The Statistical Fragility of Tranexamic Acid Use in the Orthopaedic Surgery Literature: A Systematic Review of Randomized Controlled Trials

INTRODUCTION

Randomized controlled trials (RCTs) represent the highest level of evidence in orthopaedic surgery literature, although the robustness of statistical findings in these trials may be unreliable. We used the fragility index (FI), reverse fragility index (rFI), and fragility quotient (FQ) to evaluate the statistical stability of outcomes reported in RCTs that assess the use of tranexamic acid (TXA) across orthopaedic subspecialties.

METHODS

PubMed, EMBASE, and MEDLINE were queried for RCTs (2010-present) reporting dichotomous outcomes with study groups stratified by TXA administration. The FI and rFI were defined as the number of outcome event reversals needed to alter the significance level of significant and nonsignificant outcomes, respectively. FQ was determined by dividing the FI or rFI by sample size. Subgroup analyses were conducted based on orthopaedic subspecialty.

RESULTS

Six hundred five RCTs were screened with 108 studies included for analysis comprising 192 total outcomes. The median FI of the 192 outcomes was 4 (IQR 2 to 5) with an associated FQ of 0.03 (IQR 0.019 to 0.050). 45 outcomes were reported as statistically significant with a median FI of 1 (IQR 1 to 5) and associated FQ of 0.02 (IQR 0.011 to 0.034). 147 outcomes were reported as nonsignificant with a median rFI of 4 (IQR 3 to 5) and associated FQ of 0.04 (IQR 0.023 to 0.051). The adult reconstruction, trauma, and spine subspecialties had a median FI of 4. Sports had a median FI of 3. Shoulder and elbow and foot and ankle had median FIs of 6.

DISCUSSION

Statistical outcomes reported in RCTs on the use of TXA in orthopaedic surgery are fragile. Reversal of a few outcomes is sufficient to alter statistical significance. We recommend reporting FI, rFI, and FQ metrics to aid in interpreting the outcomes reported in comparative trials.

Oral Postoperative Antibiotic Prophylaxis for Outpatient Total Hip and Knee Arthroplasty: Describing Current Practices

BACKGROUND

Despite an increase in outpatient total hip arthroplasty (THA) and total knee arthroplasty (TKA), large-scale data are lacking on current practice for antibiotic prophylaxis prescribing. We aimed to describe current oral antibiotic prophylaxis practices nationally for outpatient THA and TKA.

METHODS

This nationwide retrospective cohort study included primary outpatient THA or TKA procedures in patients aged 18 to 64 years from 2018 to 2021 using a national claims database. Oral antibiotic prescriptions filled perioperatively (defined as 5 days before to 3 days after surgery) were extracted; these were categorized and assumed to represent postoperative prophylaxis. Multivariable logistic regression measured associations between patient and surgery characteristics and perioperative oral antibiotic prophylaxis. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) are reported.

RESULTS

Oral antibiotic prescriptions were filled in 16.5% of 73,015 outpatient THA and TKA (18.4% of 24,857 THAs, 15.5% of 48,158 TKAs) procedures. Prescriptions were most often for cephalosporins (74.3%), with cephalexin (52.8%), and cefadroxil (19.1%) being the most common. Non-cephalosporin antibiotics prescribed were mainly clindamycin (6.8%), sulfamethoxazole-trimethoprim (6.7%), and doxycycline (6.2%). The odds of receiving oral antibiotic prophylaxis were higher for THA compared to TKA (OR 1.13, 95% CI 1.09 to 1.18, P < .001) and in the presence of obesity, diabetes, and autoimmune conditions (OR 1.08 to 1.13, P < .001 to .01). Ambulatory surgery center procedures also had significantly increased odds of prophylaxis compared to hospital-based outpatient surgeries (OR 2.62, 95% CI 2.51 to 2.73, P < .001). Additionally, regional and time-based variations were noted.

CONCLUSIONS

Perioperative oral antibiotic prophylaxis prescriptions were filled in only 16.5% of outpatient THA and TKA cases, with variation in the type of antibiotic prescribed. The receipt of any prophylaxis and specific medications was associated with demographic, clinical, and procedure-related characteristics. Follow-up research will evaluate associations with infection risk reduction.

Characteristics and Quality of Online Searches for Direct Anterior Versus Posterior Approach for Total Hip Arthroplasty

BACKGROUND

Online resources are important for patient self-education and reflect public interest. We described commonly asked questions regarding the direct anterior versus posterior approach (DAA, PA) to total hip arthroplasty (THA) and the quality of associated websites.

METHODS

We extracted the top 200 questions and websites in Google's "People Also Ask" section for 8 queries on January 8, 2023, and grouped websites and questions into DAA, PA, or comparison. Questions were categorized using Rothwell's classification (fact, policy, value) and THA-relevant subtopics. Websites were evaluated by information source, Journal of the American Medical Association Benchmark Criteria (credibility), DISCERN survey (information quality), and readability.

RESULTS

We included 429 question/website combinations (questions: 52.2% DAA, 21.2% PA, 26.6% comparison; websites: 39.0% DAA, 11.0% PA, 9.6% comparison). Per Rothwell's classification, 56.2% of questions were fact, 31.7% value, 10.0% policy, and 2.1% unrelated. The THA-specific question subtopics differed between DAA and PA (P < .001), specifically for recovery timeline (DAA 20.5%, PA 37.4%), indications/management (DAA 13.4%, PA 1.1%), and technical details (DAA 13.8%, PA 5.5%). Information sources differed between DAA (61.7% medical practice/surgeon) and PA websites (44.7% government; P < .001). The median Journal of the American Medical Association Benchmark score was 1 (limited credibility, interquartile range 1 to 2), with the lowest scores for DAA websites (P < .001). The median DISCERN score was 55 ("good" quality, interquartile range 43 to 65), with the highest scores for comparison websites (P < .001). Median Flesch-Kincaid Grade Level scores were 12th grade level for both DAA and PA (P = .94).

