to decrease the prevalence of recurrent hip instability after revision hip arthroplasty, but this issue was not confirmed combined with use of tantalum reconstruction devices. Therefore, we did a retrospective study aiming to: (1) evaluate at a 5-year minimum follow-up period the dislocation rate (and other intra- and postoperative complications), (2) assess radiographic results specifically looking at osseointegration and restoration of the hip center, (3) and also clinical results in a cohort of patients who underwent complex acetabular reconstruction with trabecular metal revision components associated with a cemented DM socket.

HYPOTHESIS

Using a DM socket cemented in porous tantalum components can reach the low risk of hip dislocation reported with DM components in revision setting without increasing the risk of a mechanical failure.

METHODS

A cross-sectional study identified 174 THA revision including an acetabular revision. Were excluded 118 revisions with acetabular defects Type 1, 2a or 2B according to Paprosky's classification, as well as 18 hips revised without a dual mobility and 3 patients (3 hips) lost to follow-up. Were thus included in this study 35 hips (35 patients) implanted with uncemented total hip arthroplasty revision using both trabecular metal acetabular cup-cage reconstruction and a cemented DM cup. Seven hips were classified Paprosky types 2C, 15 type 3A and 13 types 3B. Patients were followed with clinical and radiological evaluation regarding dislocation rate, infection, reoperation or re-revision, osseointegration and restoration of the hip center, and functional results according to the Harris hip score and psoas impingement presence.

RESULTS

At a mean follow-up of 8.1±1.8 years (5.1-12.6), one dislocation was recorded, and one acute deep infection. No patient required a cup re-revision for septic or aseptic loosening. The survivorship at 8years regarding revision for any cause as an endpoint was 96.5% (CI95%: 92-99). Osseointegration of TM implants was analyzed and found no acetabular migration at the last follow-up in the cohort. The mean hip center position was optimized from 48±7mm (37-58) to 34±5mm (29-39) vertically and from 26±5mm (-18-36) to 24±8mm (7-31) horizontally without reaching significance (p=0.1). On the last follow-up X-rays, the mean acetabular inclination was 47̊±9̊ (32̊-61̊). According to the criteria of Hirakawa, 97.1% (34/35) of the hip centers were restored. One cup (2.9%) was more than 5mm proximally from the hip center, and none more than 10mm. Clinical results assessed a Harris Hip Score improved from 36±17 (23-62) preoperatively to 82±15 (69-93) at last follow-up (p<0.0001). Two patients (2/35, 5.7%) complained of psoas impingement.

CONCLUSION

This study suggests effectiveness of DM cups in association with a tantalum-made acetabular shell for reconstruction of large bone defect in THRs for both solving postoperative instability and aseptic loosening without increasing the re-revision rate for any reason in a midterm follow-up.

LEVEL OF EVIDENCE

IV; observational study.

Comparing outcomes in revision total hip arthroplasty in inpatient versus outpatient setting: a matched cohort analysis

BACKGROUND

As the population ages, revision total hip arthroplasty (rTHA) is becoming more common. However, there is a paucity of literature regarding perioperative outcomes following inpatient versus outpatient rTHA. Our study aims to compare perioperative complications and readmission rates associated with rTHA in a large national cohort.

METHODS

A retrospective, propensity-matched cohort study was conducted using the National Surgical Quality Improvement Program database from 2006 to 2020. Patients undergoing rTHA in the inpatient setting were propensity matched to patients receiving rTHA in the outpatient setting. Following 1:1 matching, multivariate analyses were performed to compare perioperative complications and readmission.

RESULTS

A total of 207,102 patients were identified, including 181,164 outpatient primary THA, 25,466 inpatient rTHA, and 492 outpatient rTHA patients. Following propensity matching, outpatient primary THA versus outpatient rTHA had 210 patients and inpatient rTHA versus outpatient rTHA had 214 patients. Patients in the outpatient rTHA had a significantly higher operative time (132.4 ± 73.2 versus 90.9 ± 32.7, p < 0.001) and length of stay (1.6 ± 1.6 vs. 0.9 ± 1.0, p < 0.001) compared to outpatient primary THA. When comparing inpatient versus outpatient rTHA, the outpatient cohort had lower operative time (131.1 ± 70.9 vs. 145.4 ± 71.5, p = 0.038), total length of stay (1.7 ± 1.8 vs. 3.6 ± 4.1, p < 0.001), and bleeding complications (6% vs. 18%, p < 0.001).

CONCLUSION

There were no difference in the odds of complications between outpatient primary and revision THA. Additionally, rTHA performed in an outpatient setting did not show any increase in immediate compared to inpatient settings. These findings suggest that rTHA can be safely performed on certain patients.

Cemented dual-mobility constructs in uncemented revision acetabular components

Aims

Dislocation remains a leading cause of failure following revision total hip arthroplasty (THA). While dual-mobility (DM) bearings have been shown to mitigate this risk, options are limited when retaining or implanting an uncemented shell without modular DM options. In these circumstances, a monoblock DM cup, designed for cementing, can be cemented into an uncemented acetabular shell. The goal of this study was to describe the implant survival, complications, and radiological outcomes of this construct.

Methods

We identified 64 patients (65 hips) who had a single-design cemented DM cup cemented into an uncemented acetabular shell during revision THA between 2018 and 2020 at our institution. Cups were cemented into either uncemented cups designed for liner cementing (n = 48; 74%) or retained (n = 17; 26%) acetabular components. Median outer head diameter was 42 mm. Mean age was 69 years (SD 11), mean BMI was 32 kg/m2 (SD 8), and 52% (n = 34) were female. Survival was assessed using Kaplan-Meier methods. Mean follow-up was two years (SD 0.97).

Results

There were nine cemented DM cup revisions: three for periprosthetic joint infection, three for acetabular aseptic loosening from bone, two for dislocation, and one for a broken cup-cage construct. The two-year survivals free of aseptic DM revision and dislocation were both 92%. There were five postoperative dislocations, all in patients with prior dislocation or abductor deficiency. On radiological review, the DM cup remained well-fixed at the cemented interface in all but one case.

Conclusion

While dislocation was not eliminated in this series of complex revision THAs, this technique allowed for maximization of femoral head diameter and optimization of effective acetabular component position during cementing. Of note, there was only one failure at the cemented interface.

Functional Acetabular Component Positioning During Direct Anterior Approach Hip Arthroplasty Using a Novel Three-Dimensional Virtual Mesh Imaging System With Fluoroscopy

BACKGROUND

Optimal position of total hip arthroplasty (THA) components is critical for joint mechanics and stability. Acetabular component positioning during supine surgery in direct anterior approach (DAA) THA may be different in the standing position postoperatively, which traditional fluoroscopy is unable to predict. A novel 3-dimensional (3D) image analysis technology (IAT) that uses artificial intelligence to measure the tilt and rotation of the pelvis has enabled prediction of component positioning from supine to standing. The purpose of this study was to compare intraoperative fluoroscopy, non-3D-IAT, and 3D-IAT with postoperative standing radiographs to assess the accuracy of component positioning.

METHODS

From 2022 to 2023, 30 consecutive patients (86.6% women, mean age 59 [range, 55 to 67]) undergoing primary DAA THA with the use of the 3D-IAT were identified. A separate cohort of 148 patients from 2020 to 2021 (85% women, mean age 65 [range, 55 to 69]) who underwent DAA THA with non-3D-IAT was used for comparison. Leg length discrepancy (LLD), cup anteversion, and inclination were manually measured on intraoperative fluoroscopic images and digitally measured using IAT. Follow-up evaluation occurred at 1 month with standing pelvis radiographs measured using Ein Bild Röntgen Analyze-Cup software. Measurements were compared via Wilcoxon signed rank tests where P ≤ .05 indicates significantly different measurements.

RESULTS

Median LLD, inclination, and anteversion measurements via non-3D-IAT and fluoroscopy were significantly different compared to postoperative standing radiographs (P < .001). The 3D-IAT more accurately predicted LLD, abduction, and anteversion, with values not significantly different from postoperative standing measurements (P = .23, P = .93, and P = .36, respectively).

CONCLUSIONS

The use of the 3D-IAT during DAA THA allowed for the more accurate prediction of acetabular component position in the standing position postoperatively.

Obesity and Primary Total Hip Arthroplasty: The Absolute versus Relative Risk of Periprosthetic Joint Infection at 15 Years

BACKGROUND

To make an informed decision about total hip arthroplasty (THA), surgeons and patients need to understand the absolute and relative risks of periprosthetic joint infection (PJI). We sought to evaluate the long-term risk of PJI following primary THA stratified by body mass index (BMI) and PJI-related risk factors.

METHODS

We identified 21,550 primary THAs performed from 2000 to 2021 at a single institution. Patients were stratified as having 0, 1, or ≥ 2 PJI risk factors (diabetes, chronic kidney disease, nonprimary osteoarthritis, immunosuppression, or active smoking) and into BMI categories. The 15-year cumulative risk of PJI was evaluated by BMI and PJI risk factors.

