Background: Establishing imaging registries for large patient cohorts is challenging because manual labeling is tedious and relying solely on DICOM (digital imaging and communications in medicine) metadata can result in errors. We endeavored to establish an automated hip and pelvic radiography registry of total hip arthroplasty (THA) patients by utilizing deep-learning pipelines. The aims of the study were (1) to utilize these automated pipelines to identify all pelvic and hip radiographs with appropriate annotation of laterality and presence or absence of implants, and (2) to automatically measure acetabular component inclination and version for THA images. Methods: We retrospectively retrieved 846,988 hip and pelvic radiography DICOM files from 20,378 patients who underwent primary or revision THA performed at our institution from 2000 to 2020. Metadata for the files were screened followed by extraction of imaging data. Two deep-learning algorithms (an EfficientNetB3 classifier and a YOLOv5 object detector) were developed to automatically determine the radiographic appearance of all files. Additional deep-learning algorithms were utilized to automatically measure the acetabular angles on anteroposterior pelvic and lateral hip radiographs. Algorithm performance was compared with that of human annotators on a random test sample of 5,000 radiographs. Results: Deep-learning algorithms enabled appropriate exclusion of 209,332 DICOM files (24.7%) as misclassified non-hip/pelvic radiographs or having corrupted pixel data. The final registry was automatically curated and annotated in <8 hours and included 168,551 anteroposterior pelvic, 176,890 anteroposterior hip, 174,637 lateral hip, and 117,578 oblique hip radiographs. The algorithms achieved 99.9% accuracy, 99.6% precision, 99.5% recall, and a 99.6% F1 score in determining the radiograph appearance. Conclusions: We developed a highly accurate series of deep-learning algorithms to rapidly curate and annotate THA patient radiographs. This efficient pipeline can be utilized by other institutions or registries to construct radiography databases for patient care, longitudinal surveillance, and large-scale research. The stepwise approach for establishing a radiography registry can further be utilized as a workflow guide for other anatomic areas. Level of Evidence: Diagnostic Level IV . See Instructions for Authors for a complete description of levels of evidence.
Creation of a Total Hip Arthroplasty Patient-Specific Dislocation Risk Calculator
Background: Many risk factors have been described for dislocation following total hip arthroplasty (THA), yet a patient-specific risk assessment tool remains elusive. The purpose of this study was to develop a high-dimensional, patient-specific risk-stratification nomogram that allows dynamic risk modification based on operative decisions. Methods: In this study, 29,349 THAs, including 21,978 primary and 7371 revision cases, performed between 1998 and 2018 were evaluated. During a mean 6-year follow-up, 1521 THAs were followed by a dislocation. Patients were characterized, through individual-chart review, according to non-modifiable factors (demographics, indication for THA, spine disease, prior spine surgery, and neurologic disease) and modifiable operative decisions (operative approach, femoral head diameter, and type of acetabular liner [standard, elevated, constrained, or dual-mobility]). Multivariable regression models and nomograms were developed with dislocation as a binary outcome at 1 year and 5 years postoperatively. Results: Dislocation risk, based on patient-specific comorbidities and operative decisions, was wide-ranging—from 0.3% to 13% at 1 year and from 0.4% to 19% at 5 years after primary THA, and from 2% to 32% at 1 year and from 3% to 42% at 5 years after revision THA. In the primary-THA group, the direct anterior approach (hazard ratio [HR] = 0.27) and lateral approach (HR = 0.58) decreased the dislocation risk compared with the posterior approach. After adjusting for the approach in that group, the combination of a ≥36-mm-diameter femoral head and an elevated liner yielded the largest decrease in dislocation risk (HR = 0.28), followed by dual-mobility constructs (HR = 0.48). In the patients who underwent revision THA, the adjusted risk of dislocation was most markedly decreased by the use of a dual-mobility construct (HR = 0.40), followed by a ≥36-mm femoral head and an elevated liner (HR = 0.88). The adjusted risk of dislocation after revision THA was decreased by acetabular revision (HR = 0.58), irrespective of whether other components were revised. Conclusions: Our patient-specific dislocation risk calculator, which was strengthened by our use of a robust multivariable model that accounted for comorbidities associated with instability, demonstrated wide-ranging patient-specific risks based on comorbidity profiles. The resultant nomograms can be used as a screening tool to identify patients at high risk for dislocation following THA and to individualize operative decisions for evidence-based risk mitigation. Level of Evidence: Prognostic Level IV . See Instructions for Authors for a complete description of levels of evidence.