CONCLUSIONS

Patients' informational interests can guide counseling. Internet searches that explicitly compare THA approaches yielded websites that provide higher-quality information. Providers may also advise patients that physician websites and websites only describing the DAA may have less balanced perspectives, and limited information regarding surgical approaches is available from social media resources.

Prior COVID-19 and Venous Thromboembolism Risk in Total Joint Arthroplasty in Patients Over 65 Years of Age

BACKGROUND

The COVID-19 pandemic has been associated with increased risks of venous thromboembolism (VTE), including deep vein thrombosis (DVT) and pulmonary embolism (PE). However, there is limited literature investigating prothrombotic states and complications after total hip arthroplasty (THA) and total knee arthroplasty (TKA). We investigated (1) trends in VTE, PE, and DVT rates post-THA and TKA from 2016 to 2019 compared to 2020 to 2021 and (2) associations between prior COVID-19 diagnosis and VTE, PE, and DVT.

METHODS

A national dataset was queried for elective THA and TKA cases from 2016 to 2021. We first assessed trends in 90-day VTE prevalence between 2016 to 2019 and 2020 to 2021. Second, we investigated associations between previous COVID-19 and 90-day VTE with regression models.

RESULTS

From 2016 to 2021, a total of 2,422,051 cases had an annual decreasing VTE prevalence from 2.2 to 1.9% (THA) and 2.5 to 2.2% (TKA). This was evident for both PE and DVT (all trend tests P < .001). After adjusting for covariates (including vaccination status), prior COVID-19 was associated with significantly increased odds of developing VTE in TKA patients (odds ratio 1.2, 95% confidence interval 1.1 to 1.4, P = .007), but not DVT or PE (P > .05). There were no significant associations between prior COVID-19 and VTE, DVT, or PE after THA (P > .05).

CONCLUSIONS

Our study suggests that a previous diagnosis of COVID-19 is associated with increased odds of VTE, but not DVT or PE, in TKA patients. Ongoing data monitoring is needed given our effect estimates, emerging COVID-19 variants, and evolving vaccination rates.

Statistical Outcomes Guiding Periprosthetic Joint Infection Prevention and Revision Are Fragile: A Systematic Review of Randomized Controlled Trials

BACKGROUND

Dichotomous outcomes are frequently reported in orthopaedic research and have substantial clinical implications. This study utilizes the fragility index (FI) and fragility quotient (FQ) metrics to determine the statistical stability of outcomes reported in total joint arthroplasty randomized controlled trials (RCTs) relating to periprosthetic joint infection (PJI).

METHODS

The RCTs that reported dichotomous data related to PJI published between January 1, 2010, and December 31, 2022, were evaluated. The FI and reverse FI (RFI) were defined as the number of outcome event reversals required to reverse the significance of significant and nonsignificant outcomes, respectively. The FQ was determined by dividing the FI or RFI by the respective sample size. There were 108 RCTs screened, and 17 studies included for analysis.

RESULTS

A total of 58 outcome events were identified, with a median FI of 4 (interquartile range [IQR] 2 to 5) and associated FQ of 0.0417 (IQR 0.0145 to 0.0602). The 13 statistically significant outcomes had a median FI of 1 (IQR 1 to 2) and FQ of 0.00935 (IQR 0.00629 to 0.01410). The 45 nonsignificant outcomes had a median RFI of 4 (IQR 3 to 5) and FQ of 0.05 (IQR 0.0361 to 0.0723). The number of patients lost to follow-up was greater than or equal to the FI in 46.6% of outcomes.

CONCLUSIONS

Statistical outcomes in RCTs analyzing PJI are fragile and may lack statistical integrity. We recommend a comprehensive fragility analysis, with the reporting of FI and FQ metrics, to aid in the interpretation of outcomes in the total joint arthroplasty literature.

Synthesis of 'joint class' curricula at high volume joint replacement centres and a preliminary model for development and evaluation

RATIONALE

Preoperative patient education through 'joint class' has potential to improve quality of care for total joint replacement (TJR). However, no formal guidance exists regarding curriculum content, potentially resulting in inter-institutional variation.

OBJECTIVE

We aimed to (a) synthesize curriculum components of 'joint classes' across high-volume institutions and (b) develop a preliminary theory of change model for development and evaluation guided by the existing curricula and related literature.

METHODS

We reviewed 'joint class' curricula from the websites of the 10 highest-volume TJR centres (by average annual 2017-2019 volume) that publicly disclosed this information. Two reviewers qualitatively compared available content and noted common categories, which were synthesized into key domains across institutions. We then reviewed the PubMed database for literature on pre-TJR patient education and education needs in the past 10 years. Drawing on our curriculum synthesis and related literature, we proposed a theory of change model: hypothesized mechanisms through which 'joint class' confers benefits to patients and health systems.

