Figure 2: A) Bar graph of the stiffness in tension for each construct. B) Bar graph of the load a... more Figure 2: A) Bar graph of the stiffness in tension for each construct. B) Bar graph of the load at two millimeters of displacement (defined as fixation failure) in tension for each construct. Error is reported as the mean plus or minus the standard deviation. The * indicates statistical significance (p < 0.05) when compared to another group. Optimal Fixation for Horizontal Medial Malleolus Fractures Derek F. Amanatullah, Erik McDonald, Adam Shellito, Shain Lafazan, Alejandro Cortes, Shane Curtiss, and Philip R. Wolinsky University of California at Davis School of Medicine, Department of Orthopaedic Surgery, Sacramento, California derek.amanatullah@ucdmc.ucdavis.edu
® Bovine Genome Array Analysis was performed. Data analysis was performed using the dChip MFC App... more ® Bovine Genome Array Analysis was performed. Data analysis was performed using the dChip MFC Application v1.0.0.1. We considered genes in one cartilage zone as elevated if their expression was greater than 2-fold higher than the comparison genes in another cartilage zone. In addition, the elevation was required to be statistically significant (p < 0.05) and non-random via ANOVA analysis (p < 0.01) in both samples of the same zone. The result of the dChip comparison between the gene expression of the superficial and middle zone articular cartilage was input into the Ingenuity Pathway Analysis Software v8.5 to evaluate the changes in canonical signaling pathways as well as any cellular processes and networks involved. Fisher's exact test (p < 0.05) was used to determine statistical significance. Results Affymetrix microarray analysis of superficial and middle zone articular cartilage reveal 52 differentially expressed genes greater than 10-fold and 114 differentially exp...
Anterior femoral notching during total knee arthroplasty is a potential risk factor for periprost... more Anterior femoral notching during total knee arthroplasty is a potential risk factor for periprosthetic supracondylar femur fracture. We conducted a study to determine if the design of the femoral implant changes the risk for periprosthetic supracondylar femur fractures after anterior cortical notching. An anterior cortical defect was created in 12 femoral polyurethane models. Six femora were instrumented with cruciate-retaining implants and 6 with posterior-stabilized implants. Each femur was loaded in external rotation along the anatomical axis. Notch depth and distance from anterior cortical notch to implant were recorded before loading, and fracture pattern was recorded after failure. There were no statistically significant differences in notch depth, distance from notch to implant, torsional stiffness, torque at failure, final torque, or fracture pattern between cruciate-retaining and posterior-stabilized femoral component designs. Periprosthetic fracture after anterior femoral ...
Patients with low-energy hip fractures do not follow the obesity paradox as previously reported. ... more Patients with low-energy hip fractures do not follow the obesity paradox as previously reported. In datasets where injury mechanism is not available, the use of age >50 years (as opposed to commonly used >65 years) as a surrogate for a low-energy hip fracture patients may be a more robust inclusion criterion. In elderly patients with a hip fracture, limited data suggests that obese patients counterintuitively have improved survival compared to normal-weight patients. This "obesity paradox" may be the byproduct of selection bias. We hypothesized that the obesity paradox would not apply to elderly hip fracture patients. The National Surgical Quality Improvement Project dataset identified 71,685 hip fracture patients ≥50 years-of-age with complete body mass index (BMI) data that underwent surgery. Patients were stratified into under and over 75-year-old cohorts (n=18,956 and 52,729, respectively). Within each age group, patients were stratified by BMI class and compared with respect to preoperative characteristics and 30-day mortality. Significant univariate characteristics (p<0.1) were included in multivariate analysis to determine the independent effect of obesity class on 30-day mortality (p<0.05). Multivariate analysis of <75-year-old patients with class-III obesity were more likely to die within 30-days than similarly aged normal-weight patients (OR 1.91, CI 1.06-3.42, p=0.030). Multivariate analysis of ≥75-year-old overweight (OR 0.69, CI 0.62-0.77, p<0.001), class-I obese (OR 0.62, CI 0.51–0.74, p<0.001), or class-II obese (OR=0.69, CI 0.50–0.95, p=0.022) patients were less likely to die within 30-days when compared to similarly aged normal-weight patients. Our data suggest that obesity is a risk factor for mortality in low-energy hip fracture patients, but the appearance of the "obesity paradox" in elderly hip fracture patients results from statistical bias that is only evident upon subgroup analysis.
