Statistics in Brief: An Introduction to the Use of Propensity Scores

Conversion of hip resurfacing to total hip arthroplasty: is the outcome closer to primary or revision total hip arthroplasty?

BACKGROUND

Along with the advent of newer bearings, hip resurfacing (HR) is gaining renewed interest as a bone sparing alternative to conventional total hip arthroplasty (THA) in young patients. However, the outcome of conversion of failed HR to THA (HRc) remains sparsely described. This study aimed to compare the outcomes and complication rates of HRc to those of primary (pTHA) and revision THA (rTHA) to find out to which group HRc is most comparable.

HYPOTHESIS

The study hypothesis was that the outcomes and complications rates of HRc were closer to those of pTHA than rTHA.

MATERIALS AND METHODS

Between 2001 and 2011, a continuous series of 207 HR were prospectively included in our institutional registry and retrospectively analyzed. Out of them, 17 HR (8%) were converted to THA. Propensity scores were used to match patients in the HRc group to the pTHA and the rTHA groups using a greedy 1:3 matching procedure (51 pTHA and 51 rTHA). Clinical and radiographic outcomes, perioperative data and complications were analyzed and compared between the three groups.

RESULTS

No significant difference between HRc and pTHA was observed in terms of clinical and functional outcomes, duration of surgery, acetabular component diameter and length of hospital stay (p = 0.13 to 0.94). Perioperative blood loss was significantly lower for pTHA than for HRc (p = 0.01). HRc demonstrated significantly higher HHS and HOOS scores than for rTHA at one year (p = 0.03 and p < 0.01, respectively). Duration of surgery was significantly lower in HRc compared to rTHA (p = 0.02) while length of hospital stay was similar (p = 0.84). Complication rate was significantly higher in the rTHA group, compared to HRc and pTHA groups (37.3 vs. 29.4 vs. 11.8%, p = 0.01).

CONCLUSION

This study demonstrated that the clinical and functional outcomes of HRc were closer to those of pTHA than those of rTHA, though complication rate was higher than for pTHA.

LEVEL OF EVIDENCE

III; Retrospective comparative study.

The Safety of Spinal Surgery in Patients over 80 Years of Age: Propensity Score Matching Study

STUDY DESIGN

Retrospective cohort study.

OBJECTIVES

Using propensity match score to remove those confounding bias and focuses on age factor to compare clinical outcomes and perioperative complications following spinal surgery in cohort of Korean octogenarians treated at a single tertiary hospital.

METHODS

We classified patients of 80s as the octogenarian group (group O), those 65 and older, and under 80 as the elderly group (group E). We strategically employed the Propensity Score Matching (PSM) analysis as a method to counteract potential confounding variables. 1: 1 nearest-neighbor PSM for fusion level, estimated blood loss (EBL), transfusion, body mass index (BMI), American society of anesthesiologists (ASA) score, Charlson Comorbidity Index (CCI) surgical method and operation time was performed. After PSM, 98 patients are categorized each group evenly (group O, n = 49 vs group E, n = 49). Demographics, clinical, radiologic and postoperative complications were analyzed.

RESULTS

The clinical outcomes showed no significant differences in the VAS and ODI preoperatively or postoperatively. And most of hospitalization related factors shows no differences between 2 groups. However, follow-up period was longer in group E (1053.37 ± 684.14 days) than group O (640.29 ± 496.68, P = 0.001) and group O has higher incidences of medical complication (38.77% vs 16.32%, P = 0.013), especially in delirium (34.69% vs 6.12%, P = 0.001) than group E.

CONCLUSIONS

With the preparation for the prevention and treatment of postoperative delirium, age itself should not be a reason to hesitate in performing the spinal surgery.

Health outcomes following provision of Home Medicines Reviews for older people receiving aged care services at home

BACKGROUND

The impact of Home Medicines Reviews (HMRs) on long-term health outcomes among individuals receiving long-term in-home aged care services is unknown.

OBJECTIVES

To examine associations between HMR provision and hospitalization, long-term care facility (LTCF) entry and mortality among older people receiving long-term in-home aged care services.

METHODS

This retrospective cohort study included individuals aged 65-105 years from three Australian states who accessed in-home aged care services between 2013 and 2017. Using propensity score matching, HMR recipients (n = 1530) were matched to individuals who did not receive an HMR (n = 1530). Associations between HMR provision and outcomes were estimated using multivariable regression models.

RESULTS

Over a median of 414 days (interquartile range 217-650) of follow-up, HMR provision was not associated with hospitalizations for unplanned events (subdistribution hazard ratio (sHR) 1.04, 95%CI 0.96-1.14), falls-related hospitalizations (sHR 0.97, 95%CI 0.83-1.13), LTCF entry (sHR 0.97, 95%CI 0.83-1.13), or all-cause mortality (adjusted HR 0.86, 95%CI 0.72-1.01).

CONCLUSIONS

In a cohort of older people receiving long-term in-home aged care services, no differences in unplanned hospitalizations, falls, LTCF entry or mortality were observed those with HMRs compared to those that did not receive an HMR.

Does previous sickness absence affect work participation after vocational labour market training? A difference-in-differences propensity score matching approach

BACKGROUND

Reduced work ability is relatively common among job seekers and it can hinder future labour market attachment. A commonly used measure to increase employability is the use of active labour market programmes. While vocational labour market training (LMT) has been shown to be an effective way to increase work participation among job seekers, there is still uncertainty about how LMT works in different population groups, for example, among persons with a work disability history.

METHODS

We used nationally representative Finnish register data on 16 062 LMT participants in 2008-2015 aged 25-59 with a history of sickness absence (SA) and propensity score matched participants without such history. For matching, we used information on sociodemographic and work-related factors. We used difference-in-differences analysis to investigate the differential changes in work participation before and after LMT between those with and those without SA history.

RESULTS

Having a history of SA was associated with a lower gain in work participation after LMT, but the magnitude varied by sex, employment history and follow-up time. In women, having a history of SA contributed to 3.9-6.2 percentage points smaller increase in work participation 1-3 years after LMT, depending on the employment history. In men, the corresponding numbers were 2.0-4.3 percentage points. The results were more pronounced if the SA was due to mental disorders.

CONCLUSIONS

The results indicate that work disability, especially due to mental disorders, can hamper work participation after LMT and should be considered when planning employment-enhancing measures for job seekers.

Postoperative Hemodynamics of Total Knee Arthroplasty Unaffected by Cementless Approach under Contemporary Patient Blood Management Protocol: A Propensity Score-Matched Study

(1) Background: A cementless total knee arthroplasty (TKA) is a recent and an increasingly popular innovation that enhances porous fixation surfaces. However, the lack of cemented sealing of an exposed resected bone has raised concerns about the potential for greater blood loss. The goals of this study were to determine if a cementless approach impacts post-TKA hemodynamics and to identify risk factors for blood loss in instances of cementless (vs. cemented) TKAs under a contemporary patient blood management (PBM) protocol. (2) Methods: We recruited 153 consecutive patients undergoing unilateral TKAs between 2019 and 2023. All enrollees received cementless or cemented prostheses of the same design (cementless, 87; cemented, 66). After propensity score matching for demographics, there were 46 patients in each group. We then compared blood loss metrics (total [TBL] and estimated [EBL]), drainage volumes, hemoglobin (Hb) levels, and transfusion rates by group. (3) Results: Post-TKA hemodynamics (i.e., TBL, EBL, drainage, Hb level, and transfusion rate) of cementless (n = 46) and cemented (n = 46) TKA groups did not differ significantly. In addition, the proportions of patients with Hb drops > 3.0 g/dL were similar for the two groups. A logistic regression analysis revealed that only preoperative Hb and EBL during the early postoperative period were predictive of a substantial fall in Hb levels. The fixation method was not associated with Hb decline > 3.0 g/dL by postoperative Day 3. (4) Conclusion: The cementless TKA has no impact on customary post-TKA hemodynamics and is not associated with greater TKA-related blood loss when implementing a contemporary PBM protocol.

The effect of smoking on latent hazard classes of metabolic syndrome using latent class causal analysis method in the Iranian population

BACKGROUND

The prevalence of metabolic syndrome is increasing worldwide. Clinical guidelines consider metabolic syndrome as an all or none medical condition. One proposed method for classifying metabolic syndrome is latent class analysis (LCA). One approach to causal inference in LCA is using propensity score (PS) methods. The aim of this study was to investigate the causal effect of smoking on latent hazard classes of metabolic syndrome using the method of latent class causal analysis.

METHODS

In this study, we used data from the Tehran Lipid and Glucose Cohort Study (TLGS). 4857 participants aged over 20 years with complete information on exposure (smoking) and confounders in the third phase (2005-2008) were included. Metabolic syndrome was evaluated as outcome and latent variable in LCA in the data of the fifth phase (2014-2015). The step-by-step procedure for conducting causal inference in LCA included: (1) PS estimation and evaluation of overlap, (2) calculation of inverse probability-of-treatment weighting (IPTW), (3) PS matching, (4) evaluating balance of confounding variables between exposure groups, and (5) conducting LCA using the weighted or matched data set.

RESULTS

Based on the results of IPTW which compared the low, medium and high risk classes of metabolic syndrome (compared to a class without metabolic syndrome), no association was found between smoking and the metabolic syndrome latent classes. PS matching which compared low and moderate risk classes compared to class without metabolic syndrome, showed that smoking increases the probability of being in the low-risk class of metabolic syndrome (OR: 2.19; 95% CI: 1.32, 3.63). In the unadjusted analysis, smoking increased the chances of being in the low-risk (OR: 1.45; 95% CI: 1.01, 2.08) and moderate-risk (OR: 1.68; 95% CI: 1.18, 2.40) classes of metabolic syndrome compared to the class without metabolic syndrome.

CONCLUSIONS

Based on the results, the causal effect of smoking on latent hazard classes of metabolic syndrome can be different based on the type of PS method. In adjusted analysis, no relationship was observed between smoking and moderate-risk and high-risk classes of metabolic syndrome.

Understanding the Clinical Implications of Individual Patient Characteristics and Treatment Choice on the Risk of Exacerbation in Asthma Patients with Moderate-Severe Symptoms

INTRODUCTION

The assessment of future risk has become an important feature in the management of patients with asthma. However, the contribution of patient-specific characteristics and treatment choices to the risk of exacerbation is poorly understood. Here we evaluated the effect of interindividual baseline differences on the risk of exacerbation and treatment performance in patients receiving regular maintenance doses of inhaled corticosteroids (ICS) or ICS/long-acting beta-agonists (LABA) combination therapy.

METHODS

Exacerbations and changes to asthma symptoms 5-item Asthma Control Questionnaire (ACQ-5) were simulated over a 12-month period using a time-to-event and a longitudinal model developed from phase III/IV studies in patients with moderate-severe asthma (N = 16,282). Simulations were implemented to explore treatment performance across different scenarios, including randomised designs and real-world settings. Treatment options included regular dosing with ICS monotherapy [fluticasone propionate (FP)] and combination therapy [fluticasone propionate/salmeterol (FP/SAL) or budesonide/formoterol (BUD/FOR)]. Exacerbation rate was analysed using the log-rank test. The cumulative incidence of events was summarised stratified by treatment.