RESULTS

We identified 30 categories in our review of existing class content, which we synthesized into seven key domains: (I) Practical Elements, (II) Logistics, (III) Medical Information, (IV) Modifiable Risk Factors, (V) Expected Outcomes, (VI) Patient Role in Recovery and (VII) Enhanced Education. Variation across institutions was noted. Our preliminary model based on the curriculum synthesis and related literature on the impact of 'joint class' includes three levels: (1) Practical Elements ('joint class' accessibility and information quality), (2) Class Goals (increased health literacy, increased adherence, risk mitigation, realistic expectations, and reduced anxiety) and (3) Target Outcomes (improved clinical outcomes, positive patient experience and increased patient satisfaction).

CONCLUSION

Our synthesis identified core common topics included in pre-TJR education but also highlighted variation across institutions, supporting opportunities for standardization. Clinicians and researchers can use our preliminary model to systematically develop and evaluate 'joint classes,' with the goal of establishing a standard of care for TJR preoperative education.

Adverse Local Tissue Reaction Secondary to Corrosion at Multiple Junctions in a Modular, Segmental, Distal Femoral Replacement

While adverse local tissue reactions are well described in the total hip arthroplasty literature, there have only been case reports and case series in the total knee arthroplasty literature. There have been no cases described in the setting of a distal femoral replacement. In this case, we describe a 69-year-old female with a complex history of left knee revision arthroplasty with a distal femoral and proximal tibial replacement who presented with left knee pain and was found to have extensive adverse local tissue reaction with corrosion at the femoral stem-extension piece junction and the extension piece-distal femoral component junction. The femoral taper was then manually cleaned and modular components replaced. Corrosion at the stem-distal femoral component junction can result in adverse local tissue reaction in patients with distal femoral replacements. It is important to consider this diagnosis when evaluating patients with knee pain following distal femoral replacement.

Did the COVID-19 Pandemic Coincide With an Increase in Osteonecrosis as Indication for Total Hip Arthroplasty in Older Patients?

BACKGROUND

Osteonecrosis of the femoral head is a common indication for total hip arthroplasty (THA). It is unclear to what extent the COVID-19 pandemic has impacted its incidence. Theoretically, the combination of microvascular thromboses and corticosteroid use in patients who have COVID-19 may increase the risk of osteonecrosis. We aimed to (1) assess recent osteonecrosis trends and (2) investigate if a history of COVID-19 diagnosis is associated with osteonecrosis.

METHODS

This retrospective cohort study utilized a large national database between 2016 and 2021. Osteonecrosis incidence in 2016 to 2019 was compared to 2020 to 2021. Secondly, utilizing a cohort from April 2020 through December 2021, we investigated whether a prior COVID-19 diagnosis was associated with osteonecrosis. For both comparisons, Chi-square tests were applied.

RESULTS

Among 1,127,796 THAs performed between 2016 and 2021, we found an osteonecrosis incidence of 1.6% (n = 5,812) in 2020 to 2021 compared to 1.4% (n = 10,974) in 2016 to 2019; P < .0001. Furthermore, using April 2020 to December 2021 data from 248,183 THAs, we found that osteonecrosis was more common among those who had a history of COVID-19 (3.9%; 130 of 3,313) compared to patients who had no COVID-19 history (3.0%; 7,266 of 244,870); P = .001).

CONCLUSION

Osteonecrosis incidence was higher in 2020 to 2021 compared to previous years and a previous COVID-19 diagnosis was associated with a greater likelihood of osteonecrosis. These findings suggest a role of the COVID-19 pandemic on an increased osteonecrosis incidence. Continued monitoring is necessary to fully understand the impact of the COVID-19 pandemic on THA care and outcomes.

Risk of Infection After Total Knee or Hip Arthroplasty After Receipt of Multiple Corticosteroid or Hyaluronic Acid Injections

BACKGROUND

Few studies have assessed the relationship between the quantity of preoperative corticosteroid injections (CSIs) or hyaluronic acid injections (HAIs) and postoperative infection risk after total knee or hip arthroplasty (TKA, THA). We aimed to (1) determine whether the number of injections administered before TKA/THA procedures is associated with postoperative infections and (2) establish whether infection risk varies by injection type.

METHODS

This retrospective cohort study included 230,487 THAs and 371,511 TKAs from the 2017 to 2018 Medicare Limited Data Set. The quantity of CSI or HAI, defined as receiving either CSI or HAI ≤2 years before TKA/THA, was identified and categorized as 0, 1, 2, or >2. The primary outcome was 90-day postoperative infection. Multivariable regression models measured the association between the number of injections and 90-day postoperative infection. Odds ratios and 95% confidence intervals were reported.

RESULTS

The percentage of THA patients receiving 1, 2, and >2 preoperative CSIs was 6.1%, 1.6%, and 0.8%, respectively. Receiving >2 CSIs within 2 years before THA was associated with higher odds of 90-day postoperative infection (odds ratios = 1.74, 95% CI = 1.11 to 2.74, P = 0.02). The percentage of TKA patients receiving 1, 2, and >2 CSIs was 3.0%, 1.2%, and 1.1%, respectively. For HAIs in TKA patients, percentage receiving injections was 98.3%, 0.6%, 0.2%, and 0.9%, respectively. Quantity of CSIs or HAIs administered was not associated with postoperative infection among TKA patients.

CONCLUSION

Patients receiving >2 injections before THA had higher odds of 90-day postoperative infection. This finding was not observed in TKA patients. These results suggest that the use of >2 injections within 2 years of THA should be avoided.

