Should We Wait for Bone-on-Bone Arthritis? Equivalent Clinical Outcomes in Patients Requiring Advanced Imaging Before Primary Total Hip Arthroplasty.

BACKGROUND: Plain radiographs remain the standard for diagnosing osteoarthritis (OA). Total hip arthroplasty (THA) is generally offered only for advanced OA by plain radiographs. Advanced imaging is used as an adjunct to assess OA severity in cases of progressive symptoms with less advanced OA by plain radiographs. The objective of this study was to compare outcomes following THA in patients who have advanced OA visualized by plain radiographs to patients who have less severe OA visualized by plain radiographs. METHODS: From February 2016 to February 2020, 93 patients who had Kellgren-Lawrence (KL) grade 0 to 2 OA and underwent THA were identified. The median age was 65 years, and 55% were women. They were matched 1:3 to patients who underwent THA for KL 4 OA based on age, sex, body mass index, and Charlson Comorbidity Index. The primary outcome was achievement of the Hip Injury and Osteoarthritis Outcome Score for Joint Replacement (HOOS JR) minimum clinically important difference, substantial clinical benefit, and patient-acceptable symptom state at 1 year postoperatively. RESULTS: There was no difference between the KL 0 to 2 and KL 4 cohorts in the achievement of HOOS JR minimum clinically important difference (86 versus 85.6%, P = .922), substantial clinical benefit (81.7 versus 80.2%, P = .751), or patient-acceptable symptom state (89.2 versus 85.6%, P = .374). The KL 0 to 2 cohort had a similar improvement in their 2-year HOOS JR (42.5 versus 38.6, P = .019). CONCLUSIONS: In this series, there was no difference in outcomes following primary THA between patients who have severe OA on plain radiographs (KL 4) compared to those who have less severe OA (KL 0 to 2). In the setting of severe symptoms and the absence of advanced OA on radiographs, advanced imaging can be used to guide treatment and select patients who could benefit from THA.

Is Preoperative Weight Reduction in Patients Who Have Body Mass Index ≥ 40 Associated with Lower Complication Rates After Primary Total Hip Arthroplasty?

INTRODUCTION: Given the heightened risk of postoperative complications associated with obesity, delaying total hip arthroplasty (THA) in patients who have a body mass index (BMI) > 40 to maximize pre-operative weight loss has been advocated by professional societies and orthopaedic surgeons. While the benefits of this strategy are not well understood, previous studies have suggested that a 5% reduction in weight or BMI may be associated with reduced complications after THA. METHODS: We identified 613 patients who underwent primary THA in a single institution during a 7-year period, and who had a BMI > 40 recorded 9 to 12 months prior to surgery. Subjects were stratified into three cohorts based on whether their baseline BMI decreased by > 5% (147 patients, 24%), was unchanged (+/-5%) (336 patients, 55%), or increased by > 5% (130 patients, 21%) on the day of surgery. The frequency of 90-day Hip Society and Centers for Medicare & Medicaid Services (CMS) complications was compared between these cohorts. There were significant baseline differences between the cohorts with respect to baseline American Society of Anesthesiologists Class (P < 0.001) and hemoglobin A1C (P = 0.011), which were accounted for in a multivariate regression analysis. RESULTS: In univariate analysis, there was a lower incidence of readmission (P = 0.025) and total complications (P = 0.005) in the increased BMI cohort. The overall complication rate was 18.4% in the decreased BMI cohort, 17.6% in the unchanged cohort, and 6.2% in the increased cohort. However, multivariable regression analysis controlling for potential confounders did not find that preoperative change in BMI was associated with differences in 90-day complications between cohorts (P > 0.05). CONCLUSION: Patients who have a BMI > 40 and achieved a clinically significant (> 5%) BMI reduction prior to THA did not have a lower risk of 90-day complications or readmissions. Thus, delaying THA in these patients to encourage weight loss may result in restricting access to a beneficial surgery without an appreciable safety benefit.

Substantial Weight Loss May Not Improve Early Outcomes of Total Knee Arthroplasty in the Morbidly Obese.