RESULTS

For the entire cohort, the 15-year absolute risk of PJI was 2%. For patients who did not have PJI risk factors, the absolute risk of PJI at 15 years was 1% in normal weight, 2% in class III obesity, and 4% in class IV obesity. Patients who had class III and IV obesity had a 3-times and 9-times higher relative risk of PJI, respectively (P = .03, P < .001). Among patients who had ≥ 2 PJI risk factors, the absolute risk of PJI at 15 years was 2% in normal weight, 4% in class III obesity, and 18% in class IV obesity.

CONCLUSIONS

Healthy patients who had class III and IV obesity had a 3-times and 9-times increased risk of PJI at 15 years relative to normal weight patients. However, the absolute risk of PJI at 15 years was 2 and 4%, respectively. Given emerging data questioning whether BMI modification decreases PJI risk, surgeons and patients must consider both a 3-times to 9-times increased relative risk of PJI and a 2 to 4% absolute risk of PJI at 15 years for healthy patients who had a BMI ≥ 40.

LEVEL OF EVIDENCE

IV.

The CCJR® Charles A. Engh, Sr, MD. Excellence in Hip Research Award: The Evolution of Revision Hip Arthroplasty and Impact on the Trainee's Experience

BACKGROUND

Advances in total hip arthroplasty (THA) have resulted in evolving revision indications and intraoperative techniques, which can influence the exposure of trainees to complex cases. We report 3 decades of revision experience from a tertiary referral center that trains fellows, comparing the reasons for revision and the complexity of revisions over time.

METHODS

We retrospectively reviewed all revision THAs performed at our institution from 1990 to 2022. Revision diagnoses, components revised, types of revision implants used, and exposure techniques were collected. A "complex" revision was defined as a case that involved an extended trochanteric osteotomy, triflange and cup-cage construct, or acetabular augment.

RESULTS

A total of 3,556 THA revisions were identified (108 revisions/year). Aseptic loosening was the most common indication in 1990 to 1999 (45 per year), but decreased to 28.3/year in 2010 to 2019. From 1990 to 1999 and 2010 to 2019, fracture increased from 3.1 to 7.3 per year, infection from 2.9/year to 16.9/year, and metallosis from 0.1 to 13.2 per year. Both component revision were common from 1990 to 1994 (42.6 per year), while polyethylene exchange was most common in 2010 to 2019 (43.3 per year). A decrease was observed in "complex" cases over time: 14.8 extended trochanteric osteotomies/year in 2000 to 2004 compared to 5.4 per year in 2018 to 2022, 4.5 triflange and cup-cage constructs/year in 2004 to 2007 compared to 0.8 per year in 2018 to 2022, and 4 acetabular augments per year in 2009 to 2012 compared to 1 per year in 2018 to 2022.

CONCLUSIONS

Indications for revision have changed over the decades, while the number of "complex" revisions has gradually decreased, presumably due to advances in implants and materials. If this trend extends to other training institutions, the next generation of arthroplasty surgeons will have less exposure to complex revisions during their training.

Large Femoral Heads With Small Acetabular Components: An Examination of 10-Year Polyethylene Wear

Highly cross-linked polyethylene (HXLPE) has improved polyethylene (PE) wear rates while decreasing osteolysis and aseptic loosening. However, concerns exist regarding the risk of mechanical failure with thin HXLPE liners in total hip arthroplasty (THA). Our purpose was to evaluate long-term outcomes and PE wear rates in primary THAs pairing large femoral heads with small acetabular components and thin HXLPE liners. We retrospectively reviewed 29 patients who underwent 33 primary THAs using large femoral heads (32 or 36 mm) with small acetabular components (48 or 50 mm) and thin HXLPE liners (3.9 or 5.9 mm) at minimum 10-year follow-up. PE liner wear was measured using a validated radiographic technique. Mean age was 66 years, 97% of the patients were women, and mean body mass index was 26.3 kg/m2. Thirty hips (90.9%) had ceramic femoral heads, and 13 hips (39%) had 36-mm femoral heads with 3.9-mm HXLPE liners. All cases used a neutral PE design. Mean linear wear rate and volumetric wear rate were 0.04 mm/year and 39.6 mm3/year, respectively, at mean 10.9-year follow-up. There were no instances of liner fracture, liner dissociation, or revision. Mean Hip disability and Osteoarthritis Outcome Score for Joint Replacement (HOOS, JR) was 92.1. In the largest long-term study of primary THAs using large femoral heads with small acetabular components and thin HXLPE liners, we found low linear and volumetric wear rates and no cases of liner mechanical failures. Thin HXLPE liners are a safe and viable option for THA surgeons. [Orthopedics. 2024;47(2):118-122.].

Immediate weightbearing is safe after revision total hip arthroplasty for Vancouver B2/B3 periprosthetic femur fractures

INTRODUCTION

Modular fluted, tapered stems provide a reliable treatment for Vancouver B2/B3 fractures. Historically, these patients had weightbearing restrictions postoperatively. Although full immediate postoperative weightbearing may provide benefits in this patient population, stem subsidence is a concern.

QUESTIONS/PURPOSES

The objective of this study was to investigate the effect of post-operative weight-bearing status on stem subsidence in patients treated with modular tapered stems for Vancouver B2 and B3 periprosthetic fractures. We sought to answer two questions: (1) Does full immediate postoperative weightbearing after revision total hip arthroplasty for periprosthetic femur fracture lead to increased stem subsidence compared to protected weightbearing? (2) Is there a mortality difference between these two groups of patients with different weightbearing restrictions?

METHODS

From 2009 to 2015 all patients who underwent revision for Vancouver B2/B3 fractures were made non-weightbearing (NWB) for six weeks postoperatively. After 2015, immediate weightbearing as tolerated (WBAT) was allowed postoperatively. We compared stem subsidence between immediate postoperative and final radiographs. Additionally, we performed a Kaplan-Meijer analysis with one-year mortality as an endpoint.

RESULTS

The final cohort included forty-seven patients with an average follow-up of 254 days. The average stem subsidence was 1.0 mm (95 % CI, 0.5-1.5 mm) in the NWB cohort and 0.3 mm (95 % CI, 0-0.7 mm) in the WBAT cohort (P = 0.10). In our survivorship analysis, we noted no deaths in the WBAT cohort compared to 17 % mortality in the NWB cohort at the one-year timepoint.

CONCLUSION

Allowing patients to weight bear immediately after revision does not increase stem subsidence. Further studies are needed to determine whether early weightbearing provides a mortality benefit.

Latent infections in conversion total hip arthroplasty following internal fixation of femoral neck fractures: a systematic review and meta-analysis of diagnostic methods

BACKGROUND

Accurate diagnosis of latent infections prior to conversion total hip arthroplasty (THA) following internal fixation of femoral neck fractures is crucial for successful surgical outcomes. This systematic review aimed to provide a comprehensive evaluation of the current literature regarding the diagnosis of latent infections before conversion THA.

METHODS

Systematic search of PubMed, EMBASE, and Cochrane (CENTRAL) databases was conducted, and the diagnostic accuracy of various markers and techniques was assessed. The quality of the included studies was evaluated using the QUADAS-2 instrument.

RESULTS

Five studies comprising 661 patients were included in the review. Pooled analysis using C-reactive protein (CRP) as a diagnostic marker resulted in a sensitivity and specificity of 72% and 76%, respectively, while using erythrocyte sedimentation rate (ESR) yielded a sensitivity and specificity of 75% and 78%, respectively. Fibrinogen and platelet count showed lower sensitivity and specificity compared to CRP and ESR. The best combined markers were CRP and serum platelet count, with a sensitivity of 76% and specificity of 86% based on one study.

CONCLUSION

Our review underscored the limitations and inconsistencies present in current diagnostic methods for latent infections in conversion surgery. Future research needs to focus on standardizing threshold values, exploring the potential of synovial fluid analysis, imaging techniques, and molecular methods, as well as developing tailored diagnostic algorithms.

PROSPERO

CRD42023394757.

Debridement, antibiotics, and implant retention (DAIR) for the early prosthetic joint infection of total knee and hip arthroplasties: a systematic review

PURPOSE

Early periprosthetic joint infection (PJI) represents one of the most fearsome complications of joint replacement. No international consensus has been reached regarding the best approach for early prosthetic knee and hip infections. The aim of this updated systematic review is to assess whether debridement, antibiotics, and implant retention (DAIR) is an effective choice of treatment in early postoperative and acute hematogenous PJI.

METHODS

This systematic review was performed using the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. The diagnostic criteria defining a PJI, the most present pathogen, and the days between the index procedure and the onset of the PJI were extracted from the selected articles. Additionally, the mean follow-up, antibiotic regimen, and success rate of the treatment were also reported.

RESULTS

The articles included provided a cohort of 970 patients. Ten studies specified the joint of their cohort in PJIs regarding either hip prostheses or knee prostheses, resulting in 454 total knees and 460 total hips. The age of the patients ranged from 18 to 92 years old. Success rates for the DAIR treatments in the following cohort ranged from 55.5% up to a maximum of 90% (mean value of 71%).

