Prevalence of anemia and association with outcome in joint arthroplasty - is there a difference between primary and revision cases?

PURPOSE: Anemia has been shown to be a modifiable pre-operative, patient factor associated with outcome following arthroplasty. The aims of this retrospective study were to (1) ascertain the prevalence of preoperative anemia in patients undergoing primary and revision hip and knee arthroplasty at a tertiary referral center and (2) to test the association with outcome and whether it differs between primary and revision cases. METHODS: All hip and knee primary and revision arthroplasties performed at a Canadian academic, tertiary-care, arthroplasty center between 2012 and 2017 were included in this study. The study group consisted of 5944 patients, of which 5251 were primary Total Hip and Knee Arthroplasties or Hip Resurfacings and 693 were revision arthroplasties (65% hip revisions/35% knee revisions). Anemia was classified as per WHO definition (hemoglobin < 130 g/L for men and < 120 g/L for women). All anemic patients were grouped into mild, moderate or severe anemia. Length-of-stay, perioperative transfusion-rate, 90-day readmission, overall complication rate and reoperation rates were recorded. The effect of preoperative anemia and the effect of severity of the anemia was evaluated through multivariable regression analysis controlling for relevant covariates. RESULTS: Preoperatively, 15% (786/5251) of the primary patients and 47% (322/693) of the revision arthroplasty patients were anemic preoperatively. Anemic revision patients were 3.1 times more likely (95% CI: 1.47-6.33) to obtain blood transfusions during the hospital stay, compared to a 4.9 times higher risk in primary patients. The odds ratio to sustain any postoperative complication if anemic was 1.5 times higher (95% CI: 0.73-3.16) in revision patients and 1.7 in primary cases. In addition, the 90-day readmission rate among both groups was 1.6 times higher in anemic patients. Furthermore, anemic revision patients had a 5.3 days longer length of stay (95% CI: 2.63-7.91), compared to only 1 additional day in anemic primary patients (95% CI: 0.69-1.34). CONCLUSION: In this study cohort, the prevalence of anemia in patients awaiting revision arthroplasty was 3 times higher (46.6%) than in primary arthroplasty patients (18.7%). Preoperative anemia was associated with similarly, inferior outcomes in both groups. To reduce postoperative complications and the "burden" associated with anemia, these findings strongly recommend optimizing the preoperative hemoglobin in all arthroplasty patients. However, revision patients are affected more frequently, and particular attention must therefore be taken to this growing group in the future. LEVEL OF EVIDENCE: Level III.

Periprosthetic fracture following anterior approach or dislocation after posterior approach: which one is the lesser evil?

INTRODUCTION: The most common approaches in total hip arthroplasty (THA) have different complication profiles; anterior-approach (AA-THA) has an increased risk of periprosthetic fractures (PPF); posterior-approach (PA-THA) is associated with higher dislocation risk. However, the relative severity of one versus the other is unknown. This study aims to compare outcome of patients who suffered PPF after AA-THA with those that sustained dislocation after PA-THA. METHODS: This is a retrospective, single-center, multi-surgeon, consecutive case-series of primary THA patients. In a cohort of 9867 patients who underwent THA, 79 fulfilled the approach-specific, post-operative complication criteria, of which 44 were PPF after AA-THA and 35 with dislocation after PA-THA (age 67.9 years (range: 38.0-88.1), 58.2% women). Outcome included complication- and revision- rates, and patient-reported outcomes including Oxford Hip Score (OHS). RESULTS: At 5.8 years follow-up (range: 2.0-18.5), reoperation was more common in the dislocation after PA-THA group (23/35 vs. 20/44; p = 0.072). Change of surgical approach occurred in 15/20 of patients with PPF after AA-THA, but none in those with dislocation after PA-THA. Following re-operation, complication rate was greater in the PPF group (9/20 vs. 4/23; p = 0.049). At latest follow-up, OHS were superior in the PPF after AA-THA group [42.6 (range: 25.0-48.0) vs. 36.6 (range: 21.0-47.0); p = 0.006]. CONCLUSION: Dislocation following PA-THA is more likely to require revision. However, PPF following AA-THA requires more often a different surgical approach and is at higher risk of complications. Despite the increased surgical burden post-operative PROMs are better in the peri-prosthetic fracture group, especially in cases not requiring reoperation. LEVEL OF EVIDENCE: III, case-control study.

Which Acetabular Measurements Most Accurately Differentiate Between Patients and Controls? A Comparative Study.