Deep Learning for Radiographic Measurement of Femoral Component Subsidence Following Total Hip Arthroplasty
Abstract Aims The objective of this study is to longitudinally assess sociodemographic and psychological correlates of increased alcohol use during the coronavirus disease of 2019 (COVID-19) period among adolescents and young adults. Methods Pre-COVID period is defined as the 1-year period on or before 31 March 2020, and during-COVID period is defined as the period from 1st April 2020 to 30 March 2021. Univariable logistic regression models are used to evaluate the association of demographic characteristics, Area Deprivation Index (ADI), rurality, changes in Patient Health Questionnaire (PHQ-9) and Generalized Anxiety Disorder (GAD-7) scale severity, and the risk of increased alcohol consumption (binge drinking, number of drinks and drinking regularity) from pre-COVID to during-COVID period. Results and conclusion Our study found that worsened anxiety symptoms, older age, being in college and current cigarette smoking status were associated with increased alcohol use among youth during the pandemic year. Socioeconomic position (measured by ADI) and rural status were not found to be associated with increased alcohol use among adolescents and young adults.
Redefining the 3D Topography of the Acetabular Safe Zone
Background: Dislocation is the most common reason for early revision following total hip arthroplasty (THA). More than 40 years ago, Lewinnek et al. proposed an acetabular “safe zone” to avoid dislocation. While novel at the time, their study was substantially limited according to modern standards. The purpose of this study was to determine optimal acetabular cup positioning during THA as well as the effect of surgical approach on the topography of the acetabular safe zone and the hazard of dislocation. Methods: Primary THAs that had been performed at a single institution from 2000 to 2017 were reviewed. Acetabular inclination and anteversion were measured using an artificial intelligence neural network; they were validated with performance testing and comparison with blinded grading by 2 orthopaedic surgeons. Patient demographics and dislocation were noted during follow-up. Multivariable Cox proportional-hazards regression, including multidimensional analysis, was performed to define the 3D topography of the acetabular safe zone and its association with surgical approach. Results: We followed 9,907 THAs in 8,081 patients (4,166 women and 3,915 men; 64 ± 13 years of age) for a mean of 5 ± 3 years (range: 2 to 16); 316 hips (3%) sustained a dislocation during follow-up. The mean acetabular inclination was 44° ± 7° and the mean anteversion was 32° ± 9°. Patients who did not sustain a dislocation had a mean anteversion of 32° ± 9° (median, 32°), with the historic ideal anteversion of 15° observed to be only in the third percentile among non-dislocating THAs (p < 0.001). Multivariable modeling demonstrated the lowest dislocation hazards at an inclination of 37° and an anteversion of 27°, with an ideal modern safe zone of 27° to 47° of inclination and 18° to 38° of anteversion. Three-dimensional analysis demonstrated a similar safe-zone location but significantly different safe-zone topography among surgical approaches (p = 0.03) and sexes (p = 0.02). Conclusions: Optimal acetabular positioning differs significantly from historic values, with increased anteversion providing decreased dislocation risk. Additionally, surgical approach and patient sex demonstrated clear effects on 3D safe-zone topography. Further study is needed to characterize the 3D interaction between acetabular positioning and spinopelvic as well as femoral-sided parameters. Level of Evidence: Prognostic Level III . See Instructions for Authors for a complete description of levels of evidence.
The Epidemiology of Psoriatic Arthritis Over Five Decades: A Population‐Based Study
ObjectiveTo determine the incidence of psoriatic arthritis (PsA) in a US population and describe trends in incidence and mortality over 5 decades.MethodsThe previously identified population‐based cohort that included Olmsted County, Minnesota residents ≥18 years of age who fulfilled PsA criteria during 1970–1999 was extended to include patients with incident PsA during 2000–2017. Age‐ and sex‐specific incidence rates and point prevalence, adjusted to the 2010 US White population, were reported.ResultsThere were 164 incident cases of PsA in 2000–2017 (mean ± SD age 46.4 ± 12.0 years; 47% female). The overall age‐ and sex‐adjusted annual incidence of PsA per 100,000 population was 8.5 (95% confidence interval [95% CI] 7.2–9.8) and was higher in men (9.3 [95% CI 7.4–11.3]) than women (7.7 [95% CI 5.9–9.4]) in 2000–2017. Overall incidence was highest in the 40–59 years age group. The incidence rate was relatively stable during 2000–2017, with no evidence of an overall increase or an increase in men only (but a modest increase of 3% per year in women), compared to 1970–1999 when a 4%‐per‐year increase in incidence was observed. Point prevalence was 181.8 per 100,000 population (95% CI 156.5–207.1) in 2015. The percentage of women among those with PsA increased from 39% in 1970–1999 and 41% in 2000–2009 to 54% in 2010–2017 (P = 0.08). Overall survival in PsA did not differ from the general population (standardized mortality ratio 0.85 [95% CI 0.61–1.15]).ConclusionThe incidence of PsA in this predominantly White US population was stable in 2000–2017, in contrast to previous years. However, an increasing proportion of women with PsA was found in this study.