RESULTS

Being a woman, smoker, having higher baseline ACQ-5 and body mass index (BMI) and lower forced expiratory volume in the first second (FEV1) are associated with increased exacerbation risk (p < 0.01). This risk is bigger in winter because of the seasonal variation effect. Across the different scenarios, the use of FP/SAL resulted in a 10% lower annual incidence of exacerbations relative to FP or regular dosing BUD/FOR, independently of baseline characteristics. Similar differences in the annual incidence of exacerbations were also observed between treatments in obese patients (BMI ≥ 25-35 kg/m2) (p < 0.01) and in patients who do not achieve symptom control on FP monotherapy.

CONCLUSIONS

Individual baseline characteristics and treatment choices affect future risk. Achieving comparable levels of symptom control whilst on treatment does not imply comparable risk reduction, as shown by the lower exacerbation rates in FP/SAL vs. BUD/FOR-treated patients. These factors should be considered as a basis for personalised clinical management of patients with moderate-severe asthma.

What are the factors of parental incarceration that may increase risk of poor emotional and mental health in children of prisoners?

PURPOSE

Globally millions of children have a parent who is imprisoned. Research suggests that this has an adverse impact on the child and imprisonment of a parent is considered to be an adverse childhood experience (ACE). Parental incarceration will not only affect the child but the entire household and may result in further ACEs such as household dysfunction and parental separation making this group of children particularly vulnerable. This scoping review aims to adopt an international perspective to comprehensively examine the extent range and nature of literature both published and grey relating to parental incarceration and the potential impact on children's emotional and mental health.

DESIGN/METHODOLOGY/APPROACH

In this scoping review, the five stages identified by Arksey and O'Malley (2005) were used including identifying the research question, identifying relevant studies, study selection, charting data, collating, summarising and reporting results. In addition, the included studies were appraised for quality using methodology-specific tools. A critical narrative synthesis was adopted to present findings and discussion.

FINDINGS

Nine studies met the inclusion criteria. Of the included studies, eight were retrieved from peer-reviewed journals and one from grey literature searching. Five categories with subcategories were identified affecting children's mental health: 1) Relationships: parent and incarcerated child relationship; facilitators and barriers to maintaining contact; 2) Family structure; maternal or paternal incarceration; living arrangements during parental incarceration; 3) Children's emotions: emotional recognition and regulation; resilience; 4) Prison stigma: social stigma; shame and secrecy; 5) Structural disadvantages: poverty; race/ethnicity.

ORIGINALITY/VALUE

This scoping review has highlighted how the imprisonment of a parent negatively affects their children's emotional and mental health. Factors negatively impacting children's emotional and mental health are interrelated and complex. Further research is required, including differences between paternal and maternal incarceration; impact of gender and age of child; poverty as an ACE and prison exacerbating this; and effects of ethnicity and race. An important policy direction is in developing an effective way of capturing the parental status of a prisoner to ensure that the child and family receive needed support.

An analysis of the usefulness for using skin adhesive without closed-suction drainage in primary total hip arthroplasty: A retrospective propensity score matched study

The closed suction surgical drainage system (CSSD) is routinely used after total hip arthroplasty (THA) by orthopedic surgeons in many institutions. However, it has not been shown to decrease the rate of wound infection significantly and may even increase blood loss. This study aimed to evaluate the usefulness of using skin adhesive without CSSD in uncomplicated THA. From July 2015 to September 2017, 200 patients undergoing unilateral THA were enrolled and divided into 2 groups, either receive CSSD (134 patients) or not receive CSSD (66 patients). Then, the propensity matched was performed. Calculated total blood loss, changes in hemoglobin (Hgb) level, transfusions were evaluated. In addition, data on the length of hospital stay, operation time, closure time, time to using crutches following THA were collected. Finally, Harris hip score (HHS), total estimated cost, and complications were assessed. The non-CSSD group had comparatively less blood loss (508.5 ± 280.3 mL compared with 742.1 ± 330.3 mL, P < .001), fewer transfusions (0.03 units compared with 0.3 units, P = .02), less transfusion rate (1.9% compared with 17.3 %, P = .02), lower change of Hgb from immediate postoperative period to 3 days later(1.6 ± 1.0 g/dL compared with 2.0 ± 0.8 g/dL, P = .03), than the CSSD group. There was a longer duration of hospital stay in the CSSD groups (7.2 days compared with 7.8 days, P = .03) The mean total cost in the non-CSSD group was $162.1, which was less than that of the CSSD group, which spent $288.5 on average (P < .001). there was 1 allergic reaction in the non-CSSD group (P = .32). The use of skin adhesive without CSSD could help decrease blood loss, the need for transfusion, and the length of hospital stay, and seems to more cost-effectiveness than using CSSD. It may also provide superior results and allow the patient to recover faster. Using this type of skin adhesive without CSSD is an efficient wound closure method for patients undergoing uncomplicated THA. However, care must be taken for allergic reactions, especially for patients with known or suspected allergies to cyanoacrylate or formaldehyde.

Impact of Hepatitis B virus infection on postoperative complications and length of stay in elderly patients with hip fracture: A retrospective cohort study

BACKGROUND

Osteoporosis and subsequent fractures are common in the chronic hepatitis B (CHB) population, especially in the elderly. This study investigated the effects of hepatitis B virus (HBV) infection on postoperative outcomes following hip fracture surgery.

METHODS

The study identified elderly patients who underwent hip fracture surgery at three academic tertiary care centres between January 2014 and December 2020. Propensity score matching was performed to compare the outcomes of 1,046 patients with HBV infection to 1,046 controls.

RESULTS

The seroprevalence of HBV among elderly patients undergoing hip surgery was 4.94%. The HBV cohort had significantly higher rates of medical complications (28.1 vs. 22.7%, p = 0.005), surgical complications (14.0 vs. 9.7%, p = 0.003), and unplanned readmissions (18.9 vs. 14.5%, p = 0.03) within 90 days of surgery. Patients with HBV infection were more likely to have increased length of stay (6.2 vs. 5.9 days, p = 0.009) and in-hospital charges (¥52,231 vs. ¥49,832, p < 0.00001). Multivariate logistic regression suggested that liver fibrosis and thrombocytopenia were independent risk factors for major complications and extended LOS.

CONCLUSION

Patients with HBV infection were at greater risk of adverse postoperative outcomes. We should pay more attention to the considerable burden of perioperative management of CHB patients. Due to the high proportion of undiagnosed patients in the Chinese elderly population, universal HBV screening should be considered preoperatively.

Safety and effectiveness of ataluren in patients with nonsense mutation DMD in the STRIDE Registry compared with the CINRG Duchenne Natural History Study (2015-2022): 2022 interim analysis

OBJECTIVE

Strategic Targeting of Registries and International Database of Excellence (STRIDE) is an ongoing, international, multicenter registry of real-world ataluren use in individuals with nonsense mutation Duchenne muscular dystrophy (nmDMD) in clinical practice. This updated interim report (data cut-off: January 31, 2022), describes STRIDE patient characteristics and ataluren safety data, as well as the effectiveness of ataluren plus standard of care (SoC) in STRIDE versus SoC alone in the Cooperative International Neuromuscular Research Group (CINRG) Duchenne Natural History Study (DNHS).

METHODS

Patients are followed up from enrollment for at least 5 years or until study withdrawal. Propensity score matching was performed to identify STRIDE and CINRG DNHS patients who were comparable in established predictors of disease progression.

RESULTS

As of January 31, 2022, 307 patients were enrolled from 14 countries. Mean (standard deviation [SD]) ages at first symptoms and at genetic diagnosis were 2.9 (1.7) years and 4.5 (3.7) years, respectively. Mean (SD) duration of ataluren exposure was 1671 (56.8) days. Ataluren had a favorable safety profile; most treatment-emergent adverse events were mild or moderate and unrelated to ataluren. Kaplan-Meier analyses demonstrated that ataluren plus SoC significantly delayed age at loss of ambulation by 4 years (p < 0.0001) and age at decline to %-predicted forced vital capacity of < 60% and < 50% by 1.8 years (p = 0.0021) and 2.3 years (p = 0.0207), respectively, compared with SoC alone.

CONCLUSION

Long-term, real-world treatment with ataluren plus SoC delays several disease progression milestones in individuals with nmDMD. NCT02369731; registration date: February 24, 2015.

Osteoclast and Sclerostin Expression in Osteocytes in the Femoral Head with Risedronate Therapy in Patients with Hip Fractures: A Retrospective Comparative Study

Background and Objectives: The majority of research on the effects of osteoporosis drugs has measured the bone mineral density (BMD) of the spine and femur through dual-energy X-ray absorptiometry (DEXA) and compared and analyzed the effects of the drugs through changes in the BMD values. This study aims to compare osteoclast and sclerostin expression in osteocytes after risedronate therapy by obtaining femoral heads from patients with hip fractures. Materials and Methods: We obtained the femoral heads of 10 female patients (age: ≥65 years) who received risedronate therapy for at least 1 year through hip arthroplasty during 2019−2021 (risedronate group). Meanwhile, 10 patients who had never received osteoporosis treatment were selected as controls using propensity scores with age, body mass index, and bone density as covariates (control group). While the osteoclast count was evaluated using tartrate-resistant acid phosphatase (TRAP) staining, the sclerostin expression in osteocytes was assessed using immunohistochemistry. Moreover, Western blotting and polymerase chain reaction (PCR) were performed for receptor activation of nuclear factor kappa-Β ligand (RANKL), RANK, osteoprotegerin (OPG), sclerostin, and bone morphogenetic protein-2 (BMP2). Results: TRAP staining revealed significantly more TRAP-positive cells in the control group (131.75 ± 27.16/mm2) than in the risedronate group (28.00 ± 8.12/mm2). Moreover, sclerostin-positive osteocytes were expressed more in the control group (364.12 ± 28.12/mm2) than in the risedronate group (106.93 ± 12.85/mm2). Western blotting revealed that the expressions of RANKL, RANK, sclerostin, and BMP2 were higher in the control group than in the risedronate group (p < 0.05). Furthermore, RANK, sclerostin, and OPG protein levels were higher in the control group than in the risedronate group. Conclusions: In this study, the risedronate group demonstrated lower osteoclast activity and sclerostin expression in osteocytes in the femoral head than the control group.

No Difference in Quality-Of-Life Outcomes in the First 7 Years Following Primary Total Knee Arthroplasty Performed Using Computer Navigation Versus Conventional Referencing: A Propensity Score-Matched Analysis

BACKGROUND

Computer navigation techniques can potentially improve both the accuracy and precision of prosthesis implantation in total knee arthroplasty (TKA) but its impact on quality-of-life outcomes following surgery remains unestablished.

METHODS

An institutional arthroplasty registry was queried to identify patients with TKA performed between January 1, 2007 and December 31, 2019. Propensity score matching based on demographical, medical, and surgical variables was used to match computer-navigated to conventionally referenced cases. The primary outcomes were Veterans RAND 12 Item Health Survey scores (VR-12 PCS and MCS), Short Form 6 Dimension utility values (SF-6D), and quality-adjusted life years (QALYs) in the first 7 years following surgery.

RESULTS

A total of 629 computer-navigated TKAs were successfully matched to 1,351 conventional TKAs. The VR-12 PCS improved by a mean of 12.75 and 11.94 points in computer-navigated and conventional cases at 12-month follow-up (P = .25) and the VR-12 MCS by 6.91 and 5.93 points (P = .25), respectively. The mean VR-12 PCS improvement at 7-year follow-up (34.4% of the original matched cohort) for navigated and conventional cases was 13.00 and 12.92 points (P = .96) and for the VR-12 MCS was 4.83 and 6.30 points (P = .47), respectively. The mean improvement in the SF-6D utility score was 0.164 and 0.149 points at 12 months (P = .11) and at 7 years was 0.115 and 0.123 points (P = .69), respectively. Computer-navigated cases accumulated 0.809 QALYs in the first 7 years, compared to 0.875 QALYs in conventionally referenced cases (P = .65). There were no differences in these outcomes among a subgroup analysis of obese patients (body mass index ≥ 30 kg/m²).

