Association Between Periprosthetic Joint Infection and Mortality Following Primary Total Hip Arthroplasty.

BACKGROUND: Periprosthetic joint infection (PJI) remains a dreaded and unpredictable complication after total hip arthroplasty (THA). In addition to causing substantial morbidity, PJI may contribute to long-term mortality risk. Our objective was to determine the long-term mortality risk associated with PJI following THA. METHODS: This population-based, retrospective cohort study included adult patients (≥18 years old) in Ontario, Canada, who underwent their first primary elective THA for arthritis between April 1, 2002, and March 31, 2021. The primary outcome was death within 10 years after the index THA. Mortality was compared between propensity-score-matched groups (PJI within 1 year after surgery versus no PJI within 1 year after surgery) with use of survival analyses. Patients who died within 1 year after surgery were excluded to avoid immortal time bias. RESULTS: A total of 175,432 patients (95,883 [54.7%] women) with a mean age (and standard deviation) of 67 ± 11.4 years underwent primary THA during the study period. Of these, 868 patients (0.49%) underwent surgery for a PJI of the replaced joint within 1 year after the index procedure. After matching, patients with a PJI within the first year had a significantly higher 10-year mortality rate than their counterparts (11.4% [94 of 827 patients] versus 2.2% [18 of 827 patients]; absolute risk difference, 9.19% [95% confidence interval (CI), 6.81% to 11.6%]; hazard ratio, 5.49 [95% CI, 3.32 to 9.09]). CONCLUSIONS: PJI within 1 year after surgery is associated with over a fivefold increased risk of mortality within 10 years. The findings of this study underscore the importance of prioritizing efforts related to the prevention, diagnosis, and treatment of PJIs. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Effect of Depression Interventions in Patients Undergoing Total Joint Arthroplasty Without a Formal Diagnosis of Depression: A Systematic Review.

PURPOSE: Depression is a notable contributor to suboptimal outcomes after total joint arthroplasty (TJA). We conducted a systematic review of comparative studies to review the available evidence of interventions that affected depression scores and/or outcomes for patients undergoing TJA. METHODS: EMBASE, Ovid MEDLINE, PubMed, and Scopus were reviewed systematically from inception until November 15, 2022. Studies that were relevant for this review included comparative studies between patients who received an intervention within 3 months before or after their primary total hip or knee arthroplasty procedure. The interventions included a wide range of modalities, which were grouped into psychotherapy, enhanced perioperative support, and pharmacotherapy. Other interventions included physiotherapy techniques with a psychological focus, art/music-based therapy, occupational therapy support, and educational interventions. Meta-analysis was conducted for psychotherapy and enhanced support. RESULTS: The final systematic review consisted of 28 relevant studies, most of which were randomized controlled trials. A total of 3,702 patients, with a mean age of 66 years, were considered, of whom 59% were female. Most of the studies reported a notable reduction in depressive symptoms and/or scores based on the interventions being analyzed. At 3 months postoperatively, psychotherapy and enhanced support both resulted in markedly better depression and function scores compared with control subjects, with psychotherapy additionally improving pain scores. CONCLUSIONS: Overall, a wide range of interventions aimed at psychological optimization of patients undergoing TJA can improve depressive symptoms, pain, and function, even in the absence of a formal diagnosis of depression. Specifically, cognitive-based psychotherapy and enhanced perioperative support had the best evidence. Routine pharmacotherapy plays a limited role, if any, in the care of TJA. Additional efforts to develop pragmatic, evidence-based, and reproducible interventions are warranted to continue to optimize outcomes in TJA patients.

In-hospital outcomes following primary and revision total hip arthroplasty in nonagenarian patients.

PURPOSE: The primary goal of this study was to assess the risk of postoperative surgical and medical complications and problems among nonagenarian patients operated with hip arthroplasty. METHODS: Data from a specific high-volume arthroplasty clinic, were collected to evaluate postoperative morbidity and complication rates after hip arthroplasty in nonagenarians, compared with a control group of younger, but similar patients. Outcomes evaluated included length of stay, transfusion rate, and postoperative medical and surgical complication rates. RESULTS: A total of 97 nonagenarian patients (mean age 91.4 years) were included, and compared with 89 control group patients (mean age 70.18 years). Nonagenarian patients had significantly longer length of stay (11.44 vs. 7.98 days, p < 0.01), significantly higher risk of needing a transfusion (11.30% vs. 3.40%, p = 0.04), and significantly higher risk of a postoperative medical complication (28.90% vs. 11.20%, p = 0.03). There was no difference in postoperative surgical complication rate (7.20% vs. 2.20%, p = 0.12). CONCLUSION: Nonagenarian patients, when compared to a younger control group, experience significantly longer hospital stays, and risk of non-surgical complications. Arthroplasty in nonagenarian patients carries with it a high risk of complications, and thus careful pre-operative evaluation and the care of these patients at high volume, specialized clinics is important to optimize outcomes. LEVEL OF EVIDENCE: Level III retrospective cohort analysis.

