Decreased Patellar Fractures and Subluxation With Patellar Component Replacement at Stage-One Spacer

BACKGROUND

Periprosthetic joint infection is a devastating complication of total knee arthroplasty and is often treated with 2-stage revision. We retrospectively assessed whether replacing the patellar component with articulating stage-one spacers was associated with improved outcomes compared to spacers without patellar component replacement.

METHODS

A total of 139 patients from a single academic institution were identified who underwent an articulating stage-one revision total knee arthroplasty and had at least 1-year follow-up. Of the 139 patients, 91 underwent patellar component removal without replacement, while 48 had a patellar component replaced at stage-one revision. Patellar fracture and reinfection at any point after stage-one were recorded. Knee range of motion (ROM), patellar thickness, lateral tilt, and lateral displacement were measured at 6-weeks post stage-one. Chi-square, Fisher's exact, and t-tests were utilized for comparisons. There were no significant demographic differences between groups.

RESULTS

Patellar component replacement at stage-one revision was associated with fewer patellar fractures (2.1 versus 12.1%, P = .046), less lateral patellar displacement (1.7 versus 16.0 mm, P < .01), and improved pre to postoperative knee ROM 6 weeks after stage-one (+5.9 versus -11.4°, P = .03). There was no difference in reinfections after stage-2 revision for the replaced or unreplaced patellar groups (15.4 versus 15%, P = 1.000). While the mean time between stage-one and stage-2 was not different (5.2 versus 4.5 months, P = .50), at one-year follow-up, significantly more patients in the patellar component replacement group were satisfied and refused stage-2 revision (45.8 versus 3.3%, P < .001).

CONCLUSIONS

Replacing the patellar component at stage-one revision is associated with a decreased rate of patellar fracture and lateral patellar subluxation, improved ROM, and possible increased patient satisfaction, as reflected by nearly half of these patients electing to keep their spacer. There was no difference in reinfection rates between the cohorts.

Total Knee Arthroplasty Kinematics Predict Patient-Reported Outcome Measures: Implications for Clinical Kinematic Examinations

BACKGROUND

A core tenet of total knee arthroplasty (TKA) is that achieving more natural kinematics will lead to superior patient outcomes. Yet this relationship has not been proven for large representative cohorts of TKA patients because accurately measuring 3-dimensional TKA kinematics is time-consuming and expensive. But advanced imaging systems and machine learning-enhanced analysis software will soon make it practical to measure knee kinematics preoperatively and postoperatively in the clinic using radiographic methods. The purpose of this study was to assess the reported relationships between TKA kinematics and outcomes and distill those findings into a proposal for a clinically practical protocol for a clinical kinematic exam.

METHODS

This study reviewed the recent literature relating TKA kinematics to patient outcomes. There were 10 studies that reported statistical associations between TKA kinematics and patient outcome scores utilizing a range of functional activities. We stratified these activities by the complexity of the radiographic examination to create a proposed examination protocol, and we generated a list of requirements and characteristics for a practical TKA clinical kinematic examination.

RESULTS

Given considerations for a clinically practical kinematic exam, including equipment, time and other resources, we propose 3 exam levels. With basic radiographs, we suggest studying single-leg stance in extension, lunge or squat, and kneeling. For fluoroscopic systems with X-ray pulses up to 20 ms, we propose chair-rise or stair ascent to provide additional dynamic information. For fluoroscopic systems with X-ray pulses of less than 10 ms, we propose rapid open-chain knee flexion-extension to simulate the highly dynamic swing phase of gait.

CONCLUSIONS

It is our hope that this proposed examination protocol spurs discussion and debate so that there can be a consensus approach to clinical examination of knee and TKA kinematics when the rapidly advancing hardware and software capabilities are in place to do so.

Metaphyseal Fixation Using Cones and Sleeves for Severe Proximal Tibial Bone Loss

BACKGROUND

Tibial bone defects are commonly encountered in revision total knee arthroplasty (rTKA) and can be managed with metaphyseal cones or sleeves. Few studies have directly compared tibial cones and sleeves in rTKA, and none have limited this comparison to the most severe tibial defects. The purpose of this study was to evaluate and compare the outcomes of metaphyseal cones and sleeves for tibial reconstruction in rTKA regarding implant fixation and clinical outcomes.

METHODS

A retrospective review was conducted on patients undergoing rTKA in which metaphyseal cones or sleeves were utilized for addressing metaphyseal bone loss (34 cones and 18 sleeves). Tibial bone loss was classified according to the Anderson Orthopaedic Research Institute bone defect classification, with types 2B and 3 being included. Patient-reported outcomes and postoperative complications were collected, and a radiographic evaluation of osseointegration or loosening was performed.

RESULTS

There were 52 knees included (34 cones, 18 sleeves), with a median follow-up of 41.0 months. All-cause implant survival was 100% at 2 years and 96% (95% confidence interval: 76 to 99%) at 4 years, with 98% of tibial components demonstrating osseointegration at the final follow-up. During follow-up, there were a total 11 revisions, of which 1 sleeve was revised secondary to implant loosening. Tibial sleeves had a higher risk of revision compared to tibial cones (P < .01), and sleeves fixed with a hybrid technique were more likely to need revision than cones fixed by the same method (P = .01).

CONCLUSIONS

Porous metaphyseal tibial cones and tibial metaphyseal sleeves both performed well at a 41-month median follow-up with no difference in aseptic survivorship between the 2 constructs. Both demonstrate high rates of osseointegration, low rates of aseptic failure, and significant improvement in Knee Society Scores in patients with severe tibial defects in rTKA.

A comparison of the top 500 papers in Clinical Nutrition ranked by citation and Altmetric Attention Scores

BACKGROUND AND AIMS

Citation scores (CS) have been traditionally used to measure the impact of scientific publications. Sourced from the Internet, Altmetric Attention Scores (AAS) are complementary metrics that assess how often publications are discussed and used globally. We compared by rank the top 500 papers by CS and AAS published in Clinical Nutrition with corresponding AAS and CS.

METHODS

A search for all publications in Clinical Nutrition was performed on Dimensions (https://app.dimensions.ai/discover/publication) on 3rd April 2024. Outputs were ranked according to CS and then by AAS with the top 500 in each category selected. Scores, year and type of publication were recorded. Correlation was expressed as the Spearman's rank coefficient (ϱ).

RESULTS

We identified 18,790 outputs. Within the top 500 publications ranked by CS, there was a significant weak positive correlation (ϱ = 0.235, P < 0.0001) between CS [median (IQR) 149 (116-223)] and AAS [7 (3-22)]. Ranked by AAS, there was a non-significant very weak positive correlation (ϱ = 0.072, P = 0.106) between AAS [55.5 (36-115)] and CS [42 (16.5-94.5)]. Trends remained similar when grouped by publication type. Guidelines, ranked by CS, had the highest CS and ranked by AAS, the highest CS and AAS. Publications per year, by year, ranked by CS, had a negatively skewed distribution peaking in 2012 and declined thereafter, but when ranked by AAS, had a moderately positive linear trend from 2001 to 2024 (ϱ = 0.513, P < 0.0001).

CONCLUSION

Correlation between CS and AAS was weak. Guidelines had the highest CS and AAS. CS are iterative taking years to mature while AAS are immediate.

Regional Differences in Primary Total Knee Arthroplasty Utilization, Physician Reimbursement, and Patient Characteristics

Background

The primary purpose of this study was to evaluate how utilization, physician reimbursement, and patient populations have changed for primary total knee arthroplasty (TKA) from 2013 to 2021 at both a regional and national level within the Medicare population.

Methods

The Medicare Physician and Other Practitioners database was queried for all episodes of primary TKA between years 2013 and 2021. TKA utilization per 10,000 beneficiaries, inflation-adjusted physician reimbursement per TKA, and patient demographics of each TKA surgeon were extracted each year. Data were stratified geographically, and Kruskal-Wallis tests were utilized.

Results

Between 2013 and 2021, TKA utilization per 10,000 beneficiaries increased at the greatest rate in the Northeast (+15.1%). In 2021, TKA utilization was highest in the Midwest (97.6/10,000; P < .001). The Midwest had the greatest decline in average physician reimbursement per TKA between 2013 and 2021 (-26.3%) and the lowest average reimbursement ($988.70, P < .001) in 2021. Alternatively, the Northeast had the smallest decline in average TKA reimbursement (-22.6%). Nationally, the average number of beneficiaries per TKA surgeon declined (-6.8%), while the average number of TKAs per surgeon (+5.7%) and average services per beneficiary (+24.3%) both increased. The average number of patient comorbidities and proportion of patients with dual Medicare-Medicaid eligibility decreased over time across all regions.

Conclusions

This study demonstrates that TKA utilization is increasing and average physician reimbursement per TKA is declining at varying rates across the country, with the Northeast and Midwest most affected. These findings should be addressed in policy discussions to ensure equitable arthroplasty care.

The Trend of Medicare Reimbursement for Total Joint Arthroplasty: Using Mathematical Models to Predict Possible Per-Hour Rate Out to 2030

Background

While multiple studies have assessed the trends of Medicare reimbursement for orthopedic total joint arthroplasty (TJA) surgeries, none have forecasted reimbursement in relatable per-hour figures. The purposes of this study are to examine trends of reimbursement for primary and revision TJA and translate forecasted primary TJA reimbursement to relatable per-hour compensation.

Methods

The Center for Medicare and Medicaid Services reimbursement data from 1992 to 2024 were used to create a historical view of reimbursement for primary and revision TJA. All monetary values were converted to 2023 USD to account for inflation. Polynomial and linear forecast equations were used to predict the future of the TJA reimbursement to 2030. Relative Value Scale Update Committee standard times for procedures were used with the forecasts to establish per-hour rates.

Results

Total reimbursement for primary total hip arthroplasty/total knee arthroplasty is forecasted to decrease 85.36%/86.14% by 2030. Using prior trends in reimbursement, TJA procedures are predicted to reimburse at or less than $100.00 2023 USD per Medicare case by 2030. Moreover, TJA surgeons are forecasted to earn $13.93/h per primary total hip arthroplasty and $14.97/h per primary total knee arthroplasty by 2030.

Conclusions

This study highlights the concerning trends for both primary and revision arthroplasties as TJA surgeons are on a path to earn below minimum wage for primary TJAs by 2030. Mathematical models forecast a bleak future for orthopedic TJA reimbursement. This downward trajectory poses a risk to access and quality of care.