Concordance, the concept of patients having shared demographic/socioeconomic characteristics with... more Concordance, the concept of patients having shared demographic/socioeconomic characteristics with their physicians, has been associated with improved patient satisfaction and outcomes in primary care but has not been studied in subspecialty care. The objective of this study was to investigate whether patients value concordance with their specialty physicians. The authors assessed the importance of concordance in subspecialist care in 2 cohorts of participants. The first cohort consisted of patients seeking care at a multispecialty orthopedic clinic. The second cohort consisted of volunteer participants recruited from an online platform. Each participant completed a survey scored on an ordinal scale which characteristics of their physicians they find important for their primary care physician (PCP) and a specialist. The characteristics included age, sex, ethnicity, sexual orientation, primary language spoken, and religion. The difference in concordance scores for PCPs and specialists were compared with paired t tests with a Bonferroni correction. A total of 118 patients were recruited in clinic, and a total of 982 volunteers were recruited online. In the clinic cohort, the level of importance for patient-physician concordance of age, ethnicity, language, and religion was not significantly different between PCPs and specialists. In the volunteer cohort, the level of importance for concordance of age, sex, national origin, language, and religion was not significantly different between PCPs and specialists. The volunteers recruited online had significantly higher concordance scores than the patients recruited in clinic for most variables. Patients find patient-physician concordance as important in specialty care as they do in primary care. This may have similar effects on patient outcomes in specialty care. [Orthopedics. 2020;43(5):315-319.].
IMPACT: If immune checkpoint blockade increases bacterial clearance with or without antibiotics i... more IMPACT: If immune checkpoint blockade increases bacterial clearance with or without antibiotics in vitro, clinical application would be almost immediate and dramatic creating a seismic shift in the current therapeutic paradigm of periprosthetic joint infection. OBJECTIVES/GOALS: Periprosthetic joint infection (PJI) is a major cause of failure after joint replacement. Currently, the treatment of PJI relies on removing biofilm contaminated implants. Some of the bacteria within biofilm undergo a phenotypic shift becoming small colony variants (SCVs). SCVs induce local immunosuppression through PD-1/L1 signaling. METHODS/STUDY POPULATION: We will infect cultured human macrophages and bone marrow aspirate with stable Staphylococcus aureus SVCs and treat with anti-PD-1 or anti-PD-L1 monoclonal antibodies with and without antibiotics (e.g., gentamycin, cefazolin, vancomycin, rifampicin) and assess the residual bacterial viability. We will utilize multiplexed ion beam imaging to quantify PD...
Increasing rates of infection by antibiotic resistant bacteria have led to a resurgence of intere... more Increasing rates of infection by antibiotic resistant bacteria have led to a resurgence of interest in bacteriophage (phage) therapy. Several phage therapy studies in animals and humans have been completed over the last two decades. We conducted a systematic review of safety and toxicity data associated with phage therapy in both animals and humans reported in English language publications from 2008–2021. Overall, 69 publications met our eligibility criteria including 20 animal studies, 35 clinical case reports or case series, and 14 clinical trials. After summarizing safety and toxicity data from these publications, we discuss potential approaches to optimize safety and toxicity monitoring with the therapeutic use of phage moving forward. In our systematic review of the literature, we found some adverse events associated with phage therapy, but serious events were extremely rare. Comprehensive and standardized reporting of potential toxicities associated with phage therapy has gene...
The anti-inflammatory secretome of mesenchymal stromal cells (MSCs) is lucrative for the treatmen... more The anti-inflammatory secretome of mesenchymal stromal cells (MSCs) is lucrative for the treatment of osteoarthritis (OA), a disease characterized by low-grade inflammation. However, the precise effects of the MSC secretome on patient-derived OA tissue is lacking. To investigate these effects, alginate encapsulated MSCs are co-cultured with patient-derived OA cartilage explants for 8 days. Proteoglycan distribution in OA cartilage explants examined by Safranin O staining is markedly improved when cultured with MSC microbeads as compared to control OA explants cultured alone. Total sulfated glycosaminoglycan (sGAG) content in OA explants is significantly increased upon co-culture with MSC microbeads on day 8. The sGAG released into the culture media is unchanged by the presence of MSC microbeads, suggesting de novo sGAG synthesis in OA explants. Co-culture with MSC microbeads increased the DNA content and Ki67+ cells in OA explants, indicating proliferation. An increase in secreted cytokines IL-10, HGF, and sFAS assessed by multiplex cytokine assay, increased TIMP1 levels, and reduction in percent apoptotic cells in OA explants is noted. Together, data demonstrates that paracrine factors secreted by alginate encapsulated MSCs microbeads in response to OA cartilage, create an anabolic, proliferative, and anti-apoptotic microenvironment inducing endogenous regeneration in clinically relevant, patient-derived OA cartilage.