CONCLUSION

Even though the DAIR procedure is quite limited, it is still considered an effective option for patients developing an early post-operative or acute hematogenous PJI. However, there is a lack of studies, in particular randomized control trials (RCTs), comparing DAIR with one-stage and two-stage revision protocols in the setting of early PJIs, reflecting the necessity to conduct further high-quality studies to face the burden of early PJI.

Prevalence of Depressive Symptoms in Aseptic Revision Total Knee Arthroplasty Based on the Mode of Failure

Background

Complications following total knee arthroplasty (TKA) that necessitate revision cause considerable psychological distress and symptoms of depression, which are linked to poorer postoperative outcomes, increased complications, and increased healthcare utilization. We aimed to identify the prevalence of mental health disorders and symptoms preoperatively and postoperatively in patients undergoing aseptic revision TKA and to stratify these patients based on their mechanism of failure.

Methods

All patients undergoing aseptic revision TKA from 2008 to 2019 with a minimum 1-year follow-up were retrospectively reviewed at a single institution. Patients (n = 394) were grouped based on 7 failure modes previously described. Patients were considered to have depressive symptoms if their Veterans RAND-12 mental component score was below 42. Preoperative and postoperative Veterans RAND-12 mental component scores at the latest follow-up were evaluated.

Results

Overall comparative prevalence of preoperative to postoperative depressive symptoms was 23.4%-18.8%. By mode of failure are as follows: arthrofibrosis (25.8%-16.7%), aseptic loosening (25.3%-18.9%), extensor mechanism disruption (25%-50%), failed unicompartmental knee arthroplasty (8.6%-14.3%), instability (25.7%-17.1%), osteolysis or polyethylene wear (23.1%-23.1%), and patellar failure (11.8%-23.5%). There was no difference in depressive symptoms among failure modes preoperatively (P = .376) or at the latest postoperative follow-up (P = .175).

Conclusions

The prevalence of depressive symptoms in revision TKA patients appears to be independent of failure mode. Surgeon awareness and screening for depressive symptoms in this patient population preoperatively with referral for potential treatment may improve early postoperative outcomes.

Medicaid Patients Travel Disproportionately Farther for Revision Total Joint Arthroplasty

BACKGROUND

Access to high-quality care for revision total joint arthroplasty (rTJA) is poorly understood but may vary based on insurance type. This study investigated distance traveled for hip and knee rTJA based on insurance type.

METHODS

A total of 317 revision hips and 431 revision knees performed between 2010 and 2020 were retrospectively reviewed. Cluster sampling was used to select primary hips and knees for comparison. Median driving distance was compared based upon procedure and insurance type.

RESULTS

Revision hip and knee patients traveled 18.2 and 11.0 miles farther for surgery compared to primary hip and knee patients (P ≤ .001). For hip rTJA, Medicaid patients traveled farther than Medicare patients followed by commercially insured patients with median distances traveled of 98.4, 67.2, and 35.6 miles, respectively (P = .016). Primary hip patients traveled the same distance regardless of insurance type (P = .397). For knee rTJA, Medicaid patients traveled twice as far as Medicare and commercially insured patients (medians of 85.0, 43.5, and 42.2 miles respectively, P ≤ .046). Primary knee patients showed a similar pattern (P = .264). Age and ASA-PS classification did not indicate greater comorbidity in Medicaid patients.

CONCLUSION

Insurance type may influence rTJA referrals, with disproportionate referral of Medicaid and Medicare patients to nonlocal care centers. In addition to patient burden, these patterns potentially present a financial burden to facilities accepting referrals. Strategies to improve equitable access to rTJA, while maintaining the highest and most economical standards of care for patients, providers, and hospitals, are encouraged.

Comparison of Outcomes in High Versus Low Activity Level Patients After Total Joint Arthroplasty

BACKGROUND

Activity level (AL) recommendations following total joint arthroplasty (TJA) remain controversial. Our purpose was to compare implant survivorship of high activity (HA) and low activity (LA) patients after primary TJA. We hypothesized that there would be no difference in implant survivorship based on AL.

METHODS

This was a retrospective 1:1 matched cohort study after primary TJA with minimum 5-year follow-up. High activity patients were designated by the University of California and Los Angeles activity-level rating scale score ≥8 and matched to LA patients based on age (±5), sex, and body mass index (±5). There were 396 HA patients (149 knees and 48 hips) who met inclusion criteria. We analyzed revision rates, adverse events, and radiographic lucencies.

RESULTS

Crepitus was the most common adverse events in both HA and LA total knee arthroplasties (TKAs). Adverse events were rare in total hip arthroplasty (THA) cohorts. For both THA and TKA patients, the HA cohort did not have increased reoperations or revisions when compared to the LA cohort. No differences were noted in overall radiographic analysis between HA (16.1%) and LA (12.1%) TKA patients (P = .318), and in THA patients, more radiographic problems were noted in LA (P = .004).

CONCLUSION

We found no difference in minimum 5-year postoperative implant survivorship based on AL. This may change AL recommendations after TKA and THA.

The causal relationship between psoriasis and artificial joint re-operation after arthroplasty: A two-sample Mendelian randomization study

BACKGROUND

Psoriasis is observationally associated with a higher risk of complications of arthroplasty; however, the causal effects of psoriasis on complications of arthroplasty are yet to be established. This study was to explore the causal effect of psoriasis on artificial joint re-operation after arthroplasty through two-sample Mendelian randomization (MR).

METHODS

In the MR analysis, psoriasis was selected as the exposure in this study while single-nucleotide polymorphisms (SNPs) from a genome-wide association study (GWAS) were selected as the instrumental variables (IVs). Summary statistics data on artificial joint re-operation was extracted from publicly available GWAS data, including 218 792 European descent individuals. MR analysis was performed using the standard inverse variance weighted method (IVW). Furthermore, MR Egger, weighted median, simple mode, weighted mode, and the MR-PRESSO (Mendelian Randomization Pleiotropy Residual Sum and Outlier) test were also done to verify the results. Finally, the sensitivity analysis was executed.

RESULTS

The IVW showed that psoriasis increases the risk of artificial joint re-operation (OR = 1.12; 95% CI = (1.01, 1.25); p = 0.036). This outcome was also verified by other methods including weighted median (OR = 1.16; 95% CI = (1.03, 1.31); p = 0.015), MR Egger (OR = 1.22; 95% CI = (1.03, 1.44); p = 0.038), and weighted mode (OR = 1.16; 95% CI = (1.03, 1.30); p = 0.025). No heterogeneity and directional pleiotropy were observed upon sensitivity analysis.

CONCLUSION

The present study showed that psoriasis has a potential causal effect on artificial joint re-operation after arthroplasty. Further studies are warranted to elucidate the underlying mechanisms of causal associations between psoriasis on re-operation.

Acetabular cup fixation with and without screws following primary total hip arthroplasty: migration evaluated by radiostereometric analysis

BACKGROUND

Early cup migration after total hip arthroplasty (THA) is correlated to late revision due to aseptic loosening. However, the use of screws for increased cup stability remains unclear and debated. The purpose of this study is to assess acetabular migration between cups fixated with and without the use of screws.

METHODS

Patients underwent primary THA using either a direct anterior (DA) or a direct lateral (DL) approach. The DA surgeon routinely supplemented cup fixation with 1 or 2 screws while the DL surgeon used no screws. At 7 follow-up visits up to 2 years post operation, patients underwent radiostereometric analysis (RSA) imaging for implant migration tracking. The primary outcome was defined as proximal cup migration measured with model-based RSA.

RESULTS

68 patients were assessed up to 2 years post operation, n = 43 received screws and n = 25 did not. The use of screws had a significant effect on cup migration (p = 0.018). From 2 weeks to 2 years post operation, the total mean migration was 0.403 ± 0.681 mm and 0.129 ± 0.272 mm (p = 0.319) for cups with and without screws, respectively. The number of screws used also had a significant impact, with cups fixated with 1 screw migrating more than cups fixated with 2 (p = 0.013, mean difference 0.712 mm).

CONCLUSIONS

Acetabular cups fixated with only 1 screw resulted in greater migration than cups with no screws or 2 screws, though the mean magnitude was well under the 1.0 mm threshold for unacceptable migration. However, 3 of the 24 patients who received only 1 screw exceeded the 1.0 mm threshold for unacceptable migration. Ultimately, the results of this study show that the use of 2 screws to supplement cup fixation can provide good implant stability that is equivalent to a secure press-fit component with no screws.Clinical trial registration: ClinicalTrials.gov (NCT03558217).

Exploring needs, barriers to, and facilitators of rehabilitation exercise following revision hip replacement - A grounded theory study

PURPOSE

Evidence on rehabilitation after revision total hip replacement (THR) is inadequate and development of rehabilitation interventions is warranted. Even so, little is known about patients' experiences with revision THR rehabilitation. This study aimed to explore patients' rehabilitation exercise experiences after revision THR.