Direct Inpatient Medical Costs of Operative Treatment of Periprosthetic Hip and Knee Infections Are Twofold Higher Than Those of Aseptic Revisions
Background: Periprosthetic joint infections (PJIs) following total hip arthroplasty (THA) and total knee arthroplasty (TKA) are associated with substantial morbidity. A better understanding of the costs of PJI treatment can inform prevention, treatment, and reimbursement strategies. The purpose of the present study was to describe direct inpatient medical costs associated with the treatment of hip and knee PJI. Methods: At a single tertiary care institution, 176 hips and 266 knees that underwent 2-stage revisions for the treatment of PJI from 2009 to 2015 were compared with 1,611 hips and 1,276 knees that underwent revisions for aseptic indications. In addition, 84 hips and 137 knees that underwent irrigation and debridement (I&D) with partial component exchange were compared with 39 hips and 138 knees that underwent partial component exchange for aseptic indications. Line-item details of services billed during hospitalization were retrieved, and standardized direct medical costs were calculated in 2018 inflation-adjusted dollars. Results: The mean direct medical cost of 2-stage revision THA performed for the treatment of PJI was significantly higher than that of aseptic revision THA ($58,369 compared with $22,846, p < 0.001). Similarly, the cost of 2-stage revision TKA performed for the treatment of PJI was significantly higher than that of aseptic revision TKA ($56,900 compared with $24,630, p < 0.001). Even when the total costs of aseptic revisions were doubled for a representative comparison with 2-stage procedures, the costs of PJI procedures were 15% to 28% higher than those of the doubled costs of aseptic revisions (p < 0.001). The mean direct medical cost of I&D procedures for PJI was about twofold higher than of partial component exchange for aseptic indications. Conclusions: The direct medical costs of operative treatment of PJI following THA and TKA are twofold higher than the costs of similar aseptic revisions. The high economic burden of PJI warrants efforts to reduce the incidence of PJI. Reimbursement schemes should account for the high costs of treating PJI in order to ensure sustainable patient care. Level of Evidence: Economic Level IV . See Instructions for Authors for a complete description of levels of evidence.
Costs of open, arthroscopic and combined surgery for developmental dysplasia of the hip
Abstract A variety of options exist for management of patients with developmental dysplasia of the hip (DDH). Most studies to date have focused on clinical outcomes; however, there are currently no data on comparative cost of these techniques. The purpose of this study was to evaluate in-hospital costs between patients managed with periacetabular osteotomy, hip arthroscopy or a combination for DDH. One hundred and nine patients were included: 35 PAO + HA, 32 PAO and 42 HA. There were no significant differences in the demographic parameters. Operative times were significantly different between groups with a mean of 52 min for PAO, 100 min for HA and 155 min for PAO + HA, (P < 0.001). Total direct medical costs were calculated and adjusted to nationally representative unit costs in 2017 inflation-adjusted dollars. Total in-hospital costs were significantly different between each of the three treatment groups. PAO + HA was the most expensive with a median of $21 852, followed by PAO with a median of $15 124, followed by HA with a median of $11 582 (P < 0.001). There was a significant difference between outpatient median costs of $11 385 compared with $24 320 for inpatients (P < 0.001). Procedures with greater complexity were more expensive. However, a change from outpatient to inpatient status with HA moved that group from the least expensive to similar to PAO and PAO + HA. These data provide an important complement to clinical outcomes reports as surgeons and policymakers aim to provide optimal value.