CONCLUSION

The use of computer navigation did not provide an incremental benefit to quality-of-life outcomes at a mean of 2.9 years following primary TKA performed for osteoarthritis when compared to conventional referencing techniques.

Home Health Care in Medicare-Aged Patients is Associated With Increased Early Emergency Visits, Readmissions, and Costs Following Total Knee Arthroplasty

BACKGROUND

Home health services are utilized in order to provide at-home care following total knee arthroplasty (TKA). The purpose of this study is to determine whether patients receiving home health services post-operatively had lower rates of complications, emergency room visits, and readmissions as well as to determine if home health provided value by reducing total episode-of-care costs.

METHODS

The PearlDiver database was retrospectively reviewed to identify all primary TKA patients over 65 years old from 2010 to 2018. Patients who received home health services were matched using a propensity score algorithm to a set of similar patients who were discharged home under self-care. We compared complication rates, emergency room visits, readmissions, and 90-day episode-of-care claims costs between the groups. Multivariate regression analysis was performed to determine the independent effect of home health services on emergency department (ED) visits and hospital readmissions.

RESULTS

Of the 185,444 TKA patients discharged home, 15,849 (8.5%) received home health services. Patients who received home health services had higher rates of ED visits at 2 weeks (3.3% vs 2.8%, P = .014) and 3 months (7.1% vs 6.5%, P = .038) as well as increased readmissions at 2 weeks (0.9% vs 0.7%, P = .028); complication rates were similar between groups (11.4% vs 10.9%, P = .159). Episode-of-care costs for home health patients were higher than those discharged under self-care ($24,266 vs $22,539, P < .001).

CONCLUSION

Home health services do not appear to provide value as they are associated with significantly increased costs and do not lower the rates of complications, ED visits, or readmissions following TKA.

Intra-Articular Corticosteroid or Hyaluronic Acid Injections Are Not Associated with Periprosthetic Joint Infection Risk following Total Knee Arthroplasty

This study evaluated whether the preoperative use and timing of the use of hyaluronic acid (HA) and/or corticosteroid (CS) injections were associated with an increased risk of periprosthetic joint infections (PJIs) following primary total knee arthroplasty (TKA). We tested the hypothesis that preoperative injection of HA or CS within 3 months prior to primary TKA was associated with an increased risk of PJI by specifically evaluating the association between PJI risk and (1) injection type; (2) timing; (3) patient demographic factors; and (4) surgery-related factors, such as surgeon injection volume, knee arthroscopy (pre- and postoperative), and hospital length of stay. The 5% Medicare part B claims database was queried for patients who received CS and/or HA injections. Cox proportional hazards regressions evaluated the risk of PJIs after TKA, adjusting for patient and clinical factors, as well as propensity scores. The unadjusted incidence of PJI at 2-year post-TKA was 0.75% for the CS group, 0.89% for the HA group, 0.96% for both CS and HA group, and 0.75% for those who did not use HA or CS in the 12 months before TKA. For patients who used HA and/or CS within 3 months prior to TKA, the unadjusted incidence of PJI at 2-year post-TKA was 0.75% for the CS group, 1.07% for the HA group, and 1.00% for both CS and HA group, compared with 0.77% for those who did not use HA or CS. The number of injections performed per year was inconsistently associated with PJI risk. Overall, we found that intra-articular injections given within the 4-month period prior to TKA were not associated with elevated PJI risk (evaluated at 1, 3, 12, and 24 months after the index TKA) within the elderly Medicare patient population.

Minimum 5-Year Outcomes After Primary Segmental Labral Reconstruction for Irreparable Labral Tears in the Hip With Hamstring Grafts: With a Subanalysis Comparing Autograft Versus Allograft

BACKGROUND

Comparable short-term outcomes have been obtained using hamstring allografts versus autografts after primary segmental labral reconstruction (SLR). Midterm results have not yet been determined.

PURPOSE

(1) To evaluate minimum 5-year patient-reported outcome (PRO) scores in patients who underwent primary SLR with hamstring grafts in the setting of femoroacetabular impingement syndrome (FAIS) and irreparable labral tears and (2) to compare the outcomes of hamstring autografts versus allografts in a subanalysis using propensity-matched groups.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Prospectively collected data were retrospectively reviewed for patients who underwent primary hip arthroscopy between September 2010 and November 2015. Patients were included if they underwent SLR using hamstring autografts or allografts and had preoperative and minimum 5-year PROs. The exclusion criteria were previous ipsilateral hip surgery or conditions, dysplasia, or Tönnis grade >1. Patients with autograft SLR were propensity matched 1 to 1 based on age, sex, and body mass index (BMI) to patients who underwent SLR using hamstring allografts. The minimal clinically important difference (MCID) and the Patient Acceptable Symptom State (PASS) were calculated.

RESULTS

Overall, 48 patients (N = hips 48) were eligible to be included in this study, and 41 patients (n = 41 hips [85.4%]) had a minimum 5-year follow-up reporting significant improvements in all PROs. Within the entire cohort, 9.8% required a secondary arthroscopy, with a mean time of 19 ± 1.8 months, and survivorship was 82.9%. Of the 41 included patients, 15 underwent an SLR with a hamstring autograft and were matched to 15 patients with labral reconstruction using a hamstring allograft. Groups were similar for sex (P > .999), age (P = .775), and BMI (P = .486). The mean follow-up times were 80.8 ± 25.5 and 66.1 ± 8.3 months (P = .223) for the autograft and allograft groups, respectively. Baseline PROs, preoperative radiographic measurements, surgical findings, and intraoperative procedures were similar. The groups achieved significant and comparable improvements for all PROs (P < .0001), satisfaction (P = .187), and the rate of achieving the MCID and the PASS. However, a tendency for higher postoperative PROs favoring allograft reconstruction was found.

CONCLUSION

At a minimum 5-year follow-up, patients who underwent primary arthroscopic SLR in the context of FAIS and irreparable labra, with either autograft or allograft hamstring tendons, reported significant improvements and comparable postoperative scores for all PROs, patient satisfaction, MCID, and PASS.

Effects of Spinal Anesthesia in Geriatric Hip Fracture: A Propensity-Matched Study

OBJECTIVES

To identify whether anesthesia type is associated with surgical outcomes in geriatric patients undergoing operative treatment for a hip fracture.

DESIGN

Retrospective database review of prospectively collected data.

PATIENTS

Patients included in the American College of Surgeons National Surgical Quality Improvement Program database. All included patients were 65-89 years of age and had a hip fracture treated with internal fixation, arthroplasty, or intramedullary device. Patients were excluded for open, pathologic, stress-related, or periprosthetic hip fractures.

INTERVENTION

Use of spinal anesthesia (SA) or general anesthesia (GA).

MAIN OUTCOME MEASUREMENTS

Complications, mortality, and discharge destination.

RESULTS

A total of 23,649 cases met inclusion and exclusion criteria and were successfully matched using propensity score matching: 15,766 GA and 7883 SA. The odds of sustaining a complication were 21% lower in the SA group compared with those in the GA group (odds ratio SA/GA 0.791; 95% confidence interval, 0.747-0.838). The 30-day mortality rate was not correlated with SA or GA choice. Patients who underwent SA were significantly more likely to be discharged to home (odds ratio SA/GA 1.65; 95% confidence interval, 1.531-1.773).

CONCLUSIONS

No mortality difference exists between patients undergoing SA and those undergoing GA for hip fracture surgery. For patients undergoing hip fracture surgery with SA, there is lower 30-day complication profile and higher discharge to home rate compared with those undergoing GA. Both anesthesia modalities may be acceptable.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Workers' Compensation Patients Improved After Hip Arthroscopy for Labral Tears: A 5-Year Outcome Propensity Score-Matched Study

BACKGROUND

The workers' compensation (WC) status has been associated with inferior outcomes in orthopaedic procedures and is usually excluded from clinical outcome studies. Therefore, comparative studies based on WC status are scarce.

PURPOSE

(1) To determine outcomes of patients with WC claims treated with hip arthroscopy for labral tears at a minimum 5-year follow-up and (2) to compare these findings with a propensity score-matched control group without WC claims.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Patients were propensity score matched to a control group without WC claims. Data were prospectively collected for all patients undergoing hip arthroscopy. Patients were included if they received primary hip arthroscopy for labral tears in the setting of femoroacetabular impingement, had a WC claim, and had preoperative and minimum 5-year follow-up patient-reported outcomes ([PROs]; modified Harris Hip Score [mHHS], Non-Arthritic Hip Score [NAHS], Hip Outcome Score-Sports Specific Subscale [HOS-SSS], and visual analog scale [VAS] for pain). Clinical outcomes were measured using the Patient Acceptable Symptom State (PASS), minimal clinically important difference (MCID), and maximum outcome improvement satisfaction threshold (MOI).

RESULTS

A total of 111 from 132 (84.1%) eligible WC patients met the inclusion criteria with an average follow-up time of 80.3 ± 37.3 months. WC cases demonstrated significant improvement from preoperatively to a minimum 5-year follow-up for mHHS, NAHS, HOS-SSS, and VAS for pain (P < .05). WC patients returned to work at a 66% rate, with an average clearance time of 4.7 months to light duty and 9.5 months to heavy duty. When compared with the control group, the WC group demonstrated lower pre- and postoperative PROs (P < .05); however, WC cases had a greater magnitude of improvement (ΔmHHS [P = .0012], ΔNAHS [P < .001], and ΔHOS-SSS [P = .012]). Rates of achieving MCID and MOI were similar in both groups (P > .05). The WC group went on to receive a future arthroscopy in 19 cases (17.1%), while 10 cases (4.5%) in the control group required revision arthroscopy (P < .001). Patients in both the WC and the control groups converted to total hip arthroplasty at similar rates (13.3% and 15.4%, respectively; P > .05).

CONCLUSION

Patients with WC claims treated with hip arthroscopic surgery showed significant improvement and high rates of returning to work at a minimum 5-year follow-up. Although having lower scores in PROs and achieving PASS rates, no differences were found in MCID and MOI rates. Furthermore, WC patients had a greater magnitude of improvement from preoperatively to a minimum 5-year follow-up after hip arthroscopy. Therefore, even though more studies are needed to determine the causes of inconsistent outcomes in the WC population, hip arthroscopy can effectively treat labral tears in the setting of femoroacetabular impingement, regardless of the WC status.

Ambulatory Single-level Posterior Cervical Foraminotomy for Cervical Radiculopathy: A Propensity-matched Analysis of Complication Rates

STUDY DESIGN

Retrospective cohort comparison study.

OBJECTIVE

The aim was to compare perioperative complications and 30-day readmission between ambulatory and inpatient posterior cervical foraminotomy (PCF) in the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) database.

SUMMARY OF BACKGROUND DATA

Single-level PCF for cervical radiculopathy is increasingly being performed as an ambulatory procedure. Despite this increase, there is a lack of published literature documenting the safety of ambulatory PCF.