BACKGROUND: Acetabular morphology is an important determinant of hip biomechanics. To identify features of acetabular morphology that may be associated with the development of hip symptoms while accounting for spinopelvic characteristics, one needs to determine acetabular characteristics in a group of individuals older than 45 years without symptoms or signs of osteoarthritis. Previous studies have used patients with unknown physical status to define morphological thresholds to guide management. QUESTIONS/PURPOSES: (1) To determine acetabular morphological characteristics in males and females between 45 and 60 years old with a high Oxford hip score (OHS) and no signs of osteoarthritis; (2) to compare these characteristics with those of symptomatic hip patients treated with hip arthroscopy or periacetabular osteotomy (PAO) for various kinds of hip pathology (dysplasia, retroversion, and cam femoroacetabular impingement); and (3) to assess which radiographic or CT parameters most accurately differentiate between patients who had symptomatic hips and those who did not, and thus, define thresholds that can guide management. METHODS: Between January 2018 and December 2018, 1358 patients underwent an abdominopelvic CT scan in our institution for nonorthopaedic conditions. Of those, we considered 5% (73) of patients as potentially eligible as controls based on the absence of major hip osteoarthritis, trauma, or deformity. Patients were excluded if their OHS was 43 or less (2% [ 28 ]), if they had a PROMIS less than 50 (1% [ 18 ]), or their Tönnis score was higher than 1 (0.4% [ 6 ]). Another eight patients were excluded because of insufficient datasets. After randomly selecting one side for each control, 40 hips were left for analysis (age 55 ± 5 years; 48% [19 of 40] were in females). In this comparative study, this asymptomatic group was compared with a group of patients treated with hip arthroscopy or PAO. Between January 2013 and December 2020, 221 hips underwent hip preservation surgery. Of those, eight were excluded because of previous pelvic surgery, and 102 because of insufficient CT scans. One side was randomly selected in patients who underwent bilateral procedure, leaving 48% (107 of 221) of hips for analysis (age 31 ± 8 years; 54% [58 of 107] were in females). Detailed radiographic and CT assessments (including segmentation) were performed to determine acetabular (depth, cartilage coverage, subtended angles, anteversion, and inclination) and spinopelvic (pelvic tilt and incidence) parameters. Receiver operating characteristics (ROC) analysis was used to assess diagnostic accuracy and determine which morphological parameters (and their threshold) differentiate most accurately between symptomatic patients and asymptomatic controls. RESULTS: Acetabular morphology in asymptomatic hips was characterized by a mean depth of 22 ± 2 mm, with an articular cartilage surface of 2619 ± 415 mm 2 , covering 70% ± 6% of the articular surface, a mean acetabular inclination of 48° ± 6°, and a minimal difference between anatomical (24° ± 7°) and functional (22° ± 6°) anteversion. Patients with symptomatic hips generally had less acetabular depth (20 ± 4 mm versus 22 ± 2 mm, mean difference 3 mm [95% CI 1 to 4]; p < 0.001). Hips with dysplasia (67% ± 5% versus 70% ± 6%, mean difference 6% [95% CI 0% to 12%]; p = 0.03) or retroversion (67% ± 5% versus 70% ± 6%, mean difference 6% [95% CI 1% to 12%]; p = 0.04) had a slightly lower relative cartilage area compared with asymptomatic hips. There was no difference in acetabular inclination (48° ± 6° versus 47° ± 7°, mean difference 0.5° [95% CI -2° to 3°]; p = 0.35), but asymptomatic hips had higher anatomic anteversion (24° ± 7° versus 19° ± 8°, mean difference 6° [95% CI 3° to 9°]; p < 0.001) and functional anteversion (22° ± 6° versus 13°± 9°, mean difference 9° [95% CI 6° to 12°]; p < 0.001). Subtended angles were higher in asymptomatic at 105° (124° ± 7° versus 114° ± 12°, mean difference 11° [95% CI 3° to 17°]; p < 0.001), 135° (122° ± 9° versus 111° ± 12°, mean difference 10° [95% CI 2° to 15°]; p < 0.001), and 165° (112° ± 9° versus 102° ± 11°, mean difference 10° [95% CI 2° to 14°]; p < 0.001) around the acetabular clockface. Symptomatic hips had a lower pelvic tilt (8° ± 8° versus 11° ± 5°, mean difference 3° [95% CI 1° to 5°]; p = 0.007). The posterior wall index had the highest discriminatory ability of all measured parameters, with a cutoff value of less than 0.9 (area under the curve [AUC] 0.84 [95% CI 0.76 to 0.91]) for a symptomatic acetabulum (sensitivity 72%, specificity 78%). Diagnostically useful parameters on CT scan to differentiate between symptomatic and asymptomatic hips were acetabular depth less than 22 mm (AUC 0.74 [95% CI 0.66 to 0.83]) and functional anteversion less than 19° (AUC 0.79 [95% CI 0.72 to 0.87]). Subtended angles with the highest accuracy to differentiate between symptomatic and asymptomatic hips were those at 105° (AUC 0.76 [95% CI 0.65 to 0.88]), 135° (AUC 0.78 [95% CI 0.70 to 0.86]), and 165° (AUC 0.77 [95% CI 0.69 to 0.85]) of the acetabular clockface. CONCLUSION: An anatomical and functional acetabular anteversion of 24° and 22°, with a pelvic tilt of 10°, increases the acetabular opening and allows for more impingement-free flexion while providing sufficient posterosuperior coverage for loading. Hips with lower anteversion or a larger difference between anatomic and functional anteversion were more likely to be symptomatic. The importance of sufficient posterior coverage was also illustrated by the posterior wall indices and subtended angles at 105°, 135°, and 165° of the acetabular clockface having a high discriminatory ability to differentiate between symptomatic and asymptomatic hips. Future research should confirm whether integrating these parameters when selecting patients for hip preservation procedures can improve postoperative outcomes.Level of Evidence Level III, prognostic study.

Using Unsupervised Machine Learning to Predict Quality of Life After Total Knee Arthroplasty.