MATERIALS AND METHODS

Using constructivist grounded theory, we conducted semi-structured qualitative interviews with twelve patients with completed or almost completed rehabilitation exercise after revision THR. Data collection and analysis were a constant comparative process conducted in three phases; initial, focused, and theoretical.

FINDINGS

From the data, we generated a substantial theory of the participant's circumstances and ability to integrate rehabilitation exercise into their everyday life after revision THR. Four categories were constructed based on patients' experiences in different contexts: hesitance, fear avoidance, self-commitment, and fidelity.

CONCLUSIONS

This study highlighted that patients' expectations, past experiences, attitudes, trusts, and circumstances interact to influence engagement and adherence to rehabilitation exercise and described four categories relating to the integration of revision THR rehabilitation exercise into their everyday life. Clinicians should be aware of and account for these categories during rehabilitation exercise. Tailored individual rehabilitation exercise interventions and clinician approaches to optimize engagement and adherence are needed among patients with revision THR.

Return to work following revision knee arthroplasty in patients under 65 years of age: A retrospective study

Background

Little is known about employment following revision total knee arthroplasty (RTKA). This study aims to describe factors associated with returning to employment in patients of working age who underwent RTKA surgery.

Methods

We performed a retrospective assessment of all patients aged ≤65 who underwent RTKA at our NHS institution between 2006 and 2020. All indications and revision procedures were included. Pre-operative demographics, indication for surgery and Oxford Knee Scores (OKS) were recorded. Postal questionnaires were sent to patients including patient reported outcome measures and a departmental questionnaire asking patients about employment status pre- and post-operatively.

Results

132 procedures were performed in 113 patients. Median follow up was 5.5 years (2.4-9.0). Mean age was 58 (5.8) and 50% (57) were men. 62 patients undergoing 74 procedures responded to postal questionnaires and were included in the study. 53% (33) were employed prior to surgery and 61% (38) returned to work at a median of 12 weeks (3-150). Of the 24 who did not return to work, 7 reported intending to return to work. Those patients who returned to work had increased pre-operative OKS (16.9 vs 13.6) and mean improvement (16.5 vs 12.4).

Conclusion

This study is limited by small numbers and its observational nature. In this population the majority of patients who wished to return to work after RTKA were able to do so. This provides some reassurance when counselling patients. Prospective studies to better understand the factors that predict return to work will be important with increasing demands from surgery.

The Change of Serum Interleukin-6 Fails to Identify Subsequent Periprosthetic Joint Infection in Patients Who Have Two-Stage Revision for Periprosthetic Joint Infection

BACKGROUND

The diagnosis of persistent infection prior to second-stage reimplantation in 2-stage exchanges for periprosthetic joint infection (PJI) can be challenging as there is no optimal diagnostic tool. This study investigates the usefulness of pre-reimplantation serum C-reactive protein (CRP) and interleukin-6 (IL-6) and its change between both stages to identify patients who have subsequent PJI.

METHODS

There were 125 patients who underwent planned 2-stage exchange for chronic knee or hip PJI from a single center retrospectively identified. Patients were included if preoperative CRP and IL-6 were available for both stages. Subsequent PJI was defined as 2 positive microbiological cultures at reimplantation or subsequent surgery or death due to PJI during follow-up.

RESULTS

Prior to reimplantation, the median serum CRP (total knee arthroplasties [TKAs]: 1.0 versus 0.5 mg/dL, P = .028; total hip arthroplasties [THAs]: 1.3 versus 0.5 mg/dL, P = .015) and median IL-6 (TKA: 8.0 versus 6.0 pg/mL, P = .052; THA: 7.0 versus 6.0 pg/mL, P = .239) were higher in patients who had subsequent PJI. The IL-6 and CRP values showed moderate sensitivity (TKA/CRP: 66.7%; THA/CRP: 58.8%; TKA/IL-6: 46.7%; THA/IL-6: 35.3%) and good specificity (TKA/CRP: 66.7%; THA/CRP: 81.0%; TKA/IL-6: 86.3%; THA/IL-6: 83.3%). The change in CRP and IL-6 between the stages did not differ between the groups, respectively.

CONCLUSIONS

Serum CRP and IL-6 show low to moderate sensitivity and good specificity in the diagnosis of subsequent PJI prior to reimplantation, which questions their usefulness as a rule-out test. Furthermore, the change in between stages does not appear to identify subsequent PJI.

The Performance of Primary Dual-Mobility Total Hip Arthroplasty in Patients Aged 55 Years and Younger: A Systematic Review

Background

Dual-mobility (DM) total hip arthroplasty (THA) combines the stabilization advantage provided by large head articulation with the low friction advantage provided by small head articulation. There is momentum for DM to be used in a wider selection of patients, with some advocating for DM to be the routine primary total hip construct. Further investigation is needed to determine whether the use of DM in younger adults is validated by aggregate data. Our objective was to review the literature for the clinical performance of DM THA in patients aged 55 years and younger.

Methods

A systematic review of the literature was performed according to the guidelines of Preferred Reporting in Systematic Reviews and Meta-Analyses. Inclusion in the review required clinical outcome reporting for DM primary THA in ambulatory patients aged 55 years or younger. The risk of bias was appraised using the Cochrane risk of bias in nonrandomized studies of interventions and the quality of the evidence was appraised using the Grading of Recommendations Assessment, Development and Evaluation framework.

Results

Across a sample of 1048 cases, the frequency weighted term of follow-up was 87.7 months. The pooled rate of revision was 9.5%. The Harris Hip Score significantly improved from 49.1 preoperatively to 93 postoperatively. The Postel-Merle d'Aubigné score significantly improved from 10.5 preoperatively to 17.1 postoperatively.

Conclusions

The literature demonstrates satisfactory short-term outcomes with a mitigated risk of dislocation for DM used as primary THA in patients aged 55 years and younger. The current findings suggest that third-generation designs provide reduced rates of intraprosthetic dislocation and improved survivorship.

Survival and complications at a minimum 5years' follow-up of the modular Mark-2 Extreme™ cementless femoral stem: Does the reduced modularity resolve the mechanical issues of the Mark-I stem?

INTRODUCTION

The Extreme™ modular stem was developed for implant revision with metaphyseal-diaphyseal defect. Due to the high breakage rate, a new "reduced modularity" design has been introduced, but without reported results. We therefore conducted a retrospective assessment of (1) overall stem survival, (2) functional results, (3) osseointegration, and (4) the rate of complications, and notably of mechanical failure.

HYPOTHESIS

Reduced modularity reduces the risk of revision surgery for mechanical failure.

MATERIAL AND METHODS

Forty-five prostheses were implanted between January 2007 and December 2010 in 42 patients with severe bone defect (Paprosky≥III) or periprosthetic shaft fracture. Mean age was 69.6years (range: 44-91years). Minimum follow-up was 5years, for a mean 115.4months (range: 60-156months). The main study endpoint was femoral stem survival, counting all-cause explantation as event. Functional assessment comprised subjective rating of satisfaction, Postel Merle d'Aubigné (PMA) and Harris Hip scores, and Forgotten Joint Score (FJS). Whether the revision assembly was carried out in situ, in the patient's hip, or outside, on the operating table, was not known in 2 cases; in the other 43, assembly was in situ in 15 cases (35%) and on the operating table in 28 (65%).

RESULTS

Five-year stem survival was 75.7% (95% CI: 61.9-89.5%), taking all causes of change together. Seventeen patients (45.9%) had complications, 13 (35.1%) requiring revision surgery, including 10 (27.0%) for stem replacement. Five patients (13.5%) had steam breakage at the junction between the metaphysis and the diaphyseal stem, 4 of which occurred within 2 years of implantation or of fixation of a periprosthetic fracture. Mean preoperative Harris score was 48.4 [IQR (25-75% interquartile range): 37-58] and PMA score 11.1 (IQR: 10-12), compared to respectively 74 (IQR: 67-89) and 13.6 (IQR: 12.5-16) at follow-up. Mean FJS at follow-up was 71.5 (IQR: 61-94.5). In the 15 in situ assemblies, there were 3 breakages (20%), compared to 2 (7.1%) in the 28 table assemblies (p=0.21).

DISCUSSION

The stem breakage rate was high despite the reduced modularity, which concentrated all stress on a single junction but without reducing the risk of mechanical failure. Surgical technique was faulty in some cases, with in situ assembly of the metaphysis after implanting the diaphyseal stem, which does not respect the manufacturer's recommendations.

LEVEL OF EVIDENCE

IV; retrospective study.

Patient-Reported Outcomes Following Revision Total Hip Arthroplasty Demonstrate Less Improvement and Significantly Higher Rates of Worsening Compared to Primaries

BACKGROUND

Patient-reported outcome measures (PROMs) provide the patient's perspective following total hip arthroplasty (THA), although differences between primary THA (pTHA) and revision THA (rTHA) remain unclear. Thus, we compared the Minimal Clinically Important Difference for Improvement (MCID-I) and Worsening (MCID-W) in pTHA and rTHA patients.