MATERIALS AND METHODS

Patients who underwent PCF (through laminotomy or laminectomy) were identified in the 2005-2018 NSQIP database. Ambulatory procedures were defined as cases that had hospital length of stay=0 days. Inpatient procedures were defined as cases that had length of stay=1-4 days. Patient characteristics, comorbidities, and procedural variables (laminotomy or laminectomy performed) were compared between the 2 cohorts. Propensity score matched comparisons were then performed for postoperative complications and 30-day readmissions between the 2 groups.

RESULTS

In total, 795 ambulatory and 1789 inpatient single-level PCF cases were identified. After matching, there were 795 ambulatory and 795 inpatient cases. Statistical analysis after propensity score matching revealed no significant difference in individual complications including 30-day readmission, thromboembolic events, wound complications, and reoperation, or aggregated complications between ambulatory versus matched inpatient procedures. Overall 30-day readmissions after ambulatory single-level PCF were noted for 2.46% of the study population, and the most common reasons were surgical site infections (46%) and pain control (15%).

CONCLUSIONS

The perioperative outcomes assessed in this study support the conclusion that single-level PCF for cervical radiculopathy can be performed for correctly selected patients in the ambulatory setting without increased rates of 30-day perioperative complications or readmissions compared with inpatient procedures.

LEVEL OF EVIDENCE

Level III.

Iterative Cytoreduction and Hyperthermic Intraperitoneal Chemotherapy for Recurrent Mucinous Adenocarcinoma of the Appendix

BACKGROUND

Recurrence after cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) for appendiceal tumors (AT) with mucinous carcinomatosis peritonei (MCP) is common. The evidence favoring iterative procedures (iCRS/HIPEC) is limited, and its benefit is not clear for all patients.

METHODS

Retrospective (1998-2020) cohorts of AT patients with MCP recurrence after the first CRS/HIPEC were analyzed. Outcomes were compared within tumor grades between iCRS/HIPEC patients and matched control patients without iCRS/HIPEC using propensity score matching (1:1). Post-recurrence survival (PRS) was measured from the date of recurrence after the first CRS/HIPEC to death or last contact.

RESULTS

Overall, 55 iCRS/HIPEC patients were identified: 36 low-grade (LGMCP) patients, 13 high-grade (HGMCP) patients, and 6 HGMCP patients with signet-ring features (HGMCP-S). Nine patients had a third CRS/HIPEC. The median peritoneal cancer index (PCI) scores were 33, 19 and 10, with CC-0/1 achieved for 94.4%, 78.2% and 88.9% of the patients after the first, second, and third CRS/HIPEC, respectively. No 90-day postoperative mortality occurred. The median progression-free survival from the first CRS/HIPEC was 19.7 months for the iCRS/HIPEC patients versus 14.2 months for the matched control patients (p = 0.43). The median PRS was 80.2 months for iCRS/HIPEC versus 36.2 for the control patients (p < 0.001). For the iCRS/HIPEC versus the matched control patients, the median PRS by tumor grade was 174.1 versus 51.9 (p < 0.001) for the LGMCP, 42.0 versus 12.4 (p = 0.02) for the HGMCP, and 15.4 versus 8.1 months (p = 0.61) for the HGMCP-S patients, respectively.

CONCLUSIONS

Selected low- and high-grade appendiceal cancer patients with MCP recurrence able to undergo iterative CRS/HIPEC procedures showed favorable outcomes and such patients should be considered for surgery when feasible. This survival benefit with iCRS/HIPEC is not evidenced in recurrent MCP with signet ring cell morphology.

Comparative study of total hip arthroplasties with dual mobility cups versus hemiarthroplasties in management of femoral neck fractures: Survival and dislocation rate at 5 years of follow-up?

BACKGROUND

Instability after hip arthroplasty, whether it is a total (THA) or intermediate (HA), poses a major risk, however arthroplasty is the standard treatment for displaced intracapsular fractures of the femoral neck of the elderly. Three types of arthroplasties can be proposed: total prostheses with or without a dual mobility cup (DM THA) reducing the risk of dislocation, and hemiarthroplasties. In the absence of clear recommendations regarding the type of implant to be used and the scarcity of studies comparing HA and DM THA, we conducted a monocentric comparative retrospective study using the propensity score method to compare DM THA versus HA on recently displaced femoral neck fractures: (1) survival and risk of dislocation, (2) functional results, (3) mortality.

HYPOTHESIS

The rate of dislocation of THA fitted with a DM cup is lower than that of HA.

PATIENTS AND METHODS

We retrospectively identified 112 patients in the HA group and 153 patients in the DM THA group who underwent an emergency arthroplasty for a displaced cervical fracture between 2010 and 2013. The minimum follow-up was 5 years (range, 5-9 years). The mean age at surgery was 81 years (range, 55-101 years). Elective surgery patients (n=2), hardware fractures (n=10), pathological fractures of the femoral neck (n=6), associated fractures (n=3), and revision surgeries (n=5) were excluded. The primary outcome measure was instability. Clinical follow-up was performed by the WOMAC score and the risk of mortality was determined after adjusting for confounding factors using the propensity score method.

RESULTS

After adjustment by the propensity score, the dislocation rate at 2-years was 2.2% (n=3/153) in the dual mobility THA group and 6.3% (n=7/112) in the HA group (OR=0.34 [95% CI: 0.06-1.96] (p=0.23)). After adjustment by the propensity score, the mean WOMAC score was 8.20 (±6.56) in the THA group, compared to 10.78±3.92 on average in the HA group (p=0.031). After adjustment by the propensity score, we did not find any significant difference in the reoperation rate without changing implants and revisions, and postoperative complications. After adjustment by the propensity score, mortality was significantly higher in the HA group 45.5% (n=69/152) versus 91.5% (n=102/112) in the HA group (OR=0.50 [95% CI: 0.25-0.98] (p=0.042)).

DISCUSSION

Few studies have compared these two types of implant in the context of trauma. Although the results of our study are not significant regarding the risk of dislocation, the use of a dual mobility cup seems to be a very satisfactory solution in this trauma context.

LEVEL OF EVIDENCE

III; comparative retrospective cohort.

Comparable Minimum 2-Year Patient-Reported Outcome Scores Between Circumferential and Segmental Labral Reconstruction for the Management of Irreparable Labral Tear and Femoroacetabular Impingement Syndrome in the Primary Setting: A Propensity-Matched Study

PURPOSE

To compare minimum 2-year follow-up patient-reported outcome scores (PROs) in patients who underwent primary acetabular circumferential and segmental labral reconstruction for irreparable labral tears and femoroacetabular impingement syndrome (FAIS).

METHODS

Data were reviewed from August 2010 to December 2017. Patients with primary labral reconstruction and minimum 2-year follow-up for the modified Harris Hip Score (mHHS), Non-Arthritic Hip Score (NAHS), Hip Outcome Score-Sports Specific Subscale (HOS-SSS), and visual analog scale (VAS) for pain were included. Circumferential and segmental reconstruction were selected in each case based on the extent of the labral pathology. Exclusion criteria were previous ipsilateral hip surgery/conditions, dysplasia, or Tönnis grade >1. Patients were propensity matched 1:1 based on age, sex, and body mass index. Secondary surgeries were reported. The P value was set at <.05.

RESULTS

In total, 144 hips were eligible, and 17 hips were lost to follow-up, leaving 127 hips (88.2%) for analysis. Eighty hips underwent a segmental reconstruction, and 47 hips underwent a circumferential reconstruction. Forty-seven hips with circumferential reconstruction were matched to 47 hips with segmental reconstruction. The average follow-up and age for the segmental and circumferential groups were 29.0 ± 7.8 and 27.9 ± 7.0 months (P = .732) and 43.1 ± 9.4 and 44.7 ± 10.2 years (P = .442) respectively. The segmental and circumferential groups were 48.9% and 51.1% female, respectively. The groups achieved significant and comparable improvement for all PROs and rates of secondary surgeries. No differences were found for achieving the minimal clinically important difference (MCID) and the patient acceptable symptomatic state (PASS). The MCIDs for the segmental and circumferential groups were 76.7% and 77.8% for the mHHS, 64.9% and 77.8% for the HOS-SSS, 71.1% and 68.9% for the VAS, and 68.9% and 73.9% for the NAHS, respectively. The PASSs for the segmental and circumferential groups were 78.3% and 73.3% for the mHHS, 55.3% and 55.0% for the HOS-SSS, and 75.6% and 71.1% for the International Hip Outcome Tool 12, respectively.

CONCLUSIONS

At minimum 2-year follow-up, patients who underwent primary hip arthroscopy for either circumferential or segmental labral reconstruction for irreparable labra and FAIS reported significant improvement and similar postoperative scores for all PROs, with no difference in psychometric outcomes and rate of secondary surgeries. A customized approach, using the extent of the irreparable labral tear, seems to be an appropriate strategy.

LEVEL OF EVIDENCE

Level III, retrospective comparative therapeutic trial.

Trauma Risk Score Matching for Observational Studies in Orthopedic Trauma

OBJECTIVES

To determine if matching by trauma risk score is non-inferior to matching by chronic comorbidities and/or a combination of demographic and patient characteristics in observational studies of acute trauma in a hip fracture model.

DESIGN

Retrospective cohort study SETTING: Level-1 Trauma Center PATIENTS: 1,590 hip fracture [AO/OTA 31A and 31B] patients age 55 and over treated between October 2014 and February 2020 at 4 hospitals within a single academic medical center.

INTERVENTION

Repeatedly matching randomized subsets of patients by (1) Score for Trauma Triage in Geriatric and Middle-Aged (STTGMA), (2) Charlson Comorbidity Index (CCI), or (3) a combination of sex, age, CCI and body mass index (BMI).

MAIN OUTCOME MEASUREMENTS

"Matching failures" where rate of significant differences in variables of matched cohorts exceeds the 5% expected by chance.

RESULTS

STTGMA and combination matching resulted in no "matching failures". Matching by CCI alone resulted in "matching failures" of BMI, ASA class, STTGMA, major complications, sepsis, pneumonia, acute respiratory failure, and 90-day readmission.

CONCLUSIONS

STTGMA matching in observational cohort studies is less likely to yield significant differences of demographics and outcomes than CCI matching. STTGMA matching is noninferior to matching a combination of demographic variables optimized for each treatment cohort. STTGMA matching is apt to reflect equipoise of health at admission and outcome likelihood in observational cohort studies of orthopedic trauma, while maintaining consistent weighting of demographic and injury characteristic variables that may expand the generalizability of these studies.

LEVEL OF EVIDENCE

Level III.

Ataluren delays loss of ambulation and respiratory decline in nonsense mutation Duchenne muscular dystrophy patients

Aim: We investigated the effect of ataluren plus standard of care (SoC) on age at loss of ambulation (LoA) and respiratory decline in patients with nonsense mutation Duchenne muscular dystrophy (nmDMD) versus patients with DMD on SoC alone. Patients & methods: Study 019 was a long-term Phase III study of ataluren safety in nmDMD patients with a history of ataluren exposure. Propensity score matching identified Study 019 and CINRG DNHS patients similar in disease progression predictors. Results & conclusion: Ataluren plus SoC was associated with a 2.2-year delay in age at LoA (p = 0.0006), and a 3.0-year delay in decline of predicted forced vital capacity to <60% in nonambulatory patients (p = 0.0004), versus SoC. Ataluren plus SoC delays disease progression and benefits ambulatory and nonambulatory patients with nmDMD. ClinicalTrials.gov: NCT01557400.