Enhancing robotic precision in medial UKA: Image-based robot-assisted system had higher accuracy in implant positioning than imageless robot-assisted system across 292 knees

PURPOSE

The objective of this study was to compare the degree of accuracy in implant positioning and limb alignment offered by two robot-assisted (RA) systems: an image-based robot-assisted (IBRA) versus an imageless robot-assisted (ILRA) system for the treatment of medial knee osteoarthritis with unicompartmental knee arthroplasty (UKA).

METHODS

This retrospective radiographic study included medial UKAs performed between 2011 and 2023. Radiographic measurements taken preoperatively and at 1-year postoperative control visit focusing on hip-knee-ankle angle (HKA), posterior tibial slope (PTS), tibial component coronal alignment relative to Cartier's angle and restoration of proper joint line (JL) height were analyzed. Outliers for postoperative measurements were defined as follows: HKA <175° or >180°, PTS <2° or >8°, >3° or <-3° alterations in Cartier's angle and ±2 mm changes in the height of the joint line.

RESULTS

The final sample consisted of 292 medial UKAs: 95 (32.5%) with an IBRA system and 197 (67.5%) with an ILRA system. Implant positioning and limb alignment were more accurate in the group of patients treated with IBRA, HKA (77.9% vs. 67.5%, p = 0.07), PTS (93.7% vs. 82.7%, p = 0.01), restoration of tibial varus relative to Cartier's angle (87.4% vs. 65%, p < 0.001) and restoration of JL height (81.1% vs. 69.5%, p = 0.04).

CONCLUSION

Medial UKA surgery using an IBRA system was associated with a higher degree of accuracy in implant positioning and postoperative limb alignment as compared to an ILRA system. This is a valuable contribution to help communicate the advantages of using this surgical technique and improve its reproducibility.

LEVEL OF EVIDENCE

Level III, Retrospective cohort study.

Integrating Smartphone Applications and Wearable Devices for Postoperative Rehabilitation in Total Knee Arthroplasty: A Critical Review

BACKGROUND

Smartphone and wearable technologies offer innovative methods for monitoring postoperative recovery in total knee arthroplasty (TKA) patients. This review assessed the benefits of these technologies in postoperative care, focusing on (1) smartphone applications, (2) wearable devices, and (3) their combination.

METHODS

A systematic search identified studies on smartphone applications and wearables for post-TKA monitoring. The review analyzed 2,119 studies, with 58 meeting criteria: 25 on applications, 25 on wearables, and 8 on both. Studies were rated with a methodology index as well as by levels of evidence. They were then analyzed by categorizing them by adherence and patient satisfaction, functional outcomes and pain scores, gait analyses and ranges of motion, and measurement and comparison tools.

RESULTS

A review of 24 of 25 publications related to smartphone applications used for postoperative recovery in TKA showed the potential for improved patient's satisfaction, gait recovery, pain medication scheduling guidance with improved pain management, cost savings, and functional outcomes. Wearable technologies used in postoperative recovery demonstrated monitoring accuracy in 25 studies. These devices also showed effectiveness in gait and motion analysis. Other demonstrated benefits of the wearables were improved outcomes, return to function, cost reduction, and again, better management of pain due to patient interaction and guidance. Studies that combined applications and wearables demonstrated the individual findings with the addition of adherence, patient's satisfaction, and overall mobility improvement at 3 months.

CONCLUSIONS

Smartphone applications and wearables can enhance postoperative rehabilitation for TKA patients. Smartphone applications and wearables have been shown in randomized trials to be accurate, effective, and useful in the postoperative rehabilitation of TKA patients. A recurring theme in the review was improved adherence to care plans and medication schedules that ultimately result in improved functional outcomes. These technologies and the data that they generate offer direct patient benefits and the potential for future cost savings.

Knee Arthroscopy Following Total Knee Arthroplasty is Not Associated With an Elevated Risk of Infection

BACKGROUND

Recent literature has suggested that knee arthroscopy (KA) following ipsilateral primary total knee arthroplasty (TKA) may be associated with an increased risk of periprosthetic joint infection (PJI). However, prior studies on this subject have relied on insurance databases or have lacked control groups for comparison. This study aimed to evaluate the risk of PJI in patients undergoing ipsilateral KA after primary TKA at a single institution.

METHODS

Our total joint registry was queried to identify 167 patients (178 knees) who underwent ipsilateral KA for any indication other than infection following primary TKA (KA + TKA group). The average time from TKA to KA was 2.1 ± 2.3 years. The average follow-up from primary TKA and from KA was 8.4 ± 5.4 years and 6.3 ± 5.4 years, respectively. The mean patient age was 63 ± 11 years, the mean body mass index was 31 ± 5, and 64% were women. The most common indications for KA were patellar clunk or patellofemoral synovial hyperplasia (66%) and arthrofibrosis (16%). Patients in the KA + TKA group were matched to 523 patients who underwent TKA without subsequent KA (TKA group) based on age, sex, date of surgery, and body mass index. The primary outcome measure was survivorship free from PJI.

RESULTS

There was no statistical difference in the overall rate of PJI between the KA + TKA group (n = 2, 1.1%) compared to the TKA group (n = 3, 0.6%) (hazard ratio 2.0, 95% confidence interval 0.3 to 12.0, P = .4). At 5 and 10 years after TKA, there was no difference in survivorship free of PJI between the 2 groups (P = .8 and P = .3, respectively).

CONCLUSIONS

A PJI is a rare complication of KA after TKA. The rate of PJI in patients undergoing KA following TKA is not significantly increased.

LEVEL OF EVIDENCE

III.

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.

Prevention and treatment of peri-implant fibrosis by functionally inhibiting skeletal cells expressing the leptin receptor

The cellular and molecular mediators of peri-implant fibrosis-a most common reason for implant failure and for surgical revision after the replacement of a prosthetic joint-remain unclear. Here we show that peri-implant fibrotic tissue in mice and humans is largely composed of a specific population of skeletal cells expressing the leptin receptor (LEPR) and that these cells are necessary and sufficient to generate and maintain peri-implant fibrotic tissue. In a mouse model of tibial implantation and osseointegration that mimics partial knee arthroplasty, genetic ablation of LEPR+ cells prevented peri-implant fibrosis and the implantation of LEPR+ cells from peri-implant fibrotic tissue was sufficient to induce fibrosis in secondary hosts. Conditional deletion of the adhesion G-protein-coupled receptor F5 (ADGRF5) in LEPR+ cells attenuated peri-implant fibrosis while augmenting peri-implant bone formation, and ADGRF5 inhibition by the intra-articular or systemic administration of neutralizing anti-ADGRF5 in the mice prevented and reversed peri-implant fibrosis. Pharmaceutical agents that inhibit the ADGRF5 pathway in LEPR+ cells may be used to prevent and treat peri-implant fibrosis.

A pilot multicentre randomised clinical trial to determine the effect of a pharmacist-partnered opioid tapering intervention before total hip or knee arthroplasty

BACKGROUND

Opioid analgesic use before total hip or knee arthroplasty has been associated with worse postoperative outcomes. This pilot study aimed to examine the feasibility of a telehealth-based pharmacist-partnered opioid tapering intervention before elective primary hip or knee arthroplasty and its potential effectiveness compared with usual care.

METHODS

This study was conducted at seven hospitals in New South Wales, Australia. Eligible patients were those aged ≥ 18 years, scheduled to undergo primary hip or knee arthroplasty for osteoarthritis and taking opioid analgesics pre-operatively. The intervention group participated in an opioid tapering telehealth service, a partnership between a pharmacist and general practitioner, for 3 months pre-operatively up to the day of surgery, while the control group received usual care. The primary outcomes of the study were to investigate the feasibility of the intervention (i.e. adherence to treatment) and potential effectiveness in decreasing baseline daily opioid dose by > 50% before surgery.

RESULTS

Between December 2021 and June 2023, 70 patients were recruited and assigned randomly to the intervention group (n = 35) or control group (n = 35). Baseline characteristics were similar between groups. Thirty patients in each group completed their allocated treatment. All patients allocated to the intervention group completed at least one appointment with a pharmacist, with the median (IQR [range]) being 2 (1-4 [1-6]) appointments. The number of patients who successfully decreased their baseline daily opioid dose by ≥ 50% before surgery was 27/30 in the intervention group compared with 5/30 in the usual care group (p < 0.001).

CONCLUSIONS

The findings of this pilot study support the feasibility of a telehealth-delivered, pharmacist-partnered opioid tapering service for patients scheduled for primary hip or knee arthroplasty. A broader multicentre study to examine the effectiveness of this intervention on clinical outcomes is warranted.

Same Day Discharge Total Knee Arthroplasty: Hospital Demonstrates Similar Outcomes to Ambulatory Surgery Center in a More Complex Patient Population

BACKGROUND

The purpose of this study was to compare outcomes between patients undergoing same-day discharge (SDD) total knee arthroplasty (TKA) at an ambulatory surgery center (ASC) versus a tertiary care university hospital setting.

METHODS

A single tertiary academic center's institutional database was reviewed for patients that underwent primary TKA and were discharged the same day from August 2021 to January 2024. Patients who did not have at least one year of follow-up were excluded. Patient demographics, comorbidities, patient-reported outcome measures (PROMs), emergency department (ED) visits, admissions, reoperations, and revisions were collected. Patients were stratified by the location of their surgery: ASC versus hospital. Specific criteria had to be met prior to surgery at the ASC, and the final decision regarding the location of surgery was made via shared decision-making between the patient and their surgeon. Patients who did not meet ASC criteria underwent TKA at the main hospital. Univariable analyses were used to compare groups, and multivariable logistic regression was used to determine if surgical location was a significant factor. Of the 449 TKAs meeting inclusion criteria, 63.3% (284) were performed at the ASC and 36.7% (165) at the university hospital at a mean follow-up of 1.51 years (range, 1.00 to 2.40). Of those 165 whose surgery was done at the hospital, 93.9% met at least one ASC exclusion criteria.

RESULTS

Patients whose TKA was done at the hospital had significantly higher weight (P = 0.003), body mass index (BMI) (P < 0.001), Elixhauser comorbidity index (ECI) (P < 0.001), proportion of patients who had an American Society of Anesthesiologists (ASA) classification of 3 (P = 0.023), and proportion of patients who required general anesthesia (P < 0.001). Additionally, patients whose TKA was done at the hospital had higher preoperative patient-reported outcome measurement information system (PROMIS) pain interference (PI) (62.0 [59.0, 66.0] versus 63.0 [61.8, 67.0]; P = 0.006), and lower physical function (PF) (39.0 [36.0, 43.0] versus 38.0 [34.0, 41.0]; P = 0.001). At 1 year, however, patients in both groups had similar PROMIS PI (53.0 [49.0, 59.0] versus 54.0 [44.0, 59.0]; P = 0.785) and PROMIS PF (47.0 [42.0, 51.0] versus 47.0 [41.0, 50.0]; P = 0422) scores as well as similar rates of achieving minimum clinically important difference (MCID) for PROMIS PI (64.4 versus 71.4%; P = 0.336) and PROMIS PF (60.5 versus 71.4%; P = 0.124). They also had a similar number of ED visits and admissions at 30 and 90 days, as well as similar reoperation-free (92.0 versus 93.3%; P = 0.79) and revision-free (95.5 versus 99.4%; P = 0.59) survival at 2 years.