METHODS

Data from 2,159 patients (1,995 pTHAs/164 rTHAs) who had completed Hip Disability and Osteoarthritis Outcome Score-Physical Function Short Form (HOOS-PS), Patient-Reported Outcomes Measurement Information System (PROMIS) Physical Function Short Form 10a (PF10a), PROMIS Global-Mental, or PROMIS Global-Physical questionnaires were analyzed. The PROMs and MCID-I/MCID-W rates were compared using statistical tests and multivariate logistic regressions.

RESULTS

Compared to the pTHA group, the rTHA group had lower rates of improvement and higher rates of worsening for almost all PROMs, including HOOS-PS (MCID-I: 54 versus 84%, P < .001; MCID-W: 24 versus 4.4%, P < .001), PF10a (MCID-I: 44 versus 73%, P < .001; MCID-W: 22 versus 5.9%, P < .001), PROMIS Global-Mental (MCID-W: 42 versus 28%, P < .001), and PROMIS Global-Physical (MCID-I: 41 versus 68%, P < .001; MCID-W: 26 versus 11%, P < .001). Odds ratios supported rates of worsening following revision for the HOOS-PS (Odds Ratio (OR): 8.25, 95% Confidence Interval (CI): 5.62 to 12.4, P < .001), PF10a (OR: 8.34, 95% CI: 5.63 to 12.6, P < .001), PROMIS Global-Mental (OR: 2.16, 95% CI: 1.41 to 3.34, P < .001), and PROMIS Global-Physical (OR: 3.69, 95% CI: 2.46 to 5.62, P < .001).

CONCLUSION

Patients reported higher rates of worsening and lower rates of improvement following rTHA than pTHA, with significantly less score improvement and lower postoperative scores for all PROMs after revision. Most patients reported improvements following pTHA, with few worsening postoperatively.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Combined structural allograft and tantalum cone to manage segmental metaphyseal tibial bone defect in revision knee arthroplasty

Tibial bone defect remains a challenge in revision knee arthroplasty. The present innovative technique combines structural allograft and tantalum metaphyseal cone for treatment of AORI stage 2A and 2B (uncontained peripheral metaphyseal) tibial defect. The aim is to reconstitute bone stock and enhance allograft osseointegration, while limiting stress to the allograft by implanting the metaphyseal cone through the allograft and the original bone. LEVEL OF EVIDENCE: V (expert opinion).

Decreasing trend of inpatient mortality rates of aseptic versus septic revision total hip arthroplasty: an analysis of 681,034 cases

BACKGROUND

While most revision total hip arthroplasties (rTHAs) are for aseptic loosening/instability, infection accounts for approximately 16%. The purpose of this study was to: (1) quantify mortality rates of aseptic versus septic rTHA; (2) determine if mortality rates have changed over the past 20 years; and (3) identify associated preoperative risk factors, focusing on the utility/validity of the Elixhauser comorbidity index (ECI).

METHODS

ICD-9/ICD-10 codes were used to identify patients undergoing rTHA in the National Inpatient Sample database between 1998 and 2017. A total of 681,034 cases (576,143 aseptic THA and 104,891 septic THA) were identified. For each patient, demographic variables including age, sex, race, insurance type, ECI, and inhospital mortality were gathered. A logistic regression model was constructed to assess risk of inhospital mortality.

RESULTS

From 1998 to 2017, inpatient mortality rates of aseptic and septic rTHA decreased from 0.83 to 0.45%, and from 2.58 to 1.24%, respectively. Septic rTHA was independently associated with higher odds of mortality relative to aseptic (odds ratio (OR): 2.305, 95% confidence interval (CI): (2.014, 2.638), p < 0.0001). Increased ECI was associated with higher odds of mortality at both medium (OR: 5.147, 95% CI: (4.433,5.977), p < 0.0001) and high index scores (OR: 13.714, 95% CI: (11.519,16.326), p < 0.0001).

CONCLUSIONS

Mortality rates for both aseptic and septic rTHA have been declining over the past 20 years, potentially due to patient selection guidelines and advances in medical management. Our study confirms that the ECI is independently associated with increased inpatient mortality.

Factors Associated With Failure Following Proximal Femoral Replacement for Salvage Hip Surgery for Nononcologic Indications

BACKGROUND

Proximal femoral replacement (PFR) is used when extensive proximal femoral bone loss is encountered during revision total hip arthroplasty. However, further data on 5-to-10-year survivorship and predictors of failure are needed. Our aim was to assess the survivorship of contemporary PFRs used for nononcologic indications and determine factors associated with failure.

METHODS

A single-institution retrospective observational study was conducted between June 1, 2010 and August 31, 2021 for patients undergoing PFR for non-neoplastic indications. Patients were followed for a minimum of 6 months. Demographic, operative, clinical, and radiographic data were collected. Implant survivorship was determined via Kaplan-Meier analysis of 56 consecutive cemented PFRs in 50 patients.

RESULTS

At a mean follow-up of 4 years, the mean Oxford Hip Score was 36.2 and patient satisfaction was rated at an average of 4.7 of 5 on the Likert scale. Radiographic evidence of femoral-sided aseptic loosening was determined in 2 PFRs at a median of 9.6 years. The 5-year survivorship with all-cause reoperation and revision as end points was 83.2% (95% Confidence Interval [CI]: 70.1% to 91.0%) and 84.9% (95% CI: 72.0% to 92.2%), respectively. The 5-year survivorship was 92.3% (95% CI: 78.0% to 97.5%) for stem length > 90 mm compared to 68.4% (95% CI: 39.5% to 85.7%) for stem length ≤ 90 mm. A construct-to-stem length ratio (CSR) ≤ 1 was associated with a 91.7% (95% CI: 76.4% to 97.2%) survival, while a CSR > 1 was associated with a 73.6% (95% CI: 47.4% to 88.1%) survival.

CONCLUSION

A PFR stem length ≤ 90 mm and CSR > 1 were associated with increased rates of failure.

Postoperative Outcomes in Total Hip and Total Knee Arthroplasty for Patients Who Have Multiple Myeloma

BACKGROUND

Advancements in oncologic care have increased the longevity of patients who have multiple myeloma, although outcomes beyond the early postoperative period following total hip arthroplasty (THA) and total knee arthroplasty (TKA) remain unknown. This study investigated the influence of preoperative factors on implant survivorship following THA and TKA after a minimum 1-year interval for multiple myeloma patients.

METHODS

Using our institutional database, we identified 104 patients (78 THAs, 26 TKAs) from 2000 to 2021 diagnosed with multiple myeloma before their index arthroplasty by International Classification of Diseases, Ninth and Tenth Revisions (ICD-9 and ICD-10) codes 203.0× and C90.0× and corresponding Current Procedural Terminology (CPT) codes. Demographic data, oncologic treatments, and operative variables were collected. Multivariate logistic regressions assessed variables of interest, and Kaplan-Meier curves were used to estimate implant survival.

RESULTS

There were 9 (11.5%) patients who underwent revision THA after an average time of 1,312 days (range, 14 to 5,763), with infection (33.3%), periprosthetic fracture (22.2%), and instability (22.2%) being the most common indications. Of these patients, 3 (33.3%) underwent multiple revision surgeries. There was 1 (3.8%) patient who underwent revision TKA at 74 days postoperatively for infection. Patients treated with radiotherapy were more likely to require revision THA (odds Rratio (OR): 6.551, 95% confidence interval (CI): 1.148-53.365, P = .045), but no predictors of failure were identified for TKA patients.

CONCLUSION

Orthopaedic surgeons should know that multiple myeloma patients have a relatively high risk of revision, particularly following THA. Accordingly, patients who have risk factors for failure should be identified preoperatively to avoid poor outcomes.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Ethical Considerations in Total Joint Arthroplasty

Hip and knee arthroplasty surgeries have excellent outcomes and notably improve quality of life. However, ethical issues permeate the practice of adult reconstruction, and as economics and technology evolve, these issues have become increasingly important. This article will review the currently published literature on ethical issues including industry influences, implants and instrumentations, surgical innovation, new technology adoptions, and healthcare policy-relevant issues, including patient cost sharing and bundled care programs. In addition, the direct marketing of implants from the manufacturer to the general public may falsely raise patient expectations concerning the long-term clinical outcome and performance of newer devices in the absence of long-term studies. This article will also focus on relevant contemporary ethical issues that do not necessarily have preexisting published literature or guidelines but, nonetheless, are crucial for adult reconstruction surgeons to address. These issues include access to care and challenges with orthopaedic resident and fellow education. Surgeons must understand the ethical issues that can arise in their clinical practice and how those issues affect patients. Clinicians are tasked with making the best-reasoned judgment possible to optimize their patients' outcomes. Still, the ability to standardize treatment while optimizing individual outcomes for unique patients remains a challenge.