Virtual versus in-person physiotherapy following total knee arthroplasty: a comparative analysis.

PURPOSE: At our centre, we developed and implemented a video-based post-operative physiotherapy program for patients undergoing total knee arthroplasty (TKA). Our aims were to analyse and compare the outcomes of this program to in-person physiotherapy. METHODS: We reviewed the outcomes of 112 patients and captured range-of-motion (ROM) measurements and pain scores (P4 questionnaire). We compared the outcomes to a cohort of 175 patients undergoing in-person therapy. Comparative analysis was performed using a two-tailed Student's t-test. RESULTS: There was no significant difference between the two groups in age, sex, or initial post-operative knee ROM. On discharge from virtual physiotherapy, mean flexion was 122.6° (SD 7.6). There was no significant difference in improvement in knee flexion between the virtual and in-person groups (mean 30.6° vs 34.0°, p = 0.07). There was no significant difference in the proportion of patients achieving ≥ 120° of flexion (85.0% virtual vs 91.3% in-person, p = 0.11) or those achieving an extension deficit of ≤ 5° (96.0% vs 98.3%, p = 0.25). There was no difference in the number of PT visits to discharge (10.5 vs 11.1, p = 0.14) or final pain scores (12.4 vs 11.9, p = 0.61). CONCLUSION: Improvements in knee ROM measures are comparable between virtual and in-person physiotherapy with both groups achieving a good functional range. These findings have implications for the virtual delivery of healthcare, especially among remote populations and patients with mobility limitations.

Impact of the coronavirus disease 2019 pandemic on equity of access to hip and knee replacements: a population-level study.

PURPOSE: The COVID-19 pandemic had innumerable impacts on healthcare delivery. In Canada, this included limitations on inpatient capacity, which resulted in an increased focus on outpatient surgery for non-emergent cases such as joint replacements. The objective of this study was to assess whether the pandemic and the shift towards outpatient surgery had an impact on access to joint replacement for marginalized patients. METHODS: Data from Ontario's administrative healthcare databases were obtained for all patients undergoing an elective hip or knee replacement between January 1, 2018 and August 31, 2021. All surgeries performed before March 15, 2020 were classified as "pre-COVID," while all procedures performed after that date were classified as "post-COVID." The Ontario Marginalization Index domains were used to analyze proportion of marginalized patients undergoing surgery pre- and post-COVID. RESULTS: A total of 102,743 patients were included-42,812 hip replacements and 59,931 knee replacements. There was a significant shift towards outpatient surgery during the post-COVID period (1.1% of all cases pre-COVID to 13.2% post-COVID, p < 0.001). In the post-COVID cohort, there were significantly fewer patients from some marginalized groups, as well as fewer patients with certain co-morbidities, such as congestive heart failure and chronic obstructive pulmonary disease. CONCLUSION: The most important finding of this population-level database study is that, compared to before the COVID-19 pandemic, there has been a change in the profile of patients undergoing hip and knee replacements in Ontario, specifically across a range of indicators. Fewer marginalized patients are undergoing joint replacement surgery since the COVID-19 pandemic. Further monitoring of access to joint replacement surgery is required in order to ensure that surgery is provided to those who are most in need.

Treatment of Concurrent Depression and Its Effect on Outcomes After Total Joint Arthroplasty: A Systematic Review of Comparative Studies.