CONCLUSION

Although ASCs have strict patient criteria for SDD TKA, complex patients at a tertiary university hospital can be sent home the same day with equivalent outcomes. Therefore, unhealthier patients can safely achieve SDD without compromising outcomes if done in the appropriate setting.

Comparison of Five-Day vs. Fourteen-Day Incubation of Cultures for Diagnosis of Periprosthetic Joint Infection in Hip Arthroplasty

Background: Periprosthetic joint infections (PJI) are among the most morbid complications in total hip arthroplasty (THA). The ideal incubation time, however, for intraoperative cultures for PJI diagnosis remains unclear. As such, the aim of this study was to determine if any differences existed in culture-positive rates and organism detection between five-day and fourteen-day cultures. Methods: This retrospective cohort study consisted of THA cases diagnosed with PJI performed between May 2014 and May 2020 at a single tertiary-care institution. Analyses compared five-day and fourteen-day cultures and carried out a pre-specified subgroup analysis by organism and PJI type. Results: A total of 147 surgeries were performed in 101 patients (57.1% females), of which 65% (n = 98) obtained five-day cultures and 34% (n = 49) obtained fourteen-day cultures. The positive culture rate was 67.3% (n = 99) with Staphylococcus aureus being the most common pathogen identified (n = 41 specimens, 41.4%). The positive culture rate was not significantly different between groups (66.3% five-day, 69.4% fourteen-day, p = 0.852). Fourteen-day cultures had a significantly longer time-to-positive culture (5.0 days) than five-day cultures (3.0 days, p < 0.001), a higher rate of fungi (5.6% vs. 0%), and a lower rate of Gram-negatives (4.5% vs. 18.7%, p = 0.016). Conclusions: Fourteen-day cultures did not increase the positivity rate, had higher rates of slow-growth pathogens, and had a longer time-to-positivization than five-day cultures. Prolonged culture holds may provide more thorough organism detection for PJI without increasing the diagnostic culture yield.

Comparison of Time and Rate of Achieving Minimal Clinically Important Difference: Robotic Versus Manual Unicompartmental Knee Arthroplasty

BACKGROUND

Robotics in unicompartmental knee arthroplasty (UKA) continues to increase with the ever-growing demand to use technology in the surgical setting. However, no studies have used minimal clinically important difference (MCID) to compare patient-reported outcome measures (PROMs) between robotic UKA (rUKA) and manual UKA (mUKA). This study aimed to compare the rate of achieving MCID for improvement (MCID-I) and worsening (MCID-W) and the time to achieving MCID.

METHODS

We conducted a retrospective analysis of robotic and manual UKAs performed between 2016 and 2022. Preoperative and postoperative Patient-Reported Outcomes Measurement Information System (PROMIS) Global Physical, PROMIS Physical Function Short-Form 10a (PF-10a), and Knee Injury and Osteoarthritis Outcome Score-Physical Function Short-Form (KOOS-PS) scores were collected. Patients were stratified on reaching MCID-I, MCID-W, or "no notable change" (score between MCID-W and MCID-I). Survival curves with and without interval censoring were used to assess the time to achieving the MCID. Log-rank and weighted log-rank tests were used to compare groups.

RESULTS

A total of 256 UKAs (64 robotic and 192 manual) were analyzed. No differences were observed in the proportion of patients achieving MCID-I or MCID-W across all three PROMs. Similarly, median time to achieving MCID showed no significant differences between rUKA and mUKA for PROMIS Global Physical (3.3 versus 4.9 months, P = 0.44), PROMIS PF-10a (7.7 versus 8.3 months, P = 0.93), and KOOS-PS (3.0 versus 6.0 months, P = 0.055) scores, both with and without interval censoring.

DISCUSSION

This study indicates that rUKA and mUKA exhibit comparable rates of achieving MCID-I and MCID-W, along with similar median time to reach MCID. These findings offer valuable patient-centric insights into the effectiveness of rUKA. Additional studies evaluating the long-term outcomes of rUKA are needed to determine its long-term advantages.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Opioid exit plans for tapering postoperative pain control in noncancer patients: a systematic review

BACKGROUND

A growing number of countries have reported sharp increases in the use and harm of opioid analgesics. High rates of new opioid initiation are observed in postoperative patients. In response, various tertiary care institutions have developed opioid exit plans (OEPs) to curb potential opioid-related harm.

METHODS

PubMed and Embase were systematically searched to identify, summarize, and compare the interventional elements of OEPs for postoperative patient populations published from January 1, 2000, to June 4, 2024. Two researchers independently screened the articles for eligibility following the PRISMA 2020 guidelines, extracted the data, and assessed the study quality and risk of bias. Data synthesis was performed for study characteristics, intervention details, efficacy, and development.

RESULTS

A total of 2,585 articles were screened, eight of which met the eligibility criteria. All studies were conducted in North America and focused on orthopedic surgery patients following total hip or knee arthroplasty (n = 5) or neurosurgery (n = 3). Most studies (n = 7) included a pre-post (n = 4) or randomized clinical design (n = 3). Three studies were of good quality, and none had a low risk of bias. The interventions varied and ranged from educational sessions (n = 1) to individualized tapering protocols (n = 4) or a combination of the two (n = 2). Key elements were instructions on how to anticipate patients' postoperative need for opioid analgesics and tapering strategies based on 24-h predischarge opioid consumption. Six studies included efficacy as an endpoint in their analysis, of which four assessed statistical significance, with all four identifying that the OEPs were successful in reducing postoperative opioid use.

CONCLUSION

Despite differences in design and implementation, the identified OEPs suggest that they are efficacious in reducing outpatient opioid consumption. They provide a robust estimate of postoperative analgesic requirements and a rationale for tapering duration and rate. However, more rigorous studies are needed to evaluate their real-world effectiveness.

Knee fusion versus above knee amputation as two options to deal with knee periprosthetic joint infection

BACKGROUND

Periprosthetic joint infection (PJI) poses a significant challenge in total knee arthroplasty (TKA), with recurrence rates as high as 14-28%, leading to substantial morbidity and treatment costs. When conventional treatments fail, knee fusion and above-the-knee amputation (AKA) emerge as alternative options. Existing literature offers conflicting views on the efficacy and impact of knee fusion versus AKA with varied outcomes and limitations.

METHODS

This retrospective national study spanning 2010-2022 investigates Knee Fusion and AKA as options for addressing Knee PJI. Utilizing PearlDiver Patient Records Database, procedural, and reimbursement data on over 100 million individuals from all the US was evaluated. Readmission rates, costs, and complications of the mentioned procedures were assessed using ICD-9 and ICD-10 codes within a 90-day period and one-year post-operation. Statistical analyses, including chi-square tests and regression models, were conducted using integrated R software.

RESULTS

The study reveals a substantial escalation (p < 0.0001) in the proportion of patients opting for AKA compared to arthrodesis. While age as a demographic factor showed no significant difference, arthrodesis patients exhibited lower comorbidity scores (3.6 ± 2.9 vs. 4.6 ± 3.4, p < 0.001). Arthrodesis correlated with higher 90-day thromboembolism rates (9.2% vs. 7.3%, p < 0.001), blood transfusion requirements (23.2% vs. 14.4%, p < 0.001), and acute renal failure incidence (p = 0.008) but demonstrated lower rates of urinary tract infections (p = 0.047) and cerebrovascular accidents (p < 0.001). At 1 year, arthrodesis was associated with higher infection rates (38.7% vs. 36.4%, p < 0.001). Arthrodesis patients had significant increased 90-day and 1-year readmission rates and hospitalization costs ($12,732 vs. $18,826, p < 0.001).

CONCLUSIONS

We found higher rates of 1-year thromboembolism, infection, acute renal failure, and readmission in the arthrodesis group. AKA patients had more sepsis and cerebrovascular accidents. A patient-centered conversation is best for persistent infections and failed revision TKA. Considering the patient's quality of life, goals, and health status, this discussion should cover each procedure's risks and complications.

Enhanced Postoperative Pain Management and Mobility Following Arthroscopic Knee Surgery: A Comparative Study of Adductor Canal Block with and without IPACK Block

BACKGROUND Arthroscopic knee surgery (AKS) is minimally invasive, reducing hospital stay compared to traditional surgery, but postoperative pain remains a significant issue. This study compared the analgesic and functional outcomes following AKS following anesthesia using adductor canal block (ACB) with and without anesthesia using the interspace between the popliteal artery and posterior capsule of the knee (IPACK) block under spinal anesthesia (SA). MATERIAL AND METHODS We randomly allocated 120 patients into 3 groups: IPACK+ACB+SA for Group A (n=40), ACB+SA for Group B (n=40), and SA for Group C (n=40). The outcome was the visual analog scale (VAS) score evaluated at rest and during activity at 3 h, 6 h, 12 h, 24 h, and 48 h postoperatively, the frequency of administration of postoperative rescue analgesic, and the maximal walking distance at 24 h and 48 h postoperatively. RESULTS Compared with Group C, the VAS scores in Group A were significantly lower at 48 h postoperatively (P<0.05). There was a significant difference in the frequency of postoperative rescue analgesia use among the 3 groups (P=0.001). In a subgroup analysis of meniscus shaping under arthroscopy, the resting VAS score in Group A was lower than that in Group B and Group C at 48 h postoperatively (P<0.05). The maximum walking distance of Group A was longer than that of Group B and Group C at 24 h and 48 h postoperatively (P<0.01). CONCLUSIONS The effect of postoperative analgesia in the group receiving IPACK combined with ACB after AKS was obviously superior. In arthroscopic meniscus repair surgery, the duration of analgesia was longer, and the maximum walking distance at 48 h postoperatively was longer.

Clinical outcomes of two-stage revision arthroplasty using a spiked tibial cement spacer in infected total knee arthroplasty

PURPOSE

A tibial cement spacer (TCS) with spikes offers better initial stability than a conventional TCS and reduces spacer-related problems in two-stage revision total knee arthroplasty (R-TKA) for infection. We compared the clinical outcomes of two-stage revision arthroplasty for infected TKA using spiked TCS with that of conventional TCS.