INTRODUCTION Patient satisfaction has increasingly been used to assess physician performance and ... more INTRODUCTION Patient satisfaction has increasingly been used to assess physician performance and quality of care. Although there is evidence that patient satisfaction is associated with patient-reported health outcomes and communication-related measures, there is debate over the use of patient satisfaction in reimbursement policy. Patient characteristics that influence satisfaction have been studied, but the effects of personal and demographic characteristics of physicians on patient satisfaction have yet to be explored. METHODS Outpatient satisfaction scores from 11,059 patients who rated 25 orthopaedic surgeons from a single institution were studied. In this study, we sought to explore the relationship between nonmodifiable physician characteristics, such as sex and race, and patient satisfaction with outpatient orthopaedic surgery care, as expressed in the Press Ganey Satisfaction Scores. Univariate logistic regression models were used to test the associations between each provider characteristic and patient satisfaction on the Press Ganey patient satisfaction questionnaire. RESULTS Three nonmodifiable physician personal and demographic characteristics were markedly associated with lower patient satisfaction scores across overall satisfaction, communication, and empathy domains: (1) female gender, (2) Asian ethnicity, and (3) being unmarried. Asian ethnicity reduced the odds of receiving a 5-star rating for likelihood to recommend the provider by nearly 40%, but none of these nonmodifiable physician personal and demographic characteristics affected the likelihood to recommend the practice. DISCUSSION Sex, ethnicity, and marital status are nonmodifiable provider characteristics, each associated with markedly lower odds of receiving a 5-star rating on Press Ganey patient satisfaction survey. These data reveal inherent patient biases that negatively affect physician-patient interactions and may exacerbate the lack of diversity in orthopaedic surgery. More research is necessary before using patient satisfaction ratings to evaluate surgeons or as quality measures that affect reimbursement policies.
BACKGROUND There exists a substantial risk of having a perioperative complication after revision ... more BACKGROUND There exists a substantial risk of having a perioperative complication after revision total joint arthroplasty (TJA). The complex shared decision-making between surgeon and patient would benefit from a high-fidelity tool to identify patients at risk for mortality after revision TJA. Therefore, we developed the CARDE-B score. CARDE-B is an acronym for congestive heart failure, albumin or malnutrition (<3.5 mg/dL), renal failure on dialysis, dependence for daily living, elderly (>65 years of age), and body mass index <25 kg/m2. We developed and validated the CARDE-B score to determine the risk of death within 30 days of a revision TJA. METHODS A total of 13,118 revision TJAs (40% hip and 60% knee) from the National Surgical Quality Improvement Program (NSQIP) database were analyzed. A simple 1-point scoring system, CARDE-B, was created for predicting 30-day mortality after revision TJA, based on a logistic regression model. The CARDE-B scoring system assigns 1 point to each criterion in the acronym: congestive heart failure, albumin (<3.5 mg/dL), renal failure on dialysis, dependence for daily living, elderly (>65 years of age), and body mass index of <25 kg/m2. The CARDE-B scoring system was compared with 2 commonly utilized scores: American Society of Anesthesiologists (ASA) physical status classification and the 5-factor modified frailty index (mFI-5). The area under the curve (AUC) was used to assess the accuracy of each model. The Hosmer-Lemeshow test was used to assess goodness of fit. Finally, the Nationwide Inpatient Sample (NIS) was used for external validation of the CARDE-B score in 19,153 patients who underwent revision TJA in 2017. RESULTS Eighty-eight patients (0.7%) did not survive 30 days after revision TJA. The AUC for the logistic regression model was 0.88 in both the derivation and internal validation samples using NSQIP. The predicted probability of 30-day mortality after revision TJA increased stepwise from <0.01% for a CARDE-B score of 0 points to 39% for a CARDE-B score of 5 points. The AUC for the CARDE-B score predicting 30-day mortality after revision TJA was 0.85. This was more accurate (p < 0.001) than the ASA physical status classification (AUC, 0.77) and the mFI-5 (AUC, 0.67). The AUC for the CARDE-B score in the NIS external validation set was 0.75. The Hosmer-Lemeshow p value for goodness of fit was 0.34, indicating goodness of fit in the external validation sample. CONCLUSIONS The CARDE-B score is a simple system that predicts the risk of death within 30 days of a revision TJA, offering surgeons and patients a valuable and validated risk-stratification tool. LEVEL OF EVIDENCE Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.