PURPOSE: There is a growing body of evidence suggesting that patients with a diagnosis of depression suffer worse outcomes after total joint arthroplasty (TJA) procedures. It is unclear whether depression treatment is a modifiable risk factor that can be targeted to improve suboptimal outcomes. We conducted a systematic review to understand the role that various interventions have on outcomes of TJA in patients with diagnosed depression (PDDs). METHODS: PubMed, Ovid MEDLINE, Scopus, and EMBASE were searched systematically from inception until November 2022. Studies of PDDs who underwent TJA that compared any intervention/treatment of depression with a control group and reported pain, functional outcomes, depression scores, and/or revision rates after TJA were relevant for this review. RESULTS: Ten relevant studies were included in the final systematic review, with a total of 33,501 patients included. Two studies reported lower revision rates for patients receiving selective serotonin reuptake inhibitor treatment and psychotherapy. Two studies showed no difference in functional outcomes for patients receiving pharmacologic treatment. One study reported improved functional outcomes for patients receiving cognitive behavioral therapy and another reported improved postoperative functional outcomes for patients receiving alprazolam. CONCLUSION: Interventions targeted at PDDs may improve short-term pain and functional outcomes, and there may be an association between selective serotonin reuptake inhibitor use and implant survival. The current literature is limited and inconclusive, with important gaps in understanding regarding the optimization and treatment of this modifiable risk factor. Surgeons should consider depression treatment as a method to improve outcomes in this cohort.

Management of Greater Trochanteric Pain Syndrome After Total Hip Arthroplasty: Practice Patterns and Surgeon Attitudes.

INTRODUCTION: Greater trochanteric pain syndrome (GTPS) or trochanteric bursitis is described as pain on the lateral side of the hip that does not involve the hip joint and can be elicited clinically by palpation over the greater trochanter. To date, there remains no consensus on clinical guidelines for either diagnosis or management of GTPS. METHODS: To understand the practice patterns, beliefs, and attitudes relating to the management of GTPS after total hip arthroplasty, a survey was developed and completed by Canadian arthroplasty surgeons. The final survey consisted of 23 questions divided into three sections: 1) screening questions; 2) demographic information; and 3) practice patterns, attitudes, and beliefs. RESULTS: Most surgeons use physical examination alone for diagnosis. A detailed analysis indicates that surgeons primarily treat GTPS with oral anti-inflammatories (57.1%), structured physiotherapy (52.4%), and steroid injections (45.2%). Management options are typically nonsurgical and comprise a combination of either unstructured or targeted physiotherapy, corticosteroid injections, or platelet-rich plasma. DISCUSSION: There remains an absence of clinical consensus for the diagnosis and management of GTPS after total hip arthroplasty. Physical examination is most often relied on, regardless of the availability of imaging aids. While common treatments of GTPS were identified, up to one-third of patients fail initial therapy.

Arthroscopy Association of Canada Position Statement on Opioid Prescription After Arthroscopic Surgery.

Background: Despite the ongoing opioid epidemic, most patients are still prescribed a significant number of opioid medications for pain management after arthroscopic surgery. There is a need for consensus among orthopaedic surgeons and solutions to aid providers in analgesic strategies that reduce the use of opioid pain medications. Purpose: This position statement was developed with a comprehensive systematic review and meta-analysis of exclusively randomized controlled trials (RCTs) to synthesize the best available evidence for managing acute postoperative pain after arthroscopic surgery. Study Design: Position statement. Methods: The Embase, MEDLINE, PubMed, Scopus, and Web of Science databases were searched from inception until August 10, 2022. Keywords included arthroscopy, opioids, analgesia, and pain, and associated variations. We included exclusively RCTs on adult patients to gather the best available evidence for managing acute postoperative pain after arthroscopic surgery. Patient characteristics, pain, and opioid data were extracted, data were analyzed, and trial bias was evaluated. Results: A total of 21 RCTs were identified related to the prescription of opioid-sparing pain medication after arthroscopic surgery. The following recommendations regarding noninvasive, postoperative pain management strategies were made: (1) multimodal oral nonopioid analgesic regimens-including at least 1 of acetaminophen-a nonsteroidal anti-inflammatory drug-can significantly reduce opioid consumption with no change in pain scores; (2) cryotherapy is likely to help with pain management, although the evidence on the optimal method of application (continuous-flow vs ice pack application) is unclear; (3) and (4) limited RCT evidence supports the efficacy of transcutaneous electrical nerve stimulation and relaxation exercises in reducing opioid consumption after arthroscopy; and (5) limited RCT evidence exists against the efficacy of transdermal lidocaine patches in reducing opioid consumption. Conclusion: A range of nonopioid strategies exist that can reduce postarthroscopic procedural opioid consumption with equivalent vocal pain outcomes. Optimal strategies include multimodal analgesia with education and restricted/reduced opioid prescription.

Overcoming the Barriers to Diversity in Orthopaedic Surgery: A Global Perspective.

