Abstract Purpose The purpose of this systematic review was to compare the inter‐ and intra‐observer reliability of Kellgren–Lawrence (KL) grading versus minimum joint space width (mJSW) measurement on knee radiographs, and to examine the influence of rater type, radiographic view and atlas‐based training. Methods A systematic search of PubMed/MEDLINE, Embase, Scopus and Web of Science was conducted through July 2025 following Preferred Reporting Items for Systematic reviews and Meta‐Analyses (PRISMA) guidelines. Studies reporting inter‐ and/or intra‐observer reliability for KL or mJSW on standard knee radiographs were included. Extracted data included kappa ( κ ) and intraclass correlation coefficient (ICC) values, rater expertise, radiographic view and atlas usage. Raters were categorized as expert, trainee/non‐expert or artificial intelligence (AI)‐assisted/automated. Results Twenty‐four studies (10,394 radiographs) met the inclusion criteria. Inter‐observer reliability was generally higher for mJSW (mean ICC = 0.82 ± 0.17) compared with KL (mean k = 0.72 ± 0.17), with similar trends observed for intra‐observer reliability. Experts and AI‐assisted systems outperformed trainees/non‐experts for both metrics. Reliability improved with semiflexed posteroanterior/Rosenberg views and atlas‐guided training. Conclusion This systematic review demonstrates that mJSW measurement generally shows higher reproducibility than KL grading. Reliability improved with expertise, standardized imaging and structured training, and AI‐assisted approaches performed comparably to expert raters. Quantitative mJSW should complement KL grading, particularly when combined with alignment measures, to enhance consistency and clinical relevance of radiographic assessment. Level of Evidence Level III.
Comparison of Large Language Models with Rules-Based Natural Language Processing Algorithms for Extracting Data from Operative Notes
Background: We aimed to develop automated data extraction pipelines with large language models (LLMs) to extract registry data from total hip arthroplasty (THA) operative notes and compare the performance with that of existing natural language processing (NLP) algorithms. Methods: We randomly sampled 1,000 primary THA cases from our institutional registry. Two human annotators manually reviewed each operative note for 3 data points: surgical approach, bearing surface, and fixation technique. All labeled THA notes were split into the development set (n = 239) and the testing set (n = 719). We developed a custom data extraction pipeline for each data point by combining an iteratively customized prompt with an LLM. The performance was compared with that of existing rules-based NLP algorithms. Results: The accuracy of LLMs was superior to that of NLP algorithms for all data points: surgical approach (96% compared with 94%), bearing surface (89% compared with 74%), and fixation technique (96% compared with 95%). Furthermore, the LLM accurately inferred the bearing surface for 80% of the notes that were ambiguous about the bearing surface. Conclusions: We developed LLM pipelines for extracting 3 registry-relevant data points from THA operative notes, demonstrating superior performance to existing NLP algorithms. Clinical Relevance: LLMs have the potential to impact clinical care, including the evaluation of electronic medical record free-text data. As registries serve as a cornerstone of orthopaedic evidence, this work demonstrates promise for LLMs to simplify, improve, and democratize the construction of registry databases from operative notes.
An algorithm for automated femoral leg length and offset calculations on pelvis radiographs
Introduction: Manual measurement of leg length (LL) and offset can be tedious. This study developed an automated algorithm for measuring LL and offset from pre- and postoperative AP pelvis radiographs in a large cohort of THA patients. Methods: Using a deep learning model trained on 1100 total AP pelvis radiographs, an algorithm was developed to calculate LL and offset. Algorithm measurements were compared with manual measurements by 4 raters on a sample of 100 pre- and postoperative image pairs. Inter- and intra-rater consistency was calculated using the intraclass correlation coefficient (ICC). The algorithm was applied to calculate the pre- and postoperative LL and offset discrepancies and the change in LL and offset bilaterally in a cohort of 15,951 image pairs. Results: ICC values between the algorithm and human raters ranged from 0.83 to 0.88 for offset measurements and 0.92 to 0.97 for LL measurements. Human raters demonstrated good-to-excellent inter-rater ICC and uniformly excellent intra-rater ICC. Entire database measurements demonstrated shorter LLs for arthritic joints versus the contralateral leg preoperatively and reduced LL discrepancy post-arthroplasty. Conclusions: We present a deep learning algorithm for calculating LL and offset using AP pelvis radiographs. This tool can support population-level studies and may assist operative management.