Prosthetic joint infection (PJI) is a devastating complication after a joint replacement. PJI and... more Prosthetic joint infection (PJI) is a devastating complication after a joint replacement. PJI and its treatment have a high monetary cost, morbidity, and mortality. The lack of success treating PJI with conventional antibiotics alone is related to the presence of bacterial biofilm on medical implants. Consequently, surgical removal of the implant and prolonged intravenous antibiotics to eradicate the infection are necessary prior to re-implanting a new prosthetic joint. Growing clinical data shows that bacterial predators, called bacteriophages (phages), could be an alternative treatment strategy or prophylactic approach for PJI. Phages could further be exploited to degrade biofilms, making bacteria more susceptible to antibiotics and enabling potential combinatorial therapies. Emerging research suggests that phages may also directly interact with the innate immune response. Phage therapy may play an important, and currently understudied, role in the clearance of PJI, and has the po...
Computer-assisted orthopedic surgery improves mechanical alignment and the accuracy of surgical c... more Computer-assisted orthopedic surgery improves mechanical alignment and the accuracy of surgical cuts in the context of total knee arthroplasty (TKA). A simplified, navigation-enhanced instrumentation system was assessed to determine whether the same effects could be achieved with a less intrusive system. Two cohorts of surgeons (experienced and trainees) performed a series of TKA cuts using models with and without navigation-enhanced instrumentation. The accuracy of each system was determined via the rate of outliers, measured as any cut that deviated from the planned cut by more than 2° or 2 mm. The effect of experience level was limited, with only the outlier rate for tibial varus or valgus measurement showing a significant difference between user groups with conventional instrumentation (P=.004). The use of navigation-enhanced instrumentation significantly reduced the total outlier rate compared with conventional instrumentation from 35% to 4% for experienced users (P<.001) and from 34% to 10% for trainees (P<.001). These results suggest that navigation-enhanced instrumentation is a viable alternative to conventional instrumentation to reduce outlier rates and improve cut accuracy. This trial also showed that additional experience may not correlate with improved surgical accuracy. Outliers may not reflect individual surgical ability as much as limitations of the instrumentation or other unidentified factors. [Orthopedics. 2021;44(x):xx-xx.].
BACKGROUND Piriformis-sparing approaches to the hip allow surgeons to avoid releasing the pirifor... more BACKGROUND Piriformis-sparing approaches to the hip allow surgeons to avoid releasing the piriformis tendon during total hip arthroplasty; however, the consequences of retracting an intact piriformis tendon during such an approach remain ill-defined. The present study aimed to determine the upper limit of force that can be applied during retraction of the piriformis tendon to expose the hip, and to quantify the resultant damage to the piriformis musculotendinous complex. METHODS A patent-pending instrumented retractor was designed to record the applied force, duration, and angle of retraction during a piriformis-sparing posterior approach to the hip. In addition to the data collected with use of the instrumented retractor, damage to the piriformis muscle and tendon was quantified by a blinded observer. RESULTS There was no damage to the piriformis tendon in 22 (96%) of 23 hips during piriformis retraction for visualization of the hip capsule; however, there was complete or partial damage to the piriformis muscle at the sacral origin, belly, or musculotendinous junction (i.e., outside the surgical field) noted in 21 (91%) of 23 hips. The mean peak force to failure of the piriformis muscle was exceedingly small (29.0 ± 9.4 N; range, 10.1 to 44.9 N). CONCLUSIONS The mean peak force applied to the piriformis retractor is much less than the force required for several common daily activities, such as opening a door or crushing an empty aluminum can. Soft-tissue damage that occurs outside the surgical field during the retraction of unreleased muscles, like the piriformis muscle, is common and remains an uncontrolled surgical variable. This inadvertent soft-tissue damage is not routinely accounted for when accessing the invasiveness of a procedure. Hence, it is no longer adequate to define a minimally invasive surgical procedure simply as an approach that involves the limited release of anatomical structures. CLINICAL RELEVANCE The use of instrumented retractors may redefine surgical invasiveness by providing data that could alter our understanding of the soft-tissue damage caused by retraction and open the possibility of robot-assisted or damage-limiting retractor systems.