Sleep Disturbance Trends in the Short-Term Postoperative Period for Patients Undergoing Total Joint Arthroplasty

BACKGROUND

Patients undergoing total joint arthroplasty (TJA) often experience preoperative/postoperative sleep disturbances. Although sleep quality generally improves > 6 months after surgery, patterns of sleep in the short-term postoperative period are poorly understood. This study sought to (1) characterize sleep disturbance patterns over the 3-month postoperative period and (2) investigate clinical and sociodemographic factors associated with 3-month changes in sleep.

METHODS

This retrospective analysis of prospectively collected data included 104 primary elective TJA patients. Patients were administered the PROMIS Sleep Disturbance questionnaire preoperatively and at 2 weeks, 6 weeks, and 3 months postoperatively. Median sleep scores were compared between time points using Wilcoxon signed-rank tests, stratified by preoperative sleep impairment. A multivariable logistic regression model identified factors associated with 3-month clinically improved sleep.

RESULTS

The percentage of patients reporting sleep within normal limits increased over time: 54.8% preoperatively and 58.0%, 62.5%, and 71.8% at 2 weeks, 6 weeks, and 3 months post-TJA, respectively. Patients with normal preoperative sleep experienced a transient 4.7-point worsening of sleep at 2 weeks ( P = 0.003). For patients with moderate/severe preoperative sleep impairment, sleep significantly improved by 5.4 points at 2 weeks ( P = 0.002), with improvement sustained at 3 months. In multivariable analysis, patients undergoing total hip arthroplasty (versus knee; OR: 3.47, 95% CI: 1.06 to 11.32, P = 0.039) and those with worse preoperative sleep scores (OR: 1.13, 95% CI: 1.04 to 1.23, P = 0.003) were more likely to achieve clinically improved sleep from preoperatively to 3 months postoperatively.

DISCUSSION

Patients experience differing patterns in postoperative sleep changes based on preoperative sleep disturbance. Hip arthroplasty patients are also more likely to experience clinically improved sleep by 3 months compared with knee arthroplasty patients. These results may be used to counsel patients on postoperative expectations and identify patients at greater risk of impaired postoperative sleep.

STUDY DESIGN

Retrospective analysis of prospectively collected data.

The Fragility of Tourniquet Use in Total Knee Arthroplasty: A Systematic Review of Randomized Controlled Trials

BACKGROUND

Physicians utilize P-values to interpret clinical trial data and guide patient-care decisions. Fragility analysis assesses the stability of statistical findings in relation to outcome event reversals. This study assessed the statistical fragility of recent randomized controlled trials (RCTs) investigating tourniquet use in total knee arthroplasty (TKA).

METHODS

We queried PubMed, EMBASE, and MEDLINE for RCTs comparing outcomes in TKA based on tourniquet use. Fragility index (FI) and reverse fragility index (reverse FI) were calculated - for significant and nonsignificant outcomes, respectively - as the number of outcome reversals required to change statistical significance. The fragility quotient (FQ) was calculated by dividing the FI or reverse FI by the sample size. Median overall FI and FQ were calculated for all included outcomes, and sub-analyses were performed by reported significance. The literature search yielded 23 studies reporting 91 total dichotomous outcomes.

RESULTS

Overall median FI was 4 with an interquartile range (IQR) of 3 to 6. Overall median FQ was 0.0476 (IQR 0.0291 to 0.0867). A total of 11 outcomes were statistically significant with a median FI and FQ of 2 (IQR 1.5 to 5) and 0.0200 (IQR 0.0148 to 0.0484), respectively. There were 80 outcomes that were nonsignificant with a median reverse FI of 4 (IQR 3 to 6). Loss to follow-up was greater than the median FI in 17.6% of outcomes.

CONCLUSION

Altering a small number of outcomes is often sufficient to reverse findings in RCTs evaluating tourniquet use in TKA. We recommend including fragility analyses to increase reliability in the interpretation of study conclusions.

Relationships Between Preoperative Mental Health and Improvements in Patient-Reported Outcomes After Total Hip and Knee Arthroplasty

BACKGROUND

Poor preoperative mental health has been associated with worse outcomes after total hip (THA) and total knee arthroplasty (TKA). To fully understand these relationships, we assessed post-THA and post-TKA improvements in patient-reported mental and joint health by preoperative mental health groups.

METHODS

Elective cases (367 THA, 462 TKA) were subgrouped by low (<25th percentile), middle (25th-74th), and high (≥75th) preoperative mental health, using Veterans RAND 12-Item Health Survey Mental Component Summary (MCS) scores. In each subgroup, we assessed the relationship between preoperative MCS and 1-year postoperative change in mental and joint health. Pairwise comparisons and multivariable regression models were applied for THA and TKA separately.

RESULTS

Median postoperative mental health change was +14.0 points for the low-MCS THA group, +11.1 low-TKA, +2.0 middle-THA and TKA, -4.0 high-THA, and -4.9 high-TKA (between-group differences P < .001). All MCS groups had improved median joint health scores, without significant between-group differences. Preoperative mental health was negatively associated with mental health improvements in all groups (B = -0.94 - -0.68, P < .001-P = .01) but with improvements in joint health only in the low-THA group (B = -0.74, P = .02). Improvements in mental and joint health were positively associated for low and middle (B = 0.61-0.87, P < .001), but not for high-MCS groups, with this relationship differing for the low versus high group.

CONCLUSION

Patients who have low preoperative mental health experienced greater postoperative mental health improvement and similar joint health improvement compared to patients who have high preoperative mental health. Findings can guide subgroup-targeted surgical decision-making and preoperative counseling.

