Journal of Arthroplasty最新文献

Background: Periprosthetic joint infections (PJIs) of the hip and knee are a devastating outcome of arthroplasty, resulting in profound morbidity. As more arthroplasties are performed, there is a need to monitor the long-term risk and trends of infection.

Methods: A population-based retrospective cohort of all primary hip and knee arthroplasties performed in Ontario from April 1, 2003, until March 31, 2017, was created using linked administrative databases with patients followed postoperatively until March 31, 2018. There were 504,332 primary hip and knee arthroplasties performed, with the number of annual procedures increasing an average of 5.8% annually over the study. The primary outcome was hospital readmission for a PJI. Poisson models were used to determine trends over time.

Results: Overall, 7,331 PJIs were identified. The incidence of a PJI following primary arthroplasty was 0.59 out of 100 (95% confidence interval (CI): 0.57 to 0.61) at 90 days and 1.29 of 100 (95% CI: 1.26 to 1.33) at five years, whereas following revision arthroplasty, it was 1.93 of 100 (95% CI: 1.70 to 2.16) at 90 days and 4.89 of 100 (95% CI: 4.52 to 5.26) at five years. The 1-year incidence of PJI following primary arthroplasty increased from 0.70 of 100 in 2003 to 0.97 of 100 in 2016 (P < 0.001).

Conclusion: The PJIs are increasing, both because of an increase in the numbers of primary arthroplasties and due to an increase in PJIs occurring within 90 days. There is a need to understand the reasons for the rise in PJIs.

Background: Metabolic syndrome (MetS), a cluster of interrelated metabolic abnormalities typically including obesity, dyslipidemia, diabetes, and hypertension, has been linked to surgical complications, but its impact on total hip arthroplasty (THA) beyond 90 days is unclear. This study compared 90-day, one-year, and two-year THA outcomes in patients who had and did not have MetS, and identified which component of MetS (i.e., diabetes, hypertension, obesity, or hypertriglyceridemia) was most strongly associated with each complication. Outcomes included a) infectious (surgical site infection [SSI; 90-day], periprosthetic joint infection [PJI]), b) mechanical (mechanical loosening, periprosthetic fracture [PPFx]), c) all-cause revision [ACR], and d) deep vein thrombosis [DVT; 90-day].

Methods: A nationwide database identified 706,602 THA patients (21.0% MetS) from 2010 to 2023. Outcomes were evaluated at 90 days, one year, and two years. Unadjusted comparisons used Pearson's Chi-square and Student's t-tests; multivariable logistic regressions calculated odds ratios (OR) with 95% confidence intervals.

Results: Higher 90-day SSI (OR 2.41) and PJI at 90 days and at one and two years (OR 1.58, 1.44, and 1.31) were associated with MetS. Obesity was most strongly associated with infection (SSI OR 2.45; PJI OR 1.73 to 1.87), followed by diabetes (SSI OR 1.58; PJI OR 1.47 to 1.60) and hypertension (PJI OR 1.47 to 1.50). Odds of PPFx were higher at all timepoints (OR 3.35, 3.10, and 2.86) most strongly associated with hypertriglyceridemia (OR 1.27 to 1.28) and diabetes (OR 1.21 to 1.25). Odds of ACR increased (OR 2.08, 1.81, and 1.66) and were associated with hypertension (OR 1.35 to 1.41) and obesity at 90 days (OR 1.11). Increased 90-day DVT (OR 3.52) was associated with hypertension, diabetes, and obesity (OR 1.59, 1.34, and 1.31).

Conclusion: Metabolic syndrome was associated with higher odds of infection, PPFx, ACR, and DVT, suggesting that this population may benefit from focused perioperative risk assessment and optimization.

Background: Ambulatory surgery centers (ASCs) are increasingly becoming the preferred setting for elective orthopaedic procedures, including total knee arthroplasty (TKA). The ASC's favorable cost containment, reimbursements, and patient outcomes have driven their growth, but access to the Medicaid population remains an issue. This study aimed to evaluate these barriers for patients seeking TKA at ASCs compared to public hospitals using a cross-sectional survey design.

Methods: All current ASCs registered within the United States were queried, and ASCs offering orthopaedic surgery services were isolated. Trained researchers contacted ASCs and public hospitals using a standardized inquiry script. Key data points included Medicaid acceptance, appointment availability, and out-of-pocket costs. Data were analyzed utilizing chi-square and Student t-tests. A total of 98 ASCs and 98 matched public hospitals were contacted for the study (Vermont and South Dakota had one ASC meeting initial criteria), with 77 ASCs and 94 public hospitals having complete data for analyses.