Figure 2: A) Bar graph of the stiffness in tension for each construct. B) Bar graph of the load a... more Figure 2: A) Bar graph of the stiffness in tension for each construct. B) Bar graph of the load at two millimeters of displacement (defined as fixation failure) in tension for each construct. Error is reported as the mean plus or minus the standard deviation. The * indicates statistical significance (p < 0.05) when compared to another group. Optimal Fixation for Horizontal Medial Malleolus Fractures Derek F. Amanatullah, Erik McDonald, Adam Shellito, Shain Lafazan, Alejandro Cortes, Shane Curtiss, and Philip R. Wolinsky University of California at Davis School of Medicine, Department of Orthopaedic Surgery, Sacramento, California derek.amanatullah@ucdmc.ucdavis.edu
® Bovine Genome Array Analysis was performed. Data analysis was performed using the dChip MFC App... more ® Bovine Genome Array Analysis was performed. Data analysis was performed using the dChip MFC Application v1.0.0.1. We considered genes in one cartilage zone as elevated if their expression was greater than 2-fold higher than the comparison genes in another cartilage zone. In addition, the elevation was required to be statistically significant (p < 0.05) and non-random via ANOVA analysis (p < 0.01) in both samples of the same zone. The result of the dChip comparison between the gene expression of the superficial and middle zone articular cartilage was input into the Ingenuity Pathway Analysis Software v8.5 to evaluate the changes in canonical signaling pathways as well as any cellular processes and networks involved. Fisher's exact test (p < 0.05) was used to determine statistical significance. Results Affymetrix microarray analysis of superficial and middle zone articular cartilage reveal 52 differentially expressed genes greater than 10-fold and 114 differentially exp...
Anterior femoral notching during total knee arthroplasty is a potential risk factor for periprost... more Anterior femoral notching during total knee arthroplasty is a potential risk factor for periprosthetic supracondylar femur fracture. We conducted a study to determine if the design of the femoral implant changes the risk for periprosthetic supracondylar femur fractures after anterior cortical notching. An anterior cortical defect was created in 12 femoral polyurethane models. Six femora were instrumented with cruciate-retaining implants and 6 with posterior-stabilized implants. Each femur was loaded in external rotation along the anatomical axis. Notch depth and distance from anterior cortical notch to implant were recorded before loading, and fracture pattern was recorded after failure. There were no statistically significant differences in notch depth, distance from notch to implant, torsional stiffness, torque at failure, final torque, or fracture pattern between cruciate-retaining and posterior-stabilized femoral component designs. Periprosthetic fracture after anterior femoral ...
Patients with low-energy hip fractures do not follow the obesity paradox as previously reported. ... more Patients with low-energy hip fractures do not follow the obesity paradox as previously reported. In datasets where injury mechanism is not available, the use of age >50 years (as opposed to commonly used >65 years) as a surrogate for a low-energy hip fracture patients may be a more robust inclusion criterion. In elderly patients with a hip fracture, limited data suggests that obese patients counterintuitively have improved survival compared to normal-weight patients. This "obesity paradox" may be the byproduct of selection bias. We hypothesized that the obesity paradox would not apply to elderly hip fracture patients. The National Surgical Quality Improvement Project dataset identified 71,685 hip fracture patients ≥50 years-of-age with complete body mass index (BMI) data that underwent surgery. Patients were stratified into under and over 75-year-old cohorts (n=18,956 and 52,729, respectively). Within each age group, patients were stratified by BMI class and compared with respect to preoperative characteristics and 30-day mortality. Significant univariate characteristics (p<0.1) were included in multivariate analysis to determine the independent effect of obesity class on 30-day mortality (p<0.05). Multivariate analysis of <75-year-old patients with class-III obesity were more likely to die within 30-days than similarly aged normal-weight patients (OR 1.91, CI 1.06-3.42, p=0.030). Multivariate analysis of ≥75-year-old overweight (OR 0.69, CI 0.62-0.77, p<0.001), class-I obese (OR 0.62, CI 0.51–0.74, p<0.001), or class-II obese (OR=0.69, CI 0.50–0.95, p=0.022) patients were less likely to die within 30-days when compared to similarly aged normal-weight patients. Our data suggest that obesity is a risk factor for mortality in low-energy hip fracture patients, but the appearance of the "obesity paradox" in elderly hip fracture patients results from statistical bias that is only evident upon subgroup analysis.