METHODS

This retrospective cohort study included 29 patients who underwent two-stage revision arthroplasty using an articulating cement spacer and who could be followed up for at least one year. Group S comprised 14 patients using spiked TCS, whereas Group C comprised 15 patients using conventional TCS. Demographic data, the interval from first to second stage revision, motion arc, numerical rating scale (NRS), Knee Society (KS) score, serum levels of erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP), and frequency of repeating the first-stage and infection recurrence after R-TKA between the groups were analyzed.

RESULTS

No significant differences were observed in the female ratio and mean age between both groups. The mean interval between the first and second stage revision was significantly shorter in Group S than in Group C. The mean motion arc was significantly larger in Group S than in Group C. The mean NRS was significantly lower in Group S than in Group C. The mean KS score in Group S was significantly higher than that in Group C. Serum ESR and CRP levels did not differ between the groups. The frequency of repeating the first stage was lower in Group S than in Group C. However, the recurrence rate after R-TKA was higher in Group S than in Group C.

CONCLUSION

Compared with conventional TCS, spiked TCS shortened the period until R-TKA and improved pain and function levels. However, no significant difference existed in the rate of infection recurrence after R-TKA.

Comparing the Efficacy of Antiosteoporotic Drugs in Preventing Periprosthetic Bone Loss Following Total Hip Arthroplasty: A Systematic Review and Bayesian Network Meta-Analysis

BACKGROUND

Periprosthetic bone loss is a well-known phenomenon following total hip arthroplasty (THA). However, the choice of drugs for prevention remains controversial. Therefore, the aim of this study was to determine the best drug to treat periprosthetic bone loss by comparing changes in bone mineral density (BMD) at different times after THA.

METHODS

A comprehensive search of five databases and two clinical trial registration platforms was undertaken from their inception through to August 31, 2023 to identify eligible randomized controlled trials. A Bayesian network meta-analysis (NMA) was carried out for calculating the standardized mean difference (SMD) and the surface under cumulative ranking curve (SUCRA) of the BMD in calcar (Gruen zone 7) at 6 months, 12 months, and 24 months and over.

RESULTS

Twenty-nine trials involving 1427 patients and 10 different interventions were included. The results demonstrated that at 6 months, denosumab had the highest ranking (SUCRA = 0.90), followed by alendronate (SUCRA = 0.76), and zoledronate (SUCRA = 0.73). At 12 months, clodronate ranked highest (SUCRA = 0.96), followed by denosumab (SUCRA = 0.84) and teriparatide (SUCRA = 0.82). For interventions with a duration of 24 months and over, denosumab had the highest SUCRA value (SUCRA = 0.96), followed by raloxifene (SUCRA = 0.90) and zoledronate (SUCRA = 0.75).

CONCLUSION

Investigating the existing body of evidence revealed that denosumab demonstrates potential as an intervention of superior efficacy at the three specifically examined time points. However, it remains crucial to conduct further research to confirm these findings and determine the most effective treatment strategy.

Are Routine Postoperative Hemoglobin Tests Justified in All Patients Who Undergo Total Hip Arthroplasty Due to a Displaced Femoral Neck Fracture?

Background: Total hip arthroplasty (THA) is a standard treatment for a displaced femoral neck fracture in the elderly. In contemporary healthcare, there is a global shift towards fast-track treatment modalities, prioritizing early hospital discharge for patients. Consequently, routine postoperative blood tests may become redundant, offering significant time and cost savings. We aim to evaluate postoperative hemoglobin levels in trauma-related THA cases and identify patient profiles for whom these tests hold significance. Methods: A retrospective review of 176 THA procedures performed between 2018 and 2022, focusing on individuals undergoing THA for displaced femoral neck fractures. Multivariable logistic regression analysis was employed to identify factors associated with postoperative hemoglobin levels below 8.5 g/dL. Results: Of the 176 patients included, 109 (61.9%) were women and the mean age was 69.09 ± 8.13 (range 27 to 90) years. The majority of the patients underwent surgery within 48 hours of admission. The mean preoperative hemoglobin (Hb) level was 13.1 ± 1.4 g/dL, while the mean postoperative Hb level was 10.5 ± 1.2 g/dL. Only six patients (3.41%) exhibited postoperative Hb levels of ≤8.5 g/dL. No significant associations were found between postoperative Hb levels ≤ 8.5 and any demographic, surgical, or medical characteristics. Conclusions: Our findings suggest that routine postoperative blood count testing may not be necessary for most patients undergoing THA for displaced femoral neck fractures, particularly those without complications or significant comorbidities.

Dilution of humoral immunity: Results from a natural history study of healthy total knee arthroplasty patients

The incidence of prosthetic joint infection (PJI) following elective primary total knee arthroplasty (TKA) is very low but serious risk remains. To identify unknown risk factors, we completed a natural history study of IgG specific for Staphylococcus aureus antigens previously phenotyped as protective (anti-Atl) and pathogenic (anti-Isd). Twenty-five male and 25 female optimized patients 50-85 years of age and BMI 24-39 undergoing primary TKA were prospectively enrolled. Blood sampling was performed preoperatively, postoperative Day 1, and at 2, 6, and 12 weeks, to assess serum cytokine, anti-staphylococcal IgG levels and anti-tetanus toxoid IgG measured via custom Luminex assay. Clinical, demographic, and PROMIS-10 data were collected with outcomes to 2 years postop. All participants completed the study and 2-year follow-up. No patients were readmitted or noted to develop a surgical site infection or serious adverse event, and patient-reported outcomes were improved. Serology revealed a highly significant decrease in six out of eight antibody titers against specific S. aureus antigens on Day 1 (p < 0.0001), five of which normalized to preoperative levels within 2 weeks. These changes were commensurate with a decrease and recovery of anti-tetanus toxoid titers, and a 20% drop in hemoglobin 13.8 ± 1.7 at preop to 11.1 ± 1.8 mg/dL on Day 1 (p < 0.0001). After TKA, a significant decrease in humoral immunity commensurate with blood loss and hemodilution was recorded. This decrease in circulating anti-staphylococcal antibodies in the early postop period may represent a periprosthetic joint infection risk factor for patients.

Current Evidence Does Not Support the Use of Tibial Stem Extension in Total Knee Arthroplasty of Obese Patients: A Systematic Review

BACKGROUND

Obesity rates have been increasing globally, leading to a higher incidence of knee osteoarthritis and a surge in primary and revision total knee arthroplasty (TKA). The debate continues on the impact of obesity on TKA success, particularly regarding the use of stemmed tibial components in obese patients. This systematic review aimed to compare the effectiveness of stemmed tibial components versus standard keeled tibial components in obese patients undergoing TKA, hypothesizing that stemmed components would yield better clinical and radiological outcomes.

METHODS

A systematic review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement guidelines. Databases including PubMed, Embase, Scopus, and Web of Science were searched from inception to December 2023. The eligibility criteria were based on the PICO framework; Participants: Patients who have obesity undergoing TKA, Intervention: stemmed TKA, Comparator: standard keeled tibial TKA, Outcome: aseptic loosening, Patient-Reported Outcome Measures (PROMs), and overall revision. Data extraction and quality assessment were performed using the Newcastle-Ottawa Scale for cohort studies and the Cochrane risk-of-bias tool for randomized trials.

RESULTS

The search yielded 470 studies, with 10 studies (42,533 knees) meeting the inclusion criteria. These studies included three randomized clinical trials and seven retrospective cohorts. The primary outcomes measured were aseptic loosening and overall revision rates, while secondary outcomes included PROMs. Results indicated mixed findings, with some studies suggesting improved outcomes with stemmed components in cases of aseptic loosening and mechanical failure, while others showed no significant difference. The PROMs did not show a significant difference between groups post-TKA. The certainty of the evidence was graded as "very low" using the Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) framework.

CONCLUSION

Current literature does not provide conclusive evidence to support the routine use of stemmed tibial components in TKA for obese patients. The decision to use stem extensions should not solely rely on the patient's obesity status. Further high-quality studies are needed to clarify the role of stemmed components in TKA for this patient population.

Unnecessary care in orthopaedic surgery

Unnecessary care, where the potential for harm exceeds the potential for benefit, is widespread in medical care. Orthopaedic surgery is no exception. This has significant implications for patient safety and health care expenditure. This narrative review explores unnecessary care in orthopaedic surgery. There is wide geographic variation in orthopaedic surgical practice that cannot be explained by differences in local patient populations. Furthermore, many orthopaedic interventions lack adequate low-bias evidence to support their use. Quantifying the size of the problem is difficult, but the economic burden and morbidity associated with unnecessary care is likely to be significant. An evidence gap, evidence-practice gap, cognitive biases, and health system factors all contribute to unnecessary care in orthopaedic surgery. Unnecessary care is harming patients and incurring high costs. Solutions include increasing awareness of the problem, aligning financial incentives to high value care and away from low value care, and demanding low bias evidence where none exists.

The Role of Risk Tolerance in a Patient's Decision to Undergo Total Knee and Hip Arthroplasty

BACKGROUND

A patient's decision-making process to undergo surgery is crucial for surgeons to understand for patient counseling purposes. Total knee and hip arthroplasty, like any other major surgery, is associated with serious, sometimes life-threatening, complications. Using the results of discrete choice experiments (DCE), we aimed to understand the relationship between a patient's risk tolerance and choosing to undergo surgery in real life.

METHODS

This is a retrospective study of prospectively collected DCE results for 142 potential knee or hip arthroplasty clinic patients from October 2021 to March 2022. The DCE presented the patient with two scenarios, each of which was made up of different combinations of attributes and levels. A hierarchal Bayesian model was utilized to obtain a risk score that reflected the risk attributes chosen by each patient. Logistic regressions were then utilized to evaluate the association between a patient's willingness to incur risk and their decision to undergo a total joint arthroplasty (TJA).

RESULTS

Out of the 142 patients enrolled in the DCE, 89 (62.3%) underwent a TJA. Risk score (OR [odds ratio] = 2.6, 95% CI [confidence interval] 1.1 to 6.6, P = 0.0400), men (OR = 2.5, 95% CI 1.1 to 5.9, P = 0.0280), and patients who have hip osteoarthritis (OR = 2.4, 95% CI 1.1 to 5.5, P = 0.0360) increased the odds of undergoing arthroplasty, whereas physical function of at least 75% at the initial visit (OR = 0.3, 95% CI 0.1 to 0.7, P = 0.0040) decreased these odds.

CONCLUSIONS

We found that a patient's willingness to incur risk, lower baseline physical function, and men were all independently associated with undergoing total knee arthroplasty. We believe that these findings prompt much-needed future studies that focus solely on the relationship between patients inherent risk behavior and surgical and patient-reported outcomes.