Treatment patterns and failure rates associated with prosthetic joint infection in unicompartmental knee arthroplasty: A systematic review

Background

Prosthetic joint infection (PJI) following unicompartmental knee arthroplasty (UKA) is a rare but challenging complication. A paucity of literature exists regarding the management of PJI in UKA. This systematic review aims to assess current treatment patterns in UKA PJI and analyze the failure rates associated with treatment.

Methods

PubMed, Scopus, and EMBASE were systematically searched for studies that presented cases of PJI following UKA. Data regarding study design, country of publication, index procedure type, diagnosis of PJI, number and incidence of PJI, timing of PJI (acute versus chronic), treatment, and outcomes were recorded. Failure rates in acute and chronic PJI as well as total failure rates were analyzed.

Results

Sixteen articles were identified that met inclusion criteria. These included 97 PJI cases (37 acute, 58 chronic, 2 unknown timing); incidence across all studies of 0.80%. The most common treatment for all PJI cases was debridement, antibiotics, and implant retention (DAIR) (40.2%), followed by two-stage conversion to total knee arthroplasty (TKA) (33.0%), one-stage conversion to TKA (23.7%), and one-stage exchange UKA (3.1%). There were no significant differences in failure rates across procedures for acute, chronic or overall PJI management (p > 0.05 for all).

Conclusion

This systematic review found relatively few studies reporting on PJI after UKA compared to the available TKA evidence. Further research is warranted to better elucidate the most appropriate treatment of PJI after UKA in both the acute and chronic setting along with risk factors for failure.

Comparison of total joint arthroplasty care patterns prior to the Covid-19 pandemic and after resumption of elective surgery during the Covid-19 Outbreak: A retrospective, large urban academic center study

BACKGROUND

After the suspension of elective surgeries was lifted in June 2020 in New York State, challenges remained regarding coordination of total joint arthroplasty (TJA) cases. Using the experience from a high-volume health system in New York City, we aimed to describe patterns of care after resumption of elective TJA.

METHODS

We retrospectively assessed 7,699 TJAs performed before and during the COVID-19 pandemic. Perioperative characteristics and clinical outcomes were compared between TJAs based on time period of performance: 1) pre-pandemic (PP, June 8th-December 8th, 2019), 2) initial period post-resumption of elective surgeries (IR, June 8th-September 8th, 2020), and 3) later period post-resumption (LR, September 9th-December 8th, 2020).

RESULTS

LOS > 2 days (83%, 67%, 70% for PP, IR, LR periods respectively) and discharge rates to post-acute care (PAC) facilities were lower during the pandemic periods (OR_{IR vs. PP}: 0.48, 95% CI: 0.40-0.59, p < 0.001; OR_{LR vs. PP}: 0.63, 95% CI: 0.53-0.75, p < 0.001). Compared to the pre-pandemic period, the risk for 30-day readmission was lower during the IR period (OR: 0.62, 95% CI: 0.40-0.98, p = 0.041) and similar during the LR period (OR: 0.96, 95% CI: 0.65-1.41, p = 0.832).

CONCLUSIONS

Despite decreased LOS and discharge to PAC for TJAs performed during the pandemic, 30-day readmissions did not increase. Given the increased costs and lack of superior functional outcomes associated with discharge to PAC, these findings suggest that discharge to PAC facilities need not return to pre-pandemic levels.

Racial Differences in Manipulation Under Anesthesia Rates Following Total Knee Arthroplasty

BACKGROUND

Despite the extensive literature on racial disparities in care and outcomes after total knee arthroplasty (TKA), data on manipulation under anesthesia (MUA) is lacking. We aimed to determine (1) the relationship between race and rate of (and time to) MUA after TKA, and (2) annual trends in racial differences in MUA from 2013 to 2018.

METHODS

This retrospective cohort study (using 2013-2018 Medicare Limited Data Set claims data) included 836,054 primary TKA patients. The primary outcome was MUA <1 year after TKA; time from TKA to MUA in days was also recorded. A mixed-effects multivariable model measured the association between race (White, Black, Other) and odds of MUA. Odds ratios (OR) and 95% confidence intervals (CI) were reported. A Cochran Armitage Trend test was conducted to assess MUA trends over time, stratified by race.

RESULTS

MUA after TKA occurred in 1.7%, 3.2% and 2.1% of White, Black, and Other race categories, respectively (SMD = 0.07). After adjustment for covariates, (Black vs White) patients had increased odds of requiring an MUA after TKA: odds ratio (OR) 1.97, 95% confidence intervals (CI) 1.86-2.10, P < .0001. Moreover, White (compared to Black) patients had significantly shorter time to MUA after TKA: 60 days (interquartile range [IQR] 46-88) versus 64 days (interquartile range [IQR] 47-96); P < .0001. These disparities persisted from 2013 through 2018.

CONCLUSION

Continued racial differences exist for rates and timing of MUA following TKA signifying the continued need for efforts aimed toward understanding and eliminating inequalities that exist in total joint arthroplasty (TJA) care.