Artificial intelligence (AI) is increasingly shaping pediatric spine care, leveraging its rapid advancements in healthcare to improve efficiency, accuracy, and disease understanding. Moreover, machine learning and deep learning excel at detecting complex patterns. This holds promise in processing spinal deformity data, with the potential to surpass traditional statistical methods in predictive accuracy. Challenges persist, however, including unclear clinical implementation guidelines, limited model transparency, and ethical concerns surrounding data privacy and bias. Small sample sizes and the need for larger, diverse datasets further complicate integration. In order to realize AI’s transformative potential in pediatric spine care, these critical obstacles must be addressed for effective and ethical clinical adoption. This review examines the role of AI through applications such as image sorting, surgical outcome prediction, forecasting of spinal curve progression, and vertebral volumetric analysis using deep reasoning. It also explores possible intraoperative contributions from AI, including robotics and optimized screw trajectory planning, and the potential of large language models in clinical practice.
The Timing of Direct Oral Anticoagulant Usage Did Not Impact Outcomes Following Hip Arthroplasty for Femoral Neck Fractures
Background: Orthopaedic surgeons routinely delay surgical management of femoral neck fractures in patients taking direct oral anticoagulants (DOACs) to decrease perioperative bleeding and associated complications. However, this practice contradicts the principles of hip fracture management, as early surgery is associated with morbidity and mortality benefits. The purpose of this study was to quantify the association of DOAC use and perioperative outcomes in patients who underwent hemiarthroplasty (HA) or total hip arthroplasty (THA) for femoral neck fractures. We hypothesized that early surgical intervention on a patient taking a DOAC medication would not lead to worse perioperative outcomes. Methods: A retrospective cohort study was conducted on 2,833 patients who underwent primary THA or HA for femoral neck fractures between December 31, 2017, and January 29, 2024, across our hospital system. The patients taking a DOAC were divided into 3 groups based on the time since the last DOAC intake: 1 day, 2 days, and ≥3 days. Propensity matching was performed 1:1, accounting for age, sex, Elixhauser Comorbidity Index, preoperative chronic kidney disease stage, preoperative hemoglobin, body mass index, and hospital type. Subanalyses utilizing linear and conditional logistic regression models were performed to assess differences in outcomes between the groups that had a DOAC withheld and the control groups. Results: The mean age of all patients was 81 ± 10 years, 1,805 patients (64%) were women, and 207 patients (7%) were taking a DOAC prior to surgery. Despite comparable preoperative and postoperative hemoglobin levels between the groups that had a DOAC withheld and the control groups (all p > 0.05), the patients who had a DOAC withheld for 1 day were more likely to receive a postoperative blood transfusion (23.1% compared with 0%; p = 0.002). This difference in transfusion rate was not observed in other cohorts. There were no differences in medical complications, reoperation, discharge disposition, or mortality between the groups that had a DOAC withheld and the matched controls at any time point. Conclusions: Delaying surgical management due to DOAC medications may be unnecessary in patients undergoing arthroplasty for femoral neck fractures. Consideration should be given to adjusting transfusion triggers to reduce unwarranted blood transfusions in patients taking a DOAC. Level of Evidence: Therapeutic Level III . See Instructions for Authors for a complete description of levels of evidence.
Isolation of Multiple Positive Cultures at Resection Arthroplasty is a Predictor of Failure Following Reimplantation
Background: Although it is well established that the type of organism can be a risk factor for failure in patients with periprosthetic joint infection (PJI), no study to date has examined the impact of the number of positive cultures on treatment outcomes in patients undergoing 2-stage exchange. The purpose of this multicenter study was to determine the prognostic utility of multiple positive cultures at resection as a predictor of failure following reimplantation. Methods: This retrospective multicenter study identified 437 patients with chronic knee PJI who had undergone 2-stage exchange arthroplasty with a minimum of 1 year of follow-up following reimplantation. PJI was defined with use of the 2013 Musculoskeletal Infection Society (MSIS) criteria. Patients with culture-negative PJI were excluded (n = 138). Treatment failure was defined as either any reoperation for infection or PJI-related mortality. Multivariable regression controlling for risk factors for failure after a 2-stage arthroplasty was performed to determine whether ≥2 positive intraoperative cultures at resection can predict outcomes following reimplantation when compared with a single positive culture. Results: Two hundred and ninety-nine patients were included. At a mean follow-up of 6.2 ± 2.6 years, 48 patients (16.1%) experienced failure. Patients who had a failure were more likely to have had a longer interstage interval (p = 0.038) and were also more likely to have had ≥2 positive cultures at the time of resection arthroplasty (95.8% versus 75.3%; p = 0.001). On regression analysis, ≥2 positive cultures at resection was the only variable that was identified as a risk factor for failure following reimplantation in both the univariate (odds ratio [OR], 7.55 [95% CI, 2.24 to 47.0]; p = 0.006) and multivariable models (OR, 8.12 [95% CI, 2.31 to 51.9]; p = 0.005). Conclusions: This is the first study to examine the impact of the number of positive cultures on outcomes in patients with PJI. We found that the presence of ≥2 positive cultures at resection was an indicator of a poor prognosis and resulted in a greater than eightfold increase in the risk of treatment failure in patients undergoing a 2-stage exchange. Level of Evidence: Prognostic Level III . See Instructions for Authors for a complete description of levels of evidence.