Comparison of robotic-assisted total knee arthroplasty: an updated systematic review and meta-analysis

This study was conducted to compare the changes in different clinical scores and imaging indexes of patients who underwent robot-assisted total knee arthroplasty (RA-TKA) and manual total knee arthroplasty (M-TKA). PubMed, Web of Science, Cochrane Library and Embase were searched according to PRISMA guidelines in June 2024. Search terms included "robot-assisted", "manual" and "total knee arthroplasty". Outcome indicators included American Knee Society Score (KSS), Western Ontario McMaster Universities Osteoarthritis Index (WOMAC), Oxford Knee Score (OKS), range of motion (ROM), Hospital for Special Surgery (HSS) score, Forgotten Joint Score (FJS), 36-Item Short Form Health Survey (SF-36), operation duration (min), intraoperative blood loss (ml), pain score, patient's satisfaction scores, hip-knee-ankle (HKA) angle, frontal femoral component angle, frontal tibia component angle, lateral femoral component angle and lateral tibia component angle. A total of 1,033 articles were obtained after removing duplicates, and 12 studies involving 2,863 patients (1,449 RA-TKAs and 1,414 M-TKAs) were finally meta-analyzed (22-32). The baseline data of both groups were similar in all results. Meta-analysis suggested a better performance of the RA-TKA group than the M-TKA group regarding the HKA angle. The manual TKA reduced the operation time and significantly improved the range of motion. The results of > 6 months follow-up showed that M-TKA was better than RA-TKA in terms of KSS score and WOMAC. Compared with M-TKA, RA-TKA can produce more accurate prosthetic alignment, but it does not lead to better clinical results. Orthopedic surgeons should choose between two surgical procedures according to their own experience and patients' characteristics.

Assessing extremely negative online patient reviews and complaints of musculoskeletal oncology surgeons in the United States: a retrospective analysis

INTRODUCTION

Physician-review websites (PRWs) are commonly used by patients while searching for a surgeon. There is no current literature investigating the factors that contribute to online one-star reviews of musculoskeletal oncology surgeons. This retrospective study aims to identify these factors to determine areas of care affecting patient's subjective reviews.

METHODS

Patient ratings and comments regarding musculoskeletal oncology surgeons from the Musculoskeletal Tumor Society (MSTS) were collected from Vitals.com. One-star reviews with comments were then classified as either operative or nonoperative. These complaints were then further classified based on content including wait time, uncontrolled pain, time spent with the physician, surgical outcomes, medical staff/institutional complaints, and bedside manner.

RESULTS

A total of 169 reviews (375 complaints) from 181 physicians were included. Of these complaints, 198 were from patients in the operative category while 177 were from patients in the nonoperative category. Bedside manner was the most common complaint. Operative patients reported higher instances of uncontrolled pain in their reviews, whereas nonoperative patients more frequently cited wait time. No significant difference in the complaints that mentioned the amount of time spent with the physician, bedside manner, a disagreement with the plan, or the medical staff or institution was found.

CONCLUSION

Online one-star reviews of musculoskeletal oncology surgeons on Vitals.com referenced both surgical and non-surgical aspects of patient encounters, with bedside manner being the most popular complaint overall. Surgical patients were more likely to complain of uncontrolled pain whereas non-operative patients were more likely to complain of wait time.

TYPE OF STUDY

Outcomes 2c.

Perioperative Dexamethasone Split Between Two Doses Further Reduced Early Postoperative Nausea and Vomiting Than Single Dose Dexamethasone: A Randomized Blinded Placebo-Controlled Trial

OBJECTIVE

We investigated whether two perioperative doses of dexamethasone are more effective than a single dose in reducing early postoperative nausea and vomiting (PONV) during total knee arthroplasty (TKA).

METHODS

A total of 150 patients between June 1, 2021 and June 1, 2022 were randomized into three groups: two doses of normal saline (group A); a single dose of 10 mg dexamethasone before surgery and normal saline after surgery (group B); and two doses of 5 mg dexamethasone during the perioperative period (group C). Primary outcomes were incidences and severity of PONV within 24 hours after surgery; the number of patients requiring and the consumption of morphine and metoclopramine; and VAS scores for nausea and vomiting at 2, 4, 6, and 24 hours after surgery. Blood glucose levels on days 1, 2, and 3 after operation and incidences of surgical site infection (SSI) as well as gastrointestinal bleeding (GIB) within 45 days after operation were compared.

RESULTS

Within 24 hours after operation, the number of patients requiring and the amount of consumption of morphine and metoclopramide in groups B and C were significantly lower than those in group A, however, differences between groups B and C were insignificant (P > 0.05). Incidences and severity of PONV in groups B and C were significantly lower than those in group A, and differences between groups B and C were also significant (P < 0.05). At 2, 4, 6, and 24 hours after operation, there were significant differences in visual analogue scale (VAS) scores of PONV between groups A and B, A and C, as well as B and C. On postoperative days 1, 2, and 3, there were no significant differences in blood glucose levels among the groups, and there were no incidences of SSI or GIB in any group within 45 days after operation.

CONCLUSION

Dexamethasone significantly reduces PONV within 24 hours after TKA, does not result in significant changes in postoperative blood glucose levels, and does not increase the risk of SSI as well as GIB. In addition, perioperative two-dose dexamethasone is more advantageous than single-dose dexamethasone in reducing PONV incidence and severity within 24 hours after TKA.

Titanium-Titanium Junctions in the Knee Corrode, Generating Damage Similar to the Hip

BACKGROUND

Previous studies identified corrosion between the modular tibial components of total knee arthroplasty devices. However, gaps persist. Compared to the hip, damage modes that occur within taper junctions in the knee remain poorly understood. In this study, we investigated corrosion on total knee arthroplasty components with titanium-titanium junctions. We asked the following question: under typical in vivo cyclic loading conditions, will the same alloy damage modes from total knee arthroplasty devices resemble those documented in the hip?

METHODS

A total of 50 paired titanium alloy tibial baseplates and stems were collected and semiquantitatively analyzed using Goldberg corrosion scoring. To characterize damage, a subsection of moderately and severely corroded components was sectioned and imaged using scanning electron and digital optical microscopy.

RESULTS

Of the 100 device components, 95% showed visual evidence of corrosion. The initial contact area between the stem and bore generally occurred 3 mm from the stem taper base. Scanning electron microscopy revealed 4 damage modes, including oxide film formation, crevice corrosion, selective dissolution, and pitting.

CONCLUSIONS

Each of the damage modes identified in modular titanium-titanium tibial junctions was previously reported by total hip arthroplasty retrieval studies. Cumulatively, our results suggest that mechanically assisted crevice corrosion promoted this damage in vivo.

Cobalt Serum Level as a Biomarker of Cause-Specific Survival among Prostate Cancer Patients

Prostate cancer is the most common cancer diagnosed in men and the second leading cause of death in male cancer patients. The WHO suggests that cobalt is involved in the carcinogenesis of prostate cancer. There are, however, no studies associating cobalt levels and prostate cancer patient survival. In this study, 261 Polish prostate cancer (n = 261) patients were recruited into a prospective cohort between 2009 and 2015. Serum cobalt levels were measured using ICP-MS after prostate cancer diagnosis and before treatment. All study participants were assigned into quartiles (QI-QIV) based on the distribution of serum cobalt levels among censored patients. Univariable and multivariable COX regression models were used to calculate hazard ratios (HRs) for each serum cobalt level quartile. We found a significant relationship between high serum cobalt levels and poor prostate cancer patient total survival (HR = 2.60; 95% CI: 1.17-5.82; p = 0.02). In relation to prostate cancer patients who died as a result of other non-cancer causes, the association with high levels of cobalt was even stronger (HR = 3.67; 95% CI: 1.03-13.00; p = 0.04). The impact of high serum cobalt levels on overall survival of prostate cancer-specific-related deaths was not statistically significant.

Outpatient Total Joint Arthroplasty in the "Unhealthy": Staying Safe Using Institutional Protocols

BACKGROUND

Recent expansion in the indications for outpatient total joint arthroplasty has led to debates over patient selection. The purpose of this study was to compare early clinical outcomes and complications of same-day discharge (SDD) hip and knee arthroplasties from a high-volume institution based on the American Society of Anesthesiologists (ASA) physical status classification.

METHODS

Prospectively collected data were reviewed for all SDD primary joint arthroplasties between January 2013 and August 2023. There were 8 surgeons who performed 7,258 cases at hospital outpatient (n = 4,288) or ambulatory surgery centers (n = 2,970). This included 3,239 total hip arthroplasties, 1,503 total knee arthroplasties, and 2,516 unicompartmental knee arthroplasties. The ASA 1 group comprised 506 subjects, compared to 5,005 for ASA 2 and 1,736 for ASA 3. The primary outcomes included emergency department (ED) visits, readmissions, complications, and revisions within 24 hours and 90 days of surgery. The ASA 3 group was older (ASA 1 = 55 versus ASA 2 = 63 versus ASA 3 = 66 years; P < .01) and had a higher body mass index (ASA 1 = 25.4 versus ASA 2 = 28.5 versus ASA 3 = 32.7; P < .01).

RESULTS

There were no differences between ASA groups in joint-related ED visits, readmissions, and complications within 24 h and 90 days of surgery (P > .05). Subjects in the ASA 3 group experienced greater 90-day revisions compared to the other groups (ASA 1 = 1 of 506, 0.2% versus ASA 2 = 15 of 5,005, 0.3% versus ASA 3 = 15 of 1,736, 0.9%; P = .01). Regarding systemic events, ASA 1 subjects experienced significantly greater 24-hour complications (8 of 506, 1.6%) and ED visits (5 of 506, 1.0%), and the ASA 3 subjects had a higher incidence of 90-day readmissions (19 of 1,736, 1.1%) compared to the other groups (P < .05). Within 24 hours of discharge, urinary retention and syncope were the most frequent complications that required additional health care utilization.

CONCLUSIONS

Medically optimized patients categorized as ASA 3 can safely undergo SDD hip and knee arthroplasty without increased risk of 24-hour or 90-day complications. Patient preference for outpatient care, reliable social support, and independent functional status are imperative for a successful outpatient program.

Archetype analysis of the spine-hip relationship identifies distinct spinopelvic profiles

INTRODUCTION

The position of the pelvis in the sagittal plane can vary considerably between different functional positions. Adapting the position of the acetabular cup in relation to the alignment between the spine and the hip of each individual, prior to prosthesis placement, can prevent the risk of prosthetic impingement. Taken individually, risk factors for unfavorable spinopelvic kinematics can be difficult to interpret when trying to precisely predict which patients are at risk. Furthermore, the use of classifications or algorithms can be complex, most often associated with limited values and often difficult to apply in current practices of risk assessment.