Use of Natural Language Processing Algorithms to Identify Common Data Elements in Operative Notes for Total Hip Arthroplasty
Update This article was updated on December 6, 2019, because of a previous error. On page 1936, in Table VII, “Performance of the Bearing Surface Algorithm,” the row that had read “Bearing surface predicted by algorithm” now reads “Bearing surface predicted by algorithm*.” An erratum has been published: J Bone Joint Surg Am. 2020 Jan 2;102(1):e4. Update This article was updated on March 31, 2020, because of a previous error. On page 1934, in Table IV (“THA Bearing Surface-Related Keywords in Operative Notes”), the row that had read “Femoral stem; stem; HFx-stem; femoral component; femoral component/stem; permanent prosthesis; stem fem cemented” now reads “Femoral head; ball; delta head; delta ceramic head; ion treated; BIOLOX delta; ceramic head; ceramic femoral head; ceramic offset head; ceramic (size) head; alumina ceramic head; alumina prosthetic head; alumna ceramic head; BIOLOX ceramic head; BIOLOX delta head; BIOLOX femoral head; BIOLOX delta ceramic head.” An erratum has been published: J Bone Joint Surg Am. 2020 May 6;102(9):e43. Background: Manual chart review is labor-intensive and requires specialized knowledge possessed by highly trained medical professionals. Natural language processing (NLP) tools are distinctive in their ability to extract critical information from raw text in electronic health records (EHRs). As a proof of concept for the potential application of this technology, we examined the ability of NLP to correctly identify common elements described by surgeons in operative notes for total hip arthroplasty (THA). Methods: We evaluated primary THAs that had been performed at a single academic institution from 2000 to 2015. A training sample of operative reports was randomly selected to develop prototype NLP algorithms, and additional operative reports were randomly selected as the test sample. Three separate algorithms were created with rules aimed at capturing (1) the operative approach, (2) the fixation method, and (3) the bearing surface category. The algorithms were applied to operative notes to evaluate the language used by 29 different surgeons at our center and were applied to EHR data from outside facilities to determine external validity. Accuracy statistics were calculated with use of manual chart review as the gold standard. Results: The operative approach algorithm demonstrated an accuracy of 99.2% (95% confidence interval [CI], 97.1% to 99.9%). The fixation technique algorithm demonstrated an accuracy of 90.7% (95% CI, 86.8% to 93.8%). The bearing surface algorithm demonstrated an accuracy of 95.8% (95% CI, 92.7% to 97.8%). Additionally, the NLP algorithms applied to operative reports from other institutions yielded comparable performance, demonstrating external validity. Conclusions: NLP-enabled algorithms are a promising alternative to the current gold standard of manual chart review for identifying common data elements from orthopaedic operative notes. The present study provides a proof of concept for use of NLP techniques in clinical research studies and registry-development endeavors to reliably extract data of interest in an expeditious and cost-effective manner.
Revision Total Hip Arthroplasty for the Treatment of Fracture: More Expensive, More Complications, Same Diagnosis-Related Groups
Background: Revision total hip arthroplasty (revision THA) occurs for a wide variety of indications and in the United States it is coded under Diagnosis-Related Groups (DRGs) 466, 467, and 468, which do not account for revision etiology, a potentially substantial driver of cost. This study investigates revision THA costs and 30-day complications by indication, both locally and nationally. Methods: Hospitalization costs and complication rates for 1,422 aseptic revision THAs performed at a high-volume center between 2009 and 2014 were retrospectively reviewed. Additionally, charges for 28,133 revision THAs in the National Inpatient Sample (NIS) were converted to costs using the Healthcare Cost and Utilization Project cost-to-charge ratios, and 30-day complication rates for 3,224 revision THAs were obtained with use of the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP). Costs and complications were compared between revision THAs performed for fracture, wear/loosening, and dislocation/instability with use of simultaneous and pairwise comparisons and a multivariable model accounting for American Society of Anesthesiologists (ASA) score, age, and sex. Results: Local hospitalization costs for fracture (median, $25,672) were significantly higher than those for wear/loosening ($20,228; p < 0.001) or dislocation/instability ($17,911; p < 0.001), with differences remaining significant even after adjusting for patient comorbidities (p < 0.001). NIS costs for fracture (median, $27,596) were higher than those for other aseptic indications (wear/loosening: $21,176, p < 0.001; dislocation/instability: $16,891, p< 0.001). Local 30-day orthopaedic complication rates for fracture (20.7%) were higher those than for dislocation/instability (9.0%; p = 0.007) and similar to those for wear/loosening (17.6%; p = 0.434). Nationally, combined medical and surgical complication rates for fracture (71.3% of patients with ≥1 complication) were significantly higher than those for wear/loosening (35.2%; p < 0.001) or dislocation/instability (35.1%; p < 0.001). Conclusions: Hospitalization costs for revision THA for fracture were 33% to 48% higher than for all other aseptic revision THAs, both locally and nationally. This increased cost persisted even after multivariable comorbidity adjustment, the current DRG basis for stratifying revision THA reimbursement. Additionally, 30-day complication rates suggest that increased resource utilization for fracture patients continues even after discharge. Indication-specific coding and reimbursement systems are necessary to maintain sustainable access to revision THA for all patients. Level of Evidence: Prognostic Level III . See Instructions for Authors for a complete description of levels of evidence.