Complications After Revision Total Hip Arthroplasty in the Medicare Population

Arthroscopic sampling, diagnosis and treatment of infected total hip replacements in dogs: Eight cases

OBJECTIVE

To describe the technique and long-term outcomes in a group of eight dogs undergoing arthroscopic debridement with implant retention or subsequent revision surgery for total hip replacement (THR) infection.

STUDY DESIGN

Short case series.

METHODS

Dogs underwent a THR procedure and subsequently developed signs consistent with a periprosthetic joint infection (PJI). Two groups of subjects were identified: those where the procedure had curative intent to resolve the infection with retention of implants (CI group) and those where the procedure was diagnostic in nature but also may have included various debulking procedures (NCI group). Dogs underwent an arthroscopic procedure that included sample collection, partial synovectomy, high volume lavage and other antimicrobial therapies.

RESULTS

Five dogs were treated in the CI group, four of which had no recurrence of infection during the reporting period. In the NCI group, three dogs underwent arthroscopic debridement and debulking procedures prior to planned revision surgeries. Arthroscopically obtained samples produced positive cultures in four of five dogs in the CI group and one of three dogs in the NCI group. Arthroscopic treatment of PJIs was associated with a successful outcome in seven of eight dogs in this case series.

CONCLUSION

Arthroscopic treatment of PJIs was successful in four of five cases (80%) of dogs in the CI group, which is consistent with that reported in humans. Arthroscopic sampling for bacteria culture had good sensitivity for type 1 PJIs and poor sensitivity for type 2 PJIs.

Primary Total Hip Arthroplasty Achieves Minimal Clinically Important Difference Faster than Revision Total Hip Arthroplasty

BACKGROUND

Despite the prevalence of total hip arthroplasty (THA) as a treatment for hip-related conditions, there is limited research directly comparing the patient-reported outcome measures between primary and revision total hip arthroplasty (rTHA). This study compared the time to achieve minimal clinically important difference (MCID) between primary and rTHA.

METHODS

We conducted a retrospective analysis comparing 6,671 THAs (6,070 primary and 601 all-cause rTHAs) performed between 2016 and 2022. Patient-reported outcomes were evaluated using preoperative and postoperative scores of Patient-Reported Outcomes Measurement Information System (PROMIS) Global Physical, PROMIS Physical Function Short Form 10a (PF-10a), and Hip Injury and Osteoarthritis Outcome Score - Physical Function Short Form (HOOS-PS). The time to achieve MCID was assessed using survival curves with and without interval-censoring, and statistical comparisons were performed using log-rank and weighted log-rank tests.

RESULTS

Comparing the time to achieve MCID without interval-censoring, primary total hip arthroplasty (pTHA) demonstrated significantly faster median times than rTHA for PROMIS Global Physical (3.3 versus 3.9 months, P < 0.001), PROMIS PF-10a (3.6 versus 6.2 months, P < 0.001), and HOOS-PS (3.1 versus 4.0 months, P < 0.001). Similarly, when using interval-censoring, pTHA continued to achieve MCID significantly faster than rTHA for PROMIS Global Physical (0.23 to 0.24 versus 0.50 to 0.51 months, P < 0.001), PROMIS PF-10a (1.43 to 1.44 versus 3.03 to 3.04 months, P < 0.001), and HOOS-PS (0.87 to 0.87 versus 1.20 to 1.21 months, P < 0.001).

CONCLUSIONS

Across all patient-reported outcome measures, pTHA achieved MCID significantly faster than rTHA, irrespective of interval-censoring. These findings underscore the importance of setting realistic postoperative recovery expectations during perioperative patient counseling. Future studies should investigate the factors influencing time to achieve MCID and explore how to enhance rTHA techniques and perioperative management for improved patient outcomes.

LEVEL OF EVIDENCE

III.

What Factors Influence In-Hospital Mortality Following Aseptic Revision Total Hip Arthroplasty? A Single-Center Analysis of 13,203 Patients

BACKGROUND

Revision total hip arthroplasty (rTHA) is associated with an extended surgical period, an increased hospitalization period, expanded blood loss, and high mortality rates. The purpose of the present study was to assess the risk factors that contribute to in-hospital mortality following aseptic rTHA.

METHODS

We performed a retrospective examination of the medical records of all patients who underwent elective rTHA surgery at our tertiary referral arthroplasty center between March 1996 and March 2019. The study involved a group of 13,203 patients, including 70 who expired during hospitalization and 13,133 in the control group. Baseline characteristics, medical history, comorbidities, and surgery-related parameters of the patients were recorded. Logistic regression analyses were performed to examine the association between independent variables and in-hospital mortalities, which were presented as odds ratios (ORs) and confidence intervals (CIs).

RESULTS

Patient factors associated with in-hospital mortality included hepatitis C (OR 75.5, 95% CI 3.5 to 1,625.2), chronic obstructive pulmonary disease (OR 30.7, 95% CI 6.5 to 145.7), rheumatoid arthritis (OR 28.9, 95% CI 3.8 to 218.5), history of myocardial infarction (OR 24.9, 95% CI 4.4 to 140.8), history of cerebrovascular disease (OR 23.1, 95% CI 3.8 to 142), congestive heart failure (OR 18.9, 95% CI 3.8 to 94.2), and diabetes mellitus (OR 10.2, 95% CI 2.4 to 42.6). Surgical factors included the history of multiple prior revisions (OR 1.75, 95% CI 1.1 to 2.7), postoperative blood transfusion (OR 2.8, 95% CI 1.1 to 7.3), and decreased preoperative hemoglobin (OR 2.3, 95% CI 1.7 to 3.1).

CONCLUSIONS

Several patient-related and intraoperative factors significantly increased the risk of in-hospital mortality following aseptic rTHA. Vigilance and close perioperative monitoring are essential for patients undergoing this complex surgery.

LEVEL OF EVIDENCE

III.

A Registry Study on Acetabular Revisions Using Jumbo Cups: Do We Really Need a More Complex Revision Strategy?

BACKGROUND

The increasing global performance of total hip arthroplasty (THA) has led to a rise in revision surgeries, primarily due to cup failure, with aseptic loosening and periprosthetic infection being common causes. Various techniques and implants, including jumbo cups (JCs), manage residual bone loss post-cup removal, facilitating enhanced surface area for improved host bone contact, and osteointegration. The purpose of the study was to determine the outcomes of acetabular revision arthroplasty using JC implants over a 20-year follow-up period by reporting overall survivorships, complications leading to re-revision, and surgical strategies in re-revision.

METHODS

A cohort study based on a large regional registry was conducted, examining revision THA surgeries utilizing JCs between 2000 and 2020. The study included all the revision acetabular procedures performed with cementless JCs, identified with a diameter ≥ 62 millimeters (mm) in women or ≥ 66 mm in men. All iliac fixation cups were excluded. Data on demographics, revision surgery indications, components, fixation types, causes of failure, and reintervention strategies were collected and analyzed. A total of 541 JCs implanted from January 2000 to December 2020 were evaluated. The most common revision indications were "cup aseptic loosening" (54.5%) and "total aseptic loosening," which included both the cup and stem (32%).

RESULTS

The JC survival rates were 92.5% at 5 years, 85.8% at 10 years, and 81.5% at 15 years. Among the 70 failures, the main causes were "cup aseptic loosening" (40%), "total aseptic loosening" (17.1%), and "septic loosening" (12.8%). Revisions primarily involved acetabular cup revision surgery (54 cases), component explantation (11 cases), or insert or head revision (five cases).

CONCLUSIONS

This registry-based study of JCs in revision THA demonstrates excellent 15-year survival rates and acceptable failure rates. It supports JCs as a viable option, offering relative surgical simplicity compared to alternatives like antiprotrusion cages, bone grafts, and augments.

Not so Fast! Feasibility and Safety of Outpatient Revision Total Hip Arthroplasty

BACKGROUND

As total hip arthroplasty (THA) transitions to the outpatient setting, so will some revision procedures. However, revisions are more complex and have greater impact physiologic stress on the patient. Therefore, the purposes of this study were to: (1) evaluate the number of patients discharged within 24 hours following revision; (2) compare the proportion of patients discharged following ball/liner exchange versus any component revision; and (3) determine the factors leading to successful discharge within 24 hours following revision THA (rTHA).

METHODS

There were 2,446 rTHA surgeries between 2017 and 2023 reviewed, of which 944 (38.6%) were included in the final analysis. There were 415 (44%) ball/liner exchanges and 529 (56%) component revisions. Septic revisions and patients who stayed in the hospital for > 72 hours were excluded. Patients were split into two cohorts: (1) those discharged within 24 hours; and (2) those who stayed in the hospital between 24 to 72 hours. Basic demographics and multiple perioperative factors were compared between cohorts.

RESULTS

There were 192 (20%) patients discharged within 24 hours following the rTHA, 126 (30.4%) following ball/liner exchange versus 66 (12.5%) following any component revision (P < 0.001). Medical complications that required intervention occurred in 179 (34%) patients undergoing ball/liner exchange compared to 270 (65%) patients undergoing any component revision (P < 0.01). There were no significant differences in patient comorbidities between cohorts, but patients undergoing any component revision were older, had greater estimated blood loss, more complications, and a longer time to physical therapy clearance, which was 29.6 hours in the ball/liner cohort compared to 39.1 hours in any component revision cohort (P < 0.0001).

CONCLUSIONS

Despite modern enhanced recovery protocols, discharge within 24 hours following aseptic rTHA remains uncommon. Medical complications requiring active management occurred in nearly 50% of patients. The strongest predictors of same-day discharge were time to achieving physical therapy milestones and the absence of perioperative complications.

Efficacy of an artificial intelligence preoperative planning system for assisting in revision surgery after artificial total hip arthroplasty

OBJECTIVE

To explore the early efficacy of an artificial intelligence preoperative planning system (AIHIP system) for assisting in hip revision surgery.

METHODS

The clinical data of 25 patients (26 hips) who underwent hip revision between June 2019 and December 2023 and who met the selection criteria were retrospectively analyzed. There were 13 males and 12 females; the ages ranged from 44 to 90 years, with a mean of 69.1 years. The patients' replacement of prosthesis model, operation time, hospitalization time, postoperative time out of bed, etc., as well as the occurrence of adverse events such as postoperative infection, fracture, and loosening of the prosthesis were recorded. The Harris Hip score (HHS) was used to evaluate the function of the affected limbs preoperatively, and 1 week and 6 months postoperatively, and hip mobility was compared preoperatively and 6 months postoperatively.