BACKGROUND: Body mass index (BMI) cutoffs for morbidly obese patients otherwise indicated for total knee arthroplasty (TKA) have been widely proposed and implemented, though they remain controversial. Previous studies suggested that a 5% reduction in BMI may be associated with fewer postoperative complications. Thus, the purpose of this study was to determine whether a substantial reduction in preoperative BMI in morbidly obese patients improved 90-day outcomes after TKA. METHODS: There were 1,270 patients who underwent primary TKA at a single institution and had a BMI > 40 recorded during the year prior to surgery. Patients were stratified into three cohorts based on whether their BMI within 3 months to 1 year preoperatively had decreased by ≥ 5% (228 patients [18%]); increased by ≥ 5% (310 [24%]); or remained unchanged (within 5%) (732 [58%]) on the day of surgery. There were several baseline differences between the cohorts with respect to medical comorbidities. The rate of 90-day complications and six-week patient-reported outcome measures were compared via univariate and multivariable analyses. RESULTS: On univariate analysis, individual and total complication rates were similar between the cohorts (P > .05). On multivariable logistic regression, the risk of complications was similar in patients who had decreased versus unchanged BMI (OR [odds ratio] 1.0; P = .898). However, there was a higher risk of complications in the increased BMI cohort compared to those patients who had an unchanged BMI (OR 1.5; P = .039). The six-week patient-reported outcome measures were similar between the cohorts. CONCLUSIONS: Patients who have a BMI > 40 who achieved a meaningful reduction in BMI prior to TKA did not have a lower rate of 90-day complications than those whose BMI remained unchanged. Furthermore, considering that nearly one in four patients experienced a significant increase in BMI while awaiting surgery, postponing TKA may actually be detrimental.

Suction adhesion in the gliding joint of a cephalopod.

We have discovered features of the nuchal joint in the squid, Doryteuthispealeii, that are unique compared with moveable joints in other animals. The joint's function is unclear but it allows the head to glide toward and away from the mantle. The head glides along the joint with ease yet disarticulating the joint perpendicular to the axis of movement requires considerable force. After disarticulation, the joint components can be repositioned and full function restored immediately. Thus, an unknown attachment mechanism prevents the joint from being disarticulated yet permits gliding. We show that the joint was formed by the articulation of the nuchal cartilage and a heretofore-undescribed organ that we named the nuchal 'joint pad'. The joint pad is composed predominantly of muscle, connective tissue and cartilage organized into two distinct regions: a ventral cartilaginous layer and a dorsal muscular layer. Disarticulating the nuchal joint at a displacement rate of 5 mm s-1 required 1.5 times greater stress (i.e. force per unit area) than at 1 mm s-1 The force required to disarticulate the joint increased with nuchal cartilage area0.91 and with nuchal cartilage length1.88 The stress required to shear the nuchal joint was nearly three orders of magnitude lower than that required to disarticulate the joint. Stimulation of the joint pad dorso-ventral musculature resulted in significantly greater shear force required to move the joint (P=0.004). Perforating the nuchal cartilage decreased the stress required to disarticulate the joint to nearly zero. The results support the hypothesis that suction is the attachment mechanism.

Does Early Proximal Femoral Varus Osteotomy Shorten the Duration of Fragmentation in Perthes Disease? Lessons From a Prospective Multicenter Cohort.

BACKGROUND: The prognosis of Legg-Calvé-Perthes disease (LCPD) is dependent upon several factors, with the length and severity of the fragmentation stage among the most important. Previous retrospectively collected data from a single center have suggested that early proximal femoral varus osteotomy (PFO) may shorten the length of fragmentation and allow 34% of patients to bypass fragmentation altogether resulting in less femoral head deformity. The purpose of this study was to validate these findings in a prospectively collected multicenter cohort. METHODS: Patients with LCPD treated with early PFO (during Waldenström stage I) were prospectively followed with serial radiographs at 3-month intervals until a minimum of 2-year follow-up. Waldenström stages and lateral pillar class were determined by mode assessments from 3 pediatric orthopaedic surgeons. The duration of fragmentation was defined as the interval between the first radiographs demonstrating features of stage IIa and stage IIIa. "Complete" bypass was defined as the absence of stage IIa or IIb findings on sequential radiographs with no development of femoral head deformity or collapse. "Partial" bypass was defined as the absence of advanced features of fragmentation and femoral head collapse (stage IIb). RESULTS: Forty-six patients (80% male individuals) with initial stage LCPD and a mean age of 8.2±1.2 years were identified. The weighted kappa statistics for Waldenström staging and lateral pillar classifications showed excellent (0.833) and substantial (0.707) agreement, respectively. Ninety-eight percent of patients (45/46) underwent some period of fragmentation lasting between 91 and 518 days; the median duration was 206 days (interquartile range, 181 to 280). One patient (2%) bypassed fragmentation completely; 8 patients (17%) demonstrated partial bypass. Patients who completely or partially bypassed fragmentation experienced significantly less severe lateral pillar collapse (P=0.016) and shorter fragmentation duration (P=0.001). CONCLUSIONS: In this prospective multicenter cohort, we found a lower rate of fragmentation bypass than previously reported. Nonetheless, our data support the previous contention that early PFO may shorten fragmentation and minimize collapse in LCPD compared with historical controls. Further study with larger cohorts and a more rigorous definition of what constitutes bypass is warranted to clarify the effect of early PFO on the reparative biology of LCPD. LEVEL OF EVIDENCE: Level IV-therapeutic study.