BACKGROUND: Patient-reported outcome measures (PROMs) are an important metric to assess total knee arthroplasty (TKA) patients. The purpose of this study was to use a machine learning (ML) algorithm to identify patient features that impact PROMs after TKA. METHODS: Data from 636 TKA patients enrolled in our patient database between 2018 and 2022, were retrospectively reviewed. Their mean age was 68 years (range, 39 to 92), 56.7% women, and mean body mass index of 31.17 (range, 16 to 58). Patient demographics and the Functional Comorbidity Index were collected alongside Patient-Reported Outcome Measures Information System Global Health v1.2 (PROMIS GH-P) physical component scores preoperatively, at 3 months, and 1 year after TKA. An unsupervised ML algorithm (spectral clustering) was used to identify patient features impacting PROMIS GH-P scores at the various time points. RESULTS: The algorithm identified 5 patient clusters that varied by demographics, comorbidities, and pain scores. Each cluster was associated with predictable trends in PROMIS GH-P scores across the time points. Notably, patients who had the worst preoperative PROMIS GH-P scores (cluster 5) had the most improvement after TKA, whereas patients who had higher global health rating preoperatively had more modest improvement (clusters 1, 2, and 3). Two out of Five patient clusters (cluster 4 and 5) showed improvement in PROMIS GH-P scores that met a minimally clinically important difference at 1-year postoperative. CONCLUSIONS: The unsupervised ML algorithm identified patient clusters that had predictable changes in PROMs after TKA. It is a positive step toward providing precision medical care for each of our arthroplasty patients.

The Effect of Surgical Approach and Hip Offset Reconstruction on Gait Biomechanics Following Total Hip Arthroplasty.

BACKGROUND: This study aimed to examine how hip offset (HO) and surgical approach affect gait biomechanics following total hip arthroplasty (THA). METHODS: There were 55 THA patients assigned to 3 groups based on surgical approach (ANT: anterior, LAT: lateral, or POS: posterior) and HO difference (large HO: >5 millimeters (mm), small HO; <5 mm, or normal; between +3 mm and -3 mm). Kinematics and kinetics were recorded using motion capture and force plate data. Group differences were assessed using statistical parametric mapping. RESULTS: The ANT group demonstrated more normal sagittal plane kinematics and kinetics. No frontal plane kinematic differences were found, but the LAT group displayed more normal frontal plane kinetics. The LAT group displayed a slower walking speed than the ANT group, and the LAT and POS groups used a shorter stride/step length than the control group. The large HO group showed fewer differences in sagittal plane kinematics and kinetics than the small HO and normal groups. No frontal plane kinematic differences were observed, but the normal group demonstrated more significant differences than the large HO and small HO groups. No significant differences were found between any of the HO patient groups. CONCLUSION: Anterior and lateral approaches led to more normal gait biomechanics in sagittal kinematics and frontal kinetics, respectively, but only the ANT group exhibited spatiotemporal gait parameters within normal ranges. Hip offset differences greater or less than 5 mm do not significantly change gait patterns. Surgical approach plays a greater role than HO reconstruction in producing more normal gait biomechanics following THA.

Early- to mid-term outcome of a short, cementless, titanium, flat, tapered stem for primary total hip arthroplasty: an independent series.

INTRODUCTION: This study aims to: (1) describe perioperative complications amongst patients who underwent primary total hip arthroplasty (THA) using a short cementless, titanium, flat, tapered stem; (2) estimate this stem's early- to mid-term survival; (3) identify factors associated with revision arthroplasty; and (4) describe femoral remodelling at minimum 6 years postoperatively. METHODS: A retrospective review of consecutive patients who underwent THA using a Taperloc Microplasty stem (Zimmer-Biomet, Warsaw, Indiana, USA) with minimum 2-year follow-up was performed. Surgeries were performed by 1 of 6, non-designer, arthroplasty surgeons between 2014 and 2018. Outcomes included perioperative complications including revision arthroplasty, and survival. Cox analysis was used to analyse the effect of different factors on risk of revision arthroplasty. Radiographs with 6-year follow-up served to describe femoral remodelling. RESULTS: In 1205 patients, followed for 5.1 ± 1.4 years, the incidence of perioperative complication was 5.2% for which 29 patients (2.4%) required revision arthroplasty. The 5- and 7-year survival rates were 97.8% (95% CI, 96.9-98.5) and 97.0% (95% CI, 95.6-98.0), respectively. The only factor associated with revision arthroplasty was proximal femur morphology, as per Dorr classification (HR 1.24 [95%CI, 1.09-1.41]; p = 0.005). During radiographic assessment, 12% of patients showed ⩾25% of relative change in cortical thickness in Gruen zones 3 or 5. We observed calcar remodelling in 50% of radiographs while 10% showed presence of a pedestal sign. CONCLUSIONS: The 7-year survivorship of the Taperloc Microplasty stem is within National Institute for Health and Care Excellence (NICE) guidelines. Patients ⩽65 years with osteoarthritis and Dorr A/B femoral morphology may be ideal candidates for THA with this stem. Femoral remodelling is common and not associated with adverse outcome.

Prevalence of Lumbosacral Transitional Vertebral Anomalies Among Healthy Volunteers and Patients with Hip Pathology: Association with Spinopelvic Characteristics.