RESULTS

All 25 patients were followed up for 6 to 59 months, with an average of 25.3 months. Except for one patient who developed a thigh hematoma (treated with incision and drainage and decompression) and hip dislocation in one hip (repaired), the remaining patients experienced no adverse events such as loosening of the prosthesis or infection. The postoperative acetabular cup type matching degree completely matched 25 hips, not matching 1 hip (+ 2 number), for a matching rate of 96.15%; the femoral stem type matching degree completely matched 25 hips, generally matching 1 hip (-1 number), for a matching rate of 100%. The Harris scores were 54.7 ± 9.6 and 89.6 ± 7.0 at 1 week and 6 months after surgery, respectively, which were significantly improved (P < 0.05) compared with the preoperative scores of 33.5 ± 8.3, and further improved at 6 months after surgery compared with the 1-week period (P < 0.05). The patients' hip function was evaluated according to the Harris score at 6 months after surgery, and they were assigned to 23 good hips and 3 medium hips, which could satisfy daily life needs. Hip mobility at 6 months after surgery was 111.15 ± 9.72°, and the difference was statistically significant compared with the preoperative value of 79.42 ± 17.51° (t = -8.077, P < 0.001).

CONCLUSION

AIHIP system-assisted treatment of THA postoperative revision patients can improve the precision of revision surgery, and reduce the difficulty of surgery, in patients with good postoperative recovery and satisfactory early outcomes.

Complications and Survivorship After Aseptic Revision Total Hip Arthroplasty: Is There a Difference by Surgical Approach?

BACKGROUND

Revision total hip arthroplasty (rTHA) has traditionally been performed through the posterolateral approach (PA). Anterior approaches (AA) for rTHA are increasingly being utilized. The purpose of this study was to compare complications and survivorship from re-revision and reoperation after aseptic rTHA performed using an AA versus a PA.

METHODS

We retrospectively reviewed patients who underwent aseptic rTHA either through an AA (direct anterior approach [DAA], anterior-based muscle sparing [ABMS]) or PA from January 2017 to December 2021. There were 116 patients who underwent AA-rTHA (DAA 50, ABMS 66) or PA-rTHA (n = 105). Patient demographics, complications, and postoperative outcomes were collected.

RESULTS

The most common indication in both groups was aseptic loosening (n = 26, 22.4% AA, n = 28, 26.7% PA). Acetabular revision alone was most common in the AA group (n = 33, 28.4%), while both components were most commonly revised in the PA groups (n = 47, 44.8%). In all the AA-rTHA group, the index total hip arthroplasty was performed through a PA in 51% of patients, while the PA-rTHA group had the index procedure performed via AA in 4.8%. There was no statistically significant difference in re-revision rate between the DAA, ABMS, or PA groups (9.55 versus 5.3% versus 11.4%, respectively, P = .11). The most common overall reason for re-revision was persistent instability, with no difference in incidence of postoperative hip dislocation (n = 4, 6.8% DAA, n = 3, 5.3%, n = 10, 9.5% PA; P = .31).

CONCLUSIONS

This study demonstrates no difference in complication or re-revision survivorship after aseptic rTHA performed through a DAA, ABMS approach, or PA, nor between anterior or posterior-based approaches.

LEVEL OF EVIDENCE

Level III.

A systematic review on revision total hip arthroplasty employing the direct anterior approach

INTRODUCTION

The increased use of the direct anterior approach (DAA) for primary total hip arthroplasty (THA) has extended to revision THA. This systematic review evaluated studies reporting both the utility and clinical outcomes of revision THA using DAA, focusing on studies comparing revision approaches.

MATERIALS AND METHODS

A review of the Cochrane Library, EMBASE, and MEDLINE databases identified 577 publications. 538 were excluded after abstract screening. Full-text review identified 21 studies with 1627 patients. All studies were retrospective, level IV evidence. MINORS criteria rated 14 as poor and seven as moderate. Five studies compared DAA to alternative approaches. Meta-analysis was not performed due to significant heterogeneity and lack of comparative studies.

RESULTS

The most common indications for revision were aseptic loosening (n = 929) and polyethylene wear (n = 158). The majority of the studies (n = 11/21) performed primarily acetabular revision or head-liner exchanges. Half the revisions (50.6%; n = 823/1627) included femoral revisions (35.2%; n = 573/1627) or combined femoral-acetabular revisions (15.4%; n = 250/1627). However, 80.6% (n = 462/573) of femoral revisions were from two non-comparative studies. Among the five comparative studies, two included femoral or combined revisions with significantly more performed using the posterior approach. Three of the five comparative studies did not find the DAA protective against postoperative dislocation. The overall complication rate was 14.0%; periprosthetic femoral fracture (n = 106), dislocation (n = 80), and infection (n = 36) were most common. Fourteen studies reported patient-reported outcome measures, demonstrating consistent improvements following revision THA.

CONCLUSIONS

Current data on revision DAA THA are limited due to their retrospective nature. They demonstrate the ability to safely perform acetabular and head-liner revisions in carefully selected patients. Comparative studies lack femoral revisions, show a propensity for femoral fractures, and exhibit selection bias. Higher-quality, comparative prospective studies are needed.

TRIAL REGISTRATION

PROSPERO: CRD4202236457.

Is pre-operative block-test with lidocaine injection efficient in predicting the functional result of revision total hip arthroplasty?

BACKGROUND

While performing a hip joint aspiration for culture, a lidocaine diagnostic injection called block test can be performed during the investigation of painful total hip arthroplasties (THA). This test was formerly applied to limited series in pre-operative and without assessing the predictive value on the results of THA revision. Therefore we investigated a consecutive series of THA revisions who underwent pre-operative aspiration-block test to determine if patients with pre-operative positive block test (disappearance of symptoms) have a better clinical improvement after revision.

HYPOTHESIS

The positive pre-operative block test has a positive predictive value greater than 80% in predicting the favourable result of THA revisions.

MATERIALS AND METHODS

We reviewed 152 patients who had a hip aspiration associated with a block test before their THA revision. The patients were evaluated according to the Oxford hip score (OHS). The primary outcome was considered positive if the patient presented an improvement in the OHS greater than the Minimal Clinically Important Difference (MCID; 9 points) and/or if the postoperative OHS was higher than the Patient Acceptable Symptom State (PASS, defined as 39/48).

RESULTS

Block tests were positive for 61.2% (93/152) of patients. The median improvement in the OHS was 23.0 [IQR 16.0; 30.0] if the block test was positive versus 16.0 [IQR 4.0; 17.0] if negative (p = 0.002). The primary outcome after revision was strongly associated with block test positivity (p < 0.0001). The positive block test had a 67.7% sensitivity, 73.3% specificity, 91.4% Positive Predictive Value and 37.3% Negative Predictive Value for significant improvement after revision surgery.

CONCLUSION

Hip joint aspiration for culture with concomitant block test seems to be an interesting tool in predicting outcomes of revision surgery for painful THA.

LEVEL OF EVIDENCE

IV; retrospective study.

Revision Hip Arthroplasty Performed by Fellowship-Trained Versus Non-Fellowship-Trained Surgeons: A Comparison of Perioperative Management and Complications

BACKGROUND

Successful revision hip arthroplasty (rTHA) requires major resource allocation and a surgical team adept at managing these complex cases. The purpose of this study was to compare the results of rTHA performed by fellowship-trained and non-fellowship-trained surgeons.

METHODS

A national administrative database was utilized to identify 5,880 patients who underwent aseptic rTHA and 1,622 patients who underwent head-liner exchange for infection by fellowship-trained and non-fellowship-trained surgeons from 2010 to 2020 with a 5-year follow-up. Postoperative opioid and anticoagulant prescriptions were compared among surgeons. Patients treated by fellowship-trained and non-fellowship-trained surgeons had propensity scores matched based on age, sex, comorbidity index, and diagnosis. The 5-year surgical complications were compared using descriptive statistics. Multivariable analysis was performed to determine the odds of failure following head-liner exchange when performed by a fellowship-trained versus non-fellowship-trained surgeon.

RESULTS

Aseptic rTHA patients treated by fellowship-trained surgeons received fewer opioids (132 versus 165 milligram morphine equivalents per patient) and nonaspirin anticoagulants (21.4 versus 32.0%, P < .001). Fellowship-training was associated with lower dislocation rates (9.9 versus 14.2%, P = .011), fewer postoperative infections, and fewer periprosthetic fractures and re-revisions (15.2 versus 21.3%, P < .001). Head-liner exchange for infection performed by fellowship-trained surgeons was associated with lower odds of failure (31.2 versus 45.7%, odds ratio 0.76, 95% confidence interval 0.62 to 0.91, P < .001).

CONCLUSIONS

rTHA performed by adult reconstruction fellowship-trained surgeons results in fewer re-revisions in aseptic cases and head-liner exchanges. Variations in resources, volumes, and perioperative protocols may account for some of the differences.

Chronic Anticoagulation is Associated With Increased Risk for Postoperative Complications Following Aseptic Revision Total Hip Arthroplasty

BACKGROUND

With an aging global population, the incidence of revision total hip arthroplasty (rTHA) is expected to increase markedly. While patients undergoing primary total hip arthroplasty who require chronic anticoagulation (AC) have been associated with increased postoperative complications, less is known about the impact of chronic AC status on postoperative complications in the rTHA setting. This study sought to compare complication rates following aseptic rTHA between patients who were on chronic AC and those who were not.

METHODS

A large national database was utilized to retrospectively identify 9,421 patients who underwent aseptic rTHA between 2014 and 2019. Patients were divided into 2 cohorts: 1,790 patients (19.0%) were in the chronic AC cohort (ie, having an AC prescription filled within 6 months prior to and following rTHA), and 7,631 patients (81.0%) were not on chronic AC. Postoperative complications at 90-days and 2-years were compared between cohorts utilizing univariate and multivariate analyses, controlling for sex, age, and comorbidities.

RESULTS

At 90-days, chronic AC patients had increased odds of prosthetic joint infections (PJIs) (odds ratio [OR] 3.2, P < .001), surgical site infections (OR 3.6, P < .001), and mechanical prosthetic complications (OR 3.5, P < .001), which included any aseptic loosening, implant dislocation, or broken prosthetic. At 2-years, chronic AC patients had increased odds of PJI (OR 3.3, P < .001) as well as mechanical prosthetic complications (OR 3.2, P < .001). Chronic AC patients were also at increased risk for reoperation within 2 years after initial aseptic rTHA (OR 1.9, P < .001).