BACKGROUND: Diversity in orthopaedics continues to lag behind that in other surgical specialties. This pattern exists globally and is not unique to gender or race. This review offers a global perspective on overcoming the barriers to diversity in orthopaedics. METHODS: A literature search of MEDLINE and Embase was conducted and a narrative review was undertaken. Publications that discussed any aspect of diversity or solutions to diversity within orthopaedics or academic orthopaedics were identified. RESULTS: A total of 62 studies were included. Studies showed that diversity in orthopaedic training is limited by structural barriers such as long hours, requirements to relocate during training, training inflexibility, and a lack of exposure to orthopaedics. Implicit bias during the selection process for training, discrimination, and a lack of role models are additional barriers that are experienced by both minority and female surgeons. The global lack of diversity suggests that there are also inherent "cultural barriers" that are unique to orthopaedics; however, these barriers are not uniformly experienced. Perceptions of orthopaedics as promoting an unhealthy work-life balance and the existence of a "boys' club" must be addressed. Strong, committed leaders can embed cultural norms, support trainees, and act as visible role models. Targeted efforts to increase diverse recruitment and to reduce bias in selection processes for medical school and specialty training will increase diversity in the "training pipeline." CONCLUSIONS: Diversity in orthopaedics continues to lag behind that in other specialties. Increasing diversity is important for providing a more inclusive training environment, improving patient care, and reducing health disparities. Structural and cultural barriers need to be addressed to improve diversity in orthopaedics. Promoting a culture supportive of all surgeons is essential to reframing perceptions that may prevent individuals from even considering a career as an orthopaedic surgeon. Changing attitudes require focused efforts from committed leadership in a "top-down" approach that prioritizes diversity. The efforts from national bodies seeking to tackle the lack of diversity, as well as the establishment of organizations committed to diversity, such as the International Orthopaedic Diversity Alliance, provide reasons to be optimistic for the future.

Understanding the Learning Curve of Carpal Tunnel Release With Ultrasound Guidance: A Review.

Carpal tunnel syndrome (CTS) is the most common compressive neuropathy and can be treated through carpal tunnel release (CTR) if nonoperative treatments fail. CTR can be performed through a variety of techniques, including traditional open, mini-open, endoscopic, and CTR with ultrasound guidance (CTR-US). The evidence on endoscopic CTR is mixed, due to a higher potential for nerve injury with endoscopic CTR compared to traditional open CTR. CTR-US offers the potential advantage of allowing the visualization of all key anatomical structures, combined with a very small incision and minimal soft tissue insult. As with any ultrasonographic technique or procedure, the learning curve needs to be considered for any provider considering adopting CTR-US. However, literature on ultrasound use around the wrist, including early evidence on the learning curve of CTR-US specifically, demonstrates this skill can be learned relatively quickly by providers with a wide range of prior experience in ultrasound and CTR. Overall, there is a need for high-quality studies comparing different CTR techniques, particularly CTR-US, as it offers the potential for considerable cost savings.

Opioid-Sparing Strategies in Arthroscopic Surgery: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

BACKGROUND: Opioid overprescription is a problem in orthopaedic surgery. Arthroscopic surgery, given its minimally invasive nature, represents an opportunity to minimize opioid prescription and consumption by using effective pain management adjuncts. Thus, the primary question posed in this study was which noninvasive pain management modalities can effectively manage pain and reduce opioid intake after arthroscopic surgery. METHODS: The databases PubMed, MEDLINE, EMBASE, Scopus, and Web of Science were searched on August 10, 2022. Randomized controlled trials (RCTs) evaluating noninvasive pain management strategies in arthroscopy patients were evaluated. Eligible studies were selected through a systematic screening process. Meta-analysis was performed for pain scores and opioid consumption at time points which had sufficient data available. RESULTS: Twenty-one RCTs were included, with a total of 2,148 patients undergoing shoulder, knee, and hip arthroscopy. Meta-analysis comparing nonopioid, oral analgesic regimens, with or without patient education components, with the standard of care or placebo demonstrated no difference in pain scores at 24 hours, 4 to 7 days, or 14 days postoperatively. Nonopioid regimens also resulted in significantly lower opioid consumption in the first 24 hours postoperatively (mean difference, -37.02 mg oral morphine equivalents, 95% confidence interval, -74.01 to -0.03). Transcutaneous electrical nerve stimulation (TENS), cryotherapy, and zolpidem were also found to effectively manage pain and reduce opioid use in a limited number of studies. CONCLUSIONS: A range of noninvasive pain management strategies exist to manage pain and reduce opioid use after arthroscopic procedures. The strongest evidence base supports the use of multimodal nonopioid oral analgesics, with some studies incorporating patient education components. Some evidence supports the efficacy of TENS, cryotherapy, and nonbenzodiazepine sleeping aids. Direction from governing bodies is an important next step to incorporate these adjuncts into routine clinical practice to manage pain and reduce the amount of opioids prescribed and consumed after arthroscopic surgery. LEVEL OF EVIDENCE: Level II, systematic review and meta-analysis of RCTs. See Instructions for Authors for a complete description of the levels of evidence.