A lumbosacral transitional vertebra (LSTV) has been reported to be prevalent among patients with hip dysplasia. The aims of this study were to determine the (1) prevalence of an LSTV in young patients presenting with hip pain and a group of asymptomatic volunteers, (2) effect of an LSTV on spinopelvic characteristics, and (3) presence of low back pain among patients with an LSTV. Methods: This cross-sectional study included 102 patients with hip pathology and 51 asymptomatic volunteers (mean age, 33.9 ± 7.3 years; mean body mass index, 26.0 ± 5.0 kg/m2; 57.5% female). Participants underwent radiographic assessment of the lumbar spine and pelvis in standing and deep-seated positions. LSTV occurrence was classified according to the Castellvi system. Spinopelvic characteristics included lumbar lordosis (including segmental lumbar angles), pelvic tilt, and hip flexion (pelvic-femoral angle). Differences between standing and deep-seated values were calculated. Low back pain was assessed using the Oswestry Disability Index. Results: The prevalence of LSTV type ≥II was 8.5%, with no difference between patients and volunteers (p = 0.386). Individuals with an LSTV had a greater standing L1-L5 angle (mean, 51.6° ± 11.7° versus 38.9° ± 9.3°; p < 0.001). The overall spinal flexion (change in L1-S1 angle between the standing and deep-seated positions) in individuals with an LSTV was similar to that in individuals without an LSTV; restricted L5-S1 mobility was compensated for at L1-L2 (10.2° ± 5.8° in those with versus 8.4° ± 4.1° in those without an LSTV; p = 0.070). No significant difference in the presence of low back pain was found (p = 0.250). Conclusions: An LSTV was found in 8.5% of young adults, with no difference between patients with hip pathology and controls. Individuals with an LSTV have greater standing lumbar lordosis, with altered mechanics at the cephalad adjacent level, which may predispose these individuals to degenerative changes at this level. Level of Evidence: Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.

Patient-clinician digital health interventions for the hip fracture population: a scoping review.

INTRODUCTION: Older adults with hip fracture often require extensive post-surgery care across multiple sectors, making follow-up care even more important to ensure an ideal recovery. With the increased adoption of technology, patient-clinician digital health interventions can potentially improve post-surgery outcomes of hip fracture patients by helping them and their caregivers better understand the various aspects of their care, post-hip fracture surgery. The purpose of this study was to examine the available literature on the impact of hip fracture-specific, patient-clinician digital health interventions on patient outcomes and health care delivery processes. We also aimed to identify the barriers and enablers to the uptake and implementation of these technologies and to provide strategies for improved use of these digital health interventions. METHODS: We conducted a scoping review following the six stages of Arksey and O'Malley's framework and following the PRISMA-ScR reporting format. Searches were conducted in five databases. In addition to hand searching for relevant studies from the references of all included studies, we also conducted a grey literature search to identify relevant primary studies. Screening of titles and abstracts as well as full texts were performed independently by two reviewers. Two reviewers also performed the data extraction of the included studies. RESULTS: After screening 3,638 records, 20 articles met the criteria and 1 article was identified through hand searching. Various patient-clinician digital health interventions were described including telehealth /telerehabilitation programs (n = 6), care transition /follow-up interventions (n = 5), online resources (n = 2), and wearable devices /sensor monitoring (n = 1). Outcomes were varied and included functional status, gait/mobility, quality of life, psychological factors, satisfaction, survival/complications, caregiver outcomes, compliance, technology-user interactions, and feedback on the use of the digital health interventions. For clinicians, a key barrier to the use of the digital health interventions was the acceptability of the technology. However, the usefulness of the digital health intervention by clinicians was seen as both a barrier and an enabler. For patients and caregivers, all the themes were seen as both a barrier and an enabler depending on the study. These themes included: 1) availability and access, 2) usability, 3) knowledge and skills, 4) acceptability, and 5) usefulness of the digital health intervention. CONCLUSION: Many behavioural factors affect the use of patient-clinician digital health interventions. However, a specific attention should be focused on the acceptability of the technology by the clinicians to encourage uptake of the digital health interventions. The results of this scoping review can help to better understand the factors that may be targeted to increase the use of these technologies by clinicians, patients, and caregivers.

Leveraging machine learning and prescriptive analytics to improve operating room throughput.

Successful days are defined as days when four cases were completed before 3:45pm, and overtime hours are defined as time spent after 3:45pm. Based on these definitions and the 460 unsuccessful days isolated from the dataset, 465 hours, 22 minutes, and 30 seconds total overtime hours were calculated. To reduce the increasing wait lists for hip and knee surgeries, we aim to verify whether it is possible to add a 5th surgery, to the typical 4 arthroplasty surgery per day schedule, without adding extra overtime hours and cost at our clinical institution. To predict 5th cases, 301 successful days were isolated and used to fit linear regression models for each individual day. After using the models' predictions, it was determined that increasing performance to a 77% success rate can lead to approximately 35 extra cases per year, while performing optimally at a 100% success rate can translate to 56 extra cases per year at no extra cost. Overall, this shows the extent of resources wasted by overtime costs, and the potential for their use in reducing long wait times. Future work can explore optimal staffing procedures to account for these extra cases.

Outcome of hip resurfacing revision through the Hueter-anterior approach.