Prolonged Postoperative Intubation After Spinal Fusion in Cerebral Palsy: Are There Modifiable Risk Factors and Associated Consequences?

BACKGROUND: Instrumented spinal fusion is performed to correct severe spinal deformity that commonly complicates cerebral palsy (CP). Prolonged intubation (PI) is a common perioperative complication, though little is known about the risk factors and consequences of this phenomenon. QUESTIONS/PURPOSES: The purpose of this study was to determine (1) the preoperative and intraoperative risk factors associated with PI after spine surgery for CP; (2) the perioperative and postoperative complications associated with PI; and (3) any long-term impacts of PI with respect to health-related quality of life. PATIENTS AND METHODS: A retrospective case-control analysis of prospectively collected, multicenter data was performed on patients with Gross Motor Function Classification System (GMFCS) 4 or 5 CP who underwent instrumented spinal fusion. Patients extubated on postoperative day (POD) 0 were in the early extubation (EE) cohort and those extubated on POD 3 or later were in the PI cohort. Comparisons were made between PI and EE groups with respect to several preoperative and intraoperative variables to identify risk factors for PI. Multivariate logistic regression was performed to identify independent predictors of this outcome. The postoperative hospital course, rate of complications, and health-related quality of life at 2 years were also compared. RESULTS: This study included 217 patients (52% male individuals; mean age, 14.0±2.8 y) who underwent spinal fusion for CP. In this cohort, 52 patients (24%) had EE and 58 patients (27%) had PI. There were several independent predictors of PI including history of pneumonia [odds ratio (OR), 6.2; 95% confidence interval (CI), 1.6-24.3; P=0.01], estimated blood loss of >3000 mL (OR, 16.5; 95% CI, 2.0-134; P=0.01), weight of <37 kg (OR, 6.4; 95% CI, 1.5-27.1), and Child Health Index of Life with Disabilities (CPCHILD) Communication and Social Interaction score of <15 (OR, 10.8; 95% CI, 1.1-107.3; P=0.04). In addition, PI was associated with a higher rate of perioperative and postoperative respiratory (P<0.001), cardiovascular (P=0.014), gastrointestinal (P<0.001), and surgical site (0.027) complications, in addition to prolonged hospitalization (P<0.001) and intensive care unit stay (P<0.001). CONCLUSIONS: Surgeons should seek to optimize nutritional status and pulmonary function, and minimize blood loss in patients with CP to decrease the risk of PI after spinal fusion. Efforts should be made to extubate patients on POD 0 to decrease the risk of complications associated with PI.

Robotics and Navigation Do Not Affect the Risk of Periprosthetic Joint Infection Following Primary Total Hip Arthroplasty: A Propensity Score-Matched Cohort Analysis.

BACKGROUND: The use of computer navigation or robotic assistance during primary total hip arthroplasty (THA) has yielded numerous benefits due to more accurate component positioning. The utilization of these tools is generally associated with longer operative times and also necessitates additional surgical equipment and personnel in the operating room. Thus, the aim of this study was to evaluate the impact of technology assistance on periprosthetic joint infection (PJI) after primary THA. METHODS: We retrospectively reviewed the records for 12,726 patients who had undergone primary THA at a single high-volume institution between 2018 and 2021. Patients were stratified by surgical technique (conventional THA, computer-navigated THA [CN-THA], or robotic-assisted THA [RA-THA]) and were matched 1:1 with use of propensity score matching. Univariate and logistic regression analyses were performed to compare the rates of PJI within 90 days postoperatively between the cohorts. RESULTS: After propensity score matching, there were 4,006 patients in the THA versus RA-THA analysis (2,003 in each group) and 5,288 patients in the THA versus CN-THA analysis (2,644 in each group). CN-THA (p < 0.001) and RA-THA (p < 0.001) were associated with longer operative times compared with conventional THA by 3 and 11 minutes, respectively. The rates of PJI after conventional THA (0.2% to 0.4%) were similar to those after CN-THA (0.4%) and RA-THA (0.4%). On the basis of logistic regression, the development of PJI was not associated with the use of computer navigation (odds ratio [OR], 1.8 [95% confidence interval (CI), 0.7 to 5.3]; p = 0.232) or robotic assistance (OR, 0.9 [95% CI, 0.3 to 2.3]; p = 0.808). CONCLUSIONS: Despite longer operative times associated with the use of computer navigation and robotic assistance, the use of these tools was not associated with an increased risk of PJI within 90 days after surgery. LEVEL OF EVIDENCE: Therapeutic Level III . See Instructions for Authors for a complete description of levels of evidence.

Clinical outcomes and return to dance after total hip arthroplasty or hip resurfacing in professional dancers.