Results: Public hospitals demonstrated greater Medicaid acceptance compared to ASCs (95 versus 78%, P = 0.002). Both ASCs and public hospitals offered similar appointment availability (14.4 versus 19.1 d, P = 0.258). There were no differences between ASC and hospital out-of-pocket consultation ($470 versus $200, P = 0.483) or procedure costs ($199,167 versus $28,000, P = 0.317); however, only one public hospital and six ASCs provided cost information.

Conclusions: Although ASCs and public hospitals offer comparable appointment availability for elective TKA procedures, ASCs provide much lower Medicaid acceptance rates. Despite the benefits of ASCs, barriers for Medicaid patients persist, highlighting the need for targeted strategies to enhance access to specialized orthopaedic care in the ambulatory setting.

Level of evidence: III.

Background: Total hip arthroplasty (THA) is a highly effective procedure, but outcomes may be influenced by social determinants of health. We investigated the association between neighborhood disadvantage indices, the Social Vulnerability Index (SVI) and Area Deprivation Index (ADI), and postoperative outcomes following THA in a large, multicenter cohort.

Methods: A retrospective review of 9,519 primary THAs performed between 2014 and 2022 was conducted. Patient addresses were geocoded to US Census tracts to assign SVI and ADI scores. We analyzed associations between disadvantage indices and postoperative complications, health care utilization, and patient-reported outcomes using multivariable regression models.

Results: Our analysis found that neighborhood disadvantage was associated with specific postoperative outcomes. Patients who were from higher socioeconomic disadvantage quartiles had an increased risk of periprosthetic fracture (odds ratio = 2.07; 95% confidence interval: 1.21 to 3.54). Conversely, a higher disadvantage in the housing type and transportation domain was associated with a decreased risk of 90-day readmission (odds ratio = 0.72; 95% confidence interval: 0.56 to 0.91). Higher minority status disadvantage was associated with a significant decrease in lengths of hospital stay. There were no significant associations observed for overall SVI or ADI with most outcomes, and long-term improvements in patient-reported outcome measures were similar across all disadvantage levels.

Conclusions: The findings indicate that certain subdomains of neighborhood-level social disadvantage are linked to specific adverse events and health care utilization in THA patients. These associations highlight the need for tailored interventions to mitigate risks in vulnerable populations. While functional outcomes remain consistent, targeted support for patients who have high socioeconomic disadvantage may reduce complications like periprosthetic fractures. Further research is needed to better understand the mechanisms behind these associations and to develop effective, individualized care pathways.

Background: In an era of value-based medical management, anemia optimization before revision total knee arthroplasty (TKA) could improve outcomes. Using a simulation model, we evaluated whether outcomes would improve for revision TKA if patients were either approved/denied surgery based on incremental preoperative anemia thresholds.

Methods: We retrospectively reviewed consecutive revision TKA patients from 2019 to 2024. Exclusion criteria were primary TKA, no preoperative hematocrit, and incomplete 1-year follow-up. Simulated preoperative hematocrit cutoff values of 39 to 33% were used in a sequential manner. Preoperative hematocrit values above each threshold "met the threshold" for surgery, while hematocrit values below each threshold "did not meet the threshold" for surgery. Intraoperative transfusion, postoperative transfusion, discharge disposition, 90-day readmission, and complications were evaluated. Area under the curve (AUC) determined anemia thresholds needed for an event not to occur.

Results: If the strictest 39% hematocrit threshold was used, 669 of 1,322 (50.6%) patients would not meet the threshold for surgery, with these patients having higher readmissions (18.2 versus 8.4%), intraoperative transfusions (13 versus 0.5%), postoperative transfusions (26.3 versus 4.1%), nonhome discharge (53.8 versus 23.7%), and postoperative complications (26.8 versus 10.6%) compared to counterparts meeting the threshold. If the most lenient 33% hematocrit threshold was used, 243 of 1,322 (18.4%) patients would not meet the threshold for surgery, with higher readmissions (23.9 versus 11%), intraoperative transfusions (31.7 versus 1.2%), postoperative transfusions (50.2 versus 7.5%), nonhome discharge (74.5 versus 31%), and postoperative complications (38.7 versus 14.3%) compared to counterparts meeting the threshold. Based on area under the curve testing, the most sensitive and specific hematocrit threshold was 33.3% for intraoperative transfusion (sensitivity 86.1%, specificity 87.8%). Similar trends were found across hemoglobin thresholds.