BACKGROUND: The Hueter-Anterior Approach (HAA) with its limited soft tissue and internervous dissection has been shown to be an effective approach for primary total hip and hip resurfacing arthroplasty (HRA). The purpose of this study is to evaluate the clinical outcome of patients requiring revision of HRA to total hip replacement using the HAA, assessing function and complications. METHODS: We performed a retrospective review of a prospectively maintained research database. Between 2006 and 2015, 555 primary metal-on-metal (MoM) HRAs were performed via the HAA; we identified 33 hips in 30 patients that required revisions for aseptic causes to THA: aseptic loosening of acetabulum in 12 and femoral in 7, 10 for pseudotumour/ALTR, 4 for femoral neck fracture. All revision surgeries were performed through a HAA by a single surgeon who had also performed the index operation. PROMs were collected preoperatively and yearly at various timepoints postoperatively. RESULTS: The mean age at time of revision was 48.9 years (±5.3 SD) for 22 males (67%) and 11 females (33%). The mean time to revision surgery/failure of hip resurfacing was 3.3 years (±2.4 SD). There were 5 major reoperations with 3 infections, 1 acetabular loosening and 1 trunnionosis. There were significant improvements in multiple PROMs. CONCLUSIONS: The HAA is a viable surgical approach for revision of HRA with smaller initial HRA acetabular components generally requiring a relatively larger acetabular compoent at time of revision. Patients reported improvement in symptoms and function and a lower risk of subsequent reoperation than what has previously been reported for failed MoM bearings.

Acetabular Sector Angles in Asymptomatic and Dysplastic Hips: Defining Dysplasia and Thresholds to Guide Management.

BACKGROUND: Radiographic evaluation plays an important role in detecting and grading hip dysplasia. Acetabular sector angles (ASAs) measure the degree of femoral head coverage provided by the acetabulum on computed tomographic (CT) scans. In this study, we aimed to determine ASA values at different axial levels in a control cohort with asymptomatic, high-functioning hips without underlying hip pathology and a study group with symptomatic, dysplastic hips that underwent periacetabular osteotomy (PAO), thereby defining the ASA thresholds for hip dysplasia. METHODS: This was a cross-sectional study evaluating a control group of 51 patients (102 hips) and a study group of 66 patients (72 hips). The control group was high-functioning and asymptomatic, with an Oxford Hip Score of >43, did not have osteoarthritis (Tönnis grade ≤1), underwent a pelvic CT scan, had a mean age (and standard deviation) of 52.1 ± 5.5 years, and was 52.9% female. The study group had symptomatic hip dysplasia treated with PAO, had a mean age of 29.5 ± 7.3 years, and 83.3% was female. Anterior ASA (AASA) and posterior ASA (PASA) were measured at 3 axial CT levels to determine equatorial, intermediate, and proximal ASA. The thresholds for dysplasia were determined using receiver operating characteristic (ROC) curve analysis, including the area under the curve (AUC). RESULTS: Patients with dysplasia had significantly smaller ASAs compared with the control group; the differences were most pronounced for proximal AASAs and proximal and intermediate PASAs. The control group had a mean proximal PASA of 162° ± 17°, yielding a threshold for dysplasia of 137° (AUC, 0.908). The mean intermediate PASA for the control group was 117° ± 11°, yielding a threshold of 107° (AUC, 0.904). The threshold for anterior dysplasia was 133° for proximal AASA (AUC, 0.859) and 57° for equatorial AASA (AUC, 0.868). The threshold for posterior dysplasia was 102° for intermediate PASA (AUC, 0.933). CONCLUSIONS: Measurement of ASA is a reliable tool to identify focal acetabular deficiency with high accuracy, aiding diagnosis and management. A proximal PASA of <137° or an intermediate PASA of <107° should alert clinicians to the presence of dysplasia. LEVEL OF EVIDENCE: Diagnostic Level III . See Instructions for Authors for a complete description of levels of evidence.

The Impact of Age on Clinical Outcomes of Acetabular Microfracture During FAI Surgery.

BACKGROUND: Full-thickness acetabular cartilage lesions are common findings during primary surgical treatment of femoroacetabular impingement (FAI). PURPOSE: To evaluate clinical outcomes after acetabular microfracture performed during FAI surgery in a prospective, multicenter cohort. STUDY DESIGN: Cohort Study; Level of evidence, 3. METHODS: Patients with FAI who had failed nonoperative management were prospectively enrolled in a multicenter cohort. Preoperative and postoperative (mean follow-up, 4.3 years) patient-reported outcome measures were obtained with a follow-up rate of 81.6% (621/761 hips), including 54 patients who underwent acetabular microfracture. Patient characteristics, radiographic parameters, intraoperative disease severity, and operative procedures were analyzed. Propensity matching using linear regression was used to match 54 hips with microfracture to 162 control hips (1:3) to control for confounding variables. Subanalyses of hips ≤35 and >35 years of age with propensity matching were also performed. RESULTS: Patients who underwent acetabular microfracture were more likely to be male (81.8% vs 40.9%; P < .001), be older in age (35.0 vs 29.9 years; P = .001), have a higher body mass index (27.2 vs 25.0; P = .001), and have a greater alpha angle (69.6° vs 62.3°; P < .001) compared with the nonmicrofracture cohort (n = 533). After propensity matching to control for covariates, patients treated with microfracture displayed no differences in the modified Harris Hip Score or Hip Disability and Osteoarthritis Outcome Score (P = .22-.95) but were more likely to undergo total hip arthroplasty (THA) (13% [7/54] compared with 4% [6/162] in the control group; P = .002), and age >35 years was associated with conversion to THA after microfracture. Microfracture performed at or before 35 years of age portended good outcomes with no significant risk of conversion to THA at the most recent follow-up. CONCLUSION: Microfracture of acetabular cartilage defects appears to be safe and associated with reliably improved short- to mid-term results in younger patients; modified expectations should be realized when full-thickness chondral lesions are identified in patients >35 years of age.