Concordance, the concept of patients having shared demographic/socioeconomic characteristics with... more Concordance, the concept of patients having shared demographic/socioeconomic characteristics with their physicians, has been associated with improved patient satisfaction and outcomes in primary care but has not been studied in subspecialty care. The objective of this study was to investigate whether patients value concordance with their specialty physicians. The authors assessed the importance of concordance in subspecialist care in 2 cohorts of participants. The first cohort consisted of patients seeking care at a multispecialty orthopedic clinic. The second cohort consisted of volunteer participants recruited from an online platform. Each participant completed a survey scored on an ordinal scale which characteristics of their physicians they find important for their primary care physician (PCP) and a specialist. The characteristics included age, sex, ethnicity, sexual orientation, primary language spoken, and religion. The difference in concordance scores for PCPs and specialists were compared with paired t tests with a Bonferroni correction. A total of 118 patients were recruited in clinic, and a total of 982 volunteers were recruited online. In the clinic cohort, the level of importance for patient-physician concordance of age, ethnicity, language, and religion was not significantly different between PCPs and specialists. In the volunteer cohort, the level of importance for concordance of age, sex, national origin, language, and religion was not significantly different between PCPs and specialists. The volunteers recruited online had significantly higher concordance scores than the patients recruited in clinic for most variables. Patients find patient-physician concordance as important in specialty care as they do in primary care. This may have similar effects on patient outcomes in specialty care. [Orthopedics. 2020;43(5):315-319.].
IMPACT: If immune checkpoint blockade increases bacterial clearance with or without antibiotics i... more IMPACT: If immune checkpoint blockade increases bacterial clearance with or without antibiotics in vitro, clinical application would be almost immediate and dramatic creating a seismic shift in the current therapeutic paradigm of periprosthetic joint infection. OBJECTIVES/GOALS: Periprosthetic joint infection (PJI) is a major cause of failure after joint replacement. Currently, the treatment of PJI relies on removing biofilm contaminated implants. Some of the bacteria within biofilm undergo a phenotypic shift becoming small colony variants (SCVs). SCVs induce local immunosuppression through PD-1/L1 signaling. METHODS/STUDY POPULATION: We will infect cultured human macrophages and bone marrow aspirate with stable Staphylococcus aureus SVCs and treat with anti-PD-1 or anti-PD-L1 monoclonal antibodies with and without antibiotics (e.g., gentamycin, cefazolin, vancomycin, rifampicin) and assess the residual bacterial viability. We will utilize multiplexed ion beam imaging to quantify PD...
Increasing rates of infection by antibiotic resistant bacteria have led to a resurgence of intere... more Increasing rates of infection by antibiotic resistant bacteria have led to a resurgence of interest in bacteriophage (phage) therapy. Several phage therapy studies in animals and humans have been completed over the last two decades. We conducted a systematic review of safety and toxicity data associated with phage therapy in both animals and humans reported in English language publications from 2008–2021. Overall, 69 publications met our eligibility criteria including 20 animal studies, 35 clinical case reports or case series, and 14 clinical trials. After summarizing safety and toxicity data from these publications, we discuss potential approaches to optimize safety and toxicity monitoring with the therapeutic use of phage moving forward. In our systematic review of the literature, we found some adverse events associated with phage therapy, but serious events were extremely rare. Comprehensive and standardized reporting of potential toxicities associated with phage therapy has gene...
The anti-inflammatory secretome of mesenchymal stromal cells (MSCs) is lucrative for the treatmen... more The anti-inflammatory secretome of mesenchymal stromal cells (MSCs) is lucrative for the treatment of osteoarthritis (OA), a disease characterized by low-grade inflammation. However, the precise effects of the MSC secretome on patient-derived OA tissue is lacking. To investigate these effects, alginate encapsulated MSCs are co-cultured with patient-derived OA cartilage explants for 8 days. Proteoglycan distribution in OA cartilage explants examined by Safranin O staining is markedly improved when cultured with MSC microbeads as compared to control OA explants cultured alone. Total sulfated glycosaminoglycan (sGAG) content in OA explants is significantly increased upon co-culture with MSC microbeads on day 8. The sGAG released into the culture media is unchanged by the presence of MSC microbeads, suggesting de novo sGAG synthesis in OA explants. Co-culture with MSC microbeads increased the DNA content and Ki67+ cells in OA explants, indicating proliferation. An increase in secreted cytokines IL-10, HGF, and sFAS assessed by multiplex cytokine assay, increased TIMP1 levels, and reduction in percent apoptotic cells in OA explants is noted. Together, data demonstrates that paracrine factors secreted by alginate encapsulated MSCs microbeads in response to OA cartilage, create an anabolic, proliferative, and anti-apoptotic microenvironment inducing endogenous regeneration in clinically relevant, patient-derived OA cartilage.