Removing Cemented Dual Mobility Liners From Acetabular Components: A Technical Tip for a Challenging Surgical Problem

Dislocation remains the leading cause of failure following revision total hip arthroplasty. Dual mobility (DM) constructs, including monoblock cups designed for cementation, reduce but do not eliminate this risk. Cemented DM constructs offer several unique advantages in revision total hip arthroplasty, and as such, they have gained popularity. Despite their advantages, a portion of these implants will require revision for infection or recurrent dislocation. Removal of a cemented DM cup presents numerous challenges, and there is no effective published technique. Here, we present an effective technique for the safe removal of one design of cemented DM cup.

Feasibility and anteversion accuracy of a patient-specific instrument for femoral prosthesis implantation in total hip arthroplasty

BACKGROUND

The aim of this study was to evaluate the precision and feasibility of patient-specific instruments (PSI) in total hip arthroplasty (THA) as compared to the traditional free-hand (FRH) approach.

METHODS

During the period of January 1, 2021 to December 31, 2022, a randomized allocation was used for patients receiving unilateral primary THA to either the PSI or conventional operation group. The placement and size of the PSI were specifically chosen to guide femoral neck resection and prosthesis implantation. The study analyzed component positions and evaluated radiographic and clinical outcomes in 30 patients who received PSI-assisted THAs and 30 patients who received FRH THAs. This study was registered at China Clinical Trial Registry (number: ChiCTR2300072325) on June 9th, 2023.

RESULTS

The use of PSI in THA resulted in significantly higher precision in achieving the desired component position as compared to the FRH approach. The PSI group showed significantly smaller absolute errors of femoral anteversion (p < 0.001). No significant differences were found in operation time, intra-operative blood loss, hospitalization duration, or time to walk after surgery.

CONCLUSION

In conclusion, the application of patient-specific instruments in THA provides a simple and reliable solution to enhance the precision of femoral prosthesis placement with high accuracy and feasibility. This study highlights the potential benefits of using the PSI in THA.

Trochanteric Bolt Failure in a Modular Femoral Revision System

With the incidence of primary total hip arthroplasty continuing to rise in the United States, the innovation behind improving current total hip arthroplasty systems inevitably grows with it-each new design potentially ushering in new flaws. We report a case of screw failure with the Arcos Modular Femoral Revision System-Trochanteric Bolt and Claw Technique in a 74-year-old male patient. The patient presented to the investigator's clinic for their 20-month follow-up evaluation of their complex right hip revision. Radiographs revealed failure of the screw attaching the claw plate to the stem resulting in dislodgement and relocation of the screw within the intra-articular cavity. The patient elected for nonsurgical management and will continue to be monitored. Consent by the patient involved in this case report was obtained.

Two-stage revision in periprosthetic joint infection of the hip using a new intraoperatively molded articulating spacer design

Purpose

The treatment of periprosthetic joint infection (PJI) after total hip arthroplasty (THA) is still under debate. Two-stage exchange arthroplasty is the most common surgical procedure performed. This study analyzed a new functional articulating hip spacer called "Spaceflex" regarding the mechanical-related complications, the recurrent/persistent infection during the interval period, the overall infection-free survivorship after reimplantation, the overall complication/reoperation after reimplantation and the evaluation of patient-reported outcome measures (PROMs) at three intervals of time: before the first stage, during the interval period, and at the final follow-up after reimplantation.

Methods

A consecutive series of 56 patients with chronic hip PJI undergoing two-stage prosthetic revision using a new intraoperatively molded articulating hip spacer design implanted by the same experienced surgeons was examined from January 2017 to December 2021. The demographic and clinical characteristics of the included patients were analyzed. Specifically, PROMs before the first stage, during the interval period, and at the final follow-up after reimplantation and complications reported during the interval period and after reimplantation were examined.

Results

The new functional articulating hip spacer was characterized by a low mechanical complication rate (5.8%) and an overall two-stage procedure success rate of 90.6% at the last follow-up. PROMs improved with the spacer during the interval period and at the final follow-up. Furthermore, the reinfection rate was in line with other case series with different spacer designs. Finally, low postoperative complication rates after reimplantation have been demonstrated.

Conclusions

Two-stage revision performed with a modular articulating spacer allows patients to preserve satisfactory functional and quality-of-life outcomes in the postoperative period, with a low risk of mechanical complications and without increasing the reinfection rate.

Novel diagnostic markers for periprosthetic joint infection: a systematic review

Background

Identifying novel biomarkers that are both specific and sensitive to periprosthetic joint infection (PJI) has the potential to improve diagnostic accuracy and ultimately enhance patient outcomes. Therefore, the aim of this systematic review is to identify and evaluate the effectiveness of novel biomarkers for the diagnosis of PJI.

Methods

We searched the MEDLINE, EMBASE, PubMed, and Cochrane Library databases from January 1, 2018, to September 30, 2022, using the search terms "periprosthetic joint infection," "prosthetic joint infection," or "periprosthetic infection" as the diagnosis of interest and the target index, combined with the term "marker." We excluded articles that mentioned established biomarkers such as CRP, ESR, Interleukin 6, Alpha defensin, PCT (procalcitonin), and LC (leucocyte cell count). We used the MSIS, ICM, or EBJS criteria for PJI as the reference standard during quality assessment.

Results

We collected 19 studies that analyzed fourteen different novel biomarkers. Proteins were the most commonly analyzed biomarkers (nine studies), followed by molecules (three studies), exosomes (two studies), DNA (two studies), interleukins (one study), and lysosomes (one study). Calprotectin was a frequently analyzed and promising marker. In the scenario where the threshold was set at ≥50-mg/mL, the calprotectin point-of-care (POC) performance showed a high sensitivity of 98.1% and a specificity of 95.7%.

Conclusion

None of the analyzed biomarkers demonstrated outstanding performance compared to the established parameters used for standardized treatment based on established PJI definitions. Further studies are needed to determine the benefit and usefulness of implementing new biomarkers in diagnostic PJI settings.

Declining Geographic Access to High-Volume Revision Total Hip Arthroplasty Surgeons: A National Medicare Analysis

BACKGROUND

While trends in the economics of revision THA (revTHA) procedures have been well-described from the standpoint of both hospitals and surgeons, their population-level effects of these trends on patient access are not well-understood.

METHODS

The Medicare fee-for-service provider utilization and payment public use files were used to extract data for primary and revTHA for beneficiaries between 2013 and 2019. Primary and revTHA procedures were identified using the Healthcare Common Procedure Coding System code; 27130 for primaries and 27132, 27134, 27137, or 27138 for revisions. Geospatial analyses were performed by aggregating surgeon practice locations at the level of individual counties, hospital service areas, and hospital referral regions.

RESULTS

The number of high-volume primary THA surgeons within the Medicare population increased by 17.6% over the study period (3,838 in 2013 to 4,515 in 2019). Conversely, the number of high-volume revTHA surgeons decreased by 36.1% (178 in 2013 to 129 in 2019). Linear regression revealed a significant increase and decrease in high-volume primary (β = 109.07, P ≤ .001) and revision (β = -13.04, P = .011) THA surgeons, respectively. Over the study period, the number of counties with at least 1 high-volume primary THA surgeon increased by 6.1% (1,194 to 1,267), while the number of counties with at least 1 high-volume revTHA surgeon decreased by 30.2% (159 to 111).

CONCLUSION

The present findings of declining geographic access may represent a consequence of shifting economic incentives and declining reimbursements for the care of complicated revTHA patients.

Understanding the 30-day mortality burden after revision total hip arthroplasty

BACKGROUND

Revision total hip arthroplasty (THA) is a challenging procedure that burdens the healthcare system. Despite being associated with worse outcomes relative to its primary counterpart, postoperative mortality after revision THA remains ill-defined. The present study aimed to (1) establish the overall 30-day mortality rate after revision THA and (2) explore the mortality rate stratified by age, comorbidity burden, and aseptic versus septic failure.

METHODS

The American College of Surgeons - National Surgical Quality Improvement Program (ACS-NSQIP) database was retrospectively reviewed for all patients who underwent revision THA from 2011 to 2019. A total of 23,501 patients were identified and grouped into mortality (n = 161) and mortality-free (n = 23,340) cohorts. Patient demographics, comorbidities, and aseptic/septic failure were evaluated.

RESULTS

The overall 30-day mortality was 0.69%. The mortality rate by age group (normalised per 1000 patients) was 0 (18-39 years [Y]), 0.67 (40-49 Y), 1.10 (50-59 Y), 2.58 (60-69 Y), 6.15 (70-79 Y) 19.32 (80-89 Y), and 58.22 (90+Y) (p < 0.001). The mortality rate by ASA classification (normalised per 1000 patients) was 0 (ASA I), 1.47 (ASA II), 6.94 (ASA III), 45.42 (ASA IV), and 200 (ASA V) (p < 0.001). The 30-day mortality rate for the septic and aseptic cohorts was 1.03% and 0.65%, respectively (p = 0.038). CCI scores (p < 0.001), diabetes (p < 0.001), systematic sepsis (p < 0.001), poor functional status (p < 0.001), BMI < 24.9 kg/m2 (p < 0.001), and dirty/infected wounds (p < 0.001) were all associated with increased mortality risk.