MRI texture analysis of acetabular cancellous bone can discriminate between normal, cam positive, and cam-FAI hips.

OBJECTIVES: To compare the MRI texture profile of acetabular subchondral bone in normal, asymptomatic cam positive, and symptomatic cam-FAI hips and determine the accuracy of a machine learning model for discriminating between the three hip classes. METHODS: A case-control, retrospective study was performed including 68 subjects (19 normal, 26 asymptomatic cam, 23 symptomatic cam-FAI). Acetabular subchondral bone of unilateral hip was contoured on 1.5 T MR images. Nine first-order 3D histogram and 16 s-order texture features were evaluated using specialized texture analysis software. Between-group differences were assessed using Kruskal-Wallis and Mann-Whitney U tests, and differences in proportions compared using chi-square and Fisher's exact tests. Gradient-boosted ensemble methods of decision trees were created and trained to discriminate between the three groups of hips, with percent accuracy calculated. RESULTS: Sixty-eight subjects (median age 32 (28-40), 60 male) were evaluated. Significant differences among all three groups were identified with first-order (4 features, all p ≤ 0.002) and second-order (11 features, all p ≤ 0.002) texture analyses. First-order texture analysis could differentiate between control and cam positive hip groups (4 features, all p ≤ 0.002). Second-order texture analysis could additionally differentiate between asymptomatic cam and symptomatic cam-FAI groups (10 features, all p ≤ 0.02). Machine learning models demonstrated high classification accuracy of 79% (SD 16) for discriminating among all three groups. CONCLUSION: Normal, asymptomatic cam positive, and cam-FAI hips can be discriminated based on their MRI texture profile of subchondral bone using descriptive statistics and machine learning algorithms. CLINICAL RELEVANCE STATEMENT: Texture analysis can be performed on routine MR images of the hip and used to identify early changes in bone architecture, differentiating morphologically abnormal from normal hips, prior to onset of symptoms. KEY POINTS: • MRI texture analysis is a technique for extracting quantitative data from routine MRI images. • MRI texture analysis demonstrates that there are different bone profiles between normal hips and those with femoroacetabular impingement. • Machine learning models can be used in conjunction with MRI texture analysis to accurately differentiate between normal hips and those with femoroacetabular impingement.

Platform-Based Patient-Clinician Digital Health Interventions for Care Transitions: Protocol for a Scoping Review.

BACKGROUND: With the increased adoption of technology, the use of digital health interventions in health care settings has increased. Patient-clinician digital health interventions have the potential to improve patient care, especially during important transitions between hospital and home. Digital health interventions can provide support to patients during these transitions, thereby leading to better patient outcomes. OBJECTIVE: This scoping review aims to explore the available literature, specifically (1) to examine the impact of platform-based digital health interventions focused on care transitions on patient outcomes, and (2) to identify the barriers to and enablers for the uptake and implementation of these digital health interventions. METHODS: This protocol was developed based on Arksey and O'Malley's, Levac and colleagues', and JBI scoping review methodologies, and it has been reported according to the PRISMA-ScR (Preferred Reporting Items for Systematic Reviews and Meta-Analyses Statement for the Scoping Reviews) format. The search strategies were developed for 4 databases: MEDLINE, CINAHL, EMBASE, and the Cochrane Central Register of Controlled Trials by using key words such as "hospital to home transition" and "platform-based digital health." Studies involving patients 16 years or older that used a platform-based digital health intervention during their hospital to home transition will be included in this review. Two reviewers will independently screen articles for eligibility by using a 2-stage process (ie, title and abstract screening and full-text screening). We expect to refine the eligibility criteria during the title and abstract screening process as we anticipate retrieving a significant number of articles. In addition, we will also perform a targeted search of the grey literature, as well as data extraction. Data analysis will consist of a narrative and descriptive synthesis. RESULTS: The review is expected to identify research gaps that will inform the development of future patient-clinician digital health interventions. We have identified a total of 8333 articles. Screening began in September 2022, and data extraction is expected to commence in February 2023 and end by April 2023. Data analyses and final results will be submitted to a peer-reviewed journal in August 2023. CONCLUSIONS: We expect to find a wide variety of postcare interventions, some gaps in the quality of research evidence, as well as a lack of detailed information on digital health interventions. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): PRR1-10.2196/42056.

Impact of Anesthetic Choice on Time to Discharge for Same-Day Discharge Joints.