INTRODUCTION Patient satisfaction has increasingly been used to assess physician performance and ... more INTRODUCTION Patient satisfaction has increasingly been used to assess physician performance and quality of care. Although there is evidence that patient satisfaction is associated with patient-reported health outcomes and communication-related measures, there is debate over the use of patient satisfaction in reimbursement policy. Patient characteristics that influence satisfaction have been studied, but the effects of personal and demographic characteristics of physicians on patient satisfaction have yet to be explored. METHODS Outpatient satisfaction scores from 11,059 patients who rated 25 orthopaedic surgeons from a single institution were studied. In this study, we sought to explore the relationship between nonmodifiable physician characteristics, such as sex and race, and patient satisfaction with outpatient orthopaedic surgery care, as expressed in the Press Ganey Satisfaction Scores. Univariate logistic regression models were used to test the associations between each provider characteristic and patient satisfaction on the Press Ganey patient satisfaction questionnaire. RESULTS Three nonmodifiable physician personal and demographic characteristics were markedly associated with lower patient satisfaction scores across overall satisfaction, communication, and empathy domains: (1) female gender, (2) Asian ethnicity, and (3) being unmarried. Asian ethnicity reduced the odds of receiving a 5-star rating for likelihood to recommend the provider by nearly 40%, but none of these nonmodifiable physician personal and demographic characteristics affected the likelihood to recommend the practice. DISCUSSION Sex, ethnicity, and marital status are nonmodifiable provider characteristics, each associated with markedly lower odds of receiving a 5-star rating on Press Ganey patient satisfaction survey. These data reveal inherent patient biases that negatively affect physician-patient interactions and may exacerbate the lack of diversity in orthopaedic surgery. More research is necessary before using patient satisfaction ratings to evaluate surgeons or as quality measures that affect reimbursement policies.
BACKGROUND There exists a substantial risk of having a perioperative complication after revision ... more BACKGROUND There exists a substantial risk of having a perioperative complication after revision total joint arthroplasty (TJA). The complex shared decision-making between surgeon and patient would benefit from a high-fidelity tool to identify patients at risk for mortality after revision TJA. Therefore, we developed the CARDE-B score. CARDE-B is an acronym for congestive heart failure, albumin or malnutrition (<3.5 mg/dL), renal failure on dialysis, dependence for daily living, elderly (>65 years of age), and body mass index <25 kg/m2. We developed and validated the CARDE-B score to determine the risk of death within 30 days of a revision TJA. METHODS A total of 13,118 revision TJAs (40% hip and 60% knee) from the National Surgical Quality Improvement Program (NSQIP) database were analyzed. A simple 1-point scoring system, CARDE-B, was created for predicting 30-day mortality after revision TJA, based on a logistic regression model. The CARDE-B scoring system assigns 1 point to each criterion in the acronym: congestive heart failure, albumin (<3.5 mg/dL), renal failure on dialysis, dependence for daily living, elderly (>65 years of age), and body mass index of <25 kg/m2. The CARDE-B scoring system was compared with 2 commonly utilized scores: American Society of Anesthesiologists (ASA) physical status classification and the 5-factor modified frailty index (mFI-5). The area under the curve (AUC) was used to assess the accuracy of each model. The Hosmer-Lemeshow test was used to assess goodness of fit. Finally, the Nationwide Inpatient Sample (NIS) was used for external validation of the CARDE-B score in 19,153 patients who underwent revision TJA in 2017. RESULTS Eighty-eight patients (0.7%) did not survive 30 days after revision TJA. The AUC for the logistic regression model was 0.88 in both the derivation and internal validation samples using NSQIP. The predicted probability of 30-day mortality after revision TJA increased stepwise from <0.01% for a CARDE-B score of 0 points to 39% for a CARDE-B score of 5 points. The AUC for the CARDE-B score predicting 30-day mortality after revision TJA was 0.85. This was more accurate (p < 0.001) than the ASA physical status classification (AUC, 0.77) and the mFI-5 (AUC, 0.67). The AUC for the CARDE-B score in the NIS external validation set was 0.75. The Hosmer-Lemeshow p value for goodness of fit was 0.34, indicating goodness of fit in the external validation sample. CONCLUSIONS The CARDE-B score is a simple system that predicts the risk of death within 30 days of a revision TJA, offering surgeons and patients a valuable and validated risk-stratification tool. LEVEL OF EVIDENCE Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.