CONCLUSIONS

1 in 145 patients will suffer mortality during the 30 days after revision THA. PJI-related revision THA was associated with 1.5-fold increase in 30-day mortality rate compared to its aseptic counterpart. Certain patient determinants and baseline comorbidities, as measured by ASA and CCI scores, were associated with higher 30-day mortality rates. Therefore, it is imperative to identify such risk factors and implement perioperative patient optimisation pathways to mitigate the risk among vulnerable patients.

Did the dislocation risk after primary total hip arthroplasty decrease over time? A meta-analysis across six decades

BACKGROUND

While continuous optimization is attempted to decrease the incidence of dislocation after total hip arthroplasty (THA), dislocation remains a major complication. This meta-analysis aims to analyze the evolution of the dislocation risk after primary THA over the decades and to evaluate its potential publication bias.

PATIENTS AND METHODS

A systematic search was performed according to the PRISMA guidelines for this meta-analysis in the literature published between 1962 and 2020. MEDLINE, Cochrane and Embase databases were searched for studies reporting the dislocation risk and length of follow-up. Studies that reported on revision rates only and did not mention separate dislocations were excluded. All study designs were eligible. Study quality was assessed by existing quality assessment tools adjusted for arthroplasty research. Overall risk and yearly dislocation rates were calculated and related to historical time frame, study design, sample size and length of follow-up.

RESULTS

In total, 174 studies were included with an overall moderate quality. In total there were 85.209 dislocations reported in 5.030.293 THAs, showing an overall dislocation risk of 1.7%, with a median follow-up of 24 months. The overall dislocation risk classified per decade decreased from 3.7% in 1960-1970 to 0.7% in 2010-2020. The yearly dislocation rate decreased from 1.8 to 0.7% within these same decades. There was no significant correlation between the reported dislocation risk and the duration of follow-up (p = 0.903) or sample size (p = 0.755). The reported dislocation risk was higher in articles with registry data compared to other study designs (p = 0.021).

CONCLUSION

The dislocation risk in THA has been decreasing over the past decades to 0.7%. Non-selective registry studies reported a higher dislocation risk compared to studies with selective cohorts and RCTs. This indicates that the actual dislocation risk is higher than often reported and 'real-world data' are reflected better in large-scale cohorts and registries.

Computer-Assisted Navigation Accurately Delivers Preoperative Targets for Acetabular Component Orientation During Direct Anterior Approach Total Hip Arthroplasty

Despite its success, total hip arthroplasty (THA) remains associated with potentially significant complications associated with component malposition. Preoperative planning can mitigate some of these potential concerns; however, the accurate intraoperative delivery of preoperative targets can be challenging. Computer-assisted navigation may assist with intraoperative target delivery, although the integration of these two technologies is relatively uncommon. We retrospectively reviewed cases of THA planned with a computed tomography-based preoperative planning software and performed with the use of an imageless, computer-assisted navigation system. Postoperative acetabular component orientation from radiographs was compared with preoperative targets and intraoperative navigation measurements. A total of 76 patients were included in the analysis. The mean anteversion target (20.0°±3.1°) did not differ significantly from the mean intraoperative navigation measurement (20.5°±3.3°; P=.30; mean difference, 2.2°±2.3°). The mean radiographic measurement (26.6°±6.5°) differed from the target by a mean of 7.5°±6.1° (P<.001). The mean inclination target (38.4°±1.9°) did not differ significantly from the mean intra-operative measurement (38.0°±1.5°; P=.20; mean difference, 1.3°±1.7°) but differed from the radiographic measurement by a mean of 5.2°±4.2° (41.8°±5.6°; P<.001). No adverse events were reported in the 90-day period following the index procedure. Our study demonstrated that an imageless navigation system can accurately deliver computed tomography-derived preoperative targets for acetabular component orientation. Differences noted on radiographs may be due to the difference in patient positioning for the postoperative imaging (standing) as compared with preoperative imaging or surgery itself (supine). [Orthopedics. 2023;46(4):218-223.].

Contemporary mortality rate and outcomes in nonagenarians after aseptic revision hip and knee arthroplasty

Aims

Nonagenarians (aged 90 to 99 years) have experienced the fastest percent decile population growth in the USA recently, with a consequent increase in the prevalence of nonagenarians living with joint arthroplasties. As such, the number of revision total hip arthroplasties (THAs) and total knee arthroplasties (TKAs) in nonagenarians is expected to increase. We aimed to determine the mortality rate, implant survivorship, and complications of nonagenarians undergoing aseptic revision THAs and revision TKAs.

Methods

Our institutional total joint registry was used to identify 96 nonagenarians who underwent 97 aseptic revisions (78 hips and 19 knees) between 1997 and 2018. The most common indications were aseptic loosening and periprosthetic fracture for both revision THAs and revision TKAs. Mean age at revision was 92 years (90 to 98), mean BMI was 27 kg/m² (16 to 47), and 67% (n = 65) were female. Mean time between primary and revision was 18 years (SD 9). Kaplan-Meier survival was used for patient mortality, and compared to age- and sex-matched control populations. Reoperation risk was assessed using cumulative incidence with death as a competing risk. Mean follow-up was five years.

Results

Mortality rates were 9%, 18%, 26%, and 62% at 90 days, one year, two years, and five years, respectively, but similar to control populations. There were 43 surgical complications and five reoperations, resulting in a cumulative incidence of reoperation of 4% at five years. Medical complications were common, with a cumulative incidence of 65% at 90 days. Revisions for periprosthetic fractures were associated with higher mortality and higher 90-day risk of medical complications compared to revisions for aseptic loosening.

Conclusion

Contemporary revision THAs and TKAs appeared to be relatively safe in selected nonagenarians managed with multidisciplinary teams. Cause of revision affected morbidity and mortality risks. While early medical and surgical complications were frequent, they seldom resulted in reoperation.

Comparison of Clinical and Functional Outcomes in One versus Two Component Revision for Total Knee Arthroplasty

BACKGROUND

Revisions of total knee arthroplasties (TKAs) may require revision of one or both tibial and femoral components. Our purpose was to examine the clinical and functional outcomes in 1- versus 2-component TKA revisions.

METHODS

We identified 92 1-component (tibial or femoral) revisions at a single center. Our inclusion criteria were isolated revision of the tibial or femoral components with a minimum 2-year follow-up. The included cases were matched 1:2 with a control group of 2-component revisions (tibial and femoral) by age, body mass index, American Society of Anesthesiologists score, and indication for revision. We collected demographics, complications, operative times, any subsequent rerevisions, and functional outcome scores.

RESULTS

The median follow-up time for the 1- and 2-component revision groups were 10 years (range, 3 to 17) and 8 years (range, 2 to 18), respectively. The most common complication after rerevision in both groups was stiffness at 9 of 92 (9.8%) and 9 of 170 (5.3%) in the 1- and 2-component groups, respectively (P = .20). The overall complication prevalence in the 1- and 2- component revision groups was similar 20 of 92 (22%) and 35 of 170 (21%), respectively (P = .87). Subsequent rerevisions for any indication were encountered in 12 of 92 (13.0%) of the 1-component and 18 of 170 (11%) in the 2-component groups (P = .69). There was no statistical difference in survivorship or functional outcomes scores between the groups.

CONCLUSION

Our results showed that isolated revision of a single TKA component is an acceptable option, with comparable functional outcomes, complications, and survivorships when compared with both-component revision. As such, a 1-component revision should be considered where appropriate.

Dual-Action Effect of Gallium and Silver Providing Osseointegration and Antibacterial Properties to Calcium Titanate Coatings on Porous Titanium Implants

Previously, functional coatings on 3D-printed titanium implants were developed to improve their biointegration by separately incorporating Ga and Ag on the biomaterial surface. Now, a thermochemical treatment modification is proposed to study the effect of their simultaneous incorporation. Different concentrations of AgNO₃ and Ga(NO₃)₃ are evaluated, and the obtained surfaces are completely characterized. Ion release, cytotoxicity, and bioactivity studies complement the characterization. The provided antibacterial effect of the surfaces is analyzed, and cell response is assessed by the study of SaOS-2 cell adhesion, proliferation, and differentiation. The Ti surface doping is confirmed by the formation of Ga-containing Ca titanates and nanoparticles of metallic Ag within the titanate coating. The surfaces generated with all combinations of AgNO₃ and Ga(NO₃)₃ concentrations show bioactivity. The bacterial assay confirms a strong bactericidal impact achieved by the effect of both Ga and Ag present on the surface, especially for Pseudomonas aeruginosa, one of the main pathogens involved in orthopedic implant failures. SaOS-2 cells adhere and proliferate on the Ga/Ag-doped Ti surfaces, and the presence of gallium favors cell differentiation. The dual effect of both metallic agents doping the titanium surface provides bioactivity while protecting the biomaterial from the most frequent pathogens in implantology.