CONCLUSIONS

Patients on chronic AC have significantly higher odds of 90-day and 2-year complications after aseptic rTHA. This includes increased odds of PJI, surgical site infection, and mechanical prosthetic complications. Patients receiving chronic AC who undergo rTHA should be counseled on the risk-benefit ratio of their chronic AC status in a multidisciplinary setting to optimize their postoperative outcomes.

Performing Revision Arthroplasty Increases Surgeon and Practice Volumes Through the Generation of Subsequent Cases: A Retrospective Study

Background

Revision total knee (TKR) and hip (THR) arthroplasty surgeries are disincentivized due to unfavorable reimbursement rates, surgical times, and complication rates. Our study investigates secondary benefits of performing these surgeries by generating subsequent cases for surgeons and practices.

Methods

Patients undergoing TKR and THR between April 1, 2011, and January 1, 2019, at our tertiary academic institution were analyzed. Patients were identified with Current Procedural Terminology codes for TKR and THR. We calculated a subsequent surgery rate on the same or different joint by the initial surgeon or another surgeon within the practice to determine the procedure yield after initial revision arthroplasty.

Results

One thousand six hundred twenty-five patients met inclusion criteria. Six hundred forty-nine (39.9%) patients received at least one subsequent procedure on any joint by any orthopaedic surgeon in the practice. Four hundred five patients (24.9%) underwent another procedure on any joint by the same surgeon. Two hundred sixty patients (16.0%) underwent another procedure on the same joint by the same surgeon, with 109 cases (41.9%) being a planned second stage of a 2-stage revision for infection. Two hundred eighty-five patients (17.5%) underwent another procedure on a different joint by the same surgeon, with 122 of these patients (42.8%) undergoing at least one primary total hip or knee arthroplasty.

Conclusions

TKRs and THRs can increase surgeon and practice volumes through the generation of future cases, which are primarily the second stage of a 2-stage revision or primary joint arthroplasties on other joints.

Reversal of the Halo Effect: Prolonged Participation in Comprehensive Care for Joint Replacement Negatively Impacts Revision Metrics

Background

The downstream regional effect of the Comprehensive Care for Joint Replacement (CJR) program on care pathway-adjacent patients, including revision arthroplasty patients, is poorly understood. Prior studies have demonstrated that care pathways targeting primary total joint arthroplasty may produce a halo effect, impacting more complex patients with parallel care pathways. However, neither the effect of regional referral changes from CJR nor the durability of these positive changes with prolonged bundle participation has been assessed.

Methods

Blinded data were pulled from electronic medical records. Primary analyses focused on the effect of CJR participation from 2015 (baseline) to 2020 (final participation year) at a tertiary care safety-net hospital. Patient demographics were evaluated using multivariate analysis of variance and chi-square calculations between procedure types over time.

Results

Patients who underwent revision total knee arthroplasty (N = 376) and revision total hip arthroplasty (N = 482) were included. More patients moved through the revision-care pathway over the participation period, with volume increasing by 42% over time. Patients became more medically complex: the Charlson comorbidity index increased from 3.91 to 4.65 (P = .01). The mean length of stay decreased from 5.14 days to 4.50 days (P = .03), but the all-cause complication (8.3%-15.2%; P = .02) and readmission rates (13.6%-16.6%; P = .19) increased over time.

Conclusions

Despite care pathway improvements over 5 years of CJR participation, revision patients did not display clear benefits in quality metrics but demonstrated a considerable increase in volume and medical complexity over time. The care of these patients may supersede even thoughtfully implemented care pathways, especially when referral burden increases, as may be prone to happen in regional, financial risk-conferring value-based programs. Understanding the impact of mandatory bundled payment programs like CJR on the care of arthroplasty patients regionally will be essential as value-based programs evolve.

Cement loaded with high-dose gentamicin and clindamycin does not reduce the risk of subsequent infection after aseptic total hip or knee revision arthroplasty: a preliminary study

PURPOSE

The aim of this study was to quantify the prophylactic effect of high-dose gentamicin and clindamycin antibiotic-loaded bone cement (ALBC) during revision total hip (rTHA) or knee (rTKA) arthroplasty for aseptic reasons. The hypothesis was that the raw surgical site infection (SSI) rate is lower when this particular cement is used in comparison with cement loaded with standard-dose gentamicin during rTHA or rTKA for aseptic reasons.

METHODS

This retrospective study included 290 consecutive patients undergoing aseptic rTHA or rTKA. Two consecutive cohorts were defined: the first (control group) involved 145 patients where ALBC with gentamicin only was used; the second (study group) involved 145 patients where ALBC with high-dose gentamicin and clindamycin was used. The primary endpoint was the raw SSI rate after 24 months.

RESULTS

The raw SSI rate was 8/145 (6%) in the control group and 13/145 (9%) in the study group (odds ratio 0.62, p = 0.26). There was a significant impact of the presence of any risk factor on the SSI rate (15/100 versus 6/169, odds ratio = 4.25, p = 0.002), but no significant impact of any individual risk factor. No complication or side effect related to ALBC was observed in either group.

CONCLUSION

These results do not support the routine use of gentamicin and clindamycin ALBC for fixation of revision implants after rTHA and rTKA for aseptic reasons.

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.

Specimen-specific finite element representations of implanted hip capsules

The hip capsule is a ligamentous structure that contributes to hip stability. This article developed specimen-specific finite element models that replicated internal-external (I-E) laxity for ten implanted hip capsules. Capsule properties were calibrated to minimize root mean square error (RMSE) between model and experimental torques. RMSE across specimens was 1.02 ± 0.21 Nm for I-E laxity and 0.78 ± 0.33 Nm and 1.10 ± 0.48 Nm during anterior and posterior dislocation, respectively. RMSE for the same models with average capsule properties was 2.39 ± 0.68 Nm. Specimen-specific models demonstrated the importance of capsule tensioning in hip stability and have relevance for surgical planning and evaluation of implant designs.

Revision of total hip arthroplasty by long locking stem with fully hydroxyapatite-coated modular metaphysis (Reef™): A continuous series of 78 cases at a minimum 2-year follow-up

INTRODUCTION

Since the Wagner and Vives stems were introduced in the 1980s, the range of uncemented implants for femoral revision has grown with increasing demand. Cementless modular implants with a wide range of lengths and diameters improved adaptation to the bone and secondary metaphyseal integration. Data are sparse for the Reef™ locking stem (Depuy-Synthes, Saint-Priest, France) and we therefore conducted a retrospective study at more than 2 years' follow-up, in a continuous series of total hip arthroplasty (THR) revision procedures using this long fully-hydroxyapatite-coated modular locking stem, assessing (1) implant survival, (2) clinical and functional results, and (3) radiographic results.

HYPOTHESIS

The study hypothesis was that all-cause≥2-year survival is>90%.

PATIENTS AND METHODS

Between 2007 and 2018, 413 femoral stem exchanges were performed in our center, a Reef™ model being needed in 93 cases. Etiologies comprised: Vancouver B2 or B3 periprosthetic fracture (57%, n=53), aseptic loosening (33%, n=30), septic loosening (10%, n=9) and 1 case of aseptic non-union under the stem (1%, n=1). Clinical and functional assessment used Harris Hip Score (HHS), Postel Merle d'Aubigné score (PMA) and Oxford-12 Hip Score (OHS). Radiographic assessment used immediate postoperative views and last follow-up radiographs, assessing osseointegration, filling index and stress shielding. Implant survival was estimated following Kaplan-Meier with 95% confidence intervals.

RESULTS

Mean follow-up was 6±3 years (range, 2-12). Last follow-up included 78 cases for analysis (12 deaths [13%] and 3 patients lost to follow-up before 2 years [3%]). Ten-year Reef™ implant survival was 98.7% (95% CI: 96.3-100) free of aseptic loosening (n=1) and 94% (95% CI: 87-100) for all causes (n=3). The failures related to aseptic loosening involved femoral stem fracture away from the modular part; the 2 cases of septic loosening did not undergo reimplantation for medical reasons. Preoperatively (scheduled surgeries, excluding periprosthetic fractures: n=40), mean HHS was 43±12 and 77±12 at last follow-up (81±13 in scheduled surgery [n=40] and 73±11 in emergency surgery for periprosthetic fracture [n=53]), mean PMA score was 13±2 and mean OHS was 26±9. The infection rate was 11% (n=9) including 7.6% new infection (n=6). The dislocation rate was 6% (n=5). The radiographic stress shielding rate was 11% (n=9) and significantly associated with low metaphyseal filling index (76±7% vs. 83±8% [p=0.009]).

DISCUSSION

Like other recent data, the present good survival results support the trend for uncemented stems in femoral revision, as encouraged by the 1999 symposium of the French Society of Orthopedic Surgery and Traumatology (SoFCOT). Primary diaphyseal fixation enables secondary metaphyseal integration on an implant with modularity ensuring good bone adaptation. Close contact between the bone and hydroxyapatite surfaces is a key-point in the surgical strategy.

LEVEL OF EVIDENCE

IV, retrospective study.

Antibiotic prophylaxis before tissue biopsy has no effect on culture results in presumed aseptic revision total hip arthroplasty

Background: Antibiotic prophylaxis (AP) is considered to be the gold standard for revision total hip arthroplasty (R-THA) due to the high incidence of prosthetic joint infection (PJI). To diagnose PJI, intraoperative tissue biopsies for culture are of particular importance. However, antibiotic interference could theoretically lead to less reliable culture results. Currently, there is no consensus on whether AP should be administered before or after tissue biopsy. In this study, we aimed to investigate the effect of AP timing on culture results and PJI rates in presumed aseptic R-THA. Methods: A retrospective single-center cohort study among 490 patients was performed; 61 patients received AP pre-incision, and 429 patients received AP post-biopsy. At least three intraoperative tissues were sampled for each patient and cultured for a minimum of 2 weeks. Minimum follow-up was 6 months. Epidemiological and clinical data (including culture results and incidence of PJI during follow-up) were gathered and analyzed. Results: Positive (4.9 % vs. 5.4 %, p = 0.89 ) and contaminated culture results (23.0 % vs. 22.6 %, p = 0.95 ) were not significantly different between pre-incisional and post-biopsy AP administration. Post-operative PJI incidence during follow-up was 1.6 % and 3.0 %, respectively. This difference was not statistically significant (p = 0.54 ). Conclusion: Pre-incisional AP administration does not yield fewer culture results compared to post-biopsy AP administration. Although statistically not significant, PJI during follow-up was almost twice as high when AP was withheld until after tissue biopsy. Other literature also supports the additional protective benefit of pre-incisional AP. Therefore, we believe pre-incisional AP administration is preferable for presumed aseptic R-THA.