What is the rate of successful closed reduction of dislocated dual mobility cups following complex revision hip arthroplasty?

PURPOSE: The aim of this study was to assess the difference in success rates of closed reduction in septic and aseptic revision total hip arthroplasty (THA) performed with a dual mobility (DM) implant. Our objective was to answer the following questions: (1) Is there a difference in success rates of closed reduction between septic and aseptic revision THA with a DM implant? (2) Is closed or open reduction more successful in preventing re-dislocation? METHODS: Between January 2009 and October 2021, 924 revisions were performed with a DM implant. All patients presenting to our institution with a dislocation following septic or aseptic revision THA using a cemented DM cup were included in this study. We analyzed 106 cases of dislocation in 74 patients. For all patients, we collected reason for revision, and classified index surgery as septic or aseptic. RESULTS: Overall, 106 dislocations occurred (106/924, 11.5%). Thirty-nine cases (52.7%) had a dislocation after a septic exchange THA, while in 35 patients (47.3%), a dislocation occurred after an aseptic rTHA. In 29 patients (39.2%), successful closed reduction under general anesthesia was feasible, while the majority of cases required open reduction. In 31 of these patients (67.4%), open reduction was combined with a revision arthroplasty. CONCLUSIONS: In case of DM cup dislocation, there is a low success rate of closed reduction. To prevent re-dislocation, total revision leads to a significantly reduced risk compared to open or closed reduction alone. Careful X-ray analysis for a halo sign showing intra-prosthetic DM cup dislocation is mandatory to avoid futile reduction attempts. LEVEL OF EVIDENCE: III.

Unexpected Positive Cultures in Patients Who Have a History of Septic Revision in the Same Joint.

BACKGROUND: The prevalence of unexpected positive cultures (UPC) in an aseptic revision surgery of the joint with a prior septic revision in the same joint remains unknown. The purpose of this study was to determine the prevalence of UPC in that specific group. As secondary outcomes, we explored risk factors for UPC. METHODS: This retrospective study includes patients who had an aseptic revision total hip/knee arthroplasty procedure with a prior septic revision in the same joint. Patients who had less than 3 microbiology samples, without joint aspiration or with aseptic revision surgery performed <3 weeks after a septic revision were excluded. The UPC was defined as a single positive culture in a revision that the surgeon had classified as aseptic according to the 2018 International Consensus Meeting. After excluding 47, a total of 92 patients were analyzed, who had a mean age of 70 years (range, 38 to 87). There were 66 (71.7%) hips and 26 (28.3%) knees. The mean time between revisions was 83 months (range, 31 to 212). RESULTS: We identified 11 (12%) UPC and in 3 cases there was a concordance of the bacteria compared to the previous septic surgery. There were no differences for UPC between hips/knees (P = .282), diabetes (P = .701), immunosuppression (P = .252), previous 1-stage or 2-stages (P = .316), causes for the aseptic revision (P = .429) and time after the septic revision (P = .773). CONCLUSION: The prevalence of UPC in this specific group was similar to those reported in the literature for aseptic revisions. More studies are needed to better interpret the results.

Periprosthetic joint infection in patients with multiple arthroplasties.