Genetics of morphological hip abnormalities and their implications for osteoarthritis: a scoping review
Abstract Morphological hip abnormalities (MHAs) significantly influence lifelong prognosis of the hip, contributing to early-onset osteoarthritis and impaired functionality. Developmental dysplasia of the hip (DDH) and femoroacetabular impingement (FAI) represent key pathologies, resulting from insufficient or excessive femoral head coverage, respectively. These abnormalities alter hip biomechanics, leading to structural damage, pain, and accelerated joint degeneration. Advances in genetic research have illuminated the interplay between genetics and mechanical loading in shaping hip morphology. Genes associated with osteoarthritis, DDH, and FAI include COL1A1, MMP13, and IL-6. Genes associated with FAI and osteoarthritis include ADAMTS4. Genes associated with DDH and osteoarthritis include FRZB, CX3CR1, ASPN, DKK1, PDRG1, GDF5, UQCC1, and TGF-β1. The mechanisms linking morphological derangements to symptomatic osteoarthritis remain incompletely understood. Multimodal approaches integrating imaging, biomechanics, and genetics may uncover distinct disease subtypes, enabling personalized interventions. Early detection of MHAs is critical in preventing early-onset osteoarthritis. Incorporating advanced imaging techniques, such as statistical shape modelling, can enhance the understanding of complex 3D hip morphologies and their progression to osteoarthritis. Future research should explore the genetic underpinnings of other morphologic hip conditions, including Slipped Capital Femoral Epiphysis and Legg–Calvé–Perthes disease, to refine preventive and therapeutic strategies. A comprehensive approach combining genetics, imaging, and clinical insights holds promise for mitigating the lifelong impact of MHAs.
Outcomes Following Direct Anterior Approach Total Hip Arthroplasty
Background: The direct anterior approach (DAA) is a popular approach for primary total hip arthroplasty (THA). However, the contemporary outcomes for DAA THA need further elucidation. Therefore, we aimed to describe implant survivorship, complications, and clinical outcomes after DAA THA. Methods: From our multi-institutional total joint registry, 3,184 patients who had undergone 3,698 primary DAA THA between 2010 and 2019 were identified. The identified patients had a mean age of 65 years and a mean body mass index (BMI) of 29 kg/m 2 , and 53% of patients were female. The indications for revision and reoperation and the incidence of complications were collected and analyzed. Potential risk factors, including age, sex, BMI, and high-volume compared with low-volume operating surgeons, were examined. Descriptive statistics and Kaplan-Meier survivorship with Cox regression analyses were performed. Results: At 10 years following primary DAA THA, the cohort had 96% (95% confidence interval [CI], 95% to 98%) survivorship free of any revision and 94% (95% CI, 92% to 96%) survivorship free of any reoperation. The leading indications for revision were periprosthetic joint infection (PJI) (n = 24; 5-year cumulative incidence, 0.93% [95% CI, 0.6% to 1.5%]), periprosthetic fracture (n = 20; 5-year cumulative incidence, 0.62% [95% CI, 0.4% to 1.0%]), and aseptic loosening (n = 14; 11 femoral, 3 acetabular; 5-year cumulative incidence, 0.84% [95% CI, 0.5% to 1.5%]). A BMI of ≥40 kg/m 2 was found to be significantly associated with PJI (hazard ratio [HR], 6.4; p < 0.001), reoperation (HR, 3.5; p < 0.001), and nonoperative complications (HR, 2.3; p = 0.018). Survivorship free of recurrent instability was 99.6% (95% CI, 99.4% to 99.8%) at 5 and 10 years, and the cumulative incidence of revision for instability was 0.14% at 5 years. Conclusions: In one of the largest published series to date, survivorship following DAA THA was satisfactory at early to intermediate follow-up. The leading indications for revision were PJI, periprosthetic fracture, and aseptic loosening. Instability after DAA THA was uncommon and infrequently led to revision. As a note of caution, a BMI of ≥40 kg/m 2 was identified as a risk factor for adverse outcome after DAA THA. Level of Evidence: Therapeutic Level IV . See Instructions for Authors for a complete description of levels of evidence.