Comparison of Short-Term Clinical Results and Radiologic Changes Between Two Different Minimally Invasive Decompressive Surgical Methods for Lumbar Canal Stenosis: Lumbar Spinous Process Splitting Laminectomy and Trans-Interspinous Lumbar Decompression

STUDY DESIGN

A multicenter, retrospective study.

OBJECTIVE

To clarify the clinical and radiological effects of removing interspinous contextures in lumbar decompression surgery for patients with lumbar spinal stenosis.

SUMMARY OF BACKGROUND DATA

There have seldom been reports that have compared both clinical results and radiological changes among minimally invasive decompression methods.

METHODS

Consecutive 52 patients underwent lumbar spinous process-splitting laminectomy (LSPSL), following which 50 patients underwent trans-interspinous lumbar decompression (TISLD). All patients presented with cauda equina type of lumbar spinal stenosis and underwent a minimum 1-year follow-up. The Japanese Orthopaedic Association (JOA) score and Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (JOABPEQ) score were evaluated to determine the extent of daily living activities. Propensity score (PS)-matched analysis was used to match patients' age and preoperative JOA scores between the two groups. Lumbar lordosis (LL), disc height (DH), segmental range of motion (ROM), and vertebral anterior translation were measured by functional lumbar lateral x-ray, and changes between preoperative and 1-year postoperative values were evaluated.

RESULTS

Twenty-nine pairs of patients were selected by PS-matching. Mean JOA scores increased from 14.4 to 23.5 (mean recovery rate was 62.3%) in the LSPSL group and from 14.0 to 23.2 (61.3%) in the TISLD group at preoperative and 1-year follow-up, respectively. There were no significant differences in clinical results and changes in LL, ROM, and vertebral anterior translation in each group. The DH at L4/5 level at 1-year after surgery revealed significant decrease in the TISLD group compared with the LSPSL group. There was a correlation between preoperative DH and DH decrease in the LSPSL group, but not in TISLD group.

CONCLUSION

Removal of interspinous contextures did not influence clinical outcomes at 1 year after surgery, but it may be likely to cause disc height loss when it applied at the L4/5 level.Level of Evidence: 3.

Outpatient Surgical Fixation of Proximal Humerus Fractures Can Be Performed Without Increased Rates of Short-Term Complications or Readmissions

OBJECTIVE

To delineate differences in short-term complications between outpatient versus inpatient open reduction and internal fixation (ORIF) of proximal humerus fractures.

DESIGN

Retrospective database review.

SETTING

Hospitals participating in the American College of Surgeons National Surgical Quality Improvement Program database.

PATIENTS

Patients in the National Surgical Quality Improvement Program database with proximal humerus fractures from 2005 to 2017.

INTERVENTION

Proximal humerus fracture ORIF.

MAIN OUTCOME MEASUREMENTS

Thirty-day readmission, reoperation, thromboembolic events, and other complications.

RESULTS

In total, 920 outpatient and 2490 inpatient ORIF cases were identified. The proportion of outpatient proximal humerus fracture ORIF increased throughout the years from 6.67% in 2007 to 34.89% in 2017. Each outpatient case was propensity-score-matched with one inpatient case by age, sex, functional status, American Society of Anesthesiologists classification, smoking status, diabetes mellitus type, hypertension, chronic obstructive pulmonary disease, and dyspnea on exertion. After matching, there were 920 outpatient and 920 inpatient cases. Statistical analysis revealed no significant difference in complications including reoperation (1.63% vs. 2.50%), thromboembolic events (0.65% vs. 0.65%), and 30-day readmissions (2.93% vs. 2.69%) between outpatient versus matched inpatient procedures (all P > 0.05). The only significant finding was a lower rate of blood transfusion in outpatient procedures (0.54%) compared with inpatient procedures (4.02%) (P < 0.001).

CONCLUSIONS

The perioperative outcomes assessed here support the conclusion that ORIF for proximal humerus fractures can be performed in the outpatient setting without increased rates of 30-day perioperative complications or readmissions compared with inpatient procedures. However, it is worth noting that the majority of outpatient cases were younger than the average geriatric proximal humerus fracture patient.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Minimum 5-Year Outcomes for Revision Hip Arthroscopy With a Prospective Subanalysis Against a Propensity-Matched Control Primary Group

BACKGROUND

There is a paucity of midterm outcome data on hip revision arthroscopic surgery.

PURPOSE

(1) To report minimum 5-year patient-reported outcome measurement scores (PROMSs) in patients who underwent revision hip arthroscopy, (2) to compare minimum 5-year PROMSs with a propensity-matched control group that underwent primary hip arthroscopy, and (3) to compare the rate of achieving the minimal clinically important difference (MCID) at minimum 5-year follow-up between the revision group and the propensity-matched control primary group.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Data were prospectively collected between June 2008 and April 2014. Patients were included who underwent revision hip arthroscopy with preoperative and minimum 5-year follow-up scores for the modified Harris Hip Score (mHHS), Non-arthritic Hip Score (NAHS), Hip Outcome Score-Sports Specific Subscale (HOS-SSS), and visual analog scale (VAS) for pain. Patients with Tönnis grade >1 or with hip conditions such as avascular necrosis, Legg-Calve-Perthes disease, Ehlers-Danlos syndrome, and pigmented villonodular synovitis were excluded. A subanalysis was performed against a propensity-matched control group that underwent primary surgery. Groups were propensity matched in a 1:2 ratio for sex, age, body mass index, and follow-up time.

RESULTS

A total of 127 revision arthroscopies (113 patients) were included, and the mean ± SD follow-up time was 72.8 ± 23.3 months. The revision group was 74.0% female, and the average age and body mass index were 34.9 ± 12.4 years and 24.8 ± 4.2, respectively. The revision group demonstrated improvement for all PROMSs and reached the MCID for the mHHS (66.1%), HOS-SSS (68.4%), NAHS (66.9%), and VAS (80.0%). All revision cases were propensity matched to 254 primary arthroscopy cases. PROMSs in the revision group were lower than those of the control group before and after surgery. Delta values were similar between groups for all PROMSs. There were no differences in rates of achieving the MCID. The relative risk of arthroplasty conversion was 2.6 (95% CI, 1.5-4.6) for the revision group as compared with the primary group.

CONCLUSION

Significant improvement in all PROMSs, including the VAS, and high patient satisfaction at minimum 5-year follow-up were reported after revision hip arthroscopy. A high proportion of patients in the revision cohort reached the MCID for the mHHS, HOS-SSS, NAHS, and VAS, with similar rates and magnitudes of improvement relative to the control group. As expected, these data indicate that patients undergoing primary hip arthroscopy have higher PROMSs before and after surgery and lower rates of conversion to arthroplasty.

Factors Associated with Knee Arthroplasty in a Knee Osteoarthritis Patient Cohort Treated with Intra-articular Injections of Hylan G-F 20

Hylan G-F 20 viscosupplementation can be used to treat knee osteoarthritis pain. This study evaluated time to knee arthroplasty (KA), KA risk factors, and health care resource utilization in patients aged ≥18 years with claims in the Optum Clinformatics Data Mart database (2006-2016) for knee osteoarthritis treated with at least one course of hylan G-F 20. Kaplan-Meier analysis estimated KA risk from osteoarthritis diagnosis and first hylan G-F 20 treatment. KA risk factors were determined using multivariate Cox regression. Among 62,033 patients treated with hylan G-F 20 and/or hylan G-F 20 single intra-articular injection, 60 to 64% did not undergo KA 8 years following first injection. KA risk factors from time of osteoarthritis diagnosis and first hylan G-F 20 treatment were similar: increased age, fewer comorbidities, fewer hylan G-F 20 treatments, female sex, and no ultrasound/fluoroscopy for injection guidance. Patients who underwent KA versus those who did not had more office visits and claims for opioids, nonsteroidal anti-inflammatory drugs, and physical therapy. Patients less likely to undergo KA were younger (<40 years), had more comorbidities, received more courses of hylan G-F 20, were males, or received ultrasound/fluoroscopic injection guidance. Patients who did not receive KA versus those who did used fewer health care resources.

Computer-Assisted Navigation Is Associated With Decreased Rates of Hardware-Related Revision After Instrumented Posterior Lumbar Fusion

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

To (1) define utilization trends for navigated instrumented posterior lumbar fusion (PLF), (2) compare reasons and rates of revision at 30-day, 60-day, 90-day, and 1-year follow-up, and (3) compare 90-day perioperative complications between navigated versus conventional instrumented PLF.

METHODS

Patients who underwent navigated or conventional instrumented PLF were identified from the Humana insurance database using the PearlDiver Patient Records between 2007-2017. Usage of navigation was characterized. Patient demographics and operative characteristics (number of levels fused, interbody usage) were compared between the 2 treatment groups. Propensity score matching was done and comparisons were made for revision rates at different follow-up periods (categorized by reasons) and other 90-day perioperative complications.

RESULTS

This study included 1,648 navigated and 23 429 conventional instrumented PLF. Navigated cases increased over the years studied to approximately 10% in 2017. Statistical analysis after propensity score matching revealed significantly lower rates of hardware-related revision at 90-day follow-up in the navigated cohort (0.49% versus 1.15%, P = .033). At 1-year follow-up, the navigated cohort continued to have significantly lower rates of hardware-related revision (1.70% versus 2.73%, P = .044) as well as all cause revision (2.67% versus 4.00%, P = .032). There were no statistical differences between the 2 cohorts in any of the 90-day perioperative complications studied, such as cellulitis and blood transfusion (P > .05 for all).

CONCLUSIONS

These findings suggest that navigation is associated with reductions in hardware-related revisions after instrumented PLF. However, these results should be interpreted cautiously in the setting of potential confounding by other unmeasured variables.

Anatomic features in SCAD assessed by CCT: A propensity score matching case control study

PURPOSE

Spontaneous coronary artery dissection (SCAD) may occur in middle age population without any cardiovascular risk factor. We retrospectively evaluated anatomic features of 11 patients with SCAD using a coronary arteries computed tomography (CCT), compared to age and sex balanced patients who underwent CCT.

MATERIAL AND METHODS

CCT was performed in 11 patients (7 females and 4 males) as follow-up in patients with SCAD (left anterior descending - LAD or circumflex artery - Cx) and compared, using the propensity score matching analysis, with 11 healthy patients. Several anatomic features were evaluated: Left main (LM) length, angle between descending coronary artery (LAD) and its first branch, angle between LAD and LM, distance from the annulus to RCA (a-RCA distance) and LM (a-LM distance) ostia and their ratio; ratio between LM length and length a-LM and tortuosity score of the vessel with SCAD. A fluid dynamic analysis has been performed to evaluate the effects on shear stress of vessels wall.

RESULTS

LM length was significantly shorter in patients with SCAD versus healthy subjects (P=0.01) as well as LM length/a-LM (P=0.03) and the angle between LAD and the first adjacent branch was sharper (P<0.01). Tortuosity score showed a statistically significant difference between groups (P<0.001). Fluid dynamic analysis demonstrates that, in SCAD group, an angle<90 degree is present at the first bifurcation and it can be a cause of increased strain on vessel wall in patients with high tortuosity of coronary artery.

CONCLUSION

Tortuosity and angle between the LAD and the adjacent arterial branch combined may determine increased shear stress on the vessel wall that increases the risk of SCAD.

Modular Tibial Stem Use and Risk of Revision for Aseptic Loosening in Cemented Primary Total Knee Arthroplasty

BACKGROUND

Modular tibial stem extensions in total knee arthroplasty (TKA) are designed to reduce the risk of aseptic loosening of the tibial base plate. However, these implants add significant cost and an evaluation of their effectiveness in reducing this risk of loosening has not been studied in a large cohort. We sought to evaluate modular tibial stem utilization in primary TKA.