A modified frailty index predicts complication, readmission, and 30-day mortality following the revision total hip arthroplasty

INTRODUCTION

This study aimed to develop a modified frailty index (MFI) to predict the risks of revision total hip arthroplasty (THA).

METHODS

Data from the American College of Surgeons - National Surgical Quality Improvement Program were analyzed for patients who underwent revision THA from 2015 to 2020. An MFI was composed of the risk factors, including severe obesity (body mass index > 35), osteoporosis, non-independent function status prior to surgery, congestive heart failure within 30 days of surgery, hypoalbuminemia (serum albumin < 3.5), hypertension requiring medication, type 1 or type 2 diabetes, and a history of chronic obstructive pulmonary disease or pneumonia. The patients were assigned based on the MFI scores (MFI0, no risk factor; MFI1, 1-2 risk factors; MFI2, 3-4 risk factors; and MFI3, 5+ risk factors). Confidence intervals were set at 95% with a P value less than or equal to 0.05 considered statistically significant.

RESULTS

A total of 17,868 patients (45% male, 55% female) were included and had an average age of 68.5 ± 11.5 years. Odds of any complication, when compared to MFI0, were 1.4 (95% CI [1.3, 1.6]) times greater for MFI1, 3.2 (95% CI [2.8, 3.6]) times greater for MFI2, and 10.8 (95% CI [5.8, 20.0]) times greater for MFI3 (P < 0.001). Odds of readmission, when compared to MFI0, were 1.4 (95% CI [1.3, 1.7]) times greater for MFI1, 2.5 (95% CI [2.1, 3.0]) times greater for MFI2, and 4.1 (95% CI [2.2, 7.8]) times greater for MFI3 (P < 0.001).

CONCLUSION

Increasing MFI scores correlate with increased odds of complication and readmission in patients who have undergone revision THA. This MFI may be used to predict the risks after revision THA.

Does Using Highly Porous Tantalum in Revision Total Hip Arthroplasty Reduce the Rate of Periprosthetic Joint Infection? A Systematic Review and Meta-Analysis

BACKGROUND

Studies suggest tantalum (Ta) implants may have inherent antibacterial properties. However, there is no consensus regarding the effectiveness of Ta in preventing periprosthetic joint infection (PJI) after revision total hip arthroplasty (rTHA).

METHODS

We searched 5 main databases for articles reporting the rate of PJI following rTHA using Ta implants from inception to February 2022. The PJI rates of the Ta group were meta-analyzed, compared with the control group, and represented as relative risks (RRs) in forest plots.

RESULTS

We identified 67 eligible studies (28,414 joints) for assessing the prevalence of PJI following rTHA using Ta implants. Among these studies, only 9 compared the Ta implant group with a control group. The overall PJI rate following rTHA using Ta implants was 2.9% (95% confidence interval [CI]: 2.2%-3.8%), while it was 5.7% (95% CI = 4.1%-7.8%) if only septic revisions were considered. Comparing the Ta and control groups showed a significantly lower PJI rate following all-cause rTHA with an RR = 0.80 (95% CI = 0.65-0.98, P < .05). There was a trend toward lower reinfection rates in the Ta group after rTHA in septic cases, although the difference was not statistically significant (RR = 0.75, 95% CI = 0.44-1.29, P = .30).

CONCLUSIONS

Ta implants are associated with a lower PJI rate following all-cause rTHA but not after septic causes. Despite positive results, the clinical significance of Ta still remains unclear since the PJI rate was only reduced by 20%.

LEVEL OF EVIDENCE

IV.

The Safety and Efficacy of Microporous Polysaccharide Hemospheres in Terms of the Complication Rates in Total Hip Arthroplasty for Femoral Neck Fractures: A Control-Matched Retrospective Cohort

AIMS

This study aimed to assess the safety and efficacy of microporous polysaccharide hemospheres (MPSHs) in managing blood loss and reducing the risk of postoperative haematoma and early periprosthetic joint infection (PJI) following total hip arthroplasty (THA) for femoral neck fracture (FNF), in the context of the existing treatment challenges.

METHODS

A control-matched retrospective analysis of 163 patients undergoing unilateral primary THA for displaced FNF between 2020 and 2023 was performed. The study group consisted of 74 patients who received MPSH administered intraoperatively. The control group consisted of 89 patients who received no topical haemostatics. One-to-one case-control matching between groups was performed. The primary outcome was a perioperative change in the haematologic values (haemoglobin, red blood cell count, haematocrit, platelet concentration) and transfusion rate. The secondary outcomes were the incidence of postoperative local haematoma formation, prolonged wound secretion, surgical site infection (SSI), and PJI within 3 months of surgery.

RESULTS

Our analysis found no statistically significant differences in the haematologic parameters between the control and study cohorts. The changes in the haemoglobin concentration were not significant between the control group (3.18 ± 1.0 g/dL) and the treatment group (2.87 ± 1.15 g/dL) (p = 0.3). There were no significant differences (p = 0.24) in the haematocrit and red blood cell concentration (p = 0.15). The platelet levels did not significantly differ (p = 0.12) between the groups. Additionally, we found no significant discrepancy in the incidence of early PJI or blood transfusion rates between the groups. No adverse effects following MPSH use were recorded in the study group.

CONCLUSIONS

Routine use of MPSH in THA for FNF management appears to be safe, with no observed adverse events related to Arista® use. Although there was a tendency towards reduced blood loss in the Arista® AH group, MPSH did not significantly impact bleeding complications, local haematoma formation, or subsequent PJI.

Update on post-traumatic periprosthetic acetabular fractures

Aims

Post-traumatic periprosthetic acetabular fractures are rare but serious. Few studies carried out on small cohorts have reported them in the literature. The aim of this work is to describe the specific characteristics of post-traumatic periprosthetic acetabular fractures, and the outcome of their surgical treatment in terms of function and complications.

Methods

Patients with this type of fracture were identified retrospectively over a period of six years (January 2016 to December 2021). The following data were collected: demographic characteristics, date of insertion of the prosthesis, details of the intervention, date of the trauma, characteristics of the fracture, and type of treatment. Functional results were assessed with the Harris Hip Score (HHS). Data concerning complications of treatment were collected.

Results

Our series included 20 patients, with a mean age of 77 years (46 to 90). All the patients had at least one comorbid condition. Radiographs showed that 75% of the fractures were pure transverse fractures, and a transverse component was present in 90% of patients. All our patients underwent surgical treatment: open reduction and internal fixation, revision of the acetabular component, or both. Mean follow-up was 24 months, and HHS at last follow-up was 75.5 (42 to 95). The principal complications observed were dislocations of the prosthesis (30%) and infections (20%). A need for revision surgery was noted in 30% of patients. No dislocation occurred in patients undergoing osteosynthesis with acetabular reconstruction. We did not note either mechanical loosening of the acetabular component nor thromboembolic complications. In all, 30% of patients presented acute anemia requiring transfusion, and one death was reported.

Conclusion

Post-traumatic periprosthetic acetabular fractures frequently have a transverse component that can destabilize the acetabular implant. The frequency of complications, principally dislocations, led to a high rate of revision surgery. Improvements in preoperative planning should make it possible to codify management to reduce this high rate of complications. The best results were obtained when the surgical strategy combined osteosynthesis with acetabular reconstruction.

Patient mortality after total hip arthroplasty revision surgery

Background

Complications following revision total hip arthroplasty can cause significant morbidity and have a high mortality rate. Patient age and American Society of Anaesthesiologists (ASA) physical status classification system score are important determinants of mortality following revision hip arthroplasty. There is a paucity of high-quality evidence assessing the risk of mortality following revision hip arthroplasty stratified by indications of surgery. The aim of this study is to compare survival of patients undergoing revision THA for different indications.

Methods

This retrospective case series reviewed the mortality rate following revision hip surgery performed by a single surgeon between 2009 and 2016 with a minimum 2 year follow up. Kaplan Meir analysis was performed using mortality as the end point. Log rank testing was used to determine if the indication for surgery conferred a difference in survival.

Results

One hundred and ninety-eight consecutive cases were done using a tapered modular uncemented stem in 183 patients and were followed up for a mean period of 51.8 months (range, 24-121). Sixty patients died (67 % survivorship) during the follow up period with a 5-year survival rate of 78 %. Revision surgery performed for aseptic loosening had the best survival and hemiarthroplasty had the worst and differences in survival were statistically significant (P = 0.000002).

Conclusion

The indication for revision surgery is an important criterion which must be given weightage along with age, functional status of patient and ASA physical status score while planning revision surgery and counselling patients.

Micromotion and stress shielding between taper fluted and cylindrical femoral stems for Paprosky bone deficiency type IIIB

PURPOSE

Taper fluted and cylindrical femoral stems have been commonly used for revision surgery with femoral bone loss. Shape and material differences between taper fluted and cylindrical confused surgeons whether superiority and inferiority in comparisons especially for type IIIB Paprosky bone deficiency. This study aims to investigate the micromotion between implant and bone interface and stress distribution around the implant in human cadaveric experiments.

METHODS

Paired comparisons of 7 cadavers between taper fluted stem and cylindrical stem were tested under dynamic cyclic loading.

RESULTS

The results showed appropriate bone-implant micromotions for bone osteointegration could be observed between both taper fluted and cylindrical stems (85 ± 10 μm and 113 ± 80 μm respectively, p = 0.59). Taper fluted stem attained the load distribution from the proximal to distal surrounding bone (from 4.92 ± 2.87 MPa to 2.14 ± 1.43 MPa, p = 0.43), while the cylindrical stem type showed the proximal bone stress shielding (from 2.56 ± 0.76 MPa to 5.23 ± 0.77 MPa, p = 0.03).

CONCLUSION

Both taper fluted and cylindrical femoral stems provided an adequate initial stability with a proper micromotions for bone-implant osteointegration for type IIIB Paprosky femoral bone loss. The taper fluted femoral stem had better biomechanical advantage in terms of greater stress transfer to periprosthetic bone.

Efficacy and safety of postoperative single-dose anticoagulant treatment in preventing venous thromboembolism after revision hip arthroplasty: a retrospective cohort study

PURPOSE

The purpose of the study is to determine the efficacy and safety of postoperative single-dose anticoagulant treatment in preventing venous thromboembolism (VTE) after revision THA, in comparison with a multiple-dose chemoprophylaxis protocol.