National Decline in Knee Fusions Performed for Salvage of Chronic Periprosthetic Total Knee Infections

The primary purpose of this study was to study and compare rates of two salvage operations for patients with chronically infected total knee arthroplasties: (1) knee arthrodesis and (2) above knee amputation (AKA). An analysis was performed comparing the inpatient hospital characteristics and complications between the two procedures. Secondarily, we presented rates of all surgically treated periprosthetic total knee infections over a 6-year period. Using the Nationwide Inpatient Sample, we identified all patients with a periprosthetic infection (International Classification of Diseases, Ninth Revision [ICD-9] 996.66) from 2009 to 2014. Subsequently, we identified surgically treated total knee infections through the following ICD-9 codes: 00.80 (all component revision), 00.84 (liner exchange), 80.06 (removal of prosthesis), 84.17 (AKA), and 81.22 (knee fusion). From 2009 to 2014, the annual incidence of surgically treated total knee periprosthetic infections increased by 34.9% nationally, while the annual incidence of primary total knees increased by only 13.9%. Salvage operations (AKA and knee fusion) represented 5.8% of all surgically treated infections. The rate of knee fusions decreased from 1.9% of surgically treated infections in 2009 to 1.4% in 2014 (p < 0.05), while the rate of AKA stayed steady at 4.5% of cases over the 6-year period. Length of stay was significantly shorter in the knee fusion group (7.9 vs. 10.8 days, p < 0.05), but total hospital costs were higher (33,016 vs. 24,933, p < 0.05). In the multivariable adjusted model, patients undergoing knee fusion had significantly decreased odds of being discharged to skilled nursing facility (odds ratio: 0.42, 95% confidence interval: 0.31-0.58). The annual incidence of surgically treated periprosthetic total knee infections is increasing. The rate of knee arthrodesis for chronic periprosthetic total knee infections is decreasing. Reasons for this downward trend in knee fusions should be evaluated carefully as knee fusions have shown to have the potential advantage of improved mobility and decreased patient morbidity for chronic PJI. The level of evidence is III.

No Difference Between Hemiarthroplasty and Total Hip Arthroplasty in the Treatment of Pathologic Femoral Neck Fractures

BACKGROUND

Hemiarthroplasty (HA) and total hip arthroplasty (THA) have been widely discussed as treatment options for displaced osteoporotic femoral neck fractures. Pathologic femoral neck fractures from primary or metastatic tumors are comparatively rare and poorly investigated. The purpose of this study was to compare outcomes, complications, and perioperative survival for HA and THA in the treatment of pathologic femoral neck fractures of neoplastic etiology.

METHODS

A multicenter retrospective cohort study identified patients with pathologic femoral neck fractures treated with HA or THA from 2005 to 2018. Demographics, American Society of Anesthesiologists classification, Charlson comorbidity index, Dorr classification, histopathologic diagnosis, and surgical data were compared. The primary outcome was reoperation. Secondary outcomes included 90-day mortality, estimated blood loss, length of stay, periprosthetic fracture, periprosthetic joint infection, and Eastern Cooperative Oncology Group performance status.

RESULTS

There were 116 patients with HA and 48 patients with THA, with no differences between groups with regard to American Society of Anesthesiologists classification, Charlson comorbidity index, or Dorr classification. There were no differences between HA and THA in the primary outcome of reoperation (5.2% vs 4.2%, P = 1.00) or secondary outcomes of perioperative 90-day overall mortality (30.2% vs 25.0%, P = .51), estimated blood loss, transfusion rates, length of stay, discharge location, periprosthetic joint infection, periprosthetic fracture, or preoperative or postoperative Eastern Cooperative Oncology Group performance status.

CONCLUSIONS

Both HA and THA are viable options for the treatment of patients with pathologic femoral neck fractures and demonstrated no differences in reoperations, complications, perioperative 90-day mortality, or functional outcome scores.

LEVEL OF EVIDENCE

Level III.

Morbidity and mortality of surgically treated pathologic humerus fractures compared to native humerus fractures

BACKGROUND

Despite an increasing prevalence of patients sustaining pathologic fractures of neoplastic origin, few studies have investigated 30-day postoperative complication profiles after surgical treatment of pathologic humerus fractures. The purposes of this study were to use a large nationally representative database to determine short-term complication profiles after surgical treatment of pathologic humerus fractures and assess how these complications compared with more commonly studied native humerus fractures.

METHODS

Using the National Surgical Quality Improvement Program database, we identified 30,866 patients who underwent surgical treatment for either pathologic (n = 449) or native humerus fractures (n = 30,417) from 2007 to 2017. Thirty-day postoperative complication profiles were ascertained and compared between the 2 groups using χ² analyses. Three logistic regression models were then performed to determine which complications were primarily attributable to the pathologic fracture itself vs. the increased comorbidity burden faced by these patients.

RESULTS

Patients with pathologic humerus fractures experienced significantly higher rates of death (6.0% vs. 0.3%, P < .001), serious adverse events (12.2% vs. 3.7%, P < .001), minor complications (15.8% vs. 4.8%, P < .001), extended postoperative lengths of stay (42.3% vs. 21.3%, P < .001), discharge to facilities (22.3% vs. 13.5%, P < .001), and readmissions (14.8% vs. 3.4%, P < .001) compared with patients with native humerus fractures. With respect to specific complications, patients with pathologic fractures were at significantly higher risk of pulmonary complications (1.3% vs. 0.3%, P < .001), renal complications (0.7% vs. 0.2%, P = .007), thromboembolic complications (1.6% vs. 0.6%, P = .01), and transfusions (15.1% vs. 4.1%, P < .001).