HYPOTHESIS

We hypothesized that the deconstruction of the data matrix including age and spinopelvic parameters (SPT, LL, PI, LF and PI-LL) correlated with the analysis of spinopelvic kinematics could be used to define an individualized hip-spine relationship.

MATERIAL AND METHOD

We applied archetypal analysis, which is a probabilistic, data-driven and unsupervised approach, to a complete phenotype cohort of 330 patients before total hip arthroplasty to define the spinopelvic profile of each individual using the spinopelvic parameters without threshold value. For each archetype, we analyzed the spinopelvic kinematics, not implemented in the creation of the archetypes.

RESULTS

An unsupervised learning method revealed seven archetypes with distinct spinopelvic kinematic profiles ranging from -8.9 ° to 13.15 ° (p = 0.0001) from standing to sitting and -5. 35 ° to -10.81 ° (p = 0.0001) from supine to standing. Archetype 1 represents the "ideal" patient (A1); young patients without spinopelvic anomaly and the least at risk of mobility anomaly. Followed by 3 archetypes without sagittal imbalance according to their lumbar lordosis and pelvic incidence, from the highest to the lowest (archetypes 2-4), archetype 4 exposing a greater risk of spinopelvic kinematic anomaly compared to others. Then 2 archetypes with sagittal imbalance: archetype 5, with an immobile pelvis in the horizontal plane from standing to sitting position in anterior tilt and archetype A6, with significant posterior pelvic tilt standing, likely compensating for the imbalance and associated with the greatest anomaly of spinopelvic kinematics. Finally, archetype 7 with the stiffest lumbar spine without sagittal imbalance and significant unfavorable kinematics from standing to sitting.

CONCLUSION

An archetypal approach to patients before hip replacement can refine diagnostic and prognostic features associated with the hip-spine relationship and reduced heterogeneity, thereby improving spinopelvic characterization. This risk stratification of spinopelvic kinematic abnormalities could make it possible to target patients who require adapted positioning or types of implants before prosthetic surgery.

LEVEL OF EVIDENCE

IV retrospective study.

Rising Costs and Diminishing Surgeon Reimbursement From Primary to Revision Total Hip and Knee Arthroplasty: An Analysis of Medicare Advantage and Commercial Insurance

BACKGROUND

Revision total joint arthroplasty (rTJA) is a resource-intensive procedure addressing failed primary total joint hip (total hip arthroplasty [THA]) and knee arthroplasty (total knee arthroplasty [TKA]). Despite predictions of increased demand, reimbursement for rTJA has not kept pace with increasing costs and may be insufficient compared with primary procedures. The study aimed to highlight the diminishing surgeon reimbursement between primary and revision THA (rTHA) and TKA.

METHODS

This study is a retrospective analysis of billing data for primary and rTHA and TKA procedures from a single institution between 2019 and 2022. Insurance claims and charges data were provided by a local affiliate of a major national carrier which includes Medicare Advantage (MA) and commercial patients. Using insurance data, the study evaluates the total surgery costs for primary and rTHA and TKA and the individual charges that make up the total surgery cost.

RESULTS

Nine hundred five patients insured by the same carrier, who underwent a primary or rTJA, were identified. Irrespective of MA or commercial insurance, the average surgery cost for a primary THA was $26,043, compared with $53,456 for rTHA. Surgeon reimbursement for primary THA was 20% ($5,323) of the total surgery cost. Despite the doubled surgery cost for rTHA, surgeon reimbursement was 10% ($5,257) of the total surgery cost. Primary TKA surgery costs were $24,489, while revision costs were $43,074. Surgeon reimbursement for primary TKA was 20% ($4,918) of the total surgery cost, while reimbursement for revision TKA was 13% ($5,560). MA reimbursement was markedly lower than commercial reimbursement for primary and revision cases.

CONCLUSION

Despite the higher total costs for rTJA, surgeon reimbursement is disproportionately diminished. The findings highlight the lack of incentive for revision cases. Surgeon reimbursement from MA and commercially insured patients for rTJA remains inadequate. This may limit patient access-to-care, leading to suboptimal outcomes and increased healthcare utilization.

Artificial intelligence in total and unicompartmental knee arthroplasty

The application of Artificial intelligence (AI) and machine learning (ML) tools in total (TKA) and unicompartmental knee arthroplasty (UKA) emerges with the potential to improve patient-centered decision-making and outcome prediction in orthopedics, as ML algorithms can generate patient-specific risk models. This review aims to evaluate the potential of the application of AI/ML models in the prediction of TKA outcomes and the identification of populations at risk.An extensive search in the following databases: MEDLINE, Scopus, Cinahl, Google Scholar, and EMBASE was conducted using the PIOS approach to formulate the research question. The PRISMA guideline was used for reporting the evidence of the data extracted. A modified eight-item MINORS checklist was employed for the quality assessment. The databases were screened from the inception to June 2022.Forty-four out of the 542 initially selected articles were eligible for the data analysis; 5 further articles were identified and added to the review from the PUBMED database, for a total of 49 articles included. A total of 2,595,780 patients were identified, with an overall average age of the patients of 70.2 years ± 7.9 years old. The five most common AI/ML models identified in the selected articles were: RF, in 38.77% of studies; GBM, in 36.73% of studies; ANN in 34.7% of articles; LR, in 32.65%; SVM in 26.53% of articles.This systematic review evaluated the possible uses of AI/ML models in TKA, highlighting their potential to lead to more accurate predictions, less time-consuming data processing, and improved decision-making, all while minimizing user input bias to provide risk-based patient-specific care.

The Effect of Insurance Type on Length of Stay Following Total Knee Arthroplasty

INTRODUCTION

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

METHODS

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

RESULTS

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

CONCLUSION

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

Risk prediction of kalaemia disturbance and acute kidney injury after total knee arthroplasty: use of a machine learning algorithm

INTRODUCTION

Total knee arthroplasty (TKA) is a procedure associated with risks of electrolyte and kidney function disorders, which are rare but can lead to serious complications if not correctly identified. A routine check-up is very often carried out to assess the seric ionogram and kidney function after TKA, that rarely requires clinical intervention in the event of a disturbance. The aim of this study was to identify perioperative variables that would lead to the creation of a machine learning model predicting the risk of kalaemia disorders and/or acute kidney injury after total knee arthroplasty.

HYPOTHESIS

A predictive model could be constructed to estimate the risk of kalaemia disorders and/or acute kidney injury after total knee arthroplasty.

MATERIAL AND METHODS

This single-centre retrospective study included 774 total knee arthroplasties (TKA) operated on between January 2020 and March 2023. Twenty-five preoperative variables were incorporated into the machine learning model and filtered by a first algorithm. The most predictive variables selected were used to construct a second algorithm to define the overall risk model for postoperative kalaemia and/or acute kidney injury (K+ A). Two groups were formed of K+ A and non-K+ A patients after TKA. A univariate analysis was performed and the performance of the machine learning model was assessed by the area under the curve representing the sensitivity of the model as a function of 1 - specificity.

RESULTS

Of the 774 patients included who had undergone TKA surgery, 46 patients (5.9%) had a postoperative kalaemia disorder requiring correction and 13 patients (1.7%) had acute kidney injury, of whom 5 patients (0.6%) received vascular filling. Eight variables were included in the machine learning predictive model, including body mass index, age, presence of diabetes, operative time, lowest mean arterial pressure, Charlson score, smoking and preoperative glomerular filtration rate. Overall performance was good with an area under the curve of 0.979 [CI95% 0.938-1.02], sensitivity was 90.3% [CI95% 86.2-94.4] and specificity 89.7% [CI95% 85.5-93.8]. The tool developed to assess the risk of impaired kalaemia and/or acute kidney injury after TKA is available on https://arthrorisk.com.

CONCLUSION

The risk of kalaemia disturbance and postoperative acute kidney injury after total knee arthroplasty could be predicted by a model that identifies low-risk and high-risk patients based on eight pre- and intraoperative variables. This machine learning tool is available on a web platform accessible for everyone, easy to use and has a high predictive performance. The aim of the model was to better identify and anticipate the complications of dyskalaemia and postoperative acute kidney injury in high-risk patients. Further prospective multicentre series are needed to assess the value of a systematic postoperative biochemical work-up in the absence of risk predicted by the model.

LEVEL OF EVIDENCE

IV; retrospective study of case series.

A systematic literature review of predicting patient discharges using statistical methods and machine learning

Discharge planning is integral to patient flow as delays can lead to hospital-wide congestion. Because a structured discharge plan can reduce hospital length of stay while enhancing patient satisfaction, this topic has caught the interest of many healthcare professionals and researchers. Predicting discharge outcomes, such as destination and time, is crucial in discharge planning by helping healthcare providers anticipate patient needs and resource requirements. This article examines the literature on the prediction of various discharge outcomes. Our review discovered papers that explore the use of prediction models to forecast the time, volume, and destination of discharged patients. Of the 101 reviewed papers, 49.5% looked at the prediction with machine learning tools, and 50.5% focused on prediction with statistical methods. The fact that knowing discharge outcomes in advance affects operational, tactical, medical, and administrative aspects is a frequent theme in the papers studied. Furthermore, conducting system-wide optimization, predicting the time and destination of patients after discharge, and addressing the primary causes of discharge delay in the process are among the recommendations for further research in this field.

Enhancing Pathogen Detection in Implant-Related Infections through Chemical Antibiofilm Strategies: A Comprehensive Review

Implant-related infections (IRIs) represent a significant challenge to modern surgery. The occurrence of these infections is due to the ability of pathogens to aggregate and form biofilms, which presents a challenge to both the diagnosis and subsequent treatment of the infection. Biofilms provide pathogens with protection from the host immune response and antibiotics, making detection difficult and complicating both single-stage and two-stage revision procedures. This narrative review examines advanced chemical antibiofilm techniques with the aim of improving the detection and identification of pathogens in IRIs. The articles included in this review were selected from databases such as PubMed, Scopus, MDPI and SpringerLink, which focus on recent studies evaluating the efficacy and enhanced accuracy of microbiological sampling and culture following the use of chemical antibiofilm. Although promising results have been achieved with the successful application of some antibiofilm chemical pre-treatment methods, mainly in orthopedics and in cardiovascular surgery, further research is required to optimize and expand their routine use in the clinical setting. This is necessary to ensure their safety, efficacy and integration into diagnostic protocols. Future studies should focus on standardizing these techniques and evaluating their effectiveness in large-scale clinical trials. This review emphasizes the importance of interdisciplinary collaboration in developing reliable diagnostic tools and highlights the need for innovative approaches to improve outcomes for patients undergoing both single-stage and two-stage revision surgery for implant-related infections.