Despite numerous studies focusing on periprosthetic joint infections (PJIs), there are no robust data on the risk factors and timing of metachronous infections. Metachronous PJIs are PJIs that can arise in the same or other artificial joints after a period of time, in patients who have previously had PJI. Between January 2010 and December 2018, 661 patients with multiple joint prostheses in situ were treated for PJI at our institution. Of these, 73 patients (11%) developed a metachronous PJI (periprosthetic infection in patients who have previously had PJI in another joint, after a lag period) after a mean time interval of 49.5 months (SD 30.24; 7 to 82.9). To identify patient-related risk factors for a metachronous PJI, the following parameters were analyzed: sex; age; BMI; and pre-existing comorbidity. Metachronous infections were divided into three groups: Group 1, metachronous infections in ipsilateral joints; Group 2, metachronous infections of the contralateral lower limb; and Group 3, metachronous infections of the lower and upper limb. We identified a total of 73 metachronous PJIs: 32 PJIs in Group 1, 38 in Group 2, and one in Group 3. The rate of metachronous infection was 11% (73 out 661 cases) at a mean of four years following first infection. Diabetes mellitus incidence was found significantly more frequently in the metachronous infection group than in non-metachronous infection group. The rate of infection in Group 1 (21.1%) was significantly higher (p = 0.049) compared to Groups 2 (6.2%) and 3 (3%). The time interval of metachronous infection development was shorter in adjacent joint infections. Concordance between the bacterium of the first PJI and that of the metachronous PJI in Group 1 (21/34) was significantly higher than Group 2 (13/38; p = 0.001). The findings of this study suggest that metachronous PJI occurs in more than one in ten patients with an index PJI. Female patients, diabetic patients, and patients with a polymicrobial index PJI are at significantly higher risk for developing a metachronous PJI. Furthermore, metachronous PJIs are significantly more likely to occur in an adjacent joint (e.g. ipsilateral hip and knee) as opposed to a more remote site (i.e. contralateral or upper vs lower limb). Additionally, adjacent joint PJIs occur significantly earlier and are more likely to be caused by the same bacteria as the index PJI.

Common errors in the design of orthopaedic trials: Has anything changed?

INTRODUCTION: The adoption of evidence-based orthopaedics has shifted the focus from expert base opinions and anecdotal evidence to a focus on integrating the best available clinical research. This shift has led to an increased focus on randomized controlled trials (RCTs) within the field. Although RCTs are considered the highest level of evidence, methodologic errors can introduce bias and limit the validity of the results. Early trials were hampered by lack of blinding, inadequate sample sizes and other design flaws. The objective of this review was to examine the current literature to determine if the design and execution of RCTs has improved. DESIGN ERRORS: The awareness of the importance of sample size increased over time with substantially more trials reporting sample size calculations. However, many contemporary RCTs are still underpowered and fail to reach their calculated sample size. Given the challenges of surgically based RCTs, the majority of historical trials lacked blinding, increasing the risk of bias. There is evidence that there has been a concerted effort to increase the blinding in RCTs, particularly in outcome assessors. A more recent development in the design of surgical trials is the introduction of expertise-based trial designs in which patients are randomized to a surgeon with expertise in a particular intervention. These trials minimize the bias that can arise from differential expertise bias and have the potential to improve the validity and feasibility of RCTs. Finally, there has been an increased focus on the reporting of patient reported outcomes (PROs) in orthopaedic RCTs. Alongside this movement has been the development of minimal important differences (MIDs) to define the changes that are relevant and meaningful to patients. Both PROs and MIDs should be taken into consideration when calculating the sample size and study power in clinical trials. CONCLUSIONS: Although marked improvements have been made in the design and implementation of trials, there is still considerable room for improvement. Adequately blinded and powered studies evaluating clinically important outcomes and differences should be key considerations in trial design moving forward.

Registries: Big data, bigger problems?

Patient registries have grown in size and number along with general computing power and digitization of the healthcare world. In contrast to databases, registries are typically patient data systematically created and collected for the express purpose of answering health-related questions. Registries can be disease-, procedure-, pathology-, or product-based in nature. Registry-based studies typically fit into Level II or III in the hierarchy of evidence-based medicine. However, a recent advent in the use of registry data has been the development and execution of registry-based trials, such as the TASTE trial, which may elevate registry-based studies into the realm of Level I evidence. Some strengths of registries include the sheer volume of data, the inclusion of a diverse set of participants, and their ability to be linked to other registries and databases. Limitations of registries include variable quality of the collected data, and a lack of active follow-up (which may underestimate rates of adverse events). As with any study type, the intended design does not automatically lead to a study of a certain quality. While no specific tool exists for assessing the quality of a registry-based study, some important considerations include ensuring the registry is appropriate for the question being asked, whether the patient population is representative, the presence of an appropriate comparison group, and the validity and generalizability of the registry in question. The future of clinical registries remains to be seen, but the incorporation of big data and machine learning algorithms will certainly play an important role.