Aims: Professional dancers represent a unique patient population in the setting of hip arthroplasty, given the high degree of hip strength and mobility required by their profession. We sought to determine the clinical outcomes and ability to return to professional dance after total hip arthroplasty (THA) or hip resurfacing arthroplasty (HRA). Methods: Active professional dancers who underwent primary THA or HRA at a single institution with minimum one-year follow-up were included in the study. Primary outcomes included the rate of return to professional dance, three patient-reported outcome measures (PROMs) (modified Harris Hip Score (mHHS), Hip disability and Osteoarthritis Outcome Score for Joint Replacement (HOOS-JR), and Lower Extremity Activity Scale (LEAS)), and postoperative complications. Results: A total of 49 hips in 39 patients (mean age 56 years (SD 13); 80% female (n = 39)) were included. Mean follow-up was 4.9 years (SD 5.1). Of these 49 hips, 37 THAs and 12 HRAs were performed. In all, 96% of hips returned to professional dance activities postoperatively. With regard to PROMs, there were statistically significant improvements in mHHS, HOOS-JR, and LEAS from baseline to ≥ one year postoperatively. There were complications in 7/49 hips postoperatively (14%), five of which required revision surgery (10%). There were no revisions for instability after the index procedure. Two complications (5.4%) occurred in hips that underwent THA compared with five (42%) after HRA (p = 0.007), though the difference by procedure was not significantly different when including only contemporary implant designs (p = 0.334). Conclusion: Active professional dancers experienced significant improvements in functional outcome scores after THA or HRA, with a 96% rate of return to professional dance. However, the revision rate at short- to mid-term follow-up highlights the challenges of performing hip arthroplasty in this demanding patient population. Further investigation is required to determine the results of THA versus HRA using contemporary implant designs in these patients.

Short-Term Outcomes of Concomitant Patellofemoral Arthroplasty and Medial Patellofemoral Ligament Reconstruction to Treat Concurrent Patellofemoral Arthritis and Patellar Instability.

The purpose of this study was to evaluate the efficacy of combined patellofemoral arthroplasty (PFA) and medial patellofemoral ligament (MPFL) reconstruction in patients with patellofemoral arthritis in the setting of concomitant patellar instability. Patients who underwent single-stage, combined PFA and MPFL reconstruction by a single surgeon at a tertiary-care orthopaedic center between 2016 and 2021 were identified. Postoperative radiographic and clinical outcomes at a minimum of 6 months were recorded using patient-reported outcome measures, including International Knee Documentation Committee (IKDC), Kujala, and VR-12. Early complications and rates of recurrent instability were also recorded. Of the 16 patients who met inclusion and exclusion criteria, 13 patients were available for final follow-up (81%; 51.7 ± 7.2 years, 11 females, 2 males) with a mean clinical follow-up of 1.3 ± 0.5 years (range: 0.5-2.3 years). Patients experienced significant improvements in patellar tilt and multiple patient-reported outcome metrics postoperatively, including IKDC, Kujala, VR-12 Mental Health, and VR-12 Physical Health. At the time of the most recent follow-up, no patient had experienced a postoperative dislocation or subluxation event. The findings suggest that concurrent PFA and MPFL reconstruction are associated with significant improvements in multiple patient-reported outcomes. Further studies are needed to evaluate the duration of clinical benefits achieved with this combined intervention.

Telemedicine in Arthroplasty Patients: Which Factors Are Associated With High Satisfaction?

Background: During the initial coronavirus pandemic lockdown period, remote hip and knee arthroplasty care was heavily employed out of necessity. However, data on patient satisfaction with telemedicine specific to hip and knee arthroplasty patients remains unknown. Methods: All patients who had a telemedicine visit in the hip and knee arthroplasty department and completed a telemedicine satisfaction survey at a specialty hospital from April 1, 2020, to December 31, 2020, were identified. Patient satisfaction with telemedicine, gauged through a series of questions, were analyzed and evaluated over time. Independent factors associated with high satisfaction, defined as the "Top Box" response to the survey question "Likelihood of your recommending our video visit service to others," were identified. Results: Overall, 29,003 patients who had an in-person or telemedicine visit in the hip and knee arthroplasty department during the study period were identified. During the initial coronavirus pandemic lockdown period, defined as April 1, 2020-May 31, 2020, rate of overall telemedicine utilization was approximately 84%. After the initial lockdown period, the rate of overall telemedicine utilization was approximately 8% of all visits per month. Average satisfaction scores for a series of 14 questions were consistently above 4.5 out of 5. Multivariable regression revealed younger age, particularly 18-64 years old, to be the only independent factor associated with high satisfaction with telemedicine. The rate of high satisfaction remained statistically similar throughout the study period (P > .05). Conclusions: Patient satisfaction with telemedicine was consistently high in various domains and remained high throughout the study period, regardless of loosened pandemic restrictions. This technology will most likely continue to be utilized, but perhaps it should be targeted at patients younger than 65 years of age.