Fixed-Bearing Lateral Unicompartment Knee Arthroplasty in Degenerative ACL-Deficient and ACL-Intact Knees: A Matched Pair Analysis

BACKGROUND

Anterior cruciate ligament (ACL)-deficient knees are no longer considered a contra-indication for unicompartment knee arthroplasty (UKA). The purpose of this study was to determine if patients who had an ACL-deficient knee who underwent lateral UKA had similar mean 10-year outcomes compared to patients who had an ACL-intact knee and lateral UKA.

METHODS

Patients who underwent a lateral UKA with ACL deficiency by a single surgeon between 2004 and 2016 were identified. Preoperative magnetic resonance images were utilized to identify a torn or absent ACL in all knees. The absence of an ACL was confirmed during arthroscopy prior to UKA. Patients were matched 1:2 based on age and sex with patients who underwent lateral UKA with an ACL intact knee. The primary patient-reported outcome variable was survival without conversion to total knee arthroplasty. Secondary outcomes included Veterans Rand-12, the Lysholm score, the Knee Osteoarthritis Outcome Score activities of daily living subscale, and Sport subscale. A power analysis showed that 14 patients were needed to identify differences of 10 points on the Knee Osteoarthritis Outcome Score with a power of 80% (P = .05).

RESULTS

The cohort of patients who had an ACL-deficient lateral UKA included 4 men and 12 women (43 to 82 years of age). The matched control group included 32 patients. The mean age of both groups was 67 years (range, 43 to 85). There were 2 patients in the ACL-deficient group who failed. At 10 years, survivorship in the ACL-deficient group was 85%, while survival in the ACL-intact group was 100% (P = .035). At an average follow-up of 11 years (range, 4 to 19.6), there was no difference in outcome scores between ACL-deficient and ACL-intact patients.

CONCLUSION

Fixed-bearing lateral UKA in the ACL-deficient knee resulted in lower survival than patients who had an intact ACL. Patient-reported outcomes were similar in both groups. The ACL-deficient patient who wishes to undergo lateral UKA should be counseled on the lower survival.

LEVEL OF EVIDENCE

Level III. Retrospective cohort study.

Gender differences in unintended anterior pelvic roll during primary THA in the lateral position

BACKGROUND

Fundamental morphologic differences between male and female pelvises are historically recognised. Despite this, little consideration has been given as to whether or not conventional positioning supports used for primary total hip arthroplasties (THAs) performed in the lateral position do an equally effective job of maintaining the intended set up position when comparing genders. Given that recent research has highlighted that unintended pelvic roll occurs commonly during hip surgery, and that such movement may have a mechanically-deleterious consequence upon final construct performance and complication rates, this study was undertaken to explore the differences in pelvic roll between genders.

METHODS

The output of a high-precision, commercially-available, imageless intra-operative navigation system was prospectively-collected for 85 consecutive patients undergoing unilateral, primary THAs. These data were separated by gender and were utilised to determine differences in pelvic movement around a central sagittal axis.

RESULTS

Demographic data were similar between genders, with no between-group differences in mean BMI (p = 0.09) or indication for surgery (p = 0.66), however participating males (mean 68.04) were slightly younger than females (mean 73.31). The mean anterior pelvic roll for females was 9.50°, and for males 8.68°. There were no statistically significant independent correlations observed between gender (p = 0.21) and pelvic roll.

CONCLUSION

The findings of this novel study do not suggest gender differences in the magnitude of unintended, intra-operative, anterior roll, even when corrected for BMI and surgical indication. Average roll of ~ 9° was demonstrated across both groups. An awareness of such positional change during THA surgery may reduce potentially-avoidable post-operative complications.

Peri-operative zoledronic acid attenuates peri-prosthetic osteolysis in a rat model of cemented knee replacement

Progressive osteolysis can occur at the cement-bone interface of joint replacements and the associated loss of fixation can lead to clinical loosening. We previously developed a rat hemiarthroplasty model that exhibited progressive loss of fixation with the development of cement-bone gaps under the tibial tray that mimicked patterns found in human arthroplasty retrievals. Here we explored the ability of a bisphosphonate (zoledronic acid, ZA) to attenuate cement-bone osteolysis and maintain implant stability. Sprague-Dawley rats (n = 59) received a poly(methylmethacrylate) cemented tibial component and were followed for up to 12 weeks. Treatment groups included peri-operative administration of ZA (ZA group), administration of ZA at 6 weeks postop (late ZA group), or vehicle (Veh group). There was a 60% reduction in the rate of cement-bone gap formation for the ZA group (0.15 mm3/week) compared to Veh group (0.38 mm3/week, p = 0.016). Late ZA prevented further progression of gap formation but did not reverse bone loss to the level achieved in the ZA group. Micromotion from five times body weight toggle loading was positively correlated with cement-bone gap volume (p = 0.009) and negatively correlated with the amount of cement in the metaphysis (p = 0.005). Reduced new bone formation and enduring nonviable bone in the epiphysis for the ZA group were found. This suggests that low bone turnover in the epiphysis may suppress the early catabolic response due to implantation, thereby maintaining better fixation in the epiphysis. This preclinical model presents compelling supporting data documenting improved maintenance of the cement-bone fixation with the use of peri-operative bisphosphonates.

No increased risk of postoperative adverse events in patients with hidradenitis suppurativa following a total joint replacement

There is concern for increased risk of adverse events, particularly periprosthetic joint infection (PJI), following total joint replacement (TJR) in patients with hidradenitis suppurativa (HS) because of a compromised skin barrier and bacterial colonization of lesions. We used the TriNetX health research database to identify patients who had undergone TJR with (n = 1760) and without (n = 1760) HS matched by age, sex, ethnicity, race and risk factors for PJI. Multivariate analysis was performed and revealed that 90-day risk of PJI, reoperation, wound dehiscence, delayed wound healing, emergency room visits and readmission were not increased among patients with HS who underwent TJR. Given these findings, dermatologists and orthopaedists should not defer TJR access for patients with HS, as risk of postoperative complications is not prohibitive.

Postoperative Complications and Readmission Rates in Robotic-Assisted Versus Manual Total Knee Arthroplasty: Large, Propensity Score-Matched Patient Cohorts

INTRODUCTION

There is a paucity of research comparing postoperative complication rates between manual total knee arthroplasty (M-TKA) and robotic-assisted total knee arthroplasty (RA-TKA). This study aims to compare 90-day postoperative complication, readmission, and emergency department rates between RA-TKA and M-TKA.

METHODS

A retrospective review of a multihospital database identified patients who underwent TKA between January 2016 and May 2023. Surgeons who used the robotic-assisted surgery technique in <10% or >90% of their cases annually were excluded. This resulted in 15,999 cases (8,853 RA-TKAs; 7,146 M-TKAs) from 282 surgeons. RA-TKA and M-TKA cohorts were one-to-one matched based on patient sex, age, body mass index, hospital setting, surgeon experience, primary payer, and anesthesia type. Each cohort consisted of 7,146 patients (N = 14,292). 90-day revisits, specifically readmissions, readmissions with >23 hours of observation, and ED visit rates were compared between cohorts. Complications were classified according to the Clinical Classification Software schema and compared between cohorts. Mann-Whitney U, chi-squared, and Fisher exact tests, along with Bonferroni correction, were used to statistically compare cohorts.

RESULTS

All-cause 90-day readmission rates were 2.4% for RA-TKA and 2.6% for M-TKA (P = 0.36). RA-TKA had fewer revisits (RA-TKA: 7.8%; M-TKA: 8.8%, P = 0.027) and rates of readmission with >23 hours of observation (RA-TKA: 1.4%; M-TKA: 2.0%, P = 0.003). RA-TKA had fewer hospital revisits due to joint stiffness (RA-TKA: 17 revisits; M-TKA: 42 revisits, P = 0.002) and chronic pain (RA-TKA: 1 revisit; M-TKA: 8 revisits, P = 0.039). Fewer readmissions were observed for acute injuries (lower extremity muscle/tendon strains) in the RA-TKA cohort (RA-TKA: 1; M-TKA: 9, P = 0.021). RA-TKA had fewer ED visits due to hematomas (RA-TKA: 0 visits; M-TKA: 7 visits, P = 0.016).

CONCLUSION

In this retrospective matched cohort analysis, RA-TKA was associated with markedly fewer revisits and readmissions with >23 hours of observation compared with M-TKA. No differences in all-cause 90-day readmission were observed between cohorts.

LEVEL OF EVIDENCE

Level III.

STUDY DESIGN

Retrospective review.

Advanced Multi-Layer Watertight Closure versus Conventional Closure in Total Hip and Knee Replacement Surgery

Background

In total joint replacement procedures, surgeons have increasingly adopted advanced multi-layer, watertight closure. The objective of the study was to compare the clinical and economic outcomes for advanced multi-layer, watertight closure patients to those with conventional closure with sutures and skin staples.

Methods

Patients aged ≥18 years were included in the study if they underwent total joint arthroplasty of the hip or knee as an elective, primary, inpatient procedure between January 2014 and March 2019. Cohorts having advanced multi-layer, watertight closure or conventional closure were compared using multivariable regression analysis of surgical site infections, length of stay, operating room time, procedure time, discharge status, readmissions, reoperations, and hospital emergency department visits.

Results

A total of 1828 patients received at least one total hip or knee replacement, of which 434 (23.7%) had advanced multi-layer, watertight closure and 1394 (76.3%) had conventional closure. Unadjusted time to readmission, when occurring, was considerably longer following advanced multi-layer, watertight closure (89.9 vs 51.1 days, p < 0.0001), and a lower proportion of the advanced multi-layer, watertight closure cohort required reoperation within 90 days (0.0% vs 2.6%, p < 0.0001). Adjusted mean hospital length of stay was approximately half of a day shorter for advanced multi-layer, watertight closure patients (1.10 vs 1.65 days; p < 0.001), and they were also more likely to be discharged to home (Odds Ratio: 4.61; p = 0.002).

Conclusion

Among patients undergoing total hip and knee arthroplasty in a highly optimized real-world clinical practice, advanced multi-layer, watertight closure was associated with significantly shorter inpatient length of stay and increased likelihood of being discharged to home compared with conventional closure. These findings suggest that advanced multi-layer, watertight closure is a valuable component of an optimal workflow for total hip or knee replacement, and may be especially valuable for high-risk patients.