METHODS

We conducted a cohort study using our integrated healthcare system's Total Joint Replacement Registry. Patients who underwent cemented primary TKA were identified (2009-2019). Propensity scores were used to 1:1 match patients without to those with a stem extension. Cox proportional-hazards regression was used to evaluate the risk for revision due to aseptic loosening.

RESULTS

Ten thousand four hundred seventy six TKA with a modular tibial stem were matched to 10,476 TKA without a tibial stem. Stem utilization associated with a lower risk of revision for loosening across all postoperative follow-up (hazard ratio = 0.38, 95% confidence interval = 0.17-0.85).

CONCLUSION

In a matched cohort study, we observed presence of a stem extension was associated with a lower risk of revision for aseptic loosening. Further study to identify specific risk factors for aseptic loosening and confirm the findings presented here are warranted.

LEVEL OF EVIDENCE

Level III.

The effect of emerging molecular and genetic therapies on cardiopulmonary disease in Duchenne muscular dystrophy

Gene therapy is an attractive approach being intensively studied to prevent muscle deterioration in patients with Duchenne muscular dystrophy. While clinical trials are only in early stages, initial reports are promising for its effects on ambulation. Cardiopulmonary failure, however, is the most common cause of mortality in Duchenne muscular dystrophy (DMD) patients, and little is known regarding the prospects for gene therapy on alleviating DMD-associated cardiomyopathy and respiratory failure. Here we review current knowledge regarding effects of gene therapy on DMD cardiomyopathy and discuss respiratory endpoints that should be considered as outcome measures in future clinical trials.

Long-Term Results of Total Hip Arthroplasty in Young Patients With Osteonecrosis After Allogeneic Bone Marrow Transplantation for Hematological Disease: A Multicenter, Propensity-Matched Cohort Study With a Mean 11-Year Follow-Up

BACKGROUND

The number of young patients with hematological disease requiring total hip arthroplasty (THA) is expected to increase. We aimed to investigate the long-term THA outcomes in patients with osteonecrosis of the femoral head (ONFH) following allogeneic bone marrow transplantation (BMT) for hematological disease.

METHODS

All patients who underwent THA for osteonecrosis after BMT from 1997 to 2012 were identified at 2 institutions. Using propensity scores, 75 THAs in 45 patients were matched for age, gender, body mass index, American Society of Anesthesiologists score, and year of surgery with 75 THAs in 58 patients with idiopathic ONFH without a history of hematological disease (1:1 ratio). The mean age at surgery was 36.7 years and 52% were men. Clinical and radiographic evaluations were performed and clinical scores were obtained at last follow-up. Kaplan-Meier analyses were used to compare survivorship.

RESULTS

At a mean follow-up of 10.6 ± 3.5 years, clinical, radiographic, and survivorship outcomes, and the Harris hip scores were similar between both groups. The 13-year survivorship for all-cause revision was 93.4% for the BMT group and 95% for the control group (P = .928). No significant differences were observed between groups in the rates of reoperation (4% vs 5.3%, P = 1.000), 90-day readmission (all 5.3%), or overall mortality (4.4% vs 1.7%, P = .681). No hips had periprosthetic joint infection or septic loosening in either group. Osteolysis occurred in none of the BMT patients and in 2 hips (2.7%) of the control patients (P = .497).

CONCLUSION

This large cohort multicenter survey at 11-year follow-up shows that contemporary cementless THA in young hematological disease patients after allogeneic BMT is not associated with a higher risk for surgical complications, revision, reoperation, readmission, and mortality compared to a matched cohort of idiopathic ONFH.

Revision Hip Arthroscopy in the Borderline Dysplastic Population: Reporting Outcomes With Minimum 2-Year Follow-up, With a Subanalysis Against a Propensity-Matched Nondysplastic Control Group

BACKGROUND

Hip arthroscopy in patients with borderline dysplasia continues to be surrounded by controversy. Even more controversial is the management of the failed hip arthroscopy in this population. There is a paucity of studies in contemporary literature regarding outcomes after arthroscopic revision surgery.

PURPOSE

(1) To report minimum 2-year patient-reported outcome (PRO) scores in patients with borderline dysplasia who underwent revision hip arthroscopy and (2) to compare these PRO scores with those of a propensity-matched control group without dysplasia who underwent revision hip arthroscopy.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Data were prospectively collected between August 2009 and November 2017. Inclusion criteria were revision arthroscopic surgery, capsular plication, and baseline and minimum 2-year follow-up for the following PROs: modified Harris Hip Score (mHHS), Nonarthritic Hip Score (NAHS), Hip Outcome Score-Sports Specific Subscale (HOS-SSS), and visual analog scale (VAS) for pain. Patients with Tönnis grade >1 or previous hip conditions were excluded. Two groups were created: a study group with borderline dysplasia (lateral center-edge angle [LCEA], 18°-25°) and a control group without dysplasia (LCEA, 25°-40°). Groups were propensity-matched in a 1:3 ratio for sex, age, body mass index, and follow-up time.

RESULTS

A total of 22 revision borderline dysplastic hips (21 patients) had a minimum 2-year follow-up during the study period. Patients in this group reported significant improvements for all PROs from baseline and achieved the minimal clinically important difference (MCID) for the mHHS at a rate of 70%. Moreover, 21 borderline dysplastic hips (21 patients) were matched to 63 control hips (63 patients). Mean LCEA for the study and control groups was 22.6 ± 1.7 and 32.0 ± 5.0, respectively. Both groups reported similar improvement in all PROs. The rate for achieving the MCID for the mHHS and VAS was similar between groups; however, the control group had higher rates of meeting the MCID for the HOS-SSS and NAHS (P = .042 and P = .025, respectively). The rates of conversion to hip arthroplasty were 7.9% (n = 5) in the control group and 23.8% (n = 5) in the borderline dysplasia propensity-matched group (P = .052). The rate of re-revision arthroscopy was 11.1% (n = 7) in the control group and 19.0% (n = 4) on the borderline dysplasia group (P = .350).

CONCLUSION

After revision hip arthroscopy, significant improvement was obtained for all PROs in patients with borderline dysplasia at a minimum 2-year follow-up. Moreover, outcomes, patient satisfaction, the rate for achieving the MCID for the mHHS and VAS, and the rate for secondary surgery were similar to those of a propensity-matched control group without dysplasia. Nevertheless, there was a nonsignificant trend toward higher secondary procedures in the study group; therefore, arthroscopic revision surgery in the borderline patients should be approached with measured prognosis.

Circumferential Labral Reconstruction for Irreparable Labral Tears in the Primary Setting: Minimum 2-Year Outcomes With a Nested Matched-Pair Labral Repair Control Group

PURPOSE

(1) To report minimum 2-year patient-reported outcome (PRO) scores of primary circumferential acetabular labral reconstruction using anterior tibialis allograft and the knotless pull-through technique in the setting of femoroacetabular impingement syndrome (FAIS) and irreparable labral tears and (2) to compare these PROs with a matched-pair primary labral repair group.

METHODS

Data were prospectively collected and retrospectively reviewed. Patients were included if they underwent primary circumferential labral reconstruction with anterior tibialis tendon allograft during February 2016 to April 2017 for irreparable labral tears and FAIS and had preoperative and minimum 2-year follow-up for modified Harris Hip Score (mHHS), Hip Outcome Score-Sport-Specific Subscale, Non-arthritic Hip Score, International Hip Outcome Tool 12 (iHOT-12), 12-Item Short Form Health Survey physical component and mental component, Veterans RAND 12-Item Health Survey physical component and mental component, and visual analog scale for pain. The exclusion criteria were previous ipsilateral hip conditions or surgical procedures, Tönnis grade 2 or higher, or dysplasia (lateral center-edge angle ≤ 18°). Labral tears were considered irreparable if the labrum appeared (1) to be mostly or completely calcified and (2) to be inadequate (nonviable) and not amenable for labral repair. The reconstruction group was matched 1:3 based on age, sex, and body mass index to a benchmark control group of hips undergoing labral repair from the same period. The minimal clinically important difference and patient acceptable symptomatic state for the mHHS and iHOT-12 score were calculated.

RESULTS

A total of 37 hips (37 patients) underwent circumferential labral reconstruction. There were 19 female patients (51.4%) and 18 male patients (48.6%). The mean age was 45.6 ± 11.6 years, and the average body mass index was 27.1 ± 5. At minimum 2-year follow-up, the circumferential labral reconstruction group showed statistically significant improvements in the mHHS, Non-arthritic Hip Score, Hip Outcome Score-Sport-Specific Subscale, iHOT-12 score, and visual analog scale score. All hips in the reconstruction group were successfully matched to 111 labral repair hips. At latest follow-up, improvements in all PROs between the 2 groups were comparable. The revision rates were 0% and 3.6% in the reconstruction and repair groups, respectively.

CONCLUSIONS

After primary hip arthroscopy, primary circumferential labral reconstruction using anterior tibialis allograft and the knotless pull-through technique in the setting of FAIS and irreparable labral tears resulted in significant improvements in several PROs at minimum 2-year follow-up and high patient satisfaction. Primary circumferential labral reconstruction reached comparable functional outcomes to those of a benchmark matched-pair primary labral repair control group.

LEVEL OF EVIDENCE

Level III, case-control study.

Does preoperative dipyridamole-thallium scanning reduce 90-day cardiac complications and 1-year mortality in patients with femoral neck fractures undergoing hemiarthroplasty?

Background

This study aimed to evaluate the effect of dipyridamole-thallium scanning (DTS) on the rates of 90-day cardiac complications and 1-year mortality in patients with a femoral neck fracture treated with hemiarthroplasty.

Methods

Between 2008 and 2015, 844 consecutive patients who underwent cemented or cementless hemiarthroplasty were identified from the database of a single level-one medical center. One-hundred and thirteen patients (13%) underwent DTS prior to surgery, and 731 patients (87%) did not. Patient characteristics, comorbidities, surgical variables, and length of the delay until surgery were recorded. A propensity score-matched cohort was utilized to reduce recruitment bias in a 1:3 ratio of DTS group to control group, and multivariate logistic regression was performed to control confounding variables.

Results

The incidence of 90-day cardiac complications was 19.5% in the DTS group and 15.6% in the control group (p = 0.343) among 452 patients after propensity score-matching. The 1-year mortality rate (10.6% vs 13.3%, p = 0.462) was similar in the two groups. In the propensity score-matched patients, utilization of DTS was not associated with a reduction in the rate of 90-day cardiac complications (matched cohort, adjusted odds ratio [aOR] = 1.32; 95% confidence interval [CI] 0.75–2.33, p = 0.332) or the 1-year mortality rate (aOR = 0.62; 95% CI 0.27–1.42, p = 0.259). Risk factors for cardiac complications included an American Society of Anesthesiologists grade ≥ 3 (OR 3.19, 95% CI 1.44–7.08, p = 0.004) and pre-existing cardiac comorbidities (OR 5.56, 95% CI 3.35–9.25, p < 0.001). Risk factors for 1-year mortality were a long time to surgery (aOR 1.15, 95% CI 1.06–1.25, p = 0.001), a greater age (aOR 1.05, 95% CI 1.00 to 1.10, p = 0.040), a low body mass index (BMI; aOR 0.89, 95% CI 0.81–0.98, p = 0.015), and the presence of renal disease (aOR 4.43, 95% CI 1.71–11.46, p = 0.002).