A multicentre prospective assessment of the utility of robotic assisted total hip arthroplasty with virtual range of motion on intraoperative implant positioning.

BACKGROUND: The growing adoption of robotic-assistance during total hip arthroplasty (THA) has provided novel means through which a patient's anatomy and dynamic spinopelvic relationship can be incorporated into surgical planning. However, the impact of enhanced technologies on intraoperative decision-making and changes to component positioning has not yet been described. METHODS: A multicentre, prospective study included 105 patients (52% women) patients who underwent robotic-assisted THA with the integration of software that incorporates a patient's pelvic tilt (PT) and virtual range-of-motion (VROM) for impingement modeling. The primary outcome of the study was the percentage of patients who underwent changes to the preoperative plan for cup position after incorporating the data from the software. RESULTS: Utilising the intraoperative VROM information, the preoperative plan for cup position was changed from the default (40° inclination and 20° anteversion) in 82/105 (78%) cases. When stratifying by spinopelvic mobility, 64% were considered normal (change ⩾ 10° and ⩽30°), 27% were stiff (change < 10°), and 9% were hypermobile (change > 30°). For all cohorts, the majority of cases (78%) deviated from the 40° inclination and 20° version target. When evaluating the proportion of cases within the Lewinnek and Callanan safe zones based on spinopelvic mobility, 19% of cases within the normal group were planned outside of both zones compared to 39% of stiff cases and 10% of hypermobile cases. CONCLUSIONS: Utilising the latest version of robotic-assisted THA software, the preoperative plan for cup position was changed in the vast majority (78%) of patients, causing substantial deviations from traditional, generic cup targets.

Frequency and Timing of Postoperative Complications After Outpatient Total Hip Arthroplasty.

Background: Although there have been several studies describing risk factors for complications after outpatient total hip arthroplasty (THA), data describing the timing of such complications is lacking. Methods: Patients who underwent outpatient or inpatient primary THA were identified in the 2012-2019 National Surgical Quality Improvement Program database. For 9 different 30-day complications, the median postoperative day of diagnosis was determined. Multivariable regressions were used to compare the risk of each complication between outpatient vs inpatient groups. Multivariable Cox proportional hazards modeling was used to evaluate the differences in the timing of each adverse event between the groups. Results: After outpatient THA, the median day of diagnosis for readmission was 12.5 (interquartile range 5-22), surgical site infection 15 (2-21), urinary tract infection 13.5 (6-19.5), deep vein thrombosis 13 (8-21), myocardial infarction 4.5 (1-7), pulmonary embolism 15 (8-25), sepsis 16 (9-26), stroke 2 (0-7), and pneumonia 6.5 (3-10). On multivariable regressions, outpatients had a lower relative risk (RR) of readmission (RR = 0.73), surgical site infection (RR = 0.72), and pneumonia (RR = 0.1), all P < .05. On multivariable cox proportional hazards modeling, there were no statistically significant differences in the timing of each complication between outpatient vs inpatient procedures (P > .05). Conclusions: The timing of complications after outpatient THA was similar to inpatient procedures. Consideration should be given to lowering thresholds for diagnostic testing after outpatient THA for each complication during the at-risk time periods identified here. Although extremely rare, this is especially important for catastrophic adverse events, which tend to occur early after discharge.

Who gets staged surgery in severe pediatric and adolescent spine deformity?

BACKGROUND: There is significant debate regarding the indications of staged surgery for severe adolescent spinal deformity, and the factors associated with the decision to perform staged compared to same-day surgery have not been previously investigated. Thus, the purpose of this study was to determine which factors were most strongly associated with this decision. METHODS: A prospective multicenter registry of adolescent patients with severe spinal deformity was reviewed. Two cohorts were identified: those who underwent a planned staged surgical procedure for deformity correction and those who underwent a same-day procedure. Patients who underwent an unplanned staged procedure secondary to complications during the initial procedure were excluded. Comparisons were made between these cohorts with respect to preoperative patient and radiographic variables to determine which factors were associated with the decision to perform a staged procedure. Surgical data was also compared to evaluate for differences in the intraoperative management of staged versus same-day patients. RESULTS: Two hundred and twenty-nine patients with severe spinal deformities were identified. Forty patients (17%) underwent a planned staged procedure and 189 patients (80%) underwent a same-day procedure. On univariate analysis of preoperative variables, patients who underwent staged surgery had a significantly younger age at surgery, greater major curve magnitude, greater major curve AVT to CSVL, lesser thoracic spine height, greater radiographic trunk shift, and a greater proportion of patients undergoing revision surgery (as opposed to primary correction) compared to those who underwent a planned single-stage procedure. Multivariate logistic regression of pre-operative variables showed that age < 16 years, maximum cobb angle ≥ 120 degrees, major curve AVT to CSVL of ≥ 3.5 cm, and revision surgery were independently associated with the decision to perform a staged procedure. Intraoperatively, patients in the staged cohort more frequently underwent combined anterior and posterior procedures, grade 4 or higher Schwab osteotomies, and had a greater number of levels fused. CONCLUSION: There is substantial variability with respect to the decision to perform surgery for severe adolescent spine deformities in a staged versus same-day fashion. This large analysis of prospectively collected data is the first to describe the factors most strongly associated with the decision to perform a staged procedure and may help guide the surgical decision-making for these patients.