Conclusions: Setting preoperative anemia thresholds for revision TKA eligibility may have a role in reducing the likelihood of readmission, transfusion, complications, and nonhome discharge. Preoperative hematocrit thresholds consistently demonstrated high sensitivity and positive predictive value pertaining to intra- and postoperative transfusion rates. Optimization of these thresholds, when possible, may improve the likelihood of a successful outcome and maximize value-based care.

Background: Total hip arthroplasty (THA) is increasingly performed in patients younger than 20 years who have destructive hip pathology. The unique anatomical and developmental characteristics of this population, along with the high likelihood of future revision surgery, have led to cautious clinical decision-making. Data on safety, effectiveness, and long-term (20-year) outcomes in teenagers remain limited. This study aimed to evaluate implant survival, patient satisfaction, functional outcomes, and complications following THA in teenagers.

Methods: This retrospective cohort study with cross-sectional evaluation was conducted at a tertiary academic center. All patients aged 10 to 19 at the time of surgery with ≥ one year follow-up were included. The study population comprised 68 teenagers (75 THAs), who had a median age at surgery of 16 years (range, 11 to 19). The median follow-up was 5.4 years (range, 1.0 to 20.4). The most common indications were developmental dysplasia of the hip (28%), slipped capital femoral epiphysis (20%), and osteonecrosis (17.3%). Of the 75 hips, 37 (49%) had undergone prior hip-preserving procedures. Implant survival was assessed using Kaplan-Meier analysis, with revision as the primary endpoint. Additionally, Hip disability and Osteoarthritis Outcome Score for Physical Function (HOOS-PS; 0 to 100) and patient satisfaction (Likert scale; 1 to 10) were assessed. Pre- and postoperative pain and mobility were extracted from patient records.

Results: There were five reoperations (6.7%), of which four revisions were treated, corresponding to a 5-year survival of 94.2% (95% confidence interval (CI): 82.7 to 98.2). With a 10- and 15-year survival of 90.1% (95% CI: 73.9 to 96.5). At follow-up, 96% of respondents rated their hip prosthesis as satisfactory (Likert scale ≥ 6 out of 10). There was one postoperative wound infection successfully treated with irrigation and antibiotics. The HOOS-PS score was 15.1 (range, 0 to 50.8). Postoperative pain and mobility demonstrated statistically significant improvement (P < 0.001).

Conclusion: This study demonstrates good implant survival at follow-up and high satisfaction rates in teenagers following THA, representing, to our knowledge, the first standardized cross-sectional evaluation of satisfaction in this population.

Background: While testosterone replacement therapy (TRT) is known to affect cardiovascular physiology, its impact on outcomes following total hip arthroplasty (THA) remains unclear. This study aimed to assess whether preoperative TRT use is associated with increased complications following THA.

Methods: A retrospective cohort study using a large national database was performed. Adult patients undergoing primary THA before February 2020 with 5-year follow-up were stratified based on preoperative TRT use within one year of surgery. Patients who had a history of septic arthritis, osteonecrosis, or pathologic fractures were excluded. Propensity score matching (1:1) was used to balance cohorts. Outcomes included medical complications at 90 days and one year and prosthetic complications up to five years postoperatively. Following matching, 3,953 patients were included in each cohort.

Results: At 90 days, TRT use was associated with higher rates of deep vein thrombosis (2.8 versus 2.0%; P = 0.023), pneumonia (3.2 versus 1.7%; P < 0.001), and sepsis (4.2 versus 0.9%; P < 0.001). At one year, TRT users had increased rates of deep vein thrombosis (4.3 versus 3.0%; P = 0.002), cardiac events (2.9 versus 1.7%; P < 0.001), pneumonia (6.1 versus 3.4%; P < 0.001), acute kidney injury (7.6 versus 5.6%; P < 0.001), and sepsis (3.8 versus 1.9%; P < 0.001). At five years, TRT users had higher rates of periprosthetic joint infection (3.1 versus 1.6%; P < 0.001), periprosthetic fracture (2.4 versus 1.4%; P = 0.003), loosening (1.7 versus 1.0%; P = 0.007), prosthetic dislocation (2.5 versus 1.2%; P < 0.001), and revision surgery (4.1 versus 2.3%; P < 0.001).

Conclusions: Preoperative TRT use was associated with increased risk of medical and prosthetic-related complications following THA.

Background: Periprosthetic joint infection (PJI) remains one of the most devastating complications following total joint arthroplasty. While platelets are recognized for their role in hemostasis, growing evidence suggests they also serve as immune effectors. Experimental data support a link between platelet depletion and infection risk, yet clinical evidence is limited.