Discussion

Preoperative DTS was not associated with reductions in the rates of 90-day cardiac complications or 1-year mortality in patients with a femoral neck fracture undergoing hemiarthroplasty. The necessity for DTS should be re-evaluated in elderly patients with femoral neck fractures, given that this increases the length of the delay until surgery.

Level of evidence

Prognostic level III

The Impact of Resident Involvement on Postoperative Complications After Shoulder Arthroscopy: A Propensity-Matched Analysis

PURPOSE

Shoulder arthroscopy is the second most frequently performed procedure by orthopaedic surgeons taking the American Board of Orthopaedic Surgery part II examination. However, the impact of resident involvement on outcomes after shoulder arthroscopy is poorly understood. The aim of this study was to investigate whether resident involvement in shoulder arthroscopic procedures affects postoperative complication rates and surgical time using propensity score-matched cohorts.

METHODS

The American College of Surgeons National Surgical Quality Improvement Program registry was queried to identify patients who underwent common shoulder arthroscopic procedures between 2006 and 2012. Cases without information on resident involvement, treatment of septic arthritis or osteomyelitis of the shoulder, or concomitant open or miniopen procedures were excluded from the study. A 1:1 propensity score match was used based on demographic and comorbidity factors to match cases with resident involvement to nonresident cases. Patient demographics, comorbidities, surgical time, length of hospital stay, and 30-day postoperative complications were compared between the two groups.

RESULTS

Overall, 15,857 patients who underwent shoulder arthroscopy were identified. After propensity score matching, 3474 cases (50% with resident involvement) were included. Appropriate matching was verified with no difference in demographic or health characteristics. No significant differences in the overall rate of 30-day complications was noted in resident-involved versus nonresident group (P = 0.576). No significant difference was observed in postoperative surgical or medical complications. Resident involvement was significantly longer surgical time (75.9 ± 35.9 versus 75.1 ± 40.5 minutes, P = 0.03) when compared with cases performed without a resident.

CONCLUSIONS

Resident involvement in shoulder arthroscopy is not associated with increased risk for medical or surgical 30-day postoperative complications. Resident participation in shoulder arthroscopy cases did increase surgical time; however, this finding is likely clinically insignificant.

A Systematic Review of Methods Used for Confounding Adjustment in Observational Economic Evaluations in Cardiology Conducted between 2013 and 2017

Background. Observational economic evaluations (i.e., economic evaluations in which treatment allocation is not randomized) are prone to confounding bias. Prior reviews published in 2013 have shown that adjusting for confounding is poorly done, if done at all. Although these reviews raised awareness on the issues, it is unclear if their results improved the methodological quality of future work. We therefore aimed to investigate whether and how confounding was accounted for in recently published observational economic evaluations in the field of cardiology. Methods. We performed a systematic review of PubMed, Embase, Cochrane Library, Web of Science, and PsycInfo databases using a set of Medical Subject Headings and keywords covering topics in "observational economic evaluations in health within humans" and "cardiovascular diseases." Any study published in either English or French between January 1, 2013, and December 31, 2017, addressing our search criteria was eligible for inclusion in our review. Our protocol was registered with PROSPERO (CRD42018112391). Results. Forty-two (0.6%) out of 7523 unique citations met our inclusion criteria. Fewer than half of the selected studies adjusted for confounding (n = 19 [45.2%]). Of those that adjusted for confounding, propensity score matching (n = 8 [42.1%]) and other matching-based approaches were favored (n = 8 [42.1%]). Our results also highlighted that most authors who adjusted for confounding rarely justified their methodological choices. Conclusion. Our results indicate that adjustment for confounding is often ignored when conducting an observational economic evaluation. Continued knowledge translation efforts aimed at improving researchers' knowledge regarding confounding bias and methods aimed at addressing this issue are required and should be supported by journal editors.

Total Hip Arthroplasty for Developmental Dysplasia of Hip vs Osteoarthritis: A Propensity Matched Pair Analysis

Background

The purpose of this study was to use the American College of Surgeons National Surgical Quality Improvement Program to compare the perioperative and postoperative outcomes after total hip arthroplasty (THA) for DDH and primary OA via a propensity-matched pair analysis and the valuation of THA between both groups.

Material and Methods

All patients who underwent THA between 2008 and 2016 were identified from National Surgical Quality Improvement Program database via the current procedural terminology (CPT) code. Patients were further identified and stratified based on International Statistical Classification of Diseases and Related Health Problems-9/International Statistical Classification of Diseases and Related Health Problems-10 diagnosis codes for primary OA (n = 115,166) and DDH (n = 603), which included codes for congenital hip dislocation, hip dysplasia, or juvenile osteochondrosis. Demographic variables were used to create 557 propensity-matched pairs.

Results

The DDH group was associated with a significantly longer operative time (120.3 vs 95.9 min), higher postoperative transfusion rate (12% vs 6.6%), and longer hospital length of stay (2.8 vs 2.5 days) compared with the primary OA group (P < .001, P < .001, and P = .002, respectively). There were no statistically significant differences found between the two groups with respect to inpatient complications, discharge disposition (P = .123), readmissions (P = .615), or reoperations (P = .404).

Conclusions

Health policy makers should be cognizant of the higher complexity of THA for DDH when determining whether DDH and primary OA should be in the same bundle. Owing to the limitations of our data set, all the observed associations are likely an underestimate of the true risk posed to patients with severe DDH, as these patients were unable to be stratified in the present analysis.

Hips With Acetabular Retroversion Can Be Safely Treated With Advanced Arthroscopic Techniques Without Anteverting Periacetabular Osteotomy: Midterm Outcomes With Propensity-Matched Control Group

BACKGROUND

Different options, from reverse (anteverting) periacetabular osteotomy to hip arthroscopy, have been proposed for surgical treatment of femoroacetabular impingement syndrome (FAIS) in the setting of acetabular retroversion.

PURPOSE

(1) To report and analyze midterm patient-reported outcome scores (PROs) in patients with FAIS and labral tears in the setting of acetabular retroversion after isolated hip arthroscopy and (2) to compare these PROs with those of a propensity-matched control group without acetabular retroversion.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Prospectively collected data were retrospectively reviewed for patients who underwent hip arthroscopy for FAIS and labral tear treatment between June 2008 and March 2014. Inclusion criteria were as follows: acetabular retroversion, pre- and postoperative PROs for modified Harris Hip Score (mHHS), Non-arthritic Hip Score, Hip Outcome Score-Sports Specific Scale (HOS-SSS), and visual analog scale (VAS). Propensity score matching was utilized to identify a control group without acetabular retroversion matched 1:1 with similar age, sex, body mass index, acetabular and femoral head Outerbridge grade, preoperative lateral center-edge angle, and labral treatment. Patient acceptable symptomatic state (PASS) and/or minimal clinically important difference (MCID) for the mHHS, HOS-SSS, International Hip Outcome Tool-12, and VAS was calculated.

RESULTS

A total of 205 hips with acetabular retroversion were matched to a control group. The groups showed no difference in demographic variables. The retroversion group was composed of 139 female and 66 male hips, with a mean ± SD age of 23.81 ± 7.28 years and follow-up time of 65.24 ± 20.31 months. Intraoperative diagnostic data and procedures performed were similar between groups, except more femoroplasties were performed in the retroversion group. Significant improvements for the mHHS, Non-arthritic Hip Score, HOS-SSS, and VAS were seen for both groups at a mean 5-year follow-up. The proportion of patients who reached the PASS and MCID were similar.

CONCLUSION

In the setting of FAIS and labral tears, patients with acetabular retroversion can be safely treated with advanced hip arthroscopic techniques without reverse (anteverting) periacetabular osteotomy in a high-volume surgeon's hands. Patients with acetabular retroversion demonstrated favorable PROs at midterm follow-up. Furthermore, the proportion of patients reaching the MCID and PASS for several PROs were comparable with those of a propensity-matched control group without acetabular retroversion.

Antibiotic-Loaded Hydrogel Coating to Reduce Early Postsurgical Infections in Aseptic Hip Revision Surgery: A Retrospective, Matched Case-Control Study

Periprosthetic joint infections (PJIs) are a cause of frequent implant failure in revision hip replacement surgery. The purpose of this study is to evaluate the onset of early postoperative infections in patients who underwent hip surgery with cementless prostheses treated with an antibiotic loaded hydrogel on their surface, in addition to systemic prophylaxis, and compare them to a control group. The secondary objective was to evaluate the onset of any local and systemic adverse effects and interference with bone ingrowth processes and functional recovery. A retrospective observational study was conducted on patients who underwent revision hip surgery by performing a 1:1 match between patients treated with an antibiotic hydrogel (ALH) and the control patients. The incidence of PJIs was assessed with a minimum of six months follow-up. Seventeen patients treated with the ALH were compared with 17 patients from the control group. No PJIs were reported in the ALH group versus the six cases encountered in the control group (p < 0.0001). No significant differences were reported with regard to prosthetic osseointegration and functional results, nor were there side effects in the ALH group. Despite the low sample size, the use of on-site prophylaxis with ALH has proven effective and safe in reducing the risk of PJIs in patients with a high risk for infections. Further studies are needed to validate these results in other implant-related surgeries.

Reduced survival of total knee arthroplasty after previous unicompartmental knee arthroplasty compared with previous high tibial osteotomy: a propensity-score weighted mid-term cohort study based on 2,133 observations from the Danish Knee Arthroplasty Registry

Background and purpose - Both medial unicompartmental knee arthroplasties (UKA) and high tibial osteotomies (HTO) are reliable treatments for isolated medial knee osteoarthritis. However, both may with time need conversion to a total knee arthroplasty (TKA). We conducted the largest nationwide registry comparison of the survival of TKA following UKA with TKA following HTO.Patients and methods - From the Danish Knee Arthroplasty Registry, aseptic conversions to TKA from UKA and TKA converted from HTO within the period of 1997-2018 were retrieved. The Kaplan-Meier method and the Cox proportional hazards regression were used to estimate the survival and hazard ratio (HR) for revision, considering confounding by indication utilizing propensity-score based inverse probability of treatment weighting (PS-IPTW).Results - PS-IPTW yielded a well-balanced pseudo-cohort (standard mean difference (SMD) < 0.1 for all covariates, except implant supplementation) of 963.8 TKAs following UKA and 1139.1 TKAs following HTO. The survival of TKA following UKA was significantly less than that of TKA following HTO with a 5-year estimated survival of 0.88 (95% confidence interval (CI) 0.85-0.90) and 0.94 (CI 0.93-0.96), respectively. The differences in survival corresponded to an implant-supplementation adjusted HR of 2.7 (CI 2.4-3.1) for TKA following UKA compared with TKA following HTO.Interpretation - Previous UKA more than doubled the revision risk of a subsequent TKA compared with previous HTO. This potential risk should be considered in the shared treatment decision of patients who are candidates for both UKA and HTO.

An Intact Ligamentum Teres Predicts a Superior Prognosis in Patients With Borderline Dysplasia: A Matched-Pair Controlled Study With Minimum 5-Year Outcomes After Hip Arthroscopic Surgery

BACKGROUND

Hip arthroscopic surgery in patients with borderline dysplasia continues to be controversial. In addition, it has been suggested that ligamentum teres (LT) tears may lead to inferior short-term patient-reported outcomes (PROs) when compared with a match-controlled group.