Distal Tibia Apex Posterior Angulation: A Normal Anatomic Variant Related to Hindfoot Alignment With Side-to-Side Symmetry.

OBJECTIVES: The sagittal plane of the distal tibia has not been well-described. This study sought to characterize sagittal plane morphology, determine symmetry from side to side, and identify differences based on hindfoot alignment. METHODS: One hundred twelve bilateral lateral weight-bearing ankle radiographs were retrospectively evaluated (224 ankles). Hindfoot alignment was classified as neutral, planus, or cavus using the Meary angle. The angle between the diaphyseal and distal tibia axes was measured, and the apex location relative to the plafond was recorded. RESULTS: A mean distal tibia apex posterior angulation (DTAPA) of 2.0° (range -2° to 7°, SD = 2.06°) was located 8.0 cm proximal to the plafond. No difference was observed from side to side in DTAPA magnitude (P = 0.36) or location (P = 0.90). Planus alignment was associated with a significantly greater DTAPA (3.05°) as compared with neutral (1.89°) (P = 0.002) and cavus (1.25°) (P < 0.001) alignment. CONCLUSION: The distal tibia has an apex posterior angulation, suggesting that the true anatomic axis of the tibia terminates just posterior to the plafond center. Hindfoot alignment is related to distal tibia morphology. DTAPA symmetry indicates that contralateral imaging can be used to guide reconstruction of patient-specific anatomy and alignment. Knowledge of the DTAPA may help mitigate sagittal malalignment during distal tibia fracture surgery.

No Effect of Surgical Approach on Discharge Outcomes in Outpatient Total Hip Arthroplasty.

Background: The interest in ambulatory total hip arthroplasty (THA) has increased recently due to a national focus on value-based care and improved rapid recovery protocols. Purpose: We sought to determine if surgical approach had an effect on discharge outcomes in outpatient THA. Methods: We performed a retrospective cohort study examining patients who underwent unilateral THA at a single institution using a standardized perioperative care pathway who were discharged home within 24 hours. In total, we compared 106 patients who underwent THA using the direct anterior approach (ATHA) and 90 patients who underwent THA using the posterior approach (PTHA). Univariate and multivariable analyses were used to compare time to ambulation, length of surgery, readmissions, and 90-day complications. Results:Time to ambulation in the ATHA and PTHA groups was 3.9 hours and 4.1 hours, respectively, and time to discharge was 5.9 hours and 6.0 hours, respectively. Length of surgery was shorter in the ATHA group than in the PTHA group (78 minutes vs 86 minutes, respectively). Complications occurred in 3 patients (3%) in the ATHA group vs 4 patients (4%) in PTHA group. In both groups, early ambulation (within 5 hours) predicted earlier time to discharge. Surgical approach was not associated with time to ambulation or time to discharge on multivariable analysis. Conclusion: In this retrospective study, outpatient THA was feasible in a well-selected population of patients undergoing anterior or posterior approaches. Further study is warranted.

Risk factors for persistent coronal imbalance or revision surgery following L3 LIV selection in adolescent idiopathic scoliosis (AIS).