BACKGROUND: As total joint arthroplasty programs continue to move towards same-day discharge (SDD), time to discharge is an increasingly important performance indicator. The primary objective of this study was to determine the impact of the choice of anesthetic on the time to discharge after SDD primary hip and knee arthroplasty. METHODS: A retrospective chart review was conducted within our SDD arthroplasty program, with 261 patients identified for analysis. Baseline characteristics, length of surgery, anesthetic drug, dose, and perioperative complications were extracted and recorded. The time from the patient leaving the operating room to physiotherapy assessment and from the operating room to discharge were recorded. These were referred to as ambulation time and discharge time, respectively. RESULTS: The ambulation time was significantly reduced when hypobaric lidocaine was used in a spinal block compared to isobaric or hyperbaric bupivacaine-135 minutes (range, 39 to 286), 305 minutes (range, 46 to 591), and 227 minutes (range, 77 to 387), respectively-(P < .0001). Similarly, the discharge time was also significantly lower with hypobaric lidocaine compared to isobaric bupivacaine, hyperbaric bupivacaine, and general anesthesia-276 minutes (range, 179 to 461), 426 minutes (range, 267 to 623), 375 minutes (range, 221 to 511), and 371 minutes (range, 217 to 570), respectively-(P < .0001). No cases of transient neurologic symptoms were reported. CONCLUSION: Patients receiving a hypobaric lidocaine spinal block experienced significantly reduced ambulation time and time to discharge compared to other anesthetics. Surgical teams should feel confident in using hypobaric lidocaine during spinal anesthesia as it is rapid and efficacious.

In meeting the increasing demands for total knee arthroplasty, can we achieve high levels of quality care in a small community hospital? A mixed-methods study.

Purpose: Small community hospitals (SCHs) help meet the demand for total knee arthroplasty (TKA). This mixed-methods study compares outcomes and analyses of environmental differences following TKA at a SCH and a tertiary care hospital (TCH). Methods: Quantitative: A retrospective review of 352 propensity-matched primary TKA procedures at both a SCH and a TCH, based on age, body mass index, and American Society of Anesthesiologists class, was completed. Groups were compared by length of stay (LOS), 90-day emergency department visits, 90-day readmissions, reoperations, and mortality. Qualitative: Based on the Theoretical Domains Framework, seven prospective semistructured interviews were performed. Interview transcripts were coded and belief statements were generated and summarized by two reviewers. Discrepancies were resolved by a third reviewer. Results: Quantitative: The average LOS for the SCH was significantly shorter than that for the TCH (2.0 ± 0.2 vs. 3.6 ± 2.7 days; p < 0.001), a difference that persisted following a subgroup analysis of ASA I/II patients (2.0 ± 0.2 vs. 3.2 ± 2.2; p < 0.001). There were no significant differences in other outcomes. Qualitative: The main themes that revolved around a higher case load for physiotherapy at the TCH resulted in patients waiting longer to be mobilized after surgery. Patient disposition also affected their discharge rates. Conclusion: Given the increasing demand for TKA, the SCH represents a viable option to increase capacity, while reducing LOS. Future directions to reduce LOS include addressing social barriers to discharge and patient prioritization for assessment by allied health services. When TKA is performed by the same set of surgeons, the SCH provides quality care with a shorter LOS and comparable with urban hospitals, and this can be attributed to the differences in resource utilization in the two hospital settings.

Contemporary, non-navigation, cup orientation techniques improve accuracy and eliminate differences seen between the anterior and posterior approach in THA.

BACKGROUND: This study aimed to: (1) Determine the ability to achieve the surgeons' desired cup orientation, without navigation, using contemporary measures with the anterior- (AA) and posterior- approaches (PA); and (2) assess whether surgical approach is associated with cup orientation accuracy, as previously reported, when contemporary measures are used. METHODS: A prospective, 2-centre, multi-surgeon study of 400 THAs (200 AA; 200 PA) was performed. Intraoperative radiographs were obtained with the AA. A digital inclinometer and 3-point pelvic support were used with the PA. With the PA, intraoperative cup inclination at impaction was recorded. Radiographic inclination/anteversion (RI/RA) was measured from intraoperative radiographs (AA-only) and from postoperative radiographs for all cases. Optimum inclination/anteversion was defined as 40°/20° (±10°). The difference between intra- and postoperative orientations allowed for determination of the difference in pelvic position at impaction. RESULTS: Optimum RI and RA were achieved in 91.3% (n = 365) and 92% (n = 368) of cases respectively. Optimum cup orientation was detected in 84% of cases (n = 336). There was equivalent ability to achieve cup orientation between approaches (AA: 82.5% vs. PA: 85.5%; p = 0.41). The use of an inclinometer in the PA was associated with a smaller variability of inclination at implantation (10° vs. 14°) and counteracted the greater difference in pelvic position (4.4° vs. 2.1°) seen with the PA. CONCLUSIONS: Over 80% of cases can have optimum orientation without navigation, using simple, cheap contemporary measures. Such measures eliminate differences between approaches, related to patient position. Narrower implantation angles will further reduce variability in cup orientation achieved.

Use of multidisciplinary positive deviance seminars to improve efficiency in a high-volume arthroplasty practice: a pilot study.