Methods: We performed a retrospective cohort study using a large national database to identify patients undergoing primary total knee arthroplasty between 2015 and 2023. Patients were stratified by preoperative platelet count: ≤ 50,000/μL, 50,000 to 99,000/μL, 100,000 to 149,000/μL, and ≥ 150,000/μL. The primary endpoint was PJI within one year, and the secondary endpoint was superficial surgical site infection (SSI). Multivariable logistic regressions and propensity score matching were used to adjust for demographics and comorbidities. Of 182,043 patients included in the study, 8,380 (4.6%) had platelet counts less than 150,000/μL.

Results: In adjusted models, risk of PJI increased stepwise with lower platelet counts: odds ratio (OR) 1.42 (95% confidence interval [CI]: 1.15 to 1.73) for 100,000 to 149,000/μL, OR 3.67 (95% CI: 2.57 to 5.10) for 50,000 to 99,000/μL, and OR 5.12 (95% CI: 1.73 to 12.19) for ≤ 50,000/μL compared with ≥150,000/μL (P-value trend < 0.001). Platelet count was not significantly associated with SSI at any threshold in all models.

Conclusions: Preoperative thrombocytopenia is strongly and progressively associated with increased risk of PJI, but not SSI, after total knee arthroplasty. These results highlight the role of platelets as immune effectors in the periprosthetic space and suggest platelet count and function as underrecognized, potentially modifiable risk factors for arthroplasty infection. Prospective studies are needed to determine whether optimization of platelet levels can reduce PJI risk.

Level of evidence: III.

Background: Although robotic arm-assisted total hip arthroplasty (RA-THA) has been increasing in popularity, the outcomes following its use are still uncertain.

Methods: We performed a propensity-matched prospective cohort study comparing all-cause revision, odds of instability/dislocation, odds of periprosthetic joint infection (PJI), and hospital length of stay (HLOS) between patients receiving an RA-THA versus a conventional total hip arthroplasty (CO-THA). Consecutive patients undergoing a primary elective total hip arthroplasty (THA) via a posterior approach at our institution between January 2019 and February 2024 were included. Those who received a bilateral simultaneous THA were excluded. We successfully matched 268 pairs of hips.

Results: There was no difference in all-cause revision risk between the RA-THA and CO-THA groups (hazard ratio = 1.00, P = 1.000). Furthermore, there was also no significant difference in the odds of instability/dislocation (odds ratio = 1.00, P = 1.000) and the odds of PJI (odds ratio = 0.75, P = 0.704. The HLOS was significantly shorter in the RA-THA cohort by 0.49 days (P = 0.044). The median follow-up duration was 3.46 years (interquartile range: 1.92 to 4.64).

Conclusion: Although there was no difference in short-term revision risk in patients receiving an RA-THA versus a CO-THA, likely, the benefits from improved implant positioning are yet to be realized. This study is underpowered, and results should be interpreted with caution. The shorter HLOS observed in the RA-THA group may help offset the increase in consumable costs incurred. Further studies with long-term follow-up, alongside a cost-effectiveness analysis, are required.

Background: Indications for curved intertrochanteric varus osteotomy (CVO) for osteonecrosis of the femoral head (ONFH) with a beak-shaped healthy area (BHA) remain unclear. This study aimed to evaluate the clinical outcomes and radiographic findings of CVO for ONFH with BHA.

Methods: This comparative study included 77 patients who were Japanese Investigation Committee type B and C1 ONFH. From January 2005 to December 2022, 21 patients (22 hips) who had a BHA underwent CVO (BHA group), whereas 56 patients (62 hips) who did not have a BHA underwent CVO (control group). The average follow-up period was 98.4 and 97.2 months in the BHA and control groups, respectively. Clinical and radiographic evaluations included the Harris Hip Score, complication rates, radiographic parameters, and survival rates. Endpoints were defined as conversion to total hip arthroplasty or radiographic failure.

Results: The preoperative and postoperative Harris Hip Score values were similar between the BHA and control groups. The complication rates were comparable between the groups. The postoperative intact ratio and varus angle showed no significant differences. In the BHA group, three cases of beak fractures occurred within the first year postoperatively. The 8-year survival rate based on conversion to total hip arthroplasty and radiographic failure did not differ significantly between the groups.

Conclusions: The clinical outcomes of CVO for ONFH with BHA were comparable to those of CVO for ONFH without BHA, indicating that CVO may be a viable joint-preserving option even in cases presenting with BHA.