STUDY DESIGN: Retrospective case-control. OBJECTIVE: To identify a cohort of patients with persistent coronal imbalance (CIB) or revision surgery 5 years following fusion to an L3 lowest-instrumented-vertebra (LIV) and determine factors that make an L3 LIV high-risk. In surgical planning for AIS, L3 is chosen over L4 whenever possible to maximize motion segments below the LIV. Though fusion to an L3 LIV is common, the rate of failure and its risk factors have not been described. METHODS: In this analysis of prospectively-collected multi-center data of AIS patients who underwent posterior spinal fusion (PSF) to an L3 LIV, we identified patients with CIB at 5 years and/or those who required revision surgery attributable to LIV selection. Patients who were balanced at 5 years and did not require revision surgery served as controls. Pre-operative patient and radiographic variables were compared between cases and controls to identify risk factors for CIB/revision surgery. RESULTS: We identified 646 patients with 2-year follow-up and 225 patients with 5-year follow-up, of which 11 were found to have CIB and/or revision surgery attributable to selecting L3 as the LIV. There were statistically significant differences between cases and controls with respect to several pre-operative factors, including BMI (24.5 in cases vs. 20.1 in controls; p = 0.01), Lenke curve type (81.8% Lenke 5/6 vs. 44.4%; p = 0.03), lumbar curve magnitude (56 vs. 45°; p < 0.01), TL/L apical vertebral translation (AVT) (6.2 vs. 4.1 cm; p < 0.01), L3 angulation (30° vs. 22°; p < 0.01), L3 translation (4.3 vs. 2.9 cm; p < 0.01), thoracic rib hump (7° vs. 12°; p = 0.02), lumbar rib hump (16° vs. 10°; p < 0.01), and thoracolumbar (T10-L2) kyphosis (10.5° vs. 2°; p = 0.006). Multivariate logistic regression showed that pre-operative BMI, TL/L AVT, L3 angulation, L3 translation, lumbar rib hump, and thoracolumbar kyphosis were independent predictors of CIB/revision surgery. CONCLUSIONS: An L3 LIV is frequently successful at 5 years post-operatively. Consider an L4 LIV when: pre-operative BMI ≥ 28, L3 angulation ≥ 25°, L3 translation ≥ 4 cm, TL/L AVT ≥ 6 cm, or the lumbar curve is large (≥ 55°) and rotated (≥ 10°). LEVEL OF EVIDENCE: Level III.

Are Junior Residents Competent at Closed Reduction and Casting of Distal Radius Fractures in Children?

BACKGROUND: At many institutions, junior orthopaedic surgery residents perform the closed reduction and casting of pediatric distal radius fractures (DRFs). The purpose of this study was to evaluate the competency of junior residents compared to senior residents in the initial management of pediatric DRFs. METHODS: This investigation was a case-control study analyzing the outcomes of children with displaced DRFs treated by junior versus senior residents. The cohorts were matched with respect to fracture type. Radiographs were measured to assess fracture angulation, displacement, and cast index. Comparisons of patient characteristics, fracture characteristics, and outcome variables were made between the cohorts. RESULTS: A total of 132 patients (99 males; mean age 10.7±2.6 years) were included. Junior residents achieved a similar rate of acceptable initial reduction compared to senior residents (82% versus 79%; p=0.66). Twenty-four (23%) patients were found to have loss of reduction (LOR), though the rate of LOR was similar in the junior (16.7%) and senior resident (28.9%) cohorts (p=0.13). Overall, only 6 patients (3.7%) required surgery (1.5% in junior versus 7.6% in senior; p=0.09). The odds of LOR were 2.7 times higher in the first three reductions of the rotation for all residents (p=0.049). CONCLUSION: Junior residents perform similarly to senior residents in the closed reduction and casting of pediatric DRFs. However, residents performing one of their first three closed reductions during a rotation-regardless of seniority-were more likely to experience subsequent loss of reduction, suggesting the need for close supervision during the beginning of each rotation.Level of Evidence: III.

A Novel Shorthand Approach to Knee Bone Age Using MRI: A Validation and Reliability Study.

BACKGROUND: Bone-age determination remains a difficult process. An atlas for bone age has been created from knee-ossification patterns on magnetic resonance imaging (MRI), thereby avoiding the need for radiographs and associated costs, radiation exposure, and clinical inefficiency. Shorthand methods for bone age can be less time-consuming and require less extensive training as compared with conventional methods. PURPOSE: To create and validate a novel shorthand algorithm for bone age based on knee MRIs that could correlate with conventional hand bone age and demonstrate reliability across medical trainees. STUDY DESIGN: Cohort study (diagnosis); Level of evidence, 2. METHODS: Included in this study were adolescent patients who underwent both knee MRI and hand bone age radiographs within 90 days between 2009 and 2018. A stepwise algorithm for predicting bone age using knee MRI was developed separately for male and female patients, and 7 raters at varying levels of training used the algorithm to determine the bone age for each MRI. The shorthand algorithm was validated using Spearman rho (r S) to correlate each rater's predicted MRI bone age with the recorded Greulich and Pyle (G&P) hand bone age. Interrater and intrarater reliability were also calculated using intraclass correlation coefficients (ICCs). RESULTS: A total of 38 patients (44.7% female) underwent imaging at a mean age of 12.8 years (range, 9.3-15.7 years). Shorthand knee MRI bone age scores were strongly correlated with G&P hand bone age (r S = 0.83; P < .001). The shorthand algorithm was a valid predictor of G&P hand bone age regardless of level of training, as medical students (r S = 0.75), residents (r S = 0.81), and attending physicians (r S = 0.84) performed similarly. The interrater reliability of our shorthand algorithm was 0.81 (95% CI, 0.73-0.88), indicating good to excellent interobserver agreement. Respondents also demonstrated consistency, with 6 of 7 raters demonstrating excellent intrarater reliability (median ICC, 0.86 [range, 0.68-0.96]). CONCLUSION: This shorthand algorithm is a consistent, reliable, and valid way to determine skeletal maturity using knee MRI in patients aged 9 to 16 years and can be utilized across different levels of orthopaedic and radiographic expertise. This method is readily applicable in a clinical setting and may reduce the need for routine hand bone age radiographs.