CONCLUSION

After surgical treatment, patients with pathologic humerus fractures had significantly higher complication rates compared with native humerus fractures, suggesting that guidelines and treatment algorithms for native humerus fractures may not be generalizable for those of pathologic origin. These findings have significant implications for preoperative patient counseling and may be used to negotiate higher reimbursement rates for these patients given a significantly higher morbidity and mortality than was previously described in literature. Postoperatively, orthopedic surgeons should closely monitor patients with pathologic humerus fractures for deep vein thrombosis, renal complications, and pulmonary complications, use blood-sparing techniques, and employ a multidisciplinary approach to help manage and prevent a more heterogeneous profile of postsurgical complications.

Tranexamic acid in patients with current or former cancer undergoing hip and knee arthroplasty

BACKGROUND AND OBJECTIVES

While tranexamic acid (TXA) is an excellent mechanism to reduce blood loss in arthroplasty, its safety in cancer patients-who could potentially benefit the most from blood conservation-is unknown.

METHODS

A multicenter, retrospective review of current or former cancer patients undergoing hip/knee arthroplasty from 2014 to 2019 was performed. The use of intravenous TXA, indication (oncologic/degenerative), cancer state, cancer type, surgical factors, demographics, and comorbidities were collected. The association between TXA use and 90-day/1-year complications was analyzed with multivariable logistic regressions.

RESULTS

We identified 282 patients with current (87.9%) or former (12.1%) malignancies undergoing arthroplasty (73.0% oncologic/27.0% degenerative). About 74 (26.2%) patients received TXA (52.7% had oncologic indications, 74.3% had active cancer). In adjusted analysis, TXA was not associated with increased risk of venous thromboembolism within 90-days (odds ratio [OR] 0.59; 95% confidence interval [CI] 0.16-2.16, p = 0.43) or 1-year (OR 0.47; 95%CI 0.15-1.44, p = 0.19), with a trend towards lower risk. Similar results were seen for mortality and wound complications, and when stratifying by indication.

CONCLUSION

TXA was not associated with increased complications in current or former cancer patients undergoing arthroplasty. Future randomized studies of TXA in arthroplasty should include cancer patients; in the interim, clinicians should weigh the theoretical risks of TXA with the known benefits of reduced blood loss in oncology patients.

Early Outcome Comparison of the Posterior Approach and the Superior Approach for Primary Total Hip Arthroplasty

Background

The superior approach for total hip arthroplasty (THA) is a minimally invasive, tissue-sparing technique that may have clinical and economic benefits. The purpose of this study was to compare early outcomes between the posterior approach and the superior approach in primary THA. Our hypothesis was that the superior approach would have a noninferior length of stay (LOS), discharge destination, and blood loss compared with the posterior approach.

Methods

All primary THAs performed by a single surgeon at one institution were retrospectively reviewed over a 2-year period (2015-2017). There were 676 patients, 40.4% of whom underwent a posterior approach and 59.6% underwent a superior approach. LOS, discharge destination, blood loss, and operating room time were analyzed. Gender, body mass index, and American Society of Anesthesiologists status were recorded and controlled.

Results

The posterior approach was independently associated with an almost threefold higher risk of prolonged LOS (>2 days, P < .001) (odds ratio: 2.90, 95% confidence interval: 1.87-4.49; P < .001). The mean LOS for the superior approach was 1.71 days vs 2.17 days for the posterior group (P < .001). Fewer patients in the superior approach cohort were discharged to a rehabilitation facility (8.9% vs 17.9%, P < .001). The mean operative time was shorter in the superior group (91.8 vs 95.8, P = .001). There was no statistically significant difference in acute postoperative blood loss. There were no dislocations or reoperations in either group.

Conclusions

The superior approach to THA was associated with a significantly shorter length of hospital stay and lower rate of discharge to rehab than the posterior approach. This approach can be used as a safe, minimally invasive, and tissue-sparing variation of a standard posterior approach for THA and has promising early outcomes.

Pathologic Versus Native Hip Fractures: Comparing 30-day Mortality and Short-term Complication Profiles

BACKGROUND

A large body of research on native hip fractures has resulted in several evidence-based guidelines aimed at improving postsurgical care for these patients. In contrast, there is a paucity of data on pathologic hip fractures, and whether native hip fracture protocols are generalizable to this population is unknown. The purpose of this study was to compare mortality rates and complication profiles between patients with pathologic and native hip fractures.

METHODS

Using the American College of Surgeons-National Surgical Quality Improvement Program (NSQIP) database, we identified patients who underwent surgical treatment for pathologic and native hip fractures from 2007 to 2017 and 2601 matched pairs were identified using propensity scoring. Baseline covariates were controlled for, and rates of 30-day postoperative complications and mortality were compared using McNemar's test.

RESULTS

Pathologic hip fracture patients experienced significantly higher rates of death (6.3% vs 4.3%, P < .001), serious adverse events (17.3% vs 13.5%, P < .001), minor complications (34.3% vs 29.1%, P < .001), extended postoperative lengths of stay (30.2% vs 25.9%, P < .001), readmissions (11.9% vs 8.4%, P < .001), thromboembolic complications (3.0% vs 1.6%, P < .001), and perioperative transfusions (31.5% vs 26.4%, P < .001) compared to native hip fracture patients.

CONCLUSION

Pathologic hip fractures result in significantly higher complication rates than native hip fractures after surgical treatment, suggesting that guidelines for native hip fractures may not be generalizable for pathologic hip fractures. Orthopedic surgeons should closely monitor these patients for deep vein thrombosis, utilize blood sparing techniques, and employ a multidisciplinary approach to help manage and prevent a more heterogenous profile of postsurgical complications.