BACKGROUND: Positive deviance (PD) seminars, which have shown excellent results in improving the quality of surgical practices, use individual performance feedback to identify team members who outperform their peers; the strategies from those with exemplary performance are used to improve team members' practices. Our study aimed to use the PD approach with arthroplasty surgeons and nurses to identify multidisciplinary strategies and recommendations to improve operating room (OR) efficiency. METHODS: We recruited 5 surgeons who performed high-volume primary arthroplasty and had participated in 4-joint rooms since 2012, and 29 nurses who had participated in 4-joint rooms and in at least 16 cases in our data set. Three 1-hour PD sessions were held in February and March 2021: 1 with surgeons, 1 with nurses, and 1 with both surgeons and nurses to select recommendations for implementation. The sessions were led by a member of the nonorthopedic surgical faculty who was familiar with the subjects discussed and with PD seminars. To determine the success of the recommendations, we compared OR efficiency before and after implementation. We defined success as performance of 4 joint procedures within 8 hours. RESULTS: Eleven recommendations were recorded from the session with nurses and 7 from the session with surgeons, of which 11 were selected for implementation. During the month after implementation, there were great improvements across all time intervals of surgical procedures, with the greatest improvements seen in mean anesthesia preparation time in the room (4.51 min [26.3%]), mean procedure duration (9.75 min [14.0%]) and mean anesthesia finish time (5.78 min [44.0%]) (all p < 0.001). The total time saved per day was 49.84 minutes; this led to a success rate of 69.0%, a relative increase of 73.8% from our 2012-2020 success rate of 39.7% (p < 0.001). CONCLUSION: The recommendations and increased motivation owing to the individualized feedback reduced time spent per case, allowing more days to finish on time. Positive deviance seminars offer an inexpensive, efficient and collegial means for process improvement in the OR.

Cerclage wire or positional cortical screw for the treatment of intraoperative calcar fractures during primary total hip arthroplasty? A biomechanical study.

BACKGROUND: During primary total hip arthroplasty, intra-operative calcar fractures have been historically treated with cerclage wires. However, interfragmentary screw fixation technique can possibly achieve the same results with technical advantages. The aim of this biomechanical study was to assess stability of calcar fractures fixed using interfragmentary screw technique compared to a traditional cerclage system specifically in context of total hip arthroplasty. METHODS: Thirty-two periprosthetic fractures were reduced using either a single cerclage cable or an intracortical positional screw perpendicular to the fracture line. Axial and torsional load testing was terminated after experimental model failure. FINDINGS: No significant difference was obtained for all output parameters when comparing cerclage wires versus interfragmentary screw fixation respectively. Load at failure: 8043 ± 712 N vs 7425 ± 854 N (p = 0.115). Load at calcar fracture propagation: 6240 ± 2207 N versus 6220 ± 966 N (p = 0.668). Maximum stiffness before failure: 617 ± 115 N/mm vs 839 ± 175 N/mm (p = 0.100) and stiffness at calcar fracture propagation reached 771 ± 153 Nmm vs 886 ± 129 N/mm (p = 0.197). Torque to failure levels obtained were 59.4 ± 7.1 N*m vs 60.9 ± 12.0 N*m (p = 0.908). Torque to calcar fracture propagation, 51.6 ± 6.1 N*m vs 48.5 ± 9.8 N*m (p = 0.298). Torsional stiffness at failure, 0.38 ± 0.03 N*m\deg. vs 0.43 ± 0.13 N*m\deg. (p = 0.465). Torsional stiffness at calcar fracture propagation were 0.37 ± 0.03 N*m\deg. vs 0.45 ± 0.17 N*m\deg. (p = 0.462). INTERPRETATION: The strength of fixation and stability of the implant were similar for both techniques. In the synthetic bone model tested, using an interfragmentary screw conveyed similar stability to the constructs in the management of an intra-operative medial calcar fractures. Thus, potentially giving surgeons an alternative option for intraoperative fracture fixation during primary total hip arthroplasty.

Artificial intelligence-driven prescriptive model to optimize team efficiency in a high-volume primary arthroplasty practice.

PURPOSE: We aimed to improve OR efficiency using machine learning (ML) to find relevant metrics influencing surgery time success and team performance on efficiency to create a model which incorporated team, patient, and surgery-related factors. METHODS: From 2012 to 2020, five surgeons, 44 nurses, and 152 anesthesiologists participated in 1199 four joint days (4796 cases): 1461 THA, 1496 TKA, 652 HR, 242 UKA, and 945 others. Patients were 2461f:2335 m; age, 64.1; BMI, 29.93; and ASA, 2.45. Surgical Success was defined as completing four joints within an eight hour shift using one OR. Time data was recorded prospectively using Surgical Information Management Systems. Hospital records provided team, patient demographics, adverse events, and anesthetic. Data mining identified patterns and relationships in higher dimensions. Predictive analytics used ML ranking algorithm to identify important metrics and created decision tree models for benchmarks and success probability. RESULTS: Five variables predicted success: anaesthesia preparation time, surgical preparation time, time of procedure, anesthesia finish time, and type of joint replacement. The model determined success rate with accuracy of 72% and AUC = 0.72. Probability of success based on mean performance was 77-89% (mean-median) if APT 14-15 minutes, PT 68-70 minutes, AFT four to five minutes, and turnover 25-27 minutes. With the above benchmarks maintained, success rate was 59% if surgeon exceeded 71.5-minutes PT or 89% if 64-minutes procedure time or 66% when anesthesiologist spent 17-19.5 minutes on APT. CONCLUSION: AI-ML predicted OR success without increasing resources. Benchmarks track OR performance, demonstrate effects of strategic changes, guide decisions, and provide teamwork improvement opportunities.