PURPOSES

(1) To report minimum 5-year PROs in patients with borderline dysplasia and LT tears who underwent hip arthroscopic surgery and (2) to compare these PROs to those of a matched-pair control group of patients with borderline dysplastic hips without LT tears.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Data were prospectively collected for patients who underwent hip arthroscopic surgery between September 2008 and August 2013. Patients were included if they had a preoperative diagnosis of borderline dysplasia (lateral center-edge angle [LCEA], 18°-25°) and had preoperative and minimum 5-year postoperative modified Harris Hip Score (mHHS), Nonarthritic Hip Score (NAHS), and visual analog scale (VAS) for pain scores. Exclusion criteria were osteoarthritis of Tönnis grade >1, previous hip conditions, any previous ipsilateral hip surgery, or workers' compensation status. There were 2 borderline dysplastic groups created. An LT tear group was matched 1:1 to a control group (no LT tear) with similar age, sex, body mass index (BMI), and laterality via propensity score matching. Significance was set at P < .05.

RESULTS

A total of 24 patients with an LT tear (24 hips) were matched to 24 patients without an LT tear (24 hips). There was no significant difference in age, sex, BMI, or laterality between groups. The mean age was 36.2 ± 17.2 and 34.9 ± 15.9 years for the control and LT tear groups, respectively (P = .783). There were 17 (70.8%) and 16 (66.7%) female patients in the control and LT tear groups, respectively, and the mean preoperative LCEA was 23.3° and 22.2° in the control and LT tear groups, respectively. No differences were observed between groups in baseline PROs, intraoperative findings, or surgical procedures. LT debridement was performed in 17 (70.8%) patients in the LT tear group compared with 0 (0.0%) in the control group. Also, 5-year postoperative PROs were comparable in both groups, with the control group exhibiting superior Veterans RAND 12-Item Health Survey (VR-12) mental (P = .041) and Short Form-12 (SF-12) mental (P = .042) scores. Finally, hips with an intact LT were significantly more likely (P = .022) to achieve the patient acceptable symptomatic state (PASS) for the mHHS (100.0% and 75.0%, respectively). No significant differences were present between the groups for the minimal clinically important difference (MCID) of the mHHS (P = .140), MCID of the Hip Outcome Score-Sport-Specific Subscale (HOS-SSS) (P = .550), or PASS of the HOS-SSS (P = .390).

CONCLUSION

After hip arthroscopic surgery, patients with borderline dysplasia and LT tears demonstrated favorable PROs at a minimum 5-year follow-up. Outcomes were similar to a matched-pair control group without LT tears, with the group with intact LTs showing higher VR-12 mental and SF-12 mental scores. Furthermore, patients with borderline dysplasia and intact LTs were significantly more likely to achieve the PASS for the mHHS.

Safety and effectiveness of ataluren: comparison of results from the STRIDE Registry and CINRG DMD Natural History Study

Aim:

Strategic Targeting of Registries and International Database of Excellence (STRIDE) is an ongoing, multicenter registry providing real-world evidence regarding ataluren use in patients with nonsense mutation Duchenne muscular dystrophy (nmDMD). We examined the effectiveness of ataluren + standard of care (SoC) in the registry versus SoC alone in the Cooperative International Neuromuscular Research Group (CINRG) Duchenne Natural History Study (DNHS), DMD genotype–phenotype/–ataluren benefit correlations and ataluren safety.

Patients & methods:

Propensity score matching was performed to identify STRIDE and CINRG DNHS patients who were comparable in established disease progression predictors (registry cut-off date, 9 July 2018).

Results & conclusion:

Kaplan–Meier analyses demonstrated that ataluren + SoC significantly delayed age at loss of ambulation and age at worsening performance in timed function tests versus SoC alone (p ≤ 0.05). There were no DMD genotype–phenotype/ataluren benefit correlations. Ataluren was well tolerated. These results indicate that ataluren + SoC delays functional milestones of DMD progression in patients with nmDMD in routine clinical practice. ClinicalTrials.gov identifier: NCT02369731.

ClinicalTrials.gov identifier: NCT02369731.

Creating value in spine surgery: using patient reported outcomes to compare the short-term impact of different orthopedic surgical procedures

BACKGROUND CONTEXT

Society increasingly asks Medicine to create "value" for patients. As health-care costs rise, this question will become more important. Debate exists regarding the relative "value" of many surgical procedures, including spinal surgery. Comparison of the relative value that patients experience after different orthopedic procedures is theoretical, but informs the ongoing debate.

METHODS

The Patient Reported Outcome Measurement Information System (PROMIS) assessments for Physical Function, Pain Interference, and Depression are routinely collected in our orthopedic clinics. Patients who underwent lumbar discectomy (DSC) or arthroscopic anterior cruciate ligament reconstruction (ACLR) were retrospectively identified. Data relating to PROMIS domains, patient demographics, and other relevant encounter details were extracted. The primary outcomes were (1) preoperative PROMIS domain scores, (2) scores at a minimum of 40 days postoperatively for DSC patients and 133 days postoperatively for ACLR patients, and (3) the change in scores with surgery. Propensity score matching identified age-, sex-, race-, and comorbidity-matched groups from each cohort. Chi-square tests and nonparametric Kruskal-Wallis tests compared the distribution of outcomes and characteristics. Multivariate linear regression models with interactions between the matched cohort and operative phase estimated the change in the outcomes scores between the two cohorts and controlled for the baseline differences between them.

RESULTS

Before surgery, the DSC cohort had lower physical function, higher pain interference and higher depression scores as compared with the ACLR cohort. This pattern remained postoperatively, indicating less desirable outcomes for DSC patients. However, after controlling for their baseline scores, DSC patients experienced significantly greater improvements after surgery of 3.84 (95% CI 1.08-6.60; p=.01), -4.87 (95% CI -7.52 to -2.23; p<.001), and -2.95 (95% CI -5.70 to -0.21; p=.04) points in their physical function, pain interference, and depression scores, respectively, as compared with ACLR patients.

CONCLUSIONS

Based upon PROMIS assessments at short-term follow-up, DSC patients receive a larger benefit from surgery than ACLR despite the overall less desirable postoperative PROMIS scores in the DSC cohort. This result, while theoretical, informs the debate regarding the comparative value of DSC to patients.

Is Intra-Articular Injection of Synvisc Associated with a Delay to Knee Arthroplasty in Patients with Knee Osteoarthritis?

OBJECTIVE

There is debate about the effectiveness of intra-articular (IA) hyaluronic acid (HA) injections. We asked the following questions: (1) What is the epidemiology of IA HA use in knee arthroplasty (KA) patients? (2) Is Synvisc associated with a delay to KA? (3) Is there a difference in the delay to KA with the number of HA courses?

DESIGN

The Optum Clinformatics data set (2006-June 2016) was used to identify patients with knee osteoarthritis (OA). Patients who did not receive IA HA were identified, along with those who received Synvisc or non-Synvisc HA. The median duration from knee OA to KA was compared using quantile regression modeling with propensity score weighting. The trend in time to KA with each HA course was evaluated.

RESULTS

Of 4,027,848 knee OA patients, 141,305 patients underwent KA. Overall median time from knee OA diagnosis to KA was 1.2 years (average: 1.9 ± 1.9 years; interquartile range of 0.4-2.8 years). HA patients had significantly longer adjusted median time to KA by at least 7 months (P < 0.001). After adjusting for the time to HA and number of injections, Synvisc patients had 1.7 months longer time to KA than non-Synvisc HA patients (P < 0.001). There was a trend toward longer time to KA with more HA courses.

CONCLUSIONS

Most KA patients did not use HA (73.7%) and when received, it was associated with a longer median time to KA by at least 7 months, though the cause and effect could not be examined. The delay to KA increased with more HA courses.

Comparison of Ivor Lewis esophagectomy and Sweet esophagectomy for the treatment of middle-lower esophageal squamous cell carcinoma

Background

For cancer of the middle and/or lower segment of thoracic esophagus, the Ivor Lewis esophagectomy is the mainstream standard surgery, whereas the Sweet procedure is widely used in China. As no consensus has been reached about the choice of different thoracic approaches, we designed this retrospective study to investigate and compare oncological benefits of the two surgical approaches.

Methods

After propensity score matching, 150 patients who underwent the Sweet or Ivor Lewis esophagectomy from August 2003 to December 2009 in the Beijing Cancer Hospital were reviewed. We compared the postoperative recovery, nutritional parameters, and survival of the two different surgical approaches.

Results

The 5-year overall survival (OS) rate for the whole group was 48.5%, and the 10-year OS rate was 35.6%. The Ivor Lewis group had a longer operation time, longer duration of chest tube drainage, and a larger volume of total thoracic drainage. No significant differences were found between the two groups in terms of the duration of systemic inflammatory response syndrome (SIRS), length of postoperative hospital stay, duration of postoperative nasogastric tube use, incidence of major complications, and nutritional status after the esophagectomy. The OS rates were similar in both groups.

Conclusions

The Sweet and Ivor Lewis esophagectomy are both safe and effective. A change of the surgical incision may not be the best way to increase survival, and the choice of surgical procedure should depend on the preference of the thoracic surgeon to secure the safety of the operation.

Comparison of the accelerometer-based navigation system with conventional instruments for total knee arthroplasty: a propensity score-matched analysis

BACKGROUND

The accelerometer-based navigation (ABN) system is an emerging navigation system for total knee arthroplasty (TKA). This study aimed to determine whether the ABN system could improve the accuracy of mechanical alignment, component positioning, and short-term clinical outcomes for TKA when compared to conventional instruments (CON).

METHODS

A total of 204 patients were selected and divided into two groups (CON: 135, ABN: 69) after applying the inclusion and exclusion criteria. Then, 1:1 propensity score matching was performed for age, gender, body mass index, hip-knee-ankle angle (HKA), Knee Society Score (KSS), Western Ontario and McMaster Universities (WOMAC) score, and follow-up times. A total of 82 consecutive patients (82 knees) underwent total knee arthroplasty using ABN (n = 41) or CON (n = 41) were enrolled in this study. The postoperative HKA, frontal femoral component (FFC) angle, frontal tibial component (FTC) angle, lateral femoral flexion (LFF) angle, and lateral tibial component (LTC) angle were compared between the two groups to evaluate mechanical alignment and component positioning. Additional clinical parameters, including haemoglobin reduction, the KSS, and the WOMAC score, were assessed at the final follow-up (the mean follow-up period was 20.9 months in the CON group and 21.2 months in the ABN group).

RESULTS

The ABN group had a significantly improved mean absolute deviation of HKA (P = 0.033), FFC (P = 0.004), FTC (P = 0.017), LFF (P = 0.023), and LTC (P = 0.031) compared to those of the CON group. The numbers of FFCs and LTCs within 3° were significantly different (P = 0.021, P = 0.023, respectively) between the two groups. However, no differences in the numbers of FTCs within 3° (P = 0.166) and LFF within 3° (P = 0.556) were found. The ABN group had a significantly higher KS function score (P = 0.032), and the pain and stiffness scores were significantly different (P = 0.034, P = 0.020, respectively) between the two groups. Moreover, the ABN system could reduce hidden blood loss postoperatively. However, no difference was found in the KS knee score and the total WOMAC score between the two groups.

CONCLUSION

This study demonstrates that ABN system improved TKA mechanical alignment and component positioning and decreased the hidden blood loss postoperatively compared to conventional instruments. However, no significant differences were found in short-term clinical outcomes between ABN and conventional instruments at the final follow-up. However, whether this system contributes to revision rates and long-term clinical outcomes requires further study.