Short-Term Morbidity and Mortality After Hemiarthroplasty and Total Hip Arthroplasty for Pathologic Proximal Femur Fractures

BACKGROUND

As oncology patients have increasing life expectancies, total hip arthroplasty (THA) may become an important treatment option for pathologic proximal femur fractures (PPFFs). Although THA and hemiarthroplasty (HA) have been compared for native hip fracture treatment, no data on short-term morbidity and mortality are available in the pathologic setting. The purpose of this study is to compare short-term morbidity and mortality of HA vs THA for PPFFs.

METHODS

The National Surgical Quality Improvement Program database was queried from 2007 to 2017 for patients with PPFFs treated with HA or THA. Propensity-adjusted logistic regressions were implemented to compare 30-day morbidity and mortality between procedures. Backwards stepwise regression was then used to determine independent predictors of treatment with HA compared to THA.

RESULTS

In adjusted analysis, THA was associated with longer operative times (120.3 ± 5.6 vs 98.7 ± 4.9 minutes, P < .001); however, there were no differences between THA and HA with regard to 30-day rates of major complications (P = .3), minor complications (P = .77), reoperations (P = .99), readmissions (P = .35), or deaths (P = .63). Older age (P < .001), dependent functional status (P = .02), and the presence of disseminated cancer (P = .049) were predictive of undergoing HA compared to THA.

CONCLUSION

As patients with metastatic cancer continue to live longer with their disease, the durability of surgical reconstruction to treat PPFFs is becoming increasingly important. This study demonstrated no significant differences in 30-day complications between PPFF patients treated with THA or HA after controlling for underlying confounders. These results suggest that THA can be utilized to treat certain patients with PPFFs, and future work is warranted to examine long-term functional outcomes.

Osteosarcoma of the proximal tibia: limb-sparing resection and reconstruction with a modular segmental proximal tibia tumor prosthesis

A limb-sparing resection was performed for osteosarcoma of the proximal tibia in a young patient. A special modular segmental proximal tibial endoprosthesis that includes a hinged total knee component was used for reconstruction. A medial gastrocnemius rotational flap was utilized to reconstruct the extensor mechanism of the knee. The muscle flap aids in covering the prosthesis and helps to protect against infection. Limb-sparing resection for tumors arising from the proximal tibia, and reconstruction with a modular segmental proximal tibia tumor prosthesis and gastrocnemius muscle flap, is a safe and reliable method for treating tumors involving this area.

Limb-sparing resection of the scapula and reconstruction with a constrained total scapula prosthesis: a case of multicentric epithelioid hemangioendothelioma involving the scapula and surrounding soft tissues

INTRODUCTION

The scapula is a relatively uncommon site for primary bone sarcomas. Tumors arising from the scapula are often initially contained by the rotator cuff muscles that protect pertinent adjacent muscles as well as the brachial plexus and axillary blood vessels. Limb-sparing resection of a scapula sarcoma is technically complex and requires meticulous dissection and mobilization of the brachial plexus and axillary blood vessels. Several muscles must be capable of being preserved in order to reconstruct the scapula and shoulder girdle with a special customized total scapula replacement. The goal of reconstruction is to restore a stable shoulder girdle to preserve elbow and hand function.

METHODS AND RESULTS

In the procedure demonstrated in this video, limb-sparing scapula resection and reconstruction was performed for a patient with a multicentric epithelioid hemangioendothelioma. The steps of the procedure are detailed along with accommodations made for the multicentric nature of the tumor. To allow for optimal postoperative function and maximum soft tissue coverage, a small constrained scapular prosthesis was utilized. The glenohumeral ligaments were reconstructed with a Gore-Tex aortic graft. Multiple muscle rotation flaps were performed to cover and protect the prosthesis as well as restore shoulder girdle stability.

CONCLUSION

Limb-sparing surgery for scapula sarcomas and anatomic reconstruction with a constrained total scapula prosthesis is a reliable and safe technique for resecting selected sarcomas and reconstructing the shoulder girdle. A stable shoulder girdle can be restored for optimal hand and elbow function. A total scapula prosthetic reconstruction is the authors' procedure of choice when the deltoid, trapezius, rhomboid, latissimus, and serratus anterior muscles are capable of being preserved. The functional outcome is superior to a forequarter amputation and a flail (nonreconstructed) shoulder in which the extremity is left hanging by soft tissues (nonanatomic method).

Can the oxytocin challenge test serve as the primary method for managing high-risk pregnancies?

The purpose of this investigation was to determine whether the oxytocin challenge test (OCT) could serve as the primary method for managing pregnancies characterized by possible placental insufficiency. One hundred and five patients underwent 225 oxytocin challenge tests; no perinatal deaths occurred. Eight tests were positive, 21 suspicious, and 196 negative. Because of data obtained in a preliminary study, all 8 fetuses with positive tests were delivered by cesarean section. Four of the 8 had repetitive suspicious tests prior to a positive test, suggesting that utero-placental function may deteriorate gradually. Urinary excretion of estriol did not decrease significantly in any patient, suggesting that the OCT is a more sensitive indicator of placental function than excretion of estriol. Except for patients with preeclampsia who were induced for maternal indications, all pregnancies with a negative OCT were allowed to terminate spontaneously. Five of the 97 fetuses with negative tests developed late-onset deceleration patterns during labor. This indicates that a negative OCT will not necessarily predict fetal tolerance to labor, contrary to assertions made by some other investigators. It is concluded that the OCT can serve as the primary method for assessing the fetal status in pregnancies characterized by placental insufficiency.