Prosthetic joint infection (PJI) is a devastating complication after a joint replacement. PJI and... more Prosthetic joint infection (PJI) is a devastating complication after a joint replacement. PJI and its treatment have a high monetary cost, morbidity, and mortality. The lack of success treating PJI with conventional antibiotics alone is related to the presence of bacterial biofilm on medical implants. Consequently, surgical removal of the implant and prolonged intravenous antibiotics to eradicate the infection are necessary prior to re-implanting a new prosthetic joint. Growing clinical data shows that bacterial predators, called bacteriophages (phages), could be an alternative treatment strategy or prophylactic approach for PJI. Phages could further be exploited to degrade biofilms, making bacteria more susceptible to antibiotics and enabling potential combinatorial therapies. Emerging research suggests that phages may also directly interact with the innate immune response. Phage therapy may play an important, and currently understudied, role in the clearance of PJI, and has the po...
Computer-assisted orthopedic surgery improves mechanical alignment and the accuracy of surgical c... more Computer-assisted orthopedic surgery improves mechanical alignment and the accuracy of surgical cuts in the context of total knee arthroplasty (TKA). A simplified, navigation-enhanced instrumentation system was assessed to determine whether the same effects could be achieved with a less intrusive system. Two cohorts of surgeons (experienced and trainees) performed a series of TKA cuts using models with and without navigation-enhanced instrumentation. The accuracy of each system was determined via the rate of outliers, measured as any cut that deviated from the planned cut by more than 2° or 2 mm. The effect of experience level was limited, with only the outlier rate for tibial varus or valgus measurement showing a significant difference between user groups with conventional instrumentation (P=.004). The use of navigation-enhanced instrumentation significantly reduced the total outlier rate compared with conventional instrumentation from 35% to 4% for experienced users (P<.001) and from 34% to 10% for trainees (P<.001). These results suggest that navigation-enhanced instrumentation is a viable alternative to conventional instrumentation to reduce outlier rates and improve cut accuracy. This trial also showed that additional experience may not correlate with improved surgical accuracy. Outliers may not reflect individual surgical ability as much as limitations of the instrumentation or other unidentified factors. [Orthopedics. 2021;44(x):xx-xx.].
BACKGROUND Piriformis-sparing approaches to the hip allow surgeons to avoid releasing the pirifor... more BACKGROUND Piriformis-sparing approaches to the hip allow surgeons to avoid releasing the piriformis tendon during total hip arthroplasty; however, the consequences of retracting an intact piriformis tendon during such an approach remain ill-defined. The present study aimed to determine the upper limit of force that can be applied during retraction of the piriformis tendon to expose the hip, and to quantify the resultant damage to the piriformis musculotendinous complex. METHODS A patent-pending instrumented retractor was designed to record the applied force, duration, and angle of retraction during a piriformis-sparing posterior approach to the hip. In addition to the data collected with use of the instrumented retractor, damage to the piriformis muscle and tendon was quantified by a blinded observer. RESULTS There was no damage to the piriformis tendon in 22 (96%) of 23 hips during piriformis retraction for visualization of the hip capsule; however, there was complete or partial damage to the piriformis muscle at the sacral origin, belly, or musculotendinous junction (i.e., outside the surgical field) noted in 21 (91%) of 23 hips. The mean peak force to failure of the piriformis muscle was exceedingly small (29.0 ± 9.4 N; range, 10.1 to 44.9 N). CONCLUSIONS The mean peak force applied to the piriformis retractor is much less than the force required for several common daily activities, such as opening a door or crushing an empty aluminum can. Soft-tissue damage that occurs outside the surgical field during the retraction of unreleased muscles, like the piriformis muscle, is common and remains an uncontrolled surgical variable. This inadvertent soft-tissue damage is not routinely accounted for when accessing the invasiveness of a procedure. Hence, it is no longer adequate to define a minimally invasive surgical procedure simply as an approach that involves the limited release of anatomical structures. CLINICAL RELEVANCE The use of instrumented retractors may redefine surgical invasiveness by providing data that could alter our understanding of the soft-tissue damage caused by retraction and open the possibility of robot-assisted or damage-limiting retractor systems.
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Papers by Derek Amanatullah