Understanding the value of rehabilitation: Perspectives from South African Stakeholders

Background

The need for rehabilitation in South Africa has doubled between 1990 and 2017 and is expected to increase in the coming years. However, the rehabilitation needs of South Africans (and globally) remain largely unmet. Establishing a common understanding of the value of rehabilitation can inform clinical practice and policymaking to achieve Universal Health Coverage (UHC).

Objectives

This study aims to explore the value of rehabilitation services in South Africa's public healthcare sector by gathering perspectives from stakeholders. The goal is to inform policy decisions related to the implementation of National Health Insurance (NHI) in South Africa.

Method

The study used a phenomenological approach and interpretivist paradigm. Semi-structured interviews were conducted face-to-face, online, or telephonically with 12 stakeholders from various rehabilitation sectors. The value of rehabilitation was analysed and categorised into five main categories: context, service delivery, patient outcomes, economic and financial components, and collaboration within and between sectors.

Results

The value of rehabilitation was found to be multifaceted, because of the varying health, economic, and social challenges faced by many South Africans.

Conclusion

The study identified components of value-based rehabilitation that should be prioritised in the proposed NHI of South Africa. Future research should explore all stakeholder perspectives, including patients, and provide empirical evidence of rehabilitation's economic and societal value.

Contribution

We highlight priority areas that are central to the value of rehabilitation in South Africa and other low- and middle-income countries (LMICs). Tailoring rehabilitation services to patient and community needs is crucial for achieving value-based care. Given South Africa's commitment to the United Nations Convention on the Rights of Persons with Disabilities, prioritising rehabilitation remains essential.

Simple Hip Value: a simple score to evaluate Hip function

BACKGROUND

Several self-administered questionnaires are available for assessing hip function in clinical practice (HOOS-12, Oxford-12). These questionnaires can be used to assess and monitor patients with hip pathology. However, they are sometimes difficult to deploy in clinical practice. Recent studies on the shoulder and knee have shown that a single-question assessment provides a relevant evaluation of joint function, and correlates with more complex scores. However, this has not yet been evaluated for the hip. We set out to develop a single-question test that would enable patients to assess their hip function between 0 and 100. Therefore, we did a prospective study aiming to assess: (1) the relevance of the SHV (Simple Hip Value) test by comparing it with the Oxford-12 and HOOS-12 scores, (2) the discriminatory capacity and reproducibility of this test.

HYPOTHESIS

The hypothesis of this study was that the assessment of hip function by a single-question patient-completed questionnaire (PROM) would be reliable and useful in clinical practice.

PATIENTS AND METHODS

We conducted a prospective study including 74 patients operated on for total hip arthroplasty from February 2020 to April 2021 in a high-volume center and 20 healthy subjects. The SHV questionnaire, as well as HOOS-12 and OXFORD-12 were submitted on average 18 months after surgery, with values scaled to 100 points. A second test containing the 3 questionnaires was resubmitted to 20 patients randomly chosen from hip arthroplasty group to evaluate the reproducibility of the test. To evaluate the discrimination capacity of our test, 20 controls were selected to respond to the three questionnaires.

RESULTS

Test results were median SHV, Oxford-12 and HOOS-12 scores of 90/100 (Interquartile Range [IQR]: 80-95), 88.5 (IQR: 77.1-95.8) and 79.1 (IQR: 65.1-93.2), respectively. The SHV was strongly correlated with the Oxford-12 (Spearman coefficient: 0.63 [IQR: 0.45-0.76]) and the HOOS-12 (Spearman coefficient: 0.66 [IQR: 0.46-0.79]). The SHV differed significantly from the control group (90.0 vs 100.0 in the control group [p < 0.001]) and had excellent reproducibility (Interclass Correlation Coefficient [ICC]: ICC: 0.82 [CI95%, 0.59-0.93]).

DISCUSSION

The SHV test seems to be a reliable, reproducible and discriminating tool for assessing hip function after total hip arthroplasty, thus offering a simplified and practical approach for practitioners. Further testing in different populations would be useful to validate this test.

LEVEL OF EVIDENCE

III; prospective comparative diagnostic study.

Tibial insert design significantly alters knee kinematics using a single cruciate-retaining total knee implant

Aims

Patient dissatisfaction is not uncommon following primary total knee arthroplasty. One proposed method to alleviate this is by improving knee kinematics. Therefore, we aimed to answer the following research question: are there significant differences in knee kinematics based on the design of the tibial insert (cruciate-retaining (CR), ultra-congruent (UC), or medial congruent (MC))?

Methods

Overall, 15 cadaveric knee joints were examined with a CR implant with three different tibial inserts (CR, UC, and MC) using an established knee joint simulator. The effects on coronal alignment, medial and lateral femoral roll back, femorotibial rotation, bony rotations (femur, tibia, and patella), and patellofemoral length ratios were determined.

Results

No statistically significant differences were found regarding coronal alignment (p = 0.087 to p = 0.832). The medial congruent insert demonstrated restricted femoral roll back (mean medial 37.57 mm; lateral 36.34 mm), while the CR insert demonstrated the greatest roll back (medial 42.21 mm; lateral 37.88 mm; p < 0.001, respectively). Femorotibial rotation was greatest with the CR insert with 2.45° (SD 4.75°), then the UC insert with 1.31° (SD 4.15°; p < 0.001), and lowest with the medial congruent insert with 0.8° (SD 4.24°; p < 0.001). The most pronounced patella shift, but lowest patellar rotation, was noted with the CR insert.

Conclusion

The MC insert demonstrated the highest level of constraint of these inserts. Femoral roll back, femorotibial rotation, and single bony rotations were lowest with the MC insert. The patella showed less shifting with the MC insert, but there was significantly increased rotation. While the medial congruent insert was found to have highest constraint, it remains uncertain if this implant recreates native knee kinematics or if this will result in improved patient satisfaction.

Risk factors of postoperative urinary retention following total hip and knee arthroplasty

Aims

The aim of this meta-analysis was to determine the pooled incidence of postoperative urinary retention (POUR) following total hip and knee arthroplasty (total joint replacement (TJR)) and to evaluate the risk factors and complications associated with POUR.

Methods

Two authors conducted searches in PubMed, Embase, Web of Science, and Scopus on TJR and urinary retention. Eligible studies that reported the rate of POUR and associated risk factors for patients undergoing TJR were included in the analysis. Patient demographic details, medical comorbidities, and postoperative outcomes and complications were separately analyzed. The effect estimates for continuous and categorical data were reported as standardized mean differences (SMDs) and odds ratios (ORs) with 95% CIs, respectively.

Results

A total of 31 studies were included in the systematic review. Of these, 29 studies entered our meta-analysis, which included 3,273 patients diagnosed with POUR and 11,583 patients without POUR following TJR. The pooled incidence of POUR was 28.06%. Demographic risk factors included male sex (OR 1.81, 95% CI 1.26 to 2.59), increasing age (SMD 0.16, 95% CI 0.04 to 0.27), and American Society of Anesthesiologists grade 3 to 4 (OR 1.39, 95% CI 1.10 to 1.77). Patients with a history of benign prostatic hyperplasia (OR 1.99, 95% CI 1.41 to 2.83) and retention (OR 3.10, 95% CI 1.58 to 6.06) were more likely to develop POUR. Surgery-related risk factors included spinal anaesthesia (OR 1.44, 95% CI 1.19 to 1.74) and postoperative epidural analgesia (OR 2.82, 95% CI 1.65 to 4.82). Total hip arthroplasty was associated with higher odds of POUR compared to total knee arthroplasty (OR 1.10, 95% CI 1.02 to 1.20). Postoperatively, POUR was associated with a longer length of stay (SMD 0.21, 95% CI 0.02 to 0.39).

Conclusion

Our meta-analysis demonstrated key risk variables for POUR following TJR, which may assist in identifying at-risk patients and direct patient-centered pathways to minimize this postoperative complication.

Discontinuing the recommendation of hip precautions does not increase the risk of early dislocation after primary total hip arthroplasty using 36-mm heads: a population-based study from the Danish Hip Arthroplasty Register

BACKGROUND AND PURPOSE

Dislocation is a severe complication following total hip arthroplasty (THA). Hip precautions have been recommended in the initial postoperative period but evidence supporting this practice is limited. We therefore conducted a population-based study to evaluate the association between discontinuing recommending postoperative hip precautions and the risk of early dislocation.

METHODS

This is a cohort study with data from the Danish Hip Arthroplasty Register and the Danish National Patient Register. We included patients who underwent primary THA for osteoarthritis in 2004-2019 in public hospitals in the Capital Region of Denmark. The cohort was divided into the hip precautions group, comprising patients operated on between 2004 and 2009, and the no-precautions group operated on between 2014 and 2019. The primary outcome was the difference in the absolute risk of dislocation within 3 months post-surgery. The secondary outcome assessed the same risk within 2 years. We evaluated the difference in absolute risk using absolute risk regression (ARR).

RESULTS

The cumulative incidence of dislocation within 3 months was 2.9% (confidence interval [CI] 2.5-3.3) in the hip precautions group and 3.5% (CI 3.1-3.9) in the no-precautions group. The risk of dislocation was higher in the no-precautions group but failed to reach statistical significance in the crude (ARR 1.2, CI 0.9-1.6) and multivariate model (ARR 1.4, CI 0.9-2.2).

CONCLUSION

We found a higher but statistically insignificant increase in the risk of early dislocation in the no-precautions group. The lack of significance in the association may be explained by the increased use of 36-mm femoral heads after the guideline revision.

Bone graft incorporation failure with inappropriate limb load transfer can lead to aseptic acetabular loosening of metal-on-metal prosthesis: A case report

BACKGROUND

Aseptic acetabular loosening can result from various factors that can be categorized into groups: patient-related, surgeon-related and implant-related. We present a case of a 63-year-old patient who at first underwent a total hip arthroplasty (THA) using a metal-on-metal bearing due to hip arthrosis. Follow-up visits revealed no complications after the procedure. Two years after the THA, acetabular component loosening occurred due to subsequent trauma of the opposite hip, necessitating a revision THA using a ceramic-on-ceramic bearing.

CASE SUMMARY

We aim to illustrate a rare case where the primary reason for undergoing THA revision was not only incomplete bone graft incorporation but also improper limb load distribution. Following the revision arthroplasty, a 9-year follow-up visit revealed improvements in all evaluation measures on questionnaire compared to the state before surgery: Harris Hip Score (before surgery: 15; after surgery: 95), Western Ontario and McMaster Universities Arthritis Index (before surgery: 96; after surgery: 0), and Visual Analogue Scale (before surgery: 10; after surgery: 1).

CONCLUSION

Opposite-hip trauma caused a weight transfer to the limb after a THA procedure. This process led to a stress shielding effect, resulting in acetabular component loosening.