Risk Factors for Failed Closed Reduction of Pediatric Distal Radius Fractures.

Purpose: Distal radius fractures (DRFs) are common pediatric injuries typically treated with closed reduction and casting. A substantial number of these fractures fail nonsurgical management, occasionally requiring surgical intervention. Risk factors associated with an unsuccessful initial closed reduction (UIR) attempt or loss of reduction (LOR) after a successful closed reduction remain poorly characterized. Methods: This was a retrospective investigation of pediatric patients with displaced DRFs treated by closed reduction and casting at a single children's hospital from 2013 to 2017. Patient factors (age, sex, and body mass index) and radiographic measurements (fracture type, fracture displacement, associated ulna fracture, and cast index) were evaluated to determine risk factors for UIR and LOR. Results: We identified 159 children (118 boys, mean age, 11 ± 3 years) with DRFs who underwent closed reduction and casting. An initial acceptable reduction was achieved in 81% of patients, and LOR occurred in 21.7%. Higher initial fracture translation in the sagittal or coronal plane and higher initial angulation in the coronal plane were associated with higher fluoroscopy times. Higher initial translation in the sagittal plane was independently associated with UIR. After closed reduction, residual translation in the sagittal plane and cast index were independent predictors for LOR. Fractures that were completely displaced in the sagittal plane were 6.2 times less likely to undergo an acceptable initial reduction, and fractures with any residual postreduction translation in the sagittal plane were 4.7 times more likely to demonstrate LOR. Conclusions: The most important factors predicting failure of nonsurgical management of pediatric DRFs are translation in the sagittal plane and cast index greater than 0.80. To optimize patient outcomes, these variables should be recognized by the treating provider and emphasized during simulation training of orthopedic and plastic surgery residents. Type of study/level of evidence: Prognostic III.

Severe persistent coronal imbalance following instrumented posterior spinal fusion for adolescent idiopathic scoliosis.

STUDY DESIGN: Retrospective case-control study. OBJECTIVE: The aim of this study was to identify the risk factors and health-related quality of life (HRQoL) impact of severe (> 4 cm) post-operative coronal imbalance at 2 years following posterior spinal fusion (PSF) for adolescent idiopathic scoliosis (AIS). Coronal imbalance is an unfavorable outcome following PSF for AIS, though the degree of imbalance in such patients is typically mild. We hypothesize that a small number of patients become and remain severely imbalanced post-operatively, though this phenomenon has not been well studied. METHODS: Prospectively collected data from a large multicenter registry were reviewed. Patients with severe coronal imbalance (SCIB; > 4 cm) 2 years after PSF were included. Matched controls without SCIB at 2 years were included at a 3:1 ratio. Comparisons were made between demographics, pre-operative radiographic measures, surgical factors, residual post-operative radiographic measures, and 2-year SRS-22 scores. RESULTS: Nine of 954 (0.9%) patients (88.9% females; mean age 14.8 ± 2.3 years) were found to be severely imbalanced at 2 years. These patients had significantly greater pre-operative bending thoracic curve magnitude (45° vs. 33°; p = 0.013), curve flexibility (22.9% vs. 63.3%; p = 0.004), and kyphosis (41° vs. 26.5°; p = 0.034) compared to matched controls. Pre-operative curve flexibility of < 20% was associated with a 23.8 times greater odds of SCIB (95% CI 2.1-250; p = 0.008). With respect to HRQoL, median SRS-22 pain (4.1 vs. 4.8; p = 0.041), self-image (3.9 vs. 4.6; p = 0.013), general function (4.5 vs. 5; p = 0.022), and total (4.1 vs. 4.7; p = 0.012) scores at 2 years were significantly lower in cases compared to controls. CONCLUSIONS: In the present study, thoracic curve stiffness was a strong risk factor for severe post-operative coronal imbalance, which was associated with poor HRQoL measures. Increased pre-operative thoracic curve stiffness (< 20% flexibility) should raise surgeon awareness for altering surgical approach to minimize the risk of severe post-operative coronal imbalance. LEVEL OF EVIDENCE: Level III.