The risk of hospital readmission, revision, and intra- and postoperative complications between direct anterior versus posterior approaches in primary total hip arthroplasty: a stratified meta-analysis and a probability based cost projection

INTRODUCTION

This study presents stratified meta-analysis and projected cost per case analysis of direct anterior approach (DAA) versus posterior approach (PA) in total hip arthroplasty (THA) to determine the best surgical approach and guarantee hip joint longevity.

METHODS

Several online databases were searched for clinical trials comparing DAA and PA in primary THA. The stratified analysis was conducted to test for confounding and biases across the different types of included trials. The average cost and probability were used to determine projected added costs of medical and surgical management for complications.

RESULTS

30 clinical trials included 11,562 patients who underwent THA. Almost 50% of these patients performed DAA. As compared to PA, both non-stratified and stratified analyses demonstrated that DAA has a significant higher incidence of the overall intra- and postoperative complications (non-stratified, OR 1.64; p = 0.003) (stratified, OR 4.12; p = 0.005), nerve injury (non-stratified, OR 22.0; p < 0.00001) (stratified, OR 0.28; p < 0.00001), higher rate of revision surgery (non-stratified; OR 1.54; p = 0.01) (stratified, OR 7.37; p = 0.006), and higher incidence of surgical wound complications (non-stratified; OR 1.67; p = 0.002) as compared to PA following primary THA. In addition, DAA demonstrated higher trends of incidence (non-statistically significant) of femur fracture (Non-stratified, OR 1.32, p = 0.10) and thrombo-embolic complications (Retrospective studies, OR 1.39, p = 0.69). However, PA demonstrated higher trends of incidence (non-statistically significant) of hip joint dislocation, as compared to DAA. (Stratified RCTs, OR 0.63, p = 0.65]. Collectively, this amounts a $421,068.68 surplus in DAA complication costs.

CONCLUSIONS

PA may provide a more lucrative, safer approach to those undergoing THA given its comparable postoperative outcomes, reduced complication rates, and lower overall cost relative to DAA.

Registry Data Show Complication Rates and Cost in Revision Hip Arthroplasty

INTRODUCTION

Revision THA (rTHA) places a burden on patients, surgeons, and health care systems because outcomes and costs are less predictable than primary THA. The purposes of this study were to define indications and treatments for rTHA, quantify risk for readmissions and evaluate the economic impacts of rTHA in a hospital system.

METHODS

The arthroplasty database of a hospital system was queried to generate a retrospective cohort of 793 rTHA procedures, performed on 518 patients, from 2017 to 2019 at 27 hospitals. Surgeons performed chart reviews to classify indication and revision procedure. Demographics, lengths of stay (LOS), discharge dispositions, and readmission data were collected. Analyses of direct costs were performed and categorized by revision type.

RESULTS

46.3% of patients presented for infection. Patients presenting for infection were 5.6 times more likely to have repeat rTHA than aseptic patients. Septic cases (4.3 days) had longer LOS than aseptic ones (2.4) (P < 0.0001). 31% of patients discharged to a skilled nursing facility (SNF). Direct costs were greatest for a two-stage exchange ($37,642), and lowest for liner revision ($8,979). Septic revisions ($17,696) cost more than aseptic revisions ($11,204) (P< 0.0001). The 90-day readmission rate was 21.8%. Septic revisions had more readmissions (13.5%) than aseptic revisions (8.3%).

CONCLUSIONS

Hip revisions, especially for infection, have an increased risk profile and create a major economic impact on hospital systems. Surgeons may use these data to counsel patients on risks of rTHA and advocate for improved reimbursement for the care of revision patients.

Do 'Surgeon Champions' and High-Volume Surgeons Have Lower Rates of Periprosthetic Femur Fracture? Perspective from a State-wide Quality Improvement Registry

BACKGROUND

Recently, a state-wide registry identified fracture as a major cause of total hip arthroplasty revision. There were 52.8% of revisions occurring within 6 months (fracture leading cause). Registry sites have a 'Surgeon Champion' who acts as liaison and advocate. This study evaluated the effect of surgeon volume and role of 'surgeon champion' on fracture rates.

METHODS

There were 95,948 cases from 2012 to 2019 queried with peri-implant femoral fractures identified (within 6 months). Funnel plots were generated to compare individual surgeon-specific fracture rates. Surgeons who had a fracture rate below the confidence interval were labeled 'green' (lower than mean), within were 'yellow' (no difference), and above were 'red' (significantly higher).

RESULTS

For all surgeons, 19.6% were red, 72.1% yellow, and 8.3% green. There were 17.2% 'Surgeon Champions' and 6.2% 'Non-Champions' that were green (P=0.01), while 20.7 and 19.3% were red (P=0.82). There was a significant association between volume and performance (P<0.01). No surgeons in the lower two quartiles (<84; 84 to 180 cases), while 4 and 29% of higher-volume surgeons (181 to 404; >404 cases) were green. There was no statistical difference in red status by volume (P=0.53).

CONCLUSION

'Surgeon champions' and high-volume surgeons were more likely to be high performers, but not less-likely to be low performers. Active involvement in quality improvement and/or high-volume was associated with better outcomes, but did not impart complication immunity. 'Green' surgeons should mentor colleagues to help reduce fractures by re-evaluating modifiable factors. Analyzing outcomes to promote quality and decrease complications is paramount.

The Correlation Between Pelvic Motion and Lumbar Motion in Patients Presenting With a Lumbar Spinal Pathology: Implications for Assessing Dislocation Risk in Total Hip Arthroplasty

Background

Arthroplasty surgeons use the change in sacral slope (ΔSS) from sitting to standing as a measure of spinal motion. The relationship between ΔSS and the change in lumbar lordosis (ΔLL), an established spinal motion measure, has not been well studied. This study aims to determine the correlation between ΔSS and ΔLL.

Methods

Consecutive patients presenting to a spine clinic from 2020 to 2021 at a single institution were retrospectively studied. Standing and sitting lateral radiographs were measured for SS and LL. Patients were divided using ΔSS and ΔLL into stiff (0°-9°), normal (10°-30°), or hypermobile (>30°) category. Patients with a ΔSS-determined normal or hypermobile spine but a ΔLL-determined stiff spine were compared to the rest of the cohort.

Results

Overall, 100 patients were included. Of these patients, 47% had the same classification when looking at ΔSS and ΔLL, whereas 53% had conflicting classifications. Twenty percent of patients had a ΔSS-determined normal or hypermobile spine but ΔLL-determined stiff spine. The correlation between ΔSS and ΔLL was 0.510 (P < .001). When isolating patients who underwent lumbar fusion, the correlation between ΔSS and ΔLL was 0.345 (P < .001).

Conclusions

ΔSS has a moderate correlation with ΔLL in patients presenting for evaluation of their lumbar spine but low correlation in patients with lumbar fusion. In our cohort, 20% of patients had a ΔSS-determined normal or hypermobile spine but a ΔLL-determined stiff spine, representing a potential high-risk dislocation cohort not captured by ΔSS alone. Arthroplasty surgeons should revisit classifying spinal motion based solely on ΔSS.

The diagnostic value of blood sample NGS in patients with early periprosthetic joint infection after total hip arthroplasty

The diagnostic value of next-generation sequencing (NGS) of blood samples from patients with periprosthetic joint infection (PJI) after total hip arthroplasty (THA) was evaluated by comparing it with drainage fluid NGS and bacterial culture. The study was designed as a retrospective diagnostic test. Thirty-six infected patients were diagnosed with PJI according to the Musculoskeletal Infection Society (MSIS) criteria and 57 volunteers were included in our study. NGS and bacterial culture were chosen to detect PJI after THA. Blood samples and drainage fluid were collected for NGS, and the drainage fluid, which was collected at the same time as the NGS drainage fluid sample, was used for bacterial culture. The primary outcomes of interest were sensitivity, specificity, and accuracy. In the infection group, 31 patients showed positive results by blood sample NGS, 33 patients showed positive results by drainage fluid NGS, and 17 patients showed positive bacterial culture results. In the control group, the results of 2 blood sample NGS, 16 drainage fluid NGS, and 3 bacterial cultures were positive. The sensitivity, specificity, and accuracy of the blood sample were 0.86, 0.96, and 0.92, respectively. The sensitivity, specificity, and accuracy of the drainage fluid samples were 0.92, 0.72, and 0.80, respectively. The sensitivity, specificity, and accuracy of bacterial culture were 0.47, 0.95, and 0.79, respectively. The study demonstrated that both the sensitivity and specificity of NGS were higher than those of bacterial culture, regardless of the kind of sample. Compared with drainage fluid NGS, the sensitivity of blood sample NGS was slightly lower (0.86 vs 0.92), but blood sample NGS showed higher specificity (0.96 vs 0.72). In total, the diagnostic value of blood sample NGS was superior to that of drainage fluid NGS and bacterial culture. The majority of infected patients could be identified by blood sample NGS. Moreover, because of its high specificity, blood sample NGS can not only detect infectious bacteria but also distinguish infectious from non-infectious bacteria, which is dramatically different from using drainage fluid NGS.