METHODS

We retrospectively compared 295 patients undergoing revision THA who received multiple-dose chemoprophylaxis protocol (40 mg low-molecular-weight heparin once and oral rivaroxaban for 10 days) or single-dose chemoprophylaxis protocol (40 mg low-molecular-weight heparin once) for VTE. The patients in both groups performed active lower limb exercises. Each group was further stratified into subgroups based on the aetiology of revision. The incidence of VTE, wound complications within three months, hidden blood loss (HBL), transfusion rate, and surgical drainage duration were recorded.

RESULTS

The incidence rates of VTE (P = 0.870) did not differ between the two prophylaxis protocols. However, significant differences were observed in wound complications within three months (P = 0.002), HBL (P = 0.015), transfusion rate (P = 0.028). Surgical drainage duration was also shorter in the single-dose chemoprophylaxis group (P = 0.0023). In the subgroup analysis, the use of single-dose chemoprophylaxis protocol cannot significantly reduce HBL and transfusion rate after septic revision THA. The use of multiple-dose chemoprophylaxis protocol (OR = 2.89, P = 0.002) and high BMI (OR = 1.09, P = 0.037) were independent risk factors of wound complications.

CONCLUSIONS

Single-dose chemoprophylaxis protocol effectively and safely prevented VTE after revision THA compared with multiple-dose chemoprophylaxis protocol. The effect in reducing HBL and postoperative transfusion rate was limited in septic revision.

Defining Clinically Meaningful Subgroups for Risk Stratification in Patients Undergoing Revision Total Hip Arthroplasty: A Combined Unsupervised and Supervised Machine Learning Approach

BACKGROUND

Studies developing predictive models from large datasets to risk-stratify patients under going revision total hip arthroplasties (rTHAs) are limited. We used machine learning (ML) to stratify patients undergoing rTHA into risk-based subgroups.

METHODS

We retrospectively identified 7,425 patients who underwent rTHA from a national database. An unsupervised random forest algorithm was used to partition patients into high-risk and low-risk strata based on similarities in rates of mortality, reoperation, and 25 other postoperative complications. A risk calculator was produced using a supervised ML algorithm to identify high-risk patients based on preoperative parameters.

RESULTS

There were 3,135 and 4,290 patients identified in the high-risk and low-risk subgroups, respectively. Each group significantly differed by rate of 30-day mortalities, unplanned reoperations/readmissions, routine discharges, and hospital lengths of stay (P < .05). An Extreme Gradient Boosting algorithm identified preoperative platelets < 200, hematocrit > 35 or < 20, increasing age, albumin < 3, international normalized ratio > 2, body mass index > 35, American Society of Anesthesia class ≥ 3, blood urea nitrogen > 50 or < 30, creatinine > 1.5, diagnosis of hypertension or coagulopathy, and revision for periprosthetic fracture and infection as predictors of high risk.

CONCLUSION

Clinically meaningful risk strata in patients undergoing rTHA were identified using an ML clustering approach. Preoperative labs, demographics, and surgical indications have the greatest impact on differentiating high versus low risk.

LEVEL OF EVIDENCE

III.

Case report and review: Angiosarcoma with thrombocytopenia after total hip arthroplasty

Total hip arthroplasty (THA) is a common treatment for osteoarthritis and is also performed for other conditions, such as secondary arthritis due to developmental dysplasia of the hip. Various THA types may be complicated by osteolysis and an inflammatory pseudotumor due to an adverse reaction to metal debris. Rarely, THA has been associated with malignant tumors, but their causality remains unclear. In this case report, we describe a female patient with developmental dysplasia of the hip. She had undergone left metal-on-polyethylene THA, acetabular revision of the THA, and left total knee arthroplasty. In addition, she had a history of dyslipidemia and telangiectasia of the eyes, anemia, hiatal hernia, and pleuritis. A THA-associated mass (suspected to be a pseudotumor) had been detected during a previous hospital admission due to pleuritis. She was hospitalized due to swelling in her left lower limb, fatigue, and bruises. A clinical examination revealed anemia, thrombocytopenia, and growth of the suspected pseudotumor. Within 6 weeks, she presented with bleeding of the oral mucosa, hemoptysis, melena, severe thrombocytopenia that did not respond to treatment, elevated D-dimer and C-reactive protein levels, severe pain, increased osteolysis, and fractures around the THA. Infection or malignancy was suspected, but two trocar biopsies suggested an inflammatory pseudotumor. Since her anemia and thrombocytopenia were considered to have been caused by an inflammatory process within the suspected pseudotumor, her suspected pseudotumor and all THA components were surgically removed. However, she developed severe alveolar hemorrhaging and hypoxia and died 2 weeks after her surgery. Histopathological analysis of her surgical and autopsy samples revealed highly malignant angiosarcoma. Although individual cases of malignancies associated with THA have been reported, the literature lacks a clear association between THA and increased cancer risk. Most pseudotumors are non-malignant. The patient's case presented in this report exemplifies the challenges to the differential diagnosis of a THA-associated pseudotumor and rare angiosarcoma. Atypically rapid tumor growth, severe osteolysis, and deterioration in the general wellbeing suggest a malignant disease.

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.

Incidence and Risk Factors for Fracture-Related Infection After Peri-Prosthetic Femoral Fractures: A Multicenter Retrospective Study (TRON Group Study)

Background: Fracture-related infection (FRI) sometimes occurs with peri-prosthetic femoral fracture (PPF) treatment. Fracture-related infection often leads to multiple re-operations, possible non-union, a decreased clinical function, and long-term antibiotic treatment. In this multicenter study, we aimed to clarify the incidence of FRI, the causative organisms of wound infection, and the risk factors associated with post-operative infection for PPF. Patients and Methods: Among 197 patients diagnosed with peri-prosthetic femoral fracture who received surgical treatment in 11 institutions (named the TRON group) from 2010 to 2019, 163 patients were included as subjects. Thirty-four patients were excluded because of insufficient follow-up (less than six months) or data loss. We extracted the following risk factors for FRI: gender, body mass index, smoking history, diabetes mellitus, chronic hepatitis, rheumatoid arthritis, dialysis, history of osteoporosis treatment, injury mechanism (high- or low-energy), Vancouver type, and operative information (waiting period for surgery, operation time, amount of blood loss, and surgical procedure). We conducted a logistic regression analysis to investigate the risk factors for FRI using these extracted items as explanatory variables and the presence or absence of FRI as the response variable. Results: Fracture-related infection occurred after surgery for PPF in 12 of 163 patients (7.3%). The most common causative organism was Staphylococcus aureus (n = 7). The univariable analysis showed differences for dialysis (p = 0.001), Vancouver type (p = 0.036), blood loss during surgery (p = 0.001), and operative time (p = 0.001). The multivariable logistic-regression analysis revealed that the patient background factor of dialysis (odds ratio [OR], 22.9; p = 0.0005), and the operative factor of Vancouver type A fracture (OR, 0.039-1.18; p = 0.018-0.19) were risk factors for FRI. Conclusions: The rate of post-operative wound infection in patients with a PPF was 7.3%. Staphylococcus was the most frequent causative organism. The surgeon should pay attention to infection after surgery for patients with Vancouver type A fractures and those undergoing dialysis.

Inflammatory, Oxidative Stress and Small Cellular Particle Response in HUVEC Induced by Debris from Endoprosthesis Processing

We studied inflammatory and oxidative stress-related parameters and cytotoxic response of human umbilical vein endothelial cells (HUVEC) to a 24 h treatment with milled particles simulating debris involved in sandblasting of orthopedic implants (OI). We used different abrasives (corundum-(Al₂O₃), used corundum retrieved from removed OI (u. Al₂O₃), and zirconia/silica composite (ZrO₂/SiO₂)). Morphological changes were observed by scanning electron microscopy (SEM). Concentration of Interleukins IL-6 and IL-1β and Tumor Necrosis Factor α (TNF)-α was assessed by enzyme-linked immunosorbent assay (ELISA). Activity of Cholinesterase (ChE) and Glutathione S-transferase (GST) was measured by spectrophotometry. Reactive oxygen species (ROS), lipid droplets (LD) and apoptosis were measured by flow cytometry (FCM). Detachment of the cells from glass and budding of the cell membrane did not differ in the treated and untreated control cells. Increased concentration of IL-1β and of IL-6 was found after treatment with all tested particle types, indicating inflammatory response of the treated cells. Increased ChE activity was found after treatment with u. Al₂O₃ and ZrO₂/SiO₂. Increased GST activity was found after treatment with ZrO₂/SiO₂. Increased LD quantity but not ROS quantity was found after treatment with u. Al₂O₃. No cytotoxicity was detected after treatment with u. Al₂O₃. The tested materials in concentrations added to in vitro cell lines were found non-toxic but bioactive and therefore prone to induce a response of the human body to OI.

Dislocation and survival rate of dual mobility cups in revision total hip arthroplasty in patients with high risk of instability

PURPOSE

Instability remains as an unsolved complication after revision total hip arthroplasty (rTHA). Dual mobility (DM) cups have decreased dislocation rate in rTHA; however, there are few clinical studies that evaluate the risk of dislocation after rTHA in patients with high risk of instability.

METHODS

Between 2007 and 2019, 95 consecutive rTHA using a DM cup, in 93 patients with instability risk factors were retrospectively reviewed. Instability risk factors were defined as follows: deficient abductor mechanism (22.1%), previous dislocation (68.4%), Paprosky 3 acetabular bone defect (21.1%), neuromuscular disease (4.2%), lumbar spine arthrodesis (6.3%), and more than one previous surgery (33.6%). Mean follow-up was 4.3 ± 2.4 years. Clinical and radiographic parameters were reported. DM cup survival was determined using a Kaplan-Meier analysis with re-revision for any cause as the end-point. Surgical complications and re-dislocation rate was recorded.

RESULTS

Seven DM cups were re-revised; three due to aseptic loosening, three due to peri-prosthetic joint infection (PJI), and one due to instability. At seven years follow-up, the survival rate of the DM cup using re-revision for any reason as the end-point was 82.4% (95% confidence interval, 66.4-98.4%). There were 12 (12.6%) complications: two (2.1%) dislocations, six (6.3%) PJI, four (4.2%) peri-prosthetic fractures.

CONCLUSION

Our findings suggest DM cups are effective reducing dislocation rate in rTHA in patients with a high risk of instability, without increasing early aseptic loosening and with a low rate of dislocation. Nevertheless, longer follow-up is needed to confirm implant stability and dislocation rates in the long term.

Development and internal validation of machine learning algorithms for predicting complications after primary total hip arthroplasty

INTRODUCTION

Complications after total hip arthroplasty (THA) may result in readmission or reoperation and impose a significant cost on the healthcare system. Understanding which patients are at-risk for complications can potentially allow for targeted interventions to decrease complication rates through pursuing preoperative health optimization. The purpose of the current was to develop and internally validate machine learning (ML) algorithms capable of performing patient-specific predictions of all-cause complications within two years of primary THA.

METHODS

This was a retrospective case-control study of clinical registry data from 616 primary THA patients from one large academic and two community hospitals. The primary outcome was all-cause complications at a minimum of 2-years after primary THA. Recursive feature elimination was applied to identify preoperative variables with the greatest predictive value. Five ML algorithms were developed on the training set using tenfold cross-validation and internally validated on the independent testing set of patients. Algorithms were assessed by discrimination, calibration, Brier score, and decision curve analysis to quantify performance.

RESULTS

The observed complication rate was 16.6%. The stochastic gradient boosting model achieved the best performance with an AUC = 0.88, calibration intercept = 0.1, calibration slope = 1.22, and Brier score = 0.09. The most important factors for predicting complications were age, drug allergies, prior hip surgery, smoking, and opioid use. Individual patient-level explanations were provided for the algorithm predictions and incorporated into an open access digital application: https://sorg-apps.shinyapps.io/tha_complication/ CONCLUSIONS: The stochastic boosting gradient algorithm demonstrated good discriminatory capacity for identifying patients at high-risk of experiencing a postoperative complication and proof-of-concept for creating office-based applications from ML that can perform real-time prediction. However, this clinical utility of the current algorithm is unknown and definitions of complications broad. Further investigation on larger data sets and rigorous external validation is necessary prior to the assessment of clinical utility with respect to risk-stratification of patients undergoing primary THA.

LEVEL OF EVIDENCE

III, therapeutic study.

Acetabular Wall Weakening in Total Hip Arthroplasty: A Pilot Study

Total hip arthroplasty is a widely performed operation allowing disabled patients to improve their quality of life to a degree greater than any other elective procedure. Planning for a THA requires adequate patient assessment and preoperative characterizations of acetabular bone loss via radiographs and specific classification schemes. Some surgeons may be inclined to ream at a larger diameter thinking it would lead to a more stable press-fit, but this could be detrimental to the acetabular wall, leading to intraoperative fracture. In the attempt to reduce the incidence of intraoperative fractures, the current study aims to identify how increased reaming diameter degrades and weakens the acetabular rim strength. We hypothesized that there is proportionality between the reaming diameter and the reduction in acetabular strength. To test this hypothesis, this study used bone surrogates, templated from CT scans, and reamed at different diameters. The obtained bone surrogate models were then tested using an Intron 8874 mechanical testing machine (Instron, Norwood, MA) equipped with a custom-made fixture. Analysis of variance (ANOVA) was used to identify differences among reamed diameters while linear regression was used to identify the relationship between reamed diameters and acetabular strength. We found a moderate correlation between increasing reaming diameter that induced thinning of the acetabular wall and radial load damage. For the simplified acetabular model used in this study, it supported our hypothesis and is a promising first attempt in providing quantitative data for acetabular weakening induced by reaming.

Combination d-Amino Acid and Photothermal Hydrogel for the Treatment of Prosthetic Joint Infections

Prosthetic joint infection (PJI) is a devastating complication requiring surgical intervention and prolonged antimicrobial treatment. The prevalence of PJI is on the rise, with an average incidence of 60,000 cases per year and a projected annual cost of $1.85 billion in the US. The underlying pathogenesis of PJI involves the formation of bacterial biofilms that protect the pathogen from the host immune response and antibiotics, making it difficult to eradicate such infections. Biofilms on implants are also resistant to mechanical brushing/scrubbing methods of removal. Since the removal of biofilms is currently only achievable by the replacement of the prosthesis, therapies aimed at eradicating biofilms while enabling retention of implants will revolutionize the management of PJIs. To address severe complications associated with biofilm-related infections on implants, we have developed a combination treatment that is based on a hydrogel nanocomposite system, containing d-amino acids (d-AAs) and gold nanorods, which can be delivered and transforms from a solution to a gel state at physiological temperature for sustained release of d-AAs and light-activated thermal treatment of infected sites. Using this two-step approach to utilize a near-infrared light-activated hydrogel nanocomposite system for thermal treatment, following initial disruption with d-AAs, we were able to successfully demonstrate in vitro the total eradication of mature Staphylococcus aureus biofilms grown on three-dimensional printed Ti-6Al-4V alloy implants. Using a combination of cell assays, computer-aided scanning electron microscopy analyses, and confocal microscopy imaging of the biofilm matrix, we could show 100% eradication of the biofilms using our combination treatment. In contrast, we were only able to see 25% eradication of the biofilms using the debridement, antibiotics, and implant retention method. Moreover, our hydrogel nanocomposite-based treatment approach is adaptable in the clinical setting and capable of combating chronic infections brought about by biofilms on medical implants.

Hepatitis C Is Associated With Higher Short-Term Complication Rates After Initial Aseptic and Septic Revision Total Hip Arthroplasty: A Matched Cohort Study

BACKGROUND

It is unclear if hepatitis C virus (HCV) negatively impacts outcomes of revision total hip arthroplasty (rTHA). The purpose of this study is to trend recent rTHA utilization in patients who have HCV and compare postoperative complication rates versus a matched cohort.

METHODS

All patients who underwent rTHA were retrospectively identified in a national database. Patients who had HCV (n = 1,746) were matched 1:3 with a matching group (n = 5,238) for age, gender, and several comorbidities. Cochran-Armitage tests were used to analyze trends in the annual proportion of rTHA performed in patients who had HCV from 2010 to 2019. Rates of 90-day medical and prosthesis-related complications within 2 years postoperatively were compared with multivariable logistic regressions.

RESULTS

The annual proportion of rTHA performed in patients who had HCV significantly increased from 2010 to 2019 (P < .001). Patients who had HCV exhibited significantly higher rates of acute kidney injuries (7.6% versus 4.4%; odds ratio [OR] 1.50), transfusions (20.6% versus 14.6%; OR 1.38), and re-revisions for prosthetic joint infection (10.9% versus 6.5%; OR 1.73). In subgroup analyses, rates of re-revision for prosthetic joint infection after initial aseptic rTHA (7.1% versus 3.8%; OR 1.82) and periprosthetic fracture after initial septic rTHA (4.5% versus 1.6%; OR 2.77) were significantly higher in the HCV cohort.

CONCLUSION

Similar to primary THA, patients who have HCV exhibit significantly increased complication rates after rTHA. With growing utilization in recent years, these data suggest that this population will comprise an increasingly larger proportion of rTHA procedures performed in the coming years.

Do patient-reported outcome measures improve after aseptic revision total hip arthroplasty?

BACKGROUND

The purpose of this study was to determine patient-reported outcome measures (PROMs) changes in: (1) pain, function and global health; and (2) predictors of PROMs in patients undergoing aseptic revision total hip arthroplasty (rTHA) using a multilevel model with patients nested within surgeon.

METHODS

A prospective cohort of 216 patients with baseline and 1-year PROMs who underwent aseptic rTHA between January 2016 and December 2017 were analysed. The most common indication for rTHA was aseptic loosening, instability, and implant failure. The PROMs included in this study were HOOS Pain and HOOS Physical Function Short-form (PS), Veterans RAND-12 Physical Component Score (VR-12 PCS), and VR-12 Mental Component Score (MCS). Multivariable linear regression models were constructed for predicting 1-year PROMs.

RESULTS

Mean 1-year PROMs improvement for aseptic revisions were 30.4 points for HOOS Pain and 22.1 points for HOOS PS. Predictors of better pain relief were patients with higher baseline pain scores. Predictors of better 1-year function were patients with higher baseline function and patients with a posterolateral hip surgical approach during revision. Although VR-12 PCS scores had an overall improvement, nearly 50% of patients saw no improvement or had worse physical component scores. Only 30.7% of patients reported improvements in VR-12 MCS.

CONCLUSIONS

Overall, patients undergoing aseptic rTHA improved in pain and function PROMs at 1 year. Although global health assessment improved overall, nearly half of aseptic rTHA patients reported no change in physical/mental health status. The associations highlighted in this study can help guide the shared decision-making process by setting expectations before aseptic revision THA.

Enhanced and Stem-Cell-Compatible Effects of Nature-Inspired Antimicrobial Nanotopography and Antimicrobial Peptides to Combat Implant-Associated Infection

Nature-inspired antimicrobial surfaces and antimicrobial peptides (AMPs) have emerged as promising strategies to combat implant-associated infections. In this study, a bioinspired antimicrobial peptide was functionalized onto a nanospike (NS) surface by physical adsorption with the aim that its gradual release into the local environment would enhance inhibition of bacterial growth. Peptide adsorbed on a control flat surface exhibited different release kinetics compared to the nanotopography, but both surfaces showed excellent antibacterial properties. Functionalization with peptide at micromolar concentrations inhibited Escherichia coli growth on the flat surface, Staphylococcus aureus growth on the NS surface, and Staphylococcus epidermidis growth on both the flat and NS surfaces. Based on these data, we propose an enhanced antibacterial mechanism whereby AMPs can render bacterial cell membranes more susceptible to nanospikes, and the membrane deformation induced by nanospikes can increase the surface area for AMPs membrane insertion. Combined, these effects enhance bactericidal activity. Since functionalized nanostructures are highly biocompatible with stem cells, they make promising candidates for next generation antibacterial implant surfaces.

Acetabular Total Hip Arthroplasty Revision: A Summary of Operative Factors, Outcomes, and Comparison of Approaches

BACKGROUND

Revision total hip arthroplasty (THA) presents a greater risk to patients than primary THA, and surgical approach may impact outcomes. This study aimed to summarize acetabular revisions at our institution and to compare outcomes between direct anterior and posterior revision THA.

METHODS

A series of 379 acetabular revision THAs performed from January 2010 through August 2022 was retrospectively reviewed. Preoperative, perioperative, and postoperative factors were summarized for all revisions and compared between direct anterior and posterior revision THA.

RESULTS

The average time to acetabular revision THA was 10 years (range, 0.04 to 44.1), with mechanical failure (36.7%) and metallosis (25.6%) being the most prevalent reasons for revision. No differences in age, body mass index, or sex were noted between groups. Anterior revision patients had a significantly shorter length of stay (2.2 versus 3.2 days, P = .003) and rate of discharge to a skilled nursing facility (7.5 versus 25.2%, P = .008). In the 90-day postoperative period, 9.2% of patients returned to the emergency department (n = 35) and twelve patients (3.2%) experienced a dislocation. There were 13.2% (n = 50) of patients having a rerevision during the follow-up period with a significant difference between anterior and posterior approaches (3.8 versus 14.7%, respectively, P = .049).

CONCLUSION

This study provides some evidence that the anterior approach may be protective against skilled nursing facility discharge and rerevision and contributes to decreased lengths of stay. We recommend surgeons select the surgical approach for revision THA based on clinical preferences and patient factors.

Antibiotic-Loaded Coatings to Reduce Fracture-Related Infections: Retrospective Case Series of Patients with Increased Infectious Risk

Local antibiotic delivery strategies have been increasingly employed for the prevention of fracture-related infections (FRIs). The aim of this study is to evaluate the efficacy and safety of antibiotic-coated implants in the prevention of FRIs after surgical treatment in patients with increased infectious risk. A retrospective observational study has been conducted on patients with upper and lower limb fractures treated with internal fixation or prosthetic replacements, using a gentamicin coated nail (CN) and/or antibiotic-loaded hydrogel applied to the implant of choice (ALH). The study included 37 patients (20 M, 17 F), with a mean age of 63 years. The mean estimated preoperative infectious risk score was 6.4%. ALH was used in 27 cases, tibial CNs were implanted in 4 cases, and both were employed in 6 cases. The antibiotics used locally were gentamicin in 72.97% of cases (27 patients) and a combination of gentamicin + vancomycin in 27.03% of cases (10 patients). Mean follow-up was 32 months. Only one case (2.94%) showed onset of FRI at 5 months after surgery. Local antibiotic prophylaxis by coating resulted in a reduction in the incidence FRI, as compared to the estimated preoperative risk. The use of ALH allows for the choice of antibiotic; however, the application of antibiotics seems more nonuniform when applied to a nail.

A low dislocation rate after revision total hip arthroplasty performed through the anterior approach

BACKGROUND

Dislocation is a major complication in revision total hip arthroplasties. This study aimed to evaluate the dislocation rate, complications, and functional scores of revision total hip arthroplasty performed through the direct anterior approach.

METHODS

Between January 2014 and March 2020, 84 patients undergoing revision total hip arthroplasty were retrospectively reviewed. All operations were performed through the direct anterior approach. At the final follow-up, incidences of dislocation, reoperation, acute deep infections, periprosthetic fractures and psoas impingement were assessed. The median postoperative Oxford Hip Score was also calculated.

RESULTS

At revision surgery, the mean age was 66 ± 12 years (range, 28-91). During an average follow-up of 4.2 ± 1.2 years, reoperation rate for major complications in the non-infected revisions was 15% (n = 11), including five acute deep infections (7%), four periprosthetic fractures (5%), one dislocation and one psoas impingement (1%). The median postoperative Oxford Hip Score was 39 (interquartile range = 14).

CONCLUSION

In our series, revision total hip arthroplasty through direct anterior approach was associated with a very low dislocation rate, acceptable complication rates and good functional results. Our results suggest that this procedure is safe and reliable.

TRIAL REGISTRATION

Ethical approval for this study was obtained, before enrollment of the first participant, by CUB Erasme's research ethics committee (P2020/323) and C.H.U Ambroise Paré's research ethics committee.

[Postoperative outcomes and survival rates after aseptic revision total hip arthroplasty : What can patients expect from revision surgery?]

BACKGROUND

In 2020, more than 14,000 aseptic revision procedures for total hip arthroplasty (THA) were registered in Germany. Patient expectations of revision hip arthroplasty are not substantially different from expectations of primary hip replacement.

OUTCOME

However, revision surgery is associated with increased complication rates and a higher proportion of dissatisfied patients. In particular, poorer postoperative function and mobility as well as increased pain levels following revision THA have been described compared to the outcome after primary THA. Quality of life and return-to-work can also be impaired.

SURVIVAL RATE

Implant survival is influenced by age, BMI, and comorbidities of the patients, but also by the size and complexity of bone defects, the extent of periprosthetic soft tissue compromise and the choice of revision implant(s). In addition, the number of previous revision surgeries inversely correlates with the survival rates. Previous revisions have been shown to be associated with increased risks of aseptic loosening, instability and periprosthetic infection.

Periprosthetic joint infection is the main reason for failure in patients following periprosthetic fracture treated with revision arthroplasty

INTRODUCTION

Periprosthetic fracture after primary total hip and knee arthroplasty (THA; TKA) can be challenging, requiring open reduction internal fixation (ORIF), revision, or both. The aim of this study was to evaluate the outcomes and risk factors associated with re-revision surgery following failed revision arthroplasty for periprosthetic fracture.

METHODS

A total of 316 consecutive THA patients and 79 consecutive TKA patients underwent a revision for periprosthetic fracture, of which 68 THA patients (21.5%) and 15 TKA patients (18.9%) underwent re-revision surgery. The most common indication for hip and knee re-revision was periprosthetic joint infection (PJI) in 28 THA patients (46.6%) and 11 TKA patients (47.8%).

RESULTS

The complication rates of THA and TKA revision were 24.3% and 25.3% respectively, and 35.0% and 39.1% respectively for re-revision surgery at an average follow-up of 4.5 years. Periprosthetic joint infection was the most common indication for THA and TKA re-revision (46.7%; 47.8%) and third revision surgery (15.0%; 13.0%). Factors significantly contributing to an increased risk of THA and TKA re-revision included revision with plate fixation and revision with combined ORIF.

CONCLUSION

The overall complication rate of THA and TKA re-revision surgery following failed revision surgery for periprosthetic fracture was higher than of revision surgery. The most common indication for re-revision and third revision was periprosthetic joint infection. These findings may assist surgeons in the management and preoperative counseling of patients undergoing THA and TKA revision surgery for a periprosthetic fracture to optimize the outcomes for these patients.

LEVEL OF EVIDENCE

Level III, case-control retrospective analysis.

Pre-operative planning and templating with 3-D printed models for complex primary and revision total hip arthroplasty

Background

Complex primary and revision THR requires comprehensive understanding of abnormal bony anatomy. Evaluation and classification of acetabular bone defects is essential to manage them appropriately. It is difficult to appreciate complex defects using conventional 2-Dimensional radiological modalities. 3D printed models can provide both visual and tactile reproduction of the bony anatomy, with potential for better pre-operative planning and making these complex surgeries more precise and accurate.

Materials and methods

Anatomical 3D models of pelvis and femur were made based on CT scans of 27 patients undergoing complex primary THR/Revision THR by FDM (Fusion Deposition Modeling) technology using Flash Forge-Dreamer 3D printer with ABS (plastic) material. Models were used for pre-operative planning and simulation of surgery. Aims of the study were to study the accuracy of 3D models in predicting the implant sizes, accuracy in evaluation of acetabular bone defects and validating the utility of 3 D models through surgeon feedback.

Results

The acetabular cup size and placement was accurate in 25 (92.6%) patients. Preoperative acetabular bone defect was accurately estimated in all the patients. There were no neurovascular complications at early and 1-year follow-up in this case series. Model realism and reliability survey response from five surgeons was graded, with average overall usefulness of 3D models of 4.86/5, average model realism was 4.9/5, average usefulness for planning was 4.74/5 and usefulness for teaching was 5/5.

Conclusion

3D models are accurate and help in assessing acetabular bone deficiencies reliably in complex and revision THR. Anatomical models help in surgical planning and simulation, enabling surgeons in predicting the correct implant sizes and importantly placement of acetabular cup and for management of bone defects. The safe trajectory of acetabular screws can be simulated and determined, thereby avoiding penetration into pelvis and neuro-vascular injuries.

Stay Short or Go Long in Revision Total Hip Arthroplasty With Paprosky Type II Femoral Defects: A Comparative Study With the Use of an Uncemented Distal Fixating Modular Stem and a Primary Monobloc Conical Stem With 5-Year Follow-Up

BACKGROUND

In the revisions for Paprosky type II femoral defects, diaphyseal fixating femoral stems are commonly used. To preserve bone stock, the use of a shorter primary conical stem could be an adequate alternative. The objective of this study is to compare the results of a primary conical stem to the more commonly used diaphyseal fixating modular revision stem in revision total hip arthroplasty surgery with Paprosky type II femoral defects.

METHODS

A total of 59 consecutive patients with Paprosky type II femoral defects from our prospective revision registry were included. Thirty patients who received a long distal fixating modular stem (Revision Stem, Lima Corporate) and 29 patients who received a primary conical short stem (Wagner Cone, Zimmer) were prospectively followed. Minimal follow-up time was 2 years for subsidence and patient-reported outcome measures and 5 years for complications, reoperation, and revision. We compared subsidence, perioperative complications, reoperations, femoral component survival, Oxford Hip Score, EuroQol 5 Dimension, visual analog scale (VAS) for pain at rest, and VAS for pain during activity between stems.

RESULTS

Both groups were comparable regarding demographic, clinical, and surgery-related characteristics. We found more perioperative complications and stem revisions with the modular revision stem than with the primary conical stem. There were no statistical differences in subsidence, EuroQol 5 Dimension, Oxford Hip Score, and VAS for pain at rest or during activity between both stems.

CONCLUSION

In revision total hip arthroplasty with Paprosky type II femoral defects, uncemented primary monobloc conical femoral stems showed the same clinical result as distal fixating modular stems with fewer complications and fewer stem revisions.

Post-operative prophylactic antibiotics in aseptic revision hip and knee arthroplasty: a propensity score matching analysis

The use of extended antibiotic (EA) prophylaxis (> 24 h) remains controversial in aseptic revision arthroplasty. We sought to determine whether EA prophylaxis reduces the risk of periprosthetic joint infection (PJI) in aseptic revision hip and knee arthroplasty. A total of 2800 patients undergoing aseptic revision hip and knee arthroplasty at five institutional databases from 2008 to 2017 were evaluated. One to two nearest-neighbor propensity score matching analysis was conducted between patients who did and did not receive extended antibiotic prophylaxis. The matching elements included age, sex, body mass index, Charlson comorbidity index, hospital distribution, year of surgery, joint (hip or knee), surgical time, CRP, preoperative hemoglobin, albumin, and length of stay. The primary outcome was the development of PJI, which was assessed at 30 days, 90 days, and 1 year following revision and analyzed separately. A total of 2467 (88%) patients received EA prophylaxis, and 333 (12%) patients received standard antibiotic (SA) prophylaxis (≤ 24 h). In the propensity-matched analysis, there was no difference between patients who received EA prophylaxis and those who did not in terms of 30-day PJI (0.3% vs. 0.3%, p = 1.00), 90-day PJI (1.7% vs. 2.1%, p = 0.62) and 1- year PJI (3.8% vs. 6.0%, p = 0.109). For revision hip, the incidence of PJI was 0.2% vs 0% at 30 days (p = 0.482), 1.6% vs 1.4% at 90 days (p = 0.837), and 3.4% vs 5.1% at 1 year (p = 0.305) in the EA and SA group. For revision knee, the incidence of PJI was 0.4% vs 0.9% at 30 days (p = 0.63), 1.8% vs 3.4% at 90 days (p = 0.331), and 4.4% vs 7.8% at 1 year (p = 0.203) in the EA and SA group. A post hoc power analysis revealed an adequate sample size with a beta value of 83%. In addition, the risks of Clostridium difficile and resistant organism infection were not increased. This multi-institutional study demonstrated no difference in the rate of PJIs between patients who received extended antibiotic prophylaxis and those who did not in aseptic revision arthroplasty. The risk of C. difficile and resistant organism infection was not increased with prolonged antibiotic use.

Periprosthetic Infection in the Setting of Periprosthetic Total Hip Fractures: Evaluation and Management

The incidences of periprosthetic fracture and periprosthetic joint infection after total hip arthroplasty are expected to increase exponentially over the coming decades. Epidemiologic data suggest that many periprosthetic fractures after THA occur concurrently with a loose femoral implant. Recent studies suggest an approximately 8% incidence of indolent infection in cases of suspected aseptic loosening. The available data, therefore, suggest that periprosthetic fracture and infection may coexist, and this possibility should be considered, particularly in patients with a loose femoral stem and high pretest possibility. Although currently limited, the available literature provides some guidance as how to manage this complex issue.

Clinical and radiological outcomes of jumbo cup in revision total hip arthroplasty: A systematic review

Introduction

Many studies have reported the clinical outcomes of a jumbo cup in revision total hip arthroplasty (rTHA) with acetabular bone defect. We conducted a systematic review to access the survivorship and clinical and radiological outcomes of a jumbo cup in rTHA.

Methods

A systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. A comprehensive literature search from PubMed, MEDLINE, EMBASE, and the Cochrane Database of Systematic Reviews was performed with the keywords (“revision” OR “revision surgery” OR “revision arthroplasty”) AND (“total hip arthroplasty” OR “total hip replacement” OR “THA” OR “THR”) AND (“jumbo cup” OR “jumbo component” OR “extra-large cup” OR “extra-large component”). Studies reporting the clinical or radiological outcomes were included. The basic information and radiological and clinical results of these studies were extracted and summarized for analysis.

Results

A total of 19 articles were included in the systematic review. The analysis of clinical results included 953 hips in 14 studies. The re-revision-free survivorship of the jumbo cup was 95.0% at a mean follow-up of 9.3 years. Dislocation, aseptic loosening, and periprosthetic joint infection were the top three complications with an incidence of 5.9%, 3.0%, and 2.1%, respectively. The postrevision hip center was relatively elevated 10.3 mm on average; the mean postoperative leg-length discrepancy was 5.4 mm.

Conclusion

A jumbo cup is a favorable option for acetabular bone defect reconstruction in rTHA with satisfying survivorship and acceptable complication rates.

What Is the Outcome of the First Revision Procedure of Primary THA for Osteoarthritis? A Study From the Australian Orthopaedic Association National Joint Replacement Registry

BACKGROUND

Joint arthroplasty registries traditionally report survivorship outcomes mainly on primary joint arthroplasty. The outcome of first revision procedures is less commonly reported, because large numbers of primary procedures are required to analyze a sufficient number of first revision procedures. Additionally, adequate linkage of primary procedures to revisions and mortality is required. When undertaking revision hip surgery, it is important for surgeons to understand the outcomes of these procedures to better inform patients.

QUESTIONS/PURPOSES

Using data from a large national joint registry, we asked: (1) What is the overall rate of revision of the first aseptic revision procedure for a primary THA? (2) Does the rate of revision of the first revision vary by the diagnosis for the first revision? (3) What is the mortality after the first revision, and does it vary by the reason for first revision?

METHODS

The Australian Orthopaedic Association National Joint Replacement Registry longitudinally maintains data on all primary and revision joint arthroplasties, with nearly 100% capture. The analyses for this study were performed on primary THA procedures in patients with a diagnosis of osteoarthritis up to December 31, 2020, who had undergone subsequent revision. We excluded all primary THAs involving metal-on-metal and ceramic-on-metal bearing surfaces and prostheses with exchangeable necks because these designs may have particular issues associated with revisions, such as extensive soft tissue destruction, that are not seen with conventional bearings, making a comparative analysis of the first revision involving these bearing surfaces more complicated. Metal-on-metal bearing surfaces have not been used in Australia since 2017. We identified 17,046 first revision procedures from the above study population and after exclusions, included 13,713 first revision procedures in the analyses. The mean age at the first revision was 71 ± 11 years, and 55% (7496 of 13,713) of the patients were women. The median (IQR) time from the primary procedure to the first revision was 3 years (0.3 to 7.3), ranging from 0.8 years for the diagnosis of dislocation and instability to 10 years for osteolysis. There was some variation depending on the reason for the first revision. For example, patients undergoing revision for fracture were slightly older (mean age 76 ± 11 years) and patients undergoing revision for dislocation were more likely to be women (61% [2213 of 3620]). The registry has endeavored to standardize the sequence of revisions and uses a numerical approach to describe revision procedures. The first revision is the revision of a primary procedure, the second revision is the revision of the first revision, and so on. We therefore described the outcome of the first revision as the cumulative percent second revision. The outcome measure was the cumulative percent revision, which was defined using Kaplan-Meier estimates of survivorship to describe the time to the second revision. Hazard ratios from Cox proportional hazards models, adjusting for age and gender, were performed to compare the revision rates among groups. When possible, the cumulative percent second revision at the longest follow-up timepoint was determined with the available data, and when there were insufficient numbers, we used appropriate earlier time periods.

RESULTS

The cumulative percent second revision at 18 years was 26% (95% confidence interval [CI] 24% to 28%). When comparing the outcome of the first revision by reason, prosthesis dislocation or instability had the highest rate of second revision compared with the other reasons for first revision. Dual-mobility prostheses had a lower rate of second revision for dislocation or instability than head sizes 32 mm or smaller and when compared to constrained prostheses after 3 months. There was no difference between dual-mobility prostheses and head sizes larger than 32 mm. There were no differences in the rate of second revision when first revisions for loosening, periprosthetic fracture, and osteolysis were compared. If cemented femoral fixation was performed at the time of the first revision, there was a higher cumulative percent second revision for loosening than cementless fixation from 6 months to 6 years, and after this time, there was no difference. The overall mortality after a first revision of primary conventional THA was 1% at 30 days, 2% at 90 days, 5% at 1 year, and 40% at 10 years. A first revision for periprosthetic fracture had the highest mortality at all timepoints compared with other reasons for the first revision.

CONCLUSION

Larger head sizes and dual-mobility cups may help reduce further revisions for dislocation, and the use of cementless stems for a first revision for loosening seems advantageous. Surgeons may counsel patients about the higher risk of death after first revision procedures, particularly if the first revision is performed for periprosthetic fracture.Level of Evidence Level III, therapeutic study.

Utilisation of calcium sulphate beads in one-stage aseptic revision total hip arthroplasty

INTRODUCTION

Periprosthetic joint infection (PJI) affects many revision total hip arthroplasty (THA) patients, contributing to a concomitant rise in revision costs. Means of decreasing the risk of PJI include the use of antibiotic adjuncts, such as calcium sulphate beads (CSBs). Mixed with antibiotics, the potential benefits of CSBs include dissolvability and antibiotic drug elution. However, information comparing them in aseptic revision is scarce. Therefore, this study investigated CSB utilisation for infection prevention in aseptic revision THA. Specifically, we compared (1) infection rates; (2) lengths of stay; (3) subsequent infection procedures; and (4) final surgical outcome in 1-stage aseptic revision THA patients who did received CSBs to 1-stage aseptic revision THA patients who did not.

METHODS

A retrospective chart review was performed to identify all patients who underwent an aseptic revision THA between January 2013 and December 2017. Patients who received CSBs (n = 48) were compared to non-CSB patients (n = 58) on the following outcomes: postoperative infections, lengths of stay (LOS), subsequent irrigation and debridements (I+Ds), and final surgical outcome, classified as successful THA reimplantation, retained antibiotic spacer, or Girdlestone procedure. Chi-square and t-testing were used to analyse the variables.

RESULTS

There was no significant differences found between CSB patients and non-CSB patients in postoperative infections (p = 0.082), LOS (p = 0.179), I+Ds (p = 0.068), and final surgical outcome (p = 0.211).

CONCLUSION

This study did not find any statistical difference between CSBs and standard of care in infection rates and surgical outcomes. The advantage of these beads for 1-stage aseptic revisions is questionable.

The Incidence of Severe Hypercalcaemia-Induced Mental Status Changes in Patients Treated with Antibiotic-Loaded Calcium Sulphate Depot for Orthopaedic Infections

Local application of antibiotics with calcium-containing carrier materials (CCCM) might deliver large quantities of calcium, with some cases of hypercalcaemia reported. The incidence of symptomatic hypercalcaemia was estimated retrospectively in a consecutive, prospective series of patients treated between 10/2006 and 02/2019 with antibiotic-loaded CCCM for various orthopaedic infections. Risk factors were analysed. In the study period, 215 CCCM applications were performed. Two patients (0.9%) developed symptomatic hypercalcaemia. In one case, hypercalcaemia occurred 14 days after a second CCCM application during a staged septic hip revision. In the other case, hypercalcaemia became symptomatic six days after application of vancomycin-loaded CCCM in a component-retaining septic revision hip arthroplasty. In both cases, hypercalcemia was not imputable solely to the CCCM. Prolonged immobilization, renal impairment and other specific risk factors were present. Implantation of a CCCM for local application of antibiotics exposes the patient to large quantities of calcium during dissolution. This might induce symptomatic hypercalcaemia, a potentially life-threatening complication. The observed incidence of symptomatic hypercalcaemia remained rare (<1%). In some patients, compensatory mechanisms might be overwhelmed in the presence of other risk factors. Postoperative monitoring of calcaemia as well as elimination of risk factors is mandatory for all patients treated